Merge pull request #910 from ericchiang/update-grpc

*: update grpc and correct protobuf generation

Makefile

@@ -16,10 +16,6 @@ user=$(shell id -u -n)
 group=$(shell id -g -n)
 
 export GOBIN=$(PWD)/bin
-# Prefer ./bin instead of system packages for things like protoc, where we want
-# to use the version dex uses, not whatever a developer has installed.
-export PATH=$(GOBIN):$(shell printenv PATH)
-export GO15VENDOREXPERIMENT=1
 
 LD_FLAGS="-w -X $(REPO_PATH)/version.Version=$(VERSION)"
 
@@ -74,10 +70,10 @@ docker-image: clean-release _output/bin/dex
 proto: api/api.pb.go server/internal/types.pb.go
 
 api/api.pb.go: api/api.proto bin/protoc bin/protoc-gen-go
-	@protoc --go_out=plugins=grpc:. api/*.proto
+	@./bin/protoc --go_out=plugins=grpc:. --plugin=protoc-gen-go=./bin/protoc-gen-go api/*.proto
 
 server/internal/types.pb.go: server/internal/types.proto bin/protoc bin/protoc-gen-go
-	@protoc --go_out=. server/internal/*.proto
+	@./bin/protoc --go_out=. --plugin=protoc-gen-go=./bin/protoc-gen-go server/internal/*.proto
 
 bin/protoc: scripts/get-protoc
 	@./scripts/get-protoc bin/protoc

api/api.pb.go

@@ -353,7 +353,7 @@ var _ grpc.ClientConn
 
 // This is a compile-time assertion to ensure that this generated file
 // is compatible with the grpc package it is being compiled against.
-const _ = grpc.SupportPackageIsVersion3
+const _ = grpc.SupportPackageIsVersion4
 
 // Client API for Dex service
 
@@ -702,14 +702,14 @@ var _Dex_serviceDesc = grpc.ServiceDesc{
 		},
 	},
 	Streams:  []grpc.StreamDesc{},
-	Metadata: fileDescriptor0,
+	Metadata: "api/api.proto",
 }
 
 func init() { proto.RegisterFile("api/api.proto", fileDescriptor0) }
 
 var fileDescriptor0 = []byte{
 	// 786 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x09, 0x6e, 0x88, 0x02, 0xff, 0x8c, 0x55, 0x6d, 0x4f, 0xdb, 0x48,
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x8c, 0x55, 0x6d, 0x4f, 0xdb, 0x48,
 	0x10, 0x4e, 0xe2, 0x90, 0x38, 0x93, 0xf7, 0x3d, 0x5e, 0x4c, 0xd0, 0x49, 0xb0, 0xe8, 0x24, 0xd0,
 	0x49, 0x70, 0x70, 0xd2, 0x9d, 0x74, 0xe8, 0xb8, 0x3b, 0xc1, 0xb5, 0x20, 0x55, 0x15, 0xb2, 0x9a,
 	0x7e, 0xac, 0x65, 0xe2, 0x01, 0x56, 0x18, 0xdb, 0xdd, 0xdd, 0x10, 0xda, 0x7f, 0x57, 0xf5, 0x8f,

glide.lock

@@ -1,5 +1,5 @@
-hash: ba77a77f03b1750479aa4a61de59d7a545dc8bd5c71be10e1c2e9afed37e1925
-updated: 2017-03-24T11:03:21.332291207-07:00
+hash: 94ea60e268ee0ed04e8affdee4db2884fd93ee68ed625d88ccc0e24565b98569
+updated: 2017-04-13T11:28:49.008994259-07:00
 imports:
 - name: github.com/beevik/etree
   version: 4cd0dd976db869f817248477718071a28e978df0
@@ -14,10 +14,12 @@ imports:
 - name: github.com/go-sql-driver/mysql
   version: 0b58b37b664c21f3010e836f1b931e1d0b0b0685
 - name: github.com/golang/protobuf
-  version: 874264fbbb43f4d91e999fecb4b40143ed611400
+  version: 2bba0603135d7d7f5cb73b2125beeda19c09f4ef
   subpackages:
   - proto
   - protoc-gen-go
+  - protoc-gen-go/grpc
+  - ptypes/any
 - name: github.com/gorilla/context
   version: aed02d124ae4a0e94fea4541c8effd05bf0c8296
 - name: github.com/gorilla/handlers
@@ -62,11 +64,12 @@ imports:
   - bcrypt
   - blowfish
 - name: golang.org/x/net
-  version: 6a513affb38dc9788b449d59ffed099b8de18fa0
+  version: 5602c733f70afc6dcec6766be0d5034d4c4f14de
   subpackages:
   - context
   - http2
   - http2/hpack
+  - idna
   - internal/timeseries
   - lex/httplex
   - trace
@@ -79,6 +82,13 @@ imports:
   version: 833a04a10549a95dc34458c195cbad61bbb6cb4d
   subpackages:
   - unix
+- name: golang.org/x/text
+  version: f4b4367115ec2de254587813edaa901bc1c723a8
+  subpackages:
+  - secure/bidirule
+  - transform
+  - unicode/bidi
+  - unicode/norm
 - name: google.golang.org/appengine
   version: 267c27e7492265b84fc6719503b14a1e17975d79
   subpackages:
@@ -89,16 +99,24 @@ imports:
   - internal/remote_api
   - internal/urlfetch
   - urlfetch
+- name: google.golang.org/genproto
+  version: 411e09b969b1170a9f0c467558eb4c4c110d9c77
+  subpackages:
+  - googleapis/rpc/status
 - name: google.golang.org/grpc
-  version: b1a2821ca5a4fd6b6e48ddfbb7d6d7584d839d21
+  version: 0e8b58d22f34640cb17dbbed1c8aef3b8dcc0e97
   subpackages:
   - codes
   - credentials
   - grpclog
   - internal
+  - keepalive
   - metadata
   - naming
   - peer
+  - stats
+  - status
+  - tap
   - transport
 - name: gopkg.in/asn1-ber.v1
   version: 4e86f4367175e39f69d9358a5f17b4dda270378d

glide.yaml

@@ -32,7 +32,7 @@ import:
 
 # Imported directly and by several third party packages.
 - package: golang.org/x/net
-  version: 6a513affb38dc9788b449d59ffed099b8de18fa0
+  version: 5602c733f70afc6dcec6766be0d5034d4c4f14de
   subpackages:
   - context
   - http2
@@ -40,6 +40,8 @@ import:
   - internal/timeseries
   - lex/httplex
   - trace
+- package: golang.org/x/text
+  version: f4b4367115ec2de254587813edaa901bc1c723a8
 
 # Used for parsing configs.
 - package: github.com/ghodss/yaml
@@ -109,7 +111,7 @@ import:
 
 # gRPC and protobuf are use for the API. Also import x/net/http2 stack.
 - package: google.golang.org/grpc
-  version: b1a2821ca5a4fd6b6e48ddfbb7d6d7584d839d21
+  version: 0e8b58d22f34640cb17dbbed1c8aef3b8dcc0e97
   subpackages:
   - codes
   - credentials
@@ -120,10 +122,13 @@ import:
   - peer
   - transport
 - package: github.com/golang/protobuf
-  version: 874264fbbb43f4d91e999fecb4b40143ed611400
+  version: 2bba0603135d7d7f5cb73b2125beeda19c09f4ef
   subpackages:
   - proto
   - protoc-gen-go
+  - protoc-gen-go/grpc
+- package: google.golang.org/genproto
+  version: 411e09b969b1170a9f0c467558eb4c4c110d9c77
 
 # Structured logging
 - package: github.com/Sirupsen/logrus

server/internal/types.pb.go

@@ -63,7 +63,7 @@ func init() { proto.RegisterFile("server/internal/types.proto", fileDescriptor0)
 
 var fileDescriptor0 = []byte{
 	// 157 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x09, 0x6e, 0x88, 0x02, 0xff, 0xe2, 0x92, 0x2e, 0x4e, 0x2d, 0x2a,
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0x92, 0x2e, 0x4e, 0x2d, 0x2a,
 	0x4b, 0x2d, 0xd2, 0xcf, 0xcc, 0x2b, 0x49, 0x2d, 0xca, 0x4b, 0xcc, 0xd1, 0x2f, 0xa9, 0x2c, 0x48,
 	0x2d, 0xd6, 0x2b, 0x28, 0xca, 0x2f, 0xc9, 0x17, 0xe2, 0x80, 0x89, 0x2a, 0x39, 0x73, 0xf1, 0x04,
 	0xa5, 0xa6, 0x15, 0xa5, 0x16, 0x67, 0x84, 0xe4, 0x67, 0xa7, 0xe6, 0x09, 0xc9, 0x72, 0x71, 0x15,

vendor/github.com/golang/protobuf/proto/decode.go

@@ -61,7 +61,6 @@ var ErrInternalBadWireType = errors.New("proto: internal error: bad wiretype for
 // int32, int64, uint32, uint64, bool, and enum
 // protocol buffer types.
 func DecodeVarint(buf []byte) (x uint64, n int) {
-	// x, n already 0
 	for shift := uint(0); shift < 64; shift += 7 {
 		if n >= len(buf) {
 			return 0, 0
@@ -78,13 +77,7 @@ func DecodeVarint(buf []byte) (x uint64, n int) {
 	return 0, 0
 }
 
-// DecodeVarint reads a varint-encoded integer from the Buffer.
-// This is the format for the
-// int32, int64, uint32, uint64, bool, and enum
-// protocol buffer types.
-func (p *Buffer) DecodeVarint() (x uint64, err error) {
-	// x, err already 0
-
+func (p *Buffer) decodeVarintSlow() (x uint64, err error) {
 	i := p.index
 	l := len(p.buf)
 
@@ -107,6 +100,107 @@ func (p *Buffer) DecodeVarint() (x uint64, err error) {
 	return
 }
 
+// DecodeVarint reads a varint-encoded integer from the Buffer.
+// This is the format for the
+// int32, int64, uint32, uint64, bool, and enum
+// protocol buffer types.
+func (p *Buffer) DecodeVarint() (x uint64, err error) {
+	i := p.index
+	buf := p.buf
+
+	if i >= len(buf) {
+		return 0, io.ErrUnexpectedEOF
+	} else if buf[i] < 0x80 {
+		p.index++
+		return uint64(buf[i]), nil
+	} else if len(buf)-i < 10 {
+		return p.decodeVarintSlow()
+	}
+
+	var b uint64
+	// we already checked the first byte
+	x = uint64(buf[i]) - 0x80
+	i++
+
+	b = uint64(buf[i])
+	i++
+	x += b << 7
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 7
+
+	b = uint64(buf[i])
+	i++
+	x += b << 14
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 14
+
+	b = uint64(buf[i])
+	i++
+	x += b << 21
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 21
+
+	b = uint64(buf[i])
+	i++
+	x += b << 28
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 28
+
+	b = uint64(buf[i])
+	i++
+	x += b << 35
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 35
+
+	b = uint64(buf[i])
+	i++
+	x += b << 42
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 42
+
+	b = uint64(buf[i])
+	i++
+	x += b << 49
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 49
+
+	b = uint64(buf[i])
+	i++
+	x += b << 56
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 56
+
+	b = uint64(buf[i])
+	i++
+	x += b << 63
+	if b&0x80 == 0 {
+		goto done
+	}
+	// x -= 0x80 << 63 // Always zero.
+
+	return 0, errOverflow
+
+done:
+	p.index = i
+	return x, nil
+}
+
 // DecodeFixed64 reads a 64-bit integer from the Buffer.
 // This is the format for the
 // fixed64, sfixed64, and double protocol buffer types.
@@ -340,6 +434,8 @@ func (p *Buffer) DecodeGroup(pb Message) error {
 // Buffer and places the decoded result in pb.  If the struct
 // underlying pb does not match the data in the buffer, the results can be
 // unpredictable.
+//
+// Unlike proto.Unmarshal, this does not reset pb before starting to unmarshal.
 func (p *Buffer) Unmarshal(pb Message) error {
 	// If the object can unmarshal itself, let it.
 	if u, ok := pb.(Unmarshaler); ok {

vendor/github.com/golang/protobuf/proto/encode.go

@@ -234,10 +234,6 @@ func Marshal(pb Message) ([]byte, error) {
 	}
 	p := NewBuffer(nil)
 	err := p.Marshal(pb)
-	var state errorState
-	if err != nil && !state.shouldContinue(err, nil) {
-		return nil, err
-	}
 	if p.buf == nil && err == nil {
 		// Return a non-nil slice on success.
 		return []byte{}, nil
@@ -266,11 +262,8 @@ func (p *Buffer) Marshal(pb Message) error {
 	// Can the object marshal itself?
 	if m, ok := pb.(Marshaler); ok {
 		data, err := m.Marshal()
-		if err != nil {
-			return err
-		}
 		p.buf = append(p.buf, data...)
-		return nil
+		return err
 	}
 
 	t, base, err := getbase(pb)
@@ -282,7 +275,7 @@ func (p *Buffer) Marshal(pb Message) error {
 	}
 
 	if collectStats {
-		stats.Encode++
+		(stats).Encode++ // Parens are to work around a goimports bug.
 	}
 
 	if len(p.buf) > maxMarshalSize {
@@ -309,7 +302,7 @@ func Size(pb Message) (n int) {
 	}
 
 	if collectStats {
-		stats.Size++
+		(stats).Size++ // Parens are to work around a goimports bug.
 	}
 
 	return
@@ -1014,7 +1007,6 @@ func size_slice_struct_message(p *Properties, base structPointer) (n int) {
 		if p.isMarshaler {
 			m := structPointer_Interface(structp, p.stype).(Marshaler)
 			data, _ := m.Marshal()
-			n += len(p.tagcode)
 			n += sizeRawBytes(data)
 			continue
 		}
@@ -1083,10 +1075,17 @@ func (o *Buffer) enc_map(p *Properties, base structPointer) error {
 
 func (o *Buffer) enc_exts(p *Properties, base structPointer) error {
 	exts := structPointer_Extensions(base, p.field)
-	if err := encodeExtensions(exts); err != nil {
+
+	v, mu := exts.extensionsRead()
+	if v == nil {
+		return nil
+	}
+
+	mu.Lock()
+	defer mu.Unlock()
+	if err := encodeExtensionsMap(v); err != nil {
 		return err
 	}
-	v, _ := exts.extensionsRead()
 
 	return o.enc_map_body(v)
 }

vendor/github.com/golang/protobuf/proto/equal.go

@@ -54,13 +54,17 @@ Equality is defined in this way:
     in a proto3 .proto file, fields are not "set"; specifically,
     zero length proto3 "bytes" fields are equal (nil == {}).
   - Two repeated fields are equal iff their lengths are the same,
-    and their corresponding elements are equal (a "bytes" field,
-    although represented by []byte, is not a repeated field)
+    and their corresponding elements are equal. Note a "bytes" field,
+    although represented by []byte, is not a repeated field and the
+    rule for the scalar fields described above applies.
   - Two unset fields are equal.
   - Two unknown field sets are equal if their current
     encoded state is equal.
   - Two extension sets are equal iff they have corresponding
     elements that are pairwise equal.
+  - Two map fields are equal iff their lengths are the same,
+    and they contain the same set of elements. Zero-length map
+    fields are equal.
   - Every other combination of things are not equal.
 
 The return value is undefined if a and b are not protocol buffers.

vendor/github.com/golang/protobuf/proto/extensions.go

@@ -154,6 +154,7 @@ type ExtensionDesc struct {
 	Field         int32       // field number
 	Name          string      // fully-qualified name of extension, for text formatting
 	Tag           string      // protobuf tag style
+	Filename      string      // name of the file in which the extension is defined
 }
 
 func (ed *ExtensionDesc) repeated() bool {
@@ -500,6 +501,9 @@ func ExtensionDescs(pb Message) ([]*ExtensionDesc, error) {
 	registeredExtensions := RegisteredExtensions(pb)
 
 	emap, mu := epb.extensionsRead()
+	if emap == nil {
+		return nil, nil
+	}
 	mu.Lock()
 	defer mu.Unlock()
 	extensions := make([]*ExtensionDesc, 0, len(emap))

vendor/github.com/golang/protobuf/proto/lib.go

@@ -308,7 +308,7 @@ func GetStats() Stats { return stats }
 // temporary Buffer and are fine for most applications.
 type Buffer struct {
 	buf   []byte // encode/decode byte stream
-	index int    // write point
+	index int    // read point
 
 	// pools of basic types to amortize allocation.
 	bools   []bool

vendor/github.com/golang/protobuf/proto/properties.go

@@ -844,7 +844,15 @@ func RegisterType(x Message, name string) {
 }
 
 // MessageName returns the fully-qualified proto name for the given message type.
-func MessageName(x Message) string { return revProtoTypes[reflect.TypeOf(x)] }
+func MessageName(x Message) string {
+	type xname interface {
+		XXX_MessageName() string
+	}
+	if m, ok := x.(xname); ok {
+		return m.XXX_MessageName()
+	}
+	return revProtoTypes[reflect.TypeOf(x)]
+}
 
 // MessageType returns the message type (pointer to struct) for a named message.
 func MessageType(name string) reflect.Type { return protoTypes[name] }

vendor/github.com/golang/protobuf/proto/text_parser.go

@@ -44,6 +44,9 @@ import (
 	"unicode/utf8"
 )
 
+// Error string emitted when deserializing Any and fields are already set
+const anyRepeatedlyUnpacked = "Any message unpacked multiple times, or %q already set"
+
 type ParseError struct {
 	Message string
 	Line    int // 1-based line number
@@ -508,8 +511,16 @@ func (p *textParser) readStruct(sv reflect.Value, terminator string) error {
 				if err != nil {
 					return p.errorf("failed to marshal message of type %q: %v", messageName, err)
 				}
+				if fieldSet["type_url"] {
+					return p.errorf(anyRepeatedlyUnpacked, "type_url")
+				}
+				if fieldSet["value"] {
+					return p.errorf(anyRepeatedlyUnpacked, "value")
+				}
 				sv.FieldByName("TypeUrl").SetString(extName)
 				sv.FieldByName("Value").SetBytes(b)
+				fieldSet["type_url"] = true
+				fieldSet["value"] = true
 				continue
 			}
 
@@ -581,7 +592,11 @@ func (p *textParser) readStruct(sv reflect.Value, terminator string) error {
 			props = oop.Prop
 			nv := reflect.New(oop.Type.Elem())
 			dst = nv.Elem().Field(0)
-			sv.Field(oop.Field).Set(nv)
+			field := sv.Field(oop.Field)
+			if !field.IsNil() {
+				return p.errorf("field '%s' would overwrite already parsed oneof '%s'", name, sv.Type().Field(oop.Field).Name)
+			}
+			field.Set(nv)
 		}
 		if !dst.IsValid() {
 			return p.errorf("unknown field name %q in %v", name, st)
@@ -781,12 +796,12 @@ func (p *textParser) readAny(v reflect.Value, props *Properties) error {
 		fv.Set(reflect.Append(fv, reflect.New(at.Elem()).Elem()))
 		return p.readAny(fv.Index(fv.Len()-1), props)
 	case reflect.Bool:
-		// Either "true", "false", 1 or 0.
+		// true/1/t/True or false/f/0/False.
 		switch tok.value {
-		case "true", "1":
+		case "true", "1", "t", "True":
 			fv.SetBool(true)
 			return nil
-		case "false", "0":
+		case "false", "0", "f", "False":
 			fv.SetBool(false)
 			return nil
 		}

vendor/github.com/golang/protobuf/protoc-gen-go/grpc/grpc.go

@@ -0,0 +1,463 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2015 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Package grpc outputs gRPC service descriptions in Go code.
+// It runs as a plugin for the Go protocol buffer compiler plugin.
+// It is linked in to protoc-gen-go.
+package grpc
+
+import (
+	"fmt"
+	"path"
+	"strconv"
+	"strings"
+
+	pb "github.com/golang/protobuf/protoc-gen-go/descriptor"
+	"github.com/golang/protobuf/protoc-gen-go/generator"
+)
+
+// generatedCodeVersion indicates a version of the generated code.
+// It is incremented whenever an incompatibility between the generated code and
+// the grpc package is introduced; the generated code references
+// a constant, grpc.SupportPackageIsVersionN (where N is generatedCodeVersion).
+const generatedCodeVersion = 4
+
+// Paths for packages used by code generated in this file,
+// relative to the import_prefix of the generator.Generator.
+const (
+	contextPkgPath = "golang.org/x/net/context"
+	grpcPkgPath    = "google.golang.org/grpc"
+)
+
+func init() {
+	generator.RegisterPlugin(new(grpc))
+}
+
+// grpc is an implementation of the Go protocol buffer compiler's
+// plugin architecture.  It generates bindings for gRPC support.
+type grpc struct {
+	gen *generator.Generator
+}
+
+// Name returns the name of this plugin, "grpc".
+func (g *grpc) Name() string {
+	return "grpc"
+}
+
+// The names for packages imported in the generated code.
+// They may vary from the final path component of the import path
+// if the name is used by other packages.
+var (
+	contextPkg string
+	grpcPkg    string
+)
+
+// Init initializes the plugin.
+func (g *grpc) Init(gen *generator.Generator) {
+	g.gen = gen
+	contextPkg = generator.RegisterUniquePackageName("context", nil)
+	grpcPkg = generator.RegisterUniquePackageName("grpc", nil)
+}
+
+// Given a type name defined in a .proto, return its object.
+// Also record that we're using it, to guarantee the associated import.
+func (g *grpc) objectNamed(name string) generator.Object {
+	g.gen.RecordTypeUse(name)
+	return g.gen.ObjectNamed(name)
+}
+
+// Given a type name defined in a .proto, return its name as we will print it.
+func (g *grpc) typeName(str string) string {
+	return g.gen.TypeName(g.objectNamed(str))
+}
+
+// P forwards to g.gen.P.
+func (g *grpc) P(args ...interface{}) { g.gen.P(args...) }
+
+// Generate generates code for the services in the given file.
+func (g *grpc) Generate(file *generator.FileDescriptor) {
+	if len(file.FileDescriptorProto.Service) == 0 {
+		return
+	}
+
+	g.P("// Reference imports to suppress errors if they are not otherwise used.")
+	g.P("var _ ", contextPkg, ".Context")
+	g.P("var _ ", grpcPkg, ".ClientConn")
+	g.P()
+
+	// Assert version compatibility.
+	g.P("// This is a compile-time assertion to ensure that this generated file")
+	g.P("// is compatible with the grpc package it is being compiled against.")
+	g.P("const _ = ", grpcPkg, ".SupportPackageIsVersion", generatedCodeVersion)
+	g.P()
+
+	for i, service := range file.FileDescriptorProto.Service {
+		g.generateService(file, service, i)
+	}
+}
+
+// GenerateImports generates the import declaration for this file.
+func (g *grpc) GenerateImports(file *generator.FileDescriptor) {
+	if len(file.FileDescriptorProto.Service) == 0 {
+		return
+	}
+	g.P("import (")
+	g.P(contextPkg, " ", strconv.Quote(path.Join(g.gen.ImportPrefix, contextPkgPath)))
+	g.P(grpcPkg, " ", strconv.Quote(path.Join(g.gen.ImportPrefix, grpcPkgPath)))
+	g.P(")")
+	g.P()
+}
+
+// reservedClientName records whether a client name is reserved on the client side.
+var reservedClientName = map[string]bool{
+// TODO: do we need any in gRPC?
+}
+
+func unexport(s string) string { return strings.ToLower(s[:1]) + s[1:] }
+
+// generateService generates all the code for the named service.
+func (g *grpc) generateService(file *generator.FileDescriptor, service *pb.ServiceDescriptorProto, index int) {
+	path := fmt.Sprintf("6,%d", index) // 6 means service.
+
+	origServName := service.GetName()
+	fullServName := origServName
+	if pkg := file.GetPackage(); pkg != "" {
+		fullServName = pkg + "." + fullServName
+	}
+	servName := generator.CamelCase(origServName)
+
+	g.P()
+	g.P("// Client API for ", servName, " service")
+	g.P()
+
+	// Client interface.
+	g.P("type ", servName, "Client interface {")
+	for i, method := range service.Method {
+		g.gen.PrintComments(fmt.Sprintf("%s,2,%d", path, i)) // 2 means method in a service.
+		g.P(g.generateClientSignature(servName, method))
+	}
+	g.P("}")
+	g.P()
+
+	// Client structure.
+	g.P("type ", unexport(servName), "Client struct {")
+	g.P("cc *", grpcPkg, ".ClientConn")
+	g.P("}")
+	g.P()
+
+	// NewClient factory.
+	g.P("func New", servName, "Client (cc *", grpcPkg, ".ClientConn) ", servName, "Client {")
+	g.P("return &", unexport(servName), "Client{cc}")
+	g.P("}")
+	g.P()
+
+	var methodIndex, streamIndex int
+	serviceDescVar := "_" + servName + "_serviceDesc"
+	// Client method implementations.
+	for _, method := range service.Method {
+		var descExpr string
+		if !method.GetServerStreaming() && !method.GetClientStreaming() {
+			// Unary RPC method
+			descExpr = fmt.Sprintf("&%s.Methods[%d]", serviceDescVar, methodIndex)
+			methodIndex++
+		} else {
+			// Streaming RPC method
+			descExpr = fmt.Sprintf("&%s.Streams[%d]", serviceDescVar, streamIndex)
+			streamIndex++
+		}
+		g.generateClientMethod(servName, fullServName, serviceDescVar, method, descExpr)
+	}
+
+	g.P("// Server API for ", servName, " service")
+	g.P()
+
+	// Server interface.
+	serverType := servName + "Server"
+	g.P("type ", serverType, " interface {")
+	for i, method := range service.Method {
+		g.gen.PrintComments(fmt.Sprintf("%s,2,%d", path, i)) // 2 means method in a service.
+		g.P(g.generateServerSignature(servName, method))
+	}
+	g.P("}")
+	g.P()
+
+	// Server registration.
+	g.P("func Register", servName, "Server(s *", grpcPkg, ".Server, srv ", serverType, ") {")
+	g.P("s.RegisterService(&", serviceDescVar, `, srv)`)
+	g.P("}")
+	g.P()
+
+	// Server handler implementations.
+	var handlerNames []string
+	for _, method := range service.Method {
+		hname := g.generateServerMethod(servName, fullServName, method)
+		handlerNames = append(handlerNames, hname)
+	}
+
+	// Service descriptor.
+	g.P("var ", serviceDescVar, " = ", grpcPkg, ".ServiceDesc {")
+	g.P("ServiceName: ", strconv.Quote(fullServName), ",")
+	g.P("HandlerType: (*", serverType, ")(nil),")
+	g.P("Methods: []", grpcPkg, ".MethodDesc{")
+	for i, method := range service.Method {
+		if method.GetServerStreaming() || method.GetClientStreaming() {
+			continue
+		}
+		g.P("{")
+		g.P("MethodName: ", strconv.Quote(method.GetName()), ",")
+		g.P("Handler: ", handlerNames[i], ",")
+		g.P("},")
+	}
+	g.P("},")
+	g.P("Streams: []", grpcPkg, ".StreamDesc{")
+	for i, method := range service.Method {
+		if !method.GetServerStreaming() && !method.GetClientStreaming() {
+			continue
+		}
+		g.P("{")
+		g.P("StreamName: ", strconv.Quote(method.GetName()), ",")
+		g.P("Handler: ", handlerNames[i], ",")
+		if method.GetServerStreaming() {
+			g.P("ServerStreams: true,")
+		}
+		if method.GetClientStreaming() {
+			g.P("ClientStreams: true,")
+		}
+		g.P("},")
+	}
+	g.P("},")
+	g.P("Metadata: \"", file.GetName(), "\",")
+	g.P("}")
+	g.P()
+}
+
+// generateClientSignature returns the client-side signature for a method.
+func (g *grpc) generateClientSignature(servName string, method *pb.MethodDescriptorProto) string {
+	origMethName := method.GetName()
+	methName := generator.CamelCase(origMethName)
+	if reservedClientName[methName] {
+		methName += "_"
+	}
+	reqArg := ", in *" + g.typeName(method.GetInputType())
+	if method.GetClientStreaming() {
+		reqArg = ""
+	}
+	respName := "*" + g.typeName(method.GetOutputType())
+	if method.GetServerStreaming() || method.GetClientStreaming() {
+		respName = servName + "_" + generator.CamelCase(origMethName) + "Client"
+	}
+	return fmt.Sprintf("%s(ctx %s.Context%s, opts ...%s.CallOption) (%s, error)", methName, contextPkg, reqArg, grpcPkg, respName)
+}
+
+func (g *grpc) generateClientMethod(servName, fullServName, serviceDescVar string, method *pb.MethodDescriptorProto, descExpr string) {
+	sname := fmt.Sprintf("/%s/%s", fullServName, method.GetName())
+	methName := generator.CamelCase(method.GetName())
+	inType := g.typeName(method.GetInputType())
+	outType := g.typeName(method.GetOutputType())
+
+	g.P("func (c *", unexport(servName), "Client) ", g.generateClientSignature(servName, method), "{")
+	if !method.GetServerStreaming() && !method.GetClientStreaming() {
+		g.P("out := new(", outType, ")")
+		// TODO: Pass descExpr to Invoke.
+		g.P("err := ", grpcPkg, `.Invoke(ctx, "`, sname, `", in, out, c.cc, opts...)`)
+		g.P("if err != nil { return nil, err }")
+		g.P("return out, nil")
+		g.P("}")
+		g.P()
+		return
+	}
+	streamType := unexport(servName) + methName + "Client"
+	g.P("stream, err := ", grpcPkg, ".NewClientStream(ctx, ", descExpr, `, c.cc, "`, sname, `", opts...)`)
+	g.P("if err != nil { return nil, err }")
+	g.P("x := &", streamType, "{stream}")
+	if !method.GetClientStreaming() {
+		g.P("if err := x.ClientStream.SendMsg(in); err != nil { return nil, err }")
+		g.P("if err := x.ClientStream.CloseSend(); err != nil { return nil, err }")
+	}
+	g.P("return x, nil")
+	g.P("}")
+	g.P()
+
+	genSend := method.GetClientStreaming()
+	genRecv := method.GetServerStreaming()
+	genCloseAndRecv := !method.GetServerStreaming()
+
+	// Stream auxiliary types and methods.
+	g.P("type ", servName, "_", methName, "Client interface {")
+	if genSend {
+		g.P("Send(*", inType, ") error")
+	}
+	if genRecv {
+		g.P("Recv() (*", outType, ", error)")
+	}
+	if genCloseAndRecv {
+		g.P("CloseAndRecv() (*", outType, ", error)")
+	}
+	g.P(grpcPkg, ".ClientStream")
+	g.P("}")
+	g.P()
+
+	g.P("type ", streamType, " struct {")
+	g.P(grpcPkg, ".ClientStream")
+	g.P("}")
+	g.P()
+
+	if genSend {
+		g.P("func (x *", streamType, ") Send(m *", inType, ") error {")
+		g.P("return x.ClientStream.SendMsg(m)")
+		g.P("}")
+		g.P()
+	}
+	if genRecv {
+		g.P("func (x *", streamType, ") Recv() (*", outType, ", error) {")
+		g.P("m := new(", outType, ")")
+		g.P("if err := x.ClientStream.RecvMsg(m); err != nil { return nil, err }")
+		g.P("return m, nil")
+		g.P("}")
+		g.P()
+	}
+	if genCloseAndRecv {
+		g.P("func (x *", streamType, ") CloseAndRecv() (*", outType, ", error) {")
+		g.P("if err := x.ClientStream.CloseSend(); err != nil { return nil, err }")
+		g.P("m := new(", outType, ")")
+		g.P("if err := x.ClientStream.RecvMsg(m); err != nil { return nil, err }")
+		g.P("return m, nil")
+		g.P("}")
+		g.P()
+	}
+}
+
+// generateServerSignature returns the server-side signature for a method.
+func (g *grpc) generateServerSignature(servName string, method *pb.MethodDescriptorProto) string {
+	origMethName := method.GetName()
+	methName := generator.CamelCase(origMethName)
+	if reservedClientName[methName] {
+		methName += "_"
+	}
+
+	var reqArgs []string
+	ret := "error"
+	if !method.GetServerStreaming() && !method.GetClientStreaming() {
+		reqArgs = append(reqArgs, contextPkg+".Context")
+		ret = "(*" + g.typeName(method.GetOutputType()) + ", error)"
+	}
+	if !method.GetClientStreaming() {
+		reqArgs = append(reqArgs, "*"+g.typeName(method.GetInputType()))
+	}
+	if method.GetServerStreaming() || method.GetClientStreaming() {
+		reqArgs = append(reqArgs, servName+"_"+generator.CamelCase(origMethName)+"Server")
+	}
+
+	return methName + "(" + strings.Join(reqArgs, ", ") + ") " + ret
+}
+
+func (g *grpc) generateServerMethod(servName, fullServName string, method *pb.MethodDescriptorProto) string {
+	methName := generator.CamelCase(method.GetName())
+	hname := fmt.Sprintf("_%s_%s_Handler", servName, methName)
+	inType := g.typeName(method.GetInputType())
+	outType := g.typeName(method.GetOutputType())
+
+	if !method.GetServerStreaming() && !method.GetClientStreaming() {
+		g.P("func ", hname, "(srv interface{}, ctx ", contextPkg, ".Context, dec func(interface{}) error, interceptor ", grpcPkg, ".UnaryServerInterceptor) (interface{}, error) {")
+		g.P("in := new(", inType, ")")
+		g.P("if err := dec(in); err != nil { return nil, err }")
+		g.P("if interceptor == nil { return srv.(", servName, "Server).", methName, "(ctx, in) }")
+		g.P("info := &", grpcPkg, ".UnaryServerInfo{")
+		g.P("Server: srv,")
+		g.P("FullMethod: ", strconv.Quote(fmt.Sprintf("/%s/%s", fullServName, methName)), ",")
+		g.P("}")
+		g.P("handler := func(ctx ", contextPkg, ".Context, req interface{}) (interface{}, error) {")
+		g.P("return srv.(", servName, "Server).", methName, "(ctx, req.(*", inType, "))")
+		g.P("}")
+		g.P("return interceptor(ctx, in, info, handler)")
+		g.P("}")
+		g.P()
+		return hname
+	}
+	streamType := unexport(servName) + methName + "Server"
+	g.P("func ", hname, "(srv interface{}, stream ", grpcPkg, ".ServerStream) error {")
+	if !method.GetClientStreaming() {
+		g.P("m := new(", inType, ")")
+		g.P("if err := stream.RecvMsg(m); err != nil { return err }")
+		g.P("return srv.(", servName, "Server).", methName, "(m, &", streamType, "{stream})")
+	} else {
+		g.P("return srv.(", servName, "Server).", methName, "(&", streamType, "{stream})")
+	}
+	g.P("}")
+	g.P()
+
+	genSend := method.GetServerStreaming()
+	genSendAndClose := !method.GetServerStreaming()
+	genRecv := method.GetClientStreaming()
+
+	// Stream auxiliary types and methods.
+	g.P("type ", servName, "_", methName, "Server interface {")
+	if genSend {
+		g.P("Send(*", outType, ") error")
+	}
+	if genSendAndClose {
+		g.P("SendAndClose(*", outType, ") error")
+	}
+	if genRecv {
+		g.P("Recv() (*", inType, ", error)")
+	}
+	g.P(grpcPkg, ".ServerStream")
+	g.P("}")
+	g.P()
+
+	g.P("type ", streamType, " struct {")
+	g.P(grpcPkg, ".ServerStream")
+	g.P("}")
+	g.P()
+
+	if genSend {
+		g.P("func (x *", streamType, ") Send(m *", outType, ") error {")
+		g.P("return x.ServerStream.SendMsg(m)")
+		g.P("}")
+		g.P()
+	}
+	if genSendAndClose {
+		g.P("func (x *", streamType, ") SendAndClose(m *", outType, ") error {")
+		g.P("return x.ServerStream.SendMsg(m)")
+		g.P("}")
+		g.P()
+	}
+	if genRecv {
+		g.P("func (x *", streamType, ") Recv() (*", inType, ", error) {")
+		g.P("m := new(", inType, ")")
+		g.P("if err := x.ServerStream.RecvMsg(m); err != nil { return nil, err }")
+		g.P("return m, nil")
+		g.P("}")
+		g.P()
+	}
+
+	return hname
+}

vendor/github.com/golang/protobuf/ptypes/any/any.pb.go

@@ -0,0 +1,155 @@
+// Code generated by protoc-gen-go.
+// source: github.com/golang/protobuf/ptypes/any/any.proto
+// DO NOT EDIT!
+
+/*
+Package any is a generated protocol buffer package.
+
+It is generated from these files:
+	github.com/golang/protobuf/ptypes/any/any.proto
+
+It has these top-level messages:
+	Any
+*/
+package any
+
+import proto "github.com/golang/protobuf/proto"
+import fmt "fmt"
+import math "math"
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
+
+// `Any` contains an arbitrary serialized protocol buffer message along with a
+// URL that describes the type of the serialized message.
+//
+// Protobuf library provides support to pack/unpack Any values in the form
+// of utility functions or additional generated methods of the Any type.
+//
+// Example 1: Pack and unpack a message in C++.
+//
+//     Foo foo = ...;
+//     Any any;
+//     any.PackFrom(foo);
+//     ...
+//     if (any.UnpackTo(&foo)) {
+//       ...
+//     }
+//
+// Example 2: Pack and unpack a message in Java.
+//
+//     Foo foo = ...;
+//     Any any = Any.pack(foo);
+//     ...
+//     if (any.is(Foo.class)) {
+//       foo = any.unpack(Foo.class);
+//     }
+//
+//  Example 3: Pack and unpack a message in Python.
+//
+//     foo = Foo(...)
+//     any = Any()
+//     any.Pack(foo)
+//     ...
+//     if any.Is(Foo.DESCRIPTOR):
+//       any.Unpack(foo)
+//       ...
+//
+// The pack methods provided by protobuf library will by default use
+// 'type.googleapis.com/full.type.name' as the type URL and the unpack
+// methods only use the fully qualified type name after the last '/'
+// in the type URL, for example "foo.bar.com/x/y.z" will yield type
+// name "y.z".
+//
+//
+// JSON
+// ====
+// The JSON representation of an `Any` value uses the regular
+// representation of the deserialized, embedded message, with an
+// additional field `@type` which contains the type URL. Example:
+//
+//     package google.profile;
+//     message Person {
+//       string first_name = 1;
+//       string last_name = 2;
+//     }
+//
+//     {
+//       "@type": "type.googleapis.com/google.profile.Person",
+//       "firstName": <string>,
+//       "lastName": <string>
+//     }
+//
+// If the embedded message type is well-known and has a custom JSON
+// representation, that representation will be embedded adding a field
+// `value` which holds the custom JSON in addition to the `@type`
+// field. Example (for message [google.protobuf.Duration][]):
+//
+//     {
+//       "@type": "type.googleapis.com/google.protobuf.Duration",
+//       "value": "1.212s"
+//     }
+//
+type Any struct {
+	// A URL/resource name whose content describes the type of the
+	// serialized protocol buffer message.
+	//
+	// For URLs which use the scheme `http`, `https`, or no scheme, the
+	// following restrictions and interpretations apply:
+	//
+	// * If no scheme is provided, `https` is assumed.
+	// * The last segment of the URL's path must represent the fully
+	//   qualified name of the type (as in `path/google.protobuf.Duration`).
+	//   The name should be in a canonical form (e.g., leading "." is
+	//   not accepted).
+	// * An HTTP GET on the URL must yield a [google.protobuf.Type][]
+	//   value in binary format, or produce an error.
+	// * Applications are allowed to cache lookup results based on the
+	//   URL, or have them precompiled into a binary to avoid any
+	//   lookup. Therefore, binary compatibility needs to be preserved
+	//   on changes to types. (Use versioned type names to manage
+	//   breaking changes.)
+	//
+	// Schemes other than `http`, `https` (or the empty scheme) might be
+	// used with implementation specific semantics.
+	//
+	TypeUrl string `protobuf:"bytes,1,opt,name=type_url,json=typeUrl" json:"type_url,omitempty"`
+	// Must be a valid serialized protocol buffer of the above specified type.
+	Value []byte `protobuf:"bytes,2,opt,name=value,proto3" json:"value,omitempty"`
+}
+
+func (m *Any) Reset()                    { *m = Any{} }
+func (m *Any) String() string            { return proto.CompactTextString(m) }
+func (*Any) ProtoMessage()               {}
+func (*Any) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{0} }
+func (*Any) XXX_WellKnownType() string   { return "Any" }
+
+func init() {
+	proto.RegisterType((*Any)(nil), "google.protobuf.Any")
+}
+
+func init() { proto.RegisterFile("github.com/golang/protobuf/ptypes/any/any.proto", fileDescriptor0) }
+
+var fileDescriptor0 = []byte{
+	// 187 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x09, 0x6e, 0x88, 0x02, 0xff, 0xe2, 0xd2, 0x4f, 0xcf, 0x2c, 0xc9,
+	0x28, 0x4d, 0xd2, 0x4b, 0xce, 0xcf, 0xd5, 0x4f, 0xcf, 0xcf, 0x49, 0xcc, 0x4b, 0xd7, 0x2f, 0x28,
+	0xca, 0x2f, 0xc9, 0x4f, 0x2a, 0x4d, 0xd3, 0x2f, 0x28, 0xa9, 0x2c, 0x48, 0x2d, 0xd6, 0x4f, 0xcc,
+	0xab, 0x04, 0x61, 0x3d, 0xb0, 0xb8, 0x10, 0x7f, 0x7a, 0x7e, 0x7e, 0x7a, 0x4e, 0xaa, 0x1e, 0x4c,
+	0x95, 0x92, 0x19, 0x17, 0xb3, 0x63, 0x5e, 0xa5, 0x90, 0x24, 0x17, 0x07, 0x48, 0x79, 0x7c, 0x69,
+	0x51, 0x8e, 0x04, 0xa3, 0x02, 0xa3, 0x06, 0x67, 0x10, 0x3b, 0x88, 0x1f, 0x5a, 0x94, 0x23, 0x24,
+	0xc2, 0xc5, 0x5a, 0x96, 0x98, 0x53, 0x9a, 0x2a, 0xc1, 0xa4, 0xc0, 0xa8, 0xc1, 0x13, 0x04, 0xe1,
+	0x38, 0x15, 0x71, 0x09, 0x27, 0xe7, 0xe7, 0xea, 0xa1, 0x19, 0xe7, 0xc4, 0xe1, 0x98, 0x57, 0x19,
+	0x00, 0xe2, 0x04, 0x30, 0x46, 0xa9, 0x12, 0xe5, 0xb8, 0x05, 0x8c, 0x8c, 0x8b, 0x98, 0x98, 0xdd,
+	0x03, 0x9c, 0x56, 0x31, 0xc9, 0xb9, 0x43, 0x4c, 0x0b, 0x80, 0xaa, 0xd2, 0x0b, 0x4f, 0xcd, 0xc9,
+	0xf1, 0xce, 0xcb, 0x2f, 0xcf, 0x0b, 0x01, 0xa9, 0x4e, 0x62, 0x03, 0x6b, 0x37, 0x06, 0x04, 0x00,
+	0x00, 0xff, 0xff, 0xc6, 0x4d, 0x03, 0x23, 0xf6, 0x00, 0x00, 0x00,
+}

vendor/golang.org/x/net/context/context.go

@@ -7,7 +7,7 @@
 // and between processes.
 //
 // Incoming requests to a server should create a Context, and outgoing calls to
-// servers should accept a Context.  The chain of function calls between must
+// servers should accept a Context. The chain of function calls between must
 // propagate the Context, optionally replacing it with a modified copy created
 // using WithDeadline, WithTimeout, WithCancel, or WithValue.
 //
@@ -16,14 +16,14 @@
 // propagation:
 //
 // Do not store Contexts inside a struct type; instead, pass a Context
-// explicitly to each function that needs it.  The Context should be the first
+// explicitly to each function that needs it. The Context should be the first
 // parameter, typically named ctx:
 //
 // 	func DoSomething(ctx context.Context, arg Arg) error {
 // 		// ... use ctx ...
 // 	}
 //
-// Do not pass a nil Context, even if a function permits it.  Pass context.TODO
+// Do not pass a nil Context, even if a function permits it. Pass context.TODO
 // if you are unsure about which Context to use.
 //
 // Use context Values only for request-scoped data that transits processes and
@@ -44,13 +44,13 @@ import "time"
 // Context's methods may be called by multiple goroutines simultaneously.
 type Context interface {
 	// Deadline returns the time when work done on behalf of this context
-	// should be canceled.  Deadline returns ok==false when no deadline is
-	// set.  Successive calls to Deadline return the same results.
+	// should be canceled. Deadline returns ok==false when no deadline is
+	// set. Successive calls to Deadline return the same results.
 	Deadline() (deadline time.Time, ok bool)
 
 	// Done returns a channel that's closed when work done on behalf of this
-	// context should be canceled.  Done may return nil if this context can
-	// never be canceled.  Successive calls to Done return the same value.
+	// context should be canceled. Done may return nil if this context can
+	// never be canceled. Successive calls to Done return the same value.
 	//
 	// WithCancel arranges for Done to be closed when cancel is called;
 	// WithDeadline arranges for Done to be closed when the deadline
@@ -79,24 +79,24 @@ type Context interface {
 	// a Done channel for cancelation.
 	Done() <-chan struct{}
 
-	// Err returns a non-nil error value after Done is closed.  Err returns
+	// Err returns a non-nil error value after Done is closed. Err returns
 	// Canceled if the context was canceled or DeadlineExceeded if the
-	// context's deadline passed.  No other values for Err are defined.
+	// context's deadline passed. No other values for Err are defined.
 	// After Done is closed, successive calls to Err return the same value.
 	Err() error
 
 	// Value returns the value associated with this context for key, or nil
-	// if no value is associated with key.  Successive calls to Value with
+	// if no value is associated with key. Successive calls to Value with
 	// the same key returns the same result.
 	//
 	// Use context values only for request-scoped data that transits
 	// processes and API boundaries, not for passing optional parameters to
 	// functions.
 	//
-	// A key identifies a specific value in a Context.  Functions that wish
+	// A key identifies a specific value in a Context. Functions that wish
 	// to store values in Context typically allocate a key in a global
 	// variable then use that key as the argument to context.WithValue and
-	// Context.Value.  A key can be any type that supports equality;
+	// Context.Value. A key can be any type that supports equality;
 	// packages should define keys as an unexported type to avoid
 	// collisions.
 	//
@@ -115,7 +115,7 @@ type Context interface {
 	// 	// This prevents collisions with keys defined in other packages.
 	// 	type key int
 	//
-	// 	// userKey is the key for user.User values in Contexts.  It is
+	// 	// userKey is the key for user.User values in Contexts. It is
 	// 	// unexported; clients use user.NewContext and user.FromContext
 	// 	// instead of using this key directly.
 	// 	var userKey key = 0
@@ -134,14 +134,14 @@ type Context interface {
 }
 
 // Background returns a non-nil, empty Context. It is never canceled, has no
-// values, and has no deadline.  It is typically used by the main function,
+// values, and has no deadline. It is typically used by the main function,
 // initialization, and tests, and as the top-level Context for incoming
 // requests.
 func Background() Context {
 	return background
 }
 
-// TODO returns a non-nil, empty Context.  Code should use context.TODO when
+// TODO returns a non-nil, empty Context. Code should use context.TODO when
 // it's unclear which Context to use or it is not yet available (because the
 // surrounding function has not yet been extended to accept a Context
 // parameter).  TODO is recognized by static analysis tools that determine

vendor/golang.org/x/net/context/go17.go

@@ -35,8 +35,8 @@ func WithCancel(parent Context) (ctx Context, cancel CancelFunc) {
 }
 
 // WithDeadline returns a copy of the parent context with the deadline adjusted
-// to be no later than d.  If the parent's deadline is already earlier than d,
-// WithDeadline(parent, d) is semantically equivalent to parent.  The returned
+// to be no later than d. If the parent's deadline is already earlier than d,
+// WithDeadline(parent, d) is semantically equivalent to parent. The returned
 // context's Done channel is closed when the deadline expires, when the returned
 // cancel function is called, or when the parent context's Done channel is
 // closed, whichever happens first.

vendor/golang.org/x/net/context/pre_go17.go

@@ -13,7 +13,7 @@ import (
 	"time"
 )
 
-// An emptyCtx is never canceled, has no values, and has no deadline.  It is not
+// An emptyCtx is never canceled, has no values, and has no deadline. It is not
 // struct{}, since vars of this type must have distinct addresses.
 type emptyCtx int
 
@@ -104,7 +104,7 @@ func propagateCancel(parent Context, child canceler) {
 }
 
 // parentCancelCtx follows a chain of parent references until it finds a
-// *cancelCtx.  This function understands how each of the concrete types in this
+// *cancelCtx. This function understands how each of the concrete types in this
 // package represents its parent.
 func parentCancelCtx(parent Context) (*cancelCtx, bool) {
 	for {
@@ -134,14 +134,14 @@ func removeChild(parent Context, child canceler) {
 	p.mu.Unlock()
 }
 
-// A canceler is a context type that can be canceled directly.  The
+// A canceler is a context type that can be canceled directly. The
 // implementations are *cancelCtx and *timerCtx.
 type canceler interface {
 	cancel(removeFromParent bool, err error)
 	Done() <-chan struct{}
 }
 
-// A cancelCtx can be canceled.  When canceled, it also cancels any children
+// A cancelCtx can be canceled. When canceled, it also cancels any children
 // that implement canceler.
 type cancelCtx struct {
 	Context
@@ -193,8 +193,8 @@ func (c *cancelCtx) cancel(removeFromParent bool, err error) {
 }
 
 // WithDeadline returns a copy of the parent context with the deadline adjusted
-// to be no later than d.  If the parent's deadline is already earlier than d,
-// WithDeadline(parent, d) is semantically equivalent to parent.  The returned
+// to be no later than d. If the parent's deadline is already earlier than d,
+// WithDeadline(parent, d) is semantically equivalent to parent. The returned
 // context's Done channel is closed when the deadline expires, when the returned
 // cancel function is called, or when the parent context's Done channel is
 // closed, whichever happens first.
@@ -226,8 +226,8 @@ func WithDeadline(parent Context, deadline time.Time) (Context, CancelFunc) {
 	return c, func() { c.cancel(true, Canceled) }
 }
 
-// A timerCtx carries a timer and a deadline.  It embeds a cancelCtx to
-// implement Done and Err.  It implements cancel by stopping its timer then
+// A timerCtx carries a timer and a deadline. It embeds a cancelCtx to
+// implement Done and Err. It implements cancel by stopping its timer then
 // delegating to cancelCtx.cancel.
 type timerCtx struct {
 	*cancelCtx
@@ -281,7 +281,7 @@ func WithValue(parent Context, key interface{}, val interface{}) Context {
 	return &valueCtx{parent, key, val}
 }
 
-// A valueCtx carries a key-value pair.  It implements Value for that key and
+// A valueCtx carries a key-value pair. It implements Value for that key and
 // delegates all other calls to the embedded Context.
 type valueCtx struct {
 	Context

vendor/golang.org/x/net/http2/client_conn_pool.go

@@ -247,7 +247,7 @@ func filterOutClientConn(in []*ClientConn, exclude *ClientConn) []*ClientConn {
 }
 
 // noDialClientConnPool is an implementation of http2.ClientConnPool
-// which never dials.  We let the HTTP/1.1 client dial and use its TLS
+// which never dials. We let the HTTP/1.1 client dial and use its TLS
 // connection instead.
 type noDialClientConnPool struct{ *clientConnPool }
 

vendor/golang.org/x/net/http2/databuffer.go

@@ -0,0 +1,146 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package http2
+
+import (
+	"errors"
+	"fmt"
+	"sync"
+)
+
+// Buffer chunks are allocated from a pool to reduce pressure on GC.
+// The maximum wasted space per dataBuffer is 2x the largest size class,
+// which happens when the dataBuffer has multiple chunks and there is
+// one unread byte in both the first and last chunks. We use a few size
+// classes to minimize overheads for servers that typically receive very
+// small request bodies.
+//
+// TODO: Benchmark to determine if the pools are necessary. The GC may have
+// improved enough that we can instead allocate chunks like this:
+// make([]byte, max(16<<10, expectedBytesRemaining))
+var (
+	dataChunkSizeClasses = []int{
+		1 << 10,
+		2 << 10,
+		4 << 10,
+		8 << 10,
+		16 << 10,
+	}
+	dataChunkPools = [...]sync.Pool{
+		{New: func() interface{} { return make([]byte, 1<<10) }},
+		{New: func() interface{} { return make([]byte, 2<<10) }},
+		{New: func() interface{} { return make([]byte, 4<<10) }},
+		{New: func() interface{} { return make([]byte, 8<<10) }},
+		{New: func() interface{} { return make([]byte, 16<<10) }},
+	}
+)
+
+func getDataBufferChunk(size int64) []byte {
+	i := 0
+	for ; i < len(dataChunkSizeClasses)-1; i++ {
+		if size <= int64(dataChunkSizeClasses[i]) {
+			break
+		}
+	}
+	return dataChunkPools[i].Get().([]byte)
+}
+
+func putDataBufferChunk(p []byte) {
+	for i, n := range dataChunkSizeClasses {
+		if len(p) == n {
+			dataChunkPools[i].Put(p)
+			return
+		}
+	}
+	panic(fmt.Sprintf("unexpected buffer len=%v", len(p)))
+}
+
+// dataBuffer is an io.ReadWriter backed by a list of data chunks.
+// Each dataBuffer is used to read DATA frames on a single stream.
+// The buffer is divided into chunks so the server can limit the
+// total memory used by a single connection without limiting the
+// request body size on any single stream.
+type dataBuffer struct {
+	chunks   [][]byte
+	r        int   // next byte to read is chunks[0][r]
+	w        int   // next byte to write is chunks[len(chunks)-1][w]
+	size     int   // total buffered bytes
+	expected int64 // we expect at least this many bytes in future Write calls (ignored if <= 0)
+}
+
+var errReadEmpty = errors.New("read from empty dataBuffer")
+
+// Read copies bytes from the buffer into p.
+// It is an error to read when no data is available.
+func (b *dataBuffer) Read(p []byte) (int, error) {
+	if b.size == 0 {
+		return 0, errReadEmpty
+	}
+	var ntotal int
+	for len(p) > 0 && b.size > 0 {
+		readFrom := b.bytesFromFirstChunk()
+		n := copy(p, readFrom)
+		p = p[n:]
+		ntotal += n
+		b.r += n
+		b.size -= n
+		// If the first chunk has been consumed, advance to the next chunk.
+		if b.r == len(b.chunks[0]) {
+			putDataBufferChunk(b.chunks[0])
+			end := len(b.chunks) - 1
+			copy(b.chunks[:end], b.chunks[1:])
+			b.chunks[end] = nil
+			b.chunks = b.chunks[:end]
+			b.r = 0
+		}
+	}
+	return ntotal, nil
+}
+
+func (b *dataBuffer) bytesFromFirstChunk() []byte {
+	if len(b.chunks) == 1 {
+		return b.chunks[0][b.r:b.w]
+	}
+	return b.chunks[0][b.r:]
+}
+
+// Len returns the number of bytes of the unread portion of the buffer.
+func (b *dataBuffer) Len() int {
+	return b.size
+}
+
+// Write appends p to the buffer.
+func (b *dataBuffer) Write(p []byte) (int, error) {
+	ntotal := len(p)
+	for len(p) > 0 {
+		// If the last chunk is empty, allocate a new chunk. Try to allocate
+		// enough to fully copy p plus any additional bytes we expect to
+		// receive. However, this may allocate less than len(p).
+		want := int64(len(p))
+		if b.expected > want {
+			want = b.expected
+		}
+		chunk := b.lastChunkOrAlloc(want)
+		n := copy(chunk[b.w:], p)
+		p = p[n:]
+		b.w += n
+		b.size += n
+		b.expected -= int64(n)
+	}
+	return ntotal, nil
+}
+
+func (b *dataBuffer) lastChunkOrAlloc(want int64) []byte {
+	if len(b.chunks) != 0 {
+		last := b.chunks[len(b.chunks)-1]
+		if b.w < len(last) {
+			return last
+		}
+	}
+	chunk := getDataBufferChunk(want)
+	b.chunks = append(b.chunks, chunk)
+	b.w = 0
+	return chunk
+}

vendor/golang.org/x/net/http2/errors.go

@@ -64,9 +64,17 @@ func (e ConnectionError) Error() string { return fmt.Sprintf("connection error:
 type StreamError struct {
 	StreamID uint32
 	Code     ErrCode
+	Cause    error // optional additional detail
+}
+
+func streamError(id uint32, code ErrCode) StreamError {
+	return StreamError{StreamID: id, Code: code}
 }
 
 func (e StreamError) Error() string {
+	if e.Cause != nil {
+		return fmt.Sprintf("stream error: stream ID %d; %v; %v", e.StreamID, e.Code, e.Cause)
+	}
 	return fmt.Sprintf("stream error: stream ID %d; %v", e.StreamID, e.Code)
 }
 

vendor/golang.org/x/net/http2/fixed_buffer.go

@@ -1,60 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package http2
-
-import (
-	"errors"
-)
-
-// fixedBuffer is an io.ReadWriter backed by a fixed size buffer.
-// It never allocates, but moves old data as new data is written.
-type fixedBuffer struct {
-	buf  []byte
-	r, w int
-}
-
-var (
-	errReadEmpty = errors.New("read from empty fixedBuffer")
-	errWriteFull = errors.New("write on full fixedBuffer")
-)
-
-// Read copies bytes from the buffer into p.
-// It is an error to read when no data is available.
-func (b *fixedBuffer) Read(p []byte) (n int, err error) {
-	if b.r == b.w {
-		return 0, errReadEmpty
-	}
-	n = copy(p, b.buf[b.r:b.w])
-	b.r += n
-	if b.r == b.w {
-		b.r = 0
-		b.w = 0
-	}
-	return n, nil
-}
-
-// Len returns the number of bytes of the unread portion of the buffer.
-func (b *fixedBuffer) Len() int {
-	return b.w - b.r
-}
-
-// Write copies bytes from p into the buffer.
-// It is an error to write more data than the buffer can hold.
-func (b *fixedBuffer) Write(p []byte) (n int, err error) {
-	// Slide existing data to beginning.
-	if b.r > 0 && len(p) > len(b.buf)-b.w {
-		copy(b.buf, b.buf[b.r:b.w])
-		b.w -= b.r
-		b.r = 0
-	}
-
-	// Write new data.
-	n = copy(b.buf[b.w:], p)
-	b.w += n
-	if n < len(p) {
-		err = errWriteFull
-	}
-	return n, err
-}

vendor/golang.org/x/net/http2/frame.go

@@ -122,7 +122,7 @@ var flagName = map[FrameType]map[Flags]string{
 // a frameParser parses a frame given its FrameHeader and payload
 // bytes. The length of payload will always equal fh.Length (which
 // might be 0).
-type frameParser func(fh FrameHeader, payload []byte) (Frame, error)
+type frameParser func(fc *frameCache, fh FrameHeader, payload []byte) (Frame, error)
 
 var frameParsers = map[FrameType]frameParser{
 	FrameData:         parseDataFrame,
@@ -312,15 +312,19 @@ type Framer struct {
 	MaxHeaderListSize uint32
 
 	// TODO: track which type of frame & with which flags was sent
-	// last.  Then return an error (unless AllowIllegalWrites) if
+	// last. Then return an error (unless AllowIllegalWrites) if
 	// we're in the middle of a header block and a
 	// non-Continuation or Continuation on a different stream is
 	// attempted to be written.
 
-	logReads bool
+	logReads, logWrites bool
 
-	debugFramer    *Framer // only use for logging written writes
-	debugFramerBuf *bytes.Buffer
+	debugFramer       *Framer // only use for logging written writes
+	debugFramerBuf    *bytes.Buffer
+	debugReadLoggerf  func(string, ...interface{})
+	debugWriteLoggerf func(string, ...interface{})
+
+	frameCache *frameCache // nil if frames aren't reused (default)
 }
 
 func (fr *Framer) maxHeaderListSize() uint32 {
@@ -355,7 +359,7 @@ func (f *Framer) endWrite() error {
 		byte(length>>16),
 		byte(length>>8),
 		byte(length))
-	if logFrameWrites {
+	if f.logWrites {
 		f.logWrite()
 	}
 
@@ -378,10 +382,10 @@ func (f *Framer) logWrite() {
 	f.debugFramerBuf.Write(f.wbuf)
 	fr, err := f.debugFramer.ReadFrame()
 	if err != nil {
-		log.Printf("http2: Framer %p: failed to decode just-written frame", f)
+		f.debugWriteLoggerf("http2: Framer %p: failed to decode just-written frame", f)
 		return
 	}
-	log.Printf("http2: Framer %p: wrote %v", f, summarizeFrame(fr))
+	f.debugWriteLoggerf("http2: Framer %p: wrote %v", f, summarizeFrame(fr))
 }
 
 func (f *Framer) writeByte(v byte)     { f.wbuf = append(f.wbuf, v) }
@@ -396,12 +400,36 @@ const (
 	maxFrameSize    = 1<<24 - 1
 )
 
+// SetReuseFrames allows the Framer to reuse Frames.
+// If called on a Framer, Frames returned by calls to ReadFrame are only
+// valid until the next call to ReadFrame.
+func (fr *Framer) SetReuseFrames() {
+	if fr.frameCache != nil {
+		return
+	}
+	fr.frameCache = &frameCache{}
+}
+
+type frameCache struct {
+	dataFrame DataFrame
+}
+
+func (fc *frameCache) getDataFrame() *DataFrame {
+	if fc == nil {
+		return &DataFrame{}
+	}
+	return &fc.dataFrame
+}
+
 // NewFramer returns a Framer that writes frames to w and reads them from r.
 func NewFramer(w io.Writer, r io.Reader) *Framer {
 	fr := &Framer{
-		w:        w,
-		r:        r,
-		logReads: logFrameReads,
+		w:                 w,
+		r:                 r,
+		logReads:          logFrameReads,
+		logWrites:         logFrameWrites,
+		debugReadLoggerf:  log.Printf,
+		debugWriteLoggerf: log.Printf,
 	}
 	fr.getReadBuf = func(size uint32) []byte {
 		if cap(fr.readBuf) >= int(size) {
@@ -472,7 +500,7 @@ func (fr *Framer) ReadFrame() (Frame, error) {
 	if _, err := io.ReadFull(fr.r, payload); err != nil {
 		return nil, err
 	}
-	f, err := typeFrameParser(fh.Type)(fh, payload)
+	f, err := typeFrameParser(fh.Type)(fr.frameCache, fh, payload)
 	if err != nil {
 		if ce, ok := err.(connError); ok {
 			return nil, fr.connError(ce.Code, ce.Reason)
@@ -483,7 +511,7 @@ func (fr *Framer) ReadFrame() (Frame, error) {
 		return nil, err
 	}
 	if fr.logReads {
-		log.Printf("http2: Framer %p: read %v", fr, summarizeFrame(f))
+		fr.debugReadLoggerf("http2: Framer %p: read %v", fr, summarizeFrame(f))
 	}
 	if fh.Type == FrameHeaders && fr.ReadMetaHeaders != nil {
 		return fr.readMetaFrame(f.(*HeadersFrame))
@@ -560,7 +588,7 @@ func (f *DataFrame) Data() []byte {
 	return f.data
 }
 
-func parseDataFrame(fh FrameHeader, payload []byte) (Frame, error) {
+func parseDataFrame(fc *frameCache, fh FrameHeader, payload []byte) (Frame, error) {
 	if fh.StreamID == 0 {
 		// DATA frames MUST be associated with a stream. If a
 		// DATA frame is received whose stream identifier
@@ -569,9 +597,9 @@ func parseDataFrame(fh FrameHeader, payload []byte) (Frame, error) {
 		// PROTOCOL_ERROR.
 		return nil, connError{ErrCodeProtocol, "DATA frame with stream ID 0"}
 	}
-	f := &DataFrame{
-		FrameHeader: fh,
-	}
+	f := fc.getDataFrame()
+	f.FrameHeader = fh
+
 	var padSize byte
 	if fh.Flags.Has(FlagDataPadded) {
 		var err error
@@ -594,6 +622,8 @@ func parseDataFrame(fh FrameHeader, payload []byte) (Frame, error) {
 var (
 	errStreamID    = errors.New("invalid stream ID")
 	errDepStreamID = errors.New("invalid dependent stream ID")
+	errPadLength   = errors.New("pad length too large")
+	errPadBytes    = errors.New("padding bytes must all be zeros unless AllowIllegalWrites is enabled")
 )
 
 func validStreamIDOrZero(streamID uint32) bool {
@@ -607,18 +637,51 @@ func validStreamID(streamID uint32) bool {
 // WriteData writes a DATA frame.
 //
 // It will perform exactly one Write to the underlying Writer.
-// It is the caller's responsibility to not call other Write methods concurrently.
+// It is the caller's responsibility not to violate the maximum frame size
+// and to not call other Write methods concurrently.
 func (f *Framer) WriteData(streamID uint32, endStream bool, data []byte) error {
-	// TODO: ignoring padding for now. will add when somebody cares.
+	return f.WriteDataPadded(streamID, endStream, data, nil)
+}
+
+// WriteData writes a DATA frame with optional padding.
+//
+// If pad is nil, the padding bit is not sent.
+// The length of pad must not exceed 255 bytes.
+// The bytes of pad must all be zero, unless f.AllowIllegalWrites is set.
+//
+// It will perform exactly one Write to the underlying Writer.
+// It is the caller's responsibility not to violate the maximum frame size
+// and to not call other Write methods concurrently.
+func (f *Framer) WriteDataPadded(streamID uint32, endStream bool, data, pad []byte) error {
 	if !validStreamID(streamID) && !f.AllowIllegalWrites {
 		return errStreamID
 	}
+	if len(pad) > 0 {
+		if len(pad) > 255 {
+			return errPadLength
+		}
+		if !f.AllowIllegalWrites {
+			for _, b := range pad {
+				if b != 0 {
+					// "Padding octets MUST be set to zero when sending."
+					return errPadBytes
+				}
+			}
+		}
+	}
 	var flags Flags
 	if endStream {
 		flags |= FlagDataEndStream
 	}
+	if pad != nil {
+		flags |= FlagDataPadded
+	}
 	f.startWrite(FrameData, flags, streamID)
+	if pad != nil {
+		f.wbuf = append(f.wbuf, byte(len(pad)))
+	}
 	f.wbuf = append(f.wbuf, data...)
+	f.wbuf = append(f.wbuf, pad...)
 	return f.endWrite()
 }
 
@@ -632,10 +695,10 @@ type SettingsFrame struct {
 	p []byte
 }
 
-func parseSettingsFrame(fh FrameHeader, p []byte) (Frame, error) {
+func parseSettingsFrame(_ *frameCache, fh FrameHeader, p []byte) (Frame, error) {
 	if fh.Flags.Has(FlagSettingsAck) && fh.Length > 0 {
 		// When this (ACK 0x1) bit is set, the payload of the
-		// SETTINGS frame MUST be empty.  Receipt of a
+		// SETTINGS frame MUST be empty. Receipt of a
 		// SETTINGS frame with the ACK flag set and a length
 		// field value other than 0 MUST be treated as a
 		// connection error (Section 5.4.1) of type
@@ -644,7 +707,7 @@ func parseSettingsFrame(fh FrameHeader, p []byte) (Frame, error) {
 	}
 	if fh.StreamID != 0 {
 		// SETTINGS frames always apply to a connection,
-		// never a single stream.  The stream identifier for a
+		// never a single stream. The stream identifier for a
 		// SETTINGS frame MUST be zero (0x0).  If an endpoint
 		// receives a SETTINGS frame whose stream identifier
 		// field is anything other than 0x0, the endpoint MUST
@@ -714,7 +777,7 @@ func (f *Framer) WriteSettings(settings ...Setting) error {
 	return f.endWrite()
 }
 
-// WriteSettings writes an empty SETTINGS frame with the ACK bit set.
+// WriteSettingsAck writes an empty SETTINGS frame with the ACK bit set.
 //
 // It will perform exactly one Write to the underlying Writer.
 // It is the caller's responsibility to not call other Write methods concurrently.
@@ -734,7 +797,7 @@ type PingFrame struct {
 
 func (f *PingFrame) IsAck() bool { return f.Flags.Has(FlagPingAck) }
 
-func parsePingFrame(fh FrameHeader, payload []byte) (Frame, error) {
+func parsePingFrame(_ *frameCache, fh FrameHeader, payload []byte) (Frame, error) {
 	if len(payload) != 8 {
 		return nil, ConnectionError(ErrCodeFrameSize)
 	}
@@ -774,7 +837,7 @@ func (f *GoAwayFrame) DebugData() []byte {
 	return f.debugData
 }
 
-func parseGoAwayFrame(fh FrameHeader, p []byte) (Frame, error) {
+func parseGoAwayFrame(_ *frameCache, fh FrameHeader, p []byte) (Frame, error) {
 	if fh.StreamID != 0 {
 		return nil, ConnectionError(ErrCodeProtocol)
 	}
@@ -814,7 +877,7 @@ func (f *UnknownFrame) Payload() []byte {
 	return f.p
 }
 
-func parseUnknownFrame(fh FrameHeader, p []byte) (Frame, error) {
+func parseUnknownFrame(_ *frameCache, fh FrameHeader, p []byte) (Frame, error) {
 	return &UnknownFrame{fh, p}, nil
 }
 
@@ -825,7 +888,7 @@ type WindowUpdateFrame struct {
 	Increment uint32 // never read with high bit set
 }
 
-func parseWindowUpdateFrame(fh FrameHeader, p []byte) (Frame, error) {
+func parseWindowUpdateFrame(_ *frameCache, fh FrameHeader, p []byte) (Frame, error) {
 	if len(p) != 4 {
 		return nil, ConnectionError(ErrCodeFrameSize)
 	}
@@ -840,7 +903,7 @@ func parseWindowUpdateFrame(fh FrameHeader, p []byte) (Frame, error) {
 		if fh.StreamID == 0 {
 			return nil, ConnectionError(ErrCodeProtocol)
 		}
-		return nil, StreamError{fh.StreamID, ErrCodeProtocol}
+		return nil, streamError(fh.StreamID, ErrCodeProtocol)
 	}
 	return &WindowUpdateFrame{
 		FrameHeader: fh,
@@ -890,12 +953,12 @@ func (f *HeadersFrame) HasPriority() bool {
 	return f.FrameHeader.Flags.Has(FlagHeadersPriority)
 }
 
-func parseHeadersFrame(fh FrameHeader, p []byte) (_ Frame, err error) {
+func parseHeadersFrame(_ *frameCache, fh FrameHeader, p []byte) (_ Frame, err error) {
 	hf := &HeadersFrame{
 		FrameHeader: fh,
 	}
 	if fh.StreamID == 0 {
-		// HEADERS frames MUST be associated with a stream.  If a HEADERS frame
+		// HEADERS frames MUST be associated with a stream. If a HEADERS frame
 		// is received whose stream identifier field is 0x0, the recipient MUST
 		// respond with a connection error (Section 5.4.1) of type
 		// PROTOCOL_ERROR.
@@ -921,7 +984,7 @@ func parseHeadersFrame(fh FrameHeader, p []byte) (_ Frame, err error) {
 		}
 	}
 	if len(p)-int(padLength) <= 0 {
-		return nil, StreamError{fh.StreamID, ErrCodeProtocol}
+		return nil, streamError(fh.StreamID, ErrCodeProtocol)
 	}
 	hf.headerFragBuf = p[:len(p)-int(padLength)]
 	return hf, nil
@@ -1017,7 +1080,7 @@ type PriorityParam struct {
 	Exclusive bool
 
 	// Weight is the stream's zero-indexed weight. It should be
-	// set together with StreamDep, or neither should be set.  Per
+	// set together with StreamDep, or neither should be set. Per
 	// the spec, "Add one to the value to obtain a weight between
 	// 1 and 256."
 	Weight uint8
@@ -1027,7 +1090,7 @@ func (p PriorityParam) IsZero() bool {
 	return p == PriorityParam{}
 }
 
-func parsePriorityFrame(fh FrameHeader, payload []byte) (Frame, error) {
+func parsePriorityFrame(_ *frameCache, fh FrameHeader, payload []byte) (Frame, error) {
 	if fh.StreamID == 0 {
 		return nil, connError{ErrCodeProtocol, "PRIORITY frame with stream ID 0"}
 	}
@@ -1074,7 +1137,7 @@ type RSTStreamFrame struct {
 	ErrCode ErrCode
 }
 
-func parseRSTStreamFrame(fh FrameHeader, p []byte) (Frame, error) {
+func parseRSTStreamFrame(_ *frameCache, fh FrameHeader, p []byte) (Frame, error) {
 	if len(p) != 4 {
 		return nil, ConnectionError(ErrCodeFrameSize)
 	}
@@ -1104,7 +1167,7 @@ type ContinuationFrame struct {
 	headerFragBuf []byte
 }
 
-func parseContinuationFrame(fh FrameHeader, p []byte) (Frame, error) {
+func parseContinuationFrame(_ *frameCache, fh FrameHeader, p []byte) (Frame, error) {
 	if fh.StreamID == 0 {
 		return nil, connError{ErrCodeProtocol, "CONTINUATION frame with stream ID 0"}
 	}
@@ -1154,7 +1217,7 @@ func (f *PushPromiseFrame) HeadersEnded() bool {
 	return f.FrameHeader.Flags.Has(FlagPushPromiseEndHeaders)
 }
 
