traefik/vendor/github.com/mailