forgejo-federation/vendor/go.mongodb.org/mongo-driver/bson/bsonrw/writer.go
2020-09-01 10:01:23 -04:00

102 lines
3 KiB
Go
Vendored

// Copyright (C) MongoDB, Inc. 2017-present.
//
// 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
package bsonrw
import (
"go.mongodb.org/mongo-driver/bson/bsontype"
"go.mongodb.org/mongo-driver/bson/primitive"
)
// ArrayWriter is the interface used to create a BSON or BSON adjacent array.
// Callers must ensure they call WriteArrayEnd when they have finished creating
// the array.
type ArrayWriter interface {
WriteArrayElement() (ValueWriter, error)
WriteArrayEnd() error
}
// DocumentWriter is the interface used to create a BSON or BSON adjacent
// document. Callers must ensure they call WriteDocumentEnd when they have
// finished creating the document.
type DocumentWriter interface {
WriteDocumentElement(string) (ValueWriter, error)
WriteDocumentEnd() error
}
// ValueWriter is the interface used to write BSON values. Implementations of
// this interface handle creating BSON or BSON adjacent representations of the
// values.
type ValueWriter interface {
WriteArray() (ArrayWriter, error)
WriteBinary(b []byte) error
WriteBinaryWithSubtype(b []byte, btype byte) error
WriteBoolean(bool) error
WriteCodeWithScope(code string) (DocumentWriter, error)
WriteDBPointer(ns string, oid primitive.ObjectID) error
WriteDateTime(dt int64) error
WriteDecimal128(primitive.Decimal128) error
WriteDouble(float64) error
WriteInt32(int32) error
WriteInt64(int64) error
WriteJavascript(code string) error
WriteMaxKey() error
WriteMinKey() error
WriteNull() error
WriteObjectID(primitive.ObjectID) error
WriteRegex(pattern, options string) error
WriteString(string) error
WriteDocument() (DocumentWriter, error)
WriteSymbol(symbol string) error
WriteTimestamp(t, i uint32) error
WriteUndefined() error
}
// ValueWriterFlusher is a superset of ValueWriter that exposes functionality to flush to the underlying buffer.
type ValueWriterFlusher interface {
ValueWriter
Flush() error
}
// BytesWriter is the interface used to write BSON bytes to a ValueWriter.
// This interface is meant to be a superset of ValueWriter, so that types that
// implement ValueWriter may also implement this interface.
type BytesWriter interface {
WriteValueBytes(t bsontype.Type, b []byte) error
}
// SliceWriter allows a pointer to a slice of bytes to be used as an io.Writer.
type SliceWriter []byte
func (sw *SliceWriter) Write(p []byte) (int, error) {
written := len(p)
*sw = append(*sw, p...)
return written, nil
}
type writer []byte
func (w *writer) Write(p []byte) (int, error) {
index := len(*w)
return w.WriteAt(p, int64(index))
}
func (w *writer) WriteAt(p []byte, off int64) (int, error) {
newend := off + int64(len(p))
if newend < int64(len(*w)) {
newend = int64(len(*w))
}
if newend > int64(cap(*w)) {
buf := make([]byte, int64(2*cap(*w))+newend)
copy(buf, *w)
*w = buf
}
*w = []byte(*w)[:newend]
copy([]byte(*w)[off:], p)
return len(p), nil
}