-func parsePushPromise(fh FrameHeader, p []byte) (_ Frame, err error) {
+func parsePushPromise(_ *frameCache, fh FrameHeader, p []byte) (_ Frame, err error) {
 	pp := &PushPromiseFrame{
 		FrameHeader: fh,
 	}
@@ -1396,6 +1459,9 @@ func (fr *Framer) readMetaFrame(hf *HeadersFrame) (*MetaHeadersFrame, error) {
 	hdec.SetEmitEnabled(true)
 	hdec.SetMaxStringLength(fr.maxHeaderStringLen())
 	hdec.SetEmitFunc(func(hf hpack.HeaderField) {
+		if VerboseLogs && fr.logReads {
+			fr.debugReadLoggerf("http2: decoded hpack field %+v", hf)
+		}
 		if !httplex.ValidHeaderFieldValue(hf.Value) {
 			invalid = headerFieldValueError(hf.Value)
 		}
@@ -1454,11 +1520,17 @@ func (fr *Framer) readMetaFrame(hf *HeadersFrame) (*MetaHeadersFrame, error) {
 	}
 	if invalid != nil {
 		fr.errDetail = invalid
-		return nil, StreamError{mh.StreamID, ErrCodeProtocol}
+		if VerboseLogs {
+			log.Printf("http2: invalid header: %v", invalid)
+		}
+		return nil, StreamError{mh.StreamID, ErrCodeProtocol, invalid}
 	}
 	if err := mh.checkPseudos(); err != nil {
 		fr.errDetail = err
-		return nil, StreamError{mh.StreamID, ErrCodeProtocol}
+		if VerboseLogs {
+			log.Printf("http2: invalid pseudo headers: %v", err)
+		}
+		return nil, StreamError{mh.StreamID, ErrCodeProtocol, err}
 	}
 	return mh, nil
 }

vendor/golang.org/x/net/http2/go17.go

@@ -39,6 +39,13 @@ type clientTrace httptrace.ClientTrace
 
 func reqContext(r *http.Request) context.Context { return r.Context() }
 
+func (t *Transport) idleConnTimeout() time.Duration {
+	if t.t1 != nil {
+		return t.t1.IdleConnTimeout
+	}
+	return 0
+}
+
 func setResponseUncompressed(res *http.Response) { res.Uncompressed = true }
 
 func traceGotConn(req *http.Request, cc *ClientConn) {
@@ -92,3 +99,8 @@ func requestTrace(req *http.Request) *clientTrace {
 	trace := httptrace.ContextClientTrace(req.Context())
 	return (*clientTrace)(trace)
 }
+
+// Ping sends a PING frame to the server and waits for the ack.
+func (cc *ClientConn) Ping(ctx context.Context) error {
+	return cc.ping(ctx)
+}

vendor/golang.org/x/net/http2/go17_not18.go

@@ -0,0 +1,36 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.7,!go1.8
+
+package http2
+
+import "crypto/tls"
+
+// temporary copy of Go 1.7's private tls.Config.clone:
+func cloneTLSConfig(c *tls.Config) *tls.Config {
+	return &tls.Config{
+		Rand:                        c.Rand,
+		Time:                        c.Time,
+		Certificates:                c.Certificates,
+		NameToCertificate:           c.NameToCertificate,
+		GetCertificate:              c.GetCertificate,
+		RootCAs:                     c.RootCAs,
+		NextProtos:                  c.NextProtos,
+		ServerName:                  c.ServerName,
+		ClientAuth:                  c.ClientAuth,
+		ClientCAs:                   c.ClientCAs,
+		InsecureSkipVerify:          c.InsecureSkipVerify,
+		CipherSuites:                c.CipherSuites,
+		PreferServerCipherSuites:    c.PreferServerCipherSuites,
+		SessionTicketsDisabled:      c.SessionTicketsDisabled,
+		SessionTicketKey:            c.SessionTicketKey,
+		ClientSessionCache:          c.ClientSessionCache,
+		MinVersion:                  c.MinVersion,
+		MaxVersion:                  c.MaxVersion,
+		CurvePreferences:            c.CurvePreferences,
+		DynamicRecordSizingDisabled: c.DynamicRecordSizingDisabled,
+		Renegotiation:               c.Renegotiation,
+	}
+}

vendor/golang.org/x/net/http2/go18.go

@@ -0,0 +1,54 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.8
+
+package http2
+
+import (
+	"crypto/tls"
+	"io"
+	"net/http"
+)
+
+func cloneTLSConfig(c *tls.Config) *tls.Config {
+	c2 := c.Clone()
+	c2.GetClientCertificate = c.GetClientCertificate // golang.org/issue/19264
+	return c2
+}
+
+var _ http.Pusher = (*responseWriter)(nil)
+
+// Push implements http.Pusher.
+func (w *responseWriter) Push(target string, opts *http.PushOptions) error {
+	internalOpts := pushOptions{}
+	if opts != nil {
+		internalOpts.Method = opts.Method
+		internalOpts.Header = opts.Header
+	}
+	return w.push(target, internalOpts)
+}
+
+func configureServer18(h1 *http.Server, h2 *Server) error {
+	if h2.IdleTimeout == 0 {
+		if h1.IdleTimeout != 0 {
+			h2.IdleTimeout = h1.IdleTimeout
+		} else {
+			h2.IdleTimeout = h1.ReadTimeout
+		}
+	}
+	return nil
+}
+
+func shouldLogPanic(panicValue interface{}) bool {
+	return panicValue != nil && panicValue != http.ErrAbortHandler
+}
+
+func reqGetBody(req *http.Request) func() (io.ReadCloser, error) {
+	return req.GetBody
+}
+
+func reqBodyIsNoBody(body io.ReadCloser) bool {
+	return body == http.NoBody
+}

vendor/golang.org/x/net/http2/hpack/encode.go

@@ -39,13 +39,14 @@ func NewEncoder(w io.Writer) *Encoder {
 		tableSizeUpdate: false,
 		w:               w,
 	}
+	e.dynTab.table.init()
 	e.dynTab.setMaxSize(initialHeaderTableSize)
 	return e
 }
 
 // WriteField encodes f into a single Write to e's underlying Writer.
 // This function may also produce bytes for "Header Table Size Update"
-// if necessary.  If produced, it is done before encoding f.
+// if necessary. If produced, it is done before encoding f.
 func (e *Encoder) WriteField(f HeaderField) error {
 	e.buf = e.buf[:0]
 
@@ -88,29 +89,17 @@ func (e *Encoder) WriteField(f HeaderField) error {
 // only name matches, i points to that index and nameValueMatch
 // becomes false.
 func (e *Encoder) searchTable(f HeaderField) (i uint64, nameValueMatch bool) {
-	for idx, hf := range staticTable {
-		if !constantTimeStringCompare(hf.Name, f.Name) {
-			continue
-		}
-		if i == 0 {
-			i = uint64(idx + 1)
-		}
-		if f.Sensitive {
-			continue
-		}
-		if !constantTimeStringCompare(hf.Value, f.Value) {
-			continue
-		}
-		i = uint64(idx + 1)
-		nameValueMatch = true
-		return
+	i, nameValueMatch = staticTable.search(f)
+	if nameValueMatch {
+		return i, true
 	}
 
-	j, nameValueMatch := e.dynTab.search(f)
+	j, nameValueMatch := e.dynTab.table.search(f)
 	if nameValueMatch || (i == 0 && j != 0) {
-		i = j + uint64(len(staticTable))
+		return j + uint64(staticTable.len()), nameValueMatch
 	}
-	return
+
+	return i, false
 }
 
 // SetMaxDynamicTableSize changes the dynamic header table size to v.

vendor/golang.org/x/net/http2/hpack/hpack.go

@@ -57,11 +57,11 @@ func (hf HeaderField) String() string {
 	return fmt.Sprintf("header field %q = %q%s", hf.Name, hf.Value, suffix)
 }
 
-// Size returns the size of an entry per RFC 7540 section 5.2.
+// Size returns the size of an entry per RFC 7541 section 4.1.
 func (hf HeaderField) Size() uint32 {
 	// http://http2.github.io/http2-spec/compression.html#rfc.section.4.1
 	// "The size of the dynamic table is the sum of the size of
-	// its entries.  The size of an entry is the sum of its name's
+	// its entries. The size of an entry is the sum of its name's
 	// length in octets (as defined in Section 5.2), its value's
 	// length in octets (see Section 5.2), plus 32.  The size of
 	// an entry is calculated using the length of the name and
@@ -102,6 +102,7 @@ func NewDecoder(maxDynamicTableSize uint32, emitFunc func(f HeaderField)) *Decod
 		emit:        emitFunc,
 		emitEnabled: true,
 	}
+	d.dynTab.table.init()
 	d.dynTab.allowedMaxSize = maxDynamicTableSize
 	d.dynTab.setMaxSize(maxDynamicTableSize)
 	return d
@@ -154,12 +155,9 @@ func (d *Decoder) SetAllowedMaxDynamicTableSize(v uint32) {
 }
 
 type dynamicTable struct {
-	// ents is the FIFO described at
 	// http://http2.github.io/http2-spec/compression.html#rfc.section.2.3.2
-	// The newest (low index) is append at the end, and items are
-	// evicted from the front.
-	ents           []HeaderField
-	size           uint32
+	table          headerFieldTable
+	size           uint32 // in bytes
 	maxSize        uint32 // current maxSize
 	allowedMaxSize uint32 // maxSize may go up to this, inclusive
 }
@@ -169,95 +167,45 @@ func (dt *dynamicTable) setMaxSize(v uint32) {
 	dt.evict()
 }
 
-// TODO: change dynamicTable to be a struct with a slice and a size int field,
-// per http://http2.github.io/http2-spec/compression.html#rfc.section.4.1:
-//
-//
-// Then make add increment the size. maybe the max size should move from Decoder to
-// dynamicTable and add should return an ok bool if there was enough space.
-//
-// Later we'll need a remove operation on dynamicTable.
-
 func (dt *dynamicTable) add(f HeaderField) {
-	dt.ents = append(dt.ents, f)
+	dt.table.addEntry(f)
 	dt.size += f.Size()
 	dt.evict()
 }
 
-// If we're too big, evict old stuff (front of the slice)
+// If we're too big, evict old stuff.
 func (dt *dynamicTable) evict() {
-	base := dt.ents // keep base pointer of slice
-	for dt.size > dt.maxSize {
-		dt.size -= dt.ents[0].Size()
-		dt.ents = dt.ents[1:]
+	var n int
+	for dt.size > dt.maxSize && n < dt.table.len() {
+		dt.size -= dt.table.ents[n].Size()
+		n++
 	}
-
-	// Shift slice contents down if we evicted things.
-	if len(dt.ents) != len(base) {
-		copy(base, dt.ents)
-		dt.ents = base[:len(dt.ents)]
-	}
-}
-
-// constantTimeStringCompare compares string a and b in a constant
-// time manner.
-func constantTimeStringCompare(a, b string) bool {
-	if len(a) != len(b) {
-		return false
-	}
-
-	c := byte(0)
-
-	for i := 0; i < len(a); i++ {
-		c |= a[i] ^ b[i]
-	}
-
-	return c == 0
-}
-
-// Search searches f in the table. The return value i is 0 if there is
-// no name match. If there is name match or name/value match, i is the
-// index of that entry (1-based). If both name and value match,
-// nameValueMatch becomes true.
-func (dt *dynamicTable) search(f HeaderField) (i uint64, nameValueMatch bool) {
-	l := len(dt.ents)
-	for j := l - 1; j >= 0; j-- {
-		ent := dt.ents[j]
-		if !constantTimeStringCompare(ent.Name, f.Name) {
-			continue
-		}
-		if i == 0 {
-			i = uint64(l - j)
-		}
-		if f.Sensitive {
-			continue
-		}
-		if !constantTimeStringCompare(ent.Value, f.Value) {
-			continue
-		}
-		i = uint64(l - j)
-		nameValueMatch = true
-		return
-	}
-	return
+	dt.table.evictOldest(n)
 }
 
 func (d *Decoder) maxTableIndex() int {
-	return len(d.dynTab.ents) + len(staticTable)
+	// This should never overflow. RFC 7540 Section 6.5.2 limits the size of
+	// the dynamic table to 2^32 bytes, where each entry will occupy more than
+	// one byte. Further, the staticTable has a fixed, small length.
+	return d.dynTab.table.len() + staticTable.len()
 }
 
 func (d *Decoder) at(i uint64) (hf HeaderField, ok bool) {
-	if i < 1 {
+	// See Section 2.3.3.
+	if i == 0 {
 		return
 	}
+	if i <= uint64(staticTable.len()) {
+		return staticTable.ents[i-1], true
+	}
 	if i > uint64(d.maxTableIndex()) {
 		return
 	}
-	if i <= uint64(len(staticTable)) {
-		return staticTable[i-1], true
-	}
-	dents := d.dynTab.ents
-	return dents[len(dents)-(int(i)-len(staticTable))], true
+	// In the dynamic table, newer entries have lower indices.
+	// However, dt.ents[0] is the oldest entry. Hence, dt.ents is
+	// the reversed dynamic table.
+	dt := d.dynTab.table
+	return dt.ents[dt.len()-(int(i)-staticTable.len())], true
 }
 
 // Decode decodes an entire block.
@@ -307,7 +255,7 @@ func (d *Decoder) Write(p []byte) (n int, err error) {
 		err = d.parseHeaderFieldRepr()
 		if err == errNeedMore {
 			// Extra paranoia, making sure saveBuf won't
-			// get too large.  All the varint and string
+			// get too large. All the varint and string
 			// reading code earlier should already catch
 			// overlong things and return ErrStringLength,
 			// but keep this as a last resort.

vendor/golang.org/x/net/http2/hpack/tables.go

@@ -4,73 +4,199 @@
 
 package hpack
 
+import (
+	"fmt"
+)
+
+// headerFieldTable implements a list of HeaderFields.
+// This is used to implement the static and dynamic tables.
+type headerFieldTable struct {
+	// For static tables, entries are never evicted.
+	//
+	// For dynamic tables, entries are evicted from ents[0] and added to the end.
+	// Each entry has a unique id that starts at one and increments for each
+	// entry that is added. This unique id is stable across evictions, meaning
+	// it can be used as a pointer to a specific entry. As in hpack, unique ids
+	// are 1-based. The unique id for ents[k] is k + evictCount + 1.
+	//
+	// Zero is not a valid unique id.
+	//
+	// evictCount should not overflow in any remotely practical situation. In
+	// practice, we will have one dynamic table per HTTP/2 connection. If we
+	// assume a very powerful server that handles 1M QPS per connection and each
+	// request adds (then evicts) 100 entries from the table, it would still take
+	// 2M years for evictCount to overflow.
+	ents       []HeaderField
+	evictCount uint64
+
+	// byName maps a HeaderField name to the unique id of the newest entry with
+	// the same name. See above for a definition of "unique id".
+	byName map[string]uint64
+
+	// byNameValue maps a HeaderField name/value pair to the unique id of the newest
+	// entry with the same name and value. See above for a definition of "unique id".
+	byNameValue map[pairNameValue]uint64
+}
+
+type pairNameValue struct {
+	name, value string
+}
+
+func (t *headerFieldTable) init() {
+	t.byName = make(map[string]uint64)
+	t.byNameValue = make(map[pairNameValue]uint64)
+}
+
+// len reports the number of entries in the table.
+func (t *headerFieldTable) len() int {
+	return len(t.ents)
+}
+
+// addEntry adds a new entry.
+func (t *headerFieldTable) addEntry(f HeaderField) {
+	id := uint64(t.len()) + t.evictCount + 1
+	t.byName[f.Name] = id
+	t.byNameValue[pairNameValue{f.Name, f.Value}] = id
+	t.ents = append(t.ents, f)
+}
+
+// evictOldest evicts the n oldest entries in the table.
+func (t *headerFieldTable) evictOldest(n int) {
+	if n > t.len() {
+		panic(fmt.Sprintf("evictOldest(%v) on table with %v entries", n, t.len()))
+	}
+	for k := 0; k < n; k++ {
+		f := t.ents[k]
+		id := t.evictCount + uint64(k) + 1
+		if t.byName[f.Name] == id {
+			delete(t.byName, f.Name)
+		}
+		if p := (pairNameValue{f.Name, f.Value}); t.byNameValue[p] == id {
+			delete(t.byNameValue, p)
+		}
+	}
+	copy(t.ents, t.ents[n:])
+	for k := t.len() - n; k < t.len(); k++ {
+		t.ents[k] = HeaderField{} // so strings can be garbage collected
+	}
+	t.ents = t.ents[:t.len()-n]
+	if t.evictCount+uint64(n) < t.evictCount {
+		panic("evictCount overflow")
+	}
+	t.evictCount += uint64(n)
+}
+
+// search finds f in the table. If there is no match, i is 0.
+// If both name and value match, i is the matched index and nameValueMatch
+// becomes true. If only name matches, i points to that index and
+// nameValueMatch becomes false.
+//
+// The returned index is a 1-based HPACK index. For dynamic tables, HPACK says
+// that index 1 should be the newest entry, but t.ents[0] is the oldest entry,
+// meaning t.ents is reversed for dynamic tables. Hence, when t is a dynamic
+// table, the return value i actually refers to the entry t.ents[t.len()-i].
+//
+// All tables are assumed to be a dynamic tables except for the global
+// staticTable pointer.
+//
+// See Section 2.3.3.
+func (t *headerFieldTable) search(f HeaderField) (i uint64, nameValueMatch bool) {
+	if !f.Sensitive {
+		if id := t.byNameValue[pairNameValue{f.Name, f.Value}]; id != 0 {
+			return t.idToIndex(id), true
+		}
+	}
+	if id := t.byName[f.Name]; id != 0 {
+		return t.idToIndex(id), false
+	}
+	return 0, false
+}
+
+// idToIndex converts a unique id to an HPACK index.
+// See Section 2.3.3.
+func (t *headerFieldTable) idToIndex(id uint64) uint64 {
+	if id <= t.evictCount {
+		panic(fmt.Sprintf("id (%v) <= evictCount (%v)", id, t.evictCount))
+	}
+	k := id - t.evictCount - 1 // convert id to an index t.ents[k]
+	if t != staticTable {
+		return uint64(t.len()) - k // dynamic table
+	}
+	return k + 1
+}
+
 func pair(name, value string) HeaderField {
 	return HeaderField{Name: name, Value: value}
 }
 
 // http://tools.ietf.org/html/draft-ietf-httpbis-header-compression-07#appendix-B
-var staticTable = [...]HeaderField{
-	pair(":authority", ""), // index 1 (1-based)
-	pair(":method", "GET"),
-	pair(":method", "POST"),
-	pair(":path", "/"),
-	pair(":path", "/index.html"),
-	pair(":scheme", "http"),
-	pair(":scheme", "https"),
-	pair(":status", "200"),
-	pair(":status", "204"),
-	pair(":status", "206"),
-	pair(":status", "304"),
-	pair(":status", "400"),
-	pair(":status", "404"),
-	pair(":status", "500"),
-	pair("accept-charset", ""),
-	pair("accept-encoding", "gzip, deflate"),
-	pair("accept-language", ""),
-	pair("accept-ranges", ""),
-	pair("accept", ""),
-	pair("access-control-allow-origin", ""),
-	pair("age", ""),
-	pair("allow", ""),
-	pair("authorization", ""),
-	pair("cache-control", ""),
-	pair("content-disposition", ""),
-	pair("content-encoding", ""),
-	pair("content-language", ""),
-	pair("content-length", ""),
-	pair("content-location", ""),
-	pair("content-range", ""),
-	pair("content-type", ""),
-	pair("cookie", ""),
-	pair("date", ""),
-	pair("etag", ""),
-	pair("expect", ""),
-	pair("expires", ""),
-	pair("from", ""),
-	pair("host", ""),
-	pair("if-match", ""),
-	pair("if-modified-since", ""),
-	pair("if-none-match", ""),
-	pair("if-range", ""),
-	pair("if-unmodified-since", ""),
-	pair("last-modified", ""),
-	pair("link", ""),
-	pair("location", ""),
-	pair("max-forwards", ""),
-	pair("proxy-authenticate", ""),
-	pair("proxy-authorization", ""),
-	pair("range", ""),
-	pair("referer", ""),
-	pair("refresh", ""),
-	pair("retry-after", ""),
-	pair("server", ""),
-	pair("set-cookie", ""),
-	pair("strict-transport-security", ""),
-	pair("transfer-encoding", ""),
-	pair("user-agent", ""),
-	pair("vary", ""),
-	pair("via", ""),
-	pair("www-authenticate", ""),
+var staticTable = newStaticTable()
+
+func newStaticTable() *headerFieldTable {
+	t := &headerFieldTable{}
+	t.init()
+	t.addEntry(pair(":authority", ""))
+	t.addEntry(pair(":method", "GET"))
+	t.addEntry(pair(":method", "POST"))
+	t.addEntry(pair(":path", "/"))
+	t.addEntry(pair(":path", "/index.html"))
+	t.addEntry(pair(":scheme", "http"))
+	t.addEntry(pair(":scheme", "https"))
+	t.addEntry(pair(":status", "200"))
+	t.addEntry(pair(":status", "204"))
+	t.addEntry(pair(":status", "206"))
+	t.addEntry(pair(":status", "304"))
+	t.addEntry(pair(":status", "400"))
+	t.addEntry(pair(":status", "404"))
+	t.addEntry(pair(":status", "500"))
+	t.addEntry(pair("accept-charset", ""))
+	t.addEntry(pair("accept-encoding", "gzip, deflate"))
+	t.addEntry(pair("accept-language", ""))
+	t.addEntry(pair("accept-ranges", ""))
+	t.addEntry(pair("accept", ""))
+	t.addEntry(pair("access-control-allow-origin", ""))
+	t.addEntry(pair("age", ""))
+	t.addEntry(pair("allow", ""))
+	t.addEntry(pair("authorization", ""))
+	t.addEntry(pair("cache-control", ""))
+	t.addEntry(pair("content-disposition", ""))
+	t.addEntry(pair("content-encoding", ""))
+	t.addEntry(pair("content-language", ""))
+	t.addEntry(pair("content-length", ""))
+	t.addEntry(pair("content-location", ""))
+	t.addEntry(pair("content-range", ""))
+	t.addEntry(pair("content-type", ""))
+	t.addEntry(pair("cookie", ""))
+	t.addEntry(pair("date", ""))
+	t.addEntry(pair("etag", ""))
+	t.addEntry(pair("expect", ""))
+	t.addEntry(pair("expires", ""))
+	t.addEntry(pair("from", ""))
+	t.addEntry(pair("host", ""))
+	t.addEntry(pair("if-match", ""))
+	t.addEntry(pair("if-modified-since", ""))
+	t.addEntry(pair("if-none-match", ""))
+	t.addEntry(pair("if-range", ""))
+	t.addEntry(pair("if-unmodified-since", ""))
+	t.addEntry(pair("last-modified", ""))
+	t.addEntry(pair("link", ""))
+	t.addEntry(pair("location", ""))
+	t.addEntry(pair("max-forwards", ""))
+	t.addEntry(pair("proxy-authenticate", ""))
+	t.addEntry(pair("proxy-authorization", ""))
+	t.addEntry(pair("range", ""))
+	t.addEntry(pair("referer", ""))
+	t.addEntry(pair("refresh", ""))
+	t.addEntry(pair("retry-after", ""))
+	t.addEntry(pair("server", ""))
+	t.addEntry(pair("set-cookie", ""))
+	t.addEntry(pair("strict-transport-security", ""))
+	t.addEntry(pair("transfer-encoding", ""))
+	t.addEntry(pair("user-agent", ""))
+	t.addEntry(pair("vary", ""))
+	t.addEntry(pair("via", ""))
+	t.addEntry(pair("www-authenticate", ""))
+	return t
 }
 
 var huffmanCodes = [256]uint32{

vendor/golang.org/x/net/http2/http2.go

@@ -13,7 +13,8 @@
 // See https://http2.github.io/ for more information on HTTP/2.
 //
 // See https://http2.golang.org/ for a test server running this code.
-package http2
+//
+package http2 // import "golang.org/x/net/http2"
 
 import (
 	"bufio"
@@ -35,6 +36,7 @@ var (
 	VerboseLogs    bool
 	logFrameWrites bool
 	logFrameReads  bool
+	inTests        bool
 )
 
 func init() {
@@ -76,13 +78,23 @@ var (
 
 type streamState int
 
+// HTTP/2 stream states.
+//
+// See http://tools.ietf.org/html/rfc7540#section-5.1.
+//
+// For simplicity, the server code merges "reserved (local)" into
+// "half-closed (remote)". This is one less state transition to track.
+// The only downside is that we send PUSH_PROMISEs slightly less
+// liberally than allowable. More discussion here:
+// https://lists.w3.org/Archives/Public/ietf-http-wg/2016JulSep/0599.html
+//
+// "reserved (remote)" is omitted since the client code does not
+// support server push.
 const (
 	stateIdle streamState = iota
 	stateOpen
 	stateHalfClosedLocal
 	stateHalfClosedRemote
-	stateResvLocal
-	stateResvRemote
 	stateClosed
 )
 
@@ -91,8 +103,6 @@ var stateName = [...]string{
 	stateOpen:             "Open",
 	stateHalfClosedLocal:  "HalfClosedLocal",
 	stateHalfClosedRemote: "HalfClosedRemote",
-	stateResvLocal:        "ResvLocal",
-	stateResvRemote:       "ResvRemote",
 	stateClosed:           "Closed",
 }
 
@@ -252,14 +262,27 @@ func newBufferedWriter(w io.Writer) *bufferedWriter {
 	return &bufferedWriter{w: w}
 }
 
+// bufWriterPoolBufferSize is the size of bufio.Writer's
+// buffers created using bufWriterPool.
+//
+// TODO: pick a less arbitrary value? this is a bit under
+// (3 x typical 1500 byte MTU) at least. Other than that,
+// not much thought went into it.
+const bufWriterPoolBufferSize = 4 << 10
+
 var bufWriterPool = sync.Pool{
 	New: func() interface{} {
-		// TODO: pick something better? this is a bit under
-		// (3 x typical 1500 byte MTU) at least.
-		return bufio.NewWriterSize(nil, 4<<10)
+		return bufio.NewWriterSize(nil, bufWriterPoolBufferSize)
 	},
 }
 
+func (w *bufferedWriter) Available() int {
+	if w.bw == nil {
+		return bufWriterPoolBufferSize
+	}
+	return w.bw.Available()
+}
+
 func (w *bufferedWriter) Write(p []byte) (n int, err error) {
 	if w.bw == nil {
 		bw := bufWriterPool.Get().(*bufio.Writer)
@@ -342,10 +365,23 @@ func (s *sorter) Keys(h http.Header) []string {
 }
 
 func (s *sorter) SortStrings(ss []string) {
-	// Our sorter works on s.v, which sorter owners, so
+	// Our sorter works on s.v, which sorter owns, so
 	// stash it away while we sort the user's buffer.
 	save := s.v
 	s.v = ss
 	sort.Sort(s)
 	s.v = save
 }
+
+// validPseudoPath reports whether v is a valid :path pseudo-header
+// value. It must be either:
+//
+//     *) a non-empty string starting with '/', but not with with "//",
+//     *) the string '*', for OPTIONS requests.
+//
+// For now this is only used a quick check for deciding when to clean
+// up Opaque URLs before sending requests from the Transport.
+// See golang.org/issue/16847
+func validPseudoPath(v string) bool {
+	return (len(v) > 0 && v[0] == '/' && (len(v) == 1 || v[1] != '/')) || v == "*"
+}

vendor/golang.org/x/net/http2/not_go17.go

@@ -7,11 +7,16 @@
 package http2
 
 import (
+	"crypto/tls"
 	"net"
 	"net/http"
+	"time"
 )
 
-type contextContext interface{}
+type contextContext interface {
+	Done() <-chan struct{}
+	Err() error
+}
 
 type fakeContext struct{}
 
@@ -49,3 +54,34 @@ func contextWithCancel(ctx contextContext) (_ contextContext, cancel func()) {
 func requestWithContext(req *http.Request, ctx contextContext) *http.Request {
 	return req
 }
+
+// temporary copy of Go 1.6's private tls.Config.clone:
+func cloneTLSConfig(c *tls.Config) *tls.Config {
+	return &tls.Config{
+		Rand:                     c.Rand,
+		Time:                     c.Time,
+		Certificates:             c.Certificates,
+		NameToCertificate:        c.NameToCertificate,
+		GetCertificate:           c.GetCertificate,
+		RootCAs:                  c.RootCAs,
+		NextProtos:               c.NextProtos,
+		ServerName:               c.ServerName,
+		ClientAuth:               c.ClientAuth,
+		ClientCAs:                c.ClientCAs,
+		InsecureSkipVerify:       c.InsecureSkipVerify,
+		CipherSuites:             c.CipherSuites,
+		PreferServerCipherSuites: c.PreferServerCipherSuites,
+		SessionTicketsDisabled:   c.SessionTicketsDisabled,
+		SessionTicketKey:         c.SessionTicketKey,
+		ClientSessionCache:       c.ClientSessionCache,
+		MinVersion:               c.MinVersion,
+		MaxVersion:               c.MaxVersion,
+		CurvePreferences:         c.CurvePreferences,
+	}
+}
+
+func (cc *ClientConn) Ping(ctx contextContext) error {
+	return cc.ping(ctx)
+}
+
+func (t *Transport) idleConnTimeout() time.Duration { return 0 }

vendor/golang.org/x/net/http2/not_go18.go

@@ -0,0 +1,27 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !go1.8
+
+package http2
+
+import (
+	"io"
+	"net/http"
+)
+
+func configureServer18(h1 *http.Server, h2 *Server) error {
+	// No IdleTimeout to sync prior to Go 1.8.
+	return nil
+}
+
+func shouldLogPanic(panicValue interface{}) bool {
+	return panicValue != nil
+}
+
+func reqGetBody(req *http.Request) func() (io.ReadCloser, error) {
+	return nil
+}
+
+func reqBodyIsNoBody(io.ReadCloser) bool { return false }

vendor/golang.org/x/net/http2/pipe.go

@@ -10,7 +10,7 @@ import (
 	"sync"
 )
 
-// pipe is a goroutine-safe io.Reader/io.Writer pair.  It's like
+// pipe is a goroutine-safe io.Reader/io.Writer pair. It's like
 // io.Pipe except there are no PipeReader/PipeWriter halves, and the
 // underlying buffer is an interface. (io.Pipe is always unbuffered)
 type pipe struct {

vendor/golang.org/x/net/http2/transport.go

@@ -10,12 +10,14 @@ import (
 	"bufio"
 	"bytes"
 	"compress/gzip"
+	"crypto/rand"
 	"crypto/tls"
 	"errors"
 	"fmt"
 	"io"
 	"io/ioutil"
 	"log"
+	"math"
 	"net"
 	"net/http"
 	"sort"
@@ -25,6 +27,7 @@ import (
 	"time"
 
 	"golang.org/x/net/http2/hpack"
+	"golang.org/x/net/idna"
 	"golang.org/x/net/lex/httplex"
 )
 
@@ -148,27 +151,32 @@ type ClientConn struct {
 	readerDone chan struct{} // closed on error
 	readerErr  error         // set before readerDone is closed
 
-	mu           sync.Mutex // guards following
-	cond         *sync.Cond // hold mu; broadcast on flow/closed changes
-	flow         flow       // our conn-level flow control quota (cs.flow is per stream)
-	inflow       flow       // peer's conn-level flow control
-	closed       bool
-	goAway       *GoAwayFrame             // if non-nil, the GoAwayFrame we received
-	goAwayDebug  string                   // goAway frame's debug data, retained as a string
-	streams      map[uint32]*clientStream // client-initiated
-	nextStreamID uint32
-	bw           *bufio.Writer
-	br           *bufio.Reader
-	fr           *Framer
-	lastActive   time.Time
+	idleTimeout time.Duration // or 0 for never
+	idleTimer   *time.Timer
 
-	// Settings from peer:
+	mu              sync.Mutex // guards following
+	cond            *sync.Cond // hold mu; broadcast on flow/closed changes
+	flow            flow       // our conn-level flow control quota (cs.flow is per stream)
+	inflow          flow       // peer's conn-level flow control
+	closed          bool
+	wantSettingsAck bool                     // we sent a SETTINGS frame and haven't heard back
+	goAway          *GoAwayFrame             // if non-nil, the GoAwayFrame we received
+	goAwayDebug     string                   // goAway frame's debug data, retained as a string
+	streams         map[uint32]*clientStream // client-initiated
+	nextStreamID    uint32
+	pings           map[[8]byte]chan struct{} // in flight ping data to notification channel
+	bw              *bufio.Writer
+	br              *bufio.Reader
+	fr              *Framer
+	lastActive      time.Time
+	// Settings from peer: (also guarded by mu)
 	maxFrameSize         uint32
 	maxConcurrentStreams uint32
 	initialWindowSize    uint32
-	hbuf                 bytes.Buffer // HPACK encoder writes into this
-	henc                 *hpack.Encoder
-	freeBuf              [][]byte
+
+	hbuf    bytes.Buffer // HPACK encoder writes into this
+	henc    *hpack.Encoder
+	freeBuf [][]byte
 
 	wmu  sync.Mutex // held while writing; acquire AFTER mu if holding both
 	werr error      // first write error that has occurred
@@ -183,6 +191,7 @@ type clientStream struct {
 	ID            uint32
 	resc          chan resAndError
 	bufPipe       pipe // buffered pipe with the flow-controlled response payload
+	startedWrite  bool // started request body write; guarded by cc.mu
 	requestedGzip bool
 	on100         func() // optional code to run if get a 100 continue response
 
@@ -191,6 +200,7 @@ type clientStream struct {
 	bytesRemain int64 // -1 means unknown; owned by transportResponseBody.Read
 	readErr     error // sticky read error; owned by transportResponseBody.Read
 	stopReqBody error // if non-nil, stop writing req body; guarded by cc.mu
+	didReset    bool  // whether we sent a RST_STREAM to the server; guarded by cc.mu
 
 	peerReset chan struct{} // closed on peer reset
 	resetErr  error         // populated before peerReset is closed
@@ -218,15 +228,26 @@ func (cs *clientStream) awaitRequestCancel(req *http.Request) {
 	}
 	select {
 	case <-req.Cancel:
+		cs.cancelStream()
 		cs.bufPipe.CloseWithError(errRequestCanceled)
-		cs.cc.writeStreamReset(cs.ID, ErrCodeCancel, nil)
 	case <-ctx.Done():
+		cs.cancelStream()
 		cs.bufPipe.CloseWithError(ctx.Err())
-		cs.cc.writeStreamReset(cs.ID, ErrCodeCancel, nil)
 	case <-cs.done:
 	}
 }
 
+func (cs *clientStream) cancelStream() {
+	cs.cc.mu.Lock()
+	didReset := cs.didReset
+	cs.didReset = true
+	cs.cc.mu.Unlock()
+
+	if !didReset {
+		cs.cc.writeStreamReset(cs.ID, ErrCodeCancel, nil)
+	}
+}
+
 // checkResetOrDone reports any error sent in a RST_STREAM frame by the
 // server, or errStreamClosed if the stream is complete.
 func (cs *clientStream) checkResetOrDone() error {
@@ -283,14 +304,22 @@ func (t *Transport) RoundTrip(req *http.Request) (*http.Response, error) {
 // authorityAddr returns a given authority (a host/IP, or host:port / ip:port)
 // and returns a host:port. The port 443 is added if needed.
 func authorityAddr(scheme string, authority string) (addr string) {
-	if _, _, err := net.SplitHostPort(authority); err == nil {
-		return authority
+	host, port, err := net.SplitHostPort(authority)
+	if err != nil { // authority didn't have a port
+		port = "443"
+		if scheme == "http" {
+			port = "80"
+		}
+		host = authority
 	}
-	port := "443"
-	if scheme == "http" {
-		port = "80"
+	if a, err := idna.ToASCII(host); err == nil {
+		host = a
 	}
-	return net.JoinHostPort(authority, port)
+	// IPv6 address literal, without a port:
+	if strings.HasPrefix(host, "[") && strings.HasSuffix(host, "]") {
+		return host + ":" + port
+	}
+	return net.JoinHostPort(host, port)
 }
 
 // RoundTripOpt is like RoundTrip, but takes options.
@@ -308,8 +337,10 @@ func (t *Transport) RoundTripOpt(req *http.Request, opt RoundTripOpt) (*http.Res
 		}
 		traceGotConn(req, cc)
 		res, err := cc.RoundTrip(req)
-		if shouldRetryRequest(req, err) {
-			continue
+		if err != nil {
+			if req, err = shouldRetryRequest(req, err); err == nil {
+				continue
+			}
 		}
 		if err != nil {
 			t.vlogf("RoundTrip failure: %v", err)
@@ -331,12 +362,41 @@ func (t *Transport) CloseIdleConnections() {
 var (
 	errClientConnClosed   = errors.New("http2: client conn is closed")
 	errClientConnUnusable = errors.New("http2: client conn not usable")
+
+	errClientConnGotGoAway                 = errors.New("http2: Transport received Server's graceful shutdown GOAWAY")
+	errClientConnGotGoAwayAfterSomeReqBody = errors.New("http2: Transport received Server's graceful shutdown GOAWAY; some request body already written")
 )
 
-func shouldRetryRequest(req *http.Request, err error) bool {
-	// TODO: retry GET requests (no bodies) more aggressively, if shutdown
-	// before response.
-	return err == errClientConnUnusable
+// shouldRetryRequest is called by RoundTrip when a request fails to get
+// response headers. It is always called with a non-nil error.
+// It returns either a request to retry (either the same request, or a
+// modified clone), or an error if the request can't be replayed.
+func shouldRetryRequest(req *http.Request, err error) (*http.Request, error) {
+	switch err {
+	default:
+		return nil, err
+	case errClientConnUnusable, errClientConnGotGoAway:
+		return req, nil
+	case errClientConnGotGoAwayAfterSomeReqBody:
+		// If the Body is nil (or http.NoBody), it's safe to reuse
+		// this request and its Body.
+		if req.Body == nil || reqBodyIsNoBody(req.Body) {
+			return req, nil
+		}
+		// Otherwise we depend on the Request having its GetBody
+		// func defined.
+		getBody := reqGetBody(req) // Go 1.8: getBody = req.GetBody
+		if getBody == nil {
+			return nil, errors.New("http2: Transport: peer server initiated graceful shutdown after some of Request.Body was written; define Request.GetBody to avoid this error")
+		}
+		body, err := getBody()
+		if err != nil {
+			return nil, err
+		}
+		newReq := *req
+		newReq.Body = body
+		return &newReq, nil
+	}
 }
 
 func (t *Transport) dialClientConn(addr string, singleUse bool) (*ClientConn, error) {
@@ -354,7 +414,7 @@ func (t *Transport) dialClientConn(addr string, singleUse bool) (*ClientConn, er
 func (t *Transport) newTLSConfig(host string) *tls.Config {
 	cfg := new(tls.Config)
 	if t.TLSClientConfig != nil {
-		*cfg = *t.TLSClientConfig
+		*cfg = *cloneTLSConfig(t.TLSClientConfig)
 	}
 	if !strSliceContains(cfg.NextProtos, NextProtoTLS) {
 		cfg.NextProtos = append([]string{NextProtoTLS}, cfg.NextProtos...)
@@ -413,14 +473,6 @@ func (t *Transport) NewClientConn(c net.Conn) (*ClientConn, error) {
 }
 
 func (t *Transport) newClientConn(c net.Conn, singleUse bool) (*ClientConn, error) {
-	if VerboseLogs {
-		t.vlogf("http2: Transport creating client conn to %v", c.RemoteAddr())
-	}
-	if _, err := c.Write(clientPreface); err != nil {
-		t.vlogf("client preface write error: %v", err)
-		return nil, err
-	}
-
 	cc := &ClientConn{
 		t:                    t,
 		tconn:                c,
@@ -431,7 +483,17 @@ func (t *Transport) newClientConn(c net.Conn, singleUse bool) (*ClientConn, erro
 		maxConcurrentStreams: 1000,     // "infinite", per spec. 1000 seems good enough.
 		streams:              make(map[uint32]*clientStream),
 		singleUse:            singleUse,
+		wantSettingsAck:      true,
+		pings:                make(map[[8]byte]chan struct{}),
 	}
+	if d := t.idleConnTimeout(); d != 0 {
+		cc.idleTimeout = d
+		cc.idleTimer = time.AfterFunc(d, cc.onIdleTimeout)
+	}
+	if VerboseLogs {
+		t.vlogf("http2: Transport creating client conn %p to %v", cc, c.RemoteAddr())
+	}
+
 	cc.cond = sync.NewCond(&cc.mu)
 	cc.flow.add(int32(initialWindowSize))
 
@@ -459,6 +521,8 @@ func (t *Transport) newClientConn(c net.Conn, singleUse bool) (*ClientConn, erro
 	if max := t.maxHeaderListSize(); max != 0 {
 		initialSettings = append(initialSettings, Setting{ID: SettingMaxHeaderListSize, Val: max})
 	}
+
+	cc.bw.Write(clientPreface)
 	cc.fr.WriteSettings(initialSettings...)
 	cc.fr.WriteWindowUpdate(0, transportDefaultConnFlow)
 	cc.inflow.add(transportDefaultConnFlow + initialWindowSize)
@@ -467,33 +531,6 @@ func (t *Transport) newClientConn(c net.Conn, singleUse bool) (*ClientConn, erro
 		return nil, cc.werr
 	}
 
-	// Read the obligatory SETTINGS frame
-	f, err := cc.fr.ReadFrame()
-	if err != nil {
-		return nil, err
-	}
-	sf, ok := f.(*SettingsFrame)
-	if !ok {
-		return nil, fmt.Errorf("expected settings frame, got: %T", f)
-	}
-	cc.fr.WriteSettingsAck()
-	cc.bw.Flush()
-
-	sf.ForeachSetting(func(s Setting) error {
-		switch s.ID {
-		case SettingMaxFrameSize:
-			cc.maxFrameSize = s.Val
-		case SettingMaxConcurrentStreams:
-			cc.maxConcurrentStreams = s.Val
-		case SettingInitialWindowSize:
-			cc.initialWindowSize = s.Val
-		default:
-			// TODO(bradfitz): handle more; at least SETTINGS_HEADER_TABLE_SIZE?
-			t.vlogf("Unhandled Setting: %v", s)
-		}
-		return nil
-	})
-
 	go cc.readLoop()
 	return cc, nil
 }
@@ -512,6 +549,15 @@ func (cc *ClientConn) setGoAway(f *GoAwayFrame) {
 	if old != nil && old.ErrCode != ErrCodeNo {
 		cc.goAway.ErrCode = old.ErrCode
 	}
+	last := f.LastStreamID
+	for streamID, cs := range cc.streams {
+		if streamID > last {
+			select {
+			case cs.resc <- resAndError{err: errClientConnGotGoAway}:
+			default:
+			}
+		}
+	}
 }
 
 func (cc *ClientConn) CanTakeNewRequest() bool {
@@ -526,7 +572,17 @@ func (cc *ClientConn) canTakeNewRequestLocked() bool {
 	}
 	return cc.goAway == nil && !cc.closed &&
 		int64(len(cc.streams)+1) < int64(cc.maxConcurrentStreams) &&
-		cc.nextStreamID < 2147483647
+		cc.nextStreamID < math.MaxInt32
+}
+
+// onIdleTimeout is called from a time.AfterFunc goroutine. It will
+// only be called when we're idle, but because we're coming from a new
+// goroutine, there could be a new request coming in at the same time,
+// so this simply calls the synchronized closeIfIdle to shut down this
+// connection. The timer could just call closeIfIdle, but this is more
+// clear.
+func (cc *ClientConn) onIdleTimeout() {
+	cc.closeIfIdle()
 }
 
 func (cc *ClientConn) closeIfIdle() {
@@ -536,9 +592,13 @@ func (cc *ClientConn) closeIfIdle() {
 		return
 	}
 	cc.closed = true
+	nextID := cc.nextStreamID
 	// TODO: do clients send GOAWAY too? maybe? Just Close:
 	cc.mu.Unlock()
 
+	if VerboseLogs {
+		cc.vlogf("http2: Transport closing idle conn %p (forSingleUse=%v, maxStream=%v)", cc, cc.singleUse, nextID-2)
+	}
 	cc.tconn.Close()
 }
 
@@ -598,8 +658,6 @@ func commaSeparatedTrailers(req *http.Request) (string, error) {
 	}
 	if len(keys) > 0 {
 		sort.Strings(keys)
-		// TODO: could do better allocation-wise here, but trailers are rare,
-		// so being lazy for now.
 		return strings.Join(keys, ","), nil
 	}
 	return "", nil
@@ -621,48 +679,37 @@ func (cc *ClientConn) responseHeaderTimeout() time.Duration {
 // Certain headers are special-cased as okay but not transmitted later.
 func checkConnHeaders(req *http.Request) error {
 	if v := req.Header.Get("Upgrade"); v != "" {
-		return errors.New("http2: invalid Upgrade request header")
+		return fmt.Errorf("http2: invalid Upgrade request header: %q", req.Header["Upgrade"])
 	}
-	if v := req.Header.Get("Transfer-Encoding"); (v != "" && v != "chunked") || len(req.Header["Transfer-Encoding"]) > 1 {
-		return errors.New("http2: invalid Transfer-Encoding request header")
+	if vv := req.Header["Transfer-Encoding"]; len(vv) > 0 && (len(vv) > 1 || vv[0] != "" && vv[0] != "chunked") {
+		return fmt.Errorf("http2: invalid Transfer-Encoding request header: %q", vv)
 	}
-	if v := req.Header.Get("Connection"); (v != "" && v != "close" && v != "keep-alive") || len(req.Header["Connection"]) > 1 {
-		return errors.New("http2: invalid Connection request header")
+	if vv := req.Header["Connection"]; len(vv) > 0 && (len(vv) > 1 || vv[0] != "" && vv[0] != "close" && vv[0] != "keep-alive") {
+		return fmt.Errorf("http2: invalid Connection request header: %q", vv)
 	}
 	return nil
 }
 
-func bodyAndLength(req *http.Request) (body io.Reader, contentLen int64) {
-	body = req.Body
-	if body == nil {
-		return nil, 0
+// actualContentLength returns a sanitized version of
+// req.ContentLength, where 0 actually means zero (not unknown) and -1
+// means unknown.
+func actualContentLength(req *http.Request) int64 {
+	if req.Body == nil {
+		return 0
 	}
 	if req.ContentLength != 0 {
-		return req.Body, req.ContentLength
+		return req.ContentLength
 	}
-
-	// We have a body but a zero content length. Test to see if
-	// it's actually zero or just unset.
-	var buf [1]byte
-	n, rerr := io.ReadFull(body, buf[:])
-	if rerr != nil && rerr != io.EOF {
-		return errorReader{rerr}, -1
-	}
-	if n == 1 {
-		// Oh, guess there is data in this Body Reader after all.
-		// The ContentLength field just wasn't set.
-		// Stich the Body back together again, re-attaching our
-		// consumed byte.
-		return io.MultiReader(bytes.NewReader(buf[:]), body), -1
-	}
-	// Body is actually zero bytes.
-	return nil, 0
+	return -1
 }
 
 func (cc *ClientConn) RoundTrip(req *http.Request) (*http.Response, error) {
 	if err := checkConnHeaders(req); err != nil {
 		return nil, err
 	}
+	if cc.idleTimer != nil {
+		cc.idleTimer.Stop()
+	}
 
 	trailers, err := commaSeparatedTrailers(req)
 	if err != nil {
@@ -670,9 +717,6 @@ func (cc *ClientConn) RoundTrip(req *http.Request) (*http.Response, error) {
 	}
 	hasTrailers := trailers != ""
 
-	body, contentLen := bodyAndLength(req)
-	hasBody := body != nil
-
 	cc.mu.Lock()
 	cc.lastActive = time.Now()
 	if cc.closed || !cc.canTakeNewRequestLocked() {
@@ -680,6 +724,10 @@ func (cc *ClientConn) RoundTrip(req *http.Request) (*http.Response, error) {
 		return nil, errClientConnUnusable
 	}
 
+	body := req.Body
+	hasBody := body != nil
+	contentLen := actualContentLength(req)
+
 	// TODO(bradfitz): this is a copy of the logic in net/http. Unify somewhere?
 	var requestedGzip bool
 	if !cc.t.disableCompression() &&
@@ -761,13 +809,20 @@ func (cc *ClientConn) RoundTrip(req *http.Request) (*http.Response, error) {
 			// 2xx, however, then assume the server DOES potentially
 			// want our body (e.g. full-duplex streaming:
 			// golang.org/issue/13444). If it turns out the server
-			// doesn't, they'll RST_STREAM us soon enough.  This is a
-			// heuristic to avoid adding knobs to Transport.  Hopefully
+			// doesn't, they'll RST_STREAM us soon enough. This is a
+			// heuristic to avoid adding knobs to Transport. Hopefully
 			// we can keep it.
 			bodyWriter.cancel()
 			cs.abortRequestBodyWrite(errStopReqBodyWrite)
 		}
 		if re.err != nil {
+			if re.err == errClientConnGotGoAway {
+				cc.mu.Lock()
+				if cs.startedWrite {
+					re.err = errClientConnGotGoAwayAfterSomeReqBody
+				}
+				cc.mu.Unlock()
+			}
 			cc.forgetStreamID(cs.ID)
 			return nil, re.err
 		}
@@ -923,10 +978,11 @@ func (cs *clientStream) writeRequestBody(body io.Reader, bodyCloser io.Closer) (
 			err = cc.fr.WriteData(cs.ID, sentEnd, data)
 			if err == nil {
 				// TODO(bradfitz): this flush is for latency, not bandwidth.
-				// Most requests won't need this. Make this opt-in or opt-out?
-				// Use some heuristic on the body type? Nagel-like timers?
-				// Based on 'n'? Only last chunk of this for loop, unless flow control
-				// tokens are low? For now, always:
+				// Most requests won't need this. Make this opt-in or
+				// opt-out?  Use some heuristic on the body type? Nagel-like
+				// timers?  Based on 'n'? Only last chunk of this for loop,
+				// unless flow control tokens are low? For now, always.
+				// If we change this, see comment below.
 				err = cc.bw.Flush()
 			}
 			cc.wmu.Unlock()
@@ -936,28 +992,33 @@ func (cs *clientStream) writeRequestBody(body io.Reader, bodyCloser io.Closer) (
 		}
 	}
 
-	cc.wmu.Lock()
-	if !sentEnd {
-		var trls []byte
-		if hasTrailers {
-			cc.mu.Lock()
-			trls = cc.encodeTrailers(req)
-			cc.mu.Unlock()
-		}
+	if sentEnd {
+		// Already sent END_STREAM (which implies we have no
+		// trailers) and flushed, because currently all
+		// WriteData frames above get a flush. So we're done.
+		return nil
+	}
 
-		// Avoid forgetting to send an END_STREAM if the encoded
-		// trailers are 0 bytes. Both results produce and END_STREAM.
-		if len(trls) > 0 {
-			err = cc.writeHeaders(cs.ID, true, trls)
-		} else {
-			err = cc.fr.WriteData(cs.ID, true, nil)
-		}
+	var trls []byte
+	if hasTrailers {
+		cc.mu.Lock()
+		defer cc.mu.Unlock()
+		trls = cc.encodeTrailers(req)
+	}
+
+	cc.wmu.Lock()
+	defer cc.wmu.Unlock()
+
+	// Two ways to send END_STREAM: either with trailers, or
+	// with an empty DATA frame.
+	if len(trls) > 0 {
+		err = cc.writeHeaders(cs.ID, true, trls)
+	} else {
+		err = cc.fr.WriteData(cs.ID, true, nil)
 	}
 	if ferr := cc.bw.Flush(); ferr != nil && err == nil {
 		err = ferr
 	}
-	cc.wmu.Unlock()
-
 	return err
 }
 
@@ -1010,6 +1071,26 @@ func (cc *ClientConn) encodeHeaders(req *http.Request, addGzipHeader bool, trail
 	if host == "" {
 		host = req.URL.Host
 	}
+	host, err := httplex.PunycodeHostPort(host)
+	if err != nil {
+		return nil, err
+	}
+
+	var path string
+	if req.Method != "CONNECT" {
+		path = req.URL.RequestURI()
+		if !validPseudoPath(path) {
+			orig := path
+			path = strings.TrimPrefix(path, req.URL.Scheme+"://"+host)
+			if !validPseudoPath(path) {
+				if req.URL.Opaque != "" {
+					return nil, fmt.Errorf("invalid request :path %q from URL.Opaque = %q", orig, req.URL.Opaque)
+				} else {
+					return nil, fmt.Errorf("invalid request :path %q", orig)
+				}
+			}
+		}
+	}
 
 	// Check for any invalid headers and return an error before we
 	// potentially pollute our hpack state. (We want to be able to
@@ -1033,8 +1114,8 @@ func (cc *ClientConn) encodeHeaders(req *http.Request, addGzipHeader bool, trail
 	cc.writeHeader(":authority", host)
 	cc.writeHeader(":method", req.Method)
 	if req.Method != "CONNECT" {
-		cc.writeHeader(":path", req.URL.RequestURI())
-		cc.writeHeader(":scheme", "https")
+		cc.writeHeader(":path", path)
+		cc.writeHeader(":scheme", req.URL.Scheme)
 	}
 	if trailers != "" {
 		cc.writeHeader("trailer", trailers)
@@ -1161,6 +1242,9 @@ func (cc *ClientConn) streamByID(id uint32, andRemove bool) *clientStream {
 	if andRemove && cs != nil && !cc.closed {
 		cc.lastActive = time.Now()
 		delete(cc.streams, id)
+		if len(cc.streams) == 0 && cc.idleTimer != nil {
+			cc.idleTimer.Reset(cc.idleTimeout)
+		}
 		close(cs.done)
 		cc.cond.Broadcast() // wake up checkResetOrDone via clientStream.awaitFlowControl
 	}
@@ -1203,27 +1287,37 @@ func (e GoAwayError) Error() string {
 		e.LastStreamID, e.ErrCode, e.DebugData)
 }
 
+func isEOFOrNetReadError(err error) bool {
+	if err == io.EOF {
+		return true
+	}
+	ne, ok := err.(*net.OpError)
+	return ok && ne.Op == "read"
+}
+
 func (rl *clientConnReadLoop) cleanup() {
 	cc := rl.cc
 	defer cc.tconn.Close()
 	defer cc.t.connPool().MarkDead(cc)
 	defer close(cc.readerDone)
 
+	if cc.idleTimer != nil {
+		cc.idleTimer.Stop()
+	}
+
 	// Close any response bodies if the server closes prematurely.
 	// TODO: also do this if we've written the headers but not
 	// gotten a response yet.
 	err := cc.readerErr
 	cc.mu.Lock()
-	if err == io.EOF {
-		if cc.goAway != nil {
-			err = GoAwayError{
-				LastStreamID: cc.goAway.LastStreamID,
-				ErrCode:      cc.goAway.ErrCode,
-				DebugData:    cc.goAwayDebug,
-			}
-		} else {
-			err = io.ErrUnexpectedEOF
+	if cc.goAway != nil && isEOFOrNetReadError(err) {
+		err = GoAwayError{
+			LastStreamID: cc.goAway.LastStreamID,
+			ErrCode:      cc.goAway.ErrCode,
+			DebugData:    cc.goAwayDebug,
 		}
+	} else if err == io.EOF {
+		err = io.ErrUnexpectedEOF
 	}
 	for _, cs := range rl.activeRes {
 		cs.bufPipe.CloseWithError(err)
@@ -1243,15 +1337,20 @@ func (rl *clientConnReadLoop) cleanup() {
 func (rl *clientConnReadLoop) run() error {
 	cc := rl.cc
 	rl.closeWhenIdle = cc.t.disableKeepAlives() || cc.singleUse
-	gotReply := false // ever saw a reply
+	gotReply := false // ever saw a HEADERS reply
+	gotSettings := false
 	for {
 		f, err := cc.fr.ReadFrame()
 		if err != nil {
-			cc.vlogf("Transport readFrame error: (%T) %v", err, err)
+			cc.vlogf("http2: Transport readFrame error on conn %p: (%T) %v", cc, err, err)
 		}
 		if se, ok := err.(StreamError); ok {
 			if cs := cc.streamByID(se.StreamID, true /*ended; remove it*/); cs != nil {
-				rl.endStreamError(cs, cc.fr.errDetail)
+				cs.cc.writeStreamReset(cs.ID, se.Code, err)
+				if se.Cause == nil {
+					se.Cause = cc.fr.errDetail
+				}
+				rl.endStreamError(cs, se)
 			}
 			continue
 		} else if err != nil {
@@ -1260,6 +1359,13 @@ func (rl *clientConnReadLoop) run() error {
 		if VerboseLogs {
 			cc.vlogf("http2: Transport received %s", summarizeFrame(f))
 		}
+		if !gotSettings {
+			if _, ok := f.(*SettingsFrame); !ok {
+				cc.logf("protocol error: received %T before a SETTINGS frame", f)
+				return ConnectionError(ErrCodeProtocol)
+			}
+			gotSettings = true
+		}
 		maybeIdle := false // whether frame might transition us to idle
 
 		switch f := f.(type) {
@@ -1288,6 +1394,9 @@ func (rl *clientConnReadLoop) run() error {
 			cc.logf("Transport: unhandled response frame type %T", f)
 		}
 		if err != nil {
+			if VerboseLogs {
+				cc.vlogf("http2: Transport conn %p received error from processing frame %v: %v", cc, summarizeFrame(f), err)
+			}
 			return err
 		}
 		if rl.closeWhenIdle && gotReply && maybeIdle && len(rl.activeRes) == 0 {
@@ -1419,8 +1528,7 @@ func (rl *clientConnReadLoop) handleResponse(cs *clientStream, f *MetaHeadersFra
 		return res, nil
 	}
 
-	buf := new(bytes.Buffer) // TODO(bradfitz): recycle this garbage
-	cs.bufPipe = pipe{b: buf}
+	cs.bufPipe = pipe{b: &dataBuffer{expected: res.ContentLength}}
 	cs.bytesRemain = res.ContentLength
 	res.Body = transportResponseBody{cs}
 	go cs.awaitRequestCancel(cs.req)
@@ -1581,16 +1689,20 @@ func (rl *clientConnReadLoop) processData(f *DataFrame) error {
 		// by the peer? Tough without accumulating too much state.
 
 		// But at least return their flow control:
-		if len(data) > 0 {
+		if f.Length > 0 {
+			cc.mu.Lock()
+			cc.inflow.add(int32(f.Length))
+			cc.mu.Unlock()
+
 			cc.wmu.Lock()
-			cc.fr.WriteWindowUpdate(0, uint32(len(data)))
+			cc.fr.WriteWindowUpdate(0, uint32(f.Length))
 			cc.bw.Flush()
 			cc.wmu.Unlock()
 		}
 		return nil
 	}
-	if len(data) > 0 {
-		if cs.bufPipe.b == nil {
+	if f.Length > 0 {
+		if len(data) > 0 && cs.bufPipe.b == nil {
 			// Data frame after it's already closed?
 			cc.logf("http2: Transport received DATA frame for closed stream; closing connection")
 			return ConnectionError(ErrCodeProtocol)
@@ -1598,17 +1710,31 @@ func (rl *clientConnReadLoop) processData(f *DataFrame) error {
 
 		// Check connection-level flow control.
 		cc.mu.Lock()
-		if cs.inflow.available() >= int32(len(data)) {
-			cs.inflow.take(int32(len(data)))
+		if cs.inflow.available() >= int32(f.Length) {
+			cs.inflow.take(int32(f.Length))
 		} else {
 			cc.mu.Unlock()
 			return ConnectionError(ErrCodeFlowControl)
 		}
+		// Return any padded flow control now, since we won't
+		// refund it later on body reads.
+		if pad := int32(f.Length) - int32(len(data)); pad > 0 {
+			cs.inflow.add(pad)
+			cc.inflow.add(pad)
+			cc.wmu.Lock()
+			cc.fr.WriteWindowUpdate(0, uint32(pad))
+			cc.fr.WriteWindowUpdate(cs.ID, uint32(pad))
+			cc.bw.Flush()
+			cc.wmu.Unlock()
+		}
+		didReset := cs.didReset
 		cc.mu.Unlock()
 
-		if _, err := cs.bufPipe.Write(data); err != nil {
-			rl.endStreamError(cs, err)
-			return err
+		if len(data) > 0 && !didReset {
+			if _, err := cs.bufPipe.Write(data); err != nil {
+				rl.endStreamError(cs, err)
+				return err
+			}
 		}
 	}
 
@@ -1637,6 +1763,11 @@ func (rl *clientConnReadLoop) endStreamError(cs *clientStream, err error) {
 	if isConnectionCloseRequest(cs.req) {
 		rl.closeWhenIdle = true
 	}
+
+	select {
+	case cs.resc <- resAndError{err: err}:
+	default:
+	}
 }
 
 func (cs *clientStream) copyTrailers() {
@@ -1664,18 +1795,39 @@ func (rl *clientConnReadLoop) processSettings(f *SettingsFrame) error {
 	cc := rl.cc
 	cc.mu.Lock()
 	defer cc.mu.Unlock()
-	return f.ForeachSetting(func(s Setting) error {
+
+	if f.IsAck() {
+		if cc.wantSettingsAck {
+			cc.wantSettingsAck = false
+			return nil
+		}
+		return ConnectionError(ErrCodeProtocol)
+	}
+
+	err := f.ForeachSetting(func(s Setting) error {
 		switch s.ID {
 		case SettingMaxFrameSize:
 			cc.maxFrameSize = s.Val
 		case SettingMaxConcurrentStreams:
 			cc.maxConcurrentStreams = s.Val
 		case SettingInitialWindowSize:
-			// TODO: error if this is too large.
+			// Values above the maximum flow-control
+			// window size of 2^31-1 MUST be treated as a
+			// connection error (Section 5.4.1) of type
+			// FLOW_CONTROL_ERROR.
+			if s.Val > math.MaxInt32 {
+				return ConnectionError(ErrCodeFlowControl)
+			}
 
-			// TODO: adjust flow control of still-open
+			// Adjust flow control of currently-open
 			// frames by the difference of the old initial
 			// window size and this one.
+			delta := int32(s.Val) - int32(cc.initialWindowSize)
+			for _, cs := range cc.streams {
+				cs.flow.add(delta)
+			}
+			cc.cond.Broadcast()
+
 			cc.initialWindowSize = s.Val
 		default:
 			// TODO(bradfitz): handle more settings? SETTINGS_HEADER_TABLE_SIZE probably.
@@ -1683,6 +1835,16 @@ func (rl *clientConnReadLoop) processSettings(f *SettingsFrame) error {
 		}
 		return nil
 	})
+	if err != nil {
+		return err
+	}
+
+	cc.wmu.Lock()
+	defer cc.wmu.Unlock()
+
+	cc.fr.WriteSettingsAck()
+	cc.bw.Flush()
+	return cc.werr
 }
 
 func (rl *clientConnReadLoop) processWindowUpdate(f *WindowUpdateFrame) error {
@@ -1719,7 +1881,7 @@ func (rl *clientConnReadLoop) processResetStream(f *RSTStreamFrame) error {
 		// which closes this, so there
 		// isn't a race.
 	default:
-		err := StreamError{cs.ID, f.ErrCode}
+		err := streamError(cs.ID, f.ErrCode)
 		cs.resetErr = err
 		close(cs.peerReset)
 		cs.bufPipe.CloseWithError(err)
@@ -1729,10 +1891,56 @@ func (rl *clientConnReadLoop) processResetStream(f *RSTStreamFrame) error {
 	return nil
 }
 
+// Ping sends a PING frame to the server and waits for the ack.
+// Public implementation is in go17.go and not_go17.go
+func (cc *ClientConn) ping(ctx contextContext) error {
+	c := make(chan struct{})
+	// Generate a random payload
+	var p [8]byte
+	for {
+		if _, err := rand.Read(p[:]); err != nil {
+			return err
+		}
+		cc.mu.Lock()
+		// check for dup before insert
+		if _, found := cc.pings[p]; !found {
+			cc.pings[p] = c
+			cc.mu.Unlock()
+			break
+		}
+		cc.mu.Unlock()
+	}
+	cc.wmu.Lock()
+	if err := cc.fr.WritePing(false, p); err != nil {
+		cc.wmu.Unlock()
+		return err
+	}
+	if err := cc.bw.Flush(); err != nil {
+		cc.wmu.Unlock()
+		return err
+	}
+	cc.wmu.Unlock()
+	select {
+	case <-c:
+		return nil
+	case <-ctx.Done():
+		return ctx.Err()
+	case <-cc.readerDone:
+		// connection closed
+		return cc.readerErr
+	}
+}
+
 func (rl *clientConnReadLoop) processPing(f *PingFrame) error {
 	if f.IsAck() {
-		// 6.7 PING: " An endpoint MUST NOT respond to PING frames
-		// containing this flag."
+		cc := rl.cc
+		cc.mu.Lock()
+		defer cc.mu.Unlock()
+		// If ack, notify listener if any
+		if c, ok := cc.pings[f.Data]; ok {
+			close(c)
+			delete(cc.pings, f.Data)
+		}
 		return nil
 	}
 	cc := rl.cc
@@ -1854,6 +2062,9 @@ func (t *Transport) getBodyWriterState(cs *clientStream, body io.Reader) (s body
 	resc := make(chan error, 1)
 	s.resc = resc
 	s.fn = func() {
+		cs.cc.mu.Lock()
+		cs.startedWrite = true
+		cs.cc.mu.Unlock()
 		resc <- cs.writeRequestBody(body, cs.req.Body)
 	}
 	s.delay = t.expectContinueTimeout()

vendor/golang.org/x/net/http2/write.go

@@ -9,6 +9,7 @@ import (
 	"fmt"
 	"log"
 	"net/http"
+	"net/url"
 	"time"
 
 	"golang.org/x/net/http2/hpack"
@@ -18,6 +19,11 @@ import (
 // writeFramer is implemented by any type that is used to write frames.
 type writeFramer interface {
 	writeFrame(writeContext) error
+
+	// staysWithinBuffer reports whether this writer promises that
+	// it will only write less than or equal to size bytes, and it
+	// won't Flush the write context.
+	staysWithinBuffer(size int) bool
 }
 
 // writeContext is the interface needed by the various frame writer
@@ -39,9 +45,10 @@ type writeContext interface {
 	HeaderEncoder() (*hpack.Encoder, *bytes.Buffer)
 }
 
-// endsStream reports whether the given frame writer w will locally
-// close the stream.
-func endsStream(w writeFramer) bool {
+// writeEndsStream reports whether w writes a frame that will transition
+// the stream to a half-closed local state. This returns false for RST_STREAM,
+// which closes the entire stream (not just the local half).
+func writeEndsStream(w writeFramer) bool {
 	switch v := w.(type) {
 	case *writeData:
 		return v.endStream
@@ -51,7 +58,7 @@ func endsStream(w writeFramer) bool {
 		// This can only happen if the caller reuses w after it's
 		// been intentionally nil'ed out to prevent use. Keep this
 		// here to catch future refactoring breaking it.
-		panic("endsStream called on nil writeFramer")
+		panic("writeEndsStream called on nil writeFramer")
 	}
 	return false
 }
@@ -62,8 +69,16 @@ func (flushFrameWriter) writeFrame(ctx writeContext) error {
 	return ctx.Flush()
 }
 
+func (flushFrameWriter) staysWithinBuffer(max int) bool { return false }
+
 type writeSettings []Setting
 
+func (s writeSettings) staysWithinBuffer(max int) bool {
+	const settingSize = 6 // uint16 + uint32
+	return frameHeaderLen+settingSize*len(s) <= max
+
+}
+
 func (s writeSettings) writeFrame(ctx writeContext) error {
 	return ctx.Framer().WriteSettings([]Setting(s)...)
 }
@@ -83,6 +98,8 @@ func (p *writeGoAway) writeFrame(ctx writeContext) error {
 	return err
 }
 
+func (*writeGoAway) staysWithinBuffer(max int) bool { return false } // flushes
+
 type writeData struct {
 	streamID  uint32
 	p         []byte
@@ -97,6 +114,10 @@ func (w *writeData) writeFrame(ctx writeContext) error {
 	return ctx.Framer().WriteData(w.streamID, w.endStream, w.p)
 }
 
+func (w *writeData) staysWithinBuffer(max int) bool {
+	return frameHeaderLen+len(w.p) <= max
+}
+
 // handlerPanicRST is the message sent from handler goroutines when
 // the handler panics.
 type handlerPanicRST struct {
@@ -107,22 +128,57 @@ func (hp handlerPanicRST) writeFrame(ctx writeContext) error {
 	return ctx.Framer().WriteRSTStream(hp.StreamID, ErrCodeInternal)
 }
 
+func (hp handlerPanicRST) staysWithinBuffer(max int) bool { return frameHeaderLen+4 <= max }
+
 func (se StreamError) writeFrame(ctx writeContext) error {
 	return ctx.Framer().WriteRSTStream(se.StreamID, se.Code)
 }
 
+func (se StreamError) staysWithinBuffer(max int) bool { return frameHeaderLen+4 <= max }
+
 type writePingAck struct{ pf *PingFrame }
 
 func (w writePingAck) writeFrame(ctx writeContext) error {
 	return ctx.Framer().WritePing(true, w.pf.Data)
 }
 
+func (w writePingAck) staysWithinBuffer(max int) bool { return frameHeaderLen+len(w.pf.Data) <= max }
+
 type writeSettingsAck struct{}
 
 func (writeSettingsAck) writeFrame(ctx writeContext) error {
 	return ctx.Framer().WriteSettingsAck()
 }
 
+func (writeSettingsAck) staysWithinBuffer(max int) bool { return frameHeaderLen <= max }
+
+// splitHeaderBlock splits headerBlock into fragments so that each fragment fits
+// in a single frame, then calls fn for each fragment. firstFrag/lastFrag are true
+// for the first/last fragment, respectively.
+func splitHeaderBlock(ctx writeContext, headerBlock []byte, fn func(ctx writeContext, frag []byte, firstFrag, lastFrag bool) error) error {
+	// For now we're lazy and just pick the minimum MAX_FRAME_SIZE
+	// that all peers must support (16KB). Later we could care
+	// more and send larger frames if the peer advertised it, but
+	// there's little point. Most headers are small anyway (so we
+	// generally won't have CONTINUATION frames), and extra frames
+	// only waste 9 bytes anyway.
+	const maxFrameSize = 16384
+
+	first := true
+	for len(headerBlock) > 0 {
+		frag := headerBlock
+		if len(frag) > maxFrameSize {
+			frag = frag[:maxFrameSize]
+		}
+		headerBlock = headerBlock[len(frag):]
+		if err := fn(ctx, frag, first, len(headerBlock) == 0); err != nil {
+			return err
+		}
+		first = false
+	}
+	return nil
+}
+
 // writeResHeaders is a request to write a HEADERS and 0+ CONTINUATION frames
 // for HTTP response headers or trailers from a server handler.
 type writeResHeaders struct {
@@ -144,6 +200,17 @@ func encKV(enc *hpack.Encoder, k, v string) {
 	enc.WriteField(hpack.HeaderField{Name: k, Value: v})
 }
 
+func (w *writeResHeaders) staysWithinBuffer(max int) bool {
+	// TODO: this is a common one. It'd be nice to return true
+	// here and get into the fast path if we could be clever and
+	// calculate the size fast enough, or at least a conservative
+	// uppper bound that usually fires. (Maybe if w.h and
+	// w.trailers are nil, so we don't need to enumerate it.)
+	// Otherwise I'm afraid that just calculating the length to
+	// answer this question would be slower than the ~2µs benefit.
+	return false
+}
+
 func (w *writeResHeaders) writeFrame(ctx writeContext) error {
 	enc, buf := ctx.HeaderEncoder()
 	buf.Reset()
@@ -169,39 +236,69 @@ func (w *writeResHeaders) writeFrame(ctx writeContext) error {
 		panic("unexpected empty hpack")
 	}
 
-	// For now we're lazy and just pick the minimum MAX_FRAME_SIZE
-	// that all peers must support (16KB). Later we could care
-	// more and send larger frames if the peer advertised it, but
-	// there's little point. Most headers are small anyway (so we
-	// generally won't have CONTINUATION frames), and extra frames
-	// only waste 9 bytes anyway.
-	const maxFrameSize = 16384
+	return splitHeaderBlock(ctx, headerBlock, w.writeHeaderBlock)
+}
 
-	first := true
-	for len(headerBlock) > 0 {
-		frag := headerBlock
-		if len(frag) > maxFrameSize {
-			frag = frag[:maxFrameSize]
-		}
-		headerBlock = headerBlock[len(frag):]
-		endHeaders := len(headerBlock) == 0
-		var err error
-		if first {
-			first = false
-			err = ctx.Framer().WriteHeaders(HeadersFrameParam{
-				StreamID:      w.streamID,
-				BlockFragment: frag,
-				EndStream:     w.endStream,
-				EndHeaders:    endHeaders,
-			})
-		} else {
-			err = ctx.Framer().WriteContinuation(w.streamID, endHeaders, frag)
-		}
-		if err != nil {
-			return err
-		}
+func (w *writeResHeaders) writeHeaderBlock(ctx writeContext, frag []byte, firstFrag, lastFrag bool) error {
+	if firstFrag {
+		return ctx.Framer().WriteHeaders(HeadersFrameParam{
+			StreamID:      w.streamID,
+			BlockFragment: frag,
+			EndStream:     w.endStream,
+			EndHeaders:    lastFrag,
+		})
+	} else {
+		return ctx.Framer().WriteContinuation(w.streamID, lastFrag, frag)
+	}
+}
+
+// writePushPromise is a request to write a PUSH_PROMISE and 0+ CONTINUATION frames.
+type writePushPromise struct {
+	streamID uint32   // pusher stream
+	method   string   // for :method
+	url      *url.URL // for :scheme, :authority, :path
+	h        http.Header
+
+	// Creates an ID for a pushed stream. This runs on serveG just before
+	// the frame is written. The returned ID is copied to promisedID.
+	allocatePromisedID func() (uint32, error)
+	promisedID         uint32
+}
+
+func (w *writePushPromise) staysWithinBuffer(max int) bool {
+	// TODO: see writeResHeaders.staysWithinBuffer
+	return false
+}
+
+func (w *writePushPromise) writeFrame(ctx writeContext) error {
+	enc, buf := ctx.HeaderEncoder()
+	buf.Reset()
+
+	encKV(enc, ":method", w.method)
+	encKV(enc, ":scheme", w.url.Scheme)
+	encKV(enc, ":authority", w.url.Host)
+	encKV(enc, ":path", w.url.RequestURI())
+	encodeHeaders(enc, w.h, nil)
+
+	headerBlock := buf.Bytes()
+	if len(headerBlock) == 0 {
+		panic("unexpected empty hpack")
+	}
+
+	return splitHeaderBlock(ctx, headerBlock, w.writeHeaderBlock)
+}
+
+func (w *writePushPromise) writeHeaderBlock(ctx writeContext, frag []byte, firstFrag, lastFrag bool) error {
+	if firstFrag {
+		return ctx.Framer().WritePushPromise(PushPromiseParam{
+			StreamID:      w.streamID,
+			PromiseID:     w.promisedID,
+			BlockFragment: frag,
+			EndHeaders:    lastFrag,
+		})
+	} else {
+		return ctx.Framer().WriteContinuation(w.streamID, lastFrag, frag)
 	}
-	return nil
 }
 
 type write100ContinueHeadersFrame struct {
@@ -220,15 +317,24 @@ func (w write100ContinueHeadersFrame) writeFrame(ctx writeContext) error {
 	})
 }
 
