forgejo-federation/vendor/github.com/blevesearch/zap/v15/enumerator.go
6543 12a1f914f4
Vendor Update Go Libs (#13166)
* update github.com/alecthomas/chroma v0.8.0 -> v0.8.1

* github.com/blevesearch/bleve v1.0.10 -> v1.0.12

* editorconfig-core-go v2.1.1 -> v2.3.7

* github.com/gliderlabs/ssh v0.2.2 -> v0.3.1

* migrate editorconfig.ParseBytes to Parse

* github.com/shurcooL/vfsgen to 0d455de96546

* github.com/go-git/go-git/v5 v5.1.0 -> v5.2.0

* github.com/google/uuid v1.1.1 -> v1.1.2

* github.com/huandu/xstrings v1.3.0 -> v1.3.2

* github.com/klauspost/compress v1.10.11 -> v1.11.1

* github.com/markbates/goth v1.61.2 -> v1.65.0

* github.com/mattn/go-sqlite3 v1.14.0 -> v1.14.4

* github.com/mholt/archiver v3.3.0 -> v3.3.2

* github.com/microcosm-cc/bluemonday 4f7140c49acb -> v1.0.4

* github.com/minio/minio-go v7.0.4 -> v7.0.5

* github.com/olivere/elastic v7.0.9 -> v7.0.20

* github.com/urfave/cli v1.20.0 -> v1.22.4

* github.com/prometheus/client_golang v1.1.0 -> v1.8.0

* github.com/xanzy/go-gitlab v0.37.0 -> v0.38.1

* mvdan.cc/xurls v2.1.0 -> v2.2.0

Co-authored-by: Lauris BH <lauris@nix.lv>
2020-10-16 01:06:27 -04:00

138 lines
3.8 KiB
Go
Vendored

// Copyright (c) 2018 Couchbase, 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.
package zap
import (
"bytes"
"github.com/couchbase/vellum"
)
// enumerator provides an ordered traversal of multiple vellum
// iterators. Like JOIN of iterators, the enumerator produces a
// sequence of (key, iteratorIndex, value) tuples, sorted by key ASC,
// then iteratorIndex ASC, where the same key might be seen or
// repeated across multiple child iterators.
type enumerator struct {
itrs []vellum.Iterator
currKs [][]byte
currVs []uint64
lowK []byte
lowIdxs []int
lowCurr int
}
// newEnumerator returns a new enumerator over the vellum Iterators
func newEnumerator(itrs []vellum.Iterator) (*enumerator, error) {
rv := &enumerator{
itrs: itrs,
currKs: make([][]byte, len(itrs)),
currVs: make([]uint64, len(itrs)),
lowIdxs: make([]int, 0, len(itrs)),
}
for i, itr := range rv.itrs {
rv.currKs[i], rv.currVs[i] = itr.Current()
}
rv.updateMatches(false)
if rv.lowK == nil && len(rv.lowIdxs) == 0 {
return rv, vellum.ErrIteratorDone
}
return rv, nil
}
// updateMatches maintains the low key matches based on the currKs
func (m *enumerator) updateMatches(skipEmptyKey bool) {
m.lowK = nil
m.lowIdxs = m.lowIdxs[:0]
m.lowCurr = 0
for i, key := range m.currKs {
if (key == nil && m.currVs[i] == 0) || // in case of empty iterator
(len(key) == 0 && skipEmptyKey) { // skip empty keys
continue
}
cmp := bytes.Compare(key, m.lowK)
if cmp < 0 || len(m.lowIdxs) == 0 {
// reached a new low
m.lowK = key
m.lowIdxs = m.lowIdxs[:0]
m.lowIdxs = append(m.lowIdxs, i)
} else if cmp == 0 {
m.lowIdxs = append(m.lowIdxs, i)
}
}
}
// Current returns the enumerator's current key, iterator-index, and
// value. If the enumerator is not pointing at a valid value (because
// Next returned an error previously), Current will return nil,0,0.
func (m *enumerator) Current() ([]byte, int, uint64) {
var i int
var v uint64
if m.lowCurr < len(m.lowIdxs) {
i = m.lowIdxs[m.lowCurr]
v = m.currVs[i]
}
return m.lowK, i, v
}
// GetLowIdxsAndValues will return all of the iterator indices
// which point to the current key, and their corresponding
// values. This can be used by advanced caller which may need
// to peek into these other sets of data before processing.
func (m *enumerator) GetLowIdxsAndValues() ([]int, []uint64) {
values := make([]uint64, 0, len(m.lowIdxs))
for _, idx := range m.lowIdxs {
values = append(values, m.currVs[idx])
}
return m.lowIdxs, values
}
// Next advances the enumerator to the next key/iterator/value result,
// else vellum.ErrIteratorDone is returned.
func (m *enumerator) Next() error {
m.lowCurr += 1
if m.lowCurr >= len(m.lowIdxs) {
// move all the current low iterators forwards
for _, vi := range m.lowIdxs {
err := m.itrs[vi].Next()
if err != nil && err != vellum.ErrIteratorDone {
return err
}
m.currKs[vi], m.currVs[vi] = m.itrs[vi].Current()
}
// can skip any empty keys encountered at this point
m.updateMatches(true)
}
if m.lowK == nil && len(m.lowIdxs) == 0 {
return vellum.ErrIteratorDone
}
return nil
}
// Close all the underlying Iterators. The first error, if any, will
// be returned.
func (m *enumerator) Close() error {
var rv error
for _, itr := range m.itrs {
err := itr.Close()
if rv == nil {
rv = err
}
}
return rv
}