+func (w write100ContinueHeadersFrame) staysWithinBuffer(max int) bool {
+	// Sloppy but conservative:
+	return 9+2*(len(":status")+len("100")) <= max
+}
+
 type writeWindowUpdate struct {
 	streamID uint32 // or 0 for conn-level
 	n        uint32
 }
 
+func (wu writeWindowUpdate) staysWithinBuffer(max int) bool { return frameHeaderLen+4 <= max }
+
 func (wu writeWindowUpdate) writeFrame(ctx writeContext) error {
 	return ctx.Framer().WriteWindowUpdate(wu.streamID, wu.n)
 }
 
+// encodeHeaders encodes an http.Header. If keys is not nil, then (k, h[k])
+// is encoded only only if k is in keys.
 func encodeHeaders(enc *hpack.Encoder, h http.Header, keys []string) {
 	if keys == nil {
 		sorter := sorterPool.Get().(*sorter)

vendor/golang.org/x/net/http2/writesched.go

@@ -6,14 +6,53 @@ package http2
 
 import "fmt"
 
-// frameWriteMsg is a request to write a frame.
-type frameWriteMsg struct {
+// WriteScheduler is the interface implemented by HTTP/2 write schedulers.
+// Methods are never called concurrently.
+type WriteScheduler interface {
+	// OpenStream opens a new stream in the write scheduler.
+	// It is illegal to call this with streamID=0 or with a streamID that is
+	// already open -- the call may panic.
+	OpenStream(streamID uint32, options OpenStreamOptions)
+
+	// CloseStream closes a stream in the write scheduler. Any frames queued on
+	// this stream should be discarded. It is illegal to call this on a stream
+	// that is not open -- the call may panic.
+	CloseStream(streamID uint32)
+
+	// AdjustStream adjusts the priority of the given stream. This may be called
+	// on a stream that has not yet been opened or has been closed. Note that
+	// RFC 7540 allows PRIORITY frames to be sent on streams in any state. See:
+	// https://tools.ietf.org/html/rfc7540#section-5.1
+	AdjustStream(streamID uint32, priority PriorityParam)
+
+	// Push queues a frame in the scheduler. In most cases, this will not be
+	// called with wr.StreamID()!=0 unless that stream is currently open. The one
+	// exception is RST_STREAM frames, which may be sent on idle or closed streams.
+	Push(wr FrameWriteRequest)
+
+	// Pop dequeues the next frame to write. Returns false if no frames can
+	// be written. Frames with a given wr.StreamID() are Pop'd in the same
+	// order they are Push'd.
+	Pop() (wr FrameWriteRequest, ok bool)
+}
+
+// OpenStreamOptions specifies extra options for WriteScheduler.OpenStream.
+type OpenStreamOptions struct {
+	// PusherID is zero if the stream was initiated by the client. Otherwise,
+	// PusherID names the stream that pushed the newly opened stream.
+	PusherID uint32
+}
+
+// FrameWriteRequest is a request to write a frame.
+type FrameWriteRequest struct {
 	// write is the interface value that does the writing, once the
-	// writeScheduler (below) has decided to select this frame
-	// to write. The write functions are all defined in write.go.
+	// WriteScheduler has selected this frame to write. The write
+	// functions are all defined in write.go.
 	write writeFramer
 
-	stream *stream // used for prioritization. nil for non-stream frames.
+	// stream is the stream on which this frame will be written.
+	// nil for non-stream frames like PING and SETTINGS.
+	stream *stream
 
 	// done, if non-nil, must be a buffered channel with space for
 	// 1 message and is sent the return value from write (or an
@@ -21,263 +60,183 @@ type frameWriteMsg struct {
 	done chan error
 }
 
-// for debugging only:
-func (wm frameWriteMsg) String() string {
-	var streamID uint32
-	if wm.stream != nil {
-		streamID = wm.stream.id
-	}
-	var des string
-	if s, ok := wm.write.(fmt.Stringer); ok {
-		des = s.String()
-	} else {
-		des = fmt.Sprintf("%T", wm.write)
-	}
-	return fmt.Sprintf("[frameWriteMsg stream=%d, ch=%v, type: %v]", streamID, wm.done != nil, des)
-}
-
-// writeScheduler tracks pending frames to write, priorities, and decides
-// the next one to use. It is not thread-safe.
-type writeScheduler struct {
-	// zero are frames not associated with a specific stream.
-	// They're sent before any stream-specific freams.
-	zero writeQueue
-
-	// maxFrameSize is the maximum size of a DATA frame
-	// we'll write. Must be non-zero and between 16K-16M.
-	maxFrameSize uint32
-
-	// sq contains the stream-specific queues, keyed by stream ID.
-	// when a stream is idle, it's deleted from the map.
-	sq map[uint32]*writeQueue
-
-	// canSend is a slice of memory that's reused between frame
-	// scheduling decisions to hold the list of writeQueues (from sq)
-	// which have enough flow control data to send. After canSend is
-	// built, the best is selected.
-	canSend []*writeQueue
-
-	// pool of empty queues for reuse.
-	queuePool []*writeQueue
-}
-
-func (ws *writeScheduler) putEmptyQueue(q *writeQueue) {
-	if len(q.s) != 0 {
-		panic("queue must be empty")
-	}
-	ws.queuePool = append(ws.queuePool, q)
-}
-
-func (ws *writeScheduler) getEmptyQueue() *writeQueue {
-	ln := len(ws.queuePool)
-	if ln == 0 {
-		return new(writeQueue)
-	}
-	q := ws.queuePool[ln-1]
-	ws.queuePool = ws.queuePool[:ln-1]
-	return q
-}
-
-func (ws *writeScheduler) empty() bool { return ws.zero.empty() && len(ws.sq) == 0 }
-
-func (ws *writeScheduler) add(wm frameWriteMsg) {
-	st := wm.stream
-	if st == nil {
-		ws.zero.push(wm)
-	} else {
-		ws.streamQueue(st.id).push(wm)
-	}
-}
-
-func (ws *writeScheduler) streamQueue(streamID uint32) *writeQueue {
-	if q, ok := ws.sq[streamID]; ok {
-		return q
-	}
-	if ws.sq == nil {
-		ws.sq = make(map[uint32]*writeQueue)
-	}
-	q := ws.getEmptyQueue()
-	ws.sq[streamID] = q
-	return q
-}
-
-// take returns the most important frame to write and removes it from the scheduler.
-// It is illegal to call this if the scheduler is empty or if there are no connection-level
-// flow control bytes available.
-func (ws *writeScheduler) take() (wm frameWriteMsg, ok bool) {
-	if ws.maxFrameSize == 0 {
-		panic("internal error: ws.maxFrameSize not initialized or invalid")
-	}
-
-	// If there any frames not associated with streams, prefer those first.
-	// These are usually SETTINGS, etc.
-	if !ws.zero.empty() {
-		return ws.zero.shift(), true
-	}
-	if len(ws.sq) == 0 {
-		return
-	}
-
-	// Next, prioritize frames on streams that aren't DATA frames (no cost).
-	for id, q := range ws.sq {
-		if q.firstIsNoCost() {
-			return ws.takeFrom(id, q)
+// StreamID returns the id of the stream this frame will be written to.
+// 0 is used for non-stream frames such as PING and SETTINGS.
+func (wr FrameWriteRequest) StreamID() uint32 {
+	if wr.stream == nil {
+		if se, ok := wr.write.(StreamError); ok {
+			// (*serverConn).resetStream doesn't set
+			// stream because it doesn't necessarily have
+			// one. So special case this type of write
+			// message.
+			return se.StreamID
 		}
-	}
-
-	// Now, all that remains are DATA frames with non-zero bytes to
-	// send. So pick the best one.
-	if len(ws.canSend) != 0 {
-		panic("should be empty")
-	}
-	for _, q := range ws.sq {
-		if n := ws.streamWritableBytes(q); n > 0 {
-			ws.canSend = append(ws.canSend, q)
-		}
-	}
-	if len(ws.canSend) == 0 {
-		return
-	}
-	defer ws.zeroCanSend()
-
-	// TODO: find the best queue
-	q := ws.canSend[0]
-
-	return ws.takeFrom(q.streamID(), q)
-}
-
-// zeroCanSend is defered from take.
-func (ws *writeScheduler) zeroCanSend() {
-	for i := range ws.canSend {
-		ws.canSend[i] = nil
-	}
-	ws.canSend = ws.canSend[:0]
-}
-
-// streamWritableBytes returns the number of DATA bytes we could write
-// from the given queue's stream, if this stream/queue were
-// selected. It is an error to call this if q's head isn't a
-// *writeData.
-func (ws *writeScheduler) streamWritableBytes(q *writeQueue) int32 {
-	wm := q.head()
-	ret := wm.stream.flow.available() // max we can write
-	if ret == 0 {
 		return 0
 	}
-	if int32(ws.maxFrameSize) < ret {
-		ret = int32(ws.maxFrameSize)
-	}
-	if ret == 0 {
-		panic("internal error: ws.maxFrameSize not initialized or invalid")
-	}
-	wd := wm.write.(*writeData)
-	if len(wd.p) < int(ret) {
-		ret = int32(len(wd.p))
-	}
-	return ret
+	return wr.stream.id
 }
 
-func (ws *writeScheduler) takeFrom(id uint32, q *writeQueue) (wm frameWriteMsg, ok bool) {
-	wm = q.head()
-	// If the first item in this queue costs flow control tokens
-	// and we don't have enough, write as much as we can.
-	if wd, ok := wm.write.(*writeData); ok && len(wd.p) > 0 {
-		allowed := wm.stream.flow.available() // max we can write
-		if allowed == 0 {
-			// No quota available. Caller can try the next stream.
-			return frameWriteMsg{}, false
-		}
-		if int32(ws.maxFrameSize) < allowed {
-			allowed = int32(ws.maxFrameSize)
-		}
-		// TODO: further restrict the allowed size, because even if
-		// the peer says it's okay to write 16MB data frames, we might
-		// want to write smaller ones to properly weight competing
-		// streams' priorities.
-
-		if len(wd.p) > int(allowed) {
-			wm.stream.flow.take(allowed)
-			chunk := wd.p[:allowed]
-			wd.p = wd.p[allowed:]
-			// Make up a new write message of a valid size, rather
-			// than shifting one off the queue.
-			return frameWriteMsg{
-				stream: wm.stream,
-				write: &writeData{
-					streamID: wd.streamID,
-					p:        chunk,
-					// even if the original had endStream set, there
-					// arebytes remaining because len(wd.p) > allowed,
-					// so we know endStream is false:
-					endStream: false,
-				},
-				// our caller is blocking on the final DATA frame, not
-				// these intermediates, so no need to wait:
-				done: nil,
-			}, true
-		}
-		wm.stream.flow.take(int32(len(wd.p)))
+// DataSize returns the number of flow control bytes that must be consumed
+// to write this entire frame. This is 0 for non-DATA frames.
+func (wr FrameWriteRequest) DataSize() int {
+	if wd, ok := wr.write.(*writeData); ok {
+		return len(wd.p)
 	}
-
-	q.shift()
-	if q.empty() {
-		ws.putEmptyQueue(q)
-		delete(ws.sq, id)
-	}
-	return wm, true
+	return 0
 }
 
-func (ws *writeScheduler) forgetStream(id uint32) {
-	q, ok := ws.sq[id]
-	if !ok {
+// Consume consumes min(n, available) bytes from this frame, where available
+// is the number of flow control bytes available on the stream. Consume returns
+// 0, 1, or 2 frames, where the integer return value gives the number of frames
+// returned.
+//
+// If flow control prevents consuming any bytes, this returns (_, _, 0). If
+// the entire frame was consumed, this returns (wr, _, 1). Otherwise, this
+// returns (consumed, rest, 2), where 'consumed' contains the consumed bytes and
+// 'rest' contains the remaining bytes. The consumed bytes are deducted from the
+// underlying stream's flow control budget.
+func (wr FrameWriteRequest) Consume(n int32) (FrameWriteRequest, FrameWriteRequest, int) {
+	var empty FrameWriteRequest
+
+	// Non-DATA frames are always consumed whole.
+	wd, ok := wr.write.(*writeData)
+	if !ok || len(wd.p) == 0 {
+		return wr, empty, 1
+	}
+
+	// Might need to split after applying limits.
+	allowed := wr.stream.flow.available()
+	if n < allowed {
+		allowed = n
+	}
+	if wr.stream.sc.maxFrameSize < allowed {
+		allowed = wr.stream.sc.maxFrameSize
+	}
+	if allowed <= 0 {
+		return empty, empty, 0
+	}
+	if len(wd.p) > int(allowed) {
+		wr.stream.flow.take(allowed)
+		consumed := FrameWriteRequest{
+			stream: wr.stream,
+			write: &writeData{
+				streamID: wd.streamID,
+				p:        wd.p[:allowed],
+				// Even if the original had endStream set, there
+				// are bytes remaining because len(wd.p) > allowed,
+				// so we know endStream is false.
+				endStream: false,
+			},
+			// Our caller is blocking on the final DATA frame, not
+			// this intermediate frame, so no need to wait.
+			done: nil,
+		}
+		rest := FrameWriteRequest{
+			stream: wr.stream,
+			write: &writeData{
+				streamID:  wd.streamID,
+				p:         wd.p[allowed:],
+				endStream: wd.endStream,
+			},
+			done: wr.done,
+		}
+		return consumed, rest, 2
+	}
+
+	// The frame is consumed whole.
+	// NB: This cast cannot overflow because allowed is <= math.MaxInt32.
+	wr.stream.flow.take(int32(len(wd.p)))
+	return wr, empty, 1
+}
+
+// String is for debugging only.
+func (wr FrameWriteRequest) String() string {
+	var des string
+	if s, ok := wr.write.(fmt.Stringer); ok {
+		des = s.String()
+	} else {
+		des = fmt.Sprintf("%T", wr.write)
+	}
+	return fmt.Sprintf("[FrameWriteRequest stream=%d, ch=%v, writer=%v]", wr.StreamID(), wr.done != nil, des)
+}
+
+// replyToWriter sends err to wr.done and panics if the send must block
+// This does nothing if wr.done is nil.
+func (wr *FrameWriteRequest) replyToWriter(err error) {
+	if wr.done == nil {
 		return
 	}
-	delete(ws.sq, id)
-
-	// But keep it for others later.
-	for i := range q.s {
-		q.s[i] = frameWriteMsg{}
+	select {
+	case wr.done <- err:
+	default:
+		panic(fmt.Sprintf("unbuffered done channel passed in for type %T", wr.write))
 	}
-	q.s = q.s[:0]
-	ws.putEmptyQueue(q)
+	wr.write = nil // prevent use (assume it's tainted after wr.done send)
 }
 
+// writeQueue is used by implementations of WriteScheduler.
 type writeQueue struct {
-	s []frameWriteMsg
+	s []FrameWriteRequest
 }
 
-// streamID returns the stream ID for a non-empty stream-specific queue.
-func (q *writeQueue) streamID() uint32 { return q.s[0].stream.id }
-
 func (q *writeQueue) empty() bool { return len(q.s) == 0 }
 
-func (q *writeQueue) push(wm frameWriteMsg) {
-	q.s = append(q.s, wm)
+func (q *writeQueue) push(wr FrameWriteRequest) {
+	q.s = append(q.s, wr)
 }
 
-// head returns the next item that would be removed by shift.
-func (q *writeQueue) head() frameWriteMsg {
+func (q *writeQueue) shift() FrameWriteRequest {
 	if len(q.s) == 0 {
 		panic("invalid use of queue")
 	}
-	return q.s[0]
-}
-
-func (q *writeQueue) shift() frameWriteMsg {
-	if len(q.s) == 0 {
-		panic("invalid use of queue")
-	}
-	wm := q.s[0]
+	wr := q.s[0]
 	// TODO: less copy-happy queue.
 	copy(q.s, q.s[1:])
-	q.s[len(q.s)-1] = frameWriteMsg{}
+	q.s[len(q.s)-1] = FrameWriteRequest{}
 	q.s = q.s[:len(q.s)-1]
-	return wm
+	return wr
 }
 
-func (q *writeQueue) firstIsNoCost() bool {
-	if df, ok := q.s[0].write.(*writeData); ok {
-		return len(df.p) == 0
+// consume consumes up to n bytes from q.s[0]. If the frame is
+// entirely consumed, it is removed from the queue. If the frame
+// is partially consumed, the frame is kept with the consumed
+// bytes removed. Returns true iff any bytes were consumed.
+func (q *writeQueue) consume(n int32) (FrameWriteRequest, bool) {
+	if len(q.s) == 0 {
+		return FrameWriteRequest{}, false
 	}
-	return true
+	consumed, rest, numresult := q.s[0].Consume(n)
+	switch numresult {
+	case 0:
+		return FrameWriteRequest{}, false
+	case 1:
+		q.shift()
+	case 2:
+		q.s[0] = rest
+	}
+	return consumed, true
+}
+
+type writeQueuePool []*writeQueue
+
+// put inserts an unused writeQueue into the pool.
+func (p *writeQueuePool) put(q *writeQueue) {
+	for i := range q.s {
+		q.s[i] = FrameWriteRequest{}
+	}
+	q.s = q.s[:0]
+	*p = append(*p, q)
+}
+
+// get returns an empty writeQueue.
+func (p *writeQueuePool) get() *writeQueue {
+	ln := len(*p)
+	if ln == 0 {
+		return new(writeQueue)
+	}
+	x := ln - 1
+	q := (*p)[x]
+	(*p)[x] = nil
+	*p = (*p)[:x]
+	return q
 }

vendor/golang.org/x/net/http2/writesched_priority.go

@@ -0,0 +1,452 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package http2
+
+import (
+	"fmt"
+	"math"
+	"sort"
+)
+
+// RFC 7540, Section 5.3.5: the default weight is 16.
+const priorityDefaultWeight = 15 // 16 = 15 + 1
+
+// PriorityWriteSchedulerConfig configures a priorityWriteScheduler.
+type PriorityWriteSchedulerConfig struct {
+	// MaxClosedNodesInTree controls the maximum number of closed streams to
+	// retain in the priority tree. Setting this to zero saves a small amount
+	// of memory at the cost of performance.
+	//
+	// See RFC 7540, Section 5.3.4:
+	//   "It is possible for a stream to become closed while prioritization
+	//   information ... is in transit. ... This potentially creates suboptimal
+	//   prioritization, since the stream could be given a priority that is
+	//   different from what is intended. To avoid these problems, an endpoint
+	//   SHOULD retain stream prioritization state for a period after streams
+	//   become closed. The longer state is retained, the lower the chance that
+	//   streams are assigned incorrect or default priority values."
+	MaxClosedNodesInTree int
+
+	// MaxIdleNodesInTree controls the maximum number of idle streams to
+	// retain in the priority tree. Setting this to zero saves a small amount
+	// of memory at the cost of performance.
+	//
+	// See RFC 7540, Section 5.3.4:
+	//   Similarly, streams that are in the "idle" state can be assigned
+	//   priority or become a parent of other streams. This allows for the
+	//   creation of a grouping node in the dependency tree, which enables
+	//   more flexible expressions of priority. Idle streams begin with a
+	//   default priority (Section 5.3.5).
+	MaxIdleNodesInTree int
+
+	// ThrottleOutOfOrderWrites enables write throttling to help ensure that
+	// data is delivered in priority order. This works around a race where
+	// stream B depends on stream A and both streams are about to call Write
+	// to queue DATA frames. If B wins the race, a naive scheduler would eagerly
+	// write as much data from B as possible, but this is suboptimal because A
+	// is a higher-priority stream. With throttling enabled, we write a small
+	// amount of data from B to minimize the amount of bandwidth that B can
+	// steal from A.
+	ThrottleOutOfOrderWrites bool
+}
+
+// NewPriorityWriteScheduler constructs a WriteScheduler that schedules
+// frames by following HTTP/2 priorities as described in RFC 7340 Section 5.3.
+// If cfg is nil, default options are used.
+func NewPriorityWriteScheduler(cfg *PriorityWriteSchedulerConfig) WriteScheduler {
+	if cfg == nil {
+		// For justification of these defaults, see:
+		// https://docs.google.com/document/d/1oLhNg1skaWD4_DtaoCxdSRN5erEXrH-KnLrMwEpOtFY
+		cfg = &PriorityWriteSchedulerConfig{
+			MaxClosedNodesInTree:     10,
+			MaxIdleNodesInTree:       10,
+			ThrottleOutOfOrderWrites: false,
+		}
+	}
+
+	ws := &priorityWriteScheduler{
+		nodes:                make(map[uint32]*priorityNode),
+		maxClosedNodesInTree: cfg.MaxClosedNodesInTree,
+		maxIdleNodesInTree:   cfg.MaxIdleNodesInTree,
+		enableWriteThrottle:  cfg.ThrottleOutOfOrderWrites,
+	}
+	ws.nodes[0] = &ws.root
+	if cfg.ThrottleOutOfOrderWrites {
+		ws.writeThrottleLimit = 1024
+	} else {
+		ws.writeThrottleLimit = math.MaxInt32
+	}
+	return ws
+}
+
+type priorityNodeState int
+
+const (
+	priorityNodeOpen priorityNodeState = iota
+	priorityNodeClosed
+	priorityNodeIdle
+)
+
+// priorityNode is a node in an HTTP/2 priority tree.
+// Each node is associated with a single stream ID.
+// See RFC 7540, Section 5.3.
+type priorityNode struct {
+	q            writeQueue        // queue of pending frames to write
+	id           uint32            // id of the stream, or 0 for the root of the tree
+	weight       uint8             // the actual weight is weight+1, so the value is in [1,256]
+	state        priorityNodeState // open | closed | idle
+	bytes        int64             // number of bytes written by this node, or 0 if closed
+	subtreeBytes int64             // sum(node.bytes) of all nodes in this subtree
+
+	// These links form the priority tree.
+	parent     *priorityNode
+	kids       *priorityNode // start of the kids list
+	prev, next *priorityNode // doubly-linked list of siblings
+}
+
+func (n *priorityNode) setParent(parent *priorityNode) {
+	if n == parent {
+		panic("setParent to self")
+	}
+	if n.parent == parent {
+		return
+	}
+	// Unlink from current parent.
+	if parent := n.parent; parent != nil {
+		if n.prev == nil {
+			parent.kids = n.next
+		} else {
+			n.prev.next = n.next
+		}
+		if n.next != nil {
+			n.next.prev = n.prev
+		}
+	}
+	// Link to new parent.
+	// If parent=nil, remove n from the tree.
+	// Always insert at the head of parent.kids (this is assumed by walkReadyInOrder).
+	n.parent = parent
+	if parent == nil {
+		n.next = nil
+		n.prev = nil
+	} else {
+		n.next = parent.kids
+		n.prev = nil
+		if n.next != nil {
+			n.next.prev = n
+		}
+		parent.kids = n
+	}
+}
+
+func (n *priorityNode) addBytes(b int64) {
+	n.bytes += b
+	for ; n != nil; n = n.parent {
+		n.subtreeBytes += b
+	}
+}
+
+// walkReadyInOrder iterates over the tree in priority order, calling f for each node
+// with a non-empty write queue. When f returns true, this funcion returns true and the
+// walk halts. tmp is used as scratch space for sorting.
+//
+// f(n, openParent) takes two arguments: the node to visit, n, and a bool that is true
+// if any ancestor p of n is still open (ignoring the root node).
+func (n *priorityNode) walkReadyInOrder(openParent bool, tmp *[]*priorityNode, f func(*priorityNode, bool) bool) bool {
+	if !n.q.empty() && f(n, openParent) {
+		return true
+	}
+	if n.kids == nil {
+		return false
+	}
+
+	// Don't consider the root "open" when updating openParent since
+	// we can't send data frames on the root stream (only control frames).
+	if n.id != 0 {
+		openParent = openParent || (n.state == priorityNodeOpen)
+	}
+
+	// Common case: only one kid or all kids have the same weight.
+	// Some clients don't use weights; other clients (like web browsers)
+	// use mostly-linear priority trees.
+	w := n.kids.weight
+	needSort := false
+	for k := n.kids.next; k != nil; k = k.next {
+		if k.weight != w {
+			needSort = true
+			break
+		}
+	}
+	if !needSort {
+		for k := n.kids; k != nil; k = k.next {
+			if k.walkReadyInOrder(openParent, tmp, f) {
+				return true
+			}
+		}
+		return false
+	}
+
+	// Uncommon case: sort the child nodes. We remove the kids from the parent,
+	// then re-insert after sorting so we can reuse tmp for future sort calls.
+	*tmp = (*tmp)[:0]
+	for n.kids != nil {
+		*tmp = append(*tmp, n.kids)
+		n.kids.setParent(nil)
+	}
+	sort.Sort(sortPriorityNodeSiblings(*tmp))
+	for i := len(*tmp) - 1; i >= 0; i-- {
+		(*tmp)[i].setParent(n) // setParent inserts at the head of n.kids
+	}
+	for k := n.kids; k != nil; k = k.next {
+		if k.walkReadyInOrder(openParent, tmp, f) {
+			return true
+		}
+	}
+	return false
+}
+
+type sortPriorityNodeSiblings []*priorityNode
+
+func (z sortPriorityNodeSiblings) Len() int      { return len(z) }
+func (z sortPriorityNodeSiblings) Swap(i, k int) { z[i], z[k] = z[k], z[i] }
+func (z sortPriorityNodeSiblings) Less(i, k int) bool {
+	// Prefer the subtree that has sent fewer bytes relative to its weight.
+	// See sections 5.3.2 and 5.3.4.
+	wi, bi := float64(z[i].weight+1), float64(z[i].subtreeBytes)
+	wk, bk := float64(z[k].weight+1), float64(z[k].subtreeBytes)
+	if bi == 0 && bk == 0 {
+		return wi >= wk
+	}
+	if bk == 0 {
+		return false
+	}
+	return bi/bk <= wi/wk
+}
+
+type priorityWriteScheduler struct {
+	// root is the root of the priority tree, where root.id = 0.
+	// The root queues control frames that are not associated with any stream.
+	root priorityNode
+
+	// nodes maps stream ids to priority tree nodes.
+	nodes map[uint32]*priorityNode
+
+	// maxID is the maximum stream id in nodes.
+	maxID uint32
+
+	// lists of nodes that have been closed or are idle, but are kept in
+	// the tree for improved prioritization. When the lengths exceed either
+	// maxClosedNodesInTree or maxIdleNodesInTree, old nodes are discarded.
+	closedNodes, idleNodes []*priorityNode
+
+	// From the config.
+	maxClosedNodesInTree int
+	maxIdleNodesInTree   int
+	writeThrottleLimit   int32
+	enableWriteThrottle  bool
+
+	// tmp is scratch space for priorityNode.walkReadyInOrder to reduce allocations.
+	tmp []*priorityNode
+
+	// pool of empty queues for reuse.
+	queuePool writeQueuePool
+}
+
+func (ws *priorityWriteScheduler) OpenStream(streamID uint32, options OpenStreamOptions) {
+	// The stream may be currently idle but cannot be opened or closed.
+	if curr := ws.nodes[streamID]; curr != nil {
+		if curr.state != priorityNodeIdle {
+			panic(fmt.Sprintf("stream %d already opened", streamID))
+		}
+		curr.state = priorityNodeOpen
+		return
+	}
+
+	// RFC 7540, Section 5.3.5:
+	//  "All streams are initially assigned a non-exclusive dependency on stream 0x0.
+	//  Pushed streams initially depend on their associated stream. In both cases,
+	//  streams are assigned a default weight of 16."
+	parent := ws.nodes[options.PusherID]
+	if parent == nil {
+		parent = &ws.root
+	}
+	n := &priorityNode{
+		q:      *ws.queuePool.get(),
+		id:     streamID,
+		weight: priorityDefaultWeight,
+		state:  priorityNodeOpen,
+	}
+	n.setParent(parent)
+	ws.nodes[streamID] = n
+	if streamID > ws.maxID {
+		ws.maxID = streamID
+	}
+}
+
+func (ws *priorityWriteScheduler) CloseStream(streamID uint32) {
+	if streamID == 0 {
+		panic("violation of WriteScheduler interface: cannot close stream 0")
+	}
+	if ws.nodes[streamID] == nil {
+		panic(fmt.Sprintf("violation of WriteScheduler interface: unknown stream %d", streamID))
+	}
+	if ws.nodes[streamID].state != priorityNodeOpen {
+		panic(fmt.Sprintf("violation of WriteScheduler interface: stream %d already closed", streamID))
+	}
+
+	n := ws.nodes[streamID]
+	n.state = priorityNodeClosed
+	n.addBytes(-n.bytes)
+
+	q := n.q
+	ws.queuePool.put(&q)
+	n.q.s = nil
+	if ws.maxClosedNodesInTree > 0 {
+		ws.addClosedOrIdleNode(&ws.closedNodes, ws.maxClosedNodesInTree, n)
+	} else {
+		ws.removeNode(n)
+	}
+}
+
+func (ws *priorityWriteScheduler) AdjustStream(streamID uint32, priority PriorityParam) {
+	if streamID == 0 {
+		panic("adjustPriority on root")
+	}
+
+	// If streamID does not exist, there are two cases:
+	// - A closed stream that has been removed (this will have ID <= maxID)
+	// - An idle stream that is being used for "grouping" (this will have ID > maxID)
+	n := ws.nodes[streamID]
+	if n == nil {
+		if streamID <= ws.maxID || ws.maxIdleNodesInTree == 0 {
+			return
+		}
+		ws.maxID = streamID
+		n = &priorityNode{
+			q:      *ws.queuePool.get(),
+			id:     streamID,
+			weight: priorityDefaultWeight,
+			state:  priorityNodeIdle,
+		}
+		n.setParent(&ws.root)
+		ws.nodes[streamID] = n
+		ws.addClosedOrIdleNode(&ws.idleNodes, ws.maxIdleNodesInTree, n)
+	}
+
+	// Section 5.3.1: A dependency on a stream that is not currently in the tree
+	// results in that stream being given a default priority (Section 5.3.5).
+	parent := ws.nodes[priority.StreamDep]
+	if parent == nil {
+		n.setParent(&ws.root)
+		n.weight = priorityDefaultWeight
+		return
+	}
+
+	// Ignore if the client tries to make a node its own parent.
+	if n == parent {
+		return
+	}
+
+	// Section 5.3.3:
+	//   "If a stream is made dependent on one of its own dependencies, the
+	//   formerly dependent stream is first moved to be dependent on the
+	//   reprioritized stream's previous parent. The moved dependency retains
+	//   its weight."
+	//
+	// That is: if parent depends on n, move parent to depend on n.parent.
+	for x := parent.parent; x != nil; x = x.parent {
+		if x == n {
+			parent.setParent(n.parent)
+			break
+		}
+	}
+
+	// Section 5.3.3: The exclusive flag causes the stream to become the sole
+	// dependency of its parent stream, causing other dependencies to become
+	// dependent on the exclusive stream.
+	if priority.Exclusive {
+		k := parent.kids
+		for k != nil {
+			next := k.next
+			if k != n {
+				k.setParent(n)
+			}
+			k = next
+		}
+	}
+
+	n.setParent(parent)
+	n.weight = priority.Weight
+}
+
+func (ws *priorityWriteScheduler) Push(wr FrameWriteRequest) {
+	var n *priorityNode
+	if id := wr.StreamID(); id == 0 {
+		n = &ws.root
+	} else {
+		n = ws.nodes[id]
+		if n == nil {
+			// id is an idle or closed stream. wr should not be a HEADERS or
+			// DATA frame. However, wr can be a RST_STREAM. In this case, we
+			// push wr onto the root, rather than creating a new priorityNode,
+			// since RST_STREAM is tiny and the stream's priority is unknown
+			// anyway. See issue #17919.
+			if wr.DataSize() > 0 {
+				panic("add DATA on non-open stream")
+			}
+			n = &ws.root
+		}
+	}
+	n.q.push(wr)
+}
+
+func (ws *priorityWriteScheduler) Pop() (wr FrameWriteRequest, ok bool) {
+	ws.root.walkReadyInOrder(false, &ws.tmp, func(n *priorityNode, openParent bool) bool {
+		limit := int32(math.MaxInt32)
+		if openParent {
+			limit = ws.writeThrottleLimit
+		}
+		wr, ok = n.q.consume(limit)
+		if !ok {
+			return false
+		}
+		n.addBytes(int64(wr.DataSize()))
+		// If B depends on A and B continuously has data available but A
+		// does not, gradually increase the throttling limit to allow B to
+		// steal more and more bandwidth from A.
+		if openParent {
+			ws.writeThrottleLimit += 1024
+			if ws.writeThrottleLimit < 0 {
+				ws.writeThrottleLimit = math.MaxInt32
+			}
+		} else if ws.enableWriteThrottle {
+			ws.writeThrottleLimit = 1024
+		}
+		return true
+	})
+	return wr, ok
+}
+
+func (ws *priorityWriteScheduler) addClosedOrIdleNode(list *[]*priorityNode, maxSize int, n *priorityNode) {
+	if maxSize == 0 {
+		return
+	}
+	if len(*list) == maxSize {
+		// Remove the oldest node, then shift left.
+		ws.removeNode((*list)[0])
+		x := (*list)[1:]
+		copy(*list, x)
+		*list = (*list)[:len(x)]
+	}
+	*list = append(*list, n)
+}
+
+func (ws *priorityWriteScheduler) removeNode(n *priorityNode) {
+	for k := n.kids; k != nil; k = k.next {
+		k.setParent(n.parent)
+	}
+	n.setParent(nil)
+	delete(ws.nodes, n.id)
+}

vendor/golang.org/x/net/http2/writesched_random.go

@@ -0,0 +1,72 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package http2
+
+import "math"
+
+// NewRandomWriteScheduler constructs a WriteScheduler that ignores HTTP/2
+// priorities. Control frames like SETTINGS and PING are written before DATA
+// frames, but if no control frames are queued and multiple streams have queued
+// HEADERS or DATA frames, Pop selects a ready stream arbitrarily.
+func NewRandomWriteScheduler() WriteScheduler {
+	return &randomWriteScheduler{sq: make(map[uint32]*writeQueue)}
+}
+
+type randomWriteScheduler struct {
+	// zero are frames not associated with a specific stream.
+	zero writeQueue
+
+	// sq contains the stream-specific queues, keyed by stream ID.
+	// When a stream is idle or closed, it's deleted from the map.
+	sq map[uint32]*writeQueue
+
+	// pool of empty queues for reuse.
+	queuePool writeQueuePool
+}
+
+func (ws *randomWriteScheduler) OpenStream(streamID uint32, options OpenStreamOptions) {
+	// no-op: idle streams are not tracked
+}
+
+func (ws *randomWriteScheduler) CloseStream(streamID uint32) {
+	q, ok := ws.sq[streamID]
+	if !ok {
+		return
+	}
+	delete(ws.sq, streamID)
+	ws.queuePool.put(q)
+}
+
+func (ws *randomWriteScheduler) AdjustStream(streamID uint32, priority PriorityParam) {
+	// no-op: priorities are ignored
+}
+
+func (ws *randomWriteScheduler) Push(wr FrameWriteRequest) {
+	id := wr.StreamID()
+	if id == 0 {
+		ws.zero.push(wr)
+		return
+	}
+	q, ok := ws.sq[id]
+	if !ok {
+		q = ws.queuePool.get()
+		ws.sq[id] = q
+	}
+	q.push(wr)
+}
+
+func (ws *randomWriteScheduler) Pop() (FrameWriteRequest, bool) {
+	// Control frames first.
+	if !ws.zero.empty() {
+		return ws.zero.shift(), true
+	}
+	// Iterate over all non-idle streams until finding one that can be consumed.
+	for _, q := range ws.sq {
+		if wr, ok := q.consume(math.MaxInt32); ok {
+			return wr, true
+		}
+	}
+	return FrameWriteRequest{}, false
+}

vendor/golang.org/x/net/idna/idna.go

@@ -0,0 +1,668 @@
+// Code generated by running "go generate" in golang.org/x/text. DO NOT EDIT.
+
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package idna implements IDNA2008 using the compatibility processing
+// defined by UTS (Unicode Technical Standard) #46, which defines a standard to
+// deal with the transition from IDNA2003.
+//
+// IDNA2008 (Internationalized Domain Names for Applications), is defined in RFC
+// 5890, RFC 5891, RFC 5892, RFC 5893 and RFC 5894.
+// UTS #46 is defined in http://www.unicode.org/reports/tr46.
+// See http://unicode.org/cldr/utility/idna.jsp for a visualization of the
+// differences between these two standards.
+package idna // import "golang.org/x/net/idna"
+
+import (
+	"fmt"
+	"strings"
+	"unicode/utf8"
+
+	"golang.org/x/text/secure/bidirule"
+	"golang.org/x/text/unicode/norm"
+)
+
+// NOTE: Unlike common practice in Go APIs, the functions will return a
+// sanitized domain name in case of errors. Browsers sometimes use a partially
+// evaluated string as lookup.
+// TODO: the current error handling is, in my opinion, the least opinionated.
+// Other strategies are also viable, though:
+// Option 1) Return an empty string in case of error, but allow the user to
+//    specify explicitly which errors to ignore.
+// Option 2) Return the partially evaluated string if it is itself a valid
+//    string, otherwise return the empty string in case of error.
+// Option 3) Option 1 and 2.
+// Option 4) Always return an empty string for now and implement Option 1 as
+//    needed, and document that the return string may not be empty in case of
+//    error in the future.
+// I think Option 1 is best, but it is quite opinionated.
+
+// ToASCII is a wrapper for Punycode.ToASCII.
+func ToASCII(s string) (string, error) {
+	return Punycode.process(s, true)
+}
+
+// ToUnicode is a wrapper for Punycode.ToUnicode.
+func ToUnicode(s string) (string, error) {
+	return Punycode.process(s, false)
+}
+
+// An Option configures a Profile at creation time.
+type Option func(*options)
+
+// Transitional sets a Profile to use the Transitional mapping as defined in UTS
+// #46. This will cause, for example, "ß" to be mapped to "ss". Using the
+// transitional mapping provides a compromise between IDNA2003 and IDNA2008
+// compatibility. It is used by most browsers when resolving domain names. This
+// option is only meaningful if combined with MapForLookup.
+func Transitional(transitional bool) Option {
+	return func(o *options) { o.transitional = true }
+}
+
+// VerifyDNSLength sets whether a Profile should fail if any of the IDN parts
+// are longer than allowed by the RFC.
+func VerifyDNSLength(verify bool) Option {
+	return func(o *options) { o.verifyDNSLength = verify }
+}
+
+// ValidateLabels sets whether to check the mandatory label validation criteria
+// as defined in Section 5.4 of RFC 5891. This includes testing for correct use
+// of hyphens ('-'), normalization, validity of runes, and the context rules.
+func ValidateLabels(enable bool) Option {
+	return func(o *options) {
+		// Don't override existing mappings, but set one that at least checks
+		// normalization if it is not set.
+		if o.mapping == nil && enable {
+			o.mapping = normalize
+		}
+		o.trie = trie
+		o.validateLabels = enable
+		o.fromPuny = validateFromPunycode
+	}
+}
+
+// StrictDomainName limits the set of permissable ASCII characters to those
+// allowed in domain names as defined in RFC 1034 (A-Z, a-z, 0-9 and the
+// hyphen). This is set by default for MapForLookup and ValidateForRegistration.
+//
+// This option is useful, for instance, for browsers that allow characters
+// outside this range, for example a '_' (U+005F LOW LINE). See
+// http://www.rfc-editor.org/std/std3.txt for more details This option
+// corresponds to the UseSTD3ASCIIRules option in UTS #46.
+func StrictDomainName(use bool) Option {
+	return func(o *options) {
+		o.trie = trie
+		o.useSTD3Rules = use
+		o.fromPuny = validateFromPunycode
+	}
+}
+
+// NOTE: the following options pull in tables. The tables should not be linked
+// in as long as the options are not used.
+
+// BidiRule enables the Bidi rule as defined in RFC 5893. Any application
+// that relies on proper validation of labels should include this rule.
+func BidiRule() Option {
+	return func(o *options) { o.bidirule = bidirule.ValidString }
+}
+
+// ValidateForRegistration sets validation options to verify that a given IDN is
+// properly formatted for registration as defined by Section 4 of RFC 5891.
+func ValidateForRegistration() Option {
+	return func(o *options) {
+		o.mapping = validateRegistration
+		StrictDomainName(true)(o)
+		ValidateLabels(true)(o)
+		VerifyDNSLength(true)(o)
+		BidiRule()(o)
+	}
+}
+
+// MapForLookup sets validation and mapping options such that a given IDN is
+// transformed for domain name lookup according to the requirements set out in
+// Section 5 of RFC 5891. The mappings follow the recommendations of RFC 5894,
+// RFC 5895 and UTS 46. It does not add the Bidi Rule. Use the BidiRule option
+// to add this check.
+//
+// The mappings include normalization and mapping case, width and other
+// compatibility mappings.
+func MapForLookup() Option {
+	return func(o *options) {
+		o.mapping = validateAndMap
+		StrictDomainName(true)(o)
+		ValidateLabels(true)(o)
+	}
+}
+
+type options struct {
+	transitional    bool
+	useSTD3Rules    bool
+	validateLabels  bool
+	verifyDNSLength bool
+
+	trie *idnaTrie
+
+	// fromPuny calls validation rules when converting A-labels to U-labels.
+	fromPuny func(p *Profile, s string) error
+
+	// mapping implements a validation and mapping step as defined in RFC 5895
+	// or UTS 46, tailored to, for example, domain registration or lookup.
+	mapping func(p *Profile, s string) (string, error)
+
+	// bidirule, if specified, checks whether s conforms to the Bidi Rule
+	// defined in RFC 5893.
+	bidirule func(s string) bool
+}
+
+// A Profile defines the configuration of a IDNA mapper.
+type Profile struct {
+	options
+}
+
+func apply(o *options, opts []Option) {
+	for _, f := range opts {
+		f(o)
+	}
+}
+
+// New creates a new Profile.
+//
+// With no options, the returned Profile is the most permissive and equals the
+// Punycode Profile. Options can be passed to further restrict the Profile. The
+// MapForLookup and ValidateForRegistration options set a collection of options,
+// for lookup and registration purposes respectively, which can be tailored by
+// adding more fine-grained options, where later options override earlier
+// options.
+func New(o ...Option) *Profile {
+	p := &Profile{}
+	apply(&p.options, o)
+	return p
+}
+
+// ToASCII converts a domain or domain label to its ASCII form. For example,
+// ToASCII("bücher.example.com") is "xn--bcher-kva.example.com", and
+// ToASCII("golang") is "golang". If an error is encountered it will return
+// an error and a (partially) processed result.
+func (p *Profile) ToASCII(s string) (string, error) {
+	return p.process(s, true)
+}
+
+// ToUnicode converts a domain or domain label to its Unicode form. For example,
+// ToUnicode("xn--bcher-kva.example.com") is "bücher.example.com", and
+// ToUnicode("golang") is "golang". If an error is encountered it will return
+// an error and a (partially) processed result.
+func (p *Profile) ToUnicode(s string) (string, error) {
+	pp := *p
+	pp.transitional = false
+	return pp.process(s, false)
+}
+
+// String reports a string with a description of the profile for debugging
+// purposes. The string format may change with different versions.
+func (p *Profile) String() string {
+	s := ""
+	if p.transitional {
+		s = "Transitional"
+	} else {
+		s = "NonTransitional"
+	}
+	if p.useSTD3Rules {
+		s += ":UseSTD3Rules"
+	}
+	if p.validateLabels {
+		s += ":ValidateLabels"
+	}
+	if p.verifyDNSLength {
+		s += ":VerifyDNSLength"
+	}
+	return s
+}
+
+var (
+	// Punycode is a Profile that does raw punycode processing with a minimum
+	// of validation.
+	Punycode *Profile = punycode
+
+	// Lookup is the recommended profile for looking up domain names, according
+	// to Section 5 of RFC 5891. The exact configuration of this profile may
+	// change over time.
+	Lookup *Profile = lookup
+
+	// Display is the recommended profile for displaying domain names.
+	// The configuration of this profile may change over time.
+	Display *Profile = display
+
+	// Registration is the recommended profile for checking whether a given
+	// IDN is valid for registration, according to Section 4 of RFC 5891.
+	Registration *Profile = registration
+
+	punycode = &Profile{}
+	lookup   = &Profile{options{
+		transitional:   true,
+		useSTD3Rules:   true,
+		validateLabels: true,
+		trie:           trie,
+		fromPuny:       validateFromPunycode,
+		mapping:        validateAndMap,
+		bidirule:       bidirule.ValidString,
+	}}
+	display = &Profile{options{
+		useSTD3Rules:   true,
+		validateLabels: true,
+		trie:           trie,
+		fromPuny:       validateFromPunycode,
+		mapping:        validateAndMap,
+		bidirule:       bidirule.ValidString,
+	}}
+	registration = &Profile{options{
+		useSTD3Rules:    true,
+		validateLabels:  true,
+		verifyDNSLength: true,
+		trie:            trie,
+		fromPuny:        validateFromPunycode,
+		mapping:         validateRegistration,
+		bidirule:        bidirule.ValidString,
+	}}
+
+	// TODO: profiles
+	// Register: recommended for approving domain names: don't do any mappings
+	// but rather reject on invalid input. Bundle or block deviation characters.
+)
+
+type labelError struct{ label, code_ string }
+
+func (e labelError) code() string { return e.code_ }
+func (e labelError) Error() string {
+	return fmt.Sprintf("idna: invalid label %q", e.label)
+}
+
+type runeError rune
+
+func (e runeError) code() string { return "P1" }
+func (e runeError) Error() string {
+	return fmt.Sprintf("idna: disallowed rune %U", e)
+}
+
+// process implements the algorithm described in section 4 of UTS #46,
+// see http://www.unicode.org/reports/tr46.
+func (p *Profile) process(s string, toASCII bool) (string, error) {
+	var err error
+	if p.mapping != nil {
+		s, err = p.mapping(p, s)
+	}
+	// Remove leading empty labels.
+	for ; len(s) > 0 && s[0] == '.'; s = s[1:] {
+	}
+	// It seems like we should only create this error on ToASCII, but the
+	// UTS 46 conformance tests suggests we should always check this.
+	if err == nil && p.verifyDNSLength && s == "" {
+		err = &labelError{s, "A4"}
+	}
+	labels := labelIter{orig: s}
+	for ; !labels.done(); labels.next() {
+		label := labels.label()
+		if label == "" {
+			// Empty labels are not okay. The label iterator skips the last
+			// label if it is empty.
+			if err == nil && p.verifyDNSLength {
+				err = &labelError{s, "A4"}
+			}
+			continue
+		}
+		if strings.HasPrefix(label, acePrefix) {
+			u, err2 := decode(label[len(acePrefix):])
+			if err2 != nil {
+				if err == nil {
+					err = err2
+				}
+				// Spec says keep the old label.
+				continue
+			}
+			labels.set(u)
+			if err == nil && p.validateLabels {
+				err = p.fromPuny(p, u)
+			}
+			if err == nil {
+				// This should be called on NonTransitional, according to the
+				// spec, but that currently does not have any effect. Use the
+				// original profile to preserve options.
+				err = p.validateLabel(u)
+			}
+		} else if err == nil {
+			err = p.validateLabel(label)
+		}
+	}
+	if toASCII {
+		for labels.reset(); !labels.done(); labels.next() {
+			label := labels.label()
+			if !ascii(label) {
+				a, err2 := encode(acePrefix, label)
+				if err == nil {
+					err = err2
+				}
+				label = a
+				labels.set(a)
+			}
+			n := len(label)
+			if p.verifyDNSLength && err == nil && (n == 0 || n > 63) {
+				err = &labelError{label, "A4"}
+			}
+		}
+	}
+	s = labels.result()
+	if toASCII && p.verifyDNSLength && err == nil {
+		// Compute the length of the domain name minus the root label and its dot.
+		n := len(s)
+		if n > 0 && s[n-1] == '.' {
+			n--
+		}
+		if len(s) < 1 || n > 253 {
+			err = &labelError{s, "A4"}
+		}
+	}
+	return s, err
+}
+
+func normalize(p *Profile, s string) (string, error) {
+	return norm.NFC.String(s), nil
+}
+
+func validateRegistration(p *Profile, s string) (string, error) {
+	if !norm.NFC.IsNormalString(s) {
+		return s, &labelError{s, "V1"}
+	}
+	var err error
+	for i := 0; i < len(s); {
+		v, sz := trie.lookupString(s[i:])
+		i += sz
+		// Copy bytes not copied so far.
+		switch p.simplify(info(v).category()) {
+		// TODO: handle the NV8 defined in the Unicode idna data set to allow
+		// for strict conformance to IDNA2008.
+		case valid, deviation:
+		case disallowed, mapped, unknown, ignored:
+			if err == nil {
+				r, _ := utf8.DecodeRuneInString(s[i:])
+				err = runeError(r)
+			}
+		}
+	}
+	return s, err
+}
+
+func validateAndMap(p *Profile, s string) (string, error) {
+	var (
+		err error
+		b   []byte
+		k   int
+	)
+	for i := 0; i < len(s); {
+		v, sz := trie.lookupString(s[i:])
+		start := i
+		i += sz
+		// Copy bytes not copied so far.
+		switch p.simplify(info(v).category()) {
+		case valid:
+			continue
+		case disallowed:
+			if err == nil {
+				r, _ := utf8.DecodeRuneInString(s[i:])
+				err = runeError(r)
+			}
+			continue
+		case mapped, deviation:
+			b = append(b, s[k:start]...)
+			b = info(v).appendMapping(b, s[start:i])
+		case ignored:
+			b = append(b, s[k:start]...)
+			// drop the rune
+		case unknown:
+			b = append(b, s[k:start]...)
+			b = append(b, "\ufffd"...)
+		}
+		k = i
+	}
+	if k == 0 {
+		// No changes so far.
+		s = norm.NFC.String(s)
+	} else {
+		b = append(b, s[k:]...)
+		if norm.NFC.QuickSpan(b) != len(b) {
+			b = norm.NFC.Bytes(b)
+		}
+		// TODO: the punycode converters require strings as input.
+		s = string(b)
+	}
+	return s, err
+}
+
+// A labelIter allows iterating over domain name labels.
+type labelIter struct {
+	orig     string
+	slice    []string
+	curStart int
+	curEnd   int
+	i        int
+}
+
+func (l *labelIter) reset() {
+	l.curStart = 0
+	l.curEnd = 0
+	l.i = 0
+}
+
+func (l *labelIter) done() bool {
+	return l.curStart >= len(l.orig)
+}
+
+func (l *labelIter) result() string {
+	if l.slice != nil {
+		return strings.Join(l.slice, ".")
+	}
+	return l.orig
+}
+
+func (l *labelIter) label() string {
+	if l.slice != nil {
+		return l.slice[l.i]
+	}
+	p := strings.IndexByte(l.orig[l.curStart:], '.')
+	l.curEnd = l.curStart + p
+	if p == -1 {
+		l.curEnd = len(l.orig)
+	}
+	return l.orig[l.curStart:l.curEnd]
+}
+
+// next sets the value to the next label. It skips the last label if it is empty.
+func (l *labelIter) next() {
+	l.i++
+	if l.slice != nil {
+		if l.i >= len(l.slice) || l.i == len(l.slice)-1 && l.slice[l.i] == "" {
+			l.curStart = len(l.orig)
+		}
+	} else {
+		l.curStart = l.curEnd + 1
+		if l.curStart == len(l.orig)-1 && l.orig[l.curStart] == '.' {
+			l.curStart = len(l.orig)
+		}
+	}
+}
+
+func (l *labelIter) set(s string) {
+	if l.slice == nil {
+		l.slice = strings.Split(l.orig, ".")
+	}
+	l.slice[l.i] = s
+}
+
+// acePrefix is the ASCII Compatible Encoding prefix.
+const acePrefix = "xn--"
+
+func (p *Profile) simplify(cat category) category {
+	switch cat {
+	case disallowedSTD3Mapped:
+		if p.useSTD3Rules {
+			cat = disallowed
+		} else {
+			cat = mapped
+		}
+	case disallowedSTD3Valid:
+		if p.useSTD3Rules {
+			cat = disallowed
+		} else {
+			cat = valid
+		}
+	case deviation:
+		if !p.transitional {
+			cat = valid
+		}
+	case validNV8, validXV8:
+		// TODO: handle V2008
+		cat = valid
+	}
+	return cat
+}
+
+func validateFromPunycode(p *Profile, s string) error {
+	if !norm.NFC.IsNormalString(s) {
+		return &labelError{s, "V1"}
+	}
+	for i := 0; i < len(s); {
+		v, sz := trie.lookupString(s[i:])
+		if c := p.simplify(info(v).category()); c != valid && c != deviation {
+			return &labelError{s, "V6"}
+		}
+		i += sz
+	}
+	return nil
+}
+
+const (
+	zwnj = "\u200c"
+	zwj  = "\u200d"
+)
+
+type joinState int8
+
+const (
+	stateStart joinState = iota
+	stateVirama
+	stateBefore
+	stateBeforeVirama
+	stateAfter
+	stateFAIL
+)
+
+var joinStates = [][numJoinTypes]joinState{
+	stateStart: {
+		joiningL:   stateBefore,
+		joiningD:   stateBefore,
+		joinZWNJ:   stateFAIL,
+		joinZWJ:    stateFAIL,
+		joinVirama: stateVirama,
+	},
+	stateVirama: {
+		joiningL: stateBefore,
+		joiningD: stateBefore,
+	},
+	stateBefore: {
+		joiningL:   stateBefore,
+		joiningD:   stateBefore,
+		joiningT:   stateBefore,
+		joinZWNJ:   stateAfter,
+		joinZWJ:    stateFAIL,
+		joinVirama: stateBeforeVirama,
+	},
+	stateBeforeVirama: {
+		joiningL: stateBefore,
+		joiningD: stateBefore,
+		joiningT: stateBefore,
+	},
+	stateAfter: {
+		joiningL:   stateFAIL,
+		joiningD:   stateBefore,
+		joiningT:   stateAfter,
+		joiningR:   stateStart,
+		joinZWNJ:   stateFAIL,
+		joinZWJ:    stateFAIL,
+		joinVirama: stateAfter, // no-op as we can't accept joiners here
+	},
+	stateFAIL: {
+		0:          stateFAIL,
+		joiningL:   stateFAIL,
+		joiningD:   stateFAIL,
+		joiningT:   stateFAIL,
+		joiningR:   stateFAIL,
+		joinZWNJ:   stateFAIL,
+		joinZWJ:    stateFAIL,
+		joinVirama: stateFAIL,
+	},
+}
+
+// validateLabel validates the criteria from Section 4.1. Item 1, 4, and 6 are
+// already implicitly satisfied by the overall implementation.
+func (p *Profile) validateLabel(s string) error {
+	if s == "" {
+		if p.verifyDNSLength {
+			return &labelError{s, "A4"}
+		}
+		return nil
+	}
+	if p.bidirule != nil && !p.bidirule(s) {
+		return &labelError{s, "B"}
+	}
+	if !p.validateLabels {
+		return nil
+	}
+	trie := p.trie // p.validateLabels is only set if trie is set.
+	if len(s) > 4 && s[2] == '-' && s[3] == '-' {
+		return &labelError{s, "V2"}
+	}
+	if s[0] == '-' || s[len(s)-1] == '-' {
+		return &labelError{s, "V3"}
+	}
+	// TODO: merge the use of this in the trie.
+	v, sz := trie.lookupString(s)
+	x := info(v)
+	if x.isModifier() {
+		return &labelError{s, "V5"}
+	}
+	// Quickly return in the absence of zero-width (non) joiners.
+	if strings.Index(s, zwj) == -1 && strings.Index(s, zwnj) == -1 {
+		return nil
+	}
+	st := stateStart
+	for i := 0; ; {
+		jt := x.joinType()
+		if s[i:i+sz] == zwj {
+			jt = joinZWJ
+		} else if s[i:i+sz] == zwnj {
+			jt = joinZWNJ
+		}
+		st = joinStates[st][jt]
+		if x.isViramaModifier() {
+			st = joinStates[st][joinVirama]
+		}
+		if i += sz; i == len(s) {
+			break
+		}
+		v, sz = trie.lookupString(s[i:])
+		x = info(v)
+	}
+	if st == stateFAIL || st == stateAfter {
+		return &labelError{s, "C"}
+	}
+	return nil
+}
+
+func ascii(s string) bool {
+	for i := 0; i < len(s); i++ {
+		if s[i] >= utf8.RuneSelf {
+			return false
+		}
+	}
+	return true
+}

vendor/golang.org/x/net/idna/punycode.go

@@ -0,0 +1,203 @@
+// Code generated by running "go generate" in golang.org/x/text. DO NOT EDIT.
+
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package idna
+
+// This file implements the Punycode algorithm from RFC 3492.
+
+import (
+	"math"
+	"strings"
+	"unicode/utf8"
+)
+
+// These parameter values are specified in section 5.
+//
+// All computation is done with int32s, so that overflow behavior is identical
+// regardless of whether int is 32-bit or 64-bit.
+const (
+	base        int32 = 36
+	damp        int32 = 700
+	initialBias int32 = 72
+	initialN    int32 = 128
+	skew        int32 = 38
+	tmax        int32 = 26
+	tmin        int32 = 1
+)
+
+func punyError(s string) error { return &labelError{s, "A3"} }
+
+// decode decodes a string as specified in section 6.2.
+func decode(encoded string) (string, error) {
+	if encoded == "" {
+		return "", nil
+	}
+	pos := 1 + strings.LastIndex(encoded, "-")
+	if pos == 1 {
+		return "", punyError(encoded)
+	}
+	if pos == len(encoded) {
+		return encoded[:len(encoded)-1], nil
+	}
+	output := make([]rune, 0, len(encoded))
+	if pos != 0 {
+		for _, r := range encoded[:pos-1] {
+			output = append(output, r)
+		}
+	}
+	i, n, bias := int32(0), initialN, initialBias
+	for pos < len(encoded) {
+		oldI, w := i, int32(1)
+		for k := base; ; k += base {
+			if pos == len(encoded) {
+				return "", punyError(encoded)
+			}
+			digit, ok := decodeDigit(encoded[pos])
+			if !ok {
+				return "", punyError(encoded)
+			}
+			pos++
+			i += digit * w
+			if i < 0 {
+				return "", punyError(encoded)
+			}
+			t := k - bias
+			if t < tmin {
+				t = tmin
+			} else if t > tmax {
+				t = tmax
+			}
+			if digit < t {
+				break
+			}
+			w *= base - t
+			if w >= math.MaxInt32/base {
+				return "", punyError(encoded)
+			}
+		}
+		x := int32(len(output) + 1)
+		bias = adapt(i-oldI, x, oldI == 0)
+		n += i / x
+		i %= x
+		if n > utf8.MaxRune || len(output) >= 1024 {
+			return "", punyError(encoded)
+		}
+		output = append(output, 0)
+		copy(output[i+1:], output[i:])
+		output[i] = n
+		i++
+	}
+	return string(output), nil
+}
+
+// encode encodes a string as specified in section 6.3 and prepends prefix to
+// the result.
+//
+// The "while h < length(input)" line in the specification becomes "for
+// remaining != 0" in the Go code, because len(s) in Go is in bytes, not runes.
+func encode(prefix, s string) (string, error) {
+	output := make([]byte, len(prefix), len(prefix)+1+2*len(s))
+	copy(output, prefix)
+	delta, n, bias := int32(0), initialN, initialBias
+	b, remaining := int32(0), int32(0)
+	for _, r := range s {
+		if r < 0x80 {
+			b++
+			output = append(output, byte(r))
+		} else {
+			remaining++
+		}
+	}
+	h := b
+	if b > 0 {
+		output = append(output, '-')
+	}
+	for remaining != 0 {
+		m := int32(0x7fffffff)
+		for _, r := range s {
+			if m > r && r >= n {
+				m = r
+			}
+		}
+		delta += (m - n) * (h + 1)
+		if delta < 0 {
+			return "", punyError(s)
+		}
+		n = m
+		for _, r := range s {
+			if r < n {
+				delta++
+				if delta < 0 {
+					return "", punyError(s)
+				}
+				continue
+			}
+			if r > n {
+				continue
+			}
+			q := delta
+			for k := base; ; k += base {
+				t := k - bias
+				if t < tmin {
+					t = tmin
+				} else if t > tmax {
+					t = tmax
+				}
+				if q < t {
+					break
+				}
+				output = append(output, encodeDigit(t+(q-t)%(base-t)))
+				q = (q - t) / (base - t)
+			}
+			output = append(output, encodeDigit(q))
+			bias = adapt(delta, h+1, h == b)
+			delta = 0
+			h++
+			remaining--
+		}
+		delta++
+		n++
+	}
+	return string(output), nil
+}
+
+func decodeDigit(x byte) (digit int32, ok bool) {
+	switch {
+	case '0' <= x && x <= '9':
+		return int32(x - ('0' - 26)), true
+	case 'A' <= x && x <= 'Z':
+		return int32(x - 'A'), true
+	case 'a' <= x && x <= 'z':
+		return int32(x - 'a'), true
+	}
+	return 0, false
+}
+
+func encodeDigit(digit int32) byte {
+	switch {
+	case 0 <= digit && digit < 26:
+		return byte(digit + 'a')
+	case 26 <= digit && digit < 36:
+		return byte(digit + ('0' - 26))
+	}
+	panic("idna: internal error in punycode encoding")
+}
+
+// adapt is the bias adaptation function specified in section 6.1.
+func adapt(delta, numPoints int32, firstTime bool) int32 {
+	if firstTime {
+		delta /= damp
+	} else {
+		delta /= 2
+	}
+	delta += delta / numPoints
+	k := int32(0)
+	for delta > ((base-tmin)*tmax)/2 {
+		delta /= base - tmin
+		k += base
+	}
+	return k + (base-tmin+1)*delta/(delta+skew)
+}

vendor/golang.org/x/net/idna/trie.go

@@ -0,0 +1,72 @@
+// Code generated by running "go generate" in golang.org/x/text. DO NOT EDIT.
+
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package idna
+
+// appendMapping appends the mapping for the respective rune. isMapped must be
+// true. A mapping is a categorization of a rune as defined in UTS #46.
+func (c info) appendMapping(b []byte, s string) []byte {
+	index := int(c >> indexShift)
+	if c&xorBit == 0 {
+		s := mappings[index:]
+		return append(b, s[1:s[0]+1]...)
+	}
+	b = append(b, s...)
+	if c&inlineXOR == inlineXOR {
+		// TODO: support and handle two-byte inline masks
+		b[len(b)-1] ^= byte(index)
+	} else {
+		for p := len(b) - int(xorData[index]); p < len(b); p++ {
+			index++
+			b[p] ^= xorData[index]
+		}
+	}
+	return b
+}
+
+// Sparse block handling code.
+
+type valueRange struct {
+	value  uint16 // header: value:stride
+	lo, hi byte   // header: lo:n
+}
+
+type sparseBlocks struct {
+	values []valueRange
+	offset []uint16
+}
+
+var idnaSparse = sparseBlocks{
+	values: idnaSparseValues[:],
+	offset: idnaSparseOffset[:],
+}
+
+// Don't use newIdnaTrie to avoid unconditional linking in of the table.
+var trie = &idnaTrie{}
+
+// lookup determines the type of block n and looks up the value for b.
+// For n < t.cutoff, the block is a simple lookup table. Otherwise, the block
+// is a list of ranges with an accompanying value. Given a matching range r,
+// the value for b is by r.value + (b - r.lo) * stride.
+func (t *sparseBlocks) lookup(n uint32, b byte) uint16 {
+	offset := t.offset[n]
+	header := t.values[offset]
+	lo := offset + 1
+	hi := lo + uint16(header.lo)
+	for lo < hi {
+		m := lo + (hi-lo)/2
+		r := t.values[m]
+		if r.lo <= b && b <= r.hi {
+			return r.value + uint16(b-r.lo)*header.value
+		}
+		if b < r.lo {
+			hi = m
+		} else {
+			lo = m + 1
+		}
+	}
+	return 0
+}

vendor/golang.org/x/net/idna/trieval.go

@@ -0,0 +1,114 @@
+// Code generated by running "go generate" in golang.org/x/text. DO NOT EDIT.
+
+package idna
+
+// This file contains definitions for interpreting the trie value of the idna
+// trie generated by "go run gen*.go". It is shared by both the generator
+// program and the resultant package. Sharing is achieved by the generator
+// copying gen_trieval.go to trieval.go and changing what's above this comment.
+
+// info holds information from the IDNA mapping table for a single rune. It is
+// the value returned by a trie lookup. In most cases, all information fits in
+// a 16-bit value. For mappings, this value may contain an index into a slice
+// with the mapped string. Such mappings can consist of the actual mapped value
+// or an XOR pattern to be applied to the bytes of the UTF8 encoding of the
+// input rune. This technique is used by the cases packages and reduces the
+// table size significantly.
+//
+// The per-rune values have the following format:
+//
+//   if mapped {
+//     if inlinedXOR {
+//       15..13 inline XOR marker
+//       12..11 unused
+//       10..3  inline XOR mask
+//     } else {
+//       15..3  index into xor or mapping table
+//     }
+//   } else {
+//       15..13 unused
+//           12 modifier (including virama)
+//           11 virama modifier
+//       10..8  joining type
+//        7..3  category type
+//   }
+//      2  use xor pattern
+//   1..0  mapped category
+//
+// See the definitions below for a more detailed description of the various
+// bits.
+type info uint16
+
+const (
+	catSmallMask = 0x3
+	catBigMask   = 0xF8
+	indexShift   = 3
+	xorBit       = 0x4    // interpret the index as an xor pattern
+	inlineXOR    = 0xE000 // These bits are set if the XOR pattern is inlined.
+
+	joinShift = 8
+	joinMask  = 0x07
+
+	viramaModifier = 0x0800
+	modifier       = 0x1000
+)
+
+// A category corresponds to a category defined in the IDNA mapping table.
+type category uint16
+
+const (
+	unknown              category = 0 // not defined currently in unicode.
+	mapped               category = 1
+	disallowedSTD3Mapped category = 2
+	deviation            category = 3
+)
+
+const (
+	valid               category = 0x08
+	validNV8            category = 0x18
+	validXV8            category = 0x28
+	disallowed          category = 0x40
+	disallowedSTD3Valid category = 0x80
+	ignored             category = 0xC0
+)
+
+// join types and additional rune information
+const (
+	joiningL = (iota + 1)
+	joiningD
+	joiningT
+	joiningR
+
+	//the following types are derived during processing
+	joinZWJ
+	joinZWNJ
+	joinVirama
+	numJoinTypes
+)
+
+func (c info) isMapped() bool {
+	return c&0x3 != 0
+}
+
+func (c info) category() category {
+	small := c & catSmallMask
+	if small != 0 {
+		return category(small)
+	}
+	return category(c & catBigMask)
+}
+
+func (c info) joinType() info {
+	if c.isMapped() {
+		return 0
+	}
+	return (c >> joinShift) & joinMask
+}
+
+func (c info) isModifier() bool {
+	return c&(modifier|catSmallMask) == modifier
+}
+
+func (c info) isViramaModifier() bool {
+	return c&(viramaModifier|catSmallMask) == viramaModifier
+}

vendor/golang.org/x/net/internal/timeseries/timeseries.go

@@ -371,7 +371,7 @@ func (ts *timeSeries) ComputeRange(start, finish time.Time, num int) []Observabl
 		}
 	}
 
-	// Failed to find a level that covers the desired range.  So just
+	// Failed to find a level that covers the desired range. So just
 	// extract from the last level, even if it doesn't cover the entire
 	// desired range.
 	ts.extract(ts.levels[len(ts.levels)-1], start, finish, num, results)

vendor/golang.org/x/net/lex/httplex/httplex.go

@@ -10,8 +10,11 @@
 package httplex
 
 import (
+	"net"
 	"strings"
 	"unicode/utf8"
+
+	"golang.org/x/net/idna"
 )
 
 var isTokenTable = [127]bool{
@@ -310,3 +313,39 @@ func ValidHeaderFieldValue(v string) bool {
 	}
 	return true
 }
+
+func isASCII(s string) bool {
+	for i := 0; i < len(s); i++ {
+		if s[i] >= utf8.RuneSelf {
+			return false
+		}
+	}
+	return true
+}
+
+// PunycodeHostPort returns the IDNA Punycode version
+// of the provided "host" or "host:port" string.
+func PunycodeHostPort(v string) (string, error) {
+	if isASCII(v) {
+		return v, nil
+	}
+
+	host, port, err := net.SplitHostPort(v)
+	if err != nil {
+		// The input 'v' argument was just a "host" argument,
+		// without a port. This error should not be returned
+		// to the caller.
+		host = v
+		port = ""
+	}
+	host, err = idna.ToASCII(host)
+	if err != nil {
+		// Non-UTF-8? Not representable in Punycode, in any
+		// case.
+		return "", err
+	}
+	if port == "" {
+		return host, nil
+	}
+	return net.JoinHostPort(host, port), nil
+}

vendor/golang.org/x/net/trace/events.go

@@ -21,11 +21,6 @@ import (
 	"time"
 )
 
-var eventsTmpl = template.Must(template.New("events").Funcs(template.FuncMap{
-	"elapsed":   elapsed,
-	"trimSpace": strings.TrimSpace,
-}).Parse(eventsHTML))
-
 const maxEventsPerLog = 100
 
 type bucket struct {
@@ -101,7 +96,7 @@ func RenderEvents(w http.ResponseWriter, req *http.Request, sensitive bool) {
 
 	famMu.RLock()
 	defer famMu.RUnlock()
-	if err := eventsTmpl.Execute(w, data); err != nil {
+	if err := eventsTmpl().Execute(w, data); err != nil {
 		log.Printf("net/trace: Failed executing template: %v", err)
 	}
 }
@@ -421,6 +416,19 @@ func freeEventLog(el *eventLog) {
 	}
 }
 
+var eventsTmplCache *template.Template
+var eventsTmplOnce sync.Once
+
+func eventsTmpl() *template.Template {
+	eventsTmplOnce.Do(func() {
+		eventsTmplCache = template.Must(template.New("events").Funcs(template.FuncMap{
+			"elapsed":   elapsed,
+			"trimSpace": strings.TrimSpace,
+		}).Parse(eventsHTML))
+	})
+	return eventsTmplCache
+}
+
 const eventsHTML = `
 <html>
 	<head>

vendor/golang.org/x/net/trace/histogram.go

@@ -12,6 +12,7 @@ import (
 	"html/template"
 	"log"
 	"math"
+	"sync"
 
 	"golang.org/x/net/internal/timeseries"
 )
@@ -320,15 +321,20 @@ func (h *histogram) newData() *data {
 
 func (h *histogram) html() template.HTML {
 	buf := new(bytes.Buffer)
-	if err := distTmpl.Execute(buf, h.newData()); err != nil {
+	if err := distTmpl().Execute(buf, h.newData()); err != nil {
 		buf.Reset()
 		log.Printf("net/trace: couldn't execute template: %v", err)
 	}
 	return template.HTML(buf.String())
 }
 
-// Input: data
-var distTmpl = template.Must(template.New("distTmpl").Parse(`
+var distTmplCache *template.Template
+var distTmplOnce sync.Once
+
+func distTmpl() *template.Template {
+	distTmplOnce.Do(func() {
+		// Input: data
+		distTmplCache = template.Must(template.New("distTmpl").Parse(`
 <table>
 <tr>
     <td style="padding:0.25em">Count: {{.Count}}</td>
@@ -354,3 +360,6 @@ var distTmpl = template.Must(template.New("distTmpl").Parse(`
 {{end}}
 </table>
 `))
+	})
+	return distTmplCache
+}

vendor/golang.org/x/net/trace/trace.go

@@ -91,7 +91,7 @@ var DebugUseAfterFinish = false
 // It returns two bools; the first indicates whether the page may be viewed at all,
 // and the second indicates whether sensitive events will be shown.
 //
-// AuthRequest may be replaced by a program to customise its authorisation requirements.
+// AuthRequest may be replaced by a program to customize its authorization requirements.
 //
 // The default AuthRequest function returns (true, true) if and only if the request
 // comes from localhost/127.0.0.1/[::1].
@@ -238,7 +238,7 @@ func Render(w io.Writer, req *http.Request, sensitive bool) {
 
 	completedMu.RLock()
 	defer completedMu.RUnlock()
-	if err := pageTmpl.ExecuteTemplate(w, "Page", data); err != nil {
+	if err := pageTmpl().ExecuteTemplate(w, "Page", data); err != nil {
 		log.Printf("net/trace: Failed executing template: %v", err)
 	}
 }
@@ -333,7 +333,8 @@ func New(family, title string) Trace {
 	tr.ref()
 	tr.Family, tr.Title = family, title
 	tr.Start = time.Now()
-	tr.events = make([]event, 0, maxEventsPerTrace)
+	tr.maxEvents = maxEventsPerTrace
+	tr.events = tr.eventsBuf[:0]
 
 	activeMu.RLock()
 	s := activeTraces[tr.Family]
@@ -650,8 +651,8 @@ type event struct {
 	Elapsed    time.Duration // since previous event in trace
 	NewDay     bool          // whether this event is on a different day to the previous event
 	Recyclable bool          // whether this event was passed via LazyLog
-	What       interface{}   // string or fmt.Stringer
 	Sensitive  bool          // whether this event contains sensitive information
+	What       interface{}   // string or fmt.Stringer
 }
 
 // WhenString returns a string representation of the elapsed time of the event.
@@ -692,14 +693,17 @@ type trace struct {
 	IsError bool
 
 	// Append-only sequence of events (modulo discards).
-	mu     sync.RWMutex
-	events []event
+	mu        sync.RWMutex
+	events    []event
+	maxEvents int
 
 	refs     int32 // how many buckets this is in
 	recycler func(interface{})
 	disc     discarded // scratch space to avoid allocation
 
 	finishStack []byte // where finish was called, if DebugUseAfterFinish is set
+
+	eventsBuf [4]event // preallocated buffer in case we only log a few events
 }
 
 func (tr *trace) reset() {
@@ -711,11 +715,15 @@ func (tr *trace) reset() {
 	tr.traceID = 0
 	tr.spanID = 0
 	tr.IsError = false
+	tr.maxEvents = 0
 	tr.events = nil
 	tr.refs = 0
 	tr.recycler = nil
 	tr.disc = 0
 	tr.finishStack = nil
+	for i := range tr.eventsBuf {
+		tr.eventsBuf[i] = event{}
+	}
 }
 
 // delta returns the elapsed time since the last event or the trace start,
@@ -744,7 +752,7 @@ func (tr *trace) addEvent(x interface{}, recyclable, sensitive bool) {
 		and very unlikely to be the fault of this code.
 
 		The most likely scenario is that some code elsewhere is using
-		a requestz.Trace after its Finish method is called.
+		a trace.Trace after its Finish method is called.
 		You can temporarily set the DebugUseAfterFinish var
 		to help discover where that is; do not leave that var set,
 		since it makes this package much less efficient.
@@ -753,11 +761,11 @@ func (tr *trace) addEvent(x interface{}, recyclable, sensitive bool) {
 	e := event{When: time.Now(), What: x, Recyclable: recyclable, Sensitive: sensitive}
 	tr.mu.Lock()
 	e.Elapsed, e.NewDay = tr.delta(e.When)
-	if len(tr.events) < cap(tr.events) {
+	if len(tr.events) < tr.maxEvents {
 		tr.events = append(tr.events, e)
 	} else {
 		// Discard the middle events.
-		di := int((cap(tr.events) - 1) / 2)
+		di := int((tr.maxEvents - 1) / 2)
 		if d, ok := tr.events[di].What.(*discarded); ok {
 			(*d)++
 		} else {
@@ -777,7 +785,7 @@ func (tr *trace) addEvent(x interface{}, recyclable, sensitive bool) {
 			go tr.recycler(tr.events[di+1].What)
 		}
 		copy(tr.events[di+1:], tr.events[di+2:])
-		tr.events[cap(tr.events)-1] = e
+		tr.events[tr.maxEvents-1] = e
 	}
 	tr.mu.Unlock()
 }
@@ -803,7 +811,7 @@ func (tr *trace) SetTraceInfo(traceID, spanID uint64) {
 func (tr *trace) SetMaxEvents(m int) {
 	// Always keep at least three events: first, discarded count, last.
 	if len(tr.events) == 0 && m > 3 {
-		tr.events = make([]event, 0, m)
+		tr.maxEvents = m
 	}
 }
 
@@ -894,10 +902,18 @@ func elapsed(d time.Duration) string {
 	return string(b)
 }
 
-var pageTmpl = template.Must(template.New("Page").Funcs(template.FuncMap{
-	"elapsed": elapsed,
-	"add":     func(a, b int) int { return a + b },
-}).Parse(pageHTML))
+var pageTmplCache *template.Template
+var pageTmplOnce sync.Once
+
+func pageTmpl() *template.Template {
+	pageTmplOnce.Do(func() {
+		pageTmplCache = template.Must(template.New("Page").Funcs(template.FuncMap{
+			"elapsed": elapsed,
+			"add":     func(a, b int) int { return a + b },
+		}).Parse(pageHTML))
+	})
+	return pageTmplCache
+}
 
 const pageHTML = `
 {{template "Prolog" .}}

vendor/golang.org/x/text/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2009 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/golang.org/x/text/PATENTS

@@ -0,0 +1,22 @@
+Additional IP Rights Grant (Patents)
+
+"This implementation" means the copyrightable works distributed by
+Google as part of the Go project.
+
+Google hereby grants to You a perpetual, worldwide, non-exclusive,
+no-charge, royalty-free, irrevocable (except as stated in this section)
+patent license to make, have made, use, offer to sell, sell, import,
+transfer and otherwise run, modify and propagate the contents of this
+implementation of Go, where such license applies only to those patent
+claims, both currently owned or controlled by Google and acquired in
+the future, licensable by Google that are necessarily infringed by this
+implementation of Go.  This grant does not include claims that would be
+infringed only as a consequence of further modification of this
+implementation.  If you or your agent or exclusive licensee institute or
+order or agree to the institution of patent litigation against any
+entity (including a cross-claim or counterclaim in a lawsuit) alleging
+that this implementation of Go or any code incorporated within this
+implementation of Go constitutes direct or contributory patent
+infringement, or inducement of patent infringement, then any patent
+rights granted to you under this License for this implementation of Go
+shall terminate as of the date such litigation is filed.

vendor/golang.org/x/text/doc.go

@@ -0,0 +1,13 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:generate go run gen.go
+
+// text is a repository of text-related packages related to internationalization
+// (i18n) and localization (l10n), such as character encodings, text
+// transformations, and locale-specific text handling.
+package text
+
+// TODO: more documentation on general concepts, such as Transformers, use
+// of normalization, etc.

vendor/golang.org/x/text/gen.go

@@ -0,0 +1,291 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+
+// gen runs go generate on Unicode- and CLDR-related package in the text
+// repositories, taking into account dependencies and versions.
+package main
+
+import (
+	"bytes"
+	"flag"
+	"fmt"
+	"go/build"
+	"go/format"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path"
+	"path/filepath"
+	"regexp"
+	"runtime"
+	"strings"
+	"sync"
+	"unicode"
+
+	"golang.org/x/text/internal/gen"
+)
+
+var (
+	verbose     = flag.Bool("v", false, "verbose output")
+	force       = flag.Bool("force", false, "ignore failing dependencies")
+	doCore      = flag.Bool("core", false, "force an update to core")
+	excludeList = flag.String("exclude", "",
+		"comma-separated list of packages to exclude")
+
+	// The user can specify a selection of packages to build on the command line.
+	args []string
+)
+
+func exclude(pkg string) bool {
+	if len(args) > 0 {
+		return !contains(args, pkg)
+	}
+	return contains(strings.Split(*excludeList, ","), pkg)
+}
+
+// TODO:
+// - Better version handling.
+// - Generate tables for the core unicode package?
+// - Add generation for encodings. This requires some retooling here and there.
+// - Running repo-wide "long" tests.
+
+var vprintf = fmt.Printf
+
+func main() {
+	gen.Init()
+	args = flag.Args()
+	if !*verbose {
+		// Set vprintf to a no-op.
+		vprintf = func(string, ...interface{}) (int, error) { return 0, nil }
+	}
+
+	// TODO: create temporary cache directory to load files and create and set
+	// a "cache" option if the user did not specify the UNICODE_DIR environment
+	// variable. This will prevent duplicate downloads and also will enable long
+	// tests, which really need to be run after each generated package.
+
+	updateCore := *doCore
+	if gen.UnicodeVersion() != unicode.Version {
+		fmt.Printf("Requested Unicode version %s; core unicode version is %s.\n",
+			gen.UnicodeVersion(),
+			unicode.Version)
+		// TODO: use collate to compare. Simple comparison will work, though,
+		// until Unicode reaches version 10. To avoid circular dependencies, we
+		// could use the NumericWeighter without using package collate using a
+		// trivial Weighter implementation.
+		if gen.UnicodeVersion() < unicode.Version && !*force {
+			os.Exit(2)
+		}
+		updateCore = true
+	}
+
+	var unicode = &dependency{}
+	if updateCore {
+		fmt.Printf("Updating core to version %s...\n", gen.UnicodeVersion())
+		unicode = generate("unicode")
+
+		// Test some users of the unicode packages, especially the ones that
+		// keep a mirrored table. These may need to be corrected by hand.
+		generate("regexp", unicode)
+		generate("strconv", unicode) // mimics Unicode table
+		generate("strings", unicode)
+		generate("testing", unicode) // mimics Unicode table
+	}
+
+	var (
+		cldr       = generate("./unicode/cldr", unicode)
+		language   = generate("./language", cldr)
+		internal   = generate("./internal", unicode, language)
+		norm       = generate("./unicode/norm", unicode)
+		rangetable = generate("./unicode/rangetable", unicode)
+		cases      = generate("./cases", unicode, norm, language, rangetable)
+		width      = generate("./width", unicode)
+		bidi       = generate("./unicode/bidi", unicode, norm, rangetable)
+		mib        = generate("./encoding/internal/identifier", unicode)
+		_          = generate("./encoding/htmlindex", unicode, language, mib)
+		_          = generate("./encoding/ianaindex", unicode, language, mib)
+		_          = generate("./secure/precis", unicode, norm, rangetable, cases, width, bidi)
+		_          = generate("./currency", unicode, cldr, language, internal)
+		_          = generate("./internal/number", unicode, cldr, language, internal)
+		_          = generate("./internal/export/idna", unicode, bidi, norm)
+		_          = generate("./language/display", unicode, cldr, language, internal)
+		_          = generate("./collate", unicode, norm, cldr, language, rangetable)
+		_          = generate("./search", unicode, norm, cldr, language, rangetable)
+	)
+	all.Wait()
+
+	// Copy exported packages to the destination golang.org repo.
+	copyExported("golang.org/x/net/idna")
+
+	if updateCore {
+		copyVendored()
+	}
+
+	if hasErrors {
+		fmt.Println("FAIL")
+		os.Exit(1)
+	}
+	vprintf("SUCCESS\n")
+}
+
+var (
+	all       sync.WaitGroup
+	hasErrors bool
+)
+
+type dependency struct {
+	sync.WaitGroup
+	hasErrors bool
+}
+
+func generate(pkg string, deps ...*dependency) *dependency {
+	var wg dependency
+	if exclude(pkg) {
+		return &wg
+	}
+	wg.Add(1)
+	all.Add(1)
+	go func() {
+		defer wg.Done()
+		defer all.Done()
+		// Wait for dependencies to finish.
+		for _, d := range deps {
+			d.Wait()
+			if d.hasErrors && !*force {
+				fmt.Printf("--- ABORT: %s\n", pkg)
+				wg.hasErrors = true
+				return
+			}
+		}
+		vprintf("=== GENERATE %s\n", pkg)
+		args := []string{"generate"}
+		if *verbose {
+			args = append(args, "-v")
+		}
+		args = append(args, pkg)
+		cmd := exec.Command(filepath.Join(runtime.GOROOT(), "bin", "go"), args...)
+		w := &bytes.Buffer{}
+		cmd.Stderr = w
+		cmd.Stdout = w
+		if err := cmd.Run(); err != nil {
+			fmt.Printf("--- FAIL: %s:\n\t%v\n\tError: %v\n", pkg, indent(w), err)
+			hasErrors = true
+			wg.hasErrors = true
+			return
+		}
+
+		vprintf("=== TEST %s\n", pkg)
+		args[0] = "test"
+		cmd = exec.Command(filepath.Join(runtime.GOROOT(), "bin", "go"), args...)
+		wt := &bytes.Buffer{}
+		cmd.Stderr = wt
+		cmd.Stdout = wt
+		if err := cmd.Run(); err != nil {
+			fmt.Printf("--- FAIL: %s:\n\t%v\n\tError: %v\n", pkg, indent(wt), err)
+			hasErrors = true
+			wg.hasErrors = true
+			return
+		}
+		vprintf("--- SUCCESS: %s\n\t%v\n", pkg, indent(w))
+		fmt.Print(wt.String())
+	}()
+	return &wg
+}
+
+// copyExported copies a package in x/text/internal/export to the
+// destination repository.
+func copyExported(p string) {
+	copyPackage(
+		filepath.Join("internal", "export", path.Base(p)),
+		filepath.Join("..", filepath.FromSlash(p[len("golang.org/x"):])),
+		"golang.org/x/text/internal/export/"+path.Base(p),
+		p)
+}
+
+// copyVendored copies packages used by Go core into the vendored directory.
+func copyVendored() {
+	root := filepath.Join(build.Default.GOROOT, filepath.FromSlash("src/vendor/golang_org/x"))
+
+	err := filepath.Walk(root, func(dir string, info os.FileInfo, err error) error {
+		if err != nil || !info.IsDir() || root == dir {
+			return err
+		}
+		src := dir[len(root)+1:]
+		const slash = string(filepath.Separator)
+		if c := strings.Split(src, slash); c[0] == "text" {
+			// Copy a text repo package from its normal location.
+			src = strings.Join(c[1:], slash)
+		} else {
+			// Copy the vendored package if it exists in the export directory.
+			src = filepath.Join("internal", "export", filepath.Base(src))
+		}
+		copyPackage(src, dir, "golang.org", "golang_org")
+		return nil
+	})
+	if err != nil {
+		fmt.Printf("Seeding directory %s has failed %v:", root, err)
+		os.Exit(1)
+	}
+}
+
+// goGenRE is used to remove go:generate lines.
+var goGenRE = regexp.MustCompile("//go:generate[^\n]*\n")
+
+// copyPackage copies relevant files from a directory in x/text to the
+// destination package directory. The destination package is assumed to have
+// the same name. For each copied file go:generate lines are removed and
+// and package comments are rewritten to the new path.
+func copyPackage(dirSrc, dirDst, search, replace string) {
+	err := filepath.Walk(dirSrc, func(file string, info os.FileInfo, err error) error {
+		base := filepath.Base(file)
+		if err != nil || info.IsDir() ||
+			!strings.HasSuffix(base, ".go") ||
+			strings.HasSuffix(base, "_test.go") && !strings.HasPrefix(base, "example") ||
+			// Don't process subdirectories.
+			filepath.Dir(file) != dirSrc {
+			return nil
+		}
+		b, err := ioutil.ReadFile(file)
+		if err != nil || bytes.Contains(b, []byte("\n// +build ignore")) {
+			return err
+		}
+		// Fix paths.
+		b = bytes.Replace(b, []byte(search), []byte(replace), -1)
+		// Remove go:generate lines.
+		b = goGenRE.ReplaceAllLiteral(b, nil)
+		comment := "// Code generated by running \"go generate\" in golang.org/x/text. DO NOT EDIT.\n\n"
+		if *doCore {
+			comment = "// Code generated by running \"go run gen.go -core\" in golang.org/x/text. DO NOT EDIT.\n\n"
+		}
+		if !bytes.HasPrefix(b, []byte(comment)) {
+			b = append([]byte(comment), b...)
+		}
+		if b, err = format.Source(b); err != nil {
+			fmt.Println("Failed to format file:", err)
+			os.Exit(1)
+		}
+		file = filepath.Join(dirDst, base)
+		vprintf("=== COPY %s\n", file)
+		return ioutil.WriteFile(file, b, 0666)
+	})
+	if err != nil {
+		fmt.Println("Copying exported files failed:", err)
+		os.Exit(1)
+	}
+}
+
+func contains(a []string, s string) bool {
+	for _, e := range a {
+		if s == e {
+			return true
+		}
+	}
+	return false
+}
+
+func indent(b *bytes.Buffer) string {
+	return strings.Replace(strings.TrimSpace(b.String()), "\n", "\n\t", -1)
+}

vendor/golang.org/x/text/secure/bidirule/bidirule.go

@@ -0,0 +1,342 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package bidirule implements the Bidi Rule defined by RFC 5893.
+//
+// This package is under development. The API may change without notice and
+// without preserving backward compatibility.
+package bidirule
+
+import (
+	"errors"
+	"unicode/utf8"
+
+	"golang.org/x/text/transform"
+	"golang.org/x/text/unicode/bidi"
+)
+
+// This file contains an implementation of RFC 5893: Right-to-Left Scripts for
+// Internationalized Domain Names for Applications (IDNA)
+//
+// A label is an individual component of a domain name.  Labels are usually
+// shown separated by dots; for example, the domain name "www.example.com" is
+// composed of three labels: "www", "example", and "com".
+//
+// An RTL label is a label that contains at least one character of class R, AL,
+// or AN. An LTR label is any label that is not an RTL label.
+//
+// A "Bidi domain name" is a domain name that contains at least one RTL label.
+//
+//  The following guarantees can be made based on the above:
+//
+//  o  In a domain name consisting of only labels that satisfy the rule,
+//     the requirements of Section 3 are satisfied.  Note that even LTR
+//     labels and pure ASCII labels have to be tested.
+//
+//  o  In a domain name consisting of only LDH labels (as defined in the
+//     Definitions document [RFC5890]) and labels that satisfy the rule,
+//     the requirements of Section 3 are satisfied as long as a label
+//     that starts with an ASCII digit does not come after a
+//     right-to-left label.
+//
+//  No guarantee is given for other combinations.
+
+// ErrInvalid indicates a label is invalid according to the Bidi Rule.
+var ErrInvalid = errors.New("bidirule: failed Bidi Rule")
+
+type ruleState uint8
+
+const (
+	ruleInitial ruleState = iota
+	ruleLTR
+	ruleLTRFinal
+	ruleRTL
+	ruleRTLFinal
+	ruleInvalid
+)
+
+type ruleTransition struct {
+	next ruleState
+	mask uint16
+}
+
+var transitions = [...][2]ruleTransition{
+	// [2.1] The first character must be a character with Bidi property L, R, or
+	// AL. If it has the R or AL property, it is an RTL label; if it has the L
+	// property, it is an LTR label.
+	ruleInitial: {
+		{ruleLTRFinal, 1 << bidi.L},
+		{ruleRTLFinal, 1<<bidi.R | 1<<bidi.AL},
+	},
+	ruleRTL: {
+		// [2.3] In an RTL label, the end of the label must be a character with
+		// Bidi property R, AL, EN, or AN, followed by zero or more characters
+		// with Bidi property NSM.
+		{ruleRTLFinal, 1<<bidi.R | 1<<bidi.AL | 1<<bidi.EN | 1<<bidi.AN},
+
+		// [2.2] In an RTL label, only characters with the Bidi properties R,
+		// AL, AN, EN, ES, CS, ET, ON, BN, or NSM are allowed.
+		// We exclude the entries from [2.3]
+		{ruleRTL, 1<<bidi.ES | 1<<bidi.CS | 1<<bidi.ET | 1<<bidi.ON | 1<<bidi.BN | 1<<bidi.NSM},
+	},
+	ruleRTLFinal: {
+		// [2.3] In an RTL label, the end of the label must be a character with
+		// Bidi property R, AL, EN, or AN, followed by zero or more characters
+		// with Bidi property NSM.
+		{ruleRTLFinal, 1<<bidi.R | 1<<bidi.AL | 1<<bidi.EN | 1<<bidi.AN | 1<<bidi.NSM},
+
+		// [2.2] In an RTL label, only characters with the Bidi properties R,
+		// AL, AN, EN, ES, CS, ET, ON, BN, or NSM are allowed.
+		// We exclude the entries from [2.3] and NSM.
+		{ruleRTL, 1<<bidi.ES | 1<<bidi.CS | 1<<bidi.ET | 1<<bidi.ON | 1<<bidi.BN},
+	},
+	ruleLTR: {
+		// [2.6] In an LTR label, the end of the label must be a character with
+		// Bidi property L or EN, followed by zero or more characters with Bidi
+		// property NSM.
+		{ruleLTRFinal, 1<<bidi.L | 1<<bidi.EN},
+
+		// [2.5] In an LTR label, only characters with the Bidi properties L,
+		// EN, ES, CS, ET, ON, BN, or NSM are allowed.
+		// We exclude the entries from [2.6].
+		{ruleLTR, 1<<bidi.ES | 1<<bidi.CS | 1<<bidi.ET | 1<<bidi.ON | 1<<bidi.BN | 1<<bidi.NSM},
+	},
+	ruleLTRFinal: {
+		// [2.6] In an LTR label, the end of the label must be a character with
+		// Bidi property L or EN, followed by zero or more characters with Bidi
+		// property NSM.
+		{ruleLTRFinal, 1<<bidi.L | 1<<bidi.EN | 1<<bidi.NSM},
+
+		// [2.5] In an LTR label, only characters with the Bidi properties L,
+		// EN, ES, CS, ET, ON, BN, or NSM are allowed.
+		// We exclude the entries from [2.6].
+		{ruleLTR, 1<<bidi.ES | 1<<bidi.CS | 1<<bidi.ET | 1<<bidi.ON | 1<<bidi.BN},
+	},
+	ruleInvalid: {
+		{ruleInvalid, 0},
+		{ruleInvalid, 0},
+	},
+}
+
+// [2.4] In an RTL label, if an EN is present, no AN may be present, and
+// vice versa.
+const exclusiveRTL = uint16(1<<bidi.EN | 1<<bidi.AN)
+
+// From RFC 5893
+// An RTL label is a label that contains at least one character of type
+// R, AL, or AN.
+//
+// An LTR label is any label that is not an RTL label.
+
+// Direction reports the direction of the given label as defined by RFC 5893.
+// The Bidi Rule does not have to be applied to labels of the category
+// LeftToRight.
+func Direction(b []byte) bidi.Direction {
+	for i := 0; i < len(b); {
+		e, sz := bidi.Lookup(b[i:])
+		if sz == 0 {
+			i++
+		}
+		c := e.Class()
+		if c == bidi.R || c == bidi.AL || c == bidi.AN {
+			return bidi.RightToLeft
+		}
+		i += sz
+	}
+	return bidi.LeftToRight
+}
+
+// DirectionString reports the direction of the given label as defined by RFC
+// 5893. The Bidi Rule does not have to be applied to labels of the category
+// LeftToRight.
+func DirectionString(s string) bidi.Direction {
+	for i := 0; i < len(s); {
+		e, sz := bidi.LookupString(s[i:])
+		if sz == 0 {
+			i++
+		}
+		c := e.Class()
+		if c == bidi.R || c == bidi.AL || c == bidi.AN {
+			return bidi.RightToLeft
+		}
+		i += sz
+	}
+	return bidi.LeftToRight
+}
+
+// Valid reports whether b conforms to the BiDi rule.
+func Valid(b []byte) bool {
+	var t Transformer
+	if n, ok := t.advance(b); !ok || n < len(b) {
+		return false
+	}
+	return t.isFinal()
+}
+
+// ValidString reports whether s conforms to the BiDi rule.
+func ValidString(s string) bool {
+	var t Transformer
+	if n, ok := t.advanceString(s); !ok || n < len(s) {
+		return false
+	}
+	return t.isFinal()
+}
+
+// New returns a Transformer that verifies that input adheres to the Bidi Rule.
+func New() *Transformer {
+	return &Transformer{}
+}
+
+// Transformer implements transform.Transform.
+type Transformer struct {
+	state  ruleState
+	hasRTL bool
+	seen   uint16
+}
+
+// A rule can only be violated for "Bidi Domain names", meaning if one of the
+// following categories has been observed.
+func (t *Transformer) isRTL() bool {
+	const isRTL = 1<<bidi.R | 1<<bidi.AL | 1<<bidi.AN
+	return t.seen&isRTL != 0
+}
+
+func (t *Transformer) isFinal() bool {
+	if !t.isRTL() {
+		return true
+	}
+	return t.state == ruleLTRFinal || t.state == ruleRTLFinal || t.state == ruleInitial
+}
+
+// Reset implements transform.Transformer.
+func (t *Transformer) Reset() { *t = Transformer{} }
+
+// Transform implements transform.Transformer. This Transformer has state and
+// needs to be reset between uses.
+func (t *Transformer) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
+	if len(dst) < len(src) {
+		src = src[:len(dst)]
+		atEOF = false
+		err = transform.ErrShortDst
+	}
+	n, err1 := t.Span(src, atEOF)
+	copy(dst, src[:n])
+	if err == nil || err1 != nil && err1 != transform.ErrShortSrc {
+		err = err1
+	}
+	return n, n, err
+}
+
+// Span returns the first n bytes of src that conform to the Bidi rule.
+func (t *Transformer) Span(src []byte, atEOF bool) (n int, err error) {
+	if t.state == ruleInvalid && t.isRTL() {
+		return 0, ErrInvalid
+	}
+	n, ok := t.advance(src)
+	switch {
+	case !ok:
+		err = ErrInvalid
+	case n < len(src):
+		if !atEOF {
+			err = transform.ErrShortSrc
+			break
+		}
+		err = ErrInvalid
+	case !t.isFinal():
+		err = ErrInvalid
+	}
+	return n, err
+}
+
+// Precomputing the ASCII values decreases running time for the ASCII fast path
+// by about 30%.
+var asciiTable [128]bidi.Properties
+
+func init() {
+	for i := range asciiTable {
+		p, _ := bidi.LookupRune(rune(i))
+		asciiTable[i] = p
+	}
+}
+
+func (t *Transformer) advance(s []byte) (n int, ok bool) {
+	var e bidi.Properties
+	var sz int
+	for n < len(s) {
+		if s[n] < utf8.RuneSelf {
+			e, sz = asciiTable[s[n]], 1
+		} else {
+			e, sz = bidi.Lookup(s[n:])
+			if sz <= 1 {
+				if sz == 1 {
+					// We always consider invalid UTF-8 to be invalid, even if
+					// the string has not yet been determined to be RTL.
+					// TODO: is this correct?
+					return n, false
+				}
+				return n, true // incomplete UTF-8 encoding
+			}
+		}
+		// TODO: using CompactClass would result in noticeable speedup.
+		// See unicode/bidi/prop.go:Properties.CompactClass.
+		c := uint16(1 << e.Class())
+		t.seen |= c
+		if t.seen&exclusiveRTL == exclusiveRTL {
+			t.state = ruleInvalid
+			return n, false
+		}
+		switch tr := transitions[t.state]; {
+		case tr[0].mask&c != 0:
+			t.state = tr[0].next
+		case tr[1].mask&c != 0:
+			t.state = tr[1].next
+		default:
+			t.state = ruleInvalid
+			if t.isRTL() {
+				return n, false
+			}
+		}
+		n += sz
+	}
+	return n, true
+}
+
+func (t *Transformer) advanceString(s string) (n int, ok bool) {
+	var e bidi.Properties
+	var sz int
+	for n < len(s) {
+		if s[n] < utf8.RuneSelf {
+			e, sz = asciiTable[s[n]], 1
+		} else {
+			e, sz = bidi.LookupString(s[n:])
+			if sz <= 1 {
+				if sz == 1 {
+					return n, false // invalid UTF-8
+				}
+				return n, true // incomplete UTF-8 encoding
+			}
+		}
+		// TODO: using CompactClass results in noticeable speedup.
+		// See unicode/bidi/prop.go:Properties.CompactClass.
+		c := uint16(1 << e.Class())
+		t.seen |= c
+		if t.seen&exclusiveRTL == exclusiveRTL {
+			t.state = ruleInvalid
+			return n, false
+		}
+		switch tr := transitions[t.state]; {
+		case tr[0].mask&c != 0:
+			t.state = tr[0].next
+		case tr[1].mask&c != 0:
+			t.state = tr[1].next
+		default:
+			t.state = ruleInvalid
+			if t.isRTL() {
+				return n, false
+			}
+		}
+		n += sz
+	}
+	return n, true
+}

vendor/golang.org/x/text/transform/transform.go

@@ -0,0 +1,705 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package transform provides reader and writer wrappers that transform the
+// bytes passing through as well as various transformations. Example
+// transformations provided by other packages include normalization and
+// conversion between character sets.
+package transform // import "golang.org/x/text/transform"
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"unicode/utf8"
+)
+
+var (
+	// ErrShortDst means that the destination buffer was too short to
+	// receive all of the transformed bytes.
+	ErrShortDst = errors.New("transform: short destination buffer")
+
+	// ErrShortSrc means that the source buffer has insufficient data to
+	// complete the transformation.
+	ErrShortSrc = errors.New("transform: short source buffer")
+
+	// ErrEndOfSpan means that the input and output (the transformed input)
+	// are not identical.
+	ErrEndOfSpan = errors.New("transform: input and output are not identical")
+
+	// errInconsistentByteCount means that Transform returned success (nil
+	// error) but also returned nSrc inconsistent with the src argument.
+	errInconsistentByteCount = errors.New("transform: inconsistent byte count returned")
+
+	// errShortInternal means that an internal buffer is not large enough
+	// to make progress and the Transform operation must be aborted.
+	errShortInternal = errors.New("transform: short internal buffer")
+)
+
+// Transformer transforms bytes.
+type Transformer interface {
+	// Transform writes to dst the transformed bytes read from src, and
+	// returns the number of dst bytes written and src bytes read. The
+	// atEOF argument tells whether src represents the last bytes of the
+	// input.
+	//
+	// Callers should always process the nDst bytes produced and account
+	// for the nSrc bytes consumed before considering the error err.
+	//
+	// A nil error means that all of the transformed bytes (whether freshly
+	// transformed from src or left over from previous Transform calls)
+	// were written to dst. A nil error can be returned regardless of
+	// whether atEOF is true. If err is nil then nSrc must equal len(src);
+	// the converse is not necessarily true.
+	//
+	// ErrShortDst means that dst was too short to receive all of the
+	// transformed bytes. ErrShortSrc means that src had insufficient data
+	// to complete the transformation. If both conditions apply, then
+	// either error may be returned. Other than the error conditions listed
+	// here, implementations are free to report other errors that arise.
+	Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error)
+
+	// Reset resets the state and allows a Transformer to be reused.
+	Reset()
+}
+
+// SpanningTransformer extends the Transformer interface with a Span method
+// that determines how much of the input already conforms to the Transformer.
+type SpanningTransformer interface {
+	Transformer
+
+	// Span returns a position in src such that transforming src[:n] results in
+	// identical output src[:n] for these bytes. It does not necessarily return
+	// the largest such n. The atEOF argument tells whether src represents the
+	// last bytes of the input.
+	//
+	// Callers should always account for the n bytes consumed before
+	// considering the error err.
+	//
+	// A nil error means that all input bytes are known to be identical to the
+	// output produced by the Transformer. A nil error can be be returned
+	// regardless of whether atEOF is true. If err is nil, then then n must
+	// equal len(src); the converse is not necessarily true.
+	//
+	// ErrEndOfSpan means that the Transformer output may differ from the
+	// input after n bytes. Note that n may be len(src), meaning that the output
+	// would contain additional bytes after otherwise identical output.
+	// ErrShortSrc means that src had insufficient data to determine whether the
+	// remaining bytes would change. Other than the error conditions listed
+	// here, implementations are free to report other errors that arise.
+	//
+	// Calling Span can modify the Transformer state as a side effect. In
+	// effect, it does the transformation just as calling Transform would, only
+	// without copying to a destination buffer and only up to a point it can
+	// determine the input and output bytes are the same. This is obviously more
+	// limited than calling Transform, but can be more efficient in terms of
+	// copying and allocating buffers. Calls to Span and Transform may be
+	// interleaved.
+	Span(src []byte, atEOF bool) (n int, err error)
+}
+
+// NopResetter can be embedded by implementations of Transformer to add a nop
+// Reset method.
+type NopResetter struct{}
+
+// Reset implements the Reset method of the Transformer interface.
+func (NopResetter) Reset() {}
+
+// Reader wraps another io.Reader by transforming the bytes read.
+type Reader struct {
+	r   io.Reader
+	t   Transformer
+	err error
+
+	// dst[dst0:dst1] contains bytes that have been transformed by t but
+	// not yet copied out via Read.
+	dst        []byte
+	dst0, dst1 int
+
+	// src[src0:src1] contains bytes that have been read from r but not
+	// yet transformed through t.
+	src        []byte
+	src0, src1 int
+
+	// transformComplete is whether the transformation is complete,
+	// regardless of whether or not it was successful.
+	transformComplete bool
+}
+
+const defaultBufSize = 4096
+
+// NewReader returns a new Reader that wraps r by transforming the bytes read
+// via t. It calls Reset on t.
+func NewReader(r io.Reader, t Transformer) *Reader {
+	t.Reset()
+	return &Reader{
+		r:   r,
+		t:   t,
+		dst: make([]byte, defaultBufSize),
+		src: make([]byte, defaultBufSize),
+	}
+}
+
+// Read implements the io.Reader interface.
+func (r *Reader) Read(p []byte) (int, error) {
+	n, err := 0, error(nil)
+	for {
+		// Copy out any transformed bytes and return the final error if we are done.
+		if r.dst0 != r.dst1 {
+			n = copy(p, r.dst[r.dst0:r.dst1])
+			r.dst0 += n
+			if r.dst0 == r.dst1 && r.transformComplete {
+				return n, r.err
+			}
+			return n, nil
+		} else if r.transformComplete {
+			return 0, r.err
+		}
+
+		// Try to transform some source bytes, or to flush the transformer if we
+		// are out of source bytes. We do this even if r.r.Read returned an error.
+		// As the io.Reader documentation says, "process the n > 0 bytes returned
+		// before considering the error".
+		if r.src0 != r.src1 || r.err != nil {
+			r.dst0 = 0
+			r.dst1, n, err = r.t.Transform(r.dst, r.src[r.src0:r.src1], r.err == io.EOF)
+			r.src0 += n
+
+			switch {
+			case err == nil:
+				if r.src0 != r.src1 {
+					r.err = errInconsistentByteCount
+				}
+				// The Transform call was successful; we are complete if we
+				// cannot read more bytes into src.
+				r.transformComplete = r.err != nil
+				continue
+			case err == ErrShortDst && (r.dst1 != 0 || n != 0):
+				// Make room in dst by copying out, and try again.
+				continue
+			case err == ErrShortSrc && r.src1-r.src0 != len(r.src) && r.err == nil:
+				// Read more bytes into src via the code below, and try again.
+			default:
+				r.transformComplete = true
+				// The reader error (r.err) takes precedence over the
+				// transformer error (err) unless r.err is nil or io.EOF.
+				if r.err == nil || r.err == io.EOF {
+					r.err = err
+				}
+				continue
+			}
+		}
+
+		// Move any untransformed source bytes to the start of the buffer
+		// and read more bytes.
+		if r.src0 != 0 {
+			r.src0, r.src1 = 0, copy(r.src, r.src[r.src0:r.src1])
+		}
+		n, r.err = r.r.Read(r.src[r.src1:])
+		r.src1 += n
+	}
+}
+
+// TODO: implement ReadByte (and ReadRune??).
+
+// Writer wraps another io.Writer by transforming the bytes read.
+// The user needs to call Close to flush unwritten bytes that may
+// be buffered.
+type Writer struct {
+	w   io.Writer
+	t   Transformer
+	dst []byte
+
+	// src[:n] contains bytes that have not yet passed through t.
+	src []byte
+	n   int
+}
+
+// NewWriter returns a new Writer that wraps w by transforming the bytes written
+// via t. It calls Reset on t.
+func NewWriter(w io.Writer, t Transformer) *Writer {
+	t.Reset()
+	return &Writer{
+		w:   w,
+		t:   t,
+		dst: make([]byte, defaultBufSize),
+		src: make([]byte, defaultBufSize),
+	}
+}
+
+// Write implements the io.Writer interface. If there are not enough
+// bytes available to complete a Transform, the bytes will be buffered
+// for the next write. Call Close to convert the remaining bytes.
+func (w *Writer) Write(data []byte) (n int, err error) {
+	src := data
+	if w.n > 0 {
+		// Append bytes from data to the last remainder.
+		// TODO: limit the amount copied on first try.
+		n = copy(w.src[w.n:], data)
+		w.n += n
+		src = w.src[:w.n]
+	}
+	for {
+		nDst, nSrc, err := w.t.Transform(w.dst, src, false)
+		if _, werr := w.w.Write(w.dst[:nDst]); werr != nil {
+			return n, werr
+		}
+		src = src[nSrc:]
+		if w.n == 0 {
+			n += nSrc
+		} else if len(src) <= n {
+			// Enough bytes from w.src have been consumed. We make src point
+			// to data instead to reduce the copying.
+			w.n = 0
+			n -= len(src)
+			src = data[n:]
+			if n < len(data) && (err == nil || err == ErrShortSrc) {
+				continue
+			}
+		}
+		switch err {
+		case ErrShortDst:
+			// This error is okay as long as we are making progress.
+			if nDst > 0 || nSrc > 0 {
+				continue
+			}
+		case ErrShortSrc:
+			if len(src) < len(w.src) {
+				m := copy(w.src, src)
+				// If w.n > 0, bytes from data were already copied to w.src and n
+				// was already set to the number of bytes consumed.
+				if w.n == 0 {
+					n += m
+				}
+				w.n = m
+				err = nil
+			} else if nDst > 0 || nSrc > 0 {
+				// Not enough buffer to store the remainder. Keep processing as
+				// long as there is progress. Without this case, transforms that
+				// require a lookahead larger than the buffer may result in an
+				// error. This is not something one may expect to be common in
+				// practice, but it may occur when buffers are set to small
+				// sizes during testing.
+				continue
+			}
+		case nil:
+			if w.n > 0 {
+				err = errInconsistentByteCount
+			}
+		}
+		return n, err
+	}
+}
+
+// Close implements the io.Closer interface.
+func (w *Writer) Close() error {
+	src := w.src[:w.n]
+	for {
+		nDst, nSrc, err := w.t.Transform(w.dst, src, true)
+		if _, werr := w.w.Write(w.dst[:nDst]); werr != nil {
+			return werr
+		}
+		if err != ErrShortDst {
+			return err
+		}
+		src = src[nSrc:]
+	}
+}
+
+type nop struct{ NopResetter }
+
+func (nop) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
+	n := copy(dst, src)
+	if n < len(src) {
+		err = ErrShortDst
+	}
+	return n, n, err
+}
+
+func (nop) Span(src []byte, atEOF bool) (n int, err error) {
+	return len(src), nil
+}
+
+type discard struct{ NopResetter }
+
+func (discard) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
+	return 0, len(src), nil
+}
+
+var (
+	// Discard is a Transformer for which all Transform calls succeed
+	// by consuming all bytes and writing nothing.
+	Discard Transformer = discard{}
+
+	// Nop is a SpanningTransformer that copies src to dst.
+	Nop SpanningTransformer = nop{}
+)
+
+// chain is a sequence of links. A chain with N Transformers has N+1 links and
+// N+1 buffers. Of those N+1 buffers, the first and last are the src and dst
+// buffers given to chain.Transform and the middle N-1 buffers are intermediate
+// buffers owned by the chain. The i'th link transforms bytes from the i'th
+// buffer chain.link[i].b at read offset chain.link[i].p to the i+1'th buffer
+// chain.link[i+1].b at write offset chain.link[i+1].n, for i in [0, N).
+type chain struct {
+	link []link
+	err  error
+	// errStart is the index at which the error occurred plus 1. Processing
+	// errStart at this level at the next call to Transform. As long as
+	// errStart > 0, chain will not consume any more source bytes.
+	errStart int
+}
+
+func (c *chain) fatalError(errIndex int, err error) {
+	if i := errIndex + 1; i > c.errStart {
+		c.errStart = i
+		c.err = err
+	}
+}
+
+type link struct {
+	t Transformer
+	// b[p:n] holds the bytes to be transformed by t.
+	b []byte
+	p int
+	n int
+}
+
+func (l *link) src() []byte {
+	return l.b[l.p:l.n]
+}
+
+func (l *link) dst() []byte {
+	return l.b[l.n:]
+}
+
+// Chain returns a Transformer that applies t in sequence.
+func Chain(t ...Transformer) Transformer {
+	if len(t) == 0 {
+		return nop{}
+	}
+	c := &chain{link: make([]link, len(t)+1)}
+	for i, tt := range t {
+		c.link[i].t = tt
+	}
+	// Allocate intermediate buffers.
+	b := make([][defaultBufSize]byte, len(t)-1)
+	for i := range b {
+		c.link[i+1].b = b[i][:]
+	}
+	return c
+}
+
+// Reset resets the state of Chain. It calls Reset on all the Transformers.
+func (c *chain) Reset() {
+	for i, l := range c.link {
+		if l.t != nil {
+			l.t.Reset()
+		}
+		c.link[i].p, c.link[i].n = 0, 0
+	}
+}
+
+// TODO: make chain use Span (is going to be fun to implement!)
+
+// Transform applies the transformers of c in sequence.
+func (c *chain) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
+	// Set up src and dst in the chain.
+	srcL := &c.link[0]
+	dstL := &c.link[len(c.link)-1]
+	srcL.b, srcL.p, srcL.n = src, 0, len(src)
+	dstL.b, dstL.n = dst, 0
+	var lastFull, needProgress bool // for detecting progress
+
+	// i is the index of the next Transformer to apply, for i in [low, high].
+	// low is the lowest index for which c.link[low] may still produce bytes.
+	// high is the highest index for which c.link[high] has a Transformer.
+	// The error returned by Transform determines whether to increase or
+	// decrease i. We try to completely fill a buffer before converting it.
+	for low, i, high := c.errStart, c.errStart, len(c.link)-2; low <= i && i <= high; {
+		in, out := &c.link[i], &c.link[i+1]
+		nDst, nSrc, err0 := in.t.Transform(out.dst(), in.src(), atEOF && low == i)
+		out.n += nDst
+		in.p += nSrc
+		if i > 0 && in.p == in.n {
+			in.p, in.n = 0, 0
+		}
+		needProgress, lastFull = lastFull, false
+		switch err0 {
+		case ErrShortDst:
+			// Process the destination buffer next. Return if we are already
+			// at the high index.
+			if i == high {
+				return dstL.n, srcL.p, ErrShortDst
+			}
+			if out.n != 0 {
+				i++
+				// If the Transformer at the next index is not able to process any
+				// source bytes there is nothing that can be done to make progress
+				// and the bytes will remain unprocessed. lastFull is used to
+				// detect this and break out of the loop with a fatal error.
+				lastFull = true
+				continue
+			}
+			// The destination buffer was too small, but is completely empty.
+			// Return a fatal error as this transformation can never complete.
+			c.fatalError(i, errShortInternal)
+		case ErrShortSrc:
+			if i == 0 {
+				// Save ErrShortSrc in err. All other errors take precedence.
+				err = ErrShortSrc
+				break
+			}
+			// Source bytes were depleted before filling up the destination buffer.
+			// Verify we made some progress, move the remaining bytes to the errStart
+			// and try to get more source bytes.
+			if needProgress && nSrc == 0 || in.n-in.p == len(in.b) {
+				// There were not enough source bytes to proceed while the source
+				// buffer cannot hold any more bytes. Return a fatal error as this
+				// transformation can never complete.
+				c.fatalError(i, errShortInternal)
+				break
+			}
+			// in.b is an internal buffer and we can make progress.
+			in.p, in.n = 0, copy(in.b, in.src())
+			fallthrough
+		case nil:
+			// if i == low, we have depleted the bytes at index i or any lower levels.
+			// In that case we increase low and i. In all other cases we decrease i to
+			// fetch more bytes before proceeding to the next index.
+			if i > low {
+				i--
+				continue
+			}
+		default:
+			c.fatalError(i, err0)
+		}
+		// Exhausted level low or fatal error: increase low and continue
+		// to process the bytes accepted so far.
+		i++
+		low = i
+	}
+
+	// If c.errStart > 0, this means we found a fatal error.  We will clear
+	// all upstream buffers. At this point, no more progress can be made
+	// downstream, as Transform would have bailed while handling ErrShortDst.
+	if c.errStart > 0 {
+		for i := 1; i < c.errStart; i++ {
+			c.link[i].p, c.link[i].n = 0, 0
+		}
+		err, c.errStart, c.err = c.err, 0, nil
+	}
+	return dstL.n, srcL.p, err
+}
+
+// Deprecated: use runes.Remove instead.
+func RemoveFunc(f func(r rune) bool) Transformer {
+	return removeF(f)
+}
+
+type removeF func(r rune) bool
+
+func (removeF) Reset() {}
+
+// Transform implements the Transformer interface.
+func (t removeF) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
+	for r, sz := rune(0), 0; len(src) > 0; src = src[sz:] {
+
+		if r = rune(src[0]); r < utf8.RuneSelf {
+			sz = 1
+		} else {
+			r, sz = utf8.DecodeRune(src)
+
+			if sz == 1 {
+				// Invalid rune.
+				if !atEOF && !utf8.FullRune(src) {
+					err = ErrShortSrc
+					break
+				}
+				// We replace illegal bytes with RuneError. Not doing so might
+				// otherwise turn a sequence of invalid UTF-8 into valid UTF-8.
+				// The resulting byte sequence may subsequently contain runes
+				// for which t(r) is true that were passed unnoticed.
+				if !t(r) {
+					if nDst+3 > len(dst) {
+						err = ErrShortDst
+						break
+					}
+					nDst += copy(dst[nDst:], "\uFFFD")
+				}
+				nSrc++
+				continue
+			}
+		}
+
+		if !t(r) {
+			if nDst+sz > len(dst) {
+				err = ErrShortDst
+				break
+			}
+			nDst += copy(dst[nDst:], src[:sz])
+		}
+		nSrc += sz
+	}
+	return
+}
+
+// grow returns a new []byte that is longer than b, and copies the first n bytes
+// of b to the start of the new slice.
+func grow(b []byte, n int) []byte {
+	m := len(b)
+	if m <= 32 {
+		m = 64
+	} else if m <= 256 {
+		m *= 2
+	} else {
+		m += m >> 1
+	}
+	buf := make([]byte, m)
+	copy(buf, b[:n])
+	return buf
+}
+
+const initialBufSize = 128
+
+// String returns a string with the result of converting s[:n] using t, where
+// n <= len(s). If err == nil, n will be len(s). It calls Reset on t.
+func String(t Transformer, s string) (result string, n int, err error) {
+	t.Reset()
+	if s == "" {
+		// Fast path for the common case for empty input. Results in about a
+		// 86% reduction of running time for BenchmarkStringLowerEmpty.
+		if _, _, err := t.Transform(nil, nil, true); err == nil {
+			return "", 0, nil
+		}
+	}
+
+	// Allocate only once. Note that both dst and src escape when passed to
+	// Transform.
+	buf := [2 * initialBufSize]byte{}
+	dst := buf[:initialBufSize:initialBufSize]
+	src := buf[initialBufSize : 2*initialBufSize]
+
+	// The input string s is transformed in multiple chunks (starting with a
+	// chunk size of initialBufSize). nDst and nSrc are per-chunk (or
+	// per-Transform-call) indexes, pDst and pSrc are overall indexes.
+	nDst, nSrc := 0, 0
+	pDst, pSrc := 0, 0
+
+	// pPrefix is the length of a common prefix: the first pPrefix bytes of the
+	// result will equal the first pPrefix bytes of s. It is not guaranteed to
+	// be the largest such value, but if pPrefix, len(result) and len(s) are
+	// all equal after the final transform (i.e. calling Transform with atEOF
+	// being true returned nil error) then we don't need to allocate a new
+	// result string.
+	pPrefix := 0
+	for {
+		// Invariant: pDst == pPrefix && pSrc == pPrefix.
+
+		n := copy(src, s[pSrc:])
+		nDst, nSrc, err = t.Transform(dst, src[:n], pSrc+n == len(s))
+		pDst += nDst
+		pSrc += nSrc
+
+		// TODO:  let transformers implement an optional Spanner interface, akin
+		// to norm's QuickSpan. This would even allow us to avoid any allocation.
+		if !bytes.Equal(dst[:nDst], src[:nSrc]) {
+			break
+		}
+		pPrefix = pSrc
+		if err == ErrShortDst {
+			// A buffer can only be short if a transformer modifies its input.
+			break
+		} else if err == ErrShortSrc {
+			if nSrc == 0 {
+				// No progress was made.
+				break
+			}
+			// Equal so far and !atEOF, so continue checking.
+		} else if err != nil || pPrefix == len(s) {
+			return string(s[:pPrefix]), pPrefix, err
+		}
+	}
+	// Post-condition: pDst == pPrefix + nDst && pSrc == pPrefix + nSrc.
+
+	// We have transformed the first pSrc bytes of the input s to become pDst
+	// transformed bytes. Those transformed bytes are discontiguous: the first
+	// pPrefix of them equal s[:pPrefix] and the last nDst of them equal
+	// dst[:nDst]. We copy them around, into a new dst buffer if necessary, so
+	// that they become one contiguous slice: dst[:pDst].
+	if pPrefix != 0 {
+		newDst := dst
+		if pDst > len(newDst) {
+			newDst = make([]byte, len(s)+nDst-nSrc)
+		}
+		copy(newDst[pPrefix:pDst], dst[:nDst])
+		copy(newDst[:pPrefix], s[:pPrefix])
+		dst = newDst
+	}
+
+	// Prevent duplicate Transform calls with atEOF being true at the end of
+	// the input. Also return if we have an unrecoverable error.
+	if (err == nil && pSrc == len(s)) ||
+		(err != nil && err != ErrShortDst && err != ErrShortSrc) {
+		return string(dst[:pDst]), pSrc, err
+	}
+
+	// Transform the remaining input, growing dst and src buffers as necessary.
+	for {
+		n := copy(src, s[pSrc:])
+		nDst, nSrc, err := t.Transform(dst[pDst:], src[:n], pSrc+n == len(s))
+		pDst += nDst
+		pSrc += nSrc
+
+		// If we got ErrShortDst or ErrShortSrc, do not grow as long as we can
+		// make progress. This may avoid excessive allocations.
+		if err == ErrShortDst {
+			if nDst == 0 {
+				dst = grow(dst, pDst)
+			}
+		} else if err == ErrShortSrc {
+			if nSrc == 0 {
+				src = grow(src, 0)
+			}
+		} else if err != nil || pSrc == len(s) {
+			return string(dst[:pDst]), pSrc, err
+		}
+	}
+}
+
+// Bytes returns a new byte slice with the result of converting b[:n] using t,
+// where n <= len(b). If err == nil, n will be len(b). It calls Reset on t.
+func Bytes(t Transformer, b []byte) (result []byte, n int, err error) {
+	return doAppend(t, 0, make([]byte, len(b)), b)
+}
+
+// Append appends the result of converting src[:n] using t to dst, where
+// n <= len(src), If err == nil, n will be len(src). It calls Reset on t.
+func Append(t Transformer, dst, src []byte) (result []byte, n int, err error) {
+	if len(dst) == cap(dst) {
+		n := len(src) + len(dst) // It is okay for this to be 0.
+		b := make([]byte, n)
+		dst = b[:copy(b, dst)]
+	}
+	return doAppend(t, len(dst), dst[:cap(dst)], src)
+}
+
+func doAppend(t Transformer, pDst int, dst, src []byte) (result []byte, n int, err error) {
+	t.Reset()
+	pSrc := 0
+	for {
+		nDst, nSrc, err := t.Transform(dst[pDst:], src[pSrc:], true)
+		pDst += nDst
+		pSrc += nSrc
+		if err != ErrShortDst {
+			return dst[:pDst], pSrc, err
+		}
+
+		// Grow the destination buffer, but do not grow as long as we can make
+		// progress. This may avoid excessive allocations.
+		if nDst == 0 {
+			dst = grow(dst, pDst)
+		}
+	}
+}

vendor/golang.org/x/text/unicode/bidi/bidi.go

@@ -0,0 +1,198 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:generate go run gen.go gen_trieval.go gen_ranges.go
+
+// Package bidi contains functionality for bidirectional text support.
+//
+// See http://www.unicode.org/reports/tr9.
+//
+// NOTE: UNDER CONSTRUCTION. This API may change in backwards incompatible ways
+// and without notice.
+package bidi // import "golang.org/x/text/unicode/bidi"
+
+// TODO:
+// The following functionality would not be hard to implement, but hinges on
+// the definition of a Segmenter interface. For now this is up to the user.
+// - Iterate over paragraphs
+// - Segmenter to iterate over runs directly from a given text.
+// Also:
+// - Transformer for reordering?
+// - Transformer (validator, really) for Bidi Rule.
+
+// This API tries to avoid dealing with embedding levels for now. Under the hood
+// these will be computed, but the question is to which extent the user should
+// know they exist. We should at some point allow the user to specify an
+// embedding hierarchy, though.
+
+// A Direction indicates the overall flow of text.
+type Direction int
+
+const (
+	// LeftToRight indicates the text contains no right-to-left characters and
+	// that either there are some left-to-right characters or the option
+	// DefaultDirection(LeftToRight) was passed.
+	LeftToRight Direction = iota
+
+	// RightToLeft indicates the text contains no left-to-right characters and
+	// that either there are some right-to-left characters or the option
+	// DefaultDirection(RightToLeft) was passed.
+	RightToLeft
+
+	// Mixed indicates text contains both left-to-right and right-to-left
+	// characters.
+	Mixed
+
+	// Neutral means that text contains no left-to-right and right-to-left
+	// characters and that no default direction has been set.
+	Neutral
+)
+
+type options struct{}
+
+// An Option is an option for Bidi processing.
+type Option func(*options)
+
+// ICU allows the user to define embedding levels. This may be used, for example,
+// to use hierarchical structure of markup languages to define embeddings.
+// The following option may be a way to expose this functionality in this API.
+// // LevelFunc sets a function that associates nesting levels with the given text.
+// // The levels function will be called with monotonically increasing values for p.
+// func LevelFunc(levels func(p int) int) Option {
+// 	panic("unimplemented")
+// }
+
+// DefaultDirection sets the default direction for a Paragraph. The direction is
+// overridden if the text contains directional characters.
+func DefaultDirection(d Direction) Option {
+	panic("unimplemented")
+}
+
+// A Paragraph holds a single Paragraph for Bidi processing.
+type Paragraph struct {
+	// buffers
+}
+
+// SetBytes configures p for the given paragraph text. It replaces text
+// previously set by SetBytes or SetString. If b contains a paragraph separator
+// it will only process the first paragraph and report the number of bytes
+// consumed from b including this separator. Error may be non-nil if options are
+// given.
+func (p *Paragraph) SetBytes(b []byte, opts ...Option) (n int, err error) {
+	panic("unimplemented")
+}
+
+// SetString configures p for the given paragraph text. It replaces text
+// previously set by SetBytes or SetString. If b contains a paragraph separator
+// it will only process the first paragraph and report the number of bytes
+// consumed from b including this separator. Error may be non-nil if options are
+// given.
+func (p *Paragraph) SetString(s string, opts ...Option) (n int, err error) {
+	panic("unimplemented")
+}
+
+// IsLeftToRight reports whether the principle direction of rendering for this
+// paragraphs is left-to-right. If this returns false, the principle direction
+// of rendering is right-to-left.
+func (p *Paragraph) IsLeftToRight() bool {
+	panic("unimplemented")
+}
+
+// Direction returns the direction of the text of this paragraph.
+//
+// The direction may be LeftToRight, RightToLeft, Mixed, or Neutral.
+func (p *Paragraph) Direction() Direction {
+	panic("unimplemented")
+}
+
+// RunAt reports the Run at the given position of the input text.
+//
+// This method can be used for computing line breaks on paragraphs.
+func (p *Paragraph) RunAt(pos int) Run {
+	panic("unimplemented")
+}
+
+// Order computes the visual ordering of all the runs in a Paragraph.
+func (p *Paragraph) Order() (Ordering, error) {
+	panic("unimplemented")
+}
+
+// Line computes the visual ordering of runs for a single line starting and
+// ending at the given positions in the original text.
+func (p *Paragraph) Line(start, end int) (Ordering, error) {
+	panic("unimplemented")
+}
+
+// An Ordering holds the computed visual order of runs of a Paragraph. Calling
+// SetBytes or SetString on the originating Paragraph invalidates an Ordering.
+// The methods of an Ordering should only be called by one goroutine at a time.
+type Ordering struct{}
+
+// Direction reports the directionality of the runs.
+//
+// The direction may be LeftToRight, RightToLeft, Mixed, or Neutral.
+func (o *Ordering) Direction() Direction {
+	panic("unimplemented")
+}
+
+// NumRuns returns the number of runs.
+func (o *Ordering) NumRuns() int {
+	panic("unimplemented")
+}
+
+// Run returns the ith run within the ordering.
+func (o *Ordering) Run(i int) Run {
+	panic("unimplemented")
+}
+
+// TODO: perhaps with options.
+// // Reorder creates a reader that reads the runes in visual order per character.
+// // Modifiers remain after the runes they modify.
+// func (l *Runs) Reorder() io.Reader {
+// 	panic("unimplemented")
+// }
+
+// A Run is a continuous sequence of characters of a single direction.
+type Run struct {
+}
+
+// String returns the text of the run in its original order.
+func (r *Run) String() string {
+	panic("unimplemented")
+}
+
+// Bytes returns the text of the run in its original order.
+func (r *Run) Bytes() []byte {
+	panic("unimplemented")
+}
+
+// TODO: methods for
+// - Display order
+// - headers and footers
+// - bracket replacement.
+
+// Direction reports the direction of the run.
+func (r *Run) Direction() Direction {
+	panic("unimplemented")
+}
+
+// Position of the Run within the text passed to SetBytes or SetString of the
+// originating Paragraph value.
+func (r *Run) Pos() (start, end int) {
+	panic("unimplemented")
+}
+
+// AppendReverse reverses the order of characters of in, appends them to out,
+// and returns the result. Modifiers will still follow the runes they modify.
+// Brackets are replaced with their counterparts.
+func AppendReverse(out, in []byte) []byte {
+	panic("unimplemented")
+}
+
+// ReverseString reverses the order of characters in s and returns a new string.
+// Modifiers will still follow the runes they modify. Brackets are replaced with
+// their counterparts.
+func ReverseString(s string) string {
+	panic("unimplemented")
+}

vendor/golang.org/x/text/unicode/bidi/bracket.go

@@ -0,0 +1,335 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bidi
+
+import (
+	"container/list"
+	"fmt"
+	"sort"
+)
+
+// This file contains a port of the reference implementation of the
+// Bidi Parentheses Algorithm:
+// http://www.unicode.org/Public/PROGRAMS/BidiReferenceJava/BidiPBAReference.java
+//
+// The implementation in this file covers definitions BD14-BD16 and rule N0
+// of UAX#9.
+//
+// Some preprocessing is done for each rune before data is passed to this
+// algorithm:
+//  - opening and closing brackets are identified
+//  - a bracket pair type, like '(' and ')' is assigned a unique identifier that
+//    is identical for the opening and closing bracket. It is left to do these
+//    mappings.
+//  - The BPA algorithm requires that bracket characters that are canonical
+//    equivalents of each other be able to be substituted for each other.
+//    It is the responsibility of the caller to do this canonicalization.
+//
+// In implementing BD16, this implementation departs slightly from the "logical"
+// algorithm defined in UAX#9. In particular, the stack referenced there
+// supports operations that go beyond a "basic" stack. An equivalent
+// implementation based on a linked list is used here.
+
+// Bidi_Paired_Bracket_Type
+// BD14. An opening paired bracket is a character whose
+// Bidi_Paired_Bracket_Type property value is Open.
+//
+// BD15. A closing paired bracket is a character whose
+// Bidi_Paired_Bracket_Type property value is Close.
+type bracketType byte
+
+const (
+	bpNone bracketType = iota
+	bpOpen
+	bpClose
+)
+
+// bracketPair holds a pair of index values for opening and closing bracket
+// location of a bracket pair.
+type bracketPair struct {
+	opener int
+	closer int
+}
+
+func (b *bracketPair) String() string {
+	return fmt.Sprintf("(%v, %v)", b.opener, b.closer)
+}
+
+// bracketPairs is a slice of bracketPairs with a sort.Interface implementation.
+type bracketPairs []bracketPair
+
+func (b bracketPairs) Len() int           { return len(b) }
+func (b bracketPairs) Swap(i, j int)      { b[i], b[j] = b[j], b[i] }
+func (b bracketPairs) Less(i, j int) bool { return b[i].opener < b[j].opener }
+
+// resolvePairedBrackets runs the paired bracket part of the UBA algorithm.
+//
+// For each rune, it takes the indexes into the original string, the class the
+// bracket type (in pairTypes) and the bracket identifier (pairValues). It also
+// takes the direction type for the start-of-sentence and the embedding level.
+//
+// The identifiers for bracket types are the rune of the canonicalized opening
+// bracket for brackets (open or close) or 0 for runes that are not brackets.
+func resolvePairedBrackets(s *isolatingRunSequence) {
+	p := bracketPairer{
+		sos:              s.sos,
+		openers:          list.New(),
+		codesIsolatedRun: s.types,
+		indexes:          s.indexes,
+	}
+	dirEmbed := L
+	if s.level&1 != 0 {
+		dirEmbed = R
+	}
+	p.locateBrackets(s.p.pairTypes, s.p.pairValues)
+	p.resolveBrackets(dirEmbed, s.p.initialTypes)
+}
+
+type bracketPairer struct {
+	sos Class // direction corresponding to start of sequence
+
+	// The following is a restatement of BD 16 using non-algorithmic language.
+	//
+	// A bracket pair is a pair of characters consisting of an opening
+	// paired bracket and a closing paired bracket such that the
+	// Bidi_Paired_Bracket property value of the former equals the latter,
+	// subject to the following constraints.
+	// - both characters of a pair occur in the same isolating run sequence
+	// - the closing character of a pair follows the opening character
+	// - any bracket character can belong at most to one pair, the earliest possible one
+	// - any bracket character not part of a pair is treated like an ordinary character
+	// - pairs may nest properly, but their spans may not overlap otherwise
+
+	// Bracket characters with canonical decompositions are supposed to be
+	// treated as if they had been normalized, to allow normalized and non-
+	// normalized text to give the same result. In this implementation that step
+	// is pushed out to the caller. The caller has to ensure that the pairValue
+	// slices contain the rune of the opening bracket after normalization for
+	// any opening or closing bracket.
+
+	openers *list.List // list of positions for opening brackets
+
+	// bracket pair positions sorted by location of opening bracket
+	pairPositions bracketPairs
+
+	codesIsolatedRun []Class // directional bidi codes for an isolated run
+	indexes          []int   // array of index values into the original string
+
+}
+
+// matchOpener reports whether characters at given positions form a matching
+// bracket pair.
+func (p *bracketPairer) matchOpener(pairValues []rune, opener, closer int) bool {
+	return pairValues[p.indexes[opener]] == pairValues[p.indexes[closer]]
+}
+
+const maxPairingDepth = 63
+
+// locateBrackets locates matching bracket pairs according to BD16.
+//
+// This implementation uses a linked list instead of a stack, because, while
+// elements are added at the front (like a push) they are not generally removed
+// in atomic 'pop' operations, reducing the benefit of the stack archetype.
+func (p *bracketPairer) locateBrackets(pairTypes []bracketType, pairValues []rune) {
+	// traverse the run
+	// do that explicitly (not in a for-each) so we can record position
+	for i, index := range p.indexes {
+
+		// look at the bracket type for each character
+		if pairTypes[index] == bpNone || p.codesIsolatedRun[i] != ON {
+			// continue scanning
+			continue
+		}
+		switch pairTypes[index] {
+		case bpOpen:
+			// check if maximum pairing depth reached
+			if p.openers.Len() == maxPairingDepth {
+				p.openers.Init()
+				return
+			}
+			// remember opener location, most recent first
+			p.openers.PushFront(i)
+
+		case bpClose:
+			// see if there is a match
+			count := 0
+			for elem := p.openers.Front(); elem != nil; elem = elem.Next() {
+				count++
+				opener := elem.Value.(int)
+				if p.matchOpener(pairValues, opener, i) {
+					// if the opener matches, add nested pair to the ordered list
+					p.pairPositions = append(p.pairPositions, bracketPair{opener, i})
+					// remove up to and including matched opener
+					for ; count > 0; count-- {
+						p.openers.Remove(p.openers.Front())
+					}
+					break
+				}
+			}
+			sort.Sort(p.pairPositions)
+			// if we get here, the closing bracket matched no openers
+			// and gets ignored
+		}
+	}
+}
+
+// Bracket pairs within an isolating run sequence are processed as units so
+// that both the opening and the closing paired bracket in a pair resolve to
+// the same direction.
+//
+// N0. Process bracket pairs in an isolating run sequence sequentially in
+// the logical order of the text positions of the opening paired brackets
+// using the logic given below. Within this scope, bidirectional types EN
+// and AN are treated as R.
+//
+// Identify the bracket pairs in the current isolating run sequence
+// according to BD16. For each bracket-pair element in the list of pairs of
+// text positions:
+//
+// a Inspect the bidirectional types of the characters enclosed within the
+// bracket pair.
+//
+// b If any strong type (either L or R) matching the embedding direction is
+// found, set the type for both brackets in the pair to match the embedding
+// direction.
+//
+// o [ e ] o -> o e e e o
+//
+// o [ o e ] -> o e o e e
+//
+// o [ NI e ] -> o e NI e e
+//
+// c Otherwise, if a strong type (opposite the embedding direction) is
+// found, test for adjacent strong types as follows: 1 First, check
+// backwards before the opening paired bracket until the first strong type
+// (L, R, or sos) is found. If that first preceding strong type is opposite
+// the embedding direction, then set the type for both brackets in the pair
+// to that type. 2 Otherwise, set the type for both brackets in the pair to
+// the embedding direction.
+//
+// o [ o ] e -> o o o o e
+//
+// o [ o NI ] o -> o o o NI o o
+//
+// e [ o ] o -> e e o e o
+//
+// e [ o ] e -> e e o e e
+//
+// e ( o [ o ] NI ) e -> e e o o o o NI e e
+//
+// d Otherwise, do not set the type for the current bracket pair. Note that
+// if the enclosed text contains no strong types the paired brackets will
+// both resolve to the same level when resolved individually using rules N1
+// and N2.
+//
+// e ( NI ) o -> e ( NI ) o
+
+// getStrongTypeN0 maps character's directional code to strong type as required
+// by rule N0.
+//
+// TODO: have separate type for "strong" directionality.
+func (p *bracketPairer) getStrongTypeN0(index int) Class {
+	switch p.codesIsolatedRun[index] {
+	// in the scope of N0, number types are treated as R
+	case EN, AN, AL, R:
+		return R
+	case L:
+		return L
+	default:
+		return ON
+	}
+}
+
+// classifyPairContent reports the strong types contained inside a Bracket Pair,
+// assuming the given embedding direction.
+//
+// It returns ON if no strong type is found. If a single strong type is found,
+// it returns this this type. Otherwise it returns the embedding direction.
+//
+// TODO: use separate type for "strong" directionality.
+func (p *bracketPairer) classifyPairContent(loc bracketPair, dirEmbed Class) Class {
+	dirOpposite := ON
+	for i := loc.opener + 1; i < loc.closer; i++ {
+		dir := p.getStrongTypeN0(i)
+		if dir == ON {
+			continue
+		}
+		if dir == dirEmbed {
+			return dir // type matching embedding direction found
+		}
+		dirOpposite = dir
+	}
+	// return ON if no strong type found, or class opposite to dirEmbed
+	return dirOpposite
+}
+
+// classBeforePair determines which strong types are present before a Bracket
+// Pair. Return R or L if strong type found, otherwise ON.
+func (p *bracketPairer) classBeforePair(loc bracketPair) Class {
+	for i := loc.opener - 1; i >= 0; i-- {
+		if dir := p.getStrongTypeN0(i); dir != ON {
+			return dir
+		}
+	}
+	// no strong types found, return sos
+	return p.sos
+}
+
+// assignBracketType implements rule N0 for a single bracket pair.
+func (p *bracketPairer) assignBracketType(loc bracketPair, dirEmbed Class, initialTypes []Class) {
+	// rule "N0, a", inspect contents of pair
+	dirPair := p.classifyPairContent(loc, dirEmbed)
+
+	// dirPair is now L, R, or N (no strong type found)
+
+	// the following logical tests are performed out of order compared to
+	// the statement of the rules but yield the same results
+	if dirPair == ON {
+		return // case "d" - nothing to do
+	}
+
+	if dirPair != dirEmbed {
+		// case "c": strong type found, opposite - check before (c.1)
+		dirPair = p.classBeforePair(loc)
+		if dirPair == dirEmbed || dirPair == ON {
+			// no strong opposite type found before - use embedding (c.2)
+			dirPair = dirEmbed
+		}
+	}
+	// else: case "b", strong type found matching embedding,
+	// no explicit action needed, as dirPair is already set to embedding
+	// direction
+
+	// set the bracket types to the type found
+	p.setBracketsToType(loc, dirPair, initialTypes)
+}
+
+func (p *bracketPairer) setBracketsToType(loc bracketPair, dirPair Class, initialTypes []Class) {
+	p.codesIsolatedRun[loc.opener] = dirPair
+	p.codesIsolatedRun[loc.closer] = dirPair
+
+	for i := loc.opener + 1; i < loc.closer; i++ {
+		index := p.indexes[i]
+		if initialTypes[index] != NSM {
+			break
+		}
+		p.codesIsolatedRun[i] = dirPair
+	}
+
+	for i := loc.closer + 1; i < len(p.indexes); i++ {
+		index := p.indexes[i]
+		if initialTypes[index] != NSM {
+			break
+		}
+		p.codesIsolatedRun[i] = dirPair
+	}
+}
+
+// resolveBrackets implements rule N0 for a list of pairs.
+func (p *bracketPairer) resolveBrackets(dirEmbed Class, initialTypes []Class) {
+	for _, loc := range p.pairPositions {
+		p.assignBracketType(loc, dirEmbed, initialTypes)
+	}
+}

vendor/golang.org/x/text/unicode/bidi/gen.go

@@ -0,0 +1,133 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+
+package main
+
+import (
+	"flag"
+	"log"
+
+	"golang.org/x/text/internal/gen"
+	"golang.org/x/text/internal/triegen"
+	"golang.org/x/text/internal/ucd"
+)
+
+var outputFile = flag.String("out", "tables.go", "output file")
+
+func main() {
+	gen.Init()
+	gen.Repackage("gen_trieval.go", "trieval.go", "bidi")
+	gen.Repackage("gen_ranges.go", "ranges_test.go", "bidi")
+
+	genTables()
+}
+
+// bidiClass names and codes taken from class "bc" in
+// http://www.unicode.org/Public/8.0.0/ucd/PropertyValueAliases.txt
+var bidiClass = map[string]Class{
+	"AL":  AL,  // ArabicLetter
+	"AN":  AN,  // ArabicNumber
+	"B":   B,   // ParagraphSeparator
+	"BN":  BN,  // BoundaryNeutral
+	"CS":  CS,  // CommonSeparator
+	"EN":  EN,  // EuropeanNumber
+	"ES":  ES,  // EuropeanSeparator
+	"ET":  ET,  // EuropeanTerminator
+	"L":   L,   // LeftToRight
+	"NSM": NSM, // NonspacingMark
+	"ON":  ON,  // OtherNeutral
+	"R":   R,   // RightToLeft
+	"S":   S,   // SegmentSeparator
+	"WS":  WS,  // WhiteSpace
+
+	"FSI": Control,
+	"PDF": Control,
+	"PDI": Control,
+	"LRE": Control,
+	"LRI": Control,
+	"LRO": Control,
+	"RLE": Control,
+	"RLI": Control,
+	"RLO": Control,
+}
+
+func genTables() {
+	if numClass > 0x0F {
+		log.Fatalf("Too many Class constants (%#x > 0x0F).", numClass)
+	}
+	w := gen.NewCodeWriter()
+	defer w.WriteGoFile(*outputFile, "bidi")
+
+	gen.WriteUnicodeVersion(w)
+
+	t := triegen.NewTrie("bidi")
+
+	// Build data about bracket mapping. These bits need to be or-ed with
+	// any other bits.
+	orMask := map[rune]uint64{}
+
+	xorMap := map[rune]int{}
+	xorMasks := []rune{0} // First value is no-op.
+
+	ucd.Parse(gen.OpenUCDFile("BidiBrackets.txt"), func(p *ucd.Parser) {
+		r1 := p.Rune(0)
+		r2 := p.Rune(1)
+		xor := r1 ^ r2
+		if _, ok := xorMap[xor]; !ok {
+			xorMap[xor] = len(xorMasks)
+			xorMasks = append(xorMasks, xor)
+		}
+		entry := uint64(xorMap[xor]) << xorMaskShift
+		switch p.String(2) {
+		case "o":
+			entry |= openMask
+		case "c", "n":
+		default:
+			log.Fatalf("Unknown bracket class %q.", p.String(2))
+		}
+		orMask[r1] = entry
+	})
+
+	w.WriteComment(`
+	xorMasks contains masks to be xor-ed with brackets to get the reverse
+	version.`)
+	w.WriteVar("xorMasks", xorMasks)
+
+	done := map[rune]bool{}
+
+	insert := func(r rune, c Class) {
+		if !done[r] {
+			t.Insert(r, orMask[r]|uint64(c))
+			done[r] = true
+		}
+	}
+
+	// Insert the derived BiDi properties.
+	ucd.Parse(gen.OpenUCDFile("extracted/DerivedBidiClass.txt"), func(p *ucd.Parser) {
+		r := p.Rune(0)
+		class, ok := bidiClass[p.String(1)]
+		if !ok {
+			log.Fatalf("%U: Unknown BiDi class %q", r, p.String(1))
+		}
+		insert(r, class)
+	})
+	visitDefaults(insert)
+
+	// TODO: use sparse blocks. This would reduce table size considerably
+	// from the looks of it.
+
+	sz, err := t.Gen(w)
+	if err != nil {
+		log.Fatal(err)
+	}
+	w.Size += sz
+}
+
+// dummy values to make methods in gen_common compile. The real versions
+// will be generated by this file to tables.go.
+var (
+	xorMasks []rune
+)

vendor/golang.org/x/text/unicode/bidi/gen_ranges.go

@@ -0,0 +1,57 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+
+package main
+
+import (
+	"unicode"
+
+	"golang.org/x/text/internal/gen"
+	"golang.org/x/text/internal/ucd"
+	"golang.org/x/text/unicode/rangetable"
+)
+
+// These tables are hand-extracted from:
+// http://www.unicode.org/Public/8.0.0/ucd/extracted/DerivedBidiClass.txt
+func visitDefaults(fn func(r rune, c Class)) {
+	// first write default values for ranges listed above.
+	visitRunes(fn, AL, []rune{
+		0x0600, 0x07BF, // Arabic
+		0x08A0, 0x08FF, // Arabic Extended-A
+		0xFB50, 0xFDCF, // Arabic Presentation Forms
+		0xFDF0, 0xFDFF,
+		0xFE70, 0xFEFF,
+		0x0001EE00, 0x0001EEFF, // Arabic Mathematical Alpha Symbols
+	})
+	visitRunes(fn, R, []rune{
+		0x0590, 0x05FF, // Hebrew
+		0x07C0, 0x089F, // Nko et al.
+		0xFB1D, 0xFB4F,
+		0x00010800, 0x00010FFF, // Cypriot Syllabary et. al.
+		0x0001E800, 0x0001EDFF,
+		0x0001EF00, 0x0001EFFF,
+	})
+	visitRunes(fn, ET, []rune{ // European Terminator
+		0x20A0, 0x20Cf, // Currency symbols
+	})
+	rangetable.Visit(unicode.Noncharacter_Code_Point, func(r rune) {
+		fn(r, BN) // Boundary Neutral
+	})
+	ucd.Parse(gen.OpenUCDFile("DerivedCoreProperties.txt"), func(p *ucd.Parser) {
+		if p.String(1) == "Default_Ignorable_Code_Point" {
+			fn(p.Rune(0), BN) // Boundary Neutral
+		}
+	})
+}
+
+func visitRunes(fn func(r rune, c Class), c Class, runes []rune) {
+	for i := 0; i < len(runes); i += 2 {
+		lo, hi := runes[i], runes[i+1]
+		for j := lo; j <= hi; j++ {
+			fn(j, c)
+		}
+	}
+}

vendor/golang.org/x/text/unicode/bidi/gen_trieval.go

@@ -0,0 +1,64 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+
+package main
+
+// Class is the Unicode BiDi class. Each rune has a single class.
+type Class uint
+
+const (
+	L       Class = iota // LeftToRight
+	R                    // RightToLeft
+	EN                   // EuropeanNumber
+	ES                   // EuropeanSeparator
+	ET                   // EuropeanTerminator
+	AN                   // ArabicNumber
+	CS                   // CommonSeparator
+	B                    // ParagraphSeparator
+	S                    // SegmentSeparator
+	WS                   // WhiteSpace
+	ON                   // OtherNeutral
+	BN                   // BoundaryNeutral
+	NSM                  // NonspacingMark
+	AL                   // ArabicLetter
+	Control              // Control LRO - PDI
+
+	numClass
+
+	LRO // LeftToRightOverride
+	RLO // RightToLeftOverride
+	LRE // LeftToRightEmbedding
+	RLE // RightToLeftEmbedding
+	PDF // PopDirectionalFormat
+	LRI // LeftToRightIsolate
+	RLI // RightToLeftIsolate
+	FSI // FirstStrongIsolate
+	PDI // PopDirectionalIsolate
+
+	unknownClass = ^Class(0)
+)
+
+var controlToClass = map[rune]Class{
+	0x202D: LRO, // LeftToRightOverride,
+	0x202E: RLO, // RightToLeftOverride,
+	0x202A: LRE, // LeftToRightEmbedding,
+	0x202B: RLE, // RightToLeftEmbedding,
+	0x202C: PDF, // PopDirectionalFormat,
+	0x2066: LRI, // LeftToRightIsolate,
+	0x2067: RLI, // RightToLeftIsolate,
+	0x2068: FSI, // FirstStrongIsolate,
+	0x2069: PDI, // PopDirectionalIsolate,
+}
+
+// A trie entry has the following bits:
+// 7..5  XOR mask for brackets
+// 4     1: Bracket open, 0: Bracket close
+// 3..0  Class type
+
+const (
+	openMask     = 0x10
+	xorMaskShift = 5
+)

vendor/golang.org/x/text/unicode/bidi/prop.go

@@ -0,0 +1,206 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bidi
+
+import "unicode/utf8"
+
+// Properties provides access to BiDi properties of runes.
+type Properties struct {
+	entry uint8
+	last  uint8
+}
+
+var trie = newBidiTrie(0)
+
+// TODO: using this for bidirule reduces the running time by about 5%. Consider
+// if this is worth exposing or if we can find a way to speed up the Class
+// method.
+//
+// // CompactClass is like Class, but maps all of the BiDi control classes
+// // (LRO, RLO, LRE, RLE, PDF, LRI, RLI, FSI, PDI) to the class Control.
+// func (p Properties) CompactClass() Class {
+// 	return Class(p.entry & 0x0F)
+// }
+
+// Class returns the Bidi class for p.
+func (p Properties) Class() Class {
+	c := Class(p.entry & 0x0F)
+	if c == Control {
+		c = controlByteToClass[p.last&0xF]
+	}
+	return c
+}
+
+// IsBracket reports whether the rune is a bracket.
+func (p Properties) IsBracket() bool { return p.entry&0xF0 != 0 }
+
+// IsOpeningBracket reports whether the rune is an opening bracket.
+// IsBracket must return true.
+func (p Properties) IsOpeningBracket() bool { return p.entry&openMask != 0 }
+
+// TODO: find a better API and expose.
+func (p Properties) reverseBracket(r rune) rune {
+	return xorMasks[p.entry>>xorMaskShift] ^ r
+}
+
+var controlByteToClass = [16]Class{
+	0xD: LRO, // U+202D LeftToRightOverride,
+	0xE: RLO, // U+202E RightToLeftOverride,
+	0xA: LRE, // U+202A LeftToRightEmbedding,
+	0xB: RLE, // U+202B RightToLeftEmbedding,
+	0xC: PDF, // U+202C PopDirectionalFormat,
+	0x6: LRI, // U+2066 LeftToRightIsolate,
+	0x7: RLI, // U+2067 RightToLeftIsolate,
+	0x8: FSI, // U+2068 FirstStrongIsolate,
+	0x9: PDI, // U+2069 PopDirectionalIsolate,
+}
+
+// LookupRune returns properties for r.
+func LookupRune(r rune) (p Properties, size int) {
+	var buf [4]byte
+	n := utf8.EncodeRune(buf[:], r)
+	return Lookup(buf[:n])
+}
+
+// TODO: these lookup methods are based on the generated trie code. The returned
+// sizes have slightly different semantics from the generated code, in that it
+// always returns size==1 for an illegal UTF-8 byte (instead of the length
+// of the maximum invalid subsequence). Most Transformers, like unicode/norm,
+// leave invalid UTF-8 untouched, in which case it has performance benefits to
+// do so (without changing the semantics). Bidi requires the semantics used here
+// for the bidirule implementation to be compatible with the Go semantics.
+//  They ultimately should perhaps be adopted by all trie implementations, for
+// convenience sake.
+// This unrolled code also boosts performance of the secure/bidirule package by
+// about 30%.
+// So, to remove this code:
+//   - add option to trie generator to define return type.
+//   - always return 1 byte size for ill-formed UTF-8 runes.
+
+// Lookup returns properties for the first rune in s and the width in bytes of
+// its encoding. The size will be 0 if s does not hold enough bytes to complete
+// the encoding.
+func Lookup(s []byte) (p Properties, sz int) {
+	c0 := s[0]
+	switch {
+	case c0 < 0x80: // is ASCII
+		return Properties{entry: bidiValues[c0]}, 1
+	case c0 < 0xC2:
+		return Properties{}, 1
+	case c0 < 0xE0: // 2-byte UTF-8
+		if len(s) < 2 {
+			return Properties{}, 0
+		}
+		i := bidiIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return Properties{}, 1
+		}
+		return Properties{entry: trie.lookupValue(uint32(i), c1)}, 2
+	case c0 < 0xF0: // 3-byte UTF-8
+		if len(s) < 3 {
+			return Properties{}, 0
+		}
+		i := bidiIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return Properties{}, 1
+		}
+		o := uint32(i)<<6 + uint32(c1)
+		i = bidiIndex[o]
+		c2 := s[2]
+		if c2 < 0x80 || 0xC0 <= c2 {
+			return Properties{}, 1
+		}
+		return Properties{entry: trie.lookupValue(uint32(i), c2), last: c2}, 3
+	case c0 < 0xF8: // 4-byte UTF-8
+		if len(s) < 4 {
+			return Properties{}, 0
+		}
+		i := bidiIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return Properties{}, 1
+		}
+		o := uint32(i)<<6 + uint32(c1)
+		i = bidiIndex[o]
+		c2 := s[2]
+		if c2 < 0x80 || 0xC0 <= c2 {
+			return Properties{}, 1
+		}
+		o = uint32(i)<<6 + uint32(c2)
+		i = bidiIndex[o]
+		c3 := s[3]
+		if c3 < 0x80 || 0xC0 <= c3 {
+			return Properties{}, 1
+		}
+		return Properties{entry: trie.lookupValue(uint32(i), c3)}, 4
+	}
+	// Illegal rune
+	return Properties{}, 1
+}
+
+// LookupString returns properties for the first rune in s and the width in
+// bytes of its encoding. The size will be 0 if s does not hold enough bytes to
+// complete the encoding.
+func LookupString(s string) (p Properties, sz int) {
+	c0 := s[0]
+	switch {
+	case c0 < 0x80: // is ASCII
+		return Properties{entry: bidiValues[c0]}, 1
+	case c0 < 0xC2:
+		return Properties{}, 1
+	case c0 < 0xE0: // 2-byte UTF-8
+		if len(s) < 2 {
+			return Properties{}, 0
+		}
+		i := bidiIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return Properties{}, 1
+		}
+		return Properties{entry: trie.lookupValue(uint32(i), c1)}, 2
+	case c0 < 0xF0: // 3-byte UTF-8
+		if len(s) < 3 {
+			return Properties{}, 0
+		}
+		i := bidiIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return Properties{}, 1
+		}
+		o := uint32(i)<<6 + uint32(c1)
+		i = bidiIndex[o]
+		c2 := s[2]
+		if c2 < 0x80 || 0xC0 <= c2 {
+			return Properties{}, 1
+		}
+		return Properties{entry: trie.lookupValue(uint32(i), c2), last: c2}, 3
+	case c0 < 0xF8: // 4-byte UTF-8
+		if len(s) < 4 {
+			return Properties{}, 0
+		}
+		i := bidiIndex[c0]
+		c1 := s[1]
+		if c1 < 0x80 || 0xC0 <= c1 {
+			return Properties{}, 1
+		}
+		o := uint32(i)<<6 + uint32(c1)
+		i = bidiIndex[o]
+		c2 := s[2]
+		if c2 < 0x80 || 0xC0 <= c2 {
+			return Properties{}, 1
+		}
+		o = uint32(i)<<6 + uint32(c2)
+		i = bidiIndex[o]
+		c3 := s[3]
+		if c3 < 0x80 || 0xC0 <= c3 {
+			return Properties{}, 1
+		}
+		return Properties{entry: trie.lookupValue(uint32(i), c3)}, 4
+	}
+	// Illegal rune
+	return Properties{}, 1
+}

vendor/golang.org/x/text/unicode/bidi/trieval.go

@@ -0,0 +1,60 @@
+// Code generated by running "go generate" in golang.org/x/text. DO NOT EDIT.
+
+package bidi
+
+// Class is the Unicode BiDi class. Each rune has a single class.
+type Class uint
+
+const (
+	L       Class = iota // LeftToRight
+	R                    // RightToLeft
+	EN                   // EuropeanNumber
+	ES                   // EuropeanSeparator
+	ET                   // EuropeanTerminator
+	AN                   // ArabicNumber
+	CS                   // CommonSeparator
+	B                    // ParagraphSeparator
+	S                    // SegmentSeparator
+	WS                   // WhiteSpace
+	ON                   // OtherNeutral
+	BN                   // BoundaryNeutral
+	NSM                  // NonspacingMark
+	AL                   // ArabicLetter
+	Control              // Control LRO - PDI
+
+	numClass
+
+	LRO // LeftToRightOverride
+	RLO // RightToLeftOverride
+	LRE // LeftToRightEmbedding
+	RLE // RightToLeftEmbedding
+	PDF // PopDirectionalFormat
+	LRI // LeftToRightIsolate
+	RLI // RightToLeftIsolate
+	FSI // FirstStrongIsolate
+	PDI // PopDirectionalIsolate
+
+	unknownClass = ^Class(0)
+)
+
+var controlToClass = map[rune]Class{
+	0x202D: LRO, // LeftToRightOverride,
+	0x202E: RLO, // RightToLeftOverride,
+	0x202A: LRE, // LeftToRightEmbedding,
+	0x202B: RLE, // RightToLeftEmbedding,
+	0x202C: PDF, // PopDirectionalFormat,
+	0x2066: LRI, // LeftToRightIsolate,
+	0x2067: RLI, // RightToLeftIsolate,
+	0x2068: FSI, // FirstStrongIsolate,
+	0x2069: PDI, // PopDirectionalIsolate,
+}
+
+// A trie entry has the following bits:
+// 7..5  XOR mask for brackets
+// 4     1: Bracket open, 0: Bracket close
+// 3..0  Class type
+
+const (
+	openMask     = 0x10
+	xorMaskShift = 5
+)

vendor/golang.org/x/text/unicode/norm/composition.go

@@ -0,0 +1,514 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package norm
+
+import "unicode/utf8"
+
+const (
+	maxNonStarters = 30
+	// The maximum number of characters needed for a buffer is
+	// maxNonStarters + 1 for the starter + 1 for the GCJ
+	maxBufferSize    = maxNonStarters + 2
+	maxNFCExpansion  = 3  // NFC(0x1D160)
+	maxNFKCExpansion = 18 // NFKC(0xFDFA)
+
+	maxByteBufferSize = utf8.UTFMax * maxBufferSize // 128
+)
+
+// ssState is used for reporting the segment state after inserting a rune.
+// It is returned by streamSafe.next.
+type ssState int
+
+const (
+	// Indicates a rune was successfully added to the segment.
+	ssSuccess ssState = iota
+	// Indicates a rune starts a new segment and should not be added.
+	ssStarter
+	// Indicates a rune caused a segment overflow and a CGJ should be inserted.
+	ssOverflow
+)
+
+// streamSafe implements the policy of when a CGJ should be inserted.
+type streamSafe uint8
+
+// mkStreamSafe is a shorthand for declaring a streamSafe var and calling
+// first on it.
+func mkStreamSafe(p Properties) streamSafe {
+	return streamSafe(p.nTrailingNonStarters())
+}
+
+// first inserts the first rune of a segment.
+func (ss *streamSafe) first(p Properties) {
+	if *ss != 0 {
+		panic("!= 0")
+	}
+	*ss = streamSafe(p.nTrailingNonStarters())
+}
+
+// insert returns a ssState value to indicate whether a rune represented by p
+// can be inserted.
+func (ss *streamSafe) next(p Properties) ssState {
+	if *ss > maxNonStarters {
+		panic("streamSafe was not reset")
+	}
+	n := p.nLeadingNonStarters()
+	if *ss += streamSafe(n); *ss > maxNonStarters {
+		*ss = 0
+		return ssOverflow
+	}
+	// The Stream-Safe Text Processing prescribes that the counting can stop
+	// as soon as a starter is encountered. However, there are some starters,
+	// like Jamo V and T, that can combine with other runes, leaving their
+	// successive non-starters appended to the previous, possibly causing an
+	// overflow. We will therefore consider any rune with a non-zero nLead to
+	// be a non-starter. Note that it always hold that if nLead > 0 then
+	// nLead == nTrail.
+	if n == 0 {
+		*ss = 0
+		return ssStarter
+	}
+	return ssSuccess
+}
+
+// backwards is used for checking for overflow and segment starts
+// when traversing a string backwards. Users do not need to call first
+// for the first rune. The state of the streamSafe retains the count of
+// the non-starters loaded.
+func (ss *streamSafe) backwards(p Properties) ssState {
+	if *ss > maxNonStarters {
+		panic("streamSafe was not reset")
+	}
+	c := *ss + streamSafe(p.nTrailingNonStarters())
+	if c > maxNonStarters {
+		return ssOverflow
+	}
+	*ss = c
+	if p.nLeadingNonStarters() == 0 {
+		return ssStarter
+	}
+	return ssSuccess
+}
+
+func (ss streamSafe) isMax() bool {
+	return ss == maxNonStarters
+}
+
+// GraphemeJoiner is inserted after maxNonStarters non-starter runes.
+const GraphemeJoiner = "\u034F"
+
+// reorderBuffer is used to normalize a single segment.  Characters inserted with
+// insert are decomposed and reordered based on CCC. The compose method can
+// be used to recombine characters.  Note that the byte buffer does not hold
+// the UTF-8 characters in order.  Only the rune array is maintained in sorted
+// order. flush writes the resulting segment to a byte array.
+type reorderBuffer struct {
+	rune  [maxBufferSize]Properties // Per character info.
+	byte  [maxByteBufferSize]byte   // UTF-8 buffer. Referenced by runeInfo.pos.
+	nbyte uint8                     // Number or bytes.
+	ss    streamSafe                // For limiting length of non-starter sequence.
+	nrune int                       // Number of runeInfos.
+	f     formInfo
+
+	src      input
+	nsrc     int
+	tmpBytes input
+
+	out    []byte
+	flushF func(*reorderBuffer) bool
+}
+
+func (rb *reorderBuffer) init(f Form, src []byte) {
+	rb.f = *formTable[f]
+	rb.src.setBytes(src)
+	rb.nsrc = len(src)
+	rb.ss = 0
+}
+
+func (rb *reorderBuffer) initString(f Form, src string) {
+	rb.f = *formTable[f]
+	rb.src.setString(src)
+	rb.nsrc = len(src)
+	rb.ss = 0
+}
+
+func (rb *reorderBuffer) setFlusher(out []byte, f func(*reorderBuffer) bool) {
+	rb.out = out
+	rb.flushF = f
+}
+
+// reset discards all characters from the buffer.
+func (rb *reorderBuffer) reset() {
+	rb.nrune = 0
+	rb.nbyte = 0
+	rb.ss = 0
+}
+
+func (rb *reorderBuffer) doFlush() bool {
+	if rb.f.composing {
+		rb.compose()
+	}
+	res := rb.flushF(rb)
+	rb.reset()
+	return res
+}
+
+// appendFlush appends the normalized segment to rb.out.
+func appendFlush(rb *reorderBuffer) bool {
+	for i := 0; i < rb.nrune; i++ {
+		start := rb.rune[i].pos
+		end := start + rb.rune[i].size
+		rb.out = append(rb.out, rb.byte[start:end]...)
+	}
+	return true
+}
+
+// flush appends the normalized segment to out and resets rb.
+func (rb *reorderBuffer) flush(out []byte) []byte {
+	for i := 0; i < rb.nrune; i++ {
+		start := rb.rune[i].pos
+		end := start + rb.rune[i].size
+		out = append(out, rb.byte[start:end]...)
+	}
+	rb.reset()
+	return out
+}
+
+// flushCopy copies the normalized segment to buf and resets rb.
+// It returns the number of bytes written to buf.
+func (rb *reorderBuffer) flushCopy(buf []byte) int {
+	p := 0
+	for i := 0; i < rb.nrune; i++ {
+		runep := rb.rune[i]
+		p += copy(buf[p:], rb.byte[runep.pos:runep.pos+runep.size])
+	}
+	rb.reset()
+	return p
+}
+
+// insertOrdered inserts a rune in the buffer, ordered by Canonical Combining Class.
+// It returns false if the buffer is not large enough to hold the rune.
+// It is used internally by insert and insertString only.
+func (rb *reorderBuffer) insertOrdered(info Properties) {
+	n := rb.nrune
+	b := rb.rune[:]
+	cc := info.ccc
+	if cc > 0 {
+		// Find insertion position + move elements to make room.
+		for ; n > 0; n-- {
+			if b[n-1].ccc <= cc {
+				break
+			}
+			b[n] = b[n-1]
+		}
+	}
+	rb.nrune += 1
+	pos := uint8(rb.nbyte)
+	rb.nbyte += utf8.UTFMax
+	info.pos = pos
+	b[n] = info
+}
+
+// insertErr is an error code returned by insert. Using this type instead
+// of error improves performance up to 20% for many of the benchmarks.
+type insertErr int
+
+const (
+	iSuccess insertErr = -iota
+	iShortDst
+	iShortSrc
+)
+
+// insertFlush inserts the given rune in the buffer ordered by CCC.
+// If a decomposition with multiple segments are encountered, they leading
+// ones are flushed.
+// It returns a non-zero error code if the rune was not inserted.
+func (rb *reorderBuffer) insertFlush(src input, i int, info Properties) insertErr {
+	if rune := src.hangul(i); rune != 0 {
+		rb.decomposeHangul(rune)
+		return iSuccess
+	}
+	if info.hasDecomposition() {
+		return rb.insertDecomposed(info.Decomposition())
+	}
+	rb.insertSingle(src, i, info)
+	return iSuccess
+}
+
+// insertUnsafe inserts the given rune in the buffer ordered by CCC.
+// It is assumed there is sufficient space to hold the runes. It is the
+// responsibility of the caller to ensure this. This can be done by checking
+// the state returned by the streamSafe type.
+func (rb *reorderBuffer) insertUnsafe(src input, i int, info Properties) {
+	if rune := src.hangul(i); rune != 0 {
+		rb.decomposeHangul(rune)
+	}
+	if info.hasDecomposition() {
+		// TODO: inline.
+		rb.insertDecomposed(info.Decomposition())
+	} else {
+		rb.insertSingle(src, i, info)
+	}
+}
+
+// insertDecomposed inserts an entry in to the reorderBuffer for each rune
+// in dcomp. dcomp must be a sequence of decomposed UTF-8-encoded runes.
+// It flushes the buffer on each new segment start.
+func (rb *reorderBuffer) insertDecomposed(dcomp []byte) insertErr {
+	rb.tmpBytes.setBytes(dcomp)
+	for i := 0; i < len(dcomp); {
+		info := rb.f.info(rb.tmpBytes, i)
+		if info.BoundaryBefore() && rb.nrune > 0 && !rb.doFlush() {
+			return iShortDst
+		}
+		i += copy(rb.byte[rb.nbyte:], dcomp[i:i+int(info.size)])
+		rb.insertOrdered(info)
+	}
+	return iSuccess
+}
+
+// insertSingle inserts an entry in the reorderBuffer for the rune at
+// position i. info is the runeInfo for the rune at position i.
+func (rb *reorderBuffer) insertSingle(src input, i int, info Properties) {
+	src.copySlice(rb.byte[rb.nbyte:], i, i+int(info.size))
+	rb.insertOrdered(info)
+}
+
+// insertCGJ inserts a Combining Grapheme Joiner (0x034f) into rb.
+func (rb *reorderBuffer) insertCGJ() {
+	rb.insertSingle(input{str: GraphemeJoiner}, 0, Properties{size: uint8(len(GraphemeJoiner))})
+}
+
+// appendRune inserts a rune at the end of the buffer. It is used for Hangul.
+func (rb *reorderBuffer) appendRune(r rune) {
+	bn := rb.nbyte
+	sz := utf8.EncodeRune(rb.byte[bn:], rune(r))
+	rb.nbyte += utf8.UTFMax
+	rb.rune[rb.nrune] = Properties{pos: bn, size: uint8(sz)}
+	rb.nrune++
+}
+
+// assignRune sets a rune at position pos. It is used for Hangul and recomposition.
+func (rb *reorderBuffer) assignRune(pos int, r rune) {
+	bn := rb.rune[pos].pos
+	sz := utf8.EncodeRune(rb.byte[bn:], rune(r))
+	rb.rune[pos] = Properties{pos: bn, size: uint8(sz)}
+}
+
+// runeAt returns the rune at position n. It is used for Hangul and recomposition.
+func (rb *reorderBuffer) runeAt(n int) rune {
+	inf := rb.rune[n]
+	r, _ := utf8.DecodeRune(rb.byte[inf.pos : inf.pos+inf.size])
+	return r
+}
+
+// bytesAt returns the UTF-8 encoding of the rune at position n.
+// It is used for Hangul and recomposition.
+func (rb *reorderBuffer) bytesAt(n int) []byte {
+	inf := rb.rune[n]
+	return rb.byte[inf.pos : int(inf.pos)+int(inf.size)]
+}
+
+// For Hangul we combine algorithmically, instead of using tables.
+const (
+	hangulBase  = 0xAC00 // UTF-8(hangulBase) -> EA B0 80
+	hangulBase0 = 0xEA
+	hangulBase1 = 0xB0
+	hangulBase2 = 0x80
+
+	hangulEnd  = hangulBase + jamoLVTCount // UTF-8(0xD7A4) -> ED 9E A4
+	hangulEnd0 = 0xED
+	hangulEnd1 = 0x9E
+	hangulEnd2 = 0xA4
+
+	jamoLBase  = 0x1100 // UTF-8(jamoLBase) -> E1 84 00
+	jamoLBase0 = 0xE1
+	jamoLBase1 = 0x84
+	jamoLEnd   = 0x1113
+	jamoVBase  = 0x1161
+	jamoVEnd   = 0x1176
+	jamoTBase  = 0x11A7
+	jamoTEnd   = 0x11C3
+
+	jamoTCount   = 28
+	jamoVCount   = 21
+	jamoVTCount  = 21 * 28
+	jamoLVTCount = 19 * 21 * 28
+)
+
+const hangulUTF8Size = 3
+
+func isHangul(b []byte) bool {
+	if len(b) < hangulUTF8Size {
+		return false
+	}
+	b0 := b[0]
+	if b0 < hangulBase0 {
+		return false
+	}
+	b1 := b[1]
+	switch {
+	case b0 == hangulBase0:
+		return b1 >= hangulBase1
+	case b0 < hangulEnd0:
+		return true
+	case b0 > hangulEnd0:
+		return false
+	case b1 < hangulEnd1:
+		return true
+	}
+	return b1 == hangulEnd1 && b[2] < hangulEnd2
+}
+
+func isHangulString(b string) bool {
+	if len(b) < hangulUTF8Size {
+		return false
+	}
+	b0 := b[0]
+	if b0 < hangulBase0 {
+		return false
+	}
+	b1 := b[1]
+	switch {
+	case b0 == hangulBase0:
+		return b1 >= hangulBase1
+	case b0 < hangulEnd0:
+		return true
+	case b0 > hangulEnd0:
+		return false
+	case b1 < hangulEnd1:
+		return true
+	}
+	return b1 == hangulEnd1 && b[2] < hangulEnd2
+}
+
+// Caller must ensure len(b) >= 2.
+func isJamoVT(b []byte) bool {
+	// True if (rune & 0xff00) == jamoLBase
+	return b[0] == jamoLBase0 && (b[1]&0xFC) == jamoLBase1
+}
+
+func isHangulWithoutJamoT(b []byte) bool {
+	c, _ := utf8.DecodeRune(b)
+	c -= hangulBase
+	return c < jamoLVTCount && c%jamoTCount == 0
+}
+
+// decomposeHangul writes the decomposed Hangul to buf and returns the number
+// of bytes written.  len(buf) should be at least 9.
+func decomposeHangul(buf []byte, r rune) int {
+	const JamoUTF8Len = 3
+	r -= hangulBase
+	x := r % jamoTCount
+	r /= jamoTCount
+	utf8.EncodeRune(buf, jamoLBase+r/jamoVCount)
+	utf8.EncodeRune(buf[JamoUTF8Len:], jamoVBase+r%jamoVCount)
+	if x != 0 {
+		utf8.EncodeRune(buf[2*JamoUTF8Len:], jamoTBase+x)
+		return 3 * JamoUTF8Len
+	}
+	return 2 * JamoUTF8Len
+}
+
+// decomposeHangul algorithmically decomposes a Hangul rune into
+// its Jamo components.
+// See http://unicode.org/reports/tr15/#Hangul for details on decomposing Hangul.
+func (rb *reorderBuffer) decomposeHangul(r rune) {
+	r -= hangulBase
+	x := r % jamoTCount
+	r /= jamoTCount
+	rb.appendRune(jamoLBase + r/jamoVCount)
+	rb.appendRune(jamoVBase + r%jamoVCount)
+	if x != 0 {
+		rb.appendRune(jamoTBase + x)
+	}
+}
+
+// combineHangul algorithmically combines Jamo character components into Hangul.
+// See http://unicode.org/reports/tr15/#Hangul for details on combining Hangul.
+func (rb *reorderBuffer) combineHangul(s, i, k int) {
+	b := rb.rune[:]
+	bn := rb.nrune
+	for ; i < bn; i++ {
+		cccB := b[k-1].ccc
+		cccC := b[i].ccc
+		if cccB == 0 {
+			s = k - 1
+		}
+		if s != k-1 && cccB >= cccC {
+			// b[i] is blocked by greater-equal cccX below it
+			b[k] = b[i]
+			k++
+		} else {
+			l := rb.runeAt(s) // also used to compare to hangulBase
+			v := rb.runeAt(i) // also used to compare to jamoT
+			switch {
+			case jamoLBase <= l && l < jamoLEnd &&
+				jamoVBase <= v && v < jamoVEnd:
+				// 11xx plus 116x to LV
+				rb.assignRune(s, hangulBase+
+					(l-jamoLBase)*jamoVTCount+(v-jamoVBase)*jamoTCount)
+			case hangulBase <= l && l < hangulEnd &&
+				jamoTBase < v && v < jamoTEnd &&
+				((l-hangulBase)%jamoTCount) == 0:
+				// ACxx plus 11Ax to LVT
+				rb.assignRune(s, l+v-jamoTBase)
+			default:
+				b[k] = b[i]
+				k++
+			}
+		}
+	}
+	rb.nrune = k
+}
+
+// compose recombines the runes in the buffer.
+// It should only be used to recompose a single segment, as it will not
+// handle alternations between Hangul and non-Hangul characters correctly.
+func (rb *reorderBuffer) compose() {
+	// UAX #15, section X5 , including Corrigendum #5
+	// "In any character sequence beginning with starter S, a character C is
+	//  blocked from S if and only if there is some character B between S
+	//  and C, and either B is a starter or it has the same or higher
+	//  combining class as C."
+	bn := rb.nrune
+	if bn == 0 {
+		return
+	}
+	k := 1
+	b := rb.rune[:]
+	for s, i := 0, 1; i < bn; i++ {
+		if isJamoVT(rb.bytesAt(i)) {
+			// Redo from start in Hangul mode. Necessary to support
+			// U+320E..U+321E in NFKC mode.
+			rb.combineHangul(s, i, k)
+			return
+		}
+		ii := b[i]
+		// We can only use combineForward as a filter if we later
+		// get the info for the combined character. This is more
+		// expensive than using the filter. Using combinesBackward()
+		// is safe.
+		if ii.combinesBackward() {
+			cccB := b[k-1].ccc
+			cccC := ii.ccc
+			blocked := false // b[i] blocked by starter or greater or equal CCC?
+			if cccB == 0 {
+				s = k - 1
+			} else {
+				blocked = s != k-1 && cccB >= cccC
+			}
+			if !blocked {
+				combined := combine(rb.runeAt(s), rb.runeAt(i))
+				if combined != 0 {
+					rb.assignRune(s, combined)
+					continue
+				}
+			}
+		}
+		b[k] = b[i]
+		k++
+	}
+	rb.nrune = k
+}

vendor/golang.org/x/text/unicode/norm/forminfo.go

@@ -0,0 +1,259 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package norm
+
+// This file contains Form-specific logic and wrappers for data in tables.go.
+
+// Rune info is stored in a separate trie per composing form. A composing form
+// and its corresponding decomposing form share the same trie.  Each trie maps
+// a rune to a uint16. The values take two forms.  For v >= 0x8000:
+//   bits
+//   15:    1 (inverse of NFD_QC bit of qcInfo)
+//   13..7: qcInfo (see below). isYesD is always true (no decompostion).
+//    6..0: ccc (compressed CCC value).
+// For v < 0x8000, the respective rune has a decomposition and v is an index
+// into a byte array of UTF-8 decomposition sequences and additional info and
+// has the form:
+//    <header> <decomp_byte>* [<tccc> [<lccc>]]
+// The header contains the number of bytes in the decomposition (excluding this
+// length byte). The two most significant bits of this length byte correspond
+// to bit 5 and 4 of qcInfo (see below).  The byte sequence itself starts at v+1.
+// The byte sequence is followed by a trailing and leading CCC if the values
+// for these are not zero.  The value of v determines which ccc are appended
+// to the sequences.  For v < firstCCC, there are none, for v >= firstCCC,
+// the sequence is followed by a trailing ccc, and for v >= firstLeadingCC
+// there is an additional leading ccc. The value of tccc itself is the
+// trailing CCC shifted left 2 bits. The two least-significant bits of tccc
+// are the number of trailing non-starters.
+
+const (
+	qcInfoMask      = 0x3F // to clear all but the relevant bits in a qcInfo
+	headerLenMask   = 0x3F // extract the length value from the header byte
+	headerFlagsMask = 0xC0 // extract the qcInfo bits from the header byte
+)
+
+// Properties provides access to normalization properties of a rune.
+type Properties struct {
+	pos   uint8  // start position in reorderBuffer; used in composition.go
+	size  uint8  // length of UTF-8 encoding of this rune
+	ccc   uint8  // leading canonical combining class (ccc if not decomposition)
+	tccc  uint8  // trailing canonical combining class (ccc if not decomposition)
+	nLead uint8  // number of leading non-starters.
+	flags qcInfo // quick check flags
+	index uint16
+}
+
+// functions dispatchable per form
+type lookupFunc func(b input, i int) Properties
+
+// formInfo holds Form-specific functions and tables.
+type formInfo struct {
+	form                     Form
+	composing, compatibility bool // form type
+	info                     lookupFunc
+	nextMain                 iterFunc
+}
+
+var formTable = []*formInfo{{
+	form:          NFC,
+	composing:     true,
+	compatibility: false,
+	info:          lookupInfoNFC,
+	nextMain:      nextComposed,
+}, {
+	form:          NFD,
+	composing:     false,
+	compatibility: false,
+	info:          lookupInfoNFC,
+	nextMain:      nextDecomposed,
+}, {
+	form:          NFKC,
+	composing:     true,
+	compatibility: true,
+	info:          lookupInfoNFKC,
+	nextMain:      nextComposed,
+}, {
+	form:          NFKD,
+	composing:     false,
+	compatibility: true,
+	info:          lookupInfoNFKC,
+	nextMain:      nextDecomposed,
+}}
+
+// We do not distinguish between boundaries for NFC, NFD, etc. to avoid
+// unexpected behavior for the user.  For example, in NFD, there is a boundary
+// after 'a'.  However, 'a' might combine with modifiers, so from the application's
+// perspective it is not a good boundary. We will therefore always use the
+// boundaries for the combining variants.
+
+// BoundaryBefore returns true if this rune starts a new segment and
+// cannot combine with any rune on the left.
+func (p Properties) BoundaryBefore() bool {
+	if p.ccc == 0 && !p.combinesBackward() {
+		return true
+	}
+	// We assume that the CCC of the first character in a decomposition
+	// is always non-zero if different from info.ccc and that we can return
+	// false at this point. This is verified by maketables.
+	return false
+}
+
+// BoundaryAfter returns true if runes cannot combine with or otherwise
+// interact with this or previous runes.
+func (p Properties) BoundaryAfter() bool {
+	// TODO: loosen these conditions.
+	return p.isInert()
+}
+
+// We pack quick check data in 4 bits:
+//   5:    Combines forward  (0 == false, 1 == true)
+//   4..3: NFC_QC Yes(00), No (10), or Maybe (11)
+//   2:    NFD_QC Yes (0) or No (1). No also means there is a decomposition.
+//   1..0: Number of trailing non-starters.
+//
+// When all 4 bits are zero, the character is inert, meaning it is never
+// influenced by normalization.
+type qcInfo uint8
+
+func (p Properties) isYesC() bool { return p.flags&0x10 == 0 }
+func (p Properties) isYesD() bool { return p.flags&0x4 == 0 }
+
+func (p Properties) combinesForward() bool  { return p.flags&0x20 != 0 }
+func (p Properties) combinesBackward() bool { return p.flags&0x8 != 0 } // == isMaybe
+func (p Properties) hasDecomposition() bool { return p.flags&0x4 != 0 } // == isNoD
+
+func (p Properties) isInert() bool {
+	return p.flags&qcInfoMask == 0 && p.ccc == 0
+}
+
+func (p Properties) multiSegment() bool {
+	return p.index >= firstMulti && p.index < endMulti
+}
+
+func (p Properties) nLeadingNonStarters() uint8 {
+	return p.nLead
+}
+
+func (p Properties) nTrailingNonStarters() uint8 {
+	return uint8(p.flags & 0x03)
+}
+
+// Decomposition returns the decomposition for the underlying rune
+// or nil if there is none.
+func (p Properties) Decomposition() []byte {
+	// TODO: create the decomposition for Hangul?
+	if p.index == 0 {
+		return nil
+	}
+	i := p.index
+	n := decomps[i] & headerLenMask
+	i++
+	return decomps[i : i+uint16(n)]
+}
+
+// Size returns the length of UTF-8 encoding of the rune.
+func (p Properties) Size() int {
+	return int(p.size)
+}
+
+// CCC returns the canonical combining class of the underlying rune.
+func (p Properties) CCC() uint8 {
+	if p.index >= firstCCCZeroExcept {
+		return 0
+	}
+	return ccc[p.ccc]
+}
+
+// LeadCCC returns the CCC of the first rune in the decomposition.
+// If there is no decomposition, LeadCCC equals CCC.
+func (p Properties) LeadCCC() uint8 {
+	return ccc[p.ccc]
+}
+
+// TrailCCC returns the CCC of the last rune in the decomposition.
+// If there is no decomposition, TrailCCC equals CCC.
+func (p Properties) TrailCCC() uint8 {
+	return ccc[p.tccc]
+}
+
+// Recomposition
+// We use 32-bit keys instead of 64-bit for the two codepoint keys.
+// This clips off the bits of three entries, but we know this will not
+// result in a collision. In the unlikely event that changes to
+// UnicodeData.txt introduce collisions, the compiler will catch it.
+// Note that the recomposition map for NFC and NFKC are identical.
+
+// combine returns the combined rune or 0 if it doesn't exist.
+func combine(a, b rune) rune {
+	key := uint32(uint16(a))<<16 + uint32(uint16(b))
+	return recompMap[key]
+}
+
+func lookupInfoNFC(b input, i int) Properties {
+	v, sz := b.charinfoNFC(i)
+	return compInfo(v, sz)
+}
+
+func lookupInfoNFKC(b input, i int) Properties {
+	v, sz := b.charinfoNFKC(i)
+	return compInfo(v, sz)
+}
+
+// Properties returns properties for the first rune in s.
+func (f Form) Properties(s []byte) Properties {
+	if f == NFC || f == NFD {
+		return compInfo(nfcData.lookup(s))
+	}
+	return compInfo(nfkcData.lookup(s))
+}
+
+// PropertiesString returns properties for the first rune in s.
+func (f Form) PropertiesString(s string) Properties {
+	if f == NFC || f == NFD {
+		return compInfo(nfcData.lookupString(s))
+	}
+	return compInfo(nfkcData.lookupString(s))
+}
+
+// compInfo converts the information contained in v and sz
+// to a Properties.  See the comment at the top of the file
+// for more information on the format.
+func compInfo(v uint16, sz int) Properties {
+	if v == 0 {
+		return Properties{size: uint8(sz)}
+	} else if v >= 0x8000 {
+		p := Properties{
+			size:  uint8(sz),
+			ccc:   uint8(v),
+			tccc:  uint8(v),
+			flags: qcInfo(v >> 8),
+		}
+		if p.ccc > 0 || p.combinesBackward() {
+			p.nLead = uint8(p.flags & 0x3)
+		}
+		return p
+	}
+	// has decomposition
+	h := decomps[v]
+	f := (qcInfo(h&headerFlagsMask) >> 2) | 0x4
+	p := Properties{size: uint8(sz), flags: f, index: v}
+	if v >= firstCCC {
+		v += uint16(h&headerLenMask) + 1
+		c := decomps[v]
+		p.tccc = c >> 2
+		p.flags |= qcInfo(c & 0x3)
+		if v >= firstLeadingCCC {
+			p.nLead = c & 0x3
+			if v >= firstStarterWithNLead {
+				// We were tricked. Remove the decomposition.
+				p.flags &= 0x03
+				p.index = 0
+				return p
+			}
+			p.ccc = decomps[v+1]
+		}
+	}
+	return p
+}

vendor/golang.org/x/text/unicode/norm/input.go

@@ -0,0 +1,105 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package norm
+
+import "unicode/utf8"
+
+type input struct {
+	str   string
+	bytes []byte
+}
+
+func inputBytes(str []byte) input {
+	return input{bytes: str}
+}
+
+func inputString(str string) input {
+	return input{str: str}
+}
+
+func (in *input) setBytes(str []byte) {
+	in.str = ""
+	in.bytes = str
+}
+
+func (in *input) setString(str string) {
+	in.str = str
+	in.bytes = nil
+}
+
+func (in *input) _byte(p int) byte {
+	if in.bytes == nil {
+		return in.str[p]
+	}
+	return in.bytes[p]
+}
+
+func (in *input) skipASCII(p, max int) int {
+	if in.bytes == nil {
+		for ; p < max && in.str[p] < utf8.RuneSelf; p++ {
+		}
+	} else {
+		for ; p < max && in.bytes[p] < utf8.RuneSelf; p++ {
+		}
+	}
+	return p
+}
+
+func (in *input) skipContinuationBytes(p int) int {
+	if in.bytes == nil {
+		for ; p < len(in.str) && !utf8.RuneStart(in.str[p]); p++ {
+		}
+	} else {
+		for ; p < len(in.bytes) && !utf8.RuneStart(in.bytes[p]); p++ {
+		}
+	}
+	return p
+}
+
+func (in *input) appendSlice(buf []byte, b, e int) []byte {
+	if in.bytes != nil {
+		return append(buf, in.bytes[b:e]...)
+	}
+	for i := b; i < e; i++ {
+		buf = append(buf, in.str[i])
+	}
+	return buf
+}
+
+func (in *input) copySlice(buf []byte, b, e int) int {
+	if in.bytes == nil {
+		return copy(buf, in.str[b:e])
+	}
+	return copy(buf, in.bytes[b:e])
+}
+
+func (in *input) charinfoNFC(p int) (uint16, int) {
+	if in.bytes == nil {
+		return nfcData.lookupString(in.str[p:])
+	}
+	return nfcData.lookup(in.bytes[p:])
+}
+
+func (in *input) charinfoNFKC(p int) (uint16, int) {
+	if in.bytes == nil {
+		return nfkcData.lookupString(in.str[p:])
+	}
+	return nfkcData.lookup(in.bytes[p:])
+}
+
+func (in *input) hangul(p int) (r rune) {
+	if in.bytes == nil {
+		if !isHangulString(in.str[p:]) {
+			return 0
+		}
+		r, _ = utf8.DecodeRuneInString(in.str[p:])
+	} else {
+		if !isHangul(in.bytes[p:]) {
+			return 0
+		}
+		r, _ = utf8.DecodeRune(in.bytes[p:])
+	}
+	return r
+}

vendor/golang.org/x/text/unicode/norm/iter.go

@@ -0,0 +1,450 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package norm
+
+import (
+	"fmt"
+	"unicode/utf8"
+)
+
+// MaxSegmentSize is the maximum size of a byte buffer needed to consider any
+// sequence of starter and non-starter runes for the purpose of normalization.
+const MaxSegmentSize = maxByteBufferSize
+
+// An Iter iterates over a string or byte slice, while normalizing it
+// to a given Form.
+type Iter struct {
+	rb     reorderBuffer
+	buf    [maxByteBufferSize]byte
+	info   Properties // first character saved from previous iteration
+	next   iterFunc   // implementation of next depends on form
+	asciiF iterFunc
+
+	p        int    // current position in input source
+	multiSeg []byte // remainder of multi-segment decomposition
+}
+
+type iterFunc func(*Iter) []byte
+
+// Init initializes i to iterate over src after normalizing it to Form f.
+func (i *Iter) Init(f Form, src []byte) {
+	i.p = 0
+	if len(src) == 0 {
+		i.setDone()
+		i.rb.nsrc = 0
+		return
+	}
+	i.multiSeg = nil
+	i.rb.init(f, src)
+	i.next = i.rb.f.nextMain
+	i.asciiF = nextASCIIBytes
+	i.info = i.rb.f.info(i.rb.src, i.p)
+}
+
+// InitString initializes i to iterate over src after normalizing it to Form f.
+func (i *Iter) InitString(f Form, src string) {
+	i.p = 0
+	if len(src) == 0 {
+		i.setDone()
+		i.rb.nsrc = 0
+		return
+	}
+	i.multiSeg = nil
+	i.rb.initString(f, src)
+	i.next = i.rb.f.nextMain
+	i.asciiF = nextASCIIString
+	i.info = i.rb.f.info(i.rb.src, i.p)
+}
+
+// Seek sets the segment to be returned by the next call to Next to start
+// at position p.  It is the responsibility of the caller to set p to the
+// start of a UTF8 rune.
+func (i *Iter) Seek(offset int64, whence int) (int64, error) {
+	var abs int64
+	switch whence {
+	case 0:
+		abs = offset
+	case 1:
+		abs = int64(i.p) + offset
+	case 2:
+		abs = int64(i.rb.nsrc) + offset
+	default:
+		return 0, fmt.Errorf("norm: invalid whence")
+	}
+	if abs < 0 {
+		return 0, fmt.Errorf("norm: negative position")
+	}
+	if int(abs) >= i.rb.nsrc {
+		i.setDone()
+		return int64(i.p), nil
+	}
+	i.p = int(abs)
+	i.multiSeg = nil
+	i.next = i.rb.f.nextMain
+	i.info = i.rb.f.info(i.rb.src, i.p)
+	return abs, nil
+}
+
+// returnSlice returns a slice of the underlying input type as a byte slice.
+// If the underlying is of type []byte, it will simply return a slice.
+// If the underlying is of type string, it will copy the slice to the buffer
+// and return that.
+func (i *Iter) returnSlice(a, b int) []byte {
+	if i.rb.src.bytes == nil {
+		return i.buf[:copy(i.buf[:], i.rb.src.str[a:b])]
+	}
+	return i.rb.src.bytes[a:b]
+}
+
+// Pos returns the byte position at which the next call to Next will commence processing.
+func (i *Iter) Pos() int {
+	return i.p
+}
+
+func (i *Iter) setDone() {
+	i.next = nextDone
+	i.p = i.rb.nsrc
+}
+
+// Done returns true if there is no more input to process.
+func (i *Iter) Done() bool {
+	return i.p >= i.rb.nsrc
+}
+
+// Next returns f(i.input[i.Pos():n]), where n is a boundary of i.input.
+// For any input a and b for which f(a) == f(b), subsequent calls
+// to Next will return the same segments.
+// Modifying runes are grouped together with the preceding starter, if such a starter exists.
+// Although not guaranteed, n will typically be the smallest possible n.
+func (i *Iter) Next() []byte {
+	return i.next(i)
+}
+
+func nextASCIIBytes(i *Iter) []byte {
+	p := i.p + 1
+	if p >= i.rb.nsrc {
+		i.setDone()
+		return i.rb.src.bytes[i.p:p]
+	}
+	if i.rb.src.bytes[p] < utf8.RuneSelf {
+		p0 := i.p
+		i.p = p
+		return i.rb.src.bytes[p0:p]
+	}
+	i.info = i.rb.f.info(i.rb.src, i.p)
+	i.next = i.rb.f.nextMain
+	return i.next(i)
+}
+
+func nextASCIIString(i *Iter) []byte {
+	p := i.p + 1
+	if p >= i.rb.nsrc {
+		i.buf[0] = i.rb.src.str[i.p]
+		i.setDone()
+		return i.buf[:1]
+	}
+	if i.rb.src.str[p] < utf8.RuneSelf {
+		i.buf[0] = i.rb.src.str[i.p]
+		i.p = p
+		return i.buf[:1]
+	}
+	i.info = i.rb.f.info(i.rb.src, i.p)
+	i.next = i.rb.f.nextMain
+	return i.next(i)
+}
+
+func nextHangul(i *Iter) []byte {
+	p := i.p
+	next := p + hangulUTF8Size
+	if next >= i.rb.nsrc {
+		i.setDone()
+	} else if i.rb.src.hangul(next) == 0 {
+		i.info = i.rb.f.info(i.rb.src, i.p)
+		i.next = i.rb.f.nextMain
+		return i.next(i)
+	}
+	i.p = next
+	return i.buf[:decomposeHangul(i.buf[:], i.rb.src.hangul(p))]
+}
+
+func nextDone(i *Iter) []byte {
+	return nil
+}
+
+// nextMulti is used for iterating over multi-segment decompositions
+// for decomposing normal forms.
+func nextMulti(i *Iter) []byte {
+	j := 0
+	d := i.multiSeg
+	// skip first rune
+	for j = 1; j < len(d) && !utf8.RuneStart(d[j]); j++ {
+	}
+	for j < len(d) {
+		info := i.rb.f.info(input{bytes: d}, j)
+		if info.BoundaryBefore() {
+			i.multiSeg = d[j:]
+			return d[:j]
+		}
+		j += int(info.size)
+	}
+	// treat last segment as normal decomposition
+	i.next = i.rb.f.nextMain
+	return i.next(i)
+}
+
+// nextMultiNorm is used for iterating over multi-segment decompositions
+// for composing normal forms.
+func nextMultiNorm(i *Iter) []byte {
+	j := 0
+	d := i.multiSeg
+	for j < len(d) {
+		info := i.rb.f.info(input{bytes: d}, j)
+		if info.BoundaryBefore() {
+			i.rb.compose()
+			seg := i.buf[:i.rb.flushCopy(i.buf[:])]
+			i.rb.ss.first(info)
+			i.rb.insertUnsafe(input{bytes: d}, j, info)
+			i.multiSeg = d[j+int(info.size):]
+			return seg
+		}
+		i.rb.ss.next(info)
+		i.rb.insertUnsafe(input{bytes: d}, j, info)
+		j += int(info.size)
+	}
+	i.multiSeg = nil
+	i.next = nextComposed
+	return doNormComposed(i)
+}
+
+// nextDecomposed is the implementation of Next for forms NFD and NFKD.
+func nextDecomposed(i *Iter) (next []byte) {
+	outp := 0
+	inCopyStart, outCopyStart := i.p, 0
+	ss := mkStreamSafe(i.info)
+	for {
+		if sz := int(i.info.size); sz <= 1 {
+			p := i.p
+			i.p++ // ASCII or illegal byte.  Either way, advance by 1.
+			if i.p >= i.rb.nsrc {
+				i.setDone()
+				return i.returnSlice(p, i.p)
+			} else if i.rb.src._byte(i.p) < utf8.RuneSelf {
+				i.next = i.asciiF
+				return i.returnSlice(p, i.p)
+			}
+			outp++
+		} else if d := i.info.Decomposition(); d != nil {
+			// Note: If leading CCC != 0, then len(d) == 2 and last is also non-zero.
+			// Case 1: there is a leftover to copy.  In this case the decomposition
+			// must begin with a modifier and should always be appended.
+			// Case 2: no leftover. Simply return d if followed by a ccc == 0 value.
+			p := outp + len(d)
+			if outp > 0 {
+				i.rb.src.copySlice(i.buf[outCopyStart:], inCopyStart, i.p)
+				if p > len(i.buf) {
+					return i.buf[:outp]
+				}
+			} else if i.info.multiSegment() {
+				// outp must be 0 as multi-segment decompositions always
+				// start a new segment.
+				if i.multiSeg == nil {
+					i.multiSeg = d
+					i.next = nextMulti
+					return nextMulti(i)
+				}
+				// We are in the last segment.  Treat as normal decomposition.
+				d = i.multiSeg
+				i.multiSeg = nil
+				p = len(d)
+			}
+			prevCC := i.info.tccc
+			if i.p += sz; i.p >= i.rb.nsrc {
+				i.setDone()
+				i.info = Properties{} // Force BoundaryBefore to succeed.
+			} else {
+				i.info = i.rb.f.info(i.rb.src, i.p)
+			}
+			switch ss.next(i.info) {
+			case ssOverflow:
+				i.next = nextCGJDecompose
+				fallthrough
+			case ssStarter:
+				if outp > 0 {
+					copy(i.buf[outp:], d)
+					return i.buf[:p]
+				}
+				return d
+			}
+			copy(i.buf[outp:], d)
+			outp = p
+			inCopyStart, outCopyStart = i.p, outp
+			if i.info.ccc < prevCC {
+				goto doNorm
+			}
+			continue
+		} else if r := i.rb.src.hangul(i.p); r != 0 {
+			outp = decomposeHangul(i.buf[:], r)
+			i.p += hangulUTF8Size
+			inCopyStart, outCopyStart = i.p, outp
+			if i.p >= i.rb.nsrc {
+				i.setDone()
+				break
+			} else if i.rb.src.hangul(i.p) != 0 {
+				i.next = nextHangul
+				return i.buf[:outp]
+			}
+		} else {
+			p := outp + sz
+			if p > len(i.buf) {
+				break
+			}
+			outp = p
+			i.p += sz
+		}
+		if i.p >= i.rb.nsrc {
+			i.setDone()
+			break
+		}
+		prevCC := i.info.tccc
+		i.info = i.rb.f.info(i.rb.src, i.p)
+		if v := ss.next(i.info); v == ssStarter {
+			break
+		} else if v == ssOverflow {
+			i.next = nextCGJDecompose
+			break
+		}
+		if i.info.ccc < prevCC {
+			goto doNorm
+		}
+	}
+	if outCopyStart == 0 {
+		return i.returnSlice(inCopyStart, i.p)
+	} else if inCopyStart < i.p {
+		i.rb.src.copySlice(i.buf[outCopyStart:], inCopyStart, i.p)
+	}
+	return i.buf[:outp]
+doNorm:
+	// Insert what we have decomposed so far in the reorderBuffer.
+	// As we will only reorder, there will always be enough room.
+	i.rb.src.copySlice(i.buf[outCopyStart:], inCopyStart, i.p)
+	i.rb.insertDecomposed(i.buf[0:outp])
+	return doNormDecomposed(i)
+}
+
+func doNormDecomposed(i *Iter) []byte {
+	for {
+		if s := i.rb.ss.next(i.info); s == ssOverflow {
+			i.next = nextCGJDecompose
+			break
+		}
+		i.rb.insertUnsafe(i.rb.src, i.p, i.info)
+		if i.p += int(i.info.size); i.p >= i.rb.nsrc {
+			i.setDone()
+			break
+		}
+		i.info = i.rb.f.info(i.rb.src, i.p)
+		if i.info.ccc == 0 {
+			break
+		}
+	}
+	// new segment or too many combining characters: exit normalization
+	return i.buf[:i.rb.flushCopy(i.buf[:])]
+}
+
+func nextCGJDecompose(i *Iter) []byte {
+	i.rb.ss = 0
+	i.rb.insertCGJ()
+	i.next = nextDecomposed
+	buf := doNormDecomposed(i)
+	return buf
+}
+
+// nextComposed is the implementation of Next for forms NFC and NFKC.
+func nextComposed(i *Iter) []byte {
+	outp, startp := 0, i.p
+	var prevCC uint8
+	ss := mkStreamSafe(i.info)
+	for {
+		if !i.info.isYesC() {
+			goto doNorm
+		}
+		prevCC = i.info.tccc
+		sz := int(i.info.size)
+		if sz == 0 {
+			sz = 1 // illegal rune: copy byte-by-byte
+		}
+		p := outp + sz
+		if p > len(i.buf) {
+			break
+		}
+		outp = p
+		i.p += sz
+		if i.p >= i.rb.nsrc {
+			i.setDone()
+			break
+		} else if i.rb.src._byte(i.p) < utf8.RuneSelf {
+			i.next = i.asciiF
+			break
+		}
+		i.info = i.rb.f.info(i.rb.src, i.p)
+		if v := ss.next(i.info); v == ssStarter {
+			break
+		} else if v == ssOverflow {
+			i.next = nextCGJCompose
+			break
+		}
+		if i.info.ccc < prevCC {
+			goto doNorm
+		}
+	}
+	return i.returnSlice(startp, i.p)
+doNorm:
+	i.p = startp
+	i.info = i.rb.f.info(i.rb.src, i.p)
+	if i.info.multiSegment() {
+		d := i.info.Decomposition()
+		info := i.rb.f.info(input{bytes: d}, 0)
+		i.rb.insertUnsafe(input{bytes: d}, 0, info)
+		i.multiSeg = d[int(info.size):]
+		i.next = nextMultiNorm
+		return nextMultiNorm(i)
+	}
+	i.rb.ss.first(i.info)
+	i.rb.insertUnsafe(i.rb.src, i.p, i.info)
+	return doNormComposed(i)
+}
+
+func doNormComposed(i *Iter) []byte {
+	// First rune should already be inserted.
+	for {
+		if i.p += int(i.info.size); i.p >= i.rb.nsrc {
+			i.setDone()
+			break
+		}
+		i.info = i.rb.f.info(i.rb.src, i.p)
+		if s := i.rb.ss.next(i.info); s == ssStarter {
+			break
+		} else if s == ssOverflow {
+			i.next = nextCGJCompose
+			break
+		}
+		i.rb.insertUnsafe(i.rb.src, i.p, i.info)
+	}
+	i.rb.compose()
+	seg := i.buf[:i.rb.flushCopy(i.buf[:])]
+	return seg
+}
+
+func nextCGJCompose(i *Iter) []byte {
+	i.rb.ss = 0 // instead of first
+	i.rb.insertCGJ()
+	i.next = nextComposed
+	// Note that we treat any rune with nLeadingNonStarters > 0 as a non-starter,
+	// even if they are not. This is particularly dubious for U+FF9E and UFF9A.
+	// If we ever change that, insert a check here.
+	i.rb.ss.first(i.info)
+	i.rb.insertUnsafe(i.rb.src, i.p, i.info)
+	return doNormComposed(i)
+}

vendor/golang.org/x/text/unicode/norm/maketables.go

@@ -0,0 +1,976 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+
+// Normalization table generator.
+// Data read from the web.
+// See forminfo.go for a description of the trie values associated with each rune.
+
+package main
+
+import (
+	"bytes"
+	"flag"
+	"fmt"
+	"io"
+	"log"
+	"sort"
+	"strconv"
+	"strings"
+
+	"golang.org/x/text/internal/gen"
+	"golang.org/x/text/internal/triegen"
+	"golang.org/x/text/internal/ucd"
+)
+
+func main() {
+	gen.Init()
+	loadUnicodeData()
+	compactCCC()
+	loadCompositionExclusions()
+	completeCharFields(FCanonical)
+	completeCharFields(FCompatibility)
+	computeNonStarterCounts()
+	verifyComputed()
+	printChars()
+	testDerived()
+	printTestdata()
+	makeTables()
+}
+
+var (
+	tablelist = flag.String("tables",
+		"all",
+		"comma-separated list of which tables to generate; "+
+			"can be 'decomp', 'recomp', 'info' and 'all'")
+	test = flag.Bool("test",
+		false,
+		"test existing tables against DerivedNormalizationProps and generate test data for regression testing")
+	verbose = flag.Bool("verbose",
+		false,
+		"write data to stdout as it is parsed")
+)
+
+const MaxChar = 0x10FFFF // anything above this shouldn't exist
+
+// Quick Check properties of runes allow us to quickly
+// determine whether a rune may occur in a normal form.
+// For a given normal form, a rune may be guaranteed to occur
+// verbatim (QC=Yes), may or may not combine with another
+// rune (QC=Maybe), or may not occur (QC=No).
+type QCResult int
+
+const (
+	QCUnknown QCResult = iota
+	QCYes
+	QCNo
+	QCMaybe
+)
+
+func (r QCResult) String() string {
+	switch r {
+	case QCYes:
+		return "Yes"
+	case QCNo:
+		return "No"
+	case QCMaybe:
+		return "Maybe"
+	}
+	return "***UNKNOWN***"
+}
+
+const (
+	FCanonical     = iota // NFC or NFD
+	FCompatibility        // NFKC or NFKD
+	FNumberOfFormTypes
+)
+
+const (
+	MComposed   = iota // NFC or NFKC
+	MDecomposed        // NFD or NFKD
+	MNumberOfModes
+)
+
+// This contains only the properties we're interested in.
+type Char struct {
+	name          string
+	codePoint     rune  // if zero, this index is not a valid code point.
+	ccc           uint8 // canonical combining class
+	origCCC       uint8
+	excludeInComp bool // from CompositionExclusions.txt
+	compatDecomp  bool // it has a compatibility expansion
+
+	nTrailingNonStarters uint8
+	nLeadingNonStarters  uint8 // must be equal to trailing if non-zero
+
+	forms [FNumberOfFormTypes]FormInfo // For FCanonical and FCompatibility
+
+	state State
+}
+
+var chars = make([]Char, MaxChar+1)
+var cccMap = make(map[uint8]uint8)
+
+func (c Char) String() string {
+	buf := new(bytes.Buffer)
+
+	fmt.Fprintf(buf, "%U [%s]:\n", c.codePoint, c.name)
+	fmt.Fprintf(buf, "  ccc: %v\n", c.ccc)
+	fmt.Fprintf(buf, "  excludeInComp: %v\n", c.excludeInComp)
+	fmt.Fprintf(buf, "  compatDecomp: %v\n", c.compatDecomp)
+	fmt.Fprintf(buf, "  state: %v\n", c.state)
+	fmt.Fprintf(buf, "  NFC:\n")
+	fmt.Fprint(buf, c.forms[FCanonical])
+	fmt.Fprintf(buf, "  NFKC:\n")
+	fmt.Fprint(buf, c.forms[FCompatibility])
+
+	return buf.String()
+}
+
+// In UnicodeData.txt, some ranges are marked like this:
+//	3400;<CJK Ideograph Extension A, First>;Lo;0;L;;;;;N;;;;;
+//	4DB5;<CJK Ideograph Extension A, Last>;Lo;0;L;;;;;N;;;;;
+// parseCharacter keeps a state variable indicating the weirdness.
+type State int
+
+const (
+	SNormal State = iota // known to be zero for the type
+	SFirst
+	SLast
+	SMissing
+)
+
+var lastChar = rune('\u0000')
+
+func (c Char) isValid() bool {
+	return c.codePoint != 0 && c.state != SMissing
+}
+
+type FormInfo struct {
+	quickCheck [MNumberOfModes]QCResult // index: MComposed or MDecomposed
+	verified   [MNumberOfModes]bool     // index: MComposed or MDecomposed
+
+	combinesForward  bool // May combine with rune on the right
+	combinesBackward bool // May combine with rune on the left
+	isOneWay         bool // Never appears in result
+	inDecomp         bool // Some decompositions result in this char.
+	decomp           Decomposition
+	expandedDecomp   Decomposition
+}
+
+func (f FormInfo) String() string {
+	buf := bytes.NewBuffer(make([]byte, 0))
+
+	fmt.Fprintf(buf, "    quickCheck[C]: %v\n", f.quickCheck[MComposed])
+	fmt.Fprintf(buf, "    quickCheck[D]: %v\n", f.quickCheck[MDecomposed])
+	fmt.Fprintf(buf, "    cmbForward: %v\n", f.combinesForward)
+	fmt.Fprintf(buf, "    cmbBackward: %v\n", f.combinesBackward)
+	fmt.Fprintf(buf, "    isOneWay: %v\n", f.isOneWay)
+	fmt.Fprintf(buf, "    inDecomp: %v\n", f.inDecomp)
+	fmt.Fprintf(buf, "    decomposition: %X\n", f.decomp)
+	fmt.Fprintf(buf, "    expandedDecomp: %X\n", f.expandedDecomp)
+
+	return buf.String()
+}
+
+type Decomposition []rune
+
+func parseDecomposition(s string, skipfirst bool) (a []rune, err error) {
+	decomp := strings.Split(s, " ")
+	if len(decomp) > 0 && skipfirst {
+		decomp = decomp[1:]
+	}
+	for _, d := range decomp {
+		point, err := strconv.ParseUint(d, 16, 64)
+		if err != nil {
+			return a, err
+		}
+		a = append(a, rune(point))
+	}
+	return a, nil
+}
+
+func loadUnicodeData() {
+	f := gen.OpenUCDFile("UnicodeData.txt")
+	defer f.Close()
+	p := ucd.New(f)
+	for p.Next() {
+		r := p.Rune(ucd.CodePoint)
+		char := &chars[r]
+
+		char.ccc = uint8(p.Uint(ucd.CanonicalCombiningClass))
+		decmap := p.String(ucd.DecompMapping)
+
+		exp, err := parseDecomposition(decmap, false)
+		isCompat := false
+		if err != nil {
+			if len(decmap) > 0 {
+				exp, err = parseDecomposition(decmap, true)
+				if err != nil {
+					log.Fatalf(`%U: bad decomp |%v|: "%s"`, r, decmap, err)
+				}
+				isCompat = true
+			}
+		}
+
+		char.name = p.String(ucd.Name)
+		char.codePoint = r
+		char.forms[FCompatibility].decomp = exp
+		if !isCompat {
+			char.forms[FCanonical].decomp = exp
+		} else {
+			char.compatDecomp = true
+		}
+		if len(decmap) > 0 {
+			char.forms[FCompatibility].decomp = exp
+		}
+	}
+	if err := p.Err(); err != nil {
+		log.Fatal(err)
+	}
+}
+
+// compactCCC converts the sparse set of CCC values to a continguous one,
+// reducing the number of bits needed from 8 to 6.
+func compactCCC() {
+	m := make(map[uint8]uint8)
+	for i := range chars {
+		c := &chars[i]
+		m[c.ccc] = 0
+	}
+	cccs := []int{}
+	for v, _ := range m {
+		cccs = append(cccs, int(v))
+	}
+	sort.Ints(cccs)
+	for i, c := range cccs {
+		cccMap[uint8(i)] = uint8(c)
+		m[uint8(c)] = uint8(i)
+	}
+	for i := range chars {
+		c := &chars[i]
+		c.origCCC = c.ccc
+		c.ccc = m[c.ccc]
+	}
+	if len(m) >= 1<<6 {
+		log.Fatalf("too many difference CCC values: %d >= 64", len(m))
+	}
+}
+
+// CompositionExclusions.txt has form:
+// 0958    # ...
+// See http://unicode.org/reports/tr44/ for full explanation
+func loadCompositionExclusions() {
+	f := gen.OpenUCDFile("CompositionExclusions.txt")
+	defer f.Close()
+	p := ucd.New(f)
+	for p.Next() {
+		c := &chars[p.Rune(0)]
+		if c.excludeInComp {
+			log.Fatalf("%U: Duplicate entry in exclusions.", c.codePoint)
+		}
+		c.excludeInComp = true
+	}
+	if e := p.Err(); e != nil {
+		log.Fatal(e)
+	}
+}
+
+// hasCompatDecomp returns true if any of the recursive
+// decompositions contains a compatibility expansion.
+// In this case, the character may not occur in NFK*.
+func hasCompatDecomp(r rune) bool {
+	c := &chars[r]
+	if c.compatDecomp {
+		return true
+	}
+	for _, d := range c.forms[FCompatibility].decomp {
+		if hasCompatDecomp(d) {
+			return true
+		}
+	}
+	return false
+}
+
+// Hangul related constants.
+const (
+	HangulBase = 0xAC00
+	HangulEnd  = 0xD7A4 // hangulBase + Jamo combinations (19 * 21 * 28)
+
+	JamoLBase = 0x1100
+	JamoLEnd  = 0x1113
+	JamoVBase = 0x1161
+	JamoVEnd  = 0x1176
+	JamoTBase = 0x11A8
+	JamoTEnd  = 0x11C3
+
+	JamoLVTCount = 19 * 21 * 28
+	JamoTCount   = 28
+)
+
+func isHangul(r rune) bool {
+	return HangulBase <= r && r < HangulEnd
+}
+
+func isHangulWithoutJamoT(r rune) bool {
+	if !isHangul(r) {
+		return false
+	}
+	r -= HangulBase
+	return r < JamoLVTCount && r%JamoTCount == 0
+}
+
+func ccc(r rune) uint8 {
+	return chars[r].ccc
+}
+
+// Insert a rune in a buffer, ordered by Canonical Combining Class.
+func insertOrdered(b Decomposition, r rune) Decomposition {
+	n := len(b)
+	b = append(b, 0)
+	cc := ccc(r)
+	if cc > 0 {
+		// Use bubble sort.
+		for ; n > 0; n-- {
+			if ccc(b[n-1]) <= cc {
+				break
+			}
+			b[n] = b[n-1]
+		}
+	}
+	b[n] = r
+	return b
+}
+
+// Recursively decompose.
+func decomposeRecursive(form int, r rune, d Decomposition) Decomposition {
+	dcomp := chars[r].forms[form].decomp
+	if len(dcomp) == 0 {
+		return insertOrdered(d, r)
+	}
+	for _, c := range dcomp {
+		d = decomposeRecursive(form, c, d)
+	}
+	return d
+}
+
+func completeCharFields(form int) {
+	// Phase 0: pre-expand decomposition.
+	for i := range chars {
+		f := &chars[i].forms[form]
+		if len(f.decomp) == 0 {
+			continue
+		}
+		exp := make(Decomposition, 0)
+		for _, c := range f.decomp {
+			exp = decomposeRecursive(form, c, exp)
+		}
+		f.expandedDecomp = exp
+	}
+
+	// Phase 1: composition exclusion, mark decomposition.
+	for i := range chars {
+		c := &chars[i]
+		f := &c.forms[form]
+
+		// Marks script-specific exclusions and version restricted.
+		f.isOneWay = c.excludeInComp
+
+		// Singletons
+		f.isOneWay = f.isOneWay || len(f.decomp) == 1
+
+		// Non-starter decompositions
+		if len(f.decomp) > 1 {
+			chk := c.ccc != 0 || chars[f.decomp[0]].ccc != 0
+			f.isOneWay = f.isOneWay || chk
+		}
+
+		// Runes that decompose into more than two runes.
+		f.isOneWay = f.isOneWay || len(f.decomp) > 2
+
+		if form == FCompatibility {
+			f.isOneWay = f.isOneWay || hasCompatDecomp(c.codePoint)
+		}
+
+		for _, r := range f.decomp {
+			chars[r].forms[form].inDecomp = true
+		}
+	}
+
+	// Phase 2: forward and backward combining.
+	for i := range chars {
+		c := &chars[i]
+		f := &c.forms[form]
+
+		if !f.isOneWay && len(f.decomp) == 2 {
+			f0 := &chars[f.decomp[0]].forms[form]
+			f1 := &chars[f.decomp[1]].forms[form]
+			if !f0.isOneWay {
+				f0.combinesForward = true
+			}
+			if !f1.isOneWay {
+				f1.combinesBackward = true
+			}
+		}
+		if isHangulWithoutJamoT(rune(i)) {
+			f.combinesForward = true
+		}
+	}
+
+	// Phase 3: quick check values.
+	for i := range chars {
+		c := &chars[i]
+		f := &c.forms[form]
+
+		switch {
+		case len(f.decomp) > 0:
+			f.quickCheck[MDecomposed] = QCNo
+		case isHangul(rune(i)):
+			f.quickCheck[MDecomposed] = QCNo
+		default:
+			f.quickCheck[MDecomposed] = QCYes
+		}
+		switch {
+		case f.isOneWay:
+			f.quickCheck[MComposed] = QCNo
+		case (i & 0xffff00) == JamoLBase:
+			f.quickCheck[MComposed] = QCYes
+			if JamoLBase <= i && i < JamoLEnd {
+				f.combinesForward = true
+			}
+			if JamoVBase <= i && i < JamoVEnd {
+				f.quickCheck[MComposed] = QCMaybe
+				f.combinesBackward = true
+				f.combinesForward = true
+			}
+			if JamoTBase <= i && i < JamoTEnd {
+				f.quickCheck[MComposed] = QCMaybe
+				f.combinesBackward = true
+			}
+		case !f.combinesBackward:
+			f.quickCheck[MComposed] = QCYes
+		default:
+			f.quickCheck[MComposed] = QCMaybe
+		}
+	}
+}
+
+func computeNonStarterCounts() {
+	// Phase 4: leading and trailing non-starter count
+	for i := range chars {
+		c := &chars[i]
+
+		runes := []rune{rune(i)}
+		// We always use FCompatibility so that the CGJ insertion points do not
+		// change for repeated normalizations with different forms.
+		if exp := c.forms[FCompatibility].expandedDecomp; len(exp) > 0 {
+			runes = exp
+		}
+		// We consider runes that combine backwards to be non-starters for the
+		// purpose of Stream-Safe Text Processing.
+		for _, r := range runes {
+			if cr := &chars[r]; cr.ccc == 0 && !cr.forms[FCompatibility].combinesBackward {
+				break
+			}
+			c.nLeadingNonStarters++
+		}
+		for i := len(runes) - 1; i >= 0; i-- {
+			if cr := &chars[runes[i]]; cr.ccc == 0 && !cr.forms[FCompatibility].combinesBackward {
+				break
+			}
+			c.nTrailingNonStarters++
+		}
+		if c.nTrailingNonStarters > 3 {
+			log.Fatalf("%U: Decomposition with more than 3 (%d) trailing modifiers (%U)", i, c.nTrailingNonStarters, runes)
+		}
+
+		if isHangul(rune(i)) {
+			c.nTrailingNonStarters = 2
+			if isHangulWithoutJamoT(rune(i)) {
+				c.nTrailingNonStarters = 1
+			}
+		}
+
+		if l, t := c.nLeadingNonStarters, c.nTrailingNonStarters; l > 0 && l != t {
+			log.Fatalf("%U: number of leading and trailing non-starters should be equal (%d vs %d)", i, l, t)
+		}
+		if t := c.nTrailingNonStarters; t > 3 {
+			log.Fatalf("%U: number of trailing non-starters is %d > 3", t)
+		}
+	}
+}
+
+func printBytes(w io.Writer, b []byte, name string) {
+	fmt.Fprintf(w, "// %s: %d bytes\n", name, len(b))
+	fmt.Fprintf(w, "var %s = [...]byte {", name)
+	for i, c := range b {
+		switch {
+		case i%64 == 0:
+			fmt.Fprintf(w, "\n// Bytes %x - %x\n", i, i+63)
+		case i%8 == 0:
+			fmt.Fprintf(w, "\n")
+		}
+		fmt.Fprintf(w, "0x%.2X, ", c)
+	}
+	fmt.Fprint(w, "\n}\n\n")
+}
+
+// See forminfo.go for format.
+func makeEntry(f *FormInfo, c *Char) uint16 {
+	e := uint16(0)
+	if r := c.codePoint; HangulBase <= r && r < HangulEnd {
+		e |= 0x40
+	}
+	if f.combinesForward {
+		e |= 0x20
+	}
+	if f.quickCheck[MDecomposed] == QCNo {
+		e |= 0x4
+	}
+	switch f.quickCheck[MComposed] {
+	case QCYes:
+	case QCNo:
+		e |= 0x10
+	case QCMaybe:
+		e |= 0x18
+	default:
+		log.Fatalf("Illegal quickcheck value %v.", f.quickCheck[MComposed])
+	}
+	e |= uint16(c.nTrailingNonStarters)
+	return e
+}
+
+// decompSet keeps track of unique decompositions, grouped by whether
+// the decomposition is followed by a trailing and/or leading CCC.
+type decompSet [7]map[string]bool
+
+const (
+	normalDecomp = iota
+	firstMulti
+	firstCCC
+	endMulti
+	firstLeadingCCC
+	firstCCCZeroExcept
+	firstStarterWithNLead
+	lastDecomp
+)
+
+var cname = []string{"firstMulti", "firstCCC", "endMulti", "firstLeadingCCC", "firstCCCZeroExcept", "firstStarterWithNLead", "lastDecomp"}
+
+func makeDecompSet() decompSet {
+	m := decompSet{}
+	for i := range m {
+		m[i] = make(map[string]bool)
+	}
+	return m
+}
+func (m *decompSet) insert(key int, s string) {
+	m[key][s] = true
+}
+
+func printCharInfoTables(w io.Writer) int {
+	mkstr := func(r rune, f *FormInfo) (int, string) {
+		d := f.expandedDecomp
+		s := string([]rune(d))
+		if max := 1 << 6; len(s) >= max {
+			const msg = "%U: too many bytes in decomposition: %d >= %d"
+			log.Fatalf(msg, r, len(s), max)
+		}
+		head := uint8(len(s))
+		if f.quickCheck[MComposed] != QCYes {
+			head |= 0x40
+		}
+		if f.combinesForward {
+			head |= 0x80
+		}
+		s = string([]byte{head}) + s
+
+		lccc := ccc(d[0])
+		tccc := ccc(d[len(d)-1])
+		cc := ccc(r)
+		if cc != 0 && lccc == 0 && tccc == 0 {
+			log.Fatalf("%U: trailing and leading ccc are 0 for non-zero ccc %d", r, cc)
+		}
+		if tccc < lccc && lccc != 0 {
+			const msg = "%U: lccc (%d) must be <= tcc (%d)"
+			log.Fatalf(msg, r, lccc, tccc)
+		}
+		index := normalDecomp
+		nTrail := chars[r].nTrailingNonStarters
+		nLead := chars[r].nLeadingNonStarters
+		if tccc > 0 || lccc > 0 || nTrail > 0 {
+			tccc <<= 2
+			tccc |= nTrail
+			s += string([]byte{tccc})
+			index = endMulti
+			for _, r := range d[1:] {
+				if ccc(r) == 0 {
+					index = firstCCC
+				}
+			}
+			if lccc > 0 || nLead > 0 {
+				s += string([]byte{lccc})
+				if index == firstCCC {
+					log.Fatalf("%U: multi-segment decomposition not supported for decompositions with leading CCC != 0", r)
+				}
+				index = firstLeadingCCC
+			}
+			if cc != lccc {
+				if cc != 0 {
+					log.Fatalf("%U: for lccc != ccc, expected ccc to be 0; was %d", r, cc)
+				}
+				index = firstCCCZeroExcept
+			}
+		} else if len(d) > 1 {
+			index = firstMulti
+		}
+		return index, s
+	}
+
+	decompSet := makeDecompSet()
+	const nLeadStr = "\x00\x01" // 0-byte length and tccc with nTrail.
+	decompSet.insert(firstStarterWithNLead, nLeadStr)
+
+	// Store the uniqued decompositions in a byte buffer,
+	// preceded by their byte length.
+	for _, c := range chars {
+		for _, f := range c.forms {
+			if len(f.expandedDecomp) == 0 {
+				continue
+			}
+			if f.combinesBackward {
+				log.Fatalf("%U: combinesBackward and decompose", c.codePoint)
+			}
+			index, s := mkstr(c.codePoint, &f)
+			decompSet.insert(index, s)
+		}
+	}
+
+	decompositions := bytes.NewBuffer(make([]byte, 0, 10000))
+	size := 0
+	positionMap := make(map[string]uint16)
+	decompositions.WriteString("\000")
+	fmt.Fprintln(w, "const (")
+	for i, m := range decompSet {
+		sa := []string{}
+		for s := range m {
+			sa = append(sa, s)
+		}
+		sort.Strings(sa)
+		for _, s := range sa {
+			p := decompositions.Len()
+			decompositions.WriteString(s)
+			positionMap[s] = uint16(p)
+		}
+		if cname[i] != "" {
+			fmt.Fprintf(w, "%s = 0x%X\n", cname[i], decompositions.Len())
+		}
+	}
+	fmt.Fprintln(w, "maxDecomp = 0x8000")
+	fmt.Fprintln(w, ")")
+	b := decompositions.Bytes()
+	printBytes(w, b, "decomps")
+	size += len(b)
+
+	varnames := []string{"nfc", "nfkc"}
+	for i := 0; i < FNumberOfFormTypes; i++ {
+		trie := triegen.NewTrie(varnames[i])
+
+		for r, c := range chars {
+			f := c.forms[i]
+			d := f.expandedDecomp
+			if len(d) != 0 {
+				_, key := mkstr(c.codePoint, &f)
+				trie.Insert(rune(r), uint64(positionMap[key]))
+				if c.ccc != ccc(d[0]) {
+					// We assume the lead ccc of a decomposition !=0 in this case.
+					if ccc(d[0]) == 0 {
+						log.Fatalf("Expected leading CCC to be non-zero; ccc is %d", c.ccc)
+					}
+				}
+			} else if c.nLeadingNonStarters > 0 && len(f.expandedDecomp) == 0 && c.ccc == 0 && !f.combinesBackward {
+				// Handle cases where it can't be detected that the nLead should be equal
+				// to nTrail.
+				trie.Insert(c.codePoint, uint64(positionMap[nLeadStr]))
+			} else if v := makeEntry(&f, &c)<<8 | uint16(c.ccc); v != 0 {
+				trie.Insert(c.codePoint, uint64(0x8000|v))
+			}
+		}
+		sz, err := trie.Gen(w, triegen.Compact(&normCompacter{name: varnames[i]}))
+		if err != nil {
+			log.Fatal(err)
+		}
+		size += sz
+	}
+	return size
+}
+
+func contains(sa []string, s string) bool {
+	for _, a := range sa {
+		if a == s {
+			return true
+		}
+	}
+	return false
+}
+
+func makeTables() {
+	w := &bytes.Buffer{}
+
+	size := 0
+	if *tablelist == "" {
+		return
+	}
+	list := strings.Split(*tablelist, ",")
+	if *tablelist == "all" {
+		list = []string{"recomp", "info"}
+	}
+
+	// Compute maximum decomposition size.
+	max := 0
+	for _, c := range chars {
+		if n := len(string(c.forms[FCompatibility].expandedDecomp)); n > max {
+			max = n
+		}
+	}
+
+	fmt.Fprintln(w, "const (")
+	fmt.Fprintln(w, "\t// Version is the Unicode edition from which the tables are derived.")
+	fmt.Fprintf(w, "\tVersion = %q\n", gen.UnicodeVersion())
+	fmt.Fprintln(w)
+	fmt.Fprintln(w, "\t// MaxTransformChunkSize indicates the maximum number of bytes that Transform")
+	fmt.Fprintln(w, "\t// may need to write atomically for any Form. Making a destination buffer at")
+	fmt.Fprintln(w, "\t// least this size ensures that Transform can always make progress and that")
+	fmt.Fprintln(w, "\t// the user does not need to grow the buffer on an ErrShortDst.")
+	fmt.Fprintf(w, "\tMaxTransformChunkSize = %d+maxNonStarters*4\n", len(string(0x034F))+max)
+	fmt.Fprintln(w, ")\n")
+
+	// Print the CCC remap table.
+	size += len(cccMap)
+	fmt.Fprintf(w, "var ccc = [%d]uint8{", len(cccMap))
+	for i := 0; i < len(cccMap); i++ {
+		if i%8 == 0 {
+			fmt.Fprintln(w)
+		}
+		fmt.Fprintf(w, "%3d, ", cccMap[uint8(i)])
+	}
+	fmt.Fprintln(w, "\n}\n")
+
+	if contains(list, "info") {
+		size += printCharInfoTables(w)
+	}
+
+	if contains(list, "recomp") {
+		// Note that we use 32 bit keys, instead of 64 bit.
+		// This clips the bits of three entries, but we know
+		// this won't cause a collision. The compiler will catch
+		// any changes made to UnicodeData.txt that introduces
+		// a collision.
+		// Note that the recomposition map for NFC and NFKC
+		// are identical.
+
+		// Recomposition map
+		nrentries := 0
+		for _, c := range chars {
+			f := c.forms[FCanonical]
+			if !f.isOneWay && len(f.decomp) > 0 {
+				nrentries++
+			}
+		}
+		sz := nrentries * 8
+		size += sz
+		fmt.Fprintf(w, "// recompMap: %d bytes (entries only)\n", sz)
+		fmt.Fprintln(w, "var recompMap = map[uint32]rune{")
+		for i, c := range chars {
+			f := c.forms[FCanonical]
+			d := f.decomp
+			if !f.isOneWay && len(d) > 0 {
+				key := uint32(uint16(d[0]))<<16 + uint32(uint16(d[1]))
+				fmt.Fprintf(w, "0x%.8X: 0x%.4X,\n", key, i)
+			}
+		}
+		fmt.Fprintf(w, "}\n\n")
+	}
+
+	fmt.Fprintf(w, "// Total size of tables: %dKB (%d bytes)\n", (size+512)/1024, size)
+	gen.WriteGoFile("tables.go", "norm", w.Bytes())
+}
+
+func printChars() {
+	if *verbose {
+		for _, c := range chars {
+			if !c.isValid() || c.state == SMissing {
+				continue
+			}
+			fmt.Println(c)
+		}
+	}
+}
+
+// verifyComputed does various consistency tests.
+func verifyComputed() {
+	for i, c := range chars {
+		for _, f := range c.forms {
+			isNo := (f.quickCheck[MDecomposed] == QCNo)
+			if (len(f.decomp) > 0) != isNo && !isHangul(rune(i)) {
+				log.Fatalf("%U: NF*D QC must be No if rune decomposes", i)
+			}
+
+			isMaybe := f.quickCheck[MComposed] == QCMaybe
+			if f.combinesBackward != isMaybe {
+				log.Fatalf("%U: NF*C QC must be Maybe if combinesBackward", i)
+			}
+			if len(f.decomp) > 0 && f.combinesForward && isMaybe {
+				log.Fatalf("%U: NF*C QC must be Yes or No if combinesForward and decomposes", i)
+			}
+
+			if len(f.expandedDecomp) != 0 {
+				continue
+			}
+			if a, b := c.nLeadingNonStarters > 0, (c.ccc > 0 || f.combinesBackward); a != b {
+				// We accept these runes to be treated differently (it only affects
+				// segment breaking in iteration, most likely on improper use), but
+				// reconsider if more characters are added.
+				// U+FF9E HALFWIDTH KATAKANA VOICED SOUND MARK;Lm;0;L;<narrow> 3099;;;;N;;;;;
+				// U+FF9F HALFWIDTH KATAKANA SEMI-VOICED SOUND MARK;Lm;0;L;<narrow> 309A;;;;N;;;;;
+				// U+3133 HANGUL LETTER KIYEOK-SIOS;Lo;0;L;<compat> 11AA;;;;N;HANGUL LETTER GIYEOG SIOS;;;;
+				// U+318E HANGUL LETTER ARAEAE;Lo;0;L;<compat> 11A1;;;;N;HANGUL LETTER ALAE AE;;;;
+				// U+FFA3 HALFWIDTH HANGUL LETTER KIYEOK-SIOS;Lo;0;L;<narrow> 3133;;;;N;HALFWIDTH HANGUL LETTER GIYEOG SIOS;;;;
+				// U+FFDC HALFWIDTH HANGUL LETTER I;Lo;0;L;<narrow> 3163;;;;N;;;;;
+				if i != 0xFF9E && i != 0xFF9F && !(0x3133 <= i && i <= 0x318E) && !(0xFFA3 <= i && i <= 0xFFDC) {
+					log.Fatalf("%U: nLead was %v; want %v", i, a, b)
+				}
+			}
+		}
+		nfc := c.forms[FCanonical]
+		nfkc := c.forms[FCompatibility]
+		if nfc.combinesBackward != nfkc.combinesBackward {
+			log.Fatalf("%U: Cannot combine combinesBackward\n", c.codePoint)
+		}
+	}
+}
+
+// Use values in DerivedNormalizationProps.txt to compare against the
+// values we computed.
+// DerivedNormalizationProps.txt has form:
+// 00C0..00C5    ; NFD_QC; N # ...
+// 0374          ; NFD_QC; N # ...
+// See http://unicode.org/reports/tr44/ for full explanation
+func testDerived() {
+	f := gen.OpenUCDFile("DerivedNormalizationProps.txt")
+	defer f.Close()
+	p := ucd.New(f)
+	for p.Next() {
+		r := p.Rune(0)
+		c := &chars[r]
+
+		var ftype, mode int
+		qt := p.String(1)
+		switch qt {
+		case "NFC_QC":
+			ftype, mode = FCanonical, MComposed
+		case "NFD_QC":
+			ftype, mode = FCanonical, MDecomposed
+		case "NFKC_QC":
+			ftype, mode = FCompatibility, MComposed
+		case "NFKD_QC":
+			ftype, mode = FCompatibility, MDecomposed
+		default:
+			continue
+		}
+		var qr QCResult
+		switch p.String(2) {
+		case "Y":
+			qr = QCYes
+		case "N":
+			qr = QCNo
+		case "M":
+			qr = QCMaybe
+		default:
+			log.Fatalf(`Unexpected quick check value "%s"`, p.String(2))
+		}
+		if got := c.forms[ftype].quickCheck[mode]; got != qr {
+			log.Printf("%U: FAILED %s (was %v need %v)\n", r, qt, got, qr)
+		}
+		c.forms[ftype].verified[mode] = true
+	}
+	if err := p.Err(); err != nil {
+		log.Fatal(err)
+	}
+	// Any unspecified value must be QCYes. Verify this.
+	for i, c := range chars {
+		for j, fd := range c.forms {
+			for k, qr := range fd.quickCheck {
+				if !fd.verified[k] && qr != QCYes {
+					m := "%U: FAIL F:%d M:%d (was %v need Yes) %s\n"
+					log.Printf(m, i, j, k, qr, c.name)
+				}
+			}
+		}
+	}
+}
+
+var testHeader = `const (
+	Yes = iota
+	No
+	Maybe
+)
+
+type formData struct {
+	qc              uint8
+	combinesForward bool
+	decomposition   string
+}
+
+type runeData struct {
+	r      rune
+	ccc    uint8
+	nLead  uint8
+	nTrail uint8
+	f      [2]formData // 0: canonical; 1: compatibility
+}
+
+func f(qc uint8, cf bool, dec string) [2]formData {
+	return [2]formData{{qc, cf, dec}, {qc, cf, dec}}
+}
+
+func g(qc, qck uint8, cf, cfk bool, d, dk string) [2]formData {
+	return [2]formData{{qc, cf, d}, {qck, cfk, dk}}
+}
+
+var testData = []runeData{
+`
+
+func printTestdata() {
+	type lastInfo struct {
+		ccc    uint8
+		nLead  uint8
+		nTrail uint8
+		f      string
+	}
+
+	last := lastInfo{}
+	w := &bytes.Buffer{}
+	fmt.Fprintf(w, testHeader)
+	for r, c := range chars {
+		f := c.forms[FCanonical]
+		qc, cf, d := f.quickCheck[MComposed], f.combinesForward, string(f.expandedDecomp)
+		f = c.forms[FCompatibility]
+		qck, cfk, dk := f.quickCheck[MComposed], f.combinesForward, string(f.expandedDecomp)
+		s := ""
+		if d == dk && qc == qck && cf == cfk {
+			s = fmt.Sprintf("f(%s, %v, %q)", qc, cf, d)
+		} else {
+			s = fmt.Sprintf("g(%s, %s, %v, %v, %q, %q)", qc, qck, cf, cfk, d, dk)
+		}
+		current := lastInfo{c.ccc, c.nLeadingNonStarters, c.nTrailingNonStarters, s}
+		if last != current {
+			fmt.Fprintf(w, "\t{0x%x, %d, %d, %d, %s},\n", r, c.origCCC, c.nLeadingNonStarters, c.nTrailingNonStarters, s)
+			last = current
+		}
+	}
+	fmt.Fprintln(w, "}")
+	gen.WriteGoFile("data_test.go", "norm", w.Bytes())
+}

vendor/golang.org/x/text/unicode/norm/normalize.go

@@ -0,0 +1,609 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Note: the file data_test.go that is generated should not be checked in.
+//go:generate go run maketables.go triegen.go
+//go:generate go test -tags test
+
+// Package norm contains types and functions for normalizing Unicode strings.
+package norm // import "golang.org/x/text/unicode/norm"
+
+import (
+	"unicode/utf8"
+
+	"golang.org/x/text/transform"
+)
+
+// A Form denotes a canonical representation of Unicode code points.
+// The Unicode-defined normalization and equivalence forms are:
+//
+//   NFC   Unicode Normalization Form C
+//   NFD   Unicode Normalization Form D
+//   NFKC  Unicode Normalization Form KC
+//   NFKD  Unicode Normalization Form KD
+//
+// For a Form f, this documentation uses the notation f(x) to mean
+// the bytes or string x converted to the given form.
+// A position n in x is called a boundary if conversion to the form can
+// proceed independently on both sides:
+//   f(x) == append(f(x[0:n]), f(x[n:])...)
+//
+// References: http://unicode.org/reports/tr15/ and
+// http://unicode.org/notes/tn5/.
+type Form int
+
+const (
+	NFC Form = iota
+	NFD
+	NFKC
+	NFKD
+)
+
+// Bytes returns f(b). May return b if f(b) = b.
+func (f Form) Bytes(b []byte) []byte {
+	src := inputBytes(b)
+	ft := formTable[f]
+	n, ok := ft.quickSpan(src, 0, len(b), true)
+	if ok {
+		return b
+	}
+	out := make([]byte, n, len(b))
+	copy(out, b[0:n])
+	rb := reorderBuffer{f: *ft, src: src, nsrc: len(b), out: out, flushF: appendFlush}
+	return doAppendInner(&rb, n)
+}
+
+// String returns f(s).
+func (f Form) String(s string) string {
+	src := inputString(s)
+	ft := formTable[f]
+	n, ok := ft.quickSpan(src, 0, len(s), true)
+	if ok {
+		return s
+	}
+	out := make([]byte, n, len(s))
+	copy(out, s[0:n])
+	rb := reorderBuffer{f: *ft, src: src, nsrc: len(s), out: out, flushF: appendFlush}
+	return string(doAppendInner(&rb, n))
+}
+
+// IsNormal returns true if b == f(b).
+func (f Form) IsNormal(b []byte) bool {
+	src := inputBytes(b)
+	ft := formTable[f]
+	bp, ok := ft.quickSpan(src, 0, len(b), true)
+	if ok {
+		return true
+	}
+	rb := reorderBuffer{f: *ft, src: src, nsrc: len(b)}
+	rb.setFlusher(nil, cmpNormalBytes)
+	for bp < len(b) {
+		rb.out = b[bp:]
+		if bp = decomposeSegment(&rb, bp, true); bp < 0 {
+			return false
+		}
+		bp, _ = rb.f.quickSpan(rb.src, bp, len(b), true)
+	}
+	return true
+}
+
+func cmpNormalBytes(rb *reorderBuffer) bool {
+	b := rb.out
+	for i := 0; i < rb.nrune; i++ {
+		info := rb.rune[i]
+		if int(info.size) > len(b) {
+			return false
+		}
+		p := info.pos
+		pe := p + info.size
+		for ; p < pe; p++ {
+			if b[0] != rb.byte[p] {
+				return false
+			}
+			b = b[1:]
+		}
+	}
+	return true
+}
+
+// IsNormalString returns true if s == f(s).
+func (f Form) IsNormalString(s string) bool {
+	src := inputString(s)
+	ft := formTable[f]
+	bp, ok := ft.quickSpan(src, 0, len(s), true)
+	if ok {
+		return true
+	}
+	rb := reorderBuffer{f: *ft, src: src, nsrc: len(s)}
+	rb.setFlusher(nil, func(rb *reorderBuffer) bool {
+		for i := 0; i < rb.nrune; i++ {
+			info := rb.rune[i]
+			if bp+int(info.size) > len(s) {
+				return false
+			}
+			p := info.pos
+			pe := p + info.size
+			for ; p < pe; p++ {
+				if s[bp] != rb.byte[p] {
+					return false
+				}
+				bp++
+			}
+		}
+		return true
+	})
+	for bp < len(s) {
+		if bp = decomposeSegment(&rb, bp, true); bp < 0 {
+			return false
+		}
+		bp, _ = rb.f.quickSpan(rb.src, bp, len(s), true)
+	}
+	return true
+}
+
+// patchTail fixes a case where a rune may be incorrectly normalized
+// if it is followed by illegal continuation bytes. It returns the
+// patched buffer and whether the decomposition is still in progress.
+func patchTail(rb *reorderBuffer) bool {
+	info, p := lastRuneStart(&rb.f, rb.out)
+	if p == -1 || info.size == 0 {
+		return true
+	}
+	end := p + int(info.size)
+	extra := len(rb.out) - end
+	if extra > 0 {
+		// Potentially allocating memory. However, this only
+		// happens with ill-formed UTF-8.
+		x := make([]byte, 0)
+		x = append(x, rb.out[len(rb.out)-extra:]...)
+		rb.out = rb.out[:end]
+		decomposeToLastBoundary(rb)
+		rb.doFlush()
+		rb.out = append(rb.out, x...)
+		return false
+	}
+	buf := rb.out[p:]
+	rb.out = rb.out[:p]
+	decomposeToLastBoundary(rb)
+	if s := rb.ss.next(info); s == ssStarter {
+		rb.doFlush()
+		rb.ss.first(info)
+	} else if s == ssOverflow {
+		rb.doFlush()
+		rb.insertCGJ()
+		rb.ss = 0
+	}
+	rb.insertUnsafe(inputBytes(buf), 0, info)
+	return true
+}
+
+func appendQuick(rb *reorderBuffer, i int) int {
+	if rb.nsrc == i {
+		return i
+	}
+	end, _ := rb.f.quickSpan(rb.src, i, rb.nsrc, true)
+	rb.out = rb.src.appendSlice(rb.out, i, end)
+	return end
+}
+
+// Append returns f(append(out, b...)).
+// The buffer out must be nil, empty, or equal to f(out).
+func (f Form) Append(out []byte, src ...byte) []byte {
+	return f.doAppend(out, inputBytes(src), len(src))
+}
+
+func (f Form) doAppend(out []byte, src input, n int) []byte {
+	if n == 0 {
+		return out
+	}
+	ft := formTable[f]
+	// Attempt to do a quickSpan first so we can avoid initializing the reorderBuffer.
+	if len(out) == 0 {
+		p, _ := ft.quickSpan(src, 0, n, true)
+		out = src.appendSlice(out, 0, p)
+		if p == n {
+			return out
+		}
+		rb := reorderBuffer{f: *ft, src: src, nsrc: n, out: out, flushF: appendFlush}
+		return doAppendInner(&rb, p)
+	}
+	rb := reorderBuffer{f: *ft, src: src, nsrc: n}
+	return doAppend(&rb, out, 0)
+}
+
+func doAppend(rb *reorderBuffer, out []byte, p int) []byte {
+	rb.setFlusher(out, appendFlush)
+	src, n := rb.src, rb.nsrc
+	doMerge := len(out) > 0
+	if q := src.skipContinuationBytes(p); q > p {
+		// Move leading non-starters to destination.
+		rb.out = src.appendSlice(rb.out, p, q)
+		p = q
+		doMerge = patchTail(rb)
+	}
+	fd := &rb.f
+	if doMerge {
+		var info Properties
+		if p < n {
+			info = fd.info(src, p)
+			if !info.BoundaryBefore() || info.nLeadingNonStarters() > 0 {
+				if p == 0 {
+					decomposeToLastBoundary(rb)
+				}
+				p = decomposeSegment(rb, p, true)
+			}
+		}
+		if info.size == 0 {
+			rb.doFlush()
+			// Append incomplete UTF-8 encoding.
+			return src.appendSlice(rb.out, p, n)
+		}
+		if rb.nrune > 0 {
+			return doAppendInner(rb, p)
+		}
+	}
+	p = appendQuick(rb, p)
+	return doAppendInner(rb, p)
+}
+
+func doAppendInner(rb *reorderBuffer, p int) []byte {
+	for n := rb.nsrc; p < n; {
+		p = decomposeSegment(rb, p, true)
+		p = appendQuick(rb, p)
+	}
+	return rb.out
+}
+
+// AppendString returns f(append(out, []byte(s))).
+// The buffer out must be nil, empty, or equal to f(out).
+func (f Form) AppendString(out []byte, src string) []byte {
+	return f.doAppend(out, inputString(src), len(src))
+}
+
+// QuickSpan returns a boundary n such that b[0:n] == f(b[0:n]).
+// It is not guaranteed to return the largest such n.
+func (f Form) QuickSpan(b []byte) int {
+	n, _ := formTable[f].quickSpan(inputBytes(b), 0, len(b), true)
+	return n
+}
+
+// Span implements transform.SpanningTransformer. It returns a boundary n such
+// that b[0:n] == f(b[0:n]). It is not guaranteed to return the largest such n.
+func (f Form) Span(b []byte, atEOF bool) (n int, err error) {
+	n, ok := formTable[f].quickSpan(inputBytes(b), 0, len(b), atEOF)
+	if n < len(b) {
+		if !ok {
+			err = transform.ErrEndOfSpan
+		} else {
+			err = transform.ErrShortSrc
+		}
+	}
+	return n, err
+}
+
+// SpanString returns a boundary n such that s[0:n] == f(s[0:n]).
+// It is not guaranteed to return the largest such n.
+func (f Form) SpanString(s string, atEOF bool) (n int, err error) {
+	n, ok := formTable[f].quickSpan(inputString(s), 0, len(s), atEOF)
+	if n < len(s) {
+		if !ok {
+			err = transform.ErrEndOfSpan
+		} else {
+			err = transform.ErrShortSrc
+		}
+	}
+	return n, err
+}
+
+// quickSpan returns a boundary n such that src[0:n] == f(src[0:n]) and
+// whether any non-normalized parts were found. If atEOF is false, n will
+// not point past the last segment if this segment might be become
+// non-normalized by appending other runes.
+func (f *formInfo) quickSpan(src input, i, end int, atEOF bool) (n int, ok bool) {
+	var lastCC uint8
+	ss := streamSafe(0)
+	lastSegStart := i
+	for n = end; i < n; {
+		if j := src.skipASCII(i, n); i != j {
+			i = j
+			lastSegStart = i - 1
+			lastCC = 0
+			ss = 0
+			continue
+		}
+		info := f.info(src, i)
+		if info.size == 0 {
+			if atEOF {
+				// include incomplete runes
+				return n, true
+			}
+			return lastSegStart, true
+		}
+		// This block needs to be before the next, because it is possible to
+		// have an overflow for runes that are starters (e.g. with U+FF9E).
+		switch ss.next(info) {
+		case ssStarter:
+			ss.first(info)
+			lastSegStart = i
+		case ssOverflow:
+			return lastSegStart, false
+		case ssSuccess:
+			if lastCC > info.ccc {
+				return lastSegStart, false
+			}
+		}
+		if f.composing {
+			if !info.isYesC() {
+				break
+			}
+		} else {
+			if !info.isYesD() {
+				break
+			}
+		}
+		lastCC = info.ccc
+		i += int(info.size)
+	}
+	if i == n {
+		if !atEOF {
+			n = lastSegStart
+		}
+		return n, true
+	}
+	return lastSegStart, false
+}
+
+// QuickSpanString returns a boundary n such that s[0:n] == f(s[0:n]).
+// It is not guaranteed to return the largest such n.
+func (f Form) QuickSpanString(s string) int {
+	n, _ := formTable[f].quickSpan(inputString(s), 0, len(s), true)
+	return n
+}
+
+// FirstBoundary returns the position i of the first boundary in b
+// or -1 if b contains no boundary.
+func (f Form) FirstBoundary(b []byte) int {
+	return f.firstBoundary(inputBytes(b), len(b))
+}
+
+func (f Form) firstBoundary(src input, nsrc int) int {
+	i := src.skipContinuationBytes(0)
+	if i >= nsrc {
+		return -1
+	}
+	fd := formTable[f]
+	ss := streamSafe(0)
+	// We should call ss.first here, but we can't as the first rune is
+	// skipped already. This means FirstBoundary can't really determine
+	// CGJ insertion points correctly. Luckily it doesn't have to.
+	for {
+		info := fd.info(src, i)
+		if info.size == 0 {
+			return -1
+		}
+		if s := ss.next(info); s != ssSuccess {
+			return i
+		}
+		i += int(info.size)
+		if i >= nsrc {
+			if !info.BoundaryAfter() && !ss.isMax() {
+				return -1
+			}
+			return nsrc
+		}
+	}
+}
+
+// FirstBoundaryInString returns the position i of the first boundary in s
+// or -1 if s contains no boundary.
+func (f Form) FirstBoundaryInString(s string) int {
+	return f.firstBoundary(inputString(s), len(s))
+}
+
+// NextBoundary reports the index of the boundary between the first and next
+// segment in b or -1 if atEOF is false and there are not enough bytes to
+// determine this boundary.
+func (f Form) NextBoundary(b []byte, atEOF bool) int {
+	return f.nextBoundary(inputBytes(b), len(b), atEOF)
+}
+
+// NextBoundaryInString reports the index of the boundary between the first and
+// next segment in b or -1 if atEOF is false and there are not enough bytes to
+// determine this boundary.
+func (f Form) NextBoundaryInString(s string, atEOF bool) int {
+	return f.nextBoundary(inputString(s), len(s), atEOF)
+}
+
+func (f Form) nextBoundary(src input, nsrc int, atEOF bool) int {
+	if nsrc == 0 {
+		if atEOF {
+			return 0
+		}
+		return -1
+	}
+	fd := formTable[f]
+	info := fd.info(src, 0)
+	if info.size == 0 {
+		if atEOF {
+			return 1
+		}
+		return -1
+	}
+	ss := streamSafe(0)
+	ss.first(info)
+
+	for i := int(info.size); i < nsrc; i += int(info.size) {
+		info = fd.info(src, i)
+		if info.size == 0 {
+			if atEOF {
+				return i
+			}
+			return -1
+		}
+		if s := ss.next(info); s != ssSuccess {
+			return i
+		}
+	}
+	if !atEOF && !info.BoundaryAfter() && !ss.isMax() {
+		return -1
+	}
+	return nsrc
+}
+
+// LastBoundary returns the position i of the last boundary in b
+// or -1 if b contains no boundary.
+func (f Form) LastBoundary(b []byte) int {
+	return lastBoundary(formTable[f], b)
+}
+
+func lastBoundary(fd *formInfo, b []byte) int {
+	i := len(b)
+	info, p := lastRuneStart(fd, b)
+	if p == -1 {
+		return -1
+	}
+	if info.size == 0 { // ends with incomplete rune
+		if p == 0 { // starts with incomplete rune
+			return -1
+		}
+		i = p
+		info, p = lastRuneStart(fd, b[:i])
+		if p == -1 { // incomplete UTF-8 encoding or non-starter bytes without a starter
+			return i
+		}
+	}
+	if p+int(info.size) != i { // trailing non-starter bytes: illegal UTF-8
+		return i
+	}
+	if info.BoundaryAfter() {
+		return i
+	}
+	ss := streamSafe(0)
+	v := ss.backwards(info)
+	for i = p; i >= 0 && v != ssStarter; i = p {
+		info, p = lastRuneStart(fd, b[:i])
+		if v = ss.backwards(info); v == ssOverflow {
+			break
+		}
+		if p+int(info.size) != i {
+			if p == -1 { // no boundary found
+				return -1
+			}
+			return i // boundary after an illegal UTF-8 encoding
+		}
+	}
+	return i
+}
+
+// decomposeSegment scans the first segment in src into rb. It inserts 0x034f
+// (Grapheme Joiner) when it encounters a sequence of more than 30 non-starters
+// and returns the number of bytes consumed from src or iShortDst or iShortSrc.
+func decomposeSegment(rb *reorderBuffer, sp int, atEOF bool) int {
+	// Force one character to be consumed.
+	info := rb.f.info(rb.src, sp)
+	if info.size == 0 {
+		return 0
+	}
+	if rb.nrune > 0 {
+		if s := rb.ss.next(info); s == ssStarter {
+			goto end
+		} else if s == ssOverflow {
+			rb.insertCGJ()
+			goto end
+		}
+	} else {
+		rb.ss.first(info)
+	}
+	if err := rb.insertFlush(rb.src, sp, info); err != iSuccess {
+		return int(err)
+	}
+	for {
+		sp += int(info.size)
+		if sp >= rb.nsrc {
+			if !atEOF && !info.BoundaryAfter() {
+				return int(iShortSrc)
+			}
+			break
+		}
+		info = rb.f.info(rb.src, sp)
+		if info.size == 0 {
+			if !atEOF {
+				return int(iShortSrc)
+			}
+			break
+		}
+		if s := rb.ss.next(info); s == ssStarter {
+			break
+		} else if s == ssOverflow {
+			rb.insertCGJ()
+			break
+		}
+		if err := rb.insertFlush(rb.src, sp, info); err != iSuccess {
+			return int(err)
+		}
+	}
+end:
+	if !rb.doFlush() {
+		return int(iShortDst)
+	}
+	return sp
+}
+
+// lastRuneStart returns the runeInfo and position of the last
+// rune in buf or the zero runeInfo and -1 if no rune was found.
+func lastRuneStart(fd *formInfo, buf []byte) (Properties, int) {
+	p := len(buf) - 1
+	for ; p >= 0 && !utf8.RuneStart(buf[p]); p-- {
+	}
+	if p < 0 {
+		return Properties{}, -1
+	}
+	return fd.info(inputBytes(buf), p), p
+}
+
+// decomposeToLastBoundary finds an open segment at the end of the buffer
+// and scans it into rb. Returns the buffer minus the last segment.
+func decomposeToLastBoundary(rb *reorderBuffer) {
+	fd := &rb.f
+	info, i := lastRuneStart(fd, rb.out)
+	if int(info.size) != len(rb.out)-i {
+		// illegal trailing continuation bytes
+		return
+	}
+	if info.BoundaryAfter() {
+		return
+	}
+	var add [maxNonStarters + 1]Properties // stores runeInfo in reverse order
+	padd := 0
+	ss := streamSafe(0)
+	p := len(rb.out)
+	for {
+		add[padd] = info
+		v := ss.backwards(info)
+		if v == ssOverflow {
+			// Note that if we have an overflow, it the string we are appending to
+			// is not correctly normalized. In this case the behavior is undefined.
+			break
+		}
+		padd++
+		p -= int(info.size)
+		if v == ssStarter || p < 0 {
+			break
+		}
+		info, i = lastRuneStart(fd, rb.out[:p])
+		if int(info.size) != p-i {
+			break
+		}
+	}
+	rb.ss = ss
+	// Copy bytes for insertion as we may need to overwrite rb.out.
+	var buf [maxBufferSize * utf8.UTFMax]byte
+	cp := buf[:copy(buf[:], rb.out[p:])]
+	rb.out = rb.out[:p]
+	for padd--; padd >= 0; padd-- {
+		info = add[padd]
+		rb.insertUnsafe(inputBytes(cp), 0, info)
+		cp = cp[info.size:]
+	}
+}

vendor/golang.org/x/text/unicode/norm/readwriter.go

@@ -0,0 +1,125 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package norm
+
+import "io"
+
+type normWriter struct {
+	rb  reorderBuffer
+	w   io.Writer
+	buf []byte
+}
+
+// Write implements the standard write interface.  If the last characters are
+// not at a normalization boundary, the bytes will be buffered for the next
+// write. The remaining bytes will be written on close.
+func (w *normWriter) Write(data []byte) (n int, err error) {
+	// Process data in pieces to keep w.buf size bounded.
+	const chunk = 4000
+
+	for len(data) > 0 {
+		// Normalize into w.buf.
+		m := len(data)
+		if m > chunk {
+			m = chunk
+		}
+		w.rb.src = inputBytes(data[:m])
+		w.rb.nsrc = m
+		w.buf = doAppend(&w.rb, w.buf, 0)
+		data = data[m:]
+		n += m
+
+		// Write out complete prefix, save remainder.
+		// Note that lastBoundary looks back at most 31 runes.
+		i := lastBoundary(&w.rb.f, w.buf)
+		if i == -1 {
+			i = 0
+		}
+		if i > 0 {
+			if _, err = w.w.Write(w.buf[:i]); err != nil {
+				break
+			}
+			bn := copy(w.buf, w.buf[i:])
+			w.buf = w.buf[:bn]
+		}
+	}
+	return n, err
+}
+
+// Close forces data that remains in the buffer to be written.
+func (w *normWriter) Close() error {
+	if len(w.buf) > 0 {
+		_, err := w.w.Write(w.buf)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// Writer returns a new writer that implements Write(b)
+// by writing f(b) to w.  The returned writer may use an
+// an internal buffer to maintain state across Write calls.
+// Calling its Close method writes any buffered data to w.
+func (f Form) Writer(w io.Writer) io.WriteCloser {
+	wr := &normWriter{rb: reorderBuffer{}, w: w}
+	wr.rb.init(f, nil)
+	return wr
+}
+
+type normReader struct {
+	rb           reorderBuffer
+	r            io.Reader
+	inbuf        []byte
+	outbuf       []byte
+	bufStart     int
+	lastBoundary int
+	err          error
+}
+
+// Read implements the standard read interface.
+func (r *normReader) Read(p []byte) (int, error) {
+	for {
+		if r.lastBoundary-r.bufStart > 0 {
+			n := copy(p, r.outbuf[r.bufStart:r.lastBoundary])
+			r.bufStart += n
+			if r.lastBoundary-r.bufStart > 0 {
+				return n, nil
+			}
+			return n, r.err
+		}
+		if r.err != nil {
+			return 0, r.err
+		}
+		outn := copy(r.outbuf, r.outbuf[r.lastBoundary:])
+		r.outbuf = r.outbuf[0:outn]
+		r.bufStart = 0
+
+		n, err := r.r.Read(r.inbuf)
+		r.rb.src = inputBytes(r.inbuf[0:n])
+		r.rb.nsrc, r.err = n, err
+		if n > 0 {
+			r.outbuf = doAppend(&r.rb, r.outbuf, 0)
+		}
+		if err == io.EOF {
+			r.lastBoundary = len(r.outbuf)
+		} else {
+			r.lastBoundary = lastBoundary(&r.rb.f, r.outbuf)
+			if r.lastBoundary == -1 {
+				r.lastBoundary = 0
+			}
+		}
+	}
+}
+
+// Reader returns a new reader that implements Read
+// by reading data from r and returning f(data).
+func (f Form) Reader(r io.Reader) io.Reader {
+	const chunk = 4000
+	buf := make([]byte, chunk)
+	rr := &normReader{rb: reorderBuffer{}, r: r, inbuf: buf}
+	rr.rb.init(f, buf)
+	return rr
+}

vendor/golang.org/x/text/unicode/norm/transform.go

@@ -0,0 +1,88 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package norm
+
+import (
+	"unicode/utf8"
+
+	"golang.org/x/text/transform"
+)
+
+// Reset implements the Reset method of the transform.Transformer interface.
+func (Form) Reset() {}
+
+// Transform implements the Transform method of the transform.Transformer
+// interface. It may need to write segments of up to MaxSegmentSize at once.
+// Users should either catch ErrShortDst and allow dst to grow or have dst be at
+// least of size MaxTransformChunkSize to be guaranteed of progress.
+func (f Form) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
+	n := 0
+	// Cap the maximum number of src bytes to check.
+	b := src
+	eof := atEOF
+	if ns := len(dst); ns < len(b) {
+		err = transform.ErrShortDst
+		eof = false
+		b = b[:ns]
+	}
+	i, ok := formTable[f].quickSpan(inputBytes(b), n, len(b), eof)
+	n += copy(dst[n:], b[n:i])
+	if !ok {
+		nDst, nSrc, err = f.transform(dst[n:], src[n:], atEOF)
+		return nDst + n, nSrc + n, err
+	}
+	if n < len(src) && !atEOF {
+		err = transform.ErrShortSrc
+	}
+	return n, n, err
+}
+
+func flushTransform(rb *reorderBuffer) bool {
+	// Write out (must fully fit in dst, or else it is a ErrShortDst).
+	if len(rb.out) < rb.nrune*utf8.UTFMax {
+		return false
+	}
+	rb.out = rb.out[rb.flushCopy(rb.out):]
+	return true
+}
+
+var errs = []error{nil, transform.ErrShortDst, transform.ErrShortSrc}
+
+// transform implements the transform.Transformer interface. It is only called
+// when quickSpan does not pass for a given string.
+func (f Form) transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
+	// TODO: get rid of reorderBuffer. See CL 23460044.
+	rb := reorderBuffer{}
+	rb.init(f, src)
+	for {
+		// Load segment into reorder buffer.
+		rb.setFlusher(dst[nDst:], flushTransform)
+		end := decomposeSegment(&rb, nSrc, atEOF)
+		if end < 0 {
+			return nDst, nSrc, errs[-end]
+		}
+		nDst = len(dst) - len(rb.out)
+		nSrc = end
+
+		// Next quickSpan.
+		end = rb.nsrc
+		eof := atEOF
+		if n := nSrc + len(dst) - nDst; n < end {
+			err = transform.ErrShortDst
+			end = n
+			eof = false
+		}
+		end, ok := rb.f.quickSpan(rb.src, nSrc, end, eof)
+		n := copy(dst[nDst:], rb.src.bytes[nSrc:end])
+		nSrc += n
+		nDst += n
+		if ok {
+			if n < rb.nsrc && !atEOF {
+				err = transform.ErrShortSrc
+			}
+			return nDst, nSrc, err
+		}
+	}
+}

vendor/golang.org/x/text/unicode/norm/trie.go

@@ -0,0 +1,54 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package norm
+
+type valueRange struct {
+	value  uint16 // header: value:stride
+	lo, hi byte   // header: lo:n
+}
+
+type sparseBlocks struct {
+	values []valueRange
+	offset []uint16
+}
+
+var nfcSparse = sparseBlocks{
+	values: nfcSparseValues[:],
+	offset: nfcSparseOffset[:],
+}
+
+var nfkcSparse = sparseBlocks{
+	values: nfkcSparseValues[:],
+	offset: nfkcSparseOffset[:],
+}
+
+var (
+	nfcData  = newNfcTrie(0)
+	nfkcData = newNfkcTrie(0)
+)
+
+// lookupValue determines the type of block n and looks up the value for b.
+// For n < t.cutoff, the block is a simple lookup table. Otherwise, the block
+// is a list of ranges with an accompanying value. Given a matching range r,
+// the value for b is by r.value + (b - r.lo) * stride.
+func (t *sparseBlocks) lookup(n uint32, b byte) uint16 {
+	offset := t.offset[n]
+	header := t.values[offset]
+	lo := offset + 1
+	hi := lo + uint16(header.lo)
+	for lo < hi {
+		m := lo + (hi-lo)/2
+		r := t.values[m]
+		if r.lo <= b && b <= r.hi {
+			return r.value + uint16(b-r.lo)*header.value
+		}
+		if b < r.lo {
+			hi = m
+		} else {
+			lo = m + 1
+		}
+	}
+	return 0
+}

vendor/golang.org/x/text/unicode/norm/triegen.go

@@ -0,0 +1,117 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+
+// Trie table generator.
+// Used by make*tables tools to generate a go file with trie data structures
+// for mapping UTF-8 to a 16-bit value. All but the last byte in a UTF-8 byte
+// sequence are used to lookup offsets in the index table to be used for the
+// next byte. The last byte is used to index into a table with 16-bit values.
+
+package main
+
+import (
+	"fmt"
+	"io"
+)
+
+const maxSparseEntries = 16
+
+type normCompacter struct {
+	sparseBlocks [][]uint64
+	sparseOffset []uint16
+	sparseCount  int
+	name         string
+}
+
+func mostFrequentStride(a []uint64) int {
+	counts := make(map[int]int)
+	var v int
+	for _, x := range a {
+		if stride := int(x) - v; v != 0 && stride >= 0 {
+			counts[stride]++
+		}
+		v = int(x)
+	}
+	var maxs, maxc int
+	for stride, cnt := range counts {
+		if cnt > maxc || (cnt == maxc && stride < maxs) {
+			maxs, maxc = stride, cnt
+		}
+	}
+	return maxs
+}
+
+func countSparseEntries(a []uint64) int {
+	stride := mostFrequentStride(a)
+	var v, count int
+	for _, tv := range a {
+		if int(tv)-v != stride {
+			if tv != 0 {
+				count++
+			}
+		}
+		v = int(tv)
+	}
+	return count
+}
+
+func (c *normCompacter) Size(v []uint64) (sz int, ok bool) {
+	if n := countSparseEntries(v); n <= maxSparseEntries {
+		return (n+1)*4 + 2, true
+	}
+	return 0, false
+}
+
+func (c *normCompacter) Store(v []uint64) uint32 {
+	h := uint32(len(c.sparseOffset))
+	c.sparseBlocks = append(c.sparseBlocks, v)
+	c.sparseOffset = append(c.sparseOffset, uint16(c.sparseCount))
+	c.sparseCount += countSparseEntries(v) + 1
+	return h
+}
+
+func (c *normCompacter) Handler() string {
+	return c.name + "Sparse.lookup"
+}
+
+func (c *normCompacter) Print(w io.Writer) (retErr error) {
+	p := func(f string, x ...interface{}) {
+		if _, err := fmt.Fprintf(w, f, x...); retErr == nil && err != nil {
+			retErr = err
+		}
+	}
+
+	ls := len(c.sparseBlocks)
+	p("// %sSparseOffset: %d entries, %d bytes\n", c.name, ls, ls*2)
+	p("var %sSparseOffset = %#v\n\n", c.name, c.sparseOffset)
+
+	ns := c.sparseCount
+	p("// %sSparseValues: %d entries, %d bytes\n", c.name, ns, ns*4)
+	p("var %sSparseValues = [%d]valueRange {", c.name, ns)
+	for i, b := range c.sparseBlocks {
+		p("\n// Block %#x, offset %#x", i, c.sparseOffset[i])
+		var v int
+		stride := mostFrequentStride(b)
+		n := countSparseEntries(b)
+		p("\n{value:%#04x,lo:%#02x},", stride, uint8(n))
+		for i, nv := range b {
+			if int(nv)-v != stride {
+				if v != 0 {
+					p(",hi:%#02x},", 0x80+i-1)
+				}
+				if nv != 0 {
+					p("\n{value:%#04x,lo:%#02x", nv, 0x80+i)
+				}
+			}
+			v = int(nv)
+		}
+		if v != 0 {
+			p(",hi:%#02x},", 0x80+len(b)-1)
+		}
+	}
+	p("\n}\n\n")
+	return
+}

vendor/google.golang.org/genproto/LICENSE

@@ -0,0 +1,202 @@
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
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+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/google.golang.org/genproto/googleapis/rpc/status/status.pb.go

@@ -0,0 +1,144 @@
+// Code generated by protoc-gen-go.
+// source: google/rpc/status.proto
+// DO NOT EDIT!
+
+/*
+Package status is a generated protocol buffer package.
+
+It is generated from these files:
+	google/rpc/status.proto
+
+It has these top-level messages:
+	Status
+*/
+package status
+
+import proto "github.com/golang/protobuf/proto"
+import fmt "fmt"
+import math "math"
+import google_protobuf "github.com/golang/protobuf/ptypes/any"
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
+
+// The `Status` type defines a logical error model that is suitable for different
+// programming environments, including REST APIs and RPC APIs. It is used by
+// [gRPC](https://github.com/grpc). The error model is designed to be:
+//
+// - Simple to use and understand for most users
+// - Flexible enough to meet unexpected needs
+//
+// # Overview
+//
+// The `Status` message contains three pieces of data: error code, error message,
+// and error details. The error code should be an enum value of
+// [google.rpc.Code][google.rpc.Code], but it may accept additional error codes if needed.  The
+// error message should be a developer-facing English message that helps
+// developers *understand* and *resolve* the error. If a localized user-facing
+// error message is needed, put the localized message in the error details or
+// localize it in the client. The optional error details may contain arbitrary
+// information about the error. There is a predefined set of error detail types
+// in the package `google.rpc` which can be used for common error conditions.
+//
+// # Language mapping
+//
+// The `Status` message is the logical representation of the error model, but it
+// is not necessarily the actual wire format. When the `Status` message is
+// exposed in different client libraries and different wire protocols, it can be
+// mapped differently. For example, it will likely be mapped to some exceptions
+// in Java, but more likely mapped to some error codes in C.
+//
+// # Other uses
+//
+// The error model and the `Status` message can be used in a variety of
+// environments, either with or without APIs, to provide a
+// consistent developer experience across different environments.
+//
+// Example uses of this error model include:
+//
+// - Partial errors. If a service needs to return partial errors to the client,
+//     it may embed the `Status` in the normal response to indicate the partial
+//     errors.
+//
+// - Workflow errors. A typical workflow has multiple steps. Each step may
+//     have a `Status` message for error reporting purpose.
+//
+// - Batch operations. If a client uses batch request and batch response, the
+//     `Status` message should be used directly inside batch response, one for
+//     each error sub-response.
+//
+// - Asynchronous operations. If an API call embeds asynchronous operation
+//     results in its response, the status of those operations should be
+//     represented directly using the `Status` message.
+//
+// - Logging. If some API errors are stored in logs, the message `Status` could
+//     be used directly after any stripping needed for security/privacy reasons.
+type Status struct {
+	// The status code, which should be an enum value of [google.rpc.Code][google.rpc.Code].
+	Code int32 `protobuf:"varint,1,opt,name=code" json:"code,omitempty"`
+	// A developer-facing error message, which should be in English. Any
+	// user-facing error message should be localized and sent in the
+	// [google.rpc.Status.details][google.rpc.Status.details] field, or localized by the client.
+	Message string `protobuf:"bytes,2,opt,name=message" json:"message,omitempty"`
+	// A list of messages that carry the error details.  There will be a
+	// common set of message types for APIs to use.
+	Details []*google_protobuf.Any `protobuf:"bytes,3,rep,name=details" json:"details,omitempty"`
+}
+
+func (m *Status) Reset()                    { *m = Status{} }
+func (m *Status) String() string            { return proto.CompactTextString(m) }
+func (*Status) ProtoMessage()               {}
+func (*Status) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{0} }
+
+func (m *Status) GetCode() int32 {
+	if m != nil {
+		return m.Code
+	}
+	return 0
+}
+
+func (m *Status) GetMessage() string {
+	if m != nil {
+		return m.Message
+	}
+	return ""
+}
+
+func (m *Status) GetDetails() []*google_protobuf.Any {
+	if m != nil {
+		return m.Details
+	}
+	return nil
+}
+
+func init() {
+	proto.RegisterType((*Status)(nil), "google.rpc.Status")
+}
+
+func init() { proto.RegisterFile("google/rpc/status.proto", fileDescriptor0) }
+
+var fileDescriptor0 = []byte{
+	// 209 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0x12, 0x4f, 0xcf, 0xcf, 0x4f,
+	0xcf, 0x49, 0xd5, 0x2f, 0x2a, 0x48, 0xd6, 0x2f, 0x2e, 0x49, 0x2c, 0x29, 0x2d, 0xd6, 0x2b, 0x28,
+	0xca, 0x2f, 0xc9, 0x17, 0xe2, 0x82, 0x48, 0xe8, 0x15, 0x15, 0x24, 0x4b, 0x49, 0x42, 0x15, 0x81,
+	0x65, 0x92, 0x4a, 0xd3, 0xf4, 0x13, 0xf3, 0x2a, 0x21, 0xca, 0x94, 0xd2, 0xb8, 0xd8, 0x82, 0xc1,
+	0xda, 0x84, 0x84, 0xb8, 0x58, 0x92, 0xf3, 0x53, 0x52, 0x25, 0x18, 0x15, 0x18, 0x35, 0x58, 0x83,
+	0xc0, 0x6c, 0x21, 0x09, 0x2e, 0xf6, 0xdc, 0xd4, 0xe2, 0xe2, 0xc4, 0xf4, 0x54, 0x09, 0x26, 0x05,
+	0x46, 0x0d, 0xce, 0x20, 0x18, 0x57, 0x48, 0x8f, 0x8b, 0x3d, 0x25, 0xb5, 0x24, 0x31, 0x33, 0xa7,
+	0x58, 0x82, 0x59, 0x81, 0x59, 0x83, 0xdb, 0x48, 0x44, 0x0f, 0x6a, 0x21, 0xcc, 0x12, 0x3d, 0xc7,
+	0xbc, 0xca, 0x20, 0x98, 0x22, 0xa7, 0x38, 0x2e, 0xbe, 0xe4, 0xfc, 0x5c, 0x3d, 0x84, 0xa3, 0x9c,
+	0xb8, 0x21, 0xf6, 0x06, 0x80, 0x94, 0x07, 0x30, 0x46, 0x99, 0x43, 0xa5, 0xd2, 0xf3, 0x73, 0x12,
+	0xf3, 0xd2, 0xf5, 0xf2, 0x8b, 0xd2, 0xf5, 0xd3, 0x53, 0xf3, 0xc0, 0x86, 0xe9, 0x43, 0xa4, 0x12,
+	0x0b, 0x32, 0x8b, 0x91, 0xfc, 0x69, 0x0d, 0xa1, 0x16, 0x31, 0x31, 0x07, 0x05, 0x38, 0x27, 0xb1,
+	0x81, 0x55, 0x1a, 0x03, 0x02, 0x00, 0x00, 0xff, 0xff, 0xa4, 0x53, 0xf0, 0x7c, 0x10, 0x01, 0x00,
+	0x00,
+}

vendor/google.golang.org/genproto/regen.go

@@ -0,0 +1,123 @@
+// Copyright 2016 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build ignore
+
+// Regen.go regenerates the genproto repository.
+//
+// Regen.go recursively walks through each directory named by given arguments,
+// looking for all .proto files. (Symlinks are not followed.)
+// If the pkg_prefix flag is not an empty string,
+// any proto file without `go_package` option
+// or whose option does not begin with the prefix is ignored.
+// Protoc is executed on remaining files,
+// one invocation per set of files declaring the same Go package.
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+var goPkgOptRe = regexp.MustCompile(`(?m)^option go_package = (.*);`)
+
+func usage() {
+	fmt.Fprintln(os.Stderr, `usage: go run regen.go -go_out=path/to/output [-pkg_prefix=pkg/prefix] roots...
+
+Most users will not need to run this file directly.
+To regenerate this repository, run regen.sh instead.`)
+	flag.PrintDefaults()
+}
+
+func main() {
+	goOutDir := flag.String("go_out", "", "go_out argument to pass to protoc-gen-go")
+	pkgPrefix := flag.String("pkg_prefix", "", "only include proto files with go_package starting with this prefix")
+	flag.Usage = usage
+	flag.Parse()
+
+	if *goOutDir == "" {
+		log.Fatal("need go_out flag")
+	}
+
+	pkgFiles := make(map[string][]string)
+	walkFn := func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		if !info.Mode().IsRegular() || !strings.HasSuffix(path, ".proto") {
+			return nil
+		}
+		pkg, err := goPkg(path)
+		if err != nil {
+			return err
+		}
+		pkgFiles[pkg] = append(pkgFiles[pkg], path)
+		return nil
+	}
+	for _, root := range flag.Args() {
+		if err := filepath.Walk(root, walkFn); err != nil {
+			log.Fatal(err)
+		}
+	}
+	for pkg, fnames := range pkgFiles {
+		if !strings.HasPrefix(pkg, *pkgPrefix) {
+			continue
+		}
+		if out, err := protoc(*goOutDir, flag.Args(), fnames); err != nil {
+			log.Fatalf("error executing protoc: %s\n%s", err, out)
+		}
+	}
+}
+
+// goPkg reports the import path declared in the given file's
+// `go_package` option. If the option is missing, goPkg returns empty string.
+func goPkg(fname string) (string, error) {
+	content, err := ioutil.ReadFile(fname)
+	if err != nil {
+		return "", err
+	}
+
+	var pkgName string
+	if match := goPkgOptRe.FindSubmatch(content); len(match) > 0 {
+		pn, err := strconv.Unquote(string(match[1]))
+		if err != nil {
+			return "", err
+		}
+		pkgName = pn
+	}
+	if p := strings.IndexRune(pkgName, ';'); p > 0 {
+		pkgName = pkgName[:p]
+	}
+	return pkgName, nil
+}
+
+// protoc executes the "protoc" command on files named in fnames,
+// passing go_out and include flags specified in goOut and includes respectively.
+// protoc returns combined output from stdout and stderr.
+func protoc(goOut string, includes, fnames []string) ([]byte, error) {
+	args := []string{"--go_out=plugins=grpc:" + goOut}
+	for _, inc := range includes {
+		args = append(args, "-I", inc)
+	}
+	args = append(args, fnames...)
+	return exec.Command("protoc", args...).CombinedOutput()
+}

vendor/google.golang.org/grpc/backoff.go

@@ -58,7 +58,7 @@ func setDefaults(bc *BackoffConfig) {
 	}
 }
 
-func (bc BackoffConfig) backoff(retries int) (t time.Duration) {
+func (bc BackoffConfig) backoff(retries int) time.Duration {
 	if retries == 0 {
 		return bc.baseDelay
 	}

vendor/google.golang.org/grpc/balancer.go

@@ -38,6 +38,7 @@ import (
 	"sync"
 
 	"golang.org/x/net/context"
+	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/grpclog"
 	"google.golang.org/grpc/naming"
@@ -315,7 +316,7 @@ func (rr *roundRobin) Get(ctx context.Context, opts BalancerGetOptions) (addr Ad
 	if !opts.BlockingWait {
 		if len(rr.addrs) == 0 {
 			rr.mu.Unlock()
-			err = fmt.Errorf("there is no address available")
+			err = Errorf(codes.Unavailable, "there is no address available")
 			return
 		}
 		// Returns the next addr on rr.addrs for failfast RPCs.

vendor/google.golang.org/grpc/call.go

@@ -36,12 +36,14 @@ package grpc
 import (
 	"bytes"
 	"io"
-	"math"
 	"time"
 
 	"golang.org/x/net/context"
 	"golang.org/x/net/trace"
 	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/peer"
+	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/transport"
 )
 
@@ -49,9 +51,9 @@ import (
 // On error, it returns the error and indicates whether the call should be retried.
 //
 // TODO(zhaoq): Check whether the received message sequence is valid.
-func recvResponse(dopts dialOptions, t transport.ClientTransport, c *callInfo, stream *transport.Stream, reply interface{}) error {
+// TODO ctx is used for stats collection and processing. It is the context passed from the application.
+func recvResponse(ctx context.Context, dopts dialOptions, t transport.ClientTransport, c *callInfo, stream *transport.Stream, reply interface{}) (err error) {
 	// Try to acquire header metadata from the server if there is any.
-	var err error
 	defer func() {
 		if err != nil {
 			if _, ok := err.(transport.ConnectionError); !ok {
@@ -61,23 +63,37 @@ func recvResponse(dopts dialOptions, t transport.ClientTransport, c *callInfo, s
 	}()
 	c.headerMD, err = stream.Header()
 	if err != nil {
-		return err
+		return
 	}
 	p := &parser{r: stream}
+	var inPayload *stats.InPayload
+	if dopts.copts.StatsHandler != nil {
+		inPayload = &stats.InPayload{
+			Client: true,
+		}
+	}
 	for {
-		if err = recv(p, dopts.codec, stream, dopts.dc, reply, math.MaxInt32); err != nil {
+		if err = recv(p, dopts.codec, stream, dopts.dc, reply, dopts.maxMsgSize, inPayload); err != nil {
 			if err == io.EOF {
 				break
 			}
-			return err
+			return
 		}
 	}
+	if inPayload != nil && err == io.EOF && stream.Status().Code() == codes.OK {
+		// TODO in the current implementation, inTrailer may be handled before inPayload in some cases.
+		// Fix the order if necessary.
+		dopts.copts.StatsHandler.HandleRPC(ctx, inPayload)
+	}
 	c.trailerMD = stream.Trailer()
+	if peer, ok := peer.FromContext(stream.Context()); ok {
+		c.peer = peer
+	}
 	return nil
 }
 
 // sendRequest writes out various information of an RPC such as Context and Message.
-func sendRequest(ctx context.Context, codec Codec, compressor Compressor, callHdr *transport.CallHdr, t transport.ClientTransport, args interface{}, opts *transport.Options) (_ *transport.Stream, err error) {
+func sendRequest(ctx context.Context, dopts dialOptions, compressor Compressor, callHdr *transport.CallHdr, t transport.ClientTransport, args interface{}, opts *transport.Options) (_ *transport.Stream, err error) {
 	stream, err := t.NewStream(ctx, callHdr)
 	if err != nil {
 		return nil, err
@@ -90,15 +106,27 @@ func sendRequest(ctx context.Context, codec Codec, compressor Compressor, callHd
 			}
 		}
 	}()
-	var cbuf *bytes.Buffer
+	var (
+		cbuf       *bytes.Buffer
+		outPayload *stats.OutPayload
+	)
 	if compressor != nil {
 		cbuf = new(bytes.Buffer)
 	}
-	outBuf, err := encode(codec, args, compressor, cbuf)
+	if dopts.copts.StatsHandler != nil {
+		outPayload = &stats.OutPayload{
+			Client: true,
+		}
+	}
+	outBuf, err := encode(dopts.codec, args, compressor, cbuf, outPayload)
 	if err != nil {
 		return nil, Errorf(codes.Internal, "grpc: %v", err)
 	}
 	err = t.Write(stream, outBuf, opts)
+	if err == nil && outPayload != nil {
+		outPayload.SentTime = time.Now()
+		dopts.copts.StatsHandler.HandleRPC(ctx, outPayload)
+	}
 	// t.NewStream(...) could lead to an early rejection of the RPC (e.g., the service/method
 	// does not exist.) so that t.Write could get io.EOF from wait(...). Leave the following
 	// recvResponse to get the final status.
@@ -119,8 +147,16 @@ func Invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 	return invoke(ctx, method, args, reply, cc, opts...)
 }
 
-func invoke(ctx context.Context, method string, args, reply interface{}, cc *ClientConn, opts ...CallOption) (err error) {
+func invoke(ctx context.Context, method string, args, reply interface{}, cc *ClientConn, opts ...CallOption) (e error) {
 	c := defaultCallInfo
+	if mc, ok := cc.getMethodConfig(method); ok {
+		c.failFast = !mc.WaitForReady
+		if mc.Timeout > 0 {
+			var cancel context.CancelFunc
+			ctx, cancel = context.WithTimeout(ctx, mc.Timeout)
+			defer cancel()
+		}
+	}
 	for _, o := range opts {
 		if err := o.before(&c); err != nil {
 			return toRPCErr(err)
@@ -141,12 +177,32 @@ func invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 		c.traceInfo.tr.LazyLog(&c.traceInfo.firstLine, false)
 		// TODO(dsymonds): Arrange for c.traceInfo.firstLine.remoteAddr to be set.
 		defer func() {
-			if err != nil {
-				c.traceInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true)
+			if e != nil {
+				c.traceInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{e}}, true)
 				c.traceInfo.tr.SetError()
 			}
 		}()
 	}
+	sh := cc.dopts.copts.StatsHandler
+	if sh != nil {
+		ctx = sh.TagRPC(ctx, &stats.RPCTagInfo{FullMethodName: method})
+		begin := &stats.Begin{
+			Client:    true,
+			BeginTime: time.Now(),
+			FailFast:  c.failFast,
+		}
+		sh.HandleRPC(ctx, begin)
+	}
+	defer func() {
+		if sh != nil {
+			end := &stats.End{
+				Client:  true,
+				EndTime: time.Now(),
+				Error:   e,
+			}
+			sh.HandleRPC(ctx, end)
+		}
+	}()
 	topts := &transport.Options{
 		Last:  true,
 		Delay: false,
@@ -168,13 +224,14 @@ func invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 		if cc.dopts.cp != nil {
 			callHdr.SendCompress = cc.dopts.cp.Type()
 		}
+
 		gopts := BalancerGetOptions{
 			BlockingWait: !c.failFast,
 		}
 		t, put, err = cc.getTransport(ctx, gopts)
 		if err != nil {
 			// TODO(zhaoq): Probably revisit the error handling.
-			if _, ok := err.(*rpcError); ok {
+			if _, ok := status.FromError(err); ok {
 				return err
 			}
 			if err == errConnClosing || err == errConnUnavailable {
@@ -189,7 +246,7 @@ func invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 		if c.traceInfo.tr != nil {
 			c.traceInfo.tr.LazyLog(&payload{sent: true, msg: args}, true)
 		}
-		stream, err = sendRequest(ctx, cc.dopts.codec, cc.dopts.cp, callHdr, t, args, topts)
+		stream, err = sendRequest(ctx, cc.dopts, cc.dopts.cp, callHdr, t, args, topts)
 		if err != nil {
 			if put != nil {
 				put()
@@ -206,7 +263,7 @@ func invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 			}
 			return toRPCErr(err)
 		}
-		err = recvResponse(cc.dopts, t, &c, stream, reply)
+		err = recvResponse(ctx, cc.dopts, t, &c, stream, reply)
 		if err != nil {
 			if put != nil {
 				put()
@@ -228,6 +285,6 @@ func invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 			put()
 			put = nil
 		}
-		return Errorf(stream.StatusCode(), "%s", stream.StatusDesc())
+		return stream.Status().Err()
 	}
 }

vendor/google.golang.org/grpc/clientconn.go

@@ -36,8 +36,8 @@ package grpc
 import (
 	"errors"
 	"fmt"
+	"math"
 	"net"
-	"strings"
 	"sync"
 	"time"
 
@@ -45,6 +45,8 @@ import (
 	"golang.org/x/net/trace"
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/keepalive"
+	"google.golang.org/grpc/stats"
 	"google.golang.org/grpc/transport"
 )
 
@@ -54,6 +56,8 @@ var (
 	ErrClientConnClosing = errors.New("grpc: the client connection is closing")
 	// ErrClientConnTimeout indicates that the ClientConn cannot establish the
 	// underlying connections within the specified timeout.
+	// DEPRECATED: Please use context.DeadlineExceeded instead. This error will be
+	// removed in Q1 2017.
 	ErrClientConnTimeout = errors.New("grpc: timed out when dialing")
 
 	// errNoTransportSecurity indicates that there is no transport security
@@ -75,7 +79,6 @@ var (
 	errConnClosing = errors.New("grpc: the connection is closing")
 	// errConnUnavailable indicates that the connection is unavailable.
 	errConnUnavailable = errors.New("grpc: the connection is unavailable")
-	errNoAddr          = errors.New("grpc: there is no address available to dial")
 	// minimum time to give a connection to complete
 	minConnectTimeout = 20 * time.Second
 )
@@ -83,22 +86,33 @@ var (
 // dialOptions configure a Dial call. dialOptions are set by the DialOption
 // values passed to Dial.
 type dialOptions struct {
-	unaryInt  UnaryClientInterceptor
-	streamInt StreamClientInterceptor
-	codec     Codec
-	cp        Compressor
-	dc        Decompressor
-	bs        backoffStrategy
-	balancer  Balancer
-	block     bool
-	insecure  bool
-	timeout   time.Duration
-	copts     transport.ConnectOptions
+	unaryInt   UnaryClientInterceptor
+	streamInt  StreamClientInterceptor
+	codec      Codec
+	cp         Compressor
+	dc         Decompressor
+	bs         backoffStrategy
+	balancer   Balancer
+	block      bool
+	insecure   bool
+	timeout    time.Duration
+	scChan     <-chan ServiceConfig
+	copts      transport.ConnectOptions
+	maxMsgSize int
 }
 
+const defaultClientMaxMsgSize = math.MaxInt32
+
 // DialOption configures how we set up the connection.
 type DialOption func(*dialOptions)
 
+// WithMaxMsgSize returns a DialOption which sets the maximum message size the client can receive.
+func WithMaxMsgSize(s int) DialOption {
+	return func(o *dialOptions) {
+		o.maxMsgSize = s
+	}
+}
+
 // WithCodec returns a DialOption which sets a codec for message marshaling and unmarshaling.
 func WithCodec(c Codec) DialOption {
 	return func(o *dialOptions) {
@@ -129,6 +143,13 @@ func WithBalancer(b Balancer) DialOption {
 	}
 }
 
+// WithServiceConfig returns a DialOption which has a channel to read the service configuration.
+func WithServiceConfig(c <-chan ServiceConfig) DialOption {
+	return func(o *dialOptions) {
+		o.scChan = c
+	}
+}
+
 // WithBackoffMaxDelay configures the dialer to use the provided maximum delay
 // when backing off after failed connection attempts.
 func WithBackoffMaxDelay(md time.Duration) DialOption {
@@ -199,6 +220,8 @@ func WithTimeout(d time.Duration) DialOption {
 }
 
 // WithDialer returns a DialOption that specifies a function to use for dialing network addresses.
+// If FailOnNonTempDialError() is set to true, and an error is returned by f, gRPC checks the error's
+// Temporary() method to decide if it should try to reconnect to the network address.
 func WithDialer(f func(string, time.Duration) (net.Conn, error)) DialOption {
 	return func(o *dialOptions) {
 		o.copts.Dialer = func(ctx context.Context, addr string) (net.Conn, error) {
@@ -210,6 +233,25 @@ func WithDialer(f func(string, time.Duration) (net.Conn, error)) DialOption {
 	}
 }
 
+// WithStatsHandler returns a DialOption that specifies the stats handler
+// for all the RPCs and underlying network connections in this ClientConn.
+func WithStatsHandler(h stats.Handler) DialOption {
+	return func(o *dialOptions) {
+		o.copts.StatsHandler = h
+	}
+}
+
+// FailOnNonTempDialError returns a DialOption that specified if gRPC fails on non-temporary dial errors.
+// If f is true, and dialer returns a non-temporary error, gRPC will fail the connection to the network
+// address and won't try to reconnect.
+// The default value of FailOnNonTempDialError is false.
+// This is an EXPERIMENTAL API.
+func FailOnNonTempDialError(f bool) DialOption {
+	return func(o *dialOptions) {
+		o.copts.FailOnNonTempDialError = f
+	}
+}
+
 // WithUserAgent returns a DialOption that specifies a user agent string for all the RPCs.
 func WithUserAgent(s string) DialOption {
 	return func(o *dialOptions) {
@@ -217,6 +259,13 @@ func WithUserAgent(s string) DialOption {
 	}
 }
 
+// WithKeepaliveParams returns a DialOption that specifies keepalive paramaters for the client transport.
+func WithKeepaliveParams(kp keepalive.ClientParameters) DialOption {
+	return func(o *dialOptions) {
+		o.copts.KeepaliveParams = kp
+	}
+}
+
 // WithUnaryInterceptor returns a DialOption that specifies the interceptor for unary RPCs.
 func WithUnaryInterceptor(f UnaryClientInterceptor) DialOption {
 	return func(o *dialOptions) {
@@ -231,6 +280,15 @@ func WithStreamInterceptor(f StreamClientInterceptor) DialOption {
 	}
 }
 
+// WithAuthority returns a DialOption that specifies the value to be used as
+// the :authority pseudo-header. This value only works with WithInsecure and
+// has no effect if TransportCredentials are present.
+func WithAuthority(a string) DialOption {
+	return func(o *dialOptions) {
+		o.copts.Authority = a
+	}
+}
+
 // Dial creates a client connection to the given target.
 func Dial(target string, opts ...DialOption) (*ClientConn, error) {
 	return DialContext(context.Background(), target, opts...)
@@ -247,6 +305,25 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		conns:  make(map[Address]*addrConn),
 	}
 	cc.ctx, cc.cancel = context.WithCancel(context.Background())
+	cc.dopts.maxMsgSize = defaultClientMaxMsgSize
+	for _, opt := range opts {
+		opt(&cc.dopts)
+	}
+	cc.mkp = cc.dopts.copts.KeepaliveParams
+
+	grpcUA := "grpc-go/" + Version
+	if cc.dopts.copts.UserAgent != "" {
+		cc.dopts.copts.UserAgent += " " + grpcUA
+	} else {
+		cc.dopts.copts.UserAgent = grpcUA
+	}
+
+	if cc.dopts.timeout > 0 {
+		var cancel context.CancelFunc
+		ctx, cancel = context.WithTimeout(ctx, cc.dopts.timeout)
+		defer cancel()
+	}
+
 	defer func() {
 		select {
 		case <-ctx.Done():
@@ -259,10 +336,17 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		}
 	}()
 
-	for _, opt := range opts {
-		opt(&cc.dopts)
+	if cc.dopts.scChan != nil {
+		// Wait for the initial service config.
+		select {
+		case sc, ok := <-cc.dopts.scChan:
+			if ok {
+				cc.sc = sc
+			}
+		case <-ctx.Done():
+			return nil, ctx.Err()
+		}
 	}
-
 	// Set defaults.
 	if cc.dopts.codec == nil {
 		cc.dopts.codec = protoCodec{}
@@ -273,21 +357,18 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 	creds := cc.dopts.copts.TransportCredentials
 	if creds != nil && creds.Info().ServerName != "" {
 		cc.authority = creds.Info().ServerName
+	} else if cc.dopts.insecure && cc.dopts.copts.Authority != "" {
+		cc.authority = cc.dopts.copts.Authority
 	} else {
-		colonPos := strings.LastIndex(target, ":")
-		if colonPos == -1 {
-			colonPos = len(target)
-		}
-		cc.authority = target[:colonPos]
+		cc.authority = target
 	}
-	var ok bool
 	waitC := make(chan error, 1)
 	go func() {
-		var addrs []Address
-		if cc.dopts.balancer == nil {
-			// Connect to target directly if balancer is nil.
-			addrs = append(addrs, Address{Addr: target})
-		} else {
+		defer close(waitC)
+		if cc.dopts.balancer == nil && cc.sc.LB != nil {
+			cc.dopts.balancer = cc.sc.LB
+		}
+		if cc.dopts.balancer != nil {
 			var credsClone credentials.TransportCredentials
 			if creds != nil {
 				credsClone = creds.Clone()
@@ -300,29 +381,23 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 				return
 			}
 			ch := cc.dopts.balancer.Notify()
-			if ch == nil {
-				// There is no name resolver installed.
-				addrs = append(addrs, Address{Addr: target})
-			} else {
-				addrs, ok = <-ch
-				if !ok || len(addrs) == 0 {
-					waitC <- errNoAddr
-					return
+			if ch != nil {
+				if cc.dopts.block {
+					doneChan := make(chan struct{})
+					go cc.lbWatcher(doneChan)
+					<-doneChan
+				} else {
+					go cc.lbWatcher(nil)
 				}
-			}
-		}
-		for _, a := range addrs {
-			if err := cc.resetAddrConn(a, false, nil); err != nil {
-				waitC <- err
 				return
 			}
 		}
-		close(waitC)
+		// No balancer, or no resolver within the balancer.  Connect directly.
+		if err := cc.resetAddrConn(Address{Addr: target}, cc.dopts.block, nil); err != nil {
+			waitC <- err
+			return
+		}
 	}()
-	var timeoutCh <-chan time.Time
-	if cc.dopts.timeout > 0 {
-		timeoutCh = time.After(cc.dopts.timeout)
-	}
 	select {
 	case <-ctx.Done():
 		return nil, ctx.Err()
@@ -330,14 +405,12 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		if err != nil {
 			return nil, err
 		}
-	case <-timeoutCh:
-		return nil, ErrClientConnTimeout
 	}
-	// If balancer is nil or balancer.Notify() is nil, ok will be false here.
-	// The lbWatcher goroutine will not be created.
-	if ok {
-		go cc.lbWatcher()
+
+	if cc.dopts.scChan != nil {
+		go cc.scWatcher()
 	}
+
 	return cc, nil
 }
 
@@ -384,10 +457,16 @@ type ClientConn struct {
 	dopts     dialOptions
 
 	mu    sync.RWMutex
+	sc    ServiceConfig
 	conns map[Address]*addrConn
+	// Keepalive parameter can be udated if a GoAway is received.
+	mkp keepalive.ClientParameters
 }
 
-func (cc *ClientConn) lbWatcher() {
+// lbWatcher watches the Notify channel of the balancer in cc and manages
+// connections accordingly.  If doneChan is not nil, it is closed after the
+// first successfull connection is made.
+func (cc *ClientConn) lbWatcher(doneChan chan struct{}) {
 	for addrs := range cc.dopts.balancer.Notify() {
 		var (
 			add []Address   // Addresses need to setup connections.
@@ -414,7 +493,15 @@ func (cc *ClientConn) lbWatcher() {
 		}
 		cc.mu.Unlock()
 		for _, a := range add {
-			cc.resetAddrConn(a, true, nil)
+			if doneChan != nil {
+				err := cc.resetAddrConn(a, true, nil)
+				if err == nil {
+					close(doneChan)
+					doneChan = nil
+				}
+			} else {
+				cc.resetAddrConn(a, false, nil)
+			}
 		}
 		for _, c := range del {
 			c.tearDown(errConnDrain)
@@ -422,15 +509,36 @@ func (cc *ClientConn) lbWatcher() {
 	}
 }
 
+func (cc *ClientConn) scWatcher() {
+	for {
+		select {
+		case sc, ok := <-cc.dopts.scChan:
+			if !ok {
+				return
+			}
+			cc.mu.Lock()
+			// TODO: load balance policy runtime change is ignored.
+			// We may revist this decision in the future.
+			cc.sc = sc
+			cc.mu.Unlock()
+		case <-cc.ctx.Done():
+			return
+		}
+	}
+}
+
 // resetAddrConn creates an addrConn for addr and adds it to cc.conns.
 // If there is an old addrConn for addr, it will be torn down, using tearDownErr as the reason.
 // If tearDownErr is nil, errConnDrain will be used instead.
-func (cc *ClientConn) resetAddrConn(addr Address, skipWait bool, tearDownErr error) error {
+func (cc *ClientConn) resetAddrConn(addr Address, block bool, tearDownErr error) error {
 	ac := &addrConn{
 		cc:    cc,
 		addr:  addr,
 		dopts: cc.dopts,
 	}
+	cc.mu.RLock()
+	ac.dopts.copts.KeepaliveParams = cc.mkp
+	cc.mu.RUnlock()
 	ac.ctx, ac.cancel = context.WithCancel(cc.ctx)
 	ac.stateCV = sync.NewCond(&ac.mu)
 	if EnableTracing {
@@ -475,8 +583,7 @@ func (cc *ClientConn) resetAddrConn(addr Address, skipWait bool, tearDownErr err
 			stale.tearDown(tearDownErr)
 		}
 	}
-	// skipWait may overwrite the decision in ac.dopts.block.
-	if ac.dopts.block && !skipWait {
+	if block {
 		if err := ac.resetTransport(false); err != nil {
 			if err != errConnClosing {
 				// Tear down ac and delete it from cc.conns.
@@ -509,6 +616,14 @@ func (cc *ClientConn) resetAddrConn(addr Address, skipWait bool, tearDownErr err
 	return nil
 }
 
+// TODO: Avoid the locking here.
+func (cc *ClientConn) getMethodConfig(method string) (m MethodConfig, ok bool) {
+	cc.mu.RLock()
+	defer cc.mu.RUnlock()
+	m, ok = cc.sc.Methods[method]
+	return
+}
+
 func (cc *ClientConn) getTransport(ctx context.Context, opts BalancerGetOptions) (transport.ClientTransport, func(), error) {
 	var (
 		ac  *addrConn
@@ -605,6 +720,20 @@ type addrConn struct {
 	tearDownErr error
 }
 
+// adjustParams updates parameters used to create transports upon
+// receiving a GoAway.
+func (ac *addrConn) adjustParams(r transport.GoAwayReason) {
+	switch r {
+	case transport.TooManyPings:
+		v := 2 * ac.dopts.copts.KeepaliveParams.Time
+		ac.cc.mu.Lock()
+		if v > ac.cc.mkp.Time {
+			ac.cc.mkp.Time = v
+		}
+		ac.cc.mu.Unlock()
+	}
+}
+
 // printf records an event in ac's event log, unless ac has been closed.
 // REQUIRES ac.mu is held.
 func (ac *addrConn) printf(format string, a ...interface{}) {
@@ -684,7 +813,13 @@ func (ac *addrConn) resetTransport(closeTransport bool) error {
 		}
 		ctx, cancel := context.WithTimeout(ac.ctx, timeout)
 		connectTime := time.Now()
-		newTransport, err := transport.NewClientTransport(ctx, ac.addr.Addr, ac.dopts.copts)
+		sinfo := transport.TargetInfo{
+			Addr:     ac.addr.Addr,
+			Metadata: ac.addr.Metadata,
+		}
+		newTransport, err := transport.NewClientTransport(ctx, sinfo, ac.dopts.copts)
+		// Don't call cancel in success path due to a race in Go 1.6:
+		// https://github.com/golang/go/issues/15078.
 		if err != nil {
 			cancel()
 
@@ -755,6 +890,7 @@ func (ac *addrConn) transportMonitor() {
 			}
 			return
 		case <-t.GoAway():
+			ac.adjustParams(t.GetGoAwayReason())
 			// If GoAway happens without any network I/O error, ac is closed without shutting down the
 			// underlying transport (the transport will be closed when all the pending RPCs finished or
 			// failed.).
@@ -763,9 +899,9 @@ func (ac *addrConn) transportMonitor() {
 			// In both cases, a new ac is created.
 			select {
 			case <-t.Error():
-				ac.cc.resetAddrConn(ac.addr, true, errNetworkIO)
+				ac.cc.resetAddrConn(ac.addr, false, errNetworkIO)
 			default:
-				ac.cc.resetAddrConn(ac.addr, true, errConnDrain)
+				ac.cc.resetAddrConn(ac.addr, false, errConnDrain)
 			}
 			return
 		case <-t.Error():
@@ -774,7 +910,8 @@ func (ac *addrConn) transportMonitor() {
 				t.Close()
 				return
 			case <-t.GoAway():
-				ac.cc.resetAddrConn(ac.addr, true, errNetworkIO)
+				ac.adjustParams(t.GetGoAwayReason())
+				ac.cc.resetAddrConn(ac.addr, false, errNetworkIO)
 				return
 			default:
 			}
@@ -803,7 +940,7 @@ func (ac *addrConn) transportMonitor() {
 }
 
 // wait blocks until i) the new transport is up or ii) ctx is done or iii) ac is closed or
-// iv) transport is in TransientFailure and there's no balancer/failfast is true.
+// iv) transport is in TransientFailure and there is a balancer/failfast is true.
 func (ac *addrConn) wait(ctx context.Context, hasBalancer, failfast bool) (transport.ClientTransport, error) {
 	for {
 		ac.mu.Lock()

vendor/google.golang.org/grpc/codec.go

@@ -0,0 +1,118 @@
+/*
+*
+ * Copyright 2014, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+*/
+
+package grpc
+
+import (
+	"math"
+	"sync"
+
+	"github.com/golang/protobuf/proto"
+)
+
+// Codec defines the interface gRPC uses to encode and decode messages.
+// Note that implementations of this interface must be thread safe;
+// a Codec's methods can be called from concurrent goroutines.
+type Codec interface {
+	// Marshal returns the wire format of v.
+	Marshal(v interface{}) ([]byte, error)
+	// Unmarshal parses the wire format into v.
+	Unmarshal(data []byte, v interface{}) error
+	// String returns the name of the Codec implementation. The returned
+	// string will be used as part of content type in transmission.
+	String() string
+}
+
+// protoCodec is a Codec implementation with protobuf. It is the default codec for gRPC.
+type protoCodec struct {
+}
+
+type cachedProtoBuffer struct {
+	lastMarshaledSize uint32
+	proto.Buffer
+}
+
+func capToMaxInt32(val int) uint32 {
+	if val > math.MaxInt32 {
+		return uint32(math.MaxInt32)
+	}
+	return uint32(val)
+}
+
+func (p protoCodec) marshal(v interface{}, cb *cachedProtoBuffer) ([]byte, error) {
+	protoMsg := v.(proto.Message)
+	newSlice := make([]byte, 0, cb.lastMarshaledSize)
+
+	cb.SetBuf(newSlice)
+	cb.Reset()
+	if err := cb.Marshal(protoMsg); err != nil {
+		return nil, err
+	}
+	out := cb.Bytes()
+	cb.lastMarshaledSize = capToMaxInt32(len(out))
+	return out, nil
+}
+
+func (p protoCodec) Marshal(v interface{}) ([]byte, error) {
+	cb := protoBufferPool.Get().(*cachedProtoBuffer)
+	out, err := p.marshal(v, cb)
+
+	// put back buffer and lose the ref to the slice
+	cb.SetBuf(nil)
+	protoBufferPool.Put(cb)
+	return out, err
+}
+
+func (p protoCodec) Unmarshal(data []byte, v interface{}) error {
+	cb := protoBufferPool.Get().(*cachedProtoBuffer)
+	cb.SetBuf(data)
+	err := cb.Unmarshal(v.(proto.Message))
+	cb.SetBuf(nil)
+	protoBufferPool.Put(cb)
+	return err
+}
+
+func (protoCodec) String() string {
+	return "proto"
+}
+
+var (
+	protoBufferPool = &sync.Pool{
+		New: func() interface{} {
+			return &cachedProtoBuffer{
+				Buffer:            proto.Buffer{},
+				lastMarshaledSize: 16,
+			}
+		},
+	}
+)

vendor/google.golang.org/grpc/credentials/credentials.go

@@ -102,6 +102,10 @@ type TransportCredentials interface {
 	// authentication protocol on rawConn for clients. It returns the authenticated
 	// connection and the corresponding auth information about the connection.
 	// Implementations must use the provided context to implement timely cancellation.
+	// gRPC will try to reconnect if the error returned is a temporary error
+	// (io.EOF, context.DeadlineExceeded or err.Temporary() == true).
+	// If the returned error is a wrapper error, implementations should make sure that
+	// the error implements Temporary() to have the correct retry behaviors.
 	ClientHandshake(context.Context, string, net.Conn) (net.Conn, AuthInfo, error)
 	// ServerHandshake does the authentication handshake for servers. It returns
 	// the authenticated connection and the corresponding auth information about
@@ -165,9 +169,7 @@ func (c *tlsCreds) ClientHandshake(ctx context.Context, addr string, rawConn net
 	case <-ctx.Done():
 		return nil, nil, ctx.Err()
 	}
-	// TODO(zhaoq): Omit the auth info for client now. It is more for
-	// information than anything else.
-	return conn, nil, nil
+	return conn, TLSInfo{conn.ConnectionState()}, nil
 }
 
 func (c *tlsCreds) ServerHandshake(rawConn net.Conn) (net.Conn, AuthInfo, error) {

vendor/google.golang.org/grpc/credentials/credentials_util_go17.go

@@ -1,4 +1,5 @@
 // +build go1.7
+// +build !go1.8
 
 /*
  *
@@ -44,8 +45,6 @@ import (
 // contains a mutex and must not be copied.
 //
 // If cfg is nil, a new zero tls.Config is returned.
-//
-// TODO replace this function with official clone function.
 func cloneTLSConfig(cfg *tls.Config) *tls.Config {
 	if cfg == nil {
 		return &tls.Config{}

vendor/google.golang.org/grpc/credentials/credentials_util_go18.go

@@ -1,7 +1,8 @@
-// +build !go1.6
+// +build go1.8
 
 /*
- * Copyright 2016, Google Inc.
+ *
+ * Copyright 2017, Google Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -32,20 +33,21 @@
  *
  */
 
-package transport
+package credentials
 
 import (
-	"net"
-	"time"
-
-	"golang.org/x/net/context"
+	"crypto/tls"
 )
 
-// dialContext connects to the address on the named network.
-func dialContext(ctx context.Context, network, address string) (net.Conn, error) {
-	var dialer net.Dialer
-	if deadline, ok := ctx.Deadline(); ok {
-		dialer.Timeout = deadline.Sub(time.Now())
+// cloneTLSConfig returns a shallow clone of the exported
+// fields of cfg, ignoring the unexported sync.Once, which
+// contains a mutex and must not be copied.
+//
+// If cfg is nil, a new zero tls.Config is returned.
+func cloneTLSConfig(cfg *tls.Config) *tls.Config {
+	if cfg == nil {
+		return &tls.Config{}
 	}
-	return dialer.Dial(network, address)
+
+	return cfg.Clone()
 }

vendor/google.golang.org/grpc/credentials/credentials_util_pre_go17.go

@@ -44,8 +44,6 @@ import (
 // contains a mutex and must not be copied.
 //
 // If cfg is nil, a new zero tls.Config is returned.
-//
-// TODO replace this function with official clone function.
 func cloneTLSConfig(cfg *tls.Config) *tls.Config {
 	if cfg == nil {
 		return &tls.Config{}

vendor/google.golang.org/grpc/interceptor.go

@@ -40,7 +40,7 @@ import (
 // UnaryInvoker is called by UnaryClientInterceptor to complete RPCs.
 type UnaryInvoker func(ctx context.Context, method string, req, reply interface{}, cc *ClientConn, opts ...CallOption) error
 
-// UnaryClientInterceptor intercepts the execution of a unary RPC on the client. inovker is the handler to complete the RPC
+// UnaryClientInterceptor intercepts the execution of a unary RPC on the client. invoker is the handler to complete the RPC
 // and it is the responsibility of the interceptor to call it.
 // This is the EXPERIMENTAL API.
 type UnaryClientInterceptor func(ctx context.Context, method string, req, reply interface{}, cc *ClientConn, invoker UnaryInvoker, opts ...CallOption) error

vendor/google.golang.org/grpc/keepalive/keepalive.go

@@ -0,0 +1,80 @@
+/*
+ *
+ * Copyright 2017, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+// Package keepalive defines configurable parameters for point-to-point healthcheck.
+package keepalive
+
+import (
+	"time"
+)
+
+// ClientParameters is used to set keepalive parameters on the client-side.
+// These configure how the client will actively probe to notice when a connection broken
+// and to cause activity so intermediaries are aware the connection is still in use.
+// Make sure these parameters are set in coordination with the keepalive policy on the server,
+// as incompatible settings can result in closing of connection.
+type ClientParameters struct {
+	// After a duration of this time if the client doesn't see any activity it pings the server to see if the transport is still alive.
+	Time time.Duration // The current default value is infinity.
+	// After having pinged for keepalive check, the client waits for a duration of Timeout and if no activity is seen even after that
+	// the connection is closed.
+	Timeout time.Duration // The current default value is 20 seconds.
+	// If true, client runs keepalive checks even with no active RPCs.
+	PermitWithoutStream bool // false by default.
+}
+
+// ServerParameters is used to set keepalive and max-age parameters on the server-side.
+type ServerParameters struct {
+	// MaxConnectionIdle is a duration for the amount of time after which an idle connection would be closed by sending a GoAway.
+	// Idleness duration is defined since the most recent time the number of outstanding RPCs became zero or the connection establishment.
+	MaxConnectionIdle time.Duration // The current default value is infinity.
+	// MaxConnectionAge is a duration for the maximum amount of time a connection may exist before it will be closed by sending a GoAway.
+	// A random jitter of +/-10% will be added to MaxConnectionAge to spread out connection storms.
+	MaxConnectionAge time.Duration // The current default value is infinity.
+	// MaxConnectinoAgeGrace is an additive period after MaxConnectionAge after which the connection will be forcibly closed.
+	MaxConnectionAgeGrace time.Duration // The current default value is infinity.
+	// After a duration of this time if the server doesn't see any activity it pings the client to see if the transport is still alive.
+	Time time.Duration // The current default value is 2 hours.
+	// After having pinged for keepalive check, the server waits for a duration of Timeout and if no activity is seen even after that
+	// the connection is closed.
+	Timeout time.Duration // The current default value is 20 seconds.
+}
+
+// EnforcementPolicy is used to set keepalive enforcement policy on the server-side.
+// Server will close connection with a client that violates this policy.
+type EnforcementPolicy struct {
+	// MinTime is the minimum amount of time a client should wait before sending a keepalive ping.
+	MinTime time.Duration // The current default value is 5 minutes.
+	// If true, server expects keepalive pings even when there are no active streams(RPCs).
+	PermitWithoutStream bool // false by default.
+}

vendor/google.golang.org/grpc/metadata/metadata.go

@@ -32,6 +32,7 @@
  */
 
 // Package metadata define the structure of the metadata supported by gRPC library.
+// Please refer to http://www.grpc.io/docs/guides/wire.html for more information about custom-metadata.
 package metadata // import "google.golang.org/grpc/metadata"
 
 import (
@@ -82,6 +83,7 @@ func DecodeKeyValue(k, v string) (string, string, error) {
 type MD map[string][]string
 
 // New creates a MD from given key-value map.
+// Keys are automatically converted to lowercase. And for keys having "-bin" as suffix, their values will be applied Base64 encoding.
 func New(m map[string]string) MD {
 	md := MD{}
 	for k, v := range m {
@@ -93,6 +95,7 @@ func New(m map[string]string) MD {
 
 // Pairs returns an MD formed by the mapping of key, value ...
 // Pairs panics if len(kv) is odd.
+// Keys are automatically converted to lowercase. And for keys having "-bin" as suffix, their values will be appplied Base64 encoding.
 func Pairs(kv ...string) MD {
 	if len(kv)%2 == 1 {
 		panic(fmt.Sprintf("metadata: Pairs got the odd number of input pairs for metadata: %d", len(kv)))
@@ -133,15 +136,41 @@ func Join(mds ...MD) MD {
 	return out
 }
 
-type mdKey struct{}
+type mdIncomingKey struct{}
+type mdOutgoingKey struct{}
 
-// NewContext creates a new context with md attached.
+// NewContext is a wrapper for NewOutgoingContext(ctx, md).  Deprecated.
 func NewContext(ctx context.Context, md MD) context.Context {
-	return context.WithValue(ctx, mdKey{}, md)
+	return NewOutgoingContext(ctx, md)
 }
 
-// FromContext returns the MD in ctx if it exists.
+// NewIncomingContext creates a new context with incoming md attached.
+func NewIncomingContext(ctx context.Context, md MD) context.Context {
+	return context.WithValue(ctx, mdIncomingKey{}, md)
+}
+
+// NewOutgoingContext creates a new context with outgoing md attached.
+func NewOutgoingContext(ctx context.Context, md MD) context.Context {
+	return context.WithValue(ctx, mdOutgoingKey{}, md)
+}
+
+// FromContext is a wrapper for FromIncomingContext(ctx).  Deprecated.
 func FromContext(ctx context.Context) (md MD, ok bool) {
-	md, ok = ctx.Value(mdKey{}).(MD)
+	return FromIncomingContext(ctx)
+}
+
+// FromIncomingContext returns the incoming MD in ctx if it exists.  The
+// returned md should be immutable, writing to it may cause races.
+// Modification should be made to the copies of the returned md.
+func FromIncomingContext(ctx context.Context) (md MD, ok bool) {
+	md, ok = ctx.Value(mdIncomingKey{}).(MD)
+	return
+}
+
+// FromOutgoingContext returns the outgoing MD in ctx if it exists.  The
+// returned md should be immutable, writing to it may cause races.
+// Modification should be made to the copies of the returned md.
+func FromOutgoingContext(ctx context.Context) (md MD, ok bool) {
+	md, ok = ctx.Value(mdOutgoingKey{}).(MD)
 	return
 }

vendor/google.golang.org/grpc/rpc_util.go

@@ -37,45 +37,21 @@ import (
 	"bytes"
 	"compress/gzip"
 	"encoding/binary"
-	"fmt"
 	"io"
 	"io/ioutil"
 	"math"
 	"os"
+	"time"
 
-	"github.com/golang/protobuf/proto"
 	"golang.org/x/net/context"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/peer"
+	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/transport"
 )
 
-// Codec defines the interface gRPC uses to encode and decode messages.
-type Codec interface {
-	// Marshal returns the wire format of v.
-	Marshal(v interface{}) ([]byte, error)
-	// Unmarshal parses the wire format into v.
-	Unmarshal(data []byte, v interface{}) error
-	// String returns the name of the Codec implementation. The returned
-	// string will be used as part of content type in transmission.
-	String() string
-}
-
-// protoCodec is a Codec implementation with protobuf. It is the default codec for gRPC.
-type protoCodec struct{}
-
-func (protoCodec) Marshal(v interface{}) ([]byte, error) {
-	return proto.Marshal(v.(proto.Message))
-}
-
-func (protoCodec) Unmarshal(data []byte, v interface{}) error {
-	return proto.Unmarshal(data, v.(proto.Message))
-}
-
-func (protoCodec) String() string {
-	return "proto"
-}
-
 // Compressor defines the interface gRPC uses to compress a message.
 type Compressor interface {
 	// Do compresses p into w.
@@ -138,6 +114,7 @@ type callInfo struct {
 	failFast  bool
 	headerMD  metadata.MD
 	trailerMD metadata.MD
+	peer      *peer.Peer
 	traceInfo traceInfo // in trace.go
 }
 
@@ -181,12 +158,22 @@ func Trailer(md *metadata.MD) CallOption {
 	})
 }
 
+// Peer returns a CallOption that retrieves peer information for a
+// unary RPC.
+func Peer(peer *peer.Peer) CallOption {
+	return afterCall(func(c *callInfo) {
+		if c.peer != nil {
+			*peer = *c.peer
+		}
+	})
+}
+
 // FailFast configures the action to take when an RPC is attempted on broken
 // connections or unreachable servers. If failfast is true, the RPC will fail
 // immediately. Otherwise, the RPC client will block the call until a
 // connection is available (or the call is canceled or times out) and will retry
 // the call if it fails due to a transient error. Please refer to
-// https://github.com/grpc/grpc/blob/master/doc/fail_fast.md
+// https://github.com/grpc/grpc/blob/master/doc/fail_fast.md. Note: failFast is default to true.
 func FailFast(failFast bool) CallOption {
 	return beforeCall(func(c *callInfo) error {
 		c.failFast = failFast
@@ -255,9 +242,11 @@ func (p *parser) recvMsg(maxMsgSize int) (pf payloadFormat, msg []byte, err erro
 
 // encode serializes msg and prepends the message header. If msg is nil, it
 // generates the message header of 0 message length.
-func encode(c Codec, msg interface{}, cp Compressor, cbuf *bytes.Buffer) ([]byte, error) {
-	var b []byte
-	var length uint
+func encode(c Codec, msg interface{}, cp Compressor, cbuf *bytes.Buffer, outPayload *stats.OutPayload) ([]byte, error) {
+	var (
+		b      []byte
+		length uint
+	)
 	if msg != nil {
 		var err error
 		// TODO(zhaoq): optimize to reduce memory alloc and copying.
@@ -265,6 +254,12 @@ func encode(c Codec, msg interface{}, cp Compressor, cbuf *bytes.Buffer) ([]byte
 		if err != nil {
 			return nil, err
 		}
+		if outPayload != nil {
+			outPayload.Payload = msg
+			// TODO truncate large payload.
+			outPayload.Data = b
+			outPayload.Length = len(b)
+		}
 		if cp != nil {
 			if err := cp.Do(cbuf, b); err != nil {
 				return nil, err
@@ -295,6 +290,10 @@ func encode(c Codec, msg interface{}, cp Compressor, cbuf *bytes.Buffer) ([]byte
 	// Copy encoded msg to buf
 	copy(buf[5:], b)
 
+	if outPayload != nil {
+		outPayload.WireLength = len(buf)
+	}
+
 	return buf, nil
 }
 
@@ -311,11 +310,14 @@ func checkRecvPayload(pf payloadFormat, recvCompress string, dc Decompressor) er
 	return nil
 }
 
-func recv(p *parser, c Codec, s *transport.Stream, dc Decompressor, m interface{}, maxMsgSize int) error {
+func recv(p *parser, c Codec, s *transport.Stream, dc Decompressor, m interface{}, maxMsgSize int, inPayload *stats.InPayload) error {
 	pf, d, err := p.recvMsg(maxMsgSize)
 	if err != nil {
 		return err
 	}
+	if inPayload != nil {
+		inPayload.WireLength = len(d)
+	}
 	if err := checkRecvPayload(pf, s.RecvCompress(), dc); err != nil {
 		return err
 	}
@@ -333,91 +335,67 @@ func recv(p *parser, c Codec, s *transport.Stream, dc Decompressor, m interface{
 	if err := c.Unmarshal(d, m); err != nil {
 		return Errorf(codes.Internal, "grpc: failed to unmarshal the received message %v", err)
 	}
+	if inPayload != nil {
+		inPayload.RecvTime = time.Now()
+		inPayload.Payload = m
+		// TODO truncate large payload.
+		inPayload.Data = d
+		inPayload.Length = len(d)
+	}
 	return nil
 }
 
-// rpcError defines the status from an RPC.
-type rpcError struct {
-	code codes.Code
-	desc string
-}
-
-func (e *rpcError) Error() string {
-	return fmt.Sprintf("rpc error: code = %d desc = %s", e.code, e.desc)
-}
-
 // Code returns the error code for err if it was produced by the rpc system.
 // Otherwise, it returns codes.Unknown.
+//
+// Deprecated; use status.FromError and Code method instead.
 func Code(err error) codes.Code {
-	if err == nil {
-		return codes.OK
-	}
-	if e, ok := err.(*rpcError); ok {
-		return e.code
+	if s, ok := status.FromError(err); ok {
+		return s.Code()
 	}
 	return codes.Unknown
 }
 
 // ErrorDesc returns the error description of err if it was produced by the rpc system.
 // Otherwise, it returns err.Error() or empty string when err is nil.
+//
+// Deprecated; use status.FromError and Message method instead.
 func ErrorDesc(err error) string {
-	if err == nil {
-		return ""
-	}
-	if e, ok := err.(*rpcError); ok {
-		return e.desc
+	if s, ok := status.FromError(err); ok {
+		return s.Message()
 	}
 	return err.Error()
 }
 
 // Errorf returns an error containing an error code and a description;
 // Errorf returns nil if c is OK.
+//
+// Deprecated; use status.Errorf instead.
 func Errorf(c codes.Code, format string, a ...interface{}) error {
-	if c == codes.OK {
-		return nil
-	}
-	return &rpcError{
-		code: c,
-		desc: fmt.Sprintf(format, a...),
-	}
+	return status.Errorf(c, format, a...)
 }
 
-// toRPCErr converts an error into a rpcError.
+// toRPCErr converts an error into an error from the status package.
 func toRPCErr(err error) error {
-	switch e := err.(type) {
-	case *rpcError:
+	if _, ok := status.FromError(err); ok {
 		return err
+	}
+	switch e := err.(type) {
 	case transport.StreamError:
-		return &rpcError{
-			code: e.Code,
-			desc: e.Desc,
-		}
+		return status.Error(e.Code, e.Desc)
 	case transport.ConnectionError:
-		return &rpcError{
-			code: codes.Internal,
-			desc: e.Desc,
-		}
+		return status.Error(codes.Internal, e.Desc)
 	default:
 		switch err {
 		case context.DeadlineExceeded:
-			return &rpcError{
-				code: codes.DeadlineExceeded,
-				desc: err.Error(),
-			}
+			return status.Error(codes.DeadlineExceeded, err.Error())
 		case context.Canceled:
-			return &rpcError{
-				code: codes.Canceled,
-				desc: err.Error(),
-			}
+			return status.Error(codes.Canceled, err.Error())
 		case ErrClientConnClosing:
-			return &rpcError{
-				code: codes.FailedPrecondition,
-				desc: err.Error(),
-			}
+			return status.Error(codes.FailedPrecondition, err.Error())
 		}
-
 	}
-	return Errorf(codes.Unknown, "%v", err)
+	return status.Error(codes.Unknown, err.Error())
 }
 
 // convertCode converts a standard Go error into its canonical code. Note that
@@ -448,10 +426,51 @@ func convertCode(err error) codes.Code {
 	return codes.Unknown
 }
 
-// SupportPackageIsVersion3 is referenced from generated protocol buffer files
+// MethodConfig defines the configuration recommended by the service providers for a
+// particular method.
+// This is EXPERIMENTAL and subject to change.
+type MethodConfig struct {
+	// WaitForReady indicates whether RPCs sent to this method should wait until
+	// the connection is ready by default (!failfast). The value specified via the
+	// gRPC client API will override the value set here.
+	WaitForReady bool
+	// Timeout is the default timeout for RPCs sent to this method. The actual
+	// deadline used will be the minimum of the value specified here and the value
+	// set by the application via the gRPC client API.  If either one is not set,
+	// then the other will be used.  If neither is set, then the RPC has no deadline.
+	Timeout time.Duration
+	// MaxReqSize is the maximum allowed payload size for an individual request in a
+	// stream (client->server) in bytes. The size which is measured is the serialized
+	// payload after per-message compression (but before stream compression) in bytes.
+	// The actual value used is the minumum of the value specified here and the value set
+	// by the application via the gRPC client API. If either one is not set, then the other
+	// will be used.  If neither is set, then the built-in default is used.
+	// TODO: support this.
+	MaxReqSize uint32
+	// MaxRespSize is the maximum allowed payload size for an individual response in a
+	// stream (server->client) in bytes.
+	// TODO: support this.
+	MaxRespSize uint32
+}
+
+// ServiceConfig is provided by the service provider and contains parameters for how
+// clients that connect to the service should behave.
+// This is EXPERIMENTAL and subject to change.
+type ServiceConfig struct {
+	// LB is the load balancer the service providers recommends. The balancer specified
+	// via grpc.WithBalancer will override this.
+	LB Balancer
+	// Methods contains a map for the methods in this service.
+	Methods map[string]MethodConfig
+}
+
+// SupportPackageIsVersion4 is referenced from generated protocol buffer files
 // to assert that that code is compatible with this version of the grpc package.
 //
 // This constant may be renamed in the future if a change in the generated code
 // requires a synchronised update of grpc-go and protoc-gen-go. This constant
 // should not be referenced from any other code.
-const SupportPackageIsVersion3 = true
+const SupportPackageIsVersion4 = true
+
+// Version is the current grpc version.
+const Version = "1.3.0-dev"

vendor/google.golang.org/grpc/server.go

@@ -53,7 +53,11 @@ import (
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/grpclog"
 	"google.golang.org/grpc/internal"
+	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
+	"google.golang.org/grpc/tap"
 	"google.golang.org/grpc/transport"
 )
 
@@ -89,10 +93,12 @@ type service struct {
 type Server struct {
 	opts options
 
-	mu    sync.Mutex // guards following
-	lis   map[net.Listener]bool
-	conns map[io.Closer]bool
-	drain bool
+	mu     sync.Mutex // guards following
+	lis    map[net.Listener]bool
+	conns  map[io.Closer]bool
+	drain  bool
+	ctx    context.Context
+	cancel context.CancelFunc
 	// A CondVar to let GracefulStop() blocks until all the pending RPCs are finished
 	// and all the transport goes away.
 	cv     *sync.Cond
@@ -108,8 +114,13 @@ type options struct {
 	maxMsgSize           int
 	unaryInt             UnaryServerInterceptor
 	streamInt            StreamServerInterceptor
+	inTapHandle          tap.ServerInHandle
+	statsHandler         stats.Handler
 	maxConcurrentStreams uint32
 	useHandlerImpl       bool // use http.Handler-based server
+	unknownStreamDesc    *StreamDesc
+	keepaliveParams      keepalive.ServerParameters
+	keepalivePolicy      keepalive.EnforcementPolicy
 }
 
 var defaultMaxMsgSize = 1024 * 1024 * 4 // use 4MB as the default message size limit
@@ -117,6 +128,20 @@ var defaultMaxMsgSize = 1024 * 1024 * 4 // use 4MB as the default message size l
 // A ServerOption sets options.
 type ServerOption func(*options)
 
+// KeepaliveParams returns a ServerOption that sets keepalive and max-age parameters for the server.
+func KeepaliveParams(kp keepalive.ServerParameters) ServerOption {
+	return func(o *options) {
+		o.keepaliveParams = kp
+	}
+}
+
+// KeepaliveEnforcementPolicy returns a ServerOption that sets keepalive enforcement policy for the server.
+func KeepaliveEnforcementPolicy(kep keepalive.EnforcementPolicy) ServerOption {
+	return func(o *options) {
+		o.keepalivePolicy = kep
+	}
+}
+
 // CustomCodec returns a ServerOption that sets a codec for message marshaling and unmarshaling.
 func CustomCodec(codec Codec) ServerOption {
 	return func(o *options) {
@@ -184,6 +209,42 @@ func StreamInterceptor(i StreamServerInterceptor) ServerOption {
 	}
 }
 
+// InTapHandle returns a ServerOption that sets the tap handle for all the server
+// transport to be created. Only one can be installed.
+func InTapHandle(h tap.ServerInHandle) ServerOption {
+	return func(o *options) {
+		if o.inTapHandle != nil {
+			panic("The tap handle has been set.")
+		}
+		o.inTapHandle = h
+	}
+}
+
+// StatsHandler returns a ServerOption that sets the stats handler for the server.
+func StatsHandler(h stats.Handler) ServerOption {
+	return func(o *options) {
+		o.statsHandler = h
+	}
+}
+
+// UnknownServiceHandler returns a ServerOption that allows for adding a custom
+// unknown service handler. The provided method is a bidi-streaming RPC service
+// handler that will be invoked instead of returning the the "unimplemented" gRPC
+// error whenever a request is received for an unregistered service or method.
+// The handling function has full access to the Context of the request and the
+// stream, and the invocation passes through interceptors.
+func UnknownServiceHandler(streamHandler StreamHandler) ServerOption {
+	return func(o *options) {
+		o.unknownStreamDesc = &StreamDesc{
+			StreamName: "unknown_service_handler",
+			Handler:    streamHandler,
+			// We need to assume that the users of the streamHandler will want to use both.
+			ClientStreams: true,
+			ServerStreams: true,
+		}
+	}
+}
+
 // NewServer creates a gRPC server which has no service registered and has not
 // started to accept requests yet.
 func NewServer(opt ...ServerOption) *Server {
@@ -203,6 +264,7 @@ func NewServer(opt ...ServerOption) *Server {
 		m:     make(map[string]*service),
 	}
 	s.cv = sync.NewCond(&s.mu)
+	s.ctx, s.cancel = context.WithCancel(context.Background())
 	if EnableTracing {
 		_, file, line, _ := runtime.Caller(1)
 		s.events = trace.NewEventLog("grpc.Server", fmt.Sprintf("%s:%d", file, line))
@@ -324,8 +386,9 @@ func (s *Server) useTransportAuthenticator(rawConn net.Conn) (net.Conn, credenti
 // Serve accepts incoming connections on the listener lis, creating a new
 // ServerTransport and service goroutine for each. The service goroutines
 // read gRPC requests and then call the registered handlers to reply to them.
-// Serve returns when lis.Accept fails. lis will be closed when
+// Serve returns when lis.Accept fails with fatal errors.  lis will be closed when
 // this method returns.
+// Serve always returns non-nil error.
 func (s *Server) Serve(lis net.Listener) error {
 	s.mu.Lock()
 	s.printf("serving")
@@ -344,14 +407,38 @@ func (s *Server) Serve(lis net.Listener) error {
 		}
 		s.mu.Unlock()
 	}()
+
+	var tempDelay time.Duration // how long to sleep on accept failure
+
 	for {
 		rawConn, err := lis.Accept()
 		if err != nil {
+			if ne, ok := err.(interface {
+				Temporary() bool
+			}); ok && ne.Temporary() {
+				if tempDelay == 0 {
+					tempDelay = 5 * time.Millisecond
+				} else {
+					tempDelay *= 2
+				}
+				if max := 1 * time.Second; tempDelay > max {
+					tempDelay = max
+				}
+				s.mu.Lock()
+				s.printf("Accept error: %v; retrying in %v", err, tempDelay)
+				s.mu.Unlock()
+				select {
+				case <-time.After(tempDelay):
+				case <-s.ctx.Done():
+				}
+				continue
+			}
 			s.mu.Lock()
 			s.printf("done serving; Accept = %v", err)
 			s.mu.Unlock()
 			return err
 		}
+		tempDelay = 0
 		// Start a new goroutine to deal with rawConn
 		// so we don't stall this Accept loop goroutine.
 		go s.handleRawConn(rawConn)
@@ -385,17 +472,25 @@ func (s *Server) handleRawConn(rawConn net.Conn) {
 	if s.opts.useHandlerImpl {
 		s.serveUsingHandler(conn)
 	} else {
-		s.serveNewHTTP2Transport(conn, authInfo)
+		s.serveHTTP2Transport(conn, authInfo)
 	}
 }
 
-// serveNewHTTP2Transport sets up a new http/2 transport (using the
+// serveHTTP2Transport sets up a http/2 transport (using the
 // gRPC http2 server transport in transport/http2_server.go) and
 // serves streams on it.
 // This is run in its own goroutine (it does network I/O in
 // transport.NewServerTransport).
-func (s *Server) serveNewHTTP2Transport(c net.Conn, authInfo credentials.AuthInfo) {
-	st, err := transport.NewServerTransport("http2", c, s.opts.maxConcurrentStreams, authInfo)
+func (s *Server) serveHTTP2Transport(c net.Conn, authInfo credentials.AuthInfo) {
+	config := &transport.ServerConfig{
+		MaxStreams:      s.opts.maxConcurrentStreams,
+		AuthInfo:        authInfo,
+		InTapHandle:     s.opts.inTapHandle,
+		StatsHandler:    s.opts.statsHandler,
+		KeepaliveParams: s.opts.keepaliveParams,
+		KeepalivePolicy: s.opts.keepalivePolicy,
+	}
+	st, err := transport.NewServerTransport("http2", c, config)
 	if err != nil {
 		s.mu.Lock()
 		s.errorf("NewServerTransport(%q) failed: %v", c.RemoteAddr(), err)
@@ -421,6 +516,12 @@ func (s *Server) serveStreams(st transport.ServerTransport) {
 			defer wg.Done()
 			s.handleStream(st, stream, s.traceInfo(st, stream))
 		}()
+	}, func(ctx context.Context, method string) context.Context {
+		if !EnableTracing {
+			return ctx
+		}
+		tr := trace.New("grpc.Recv."+methodFamily(method), method)
+		return trace.NewContext(ctx, tr)
 	})
 	wg.Wait()
 }
@@ -470,15 +571,17 @@ func (s *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 // traceInfo returns a traceInfo and associates it with stream, if tracing is enabled.
 // If tracing is not enabled, it returns nil.
 func (s *Server) traceInfo(st transport.ServerTransport, stream *transport.Stream) (trInfo *traceInfo) {
-	if !EnableTracing {
+	tr, ok := trace.FromContext(stream.Context())
+	if !ok {
 		return nil
 	}
+
 	trInfo = &traceInfo{
-		tr: trace.New("grpc.Recv."+methodFamily(stream.Method()), stream.Method()),
+		tr: tr,
 	}
 	trInfo.firstLine.client = false
 	trInfo.firstLine.remoteAddr = st.RemoteAddr()
-	stream.TraceContext(trInfo.tr)
+
 	if dl, ok := stream.Context().Deadline(); ok {
 		trInfo.firstLine.deadline = dl.Sub(time.Now())
 	}
@@ -500,16 +603,22 @@ func (s *Server) removeConn(c io.Closer) {
 	defer s.mu.Unlock()
 	if s.conns != nil {
 		delete(s.conns, c)
-		s.cv.Signal()
+		s.cv.Broadcast()
 	}
 }
 
 func (s *Server) sendResponse(t transport.ServerTransport, stream *transport.Stream, msg interface{}, cp Compressor, opts *transport.Options) error {
-	var cbuf *bytes.Buffer
+	var (
+		cbuf       *bytes.Buffer
+		outPayload *stats.OutPayload
+	)
 	if cp != nil {
 		cbuf = new(bytes.Buffer)
 	}
-	p, err := encode(s.opts.codec, msg, cp, cbuf)
+	if s.opts.statsHandler != nil {
+		outPayload = &stats.OutPayload{}
+	}
+	p, err := encode(s.opts.codec, msg, cp, cbuf, outPayload)
 	if err != nil {
 		// This typically indicates a fatal issue (e.g., memory
 		// corruption or hardware faults) the application program
@@ -520,10 +629,33 @@ func (s *Server) sendResponse(t transport.ServerTransport, stream *transport.Str
 		// the optimal option.
 		grpclog.Fatalf("grpc: Server failed to encode response %v", err)
 	}
-	return t.Write(stream, p, opts)
+	err = t.Write(stream, p, opts)
+	if err == nil && outPayload != nil {
+		outPayload.SentTime = time.Now()
+		s.opts.statsHandler.HandleRPC(stream.Context(), outPayload)
+	}
+	return err
 }
 
 func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.Stream, srv *service, md *MethodDesc, trInfo *traceInfo) (err error) {
+	sh := s.opts.statsHandler
+	if sh != nil {
+		begin := &stats.Begin{
+			BeginTime: time.Now(),
+		}
+		sh.HandleRPC(stream.Context(), begin)
+	}
+	defer func() {
+		if sh != nil {
+			end := &stats.End{
+				EndTime: time.Now(),
+			}
+			if err != nil && err != io.EOF {
+				end.Error = toRPCErr(err)
+			}
+			sh.HandleRPC(stream.Context(), end)
+		}
+	}()
 	if trInfo != nil {
 		defer trInfo.tr.Finish()
 		trInfo.firstLine.client = false
@@ -540,7 +672,7 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 		stream.SetSendCompress(s.opts.cp.Type())
 	}
 	p := &parser{r: stream}
-	for {
+	for { // TODO: delete
 		pf, req, err := p.recvMsg(s.opts.maxMsgSize)
 		if err == io.EOF {
 			// The entire stream is done (for unary RPC only).
@@ -550,58 +682,68 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 			err = Errorf(codes.Internal, io.ErrUnexpectedEOF.Error())
 		}
 		if err != nil {
-			switch err := err.(type) {
-			case *rpcError:
-				if err := t.WriteStatus(stream, err.code, err.desc); err != nil {
-					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", err)
+			if st, ok := status.FromError(err); ok {
+				if e := t.WriteStatus(stream, st); e != nil {
+					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", e)
 				}
-			case transport.ConnectionError:
-				// Nothing to do here.
-			case transport.StreamError:
-				if err := t.WriteStatus(stream, err.Code, err.Desc); err != nil {
-					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", err)
+			} else {
+				switch st := err.(type) {
+				case transport.ConnectionError:
+					// Nothing to do here.
+				case transport.StreamError:
+					if e := t.WriteStatus(stream, status.New(st.Code, st.Desc)); e != nil {
+						grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", e)
+					}
+				default:
+					panic(fmt.Sprintf("grpc: Unexpected error (%T) from recvMsg: %v", st, st))
 				}
-			default:
-				panic(fmt.Sprintf("grpc: Unexpected error (%T) from recvMsg: %v", err, err))
 			}
 			return err
 		}
 
 		if err := checkRecvPayload(pf, stream.RecvCompress(), s.opts.dc); err != nil {
-			switch err := err.(type) {
-			case *rpcError:
-				if err := t.WriteStatus(stream, err.code, err.desc); err != nil {
-					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", err)
+			if st, ok := status.FromError(err); ok {
+				if e := t.WriteStatus(stream, st); e != nil {
+					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", e)
 				}
-			default:
-				if err := t.WriteStatus(stream, codes.Internal, err.Error()); err != nil {
-					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", err)
-				}
-
+				return err
+			}
+			if e := t.WriteStatus(stream, status.New(codes.Internal, err.Error())); e != nil {
+				grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", e)
+			}
+
+			// TODO checkRecvPayload always return RPC error. Add a return here if necessary.
+		}
+		var inPayload *stats.InPayload
+		if sh != nil {
+			inPayload = &stats.InPayload{
+				RecvTime: time.Now(),
 			}
-			return err
 		}
-		statusCode := codes.OK
-		statusDesc := ""
 		df := func(v interface{}) error {
+			if inPayload != nil {
+				inPayload.WireLength = len(req)
+			}
 			if pf == compressionMade {
 				var err error
 				req, err = s.opts.dc.Do(bytes.NewReader(req))
 				if err != nil {
-					if err := t.WriteStatus(stream, codes.Internal, err.Error()); err != nil {
-						grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", err)
-					}
-					return err
+					return Errorf(codes.Internal, err.Error())
 				}
 			}
 			if len(req) > s.opts.maxMsgSize {
 				// TODO: Revisit the error code. Currently keep it consistent with
 				// java implementation.
-				statusCode = codes.Internal
-				statusDesc = fmt.Sprintf("grpc: server received a message of %d bytes exceeding %d limit", len(req), s.opts.maxMsgSize)
+				return status.Errorf(codes.Internal, "grpc: server received a message of %d bytes exceeding %d limit", len(req), s.opts.maxMsgSize)
 			}
 			if err := s.opts.codec.Unmarshal(req, v); err != nil {
-				return err
+				return status.Errorf(codes.Internal, "grpc: error unmarshalling request: %v", err)
+			}
+			if inPayload != nil {
+				inPayload.Payload = v
+				inPayload.Data = req
+				inPayload.Length = len(req)
+				sh.HandleRPC(stream.Context(), inPayload)
 			}
 			if trInfo != nil {
 				trInfo.tr.LazyLog(&payload{sent: false, msg: v}, true)
@@ -610,22 +752,20 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 		}
 		reply, appErr := md.Handler(srv.server, stream.Context(), df, s.opts.unaryInt)
 		if appErr != nil {
-			if err, ok := appErr.(*rpcError); ok {
-				statusCode = err.code
-				statusDesc = err.desc
-			} else {
-				statusCode = convertCode(appErr)
-				statusDesc = appErr.Error()
+			appStatus, ok := status.FromError(appErr)
+			if !ok {
+				// Convert appErr if it is not a grpc status error.
+				appErr = status.Error(convertCode(appErr), appErr.Error())
+				appStatus, _ = status.FromError(appErr)
 			}
-			if trInfo != nil && statusCode != codes.OK {
-				trInfo.tr.LazyLog(stringer(statusDesc), true)
+			if trInfo != nil {
+				trInfo.tr.LazyLog(stringer(appStatus.Message()), true)
 				trInfo.tr.SetError()
 			}
-			if err := t.WriteStatus(stream, statusCode, statusDesc); err != nil {
-				grpclog.Printf("grpc: Server.processUnaryRPC failed to write status: %v", err)
-				return err
+			if e := t.WriteStatus(stream, appStatus); e != nil {
+				grpclog.Printf("grpc: Server.processUnaryRPC failed to write status: %v", e)
 			}
-			return nil
+			return appErr
 		}
 		if trInfo != nil {
 			trInfo.tr.LazyLog(stringer("OK"), false)
@@ -635,38 +775,70 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 			Delay: false,
 		}
 		if err := s.sendResponse(t, stream, reply, s.opts.cp, opts); err != nil {
-			switch err := err.(type) {
-			case transport.ConnectionError:
-				// Nothing to do here.
-			case transport.StreamError:
-				statusCode = err.Code
-				statusDesc = err.Desc
-			default:
-				statusCode = codes.Unknown
-				statusDesc = err.Error()
+			if err == io.EOF {
+				// The entire stream is done (for unary RPC only).
+				return err
+			}
+			if s, ok := status.FromError(err); ok {
+				if e := t.WriteStatus(stream, s); e != nil {
+					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status: %v", e)
+				}
+			} else {
+				switch st := err.(type) {
+				case transport.ConnectionError:
+					// Nothing to do here.
+				case transport.StreamError:
+					if e := t.WriteStatus(stream, status.New(st.Code, st.Desc)); e != nil {
+						grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", e)
+					}
+				default:
+					panic(fmt.Sprintf("grpc: Unexpected error (%T) from sendResponse: %v", st, st))
+				}
 			}
 			return err
 		}
 		if trInfo != nil {
 			trInfo.tr.LazyLog(&payload{sent: true, msg: reply}, true)
 		}
-		return t.WriteStatus(stream, statusCode, statusDesc)
+		// TODO: Should we be logging if writing status failed here, like above?
+		// Should the logging be in WriteStatus?  Should we ignore the WriteStatus
+		// error or allow the stats handler to see it?
+		return t.WriteStatus(stream, status.New(codes.OK, ""))
 	}
 }
 
 func (s *Server) processStreamingRPC(t transport.ServerTransport, stream *transport.Stream, srv *service, sd *StreamDesc, trInfo *traceInfo) (err error) {
+	sh := s.opts.statsHandler
+	if sh != nil {
+		begin := &stats.Begin{
+			BeginTime: time.Now(),
+		}
+		sh.HandleRPC(stream.Context(), begin)
+	}
+	defer func() {
+		if sh != nil {
+			end := &stats.End{
+				EndTime: time.Now(),
+			}
+			if err != nil && err != io.EOF {
+				end.Error = toRPCErr(err)
+			}
+			sh.HandleRPC(stream.Context(), end)
+		}
+	}()
 	if s.opts.cp != nil {
 		stream.SetSendCompress(s.opts.cp.Type())
 	}
 	ss := &serverStream{
-		t:          t,
-		s:          stream,
-		p:          &parser{r: stream},
-		codec:      s.opts.codec,
-		cp:         s.opts.cp,
-		dc:         s.opts.dc,
-		maxMsgSize: s.opts.maxMsgSize,
-		trInfo:     trInfo,
+		t:            t,
+		s:            stream,
+		p:            &parser{r: stream},
+		codec:        s.opts.codec,
+		cp:           s.opts.cp,
+		dc:           s.opts.dc,
+		maxMsgSize:   s.opts.maxMsgSize,
+		trInfo:       trInfo,
+		statsHandler: sh,
 	}
 	if ss.cp != nil {
 		ss.cbuf = new(bytes.Buffer)
@@ -685,39 +857,47 @@ func (s *Server) processStreamingRPC(t transport.ServerTransport, stream *transp
 		}()
 	}
 	var appErr error
+	var server interface{}
+	if srv != nil {
+		server = srv.server
+	}
 	if s.opts.streamInt == nil {
-		appErr = sd.Handler(srv.server, ss)
+		appErr = sd.Handler(server, ss)
 	} else {
 		info := &StreamServerInfo{
 			FullMethod:     stream.Method(),
 			IsClientStream: sd.ClientStreams,
 			IsServerStream: sd.ServerStreams,
 		}
-		appErr = s.opts.streamInt(srv.server, ss, info, sd.Handler)
+		appErr = s.opts.streamInt(server, ss, info, sd.Handler)
 	}
 	if appErr != nil {
-		if err, ok := appErr.(*rpcError); ok {
-			ss.statusCode = err.code
-			ss.statusDesc = err.desc
-		} else if err, ok := appErr.(transport.StreamError); ok {
-			ss.statusCode = err.Code
-			ss.statusDesc = err.Desc
-		} else {
-			ss.statusCode = convertCode(appErr)
-			ss.statusDesc = appErr.Error()
+		appStatus, ok := status.FromError(appErr)
+		if !ok {
+			switch err := appErr.(type) {
+			case transport.StreamError:
+				appStatus = status.New(err.Code, err.Desc)
+			default:
+				appStatus = status.New(convertCode(appErr), appErr.Error())
+			}
+			appErr = appStatus.Err()
 		}
+		if trInfo != nil {
+			ss.mu.Lock()
+			ss.trInfo.tr.LazyLog(stringer(appStatus.Message()), true)
+			ss.trInfo.tr.SetError()
+			ss.mu.Unlock()
+		}
+		t.WriteStatus(ss.s, appStatus)
+		// TODO: Should we log an error from WriteStatus here and below?
+		return appErr
 	}
 	if trInfo != nil {
 		ss.mu.Lock()
-		if ss.statusCode != codes.OK {
-			ss.trInfo.tr.LazyLog(stringer(ss.statusDesc), true)
-			ss.trInfo.tr.SetError()
-		} else {
-			ss.trInfo.tr.LazyLog(stringer("OK"), false)
-		}
+		ss.trInfo.tr.LazyLog(stringer("OK"), false)
 		ss.mu.Unlock()
 	}
-	return t.WriteStatus(ss.s, ss.statusCode, ss.statusDesc)
+	return t.WriteStatus(ss.s, status.New(codes.OK, ""))
 
 }
 
@@ -732,7 +912,8 @@ func (s *Server) handleStream(t transport.ServerTransport, stream *transport.Str
 			trInfo.tr.LazyLog(&fmtStringer{"Malformed method name %q", []interface{}{sm}}, true)
 			trInfo.tr.SetError()
 		}
-		if err := t.WriteStatus(stream, codes.InvalidArgument, fmt.Sprintf("malformed method name: %q", stream.Method())); err != nil {
+		errDesc := fmt.Sprintf("malformed method name: %q", stream.Method())
+		if err := t.WriteStatus(stream, status.New(codes.InvalidArgument, errDesc)); err != nil {
 			if trInfo != nil {
 				trInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true)
 				trInfo.tr.SetError()
@@ -748,11 +929,16 @@ func (s *Server) handleStream(t transport.ServerTransport, stream *transport.Str
 	method := sm[pos+1:]
 	srv, ok := s.m[service]
 	if !ok {
+		if unknownDesc := s.opts.unknownStreamDesc; unknownDesc != nil {
+			s.processStreamingRPC(t, stream, nil, unknownDesc, trInfo)
+			return
+		}
 		if trInfo != nil {
 			trInfo.tr.LazyLog(&fmtStringer{"Unknown service %v", []interface{}{service}}, true)
 			trInfo.tr.SetError()
 		}
-		if err := t.WriteStatus(stream, codes.Unimplemented, fmt.Sprintf("unknown service %v", service)); err != nil {
+		errDesc := fmt.Sprintf("unknown service %v", service)
+		if err := t.WriteStatus(stream, status.New(codes.Unimplemented, errDesc)); err != nil {
 			if trInfo != nil {
 				trInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true)
 				trInfo.tr.SetError()
@@ -777,7 +963,12 @@ func (s *Server) handleStream(t transport.ServerTransport, stream *transport.Str
 		trInfo.tr.LazyLog(&fmtStringer{"Unknown method %v", []interface{}{method}}, true)
 		trInfo.tr.SetError()
 	}
-	if err := t.WriteStatus(stream, codes.Unimplemented, fmt.Sprintf("unknown method %v", method)); err != nil {
+	if unknownDesc := s.opts.unknownStreamDesc; unknownDesc != nil {
+		s.processStreamingRPC(t, stream, nil, unknownDesc, trInfo)
+		return
+	}
+	errDesc := fmt.Sprintf("unknown method %v", method)
+	if err := t.WriteStatus(stream, status.New(codes.Unimplemented, errDesc)); err != nil {
 		if trInfo != nil {
 			trInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true)
 			trInfo.tr.SetError()
@@ -801,7 +992,7 @@ func (s *Server) Stop() {
 	st := s.conns
 	s.conns = nil
 	// interrupt GracefulStop if Stop and GracefulStop are called concurrently.
-	s.cv.Signal()
+	s.cv.Broadcast()
 	s.mu.Unlock()
 
 	for lis := range listeners {
@@ -812,6 +1003,7 @@ func (s *Server) Stop() {
 	}
 
 	s.mu.Lock()
+	s.cancel()
 	if s.events != nil {
 		s.events.Finish()
 		s.events = nil
@@ -824,16 +1016,19 @@ func (s *Server) Stop() {
 func (s *Server) GracefulStop() {
 	s.mu.Lock()
 	defer s.mu.Unlock()
-	if s.drain == true || s.conns == nil {
+	if s.conns == nil {
 		return
 	}
-	s.drain = true
 	for lis := range s.lis {
 		lis.Close()
 	}
 	s.lis = nil
-	for c := range s.conns {
-		c.(transport.ServerTransport).Drain()
+	s.cancel()
+	if !s.drain {
+		for c := range s.conns {
+			c.(transport.ServerTransport).Drain()
+		}
+		s.drain = true
 	}
 	for len(s.conns) != 0 {
 		s.cv.Wait()
@@ -865,12 +1060,26 @@ func (s *Server) testingCloseConns() {
 	s.mu.Unlock()
 }
 
-// SendHeader sends header metadata. It may be called at most once from a unary
-// RPC handler. The ctx is the RPC handler's Context or one derived from it.
-func SendHeader(ctx context.Context, md metadata.MD) error {
+// SetHeader sets the header metadata.
+// When called multiple times, all the provided metadata will be merged.
+// All the metadata will be sent out when one of the following happens:
+//  - grpc.SendHeader() is called;
+//  - The first response is sent out;
+//  - An RPC status is sent out (error or success).
+func SetHeader(ctx context.Context, md metadata.MD) error {
 	if md.Len() == 0 {
 		return nil
 	}
+	stream, ok := transport.StreamFromContext(ctx)
+	if !ok {
+		return Errorf(codes.Internal, "grpc: failed to fetch the stream from the context %v", ctx)
+	}
+	return stream.SetHeader(md)
+}
+
+// SendHeader sends header metadata. It may be called at most once.
+// The provided md and headers set by SetHeader() will be sent.
+func SendHeader(ctx context.Context, md metadata.MD) error {
 	stream, ok := transport.StreamFromContext(ctx)
 	if !ok {
 		return Errorf(codes.Internal, "grpc: failed to fetch the stream from the context %v", ctx)
@@ -887,7 +1096,6 @@ func SendHeader(ctx context.Context, md metadata.MD) error {
 
 // SetTrailer sets the trailer metadata that will be sent when an RPC returns.
 // When called more than once, all the provided metadata will be merged.
-// The ctx is the RPC handler's Context or one derived from it.
 func SetTrailer(ctx context.Context, md metadata.MD) error {
 	if md.Len() == 0 {
 		return nil

vendor/google.golang.org/grpc/stats/handlers.go

@@ -0,0 +1,76 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+package stats
+
+import (
+	"net"
+
+	"golang.org/x/net/context"
+)
+
+// ConnTagInfo defines the relevant information needed by connection context tagger.
+type ConnTagInfo struct {
+	// RemoteAddr is the remote address of the corresponding connection.
+	RemoteAddr net.Addr
+	// LocalAddr is the local address of the corresponding connection.
+	LocalAddr net.Addr
+	// TODO add QOS related fields.
+}
+
+// RPCTagInfo defines the relevant information needed by RPC context tagger.
+type RPCTagInfo struct {
+	// FullMethodName is the RPC method in the format of /package.service/method.
+	FullMethodName string
+}
+
+// Handler defines the interface for the related stats handling (e.g., RPCs, connections).
+type Handler interface {
+	// TagRPC can attach some information to the given context.
+	// The returned context is used in the rest lifetime of the RPC.
+	TagRPC(context.Context, *RPCTagInfo) context.Context
+	// HandleRPC processes the RPC stats.
+	HandleRPC(context.Context, RPCStats)
+
+	// TagConn can attach some information to the given context.
+	// The returned context will be used for stats handling.
+	// For conn stats handling, the context used in HandleConn for this
+	// connection will be derived from the context returned.
+	// For RPC stats handling,
+	//  - On server side, the context used in HandleRPC for all RPCs on this
+	// connection will be derived from the context returned.
+	//  - On client side, the context is not derived from the context returned.
+	TagConn(context.Context, *ConnTagInfo) context.Context
+	// HandleConn processes the Conn stats.
+	HandleConn(context.Context, ConnStats)
+}

vendor/google.golang.org/grpc/stats/stats.go

@@ -0,0 +1,223 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+// Package stats is for collecting and reporting various network and RPC stats.
+// This package is for monitoring purpose only. All fields are read-only.
+// All APIs are experimental.
+package stats // import "google.golang.org/grpc/stats"
+
+import (
+	"net"
+	"time"
+)
+
+// RPCStats contains stats information about RPCs.
+type RPCStats interface {
+	isRPCStats()
+	// IsClient returns true if this RPCStats is from client side.
+	IsClient() bool
+}
+
+// Begin contains stats when an RPC begins.
+// FailFast are only valid if Client is true.
+type Begin struct {
+	// Client is true if this Begin is from client side.
+	Client bool
+	// BeginTime is the time when the RPC begins.
+	BeginTime time.Time
+	// FailFast indicates if this RPC is failfast.
+	FailFast bool
+}
+
+// IsClient indicates if this is from client side.
+func (s *Begin) IsClient() bool { return s.Client }
+
+func (s *Begin) isRPCStats() {}
+
+// InPayload contains the information for an incoming payload.
+type InPayload struct {
+	// Client is true if this InPayload is from client side.
+	Client bool
+	// Payload is the payload with original type.
+	Payload interface{}
+	// Data is the serialized message payload.
+	Data []byte
+	// Length is the length of uncompressed data.
+	Length int
+	// WireLength is the length of data on wire (compressed, signed, encrypted).
+	WireLength int
+	// RecvTime is the time when the payload is received.
+	RecvTime time.Time
+}
+
+// IsClient indicates if this is from client side.
+func (s *InPayload) IsClient() bool { return s.Client }
+
+func (s *InPayload) isRPCStats() {}
+
+// InHeader contains stats when a header is received.
+// FullMethod, addresses and Compression are only valid if Client is false.
+type InHeader struct {
+	// Client is true if this InHeader is from client side.
+	Client bool
+	// WireLength is the wire length of header.
+	WireLength int
+
+	// FullMethod is the full RPC method string, i.e., /package.service/method.
+	FullMethod string
+	// RemoteAddr is the remote address of the corresponding connection.
+	RemoteAddr net.Addr
+	// LocalAddr is the local address of the corresponding connection.
+	LocalAddr net.Addr
+	// Compression is the compression algorithm used for the RPC.
+	Compression string
+}
+
+// IsClient indicates if this is from client side.
+func (s *InHeader) IsClient() bool { return s.Client }
+
+func (s *InHeader) isRPCStats() {}
+
+// InTrailer contains stats when a trailer is received.
+type InTrailer struct {
+	// Client is true if this InTrailer is from client side.
+	Client bool
+	// WireLength is the wire length of trailer.
+	WireLength int
+}
+
+// IsClient indicates if this is from client side.
+func (s *InTrailer) IsClient() bool { return s.Client }
+
+func (s *InTrailer) isRPCStats() {}
+
+// OutPayload contains the information for an outgoing payload.
+type OutPayload struct {
+	// Client is true if this OutPayload is from client side.
+	Client bool
+	// Payload is the payload with original type.
+	Payload interface{}
+	// Data is the serialized message payload.
+	Data []byte
+	// Length is the length of uncompressed data.
+	Length int
+	// WireLength is the length of data on wire (compressed, signed, encrypted).
+	WireLength int
+	// SentTime is the time when the payload is sent.
+	SentTime time.Time
+}
+
+// IsClient indicates if this is from client side.
+func (s *OutPayload) IsClient() bool { return s.Client }
+
+func (s *OutPayload) isRPCStats() {}
+
+// OutHeader contains stats when a header is sent.
+// FullMethod, addresses and Compression are only valid if Client is true.
+type OutHeader struct {
+	// Client is true if this OutHeader is from client side.
+	Client bool
+	// WireLength is the wire length of header.
+	WireLength int
+
+	// FullMethod is the full RPC method string, i.e., /package.service/method.
+	FullMethod string
+	// RemoteAddr is the remote address of the corresponding connection.
+	RemoteAddr net.Addr
+	// LocalAddr is the local address of the corresponding connection.
+	LocalAddr net.Addr
+	// Compression is the compression algorithm used for the RPC.
+	Compression string
+}
+
+// IsClient indicates if this is from client side.
+func (s *OutHeader) IsClient() bool { return s.Client }
+
+func (s *OutHeader) isRPCStats() {}
+
+// OutTrailer contains stats when a trailer is sent.
+type OutTrailer struct {
+	// Client is true if this OutTrailer is from client side.
+	Client bool
+	// WireLength is the wire length of trailer.
+	WireLength int
+}
+
+// IsClient indicates if this is from client side.
+func (s *OutTrailer) IsClient() bool { return s.Client }
+
+func (s *OutTrailer) isRPCStats() {}
+
+// End contains stats when an RPC ends.
+type End struct {
+	// Client is true if this End is from client side.
+	Client bool
+	// EndTime is the time when the RPC ends.
+	EndTime time.Time
+	// Error is the error just happened.  It implements status.Status if non-nil.
+	Error error
+}
+
+// IsClient indicates if this is from client side.
+func (s *End) IsClient() bool { return s.Client }
+
+func (s *End) isRPCStats() {}
+
+// ConnStats contains stats information about connections.
+type ConnStats interface {
+	isConnStats()
+	// IsClient returns true if this ConnStats is from client side.
+	IsClient() bool
+}
+
+// ConnBegin contains the stats of a connection when it is established.
+type ConnBegin struct {
+	// Client is true if this ConnBegin is from client side.
+	Client bool
+}
+
+// IsClient indicates if this is from client side.
+func (s *ConnBegin) IsClient() bool { return s.Client }
+
+func (s *ConnBegin) isConnStats() {}
+
+// ConnEnd contains the stats of a connection when it ends.
+type ConnEnd struct {
+	// Client is true if this ConnEnd is from client side.
+	Client bool
+}
+
+// IsClient indicates if this is from client side.
+func (s *ConnEnd) IsClient() bool { return s.Client }
+
+func (s *ConnEnd) isConnStats() {}

vendor/google.golang.org/grpc/status/status.go

@@ -0,0 +1,136 @@
+/*
+ *
+ * Copyright 2017, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+// Package status implements errors returned by gRPC.  These errors are
+// serialized and transmitted on the wire between server and client, and allow
+// for additional data to be transmitted via the Details field in the status
+// proto.  gRPC service handlers should return an error created by this
+// package, and gRPC clients should expect a corresponding error to be
+// returned from the RPC call.
+//
+// This package upholds the invariants that a non-nil error may not
+// contain an OK code, and an OK code must result in a nil error.
+package status
+
+import (
+	"fmt"
+
+	"github.com/golang/protobuf/proto"
+	spb "google.golang.org/genproto/googleapis/rpc/status"
+	"google.golang.org/grpc/codes"
+)
+
+// statusError is an alias of a status proto.  It implements error and Status,
+// and a nil statusError should never be returned by this package.
+type statusError spb.Status
+
+func (se *statusError) Error() string {
+	p := (*spb.Status)(se)
+	return fmt.Sprintf("rpc error: code = %s desc = %s", codes.Code(p.GetCode()), p.GetMessage())
+}
+
+func (se *statusError) status() *Status {
+	return &Status{s: (*spb.Status)(se)}
+}
+
+// Status represents an RPC status code, message, and details.  It is immutable
+// and should be created with New, Newf, or FromProto.
+type Status struct {
+	s *spb.Status
+}
+
+// Code returns the status code contained in s.
+func (s *Status) Code() codes.Code {
+	return codes.Code(s.s.Code)
+}
+
+// Message returns the message contained in s.
+func (s *Status) Message() string {
+	return s.s.Message
+}
+
+// Proto returns s's status as an spb.Status proto message.
+func (s *Status) Proto() *spb.Status {
+	return proto.Clone(s.s).(*spb.Status)
+}
+
+// Err returns an immutable error representing s; returns nil if s.Code() is
+// OK.
+func (s *Status) Err() error {
+	if s.Code() == codes.OK {
+		return nil
+	}
+	return (*statusError)(s.s)
+}
+
+// New returns a Status representing c and msg.
+func New(c codes.Code, msg string) *Status {
+	return &Status{s: &spb.Status{Code: int32(c), Message: msg}}
+}
+
+// Newf returns New(c, fmt.Sprintf(format, a...)).
+func Newf(c codes.Code, format string, a ...interface{}) *Status {
+	return New(c, fmt.Sprintf(format, a...))
+}
+
+// Error returns an error representing c and msg.  If c is OK, returns nil.
+func Error(c codes.Code, msg string) error {
+	return New(c, msg).Err()
+}
+
+// Errorf returns Error(c, fmt.Sprintf(format, a...)).
+func Errorf(c codes.Code, format string, a ...interface{}) error {
+	return Error(c, fmt.Sprintf(format, a...))
+}
+
+// ErrorProto returns an error representing s.  If s.Code is OK, returns nil.
+func ErrorProto(s *spb.Status) error {
+	return FromProto(s).Err()
+}
+
+// FromProto returns a Status representing s.
+func FromProto(s *spb.Status) *Status {
+	return &Status{s: proto.Clone(s).(*spb.Status)}
+}
+
+// FromError returns a Status representing err if it was produced from this
+// package, otherwise it returns nil, false.
+func FromError(err error) (s *Status, ok bool) {
+	if err == nil {
+		return &Status{s: &spb.Status{Code: int32(codes.OK)}}, true
+	}
+	if s, ok := err.(*statusError); ok {
+		return s.status(), true
+	}
+	return nil, false
+}

vendor/google.golang.org/grpc/stream.go

@@ -37,7 +37,6 @@ import (
 	"bytes"
 	"errors"
 	"io"
-	"math"
 	"sync"
 	"time"
 
@@ -45,6 +44,8 @@ import (
 	"golang.org/x/net/trace"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/transport"
 )
 
@@ -97,7 +98,7 @@ type ClientStream interface {
 
 // NewClientStream creates a new Stream for the client side. This is called
 // by generated code.
-func NewClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, method string, opts ...CallOption) (ClientStream, error) {
+func NewClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, method string, opts ...CallOption) (_ ClientStream, err error) {
 	if cc.dopts.streamInt != nil {
 		return cc.dopts.streamInt(ctx, desc, cc, method, newClientStream, opts...)
 	}
@@ -106,11 +107,18 @@ func NewClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 
 func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, method string, opts ...CallOption) (_ ClientStream, err error) {
 	var (
-		t   transport.ClientTransport
-		s   *transport.Stream
-		put func()
+		t      transport.ClientTransport
+		s      *transport.Stream
+		put    func()
+		cancel context.CancelFunc
 	)
 	c := defaultCallInfo
+	if mc, ok := cc.getMethodConfig(method); ok {
+		c.failFast = !mc.WaitForReady
+		if mc.Timeout > 0 {
+			ctx, cancel = context.WithTimeout(ctx, mc.Timeout)
+		}
+	}
 	for _, o := range opts {
 		if err := o.before(&c); err != nil {
 			return nil, toRPCErr(err)
@@ -143,6 +151,26 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 			}
 		}()
 	}
+	sh := cc.dopts.copts.StatsHandler
+	if sh != nil {
+		ctx = sh.TagRPC(ctx, &stats.RPCTagInfo{FullMethodName: method})
+		begin := &stats.Begin{
+			Client:    true,
+			BeginTime: time.Now(),
+			FailFast:  c.failFast,
+		}
+		sh.HandleRPC(ctx, begin)
+	}
+	defer func() {
+		if err != nil && sh != nil {
+			// Only handle end stats if err != nil.
+			end := &stats.End{
+				Client: true,
+				Error:  err,
+			}
+			sh.HandleRPC(ctx, end)
+		}
+	}()
 	gopts := BalancerGetOptions{
 		BlockingWait: !c.failFast,
 	}
@@ -150,7 +178,7 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 		t, put, err = cc.getTransport(ctx, gopts)
 		if err != nil {
 			// TODO(zhaoq): Probably revisit the error handling.
-			if _, ok := err.(*rpcError); ok {
+			if _, ok := status.FromError(err); ok {
 				return nil, err
 			}
 			if err == errConnClosing || err == errConnUnavailable {
@@ -180,12 +208,14 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 		break
 	}
 	cs := &clientStream{
-		opts:  opts,
-		c:     c,
-		desc:  desc,
-		codec: cc.dopts.codec,
-		cp:    cc.dopts.cp,
-		dc:    cc.dopts.dc,
+		opts:       opts,
+		c:          c,
+		desc:       desc,
+		codec:      cc.dopts.codec,
+		cp:         cc.dopts.cp,
+		dc:         cc.dopts.dc,
+		maxMsgSize: cc.dopts.maxMsgSize,
+		cancel:     cancel,
 
 		put: put,
 		t:   t,
@@ -194,6 +224,9 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 
 		tracing: EnableTracing,
 		trInfo:  trInfo,
+
+		statsCtx:     ctx,
+		statsHandler: cc.dopts.copts.StatsHandler,
 	}
 	if cc.dopts.cp != nil {
 		cs.cbuf = new(bytes.Buffer)
@@ -207,11 +240,7 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 		case <-s.Done():
 			// TODO: The trace of the RPC is terminated here when there is no pending
 			// I/O, which is probably not the optimal solution.
-			if s.StatusCode() == codes.OK {
-				cs.finish(nil)
-			} else {
-				cs.finish(Errorf(s.StatusCode(), "%s", s.StatusDesc()))
-			}
+			cs.finish(s.Status().Err())
 			cs.closeTransportStream(nil)
 		case <-s.GoAway():
 			cs.finish(errConnDrain)
@@ -227,25 +256,34 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 
 // clientStream implements a client side Stream.
 type clientStream struct {
-	opts  []CallOption
-	c     callInfo
-	t     transport.ClientTransport
-	s     *transport.Stream
-	p     *parser
-	desc  *StreamDesc
-	codec Codec
-	cp    Compressor
-	cbuf  *bytes.Buffer
-	dc    Decompressor
+	opts       []CallOption
+	c          callInfo
+	t          transport.ClientTransport
+	s          *transport.Stream
+	p          *parser
+	desc       *StreamDesc
+	codec      Codec
+	cp         Compressor
+	cbuf       *bytes.Buffer
+	dc         Decompressor
+	maxMsgSize int
+	cancel     context.CancelFunc
 
 	tracing bool // set to EnableTracing when the clientStream is created.
 
-	mu     sync.Mutex
-	put    func()
-	closed bool
+	mu       sync.Mutex
+	put      func()
+	closed   bool
+	finished bool
 	// trInfo.tr is set when the clientStream is created (if EnableTracing is true),
 	// and is set to nil when the clientStream's finish method is called.
 	trInfo traceInfo
+
+	// statsCtx keeps the user context for stats handling.
+	// All stats collection should use the statsCtx (instead of the stream context)
+	// so that all the generated stats for a particular RPC can be associated in the processing phase.
+	statsCtx     context.Context
+	statsHandler stats.Handler
 }
 
 func (cs *clientStream) Context() context.Context {
@@ -274,6 +312,8 @@ func (cs *clientStream) SendMsg(m interface{}) (err error) {
 		}
 		cs.mu.Unlock()
 	}
+	// TODO Investigate how to signal the stats handling party.
+	// generate error stats if err != nil && err != io.EOF?
 	defer func() {
 		if err != nil {
 			cs.finish(err)
@@ -296,7 +336,13 @@ func (cs *clientStream) SendMsg(m interface{}) (err error) {
 		}
 		err = toRPCErr(err)
 	}()
-	out, err := encode(cs.codec, m, cs.cp, cs.cbuf)
+	var outPayload *stats.OutPayload
+	if cs.statsHandler != nil {
+		outPayload = &stats.OutPayload{
+			Client: true,
+		}
+	}
+	out, err := encode(cs.codec, m, cs.cp, cs.cbuf, outPayload)
 	defer func() {
 		if cs.cbuf != nil {
 			cs.cbuf.Reset()
@@ -305,11 +351,22 @@ func (cs *clientStream) SendMsg(m interface{}) (err error) {
 	if err != nil {
 		return Errorf(codes.Internal, "grpc: %v", err)
 	}
-	return cs.t.Write(cs.s, out, &transport.Options{Last: false})
+	err = cs.t.Write(cs.s, out, &transport.Options{Last: false})
+	if err == nil && outPayload != nil {
+		outPayload.SentTime = time.Now()
+		cs.statsHandler.HandleRPC(cs.statsCtx, outPayload)
+	}
+	return err
 }
 
 func (cs *clientStream) RecvMsg(m interface{}) (err error) {
-	err = recv(cs.p, cs.codec, cs.s, cs.dc, m, math.MaxInt32)
+	var inPayload *stats.InPayload
+	if cs.statsHandler != nil {
+		inPayload = &stats.InPayload{
+			Client: true,
+		}
+	}
+	err = recv(cs.p, cs.codec, cs.s, cs.dc, m, cs.maxMsgSize, inPayload)
 	defer func() {
 		// err != nil indicates the termination of the stream.
 		if err != nil {
@@ -324,21 +381,25 @@ func (cs *clientStream) RecvMsg(m interface{}) (err error) {
 			}
 			cs.mu.Unlock()
 		}
+		if inPayload != nil {
+			cs.statsHandler.HandleRPC(cs.statsCtx, inPayload)
+		}
 		if !cs.desc.ClientStreams || cs.desc.ServerStreams {
 			return
 		}
 		// Special handling for client streaming rpc.
-		err = recv(cs.p, cs.codec, cs.s, cs.dc, m, math.MaxInt32)
+		// This recv expects EOF or errors, so we don't collect inPayload.
+		err = recv(cs.p, cs.codec, cs.s, cs.dc, m, cs.maxMsgSize, nil)
 		cs.closeTransportStream(err)
 		if err == nil {
 			return toRPCErr(errors.New("grpc: client streaming protocol violation: get <nil>, want <EOF>"))
 		}
 		if err == io.EOF {
-			if cs.s.StatusCode() == codes.OK {
-				cs.finish(err)
-				return nil
+			if se := cs.s.Status().Err(); se != nil {
+				return se
 			}
-			return Errorf(cs.s.StatusCode(), "%s", cs.s.StatusDesc())
+			cs.finish(err)
+			return nil
 		}
 		return toRPCErr(err)
 	}
@@ -346,11 +407,11 @@ func (cs *clientStream) RecvMsg(m interface{}) (err error) {
 		cs.closeTransportStream(err)
 	}
 	if err == io.EOF {
-		if cs.s.StatusCode() == codes.OK {
-			// Returns io.EOF to indicate the end of the stream.
-			return
+		if statusErr := cs.s.Status().Err(); statusErr != nil {
+			return statusErr
 		}
-		return Errorf(cs.s.StatusCode(), "%s", cs.s.StatusDesc())
+		// Returns io.EOF to indicate the end of the stream.
+		return
 	}
 	return toRPCErr(err)
 }
@@ -386,6 +447,15 @@ func (cs *clientStream) closeTransportStream(err error) {
 func (cs *clientStream) finish(err error) {
 	cs.mu.Lock()
 	defer cs.mu.Unlock()
+	if cs.finished {
+		return
+	}
+	cs.finished = true
+	defer func() {
+		if cs.cancel != nil {
+			cs.cancel()
+		}
+	}()
 	for _, o := range cs.opts {
 		o.after(&cs.c)
 	}
@@ -393,6 +463,17 @@ func (cs *clientStream) finish(err error) {
 		cs.put()
 		cs.put = nil
 	}
+	if cs.statsHandler != nil {
+		end := &stats.End{
+			Client:  true,
+			EndTime: time.Now(),
+		}
+		if err != io.EOF {
+			// end.Error is nil if the RPC finished successfully.
+			end.Error = toRPCErr(err)
+		}
+		cs.statsHandler.HandleRPC(cs.statsCtx, end)
+	}
 	if !cs.tracing {
 		return
 	}
@@ -410,9 +491,16 @@ func (cs *clientStream) finish(err error) {
 
 // ServerStream defines the interface a server stream has to satisfy.
 type ServerStream interface {
-	// SendHeader sends the header metadata. It should not be called
-	// after SendProto. It fails if called multiple times or if
-	// called after SendProto.
+	// SetHeader sets the header metadata. It may be called multiple times.
+	// When call multiple times, all the provided metadata will be merged.
+	// All the metadata will be sent out when one of the following happens:
+	//  - ServerStream.SendHeader() is called;
+	//  - The first response is sent out;
+	//  - An RPC status is sent out (error or success).
+	SetHeader(metadata.MD) error
+	// SendHeader sends the header metadata.
+	// The provided md and headers set by SetHeader() will be sent.
+	// It fails if called multiple times.
 	SendHeader(metadata.MD) error
 	// SetTrailer sets the trailer metadata which will be sent with the RPC status.
 	// When called more than once, all the provided metadata will be merged.
@@ -430,10 +518,10 @@ type serverStream struct {
 	dc         Decompressor
 	cbuf       *bytes.Buffer
 	maxMsgSize int
-	statusCode codes.Code
-	statusDesc string
 	trInfo     *traceInfo
 
+	statsHandler stats.Handler
+
 	mu sync.Mutex // protects trInfo.tr after the service handler runs.
 }
 
@@ -441,6 +529,13 @@ func (ss *serverStream) Context() context.Context {
 	return ss.s.Context()
 }
 
+func (ss *serverStream) SetHeader(md metadata.MD) error {
+	if md.Len() == 0 {
+		return nil
+	}
+	return ss.s.SetHeader(md)
+}
+
 func (ss *serverStream) SendHeader(md metadata.MD) error {
 	return ss.t.WriteHeader(ss.s, md)
 }
@@ -468,7 +563,11 @@ func (ss *serverStream) SendMsg(m interface{}) (err error) {
 			ss.mu.Unlock()
 		}
 	}()
-	out, err := encode(ss.codec, m, ss.cp, ss.cbuf)
+	var outPayload *stats.OutPayload
+	if ss.statsHandler != nil {
+		outPayload = &stats.OutPayload{}
+	}
+	out, err := encode(ss.codec, m, ss.cp, ss.cbuf, outPayload)
 	defer func() {
 		if ss.cbuf != nil {
 			ss.cbuf.Reset()
@@ -481,6 +580,10 @@ func (ss *serverStream) SendMsg(m interface{}) (err error) {
 	if err := ss.t.Write(ss.s, out, &transport.Options{Last: false}); err != nil {
 		return toRPCErr(err)
 	}
+	if outPayload != nil {
+		outPayload.SentTime = time.Now()
+		ss.statsHandler.HandleRPC(ss.s.Context(), outPayload)
+	}
 	return nil
 }
 
@@ -499,7 +602,11 @@ func (ss *serverStream) RecvMsg(m interface{}) (err error) {
 			ss.mu.Unlock()
 		}
 	}()
-	if err := recv(ss.p, ss.codec, ss.s, ss.dc, m, ss.maxMsgSize); err != nil {
+	var inPayload *stats.InPayload
+	if ss.statsHandler != nil {
+		inPayload = &stats.InPayload{}
+	}
+	if err := recv(ss.p, ss.codec, ss.s, ss.dc, m, ss.maxMsgSize, inPayload); err != nil {
 		if err == io.EOF {
 			return err
 		}
@@ -508,5 +615,8 @@ func (ss *serverStream) RecvMsg(m interface{}) (err error) {
 		}
 		return toRPCErr(err)
 	}
+	if inPayload != nil {
+		ss.statsHandler.HandleRPC(ss.s.Context(), inPayload)
+	}
 	return nil
 }

vendor/google.golang.org/grpc/tap/tap.go

@@ -0,0 +1,54 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+// Package tap defines the function handles which are executed on the transport
+// layer of gRPC-Go and related information. Everything here is EXPERIMENTAL.
+package tap
+
+import (
+	"golang.org/x/net/context"
+)
+
+// Info defines the relevant information needed by the handles.
+type Info struct {
+	// FullMethodName is the string of grpc method (in the format of
+	// /package.service/method).
+	FullMethodName string
+	// TODO: More to be added.
+}
+
+// ServerInHandle defines the function which runs when a new stream is created
+// on the server side. Note that it is executed in the per-connection I/O goroutine(s) instead
+// of per-RPC goroutine. Therefore, users should NOT have any blocking/time-consuming
+// work in this handle. Otherwise all the RPCs would slow down.
+type ServerInHandle func(ctx context.Context, info *Info) (context.Context, error)

vendor/google.golang.org/grpc/transport/control.go

@@ -35,7 +35,9 @@ package transport
 
 import (
 	"fmt"
+	"math"
 	"sync"
+	"time"
 
 	"golang.org/x/net/http2"
 )
@@ -44,8 +46,18 @@ const (
 	// The default value of flow control window size in HTTP2 spec.
 	defaultWindowSize = 65535
 	// The initial window size for flow control.
-	initialWindowSize     = defaultWindowSize      // for an RPC
-	initialConnWindowSize = defaultWindowSize * 16 // for a connection
+	initialWindowSize             = defaultWindowSize      // for an RPC
+	initialConnWindowSize         = defaultWindowSize * 16 // for a connection
+	infinity                      = time.Duration(math.MaxInt64)
+	defaultClientKeepaliveTime    = infinity
+	defaultClientKeepaliveTimeout = time.Duration(20 * time.Second)
+	defaultMaxStreamsClient       = 100
+	defaultMaxConnectionIdle      = infinity
+	defaultMaxConnectionAge       = infinity
+	defaultMaxConnectionAgeGrace  = infinity
+	defaultServerKeepaliveTime    = time.Duration(2 * time.Hour)
+	defaultServerKeepaliveTimeout = time.Duration(20 * time.Second)
+	defaultKeepalivePolicyMinTime = time.Duration(5 * time.Minute)
 )
 
 // The following defines various control items which could flow through
@@ -73,6 +85,8 @@ type resetStream struct {
 func (*resetStream) item() {}
 
 type goAway struct {
+	code      http2.ErrCode
+	debugData []byte
 }
 
 func (*goAway) item() {}
@@ -111,35 +125,9 @@ func newQuotaPool(q int) *quotaPool {
 	return qb
 }
 
-// add adds n to the available quota and tries to send it on acquire.
-func (qb *quotaPool) add(n int) {
-	qb.mu.Lock()
-	defer qb.mu.Unlock()
-	qb.quota += n
-	if qb.quota <= 0 {
-		return
-	}
-	select {
-	case qb.c <- qb.quota:
-		qb.quota = 0
-	default:
-	}
-}
-
-// cancel cancels the pending quota sent on acquire, if any.
-func (qb *quotaPool) cancel() {
-	qb.mu.Lock()
-	defer qb.mu.Unlock()
-	select {
-	case n := <-qb.c:
-		qb.quota += n
-	default:
-	}
-}
-
-// reset cancels the pending quota sent on acquired, incremented by v and sends
+// add cancels the pending quota sent on acquired, incremented by v and sends
 // it back on acquire.
-func (qb *quotaPool) reset(v int) {
+func (qb *quotaPool) add(v int) {
 	qb.mu.Lock()
 	defer qb.mu.Unlock()
 	select {
@@ -151,6 +139,10 @@ func (qb *quotaPool) reset(v int) {
 	if qb.quota <= 0 {
 		return
 	}
+	// After the pool has been created, this is the only place that sends on
+	// the channel. Since mu is held at this point and any quota that was sent
+	// on the channel has been retrieved, we know that this code will always
+	// place any positive quota value on the channel.
 	select {
 	case qb.c <- qb.quota:
 		qb.quota = 0

vendor/google.golang.org/grpc/transport/handler_server.go

@@ -53,6 +53,7 @@ import (
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
+	"google.golang.org/grpc/status"
 )
 
 // NewServerHandlerTransport returns a ServerTransport handling gRPC
@@ -182,7 +183,7 @@ func (ht *serverHandlerTransport) do(fn func()) error {
 	}
 }
 
-func (ht *serverHandlerTransport) WriteStatus(s *Stream, statusCode codes.Code, statusDesc string) error {
+func (ht *serverHandlerTransport) WriteStatus(s *Stream, st *status.Status) error {
 	err := ht.do(func() {
 		ht.writeCommonHeaders(s)
 
@@ -192,10 +193,13 @@ func (ht *serverHandlerTransport) WriteStatus(s *Stream, statusCode codes.Code,
 		ht.rw.(http.Flusher).Flush()
 
 		h := ht.rw.Header()
-		h.Set("Grpc-Status", fmt.Sprintf("%d", statusCode))
-		if statusDesc != "" {
-			h.Set("Grpc-Message", encodeGrpcMessage(statusDesc))
+		h.Set("Grpc-Status", fmt.Sprintf("%d", st.Code()))
+		if m := st.Message(); m != "" {
+			h.Set("Grpc-Message", encodeGrpcMessage(m))
 		}
+
+		// TODO: Support Grpc-Status-Details-Bin
+
 		if md := s.Trailer(); len(md) > 0 {
 			for k, vv := range md {
 				// Clients don't tolerate reading restricted headers after some non restricted ones were sent.
@@ -234,6 +238,7 @@ func (ht *serverHandlerTransport) writeCommonHeaders(s *Stream) {
 	// and https://golang.org/pkg/net/http/#example_ResponseWriter_trailers
 	h.Add("Trailer", "Grpc-Status")
 	h.Add("Trailer", "Grpc-Message")
+	// TODO: Support Grpc-Status-Details-Bin
 
 	if s.sendCompress != "" {
 		h.Set("Grpc-Encoding", s.sendCompress)
@@ -268,7 +273,7 @@ func (ht *serverHandlerTransport) WriteHeader(s *Stream, md metadata.MD) error {
 	})
 }
 
-func (ht *serverHandlerTransport) HandleStreams(startStream func(*Stream)) {
+func (ht *serverHandlerTransport) HandleStreams(startStream func(*Stream), traceCtx func(context.Context, string) context.Context) {
 	// With this transport type there will be exactly 1 stream: this HTTP request.
 
 	var ctx context.Context
@@ -314,7 +319,7 @@ func (ht *serverHandlerTransport) HandleStreams(startStream func(*Stream)) {
 	if req.TLS != nil {
 		pr.AuthInfo = credentials.TLSInfo{State: *req.TLS}
 	}
-	ctx = metadata.NewContext(ctx, ht.headerMD)
+	ctx = metadata.NewIncomingContext(ctx, ht.headerMD)
 	ctx = peer.NewContext(ctx, pr)
 	s.ctx = newContextWithStream(ctx, s)
 	s.dec = &recvBufferReader{ctx: s.ctx, recv: s.buf}

vendor/google.golang.org/grpc/transport/http2_client.go

@@ -35,12 +35,12 @@ package transport
 
 import (
 	"bytes"
-	"fmt"
 	"io"
 	"math"
 	"net"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"golang.org/x/net/context"
@@ -49,17 +49,24 @@ import (
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
+	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
 )
 
 // http2Client implements the ClientTransport interface with HTTP2.
 type http2Client struct {
-	target    string // server name/addr
-	userAgent string
-	conn      net.Conn             // underlying communication channel
-	authInfo  credentials.AuthInfo // auth info about the connection
-	nextID    uint32               // the next stream ID to be used
+	ctx        context.Context
+	target     string // server name/addr
+	userAgent  string
+	md         interface{}
+	conn       net.Conn // underlying communication channel
+	remoteAddr net.Addr
+	localAddr  net.Addr
+	authInfo   credentials.AuthInfo // auth info about the connection
+	nextID     uint32               // the next stream ID to be used
 
 	// writableChan synchronizes write access to the transport.
 	// A writer acquires the write lock by sending a value on writableChan
@@ -75,6 +82,8 @@ type http2Client struct {
 	// goAway is closed to notify the upper layer (i.e., addrConn.transportMonitor)
 	// that the server sent GoAway on this transport.
 	goAway chan struct{}
+	// awakenKeepalive is used to wake up keepalive when after it has gone dormant.
+	awakenKeepalive chan struct{}
 
 	framer *framer
 	hBuf   *bytes.Buffer  // the buffer for HPACK encoding
@@ -94,6 +103,13 @@ type http2Client struct {
 
 	creds []credentials.PerRPCCredentials
 
+	// Boolean to keep track of reading activity on transport.
+	// 1 is true and 0 is false.
+	activity uint32 // Accessed atomically.
+	kp       keepalive.ClientParameters
+
+	statsHandler stats.Handler
+
 	mu            sync.Mutex     // guard the following variables
 	state         transportState // the state of underlying connection
 	activeStreams map[uint32]*Stream
@@ -105,9 +121,12 @@ type http2Client struct {
 	goAwayID uint32
 	// prevGoAway ID records the Last-Stream-ID in the previous GOAway frame.
 	prevGoAwayID uint32
+	// goAwayReason records the http2.ErrCode and debug data received with the
+	// GoAway frame.
+	goAwayReason GoAwayReason
 }
 
-func dial(fn func(context.Context, string) (net.Conn, error), ctx context.Context, addr string) (net.Conn, error) {
+func dial(ctx context.Context, fn func(context.Context, string) (net.Conn, error), addr string) (net.Conn, error) {
 	if fn != nil {
 		return fn(ctx, addr)
 	}
@@ -145,10 +164,13 @@ func isTemporary(err error) bool {
 // newHTTP2Client constructs a connected ClientTransport to addr based on HTTP2
 // and starts to receive messages on it. Non-nil error returns if construction
 // fails.
-func newHTTP2Client(ctx context.Context, addr string, opts ConnectOptions) (_ ClientTransport, err error) {
+func newHTTP2Client(ctx context.Context, addr TargetInfo, opts ConnectOptions) (_ ClientTransport, err error) {
 	scheme := "http"
-	conn, err := dial(opts.Dialer, ctx, addr)
+	conn, err := dial(ctx, opts.Dialer, addr.Addr)
 	if err != nil {
+		if opts.FailOnNonTempDialError {
+			return nil, connectionErrorf(isTemporary(err), err, "transport: %v", err)
+		}
 		return nil, connectionErrorf(true, err, "transport: %v", err)
 	}
 	// Any further errors will close the underlying connection
@@ -160,7 +182,7 @@ func newHTTP2Client(ctx context.Context, addr string, opts ConnectOptions) (_ Cl
 	var authInfo credentials.AuthInfo
 	if creds := opts.TransportCredentials; creds != nil {
 		scheme = "https"
-		conn, authInfo, err = creds.ClientHandshake(ctx, addr, conn)
+		conn, authInfo, err = creds.ClientHandshake(ctx, addr.Addr, conn)
 		if err != nil {
 			// Credentials handshake errors are typically considered permanent
 			// to avoid retrying on e.g. bad certificates.
@@ -168,22 +190,31 @@ func newHTTP2Client(ctx context.Context, addr string, opts ConnectOptions) (_ Cl
 			return nil, connectionErrorf(temp, err, "transport: %v", err)
 		}
 	}
-	ua := primaryUA
-	if opts.UserAgent != "" {
-		ua = opts.UserAgent + " " + ua
+	kp := opts.KeepaliveParams
+	// Validate keepalive parameters.
+	if kp.Time == 0 {
+		kp.Time = defaultClientKeepaliveTime
+	}
+	if kp.Timeout == 0 {
+		kp.Timeout = defaultClientKeepaliveTimeout
 	}
 	var buf bytes.Buffer
 	t := &http2Client{
-		target:    addr,
-		userAgent: ua,
-		conn:      conn,
-		authInfo:  authInfo,
+		ctx:        ctx,
+		target:     addr.Addr,
+		userAgent:  opts.UserAgent,
+		md:         addr.Metadata,
+		conn:       conn,
+		remoteAddr: conn.RemoteAddr(),
+		localAddr:  conn.LocalAddr(),
+		authInfo:   authInfo,
 		// The client initiated stream id is odd starting from 1.
 		nextID:          1,
 		writableChan:    make(chan int, 1),
 		shutdownChan:    make(chan struct{}),
 		errorChan:       make(chan struct{}),
 		goAway:          make(chan struct{}),
+		awakenKeepalive: make(chan struct{}, 1),
 		framer:          newFramer(conn),
 		hBuf:            &buf,
 		hEnc:            hpack.NewEncoder(&buf),
@@ -194,8 +225,24 @@ func newHTTP2Client(ctx context.Context, addr string, opts ConnectOptions) (_ Cl
 		state:           reachable,
 		activeStreams:   make(map[uint32]*Stream),
 		creds:           opts.PerRPCCredentials,
-		maxStreams:      math.MaxInt32,
+		maxStreams:      defaultMaxStreamsClient,
+		streamsQuota:    newQuotaPool(defaultMaxStreamsClient),
 		streamSendQuota: defaultWindowSize,
+		kp:              kp,
+		statsHandler:    opts.StatsHandler,
+	}
+	// Make sure awakenKeepalive can't be written upon.
+	// keepalive routine will make it writable, if need be.
+	t.awakenKeepalive <- struct{}{}
+	if t.statsHandler != nil {
+		t.ctx = t.statsHandler.TagConn(t.ctx, &stats.ConnTagInfo{
+			RemoteAddr: t.remoteAddr,
+			LocalAddr:  t.localAddr,
+		})
+		connBegin := &stats.ConnBegin{
+			Client: true,
+		}
+		t.statsHandler.HandleConn(t.ctx, connBegin)
 	}
 	// Start the reader goroutine for incoming message. Each transport has
 	// a dedicated goroutine which reads HTTP2 frame from network. Then it
@@ -231,6 +278,9 @@ func newHTTP2Client(ctx context.Context, addr string, opts ConnectOptions) (_ Cl
 		}
 	}
 	go t.controller()
+	if t.kp.Time != infinity {
+		go t.keepalive()
+	}
 	t.writableChan <- 0
 	return t, nil
 }
@@ -264,16 +314,17 @@ func (t *http2Client) newStream(ctx context.Context, callHdr *CallHdr) *Stream {
 	return s
 }
 
-// NewStream creates a stream and register it into the transport as "active"
+// NewStream creates a stream and registers it into the transport as "active"
 // streams.
 func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Stream, err error) {
 	pr := &peer.Peer{
-		Addr: t.conn.RemoteAddr(),
+		Addr: t.remoteAddr,
 	}
 	// Attach Auth info if there is any.
 	if t.authInfo != nil {
 		pr.AuthInfo = t.authInfo
 	}
+	userCtx := ctx
 	ctx = peer.NewContext(ctx, pr)
 	authData := make(map[string]string)
 	for _, c := range t.creds {
@@ -311,21 +362,18 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 		t.mu.Unlock()
 		return nil, ErrConnClosing
 	}
-	checkStreamsQuota := t.streamsQuota != nil
 	t.mu.Unlock()
-	if checkStreamsQuota {
-		sq, err := wait(ctx, nil, nil, t.shutdownChan, t.streamsQuota.acquire())
-		if err != nil {
-			return nil, err
-		}
-		// Returns the quota balance back.
-		if sq > 1 {
-			t.streamsQuota.add(sq - 1)
-		}
+	sq, err := wait(ctx, nil, nil, t.shutdownChan, t.streamsQuota.acquire())
+	if err != nil {
+		return nil, err
+	}
+	// Returns the quota balance back.
+	if sq > 1 {
+		t.streamsQuota.add(sq - 1)
 	}
 	if _, err := wait(ctx, nil, nil, t.shutdownChan, t.writableChan); err != nil {
 		// Return the quota back now because there is no stream returned to the caller.
-		if _, ok := err.(StreamError); ok && checkStreamsQuota {
+		if _, ok := err.(StreamError); ok {
 			t.streamsQuota.add(1)
 		}
 		return nil, err
@@ -333,9 +381,7 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 	t.mu.Lock()
 	if t.state == draining {
 		t.mu.Unlock()
-		if checkStreamsQuota {
-			t.streamsQuota.add(1)
-		}
+		t.streamsQuota.add(1)
 		// Need to make t writable again so that the rpc in flight can still proceed.
 		t.writableChan <- 0
 		return nil, ErrStreamDrain
@@ -345,18 +391,19 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 		return nil, ErrConnClosing
 	}
 	s := t.newStream(ctx, callHdr)
+	s.clientStatsCtx = userCtx
 	t.activeStreams[s.id] = s
+	// If the number of active streams change from 0 to 1, then check if keepalive
+	// has gone dormant. If so, wake it up.
+	if len(t.activeStreams) == 1 {
+		select {
+		case t.awakenKeepalive <- struct{}{}:
+			t.framer.writePing(false, false, [8]byte{})
+		default:
+		}
+	}
 
-	// This stream is not counted when applySetings(...) initialize t.streamsQuota.
-	// Reset t.streamsQuota to the right value.
-	var reset bool
-	if !checkStreamsQuota && t.streamsQuota != nil {
-		reset = true
-	}
 	t.mu.Unlock()
-	if reset {
-		t.streamsQuota.reset(-1)
-	}
 
 	// HPACK encodes various headers. Note that once WriteField(...) is
 	// called, the corresponding headers/continuation frame has to be sent
@@ -388,7 +435,7 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 		hasMD      bool
 		endHeaders bool
 	)
-	if md, ok := metadata.FromContext(ctx); ok {
+	if md, ok := metadata.FromOutgoingContext(ctx); ok {
 		hasMD = true
 		for k, v := range md {
 			// HTTP doesn't allow you to set pseudoheaders after non pseudoheaders were set.
@@ -400,7 +447,18 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 			}
 		}
 	}
+	if md, ok := t.md.(*metadata.MD); ok {
+		for k, v := range *md {
+			if isReservedHeader(k) {
+				continue
+			}
+			for _, entry := range v {
+				t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: entry})
+			}
+		}
+	}
 	first := true
+	bufLen := t.hBuf.Len()
 	// Sends the headers in a single batch even when they span multiple frames.
 	for !endHeaders {
 		size := t.hBuf.Len()
@@ -435,6 +493,17 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 			return nil, connectionErrorf(true, err, "transport: %v", err)
 		}
 	}
+	if t.statsHandler != nil {
+		outHeader := &stats.OutHeader{
+			Client:      true,
+			WireLength:  bufLen,
+			FullMethod:  callHdr.Method,
+			RemoteAddr:  t.remoteAddr,
+			LocalAddr:   t.localAddr,
+			Compression: callHdr.SendCompress,
+		}
+		t.statsHandler.HandleRPC(s.clientStatsCtx, outHeader)
+	}
 	t.writableChan <- 0
 	return s, nil
 }
@@ -442,15 +511,11 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 // CloseStream clears the footprint of a stream when the stream is not needed any more.
 // This must not be executed in reader's goroutine.
 func (t *http2Client) CloseStream(s *Stream, err error) {
-	var updateStreams bool
 	t.mu.Lock()
 	if t.activeStreams == nil {
 		t.mu.Unlock()
 		return
 	}
-	if t.streamsQuota != nil {
-		updateStreams = true
-	}
 	delete(t.activeStreams, s.id)
 	if t.state == draining && len(t.activeStreams) == 0 {
 		// The transport is draining and s is the last live stream on t.
@@ -459,10 +524,27 @@ func (t *http2Client) CloseStream(s *Stream, err error) {
 		return
 	}
 	t.mu.Unlock()
-	if updateStreams {
-		t.streamsQuota.add(1)
-	}
+	// rstStream is true in case the stream is being closed at the client-side
+	// and the server needs to be intimated about it by sending a RST_STREAM
+	// frame.
+	// To make sure this frame is written to the wire before the headers of the
+	// next stream waiting for streamsQuota, we add to streamsQuota pool only
+	// after having acquired the writableChan to send RST_STREAM out (look at
+	// the controller() routine).
+	var rstStream bool
+	var rstError http2.ErrCode
+	defer func() {
+		// In case, the client doesn't have to send RST_STREAM to server
+		// we can safely add back to streamsQuota pool now.
+		if !rstStream {
+			t.streamsQuota.add(1)
+			return
+		}
+		t.controlBuf.put(&resetStream{s.id, rstError})
+	}()
 	s.mu.Lock()
+	rstStream = s.rstStream
+	rstError = s.rstError
 	if q := s.fc.resetPendingData(); q > 0 {
 		if n := t.fc.onRead(q); n > 0 {
 			t.controlBuf.put(&windowUpdate{0, n})
@@ -478,8 +560,9 @@ func (t *http2Client) CloseStream(s *Stream, err error) {
 	}
 	s.state = streamDone
 	s.mu.Unlock()
-	if se, ok := err.(StreamError); ok && se.Code != codes.DeadlineExceeded {
-		t.controlBuf.put(&resetStream{s.id, http2.ErrCodeCancel})
+	if _, ok := err.(StreamError); ok {
+		rstStream = true
+		rstError = http2.ErrCodeCancel
 	}
 }
 
@@ -513,6 +596,12 @@ func (t *http2Client) Close() (err error) {
 		s.mu.Unlock()
 		s.write(recvMsg{err: ErrConnClosing})
 	}
+	if t.statsHandler != nil {
+		connEnd := &stats.ConnEnd{
+			Client: true,
+		}
+		t.statsHandler.HandleConn(t.ctx, connEnd)
+	}
 	return
 }
 
@@ -570,19 +659,14 @@ func (t *http2Client) Write(s *Stream, data []byte, opts *Options) error {
 		var p []byte
 		if r.Len() > 0 {
 			size := http2MaxFrameLen
-			s.sendQuotaPool.add(0)
 			// Wait until the stream has some quota to send the data.
 			sq, err := wait(s.ctx, s.done, s.goAway, t.shutdownChan, s.sendQuotaPool.acquire())
 			if err != nil {
 				return err
 			}
-			t.sendQuotaPool.add(0)
 			// Wait until the transport has some quota to send the data.
 			tq, err := wait(s.ctx, s.done, s.goAway, t.shutdownChan, t.sendQuotaPool.acquire())
 			if err != nil {
-				if _, ok := err.(StreamError); ok || err == io.EOF {
-					t.sendQuotaPool.cancel()
-				}
 				return err
 			}
 			if sq < size {
@@ -692,7 +776,7 @@ func (t *http2Client) updateWindow(s *Stream, n uint32) {
 }
 
 func (t *http2Client) handleData(f *http2.DataFrame) {
-	size := len(f.Data())
+	size := f.Header().Length
 	if err := t.fc.onData(uint32(size)); err != nil {
 		t.notifyError(connectionErrorf(true, err, "%v", err))
 		return
@@ -706,6 +790,11 @@ func (t *http2Client) handleData(f *http2.DataFrame) {
 		return
 	}
 	if size > 0 {
+		if f.Header().Flags.Has(http2.FlagDataPadded) {
+			if w := t.fc.onRead(uint32(size) - uint32(len(f.Data()))); w > 0 {
+				t.controlBuf.put(&windowUpdate{0, w})
+			}
+		}
 		s.mu.Lock()
 		if s.state == streamDone {
 			s.mu.Unlock()
@@ -716,22 +805,27 @@ func (t *http2Client) handleData(f *http2.DataFrame) {
 			return
 		}
 		if err := s.fc.onData(uint32(size)); err != nil {
-			s.state = streamDone
-			s.statusCode = codes.Internal
-			s.statusDesc = err.Error()
-			close(s.done)
+			s.rstStream = true
+			s.rstError = http2.ErrCodeFlowControl
+			s.finish(status.New(codes.Internal, err.Error()))
 			s.mu.Unlock()
 			s.write(recvMsg{err: io.EOF})
-			t.controlBuf.put(&resetStream{s.id, http2.ErrCodeFlowControl})
 			return
 		}
+		if f.Header().Flags.Has(http2.FlagDataPadded) {
+			if w := s.fc.onRead(uint32(size) - uint32(len(f.Data()))); w > 0 {
+				t.controlBuf.put(&windowUpdate{s.id, w})
+			}
+		}
 		s.mu.Unlock()
 		// TODO(bradfitz, zhaoq): A copy is required here because there is no
 		// guarantee f.Data() is consumed before the arrival of next frame.
 		// Can this copy be eliminated?
-		data := make([]byte, size)
-		copy(data, f.Data())
-		s.write(recvMsg{data: data})
+		if len(f.Data()) > 0 {
+			data := make([]byte, len(f.Data()))
+			copy(data, f.Data())
+			s.write(recvMsg{data: data})
+		}
 	}
 	// The server has closed the stream without sending trailers.  Record that
 	// the read direction is closed, and set the status appropriately.
@@ -741,10 +835,7 @@ func (t *http2Client) handleData(f *http2.DataFrame) {
 			s.mu.Unlock()
 			return
 		}
-		s.state = streamDone
-		s.statusCode = codes.Internal
-		s.statusDesc = "server closed the stream without sending trailers"
-		close(s.done)
+		s.finish(status.New(codes.Internal, "server closed the stream without sending trailers"))
 		s.mu.Unlock()
 		s.write(recvMsg{err: io.EOF})
 	}
@@ -760,18 +851,16 @@ func (t *http2Client) handleRSTStream(f *http2.RSTStreamFrame) {
 		s.mu.Unlock()
 		return
 	}
-	s.state = streamDone
 	if !s.headerDone {
 		close(s.headerChan)
 		s.headerDone = true
 	}
-	s.statusCode, ok = http2ErrConvTab[http2.ErrCode(f.ErrCode)]
+	statusCode, ok := http2ErrConvTab[http2.ErrCode(f.ErrCode)]
 	if !ok {
 		grpclog.Println("transport: http2Client.handleRSTStream found no mapped gRPC status for the received http2 error ", f.ErrCode)
-		s.statusCode = codes.Unknown
+		statusCode = codes.Unknown
 	}
-	s.statusDesc = fmt.Sprintf("stream terminated by RST_STREAM with error code: %d", f.ErrCode)
-	close(s.done)
+	s.finish(status.Newf(statusCode, "stream terminated by RST_STREAM with error code: %d", f.ErrCode))
 	s.mu.Unlock()
 	s.write(recvMsg{err: io.EOF})
 }
@@ -790,12 +879,18 @@ func (t *http2Client) handleSettings(f *http2.SettingsFrame) {
 }
 
 func (t *http2Client) handlePing(f *http2.PingFrame) {
+	if f.IsAck() { // Do nothing.
+		return
+	}
 	pingAck := &ping{ack: true}
 	copy(pingAck.data[:], f.Data[:])
 	t.controlBuf.put(pingAck)
 }
 
 func (t *http2Client) handleGoAway(f *http2.GoAwayFrame) {
+	if f.ErrCode == http2.ErrCodeEnhanceYourCalm {
+		grpclog.Printf("Client received GoAway with http2.ErrCodeEnhanceYourCalm.")
+	}
 	t.mu.Lock()
 	if t.state == reachable || t.state == draining {
 		if f.LastStreamID > 0 && f.LastStreamID%2 != 1 {
@@ -817,6 +912,7 @@ func (t *http2Client) handleGoAway(f *http2.GoAwayFrame) {
 			t.mu.Unlock()
 			return
 		default:
+			t.setGoAwayReason(f)
 		}
 		t.goAwayID = f.LastStreamID
 		close(t.goAway)
@@ -824,6 +920,26 @@ func (t *http2Client) handleGoAway(f *http2.GoAwayFrame) {
 	t.mu.Unlock()
 }
 
+// setGoAwayReason sets the value of t.goAwayReason based
+// on the GoAway frame received.
+// It expects a lock on transport's mutext to be held by
+// the caller.
+func (t *http2Client) setGoAwayReason(f *http2.GoAwayFrame) {
+	t.goAwayReason = NoReason
+	switch f.ErrCode {
+	case http2.ErrCodeEnhanceYourCalm:
+		if string(f.DebugData()) == "too_many_pings" {
+			t.goAwayReason = TooManyPings
+		}
+	}
+}
+
+func (t *http2Client) GetGoAwayReason() GoAwayReason {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	return t.goAwayReason
+}
+
 func (t *http2Client) handleWindowUpdate(f *http2.WindowUpdateFrame) {
 	id := f.Header().StreamID
 	incr := f.Increment
@@ -844,21 +960,38 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 	}
 	var state decodeState
 	for _, hf := range frame.Fields {
-		state.processHeaderField(hf)
-	}
-	if state.err != nil {
-		s.mu.Lock()
-		if !s.headerDone {
-			close(s.headerChan)
-			s.headerDone = true
+		if err := state.processHeaderField(hf); err != nil {
+			s.mu.Lock()
+			if !s.headerDone {
+				close(s.headerChan)
+				s.headerDone = true
+			}
+			s.mu.Unlock()
+			s.write(recvMsg{err: err})
+			// Something wrong. Stops reading even when there is remaining.
+			return
 		}
-		s.mu.Unlock()
-		s.write(recvMsg{err: state.err})
-		// Something wrong. Stops reading even when there is remaining.
-		return
 	}
 
 	endStream := frame.StreamEnded()
+	var isHeader bool
+	defer func() {
+		if t.statsHandler != nil {
+			if isHeader {
+				inHeader := &stats.InHeader{
+					Client:     true,
+					WireLength: int(frame.Header().Length),
+				}
+				t.statsHandler.HandleRPC(s.clientStatsCtx, inHeader)
+			} else {
+				inTrailer := &stats.InTrailer{
+					Client:     true,
+					WireLength: int(frame.Header().Length),
+				}
+				t.statsHandler.HandleRPC(s.clientStatsCtx, inTrailer)
+			}
+		}
+	}()
 
 	s.mu.Lock()
 	if !endStream {
@@ -870,6 +1003,7 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 		}
 		close(s.headerChan)
 		s.headerDone = true
+		isHeader = true
 	}
 	if !endStream || s.state == streamDone {
 		s.mu.Unlock()
@@ -879,10 +1013,7 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 	if len(state.mdata) > 0 {
 		s.trailer = state.mdata
 	}
-	s.statusCode = state.statusCode
-	s.statusDesc = state.statusDesc
-	close(s.done)
-	s.state = streamDone
+	s.finish(state.status())
 	s.mu.Unlock()
 	s.write(recvMsg{err: io.EOF})
 }
@@ -910,6 +1041,7 @@ func (t *http2Client) reader() {
 		t.notifyError(err)
 		return
 	}
+	atomic.CompareAndSwapUint32(&t.activity, 0, 1)
 	sf, ok := frame.(*http2.SettingsFrame)
 	if !ok {
 		t.notifyError(err)
@@ -920,6 +1052,7 @@ func (t *http2Client) reader() {
 	// loop to keep reading incoming messages on this transport.
 	for {
 		frame, err := t.framer.readFrame()
+		atomic.CompareAndSwapUint32(&t.activity, 0, 1)
 		if err != nil {
 			// Abort an active stream if the http2.Framer returns a
 			// http2.StreamError. This can happen only if the server's response
@@ -971,21 +1104,15 @@ func (t *http2Client) applySettings(ss []http2.Setting) {
 				s.Val = math.MaxInt32
 			}
 			t.mu.Lock()
-			reset := t.streamsQuota != nil
-			if !reset {
-				t.streamsQuota = newQuotaPool(int(s.Val) - len(t.activeStreams))
-			}
 			ms := t.maxStreams
 			t.maxStreams = int(s.Val)
 			t.mu.Unlock()
-			if reset {
-				t.streamsQuota.reset(int(s.Val) - ms)
-			}
+			t.streamsQuota.add(int(s.Val) - ms)
 		case http2.SettingInitialWindowSize:
 			t.mu.Lock()
 			for _, stream := range t.activeStreams {
 				// Adjust the sending quota for each stream.
-				stream.sendQuotaPool.reset(int(s.Val - t.streamSendQuota))
+				stream.sendQuotaPool.add(int(s.Val - t.streamSendQuota))
 			}
 			t.streamSendQuota = s.Val
 			t.mu.Unlock()
@@ -1013,6 +1140,12 @@ func (t *http2Client) controller() {
 						t.framer.writeSettings(true, i.ss...)
 					}
 				case *resetStream:
+					// If the server needs to be to intimated about stream closing,
+					// then we need to make sure the RST_STREAM frame is written to
+					// the wire before the headers of the next stream waiting on
+					// streamQuota. We ensure this by adding to the streamsQuota pool
+					// only after having acquired the writableChan to send RST_STREAM.
+					t.streamsQuota.add(1)
 					t.framer.writeRSTStream(true, i.streamID, i.code)
 				case *flushIO:
 					t.framer.flushWrite()
@@ -1032,6 +1165,61 @@ func (t *http2Client) controller() {
 	}
 }
 
+// keepalive running in a separate goroutune makes sure the connection is alive by sending pings.
+func (t *http2Client) keepalive() {
+	p := &ping{data: [8]byte{}}
+	timer := time.NewTimer(t.kp.Time)
+	for {
+		select {
+		case <-timer.C:
+			if atomic.CompareAndSwapUint32(&t.activity, 1, 0) {
+				timer.Reset(t.kp.Time)
+				continue
+			}
+			// Check if keepalive should go dormant.
+			t.mu.Lock()
+			if len(t.activeStreams) < 1 && !t.kp.PermitWithoutStream {
+				// Make awakenKeepalive writable.
+				<-t.awakenKeepalive
+				t.mu.Unlock()
+				select {
+				case <-t.awakenKeepalive:
+					// If the control gets here a ping has been sent
+					// need to reset the timer with keepalive.Timeout.
+				case <-t.shutdownChan:
+					return
+				}
+			} else {
+				t.mu.Unlock()
+				// Send ping.
+				t.controlBuf.put(p)
+			}
+
+			// By the time control gets here a ping has been sent one way or the other.
+			timer.Reset(t.kp.Timeout)
+			select {
+			case <-timer.C:
+				if atomic.CompareAndSwapUint32(&t.activity, 1, 0) {
+					timer.Reset(t.kp.Time)
+					continue
+				}
+				t.Close()
+				return
+			case <-t.shutdownChan:
+				if !timer.Stop() {
+					<-timer.C
+				}
+				return
+			}
+		case <-t.shutdownChan:
+			if !timer.Stop() {
+				<-timer.C
+			}
+			return
+		}
+	}
+}
+
 func (t *http2Client) Error() <-chan struct{} {
 	return t.errorChan
 }

vendor/google.golang.org/grpc/transport/http2_server.go

@@ -38,18 +38,26 @@ import (
 	"errors"
 	"io"
 	"math"
+	"math/rand"
 	"net"
 	"strconv"
 	"sync"
+	"sync/atomic"
+	"time"
 
+	"github.com/golang/protobuf/proto"
 	"golang.org/x/net/context"
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/hpack"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
+	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
+	"google.golang.org/grpc/tap"
 )
 
 // ErrIllegalHeaderWrite indicates that setting header is illegal because of
@@ -58,9 +66,13 @@ var ErrIllegalHeaderWrite = errors.New("transport: the stream is done or WriteHe
 
 // http2Server implements the ServerTransport interface with HTTP2.
 type http2Server struct {
+	ctx         context.Context
 	conn        net.Conn
+	remoteAddr  net.Addr
+	localAddr   net.Addr
 	maxStreamID uint32               // max stream ID ever seen
 	authInfo    credentials.AuthInfo // auth info about the connection
+	inTapHandle tap.ServerInHandle
 	// writableChan synchronizes write access to the transport.
 	// A writer acquires the write lock by receiving a value on writableChan
 	// and releases it by sending on writableChan.
@@ -82,21 +94,46 @@ type http2Server struct {
 	// sendQuotaPool provides flow control to outbound message.
 	sendQuotaPool *quotaPool
 
+	stats stats.Handler
+
+	// Flag to keep track of reading activity on transport.
+	// 1 is true and 0 is false.
+	activity uint32 // Accessed atomically.
+	// Keepalive and max-age parameters for the server.
+	kp keepalive.ServerParameters
+
+	// Keepalive enforcement policy.
+	kep keepalive.EnforcementPolicy
+	// The time instance last ping was received.
+	lastPingAt time.Time
+	// Number of times the client has violated keepalive ping policy so far.
+	pingStrikes uint8
+	// Flag to signify that number of ping strikes should be reset to 0.
+	// This is set whenever data or header frames are sent.
+	// 1 means yes.
+	resetPingStrikes uint32 // Accessed atomically.
+
 	mu            sync.Mutex // guard the following
 	state         transportState
 	activeStreams map[uint32]*Stream
 	// the per-stream outbound flow control window size set by the peer.
 	streamSendQuota uint32
+	// idle is the time instant when the connection went idle.
+	// This is either the begining of the connection or when the number of
+	// RPCs go down to 0.
+	// When the connection is busy, this value is set to 0.
+	idle time.Time
 }
 
 // newHTTP2Server constructs a ServerTransport based on HTTP2. ConnectionError is
 // returned if something goes wrong.
-func newHTTP2Server(conn net.Conn, maxStreams uint32, authInfo credentials.AuthInfo) (_ ServerTransport, err error) {
+func newHTTP2Server(conn net.Conn, config *ServerConfig) (_ ServerTransport, err error) {
 	framer := newFramer(conn)
 	// Send initial settings as connection preface to client.
 	var settings []http2.Setting
 	// TODO(zhaoq): Have a better way to signal "no limit" because 0 is
 	// permitted in the HTTP2 spec.
+	maxStreams := config.MaxStreams
 	if maxStreams == 0 {
 		maxStreams = math.MaxUint32
 	} else {
@@ -119,14 +156,40 @@ func newHTTP2Server(conn net.Conn, maxStreams uint32, authInfo credentials.AuthI
 			return nil, connectionErrorf(true, err, "transport: %v", err)
 		}
 	}
+	kp := config.KeepaliveParams
+	if kp.MaxConnectionIdle == 0 {
+		kp.MaxConnectionIdle = defaultMaxConnectionIdle
+	}
+	if kp.MaxConnectionAge == 0 {
+		kp.MaxConnectionAge = defaultMaxConnectionAge
+	}
+	// Add a jitter to MaxConnectionAge.
+	kp.MaxConnectionAge += getJitter(kp.MaxConnectionAge)
+	if kp.MaxConnectionAgeGrace == 0 {
+		kp.MaxConnectionAgeGrace = defaultMaxConnectionAgeGrace
+	}
+	if kp.Time == 0 {
+		kp.Time = defaultServerKeepaliveTime
+	}
+	if kp.Timeout == 0 {
+		kp.Timeout = defaultServerKeepaliveTimeout
+	}
+	kep := config.KeepalivePolicy
+	if kep.MinTime == 0 {
+		kep.MinTime = defaultKeepalivePolicyMinTime
+	}
 	var buf bytes.Buffer
 	t := &http2Server{
+		ctx:             context.Background(),
 		conn:            conn,
-		authInfo:        authInfo,
+		remoteAddr:      conn.RemoteAddr(),
+		localAddr:       conn.LocalAddr(),
+		authInfo:        config.AuthInfo,
 		framer:          framer,
 		hBuf:            &buf,
 		hEnc:            hpack.NewEncoder(&buf),
 		maxStreams:      maxStreams,
+		inTapHandle:     config.InTapHandle,
 		controlBuf:      newRecvBuffer(),
 		fc:              &inFlow{limit: initialConnWindowSize},
 		sendQuotaPool:   newQuotaPool(defaultWindowSize),
@@ -135,14 +198,27 @@ func newHTTP2Server(conn net.Conn, maxStreams uint32, authInfo credentials.AuthI
 		shutdownChan:    make(chan struct{}),
 		activeStreams:   make(map[uint32]*Stream),
 		streamSendQuota: defaultWindowSize,
+		stats:           config.StatsHandler,
+		kp:              kp,
+		idle:            time.Now(),
+		kep:             kep,
+	}
+	if t.stats != nil {
+		t.ctx = t.stats.TagConn(t.ctx, &stats.ConnTagInfo{
+			RemoteAddr: t.remoteAddr,
+			LocalAddr:  t.localAddr,
+		})
+		connBegin := &stats.ConnBegin{}
+		t.stats.HandleConn(t.ctx, connBegin)
 	}
 	go t.controller()
+	go t.keepalive()
 	t.writableChan <- 0
 	return t, nil
 }
 
 // operateHeader takes action on the decoded headers.
-func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(*Stream)) (close bool) {
+func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(*Stream), traceCtx func(context.Context, string) context.Context) (close bool) {
 	buf := newRecvBuffer()
 	s := &Stream{
 		id:  frame.Header().StreamID,
@@ -153,13 +229,12 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 
 	var state decodeState
 	for _, hf := range frame.Fields {
-		state.processHeaderField(hf)
-	}
-	if err := state.err; err != nil {
-		if se, ok := err.(StreamError); ok {
-			t.controlBuf.put(&resetStream{s.id, statusCodeConvTab[se.Code]})
+		if err := state.processHeaderField(hf); err != nil {
+			if se, ok := err.(StreamError); ok {
+				t.controlBuf.put(&resetStream{s.id, statusCodeConvTab[se.Code]})
+			}
+			return
 		}
-		return
 	}
 
 	if frame.StreamEnded() {
@@ -168,12 +243,12 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 	}
 	s.recvCompress = state.encoding
 	if state.timeoutSet {
-		s.ctx, s.cancel = context.WithTimeout(context.TODO(), state.timeout)
+		s.ctx, s.cancel = context.WithTimeout(t.ctx, state.timeout)
 	} else {
-		s.ctx, s.cancel = context.WithCancel(context.TODO())
+		s.ctx, s.cancel = context.WithCancel(t.ctx)
 	}
 	pr := &peer.Peer{
-		Addr: t.conn.RemoteAddr(),
+		Addr: t.remoteAddr,
 	}
 	// Attach Auth info if there is any.
 	if t.authInfo != nil {
@@ -186,7 +261,7 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 	s.ctx = newContextWithStream(s.ctx, s)
 	// Attach the received metadata to the context.
 	if len(state.mdata) > 0 {
-		s.ctx = metadata.NewContext(s.ctx, state.mdata)
+		s.ctx = metadata.NewIncomingContext(s.ctx, state.mdata)
 	}
 
 	s.dec = &recvBufferReader{
@@ -195,6 +270,18 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 	}
 	s.recvCompress = state.encoding
 	s.method = state.method
+	if t.inTapHandle != nil {
+		var err error
+		info := &tap.Info{
+			FullMethodName: state.method,
+		}
+		s.ctx, err = t.inTapHandle(s.ctx, info)
+		if err != nil {
+			// TODO: Log the real error.
+			t.controlBuf.put(&resetStream{s.id, http2.ErrCodeRefusedStream})
+			return
+		}
+	}
 	t.mu.Lock()
 	if t.state != reachable {
 		t.mu.Unlock()
@@ -214,17 +301,33 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 	t.maxStreamID = s.id
 	s.sendQuotaPool = newQuotaPool(int(t.streamSendQuota))
 	t.activeStreams[s.id] = s
+	if len(t.activeStreams) == 1 {
+		t.idle = time.Time{}
+	}
 	t.mu.Unlock()
 	s.windowHandler = func(n int) {
 		t.updateWindow(s, uint32(n))
 	}
+	s.ctx = traceCtx(s.ctx, s.method)
+	if t.stats != nil {
+		s.ctx = t.stats.TagRPC(s.ctx, &stats.RPCTagInfo{FullMethodName: s.method})
+		inHeader := &stats.InHeader{
+			FullMethod:  s.method,
+			RemoteAddr:  t.remoteAddr,
+			LocalAddr:   t.localAddr,
+			Compression: s.recvCompress,
+			WireLength:  int(frame.Header().Length),
+		}
+		t.stats.HandleRPC(s.ctx, inHeader)
+	}
 	handle(s)
 	return
 }
 
 // HandleStreams receives incoming streams using the given handler. This is
 // typically run in a separate goroutine.
-func (t *http2Server) HandleStreams(handle func(*Stream)) {
+// traceCtx attaches trace to ctx and returns the new context.
+func (t *http2Server) HandleStreams(handle func(*Stream), traceCtx func(context.Context, string) context.Context) {
 	// Check the validity of client preface.
 	preface := make([]byte, len(clientPreface))
 	if _, err := io.ReadFull(t.conn, preface); err != nil {
@@ -248,6 +351,7 @@ func (t *http2Server) HandleStreams(handle func(*Stream)) {
 		t.Close()
 		return
 	}
+	atomic.StoreUint32(&t.activity, 1)
 	sf, ok := frame.(*http2.SettingsFrame)
 	if !ok {
 		grpclog.Printf("transport: http2Server.HandleStreams saw invalid preface type %T from client", frame)
@@ -258,6 +362,7 @@ func (t *http2Server) HandleStreams(handle func(*Stream)) {
 
 	for {
 		frame, err := t.framer.readFrame()
+		atomic.StoreUint32(&t.activity, 1)
 		if err != nil {
 			if se, ok := err.(http2.StreamError); ok {
 				t.mu.Lock()
@@ -279,7 +384,7 @@ func (t *http2Server) HandleStreams(handle func(*Stream)) {
 		}
 		switch frame := frame.(type) {
 		case *http2.MetaHeadersFrame:
-			if t.operateHeaders(frame, handle) {
+			if t.operateHeaders(frame, handle, traceCtx) {
 				t.Close()
 				break
 			}
@@ -334,7 +439,7 @@ func (t *http2Server) updateWindow(s *Stream, n uint32) {
 }
 
 func (t *http2Server) handleData(f *http2.DataFrame) {
-	size := len(f.Data())
+	size := f.Header().Length
 	if err := t.fc.onData(uint32(size)); err != nil {
 		grpclog.Printf("transport: http2Server %v", err)
 		t.Close()
@@ -349,6 +454,11 @@ func (t *http2Server) handleData(f *http2.DataFrame) {
 		return
 	}
 	if size > 0 {
+		if f.Header().Flags.Has(http2.FlagDataPadded) {
+			if w := t.fc.onRead(uint32(size) - uint32(len(f.Data()))); w > 0 {
+				t.controlBuf.put(&windowUpdate{0, w})
+			}
+		}
 		s.mu.Lock()
 		if s.state == streamDone {
 			s.mu.Unlock()
@@ -364,13 +474,20 @@ func (t *http2Server) handleData(f *http2.DataFrame) {
 			t.controlBuf.put(&resetStream{s.id, http2.ErrCodeFlowControl})
 			return
 		}
+		if f.Header().Flags.Has(http2.FlagDataPadded) {
+			if w := s.fc.onRead(uint32(size) - uint32(len(f.Data()))); w > 0 {
+				t.controlBuf.put(&windowUpdate{s.id, w})
+			}
+		}
 		s.mu.Unlock()
 		// TODO(bradfitz, zhaoq): A copy is required here because there is no
 		// guarantee f.Data() is consumed before the arrival of next frame.
 		// Can this copy be eliminated?
-		data := make([]byte, size)
-		copy(data, f.Data())
-		s.write(recvMsg{data: data})
+		if len(f.Data()) > 0 {
+			data := make([]byte, len(f.Data()))
+			copy(data, f.Data())
+			s.write(recvMsg{data: data})
+		}
 	}
 	if f.Header().Flags.Has(http2.FlagDataEndStream) {
 		// Received the end of stream from the client.
@@ -404,10 +521,50 @@ func (t *http2Server) handleSettings(f *http2.SettingsFrame) {
 	t.controlBuf.put(&settings{ack: true, ss: ss})
 }
 
+const (
+	maxPingStrikes     = 2
+	defaultPingTimeout = 2 * time.Hour
+)
+
 func (t *http2Server) handlePing(f *http2.PingFrame) {
+	if f.IsAck() { // Do nothing.
+		return
+	}
 	pingAck := &ping{ack: true}
 	copy(pingAck.data[:], f.Data[:])
 	t.controlBuf.put(pingAck)
+
+	now := time.Now()
+	defer func() {
+		t.lastPingAt = now
+	}()
+	// A reset ping strikes means that we don't need to check for policy
+	// violation for this ping and the pingStrikes counter should be set
+	// to 0.
+	if atomic.CompareAndSwapUint32(&t.resetPingStrikes, 1, 0) {
+		t.pingStrikes = 0
+		return
+	}
+	t.mu.Lock()
+	ns := len(t.activeStreams)
+	t.mu.Unlock()
+	if ns < 1 && !t.kep.PermitWithoutStream {
+		// Keepalive shouldn't be active thus, this new ping should
+		// have come after atleast defaultPingTimeout.
+		if t.lastPingAt.Add(defaultPingTimeout).After(now) {
+			t.pingStrikes++
+		}
+	} else {
+		// Check if keepalive policy is respected.
+		if t.lastPingAt.Add(t.kep.MinTime).After(now) {
+			t.pingStrikes++
+		}
+	}
+
+	if t.pingStrikes > maxPingStrikes {
+		// Send goaway and close the connection.
+		t.controlBuf.put(&goAway{code: http2.ErrCodeEnhanceYourCalm, debugData: []byte("too_many_pings")})
+	}
 }
 
 func (t *http2Server) handleWindowUpdate(f *http2.WindowUpdateFrame) {
@@ -426,6 +583,13 @@ func (t *http2Server) writeHeaders(s *Stream, b *bytes.Buffer, endStream bool) e
 	first := true
 	endHeaders := false
 	var err error
+	defer func() {
+		if err == nil {
+			// Reset ping strikes when seding headers since that might cause the
+			// peer to send ping.
+			atomic.StoreUint32(&t.resetPingStrikes, 1)
+		}
+	}()
 	// Sends the headers in a single batch.
 	for !endHeaders {
 		size := t.hBuf.Len()
@@ -462,6 +626,14 @@ func (t *http2Server) WriteHeader(s *Stream, md metadata.MD) error {
 		return ErrIllegalHeaderWrite
 	}
 	s.headerOk = true
+	if md.Len() > 0 {
+		if s.header.Len() > 0 {
+			s.header = metadata.Join(s.header, md)
+		} else {
+			s.header = md
+		}
+	}
+	md = s.header
 	s.mu.Unlock()
 	if _, err := wait(s.ctx, nil, nil, t.shutdownChan, t.writableChan); err != nil {
 		return err
@@ -481,9 +653,16 @@ func (t *http2Server) WriteHeader(s *Stream, md metadata.MD) error {
 			t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: entry})
 		}
 	}
+	bufLen := t.hBuf.Len()
 	if err := t.writeHeaders(s, t.hBuf, false); err != nil {
 		return err
 	}
+	if t.stats != nil {
+		outHeader := &stats.OutHeader{
+			WireLength: bufLen,
+		}
+		t.stats.HandleRPC(s.Context(), outHeader)
+	}
 	t.writableChan <- 0
 	return nil
 }
@@ -492,8 +671,8 @@ func (t *http2Server) WriteHeader(s *Stream, md metadata.MD) error {
 // There is no further I/O operations being able to perform on this stream.
 // TODO(zhaoq): Now it indicates the end of entire stream. Revisit if early
 // OK is adopted.
-func (t *http2Server) WriteStatus(s *Stream, statusCode codes.Code, statusDesc string) error {
-	var headersSent bool
+func (t *http2Server) WriteStatus(s *Stream, st *status.Status) error {
+	var headersSent, hasHeader bool
 	s.mu.Lock()
 	if s.state == streamDone {
 		s.mu.Unlock()
@@ -502,7 +681,16 @@ func (t *http2Server) WriteStatus(s *Stream, statusCode codes.Code, statusDesc s
 	if s.headerOk {
 		headersSent = true
 	}
+	if s.header.Len() > 0 {
+		hasHeader = true
+	}
 	s.mu.Unlock()
+
+	if !headersSent && hasHeader {
+		t.WriteHeader(s, nil)
+		headersSent = true
+	}
+
 	if _, err := wait(s.ctx, nil, nil, t.shutdownChan, t.writableChan); err != nil {
 		return err
 	}
@@ -514,9 +702,24 @@ func (t *http2Server) WriteStatus(s *Stream, statusCode codes.Code, statusDesc s
 	t.hEnc.WriteField(
 		hpack.HeaderField{
 			Name:  "grpc-status",
-			Value: strconv.Itoa(int(statusCode)),
+			Value: strconv.Itoa(int(st.Code())),
 		})
-	t.hEnc.WriteField(hpack.HeaderField{Name: "grpc-message", Value: encodeGrpcMessage(statusDesc)})
+	t.hEnc.WriteField(hpack.HeaderField{Name: "grpc-message", Value: encodeGrpcMessage(st.Message())})
+
+	if p := st.Proto(); p != nil && len(p.Details) > 0 {
+		stBytes, err := proto.Marshal(p)
+		if err != nil {
+			// TODO: return error instead, when callers are able to handle it.
+			panic(err)
+		}
+
+		for k, v := range metadata.New(map[string]string{"grpc-status-details-bin": (string)(stBytes)}) {
+			for _, entry := range v {
+				t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: entry})
+			}
+		}
+	}
+
 	// Attach the trailer metadata.
 	for k, v := range s.trailer {
 		// Clients don't tolerate reading restricted headers after some non restricted ones were sent.
@@ -527,10 +730,17 @@ func (t *http2Server) WriteStatus(s *Stream, statusCode codes.Code, statusDesc s
 			t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: entry})
 		}
 	}
+	bufLen := t.hBuf.Len()
 	if err := t.writeHeaders(s, t.hBuf, true); err != nil {
 		t.Close()
 		return err
 	}
+	if t.stats != nil {
+		outTrailer := &stats.OutTrailer{
+			WireLength: bufLen,
+		}
+		t.stats.HandleRPC(s.Context(), outTrailer)
+	}
 	t.closeStream(s)
 	t.writableChan <- 0
 	return nil
@@ -538,7 +748,7 @@ func (t *http2Server) WriteStatus(s *Stream, statusCode codes.Code, statusDesc s
 
 // Write converts the data into HTTP2 data frame and sends it out. Non-nil error
 // is returns if it fails (e.g., framing error, transport error).
-func (t *http2Server) Write(s *Stream, data []byte, opts *Options) error {
+func (t *http2Server) Write(s *Stream, data []byte, opts *Options) (err error) {
 	// TODO(zhaoq): Support multi-writers for a single stream.
 	var writeHeaderFrame bool
 	s.mu.Lock()
@@ -548,49 +758,32 @@ func (t *http2Server) Write(s *Stream, data []byte, opts *Options) error {
 	}
 	if !s.headerOk {
 		writeHeaderFrame = true
-		s.headerOk = true
 	}
 	s.mu.Unlock()
 	if writeHeaderFrame {
-		if _, err := wait(s.ctx, nil, nil, t.shutdownChan, t.writableChan); err != nil {
-			return err
-		}
-		t.hBuf.Reset()
-		t.hEnc.WriteField(hpack.HeaderField{Name: ":status", Value: "200"})
-		t.hEnc.WriteField(hpack.HeaderField{Name: "content-type", Value: "application/grpc"})
-		if s.sendCompress != "" {
-			t.hEnc.WriteField(hpack.HeaderField{Name: "grpc-encoding", Value: s.sendCompress})
-		}
-		p := http2.HeadersFrameParam{
-			StreamID:      s.id,
-			BlockFragment: t.hBuf.Bytes(),
-			EndHeaders:    true,
-		}
-		if err := t.framer.writeHeaders(false, p); err != nil {
-			t.Close()
-			return connectionErrorf(true, err, "transport: %v", err)
-		}
-		t.writableChan <- 0
+		t.WriteHeader(s, nil)
 	}
+	defer func() {
+		if err == nil {
+			// Reset ping strikes when sending data since this might cause
+			// the peer to send ping.
+			atomic.StoreUint32(&t.resetPingStrikes, 1)
+		}
+	}()
 	r := bytes.NewBuffer(data)
 	for {
 		if r.Len() == 0 {
 			return nil
 		}
 		size := http2MaxFrameLen
-		s.sendQuotaPool.add(0)
 		// Wait until the stream has some quota to send the data.
 		sq, err := wait(s.ctx, nil, nil, t.shutdownChan, s.sendQuotaPool.acquire())
 		if err != nil {
 			return err
 		}
-		t.sendQuotaPool.add(0)
 		// Wait until the transport has some quota to send the data.
 		tq, err := wait(s.ctx, nil, nil, t.shutdownChan, t.sendQuotaPool.acquire())
 		if err != nil {
-			if _, ok := err.(StreamError); ok {
-				t.sendQuotaPool.cancel()
-			}
 			return err
 		}
 		if sq < size {
@@ -658,7 +851,7 @@ func (t *http2Server) applySettings(ss []http2.Setting) {
 			t.mu.Lock()
 			defer t.mu.Unlock()
 			for _, stream := range t.activeStreams {
-				stream.sendQuotaPool.reset(int(s.Val - t.streamSendQuota))
+				stream.sendQuotaPool.add(int(s.Val - t.streamSendQuota))
 			}
 			t.streamSendQuota = s.Val
 		}
@@ -666,6 +859,91 @@ func (t *http2Server) applySettings(ss []http2.Setting) {
 	}
 }
 
+// keepalive running in a separate goroutine does the following:
+// 1. Gracefully closes an idle connection after a duration of keepalive.MaxConnectionIdle.
+// 2. Gracefully closes any connection after a duration of keepalive.MaxConnectionAge.
+// 3. Forcibly closes a connection after an additive period of keepalive.MaxConnectionAgeGrace over keepalive.MaxConnectionAge.
+// 4. Makes sure a connection is alive by sending pings with a frequency of keepalive.Time and closes a non-resposive connection
+// after an additional duration of keepalive.Timeout.
+func (t *http2Server) keepalive() {
+	p := &ping{}
+	var pingSent bool
+	maxIdle := time.NewTimer(t.kp.MaxConnectionIdle)
+	maxAge := time.NewTimer(t.kp.MaxConnectionAge)
+	keepalive := time.NewTimer(t.kp.Time)
+	// NOTE: All exit paths of this function should reset their
+	// respecitve timers. A failure to do so will cause the
+	// following clean-up to deadlock and eventually leak.
+	defer func() {
+		if !maxIdle.Stop() {
+			<-maxIdle.C
+		}
+		if !maxAge.Stop() {
+			<-maxAge.C
+		}
+		if !keepalive.Stop() {
+			<-keepalive.C
+		}
+	}()
+	for {
+		select {
+		case <-maxIdle.C:
+			t.mu.Lock()
+			idle := t.idle
+			if idle.IsZero() { // The connection is non-idle.
+				t.mu.Unlock()
+				maxIdle.Reset(t.kp.MaxConnectionIdle)
+				continue
+			}
+			val := t.kp.MaxConnectionIdle - time.Since(idle)
+			if val <= 0 {
+				// The connection has been idle for a duration of keepalive.MaxConnectionIdle or more.
+				// Gracefully close the connection.
+				t.state = draining
+				t.mu.Unlock()
+				t.Drain()
+				// Reseting the timer so that the clean-up doesn't deadlock.
+				maxIdle.Reset(infinity)
+				return
+			}
+			t.mu.Unlock()
+			maxIdle.Reset(val)
+		case <-maxAge.C:
+			t.mu.Lock()
+			t.state = draining
+			t.mu.Unlock()
+			t.Drain()
+			maxAge.Reset(t.kp.MaxConnectionAgeGrace)
+			select {
+			case <-maxAge.C:
+				// Close the connection after grace period.
+				t.Close()
+				// Reseting the timer so that the clean-up doesn't deadlock.
+				maxAge.Reset(infinity)
+			case <-t.shutdownChan:
+			}
+			return
+		case <-keepalive.C:
+			if atomic.CompareAndSwapUint32(&t.activity, 1, 0) {
+				pingSent = false
+				keepalive.Reset(t.kp.Time)
+				continue
+			}
+			if pingSent {
+				t.Close()
+				// Reseting the timer so that the clean-up doesn't deadlock.
+				keepalive.Reset(infinity)
+				return
+			}
+			pingSent = true
+			t.controlBuf.put(p)
+			keepalive.Reset(t.kp.Timeout)
+		case <-t.shutdownChan:
+			return
+		}
+	}
+}
+
 // controller running in a separate goroutine takes charge of sending control
 // frames (e.g., window update, reset stream, setting, etc.) to the server.
 func (t *http2Server) controller() {
@@ -697,7 +975,10 @@ func (t *http2Server) controller() {
 					sid := t.maxStreamID
 					t.state = draining
 					t.mu.Unlock()
-					t.framer.writeGoAway(true, sid, http2.ErrCodeNo, nil)
+					t.framer.writeGoAway(true, sid, i.code, i.debugData)
+					if i.code == http2.ErrCodeEnhanceYourCalm {
+						t.Close()
+					}
 				case *flushIO:
 					t.framer.flushWrite()
 				case *ping:
@@ -735,6 +1016,10 @@ func (t *http2Server) Close() (err error) {
 	for _, s := range streams {
 		s.cancel()
 	}
+	if t.stats != nil {
+		connEnd := &stats.ConnEnd{}
+		t.stats.HandleConn(t.ctx, connEnd)
+	}
 	return
 }
 
@@ -743,6 +1028,9 @@ func (t *http2Server) Close() (err error) {
 func (t *http2Server) closeStream(s *Stream) {
 	t.mu.Lock()
 	delete(t.activeStreams, s.id)
+	if len(t.activeStreams) == 0 {
+		t.idle = time.Now()
+	}
 	if t.state == draining && len(t.activeStreams) == 0 {
 		defer t.Close()
 	}
@@ -766,9 +1054,21 @@ func (t *http2Server) closeStream(s *Stream) {
 }
 
 func (t *http2Server) RemoteAddr() net.Addr {
-	return t.conn.RemoteAddr()
+	return t.remoteAddr
 }
 
 func (t *http2Server) Drain() {
-	t.controlBuf.put(&goAway{})
+	t.controlBuf.put(&goAway{code: http2.ErrCodeNo})
+}
+
+var rgen = rand.New(rand.NewSource(time.Now().UnixNano()))
+
+func getJitter(v time.Duration) time.Duration {
+	if v == infinity {
+		return 0
+	}
+	// Generate a jitter between +/- 10% of the value.
+	r := int64(v / 10)
+	j := rgen.Int63n(2*r) - r
+	return time.Duration(j)
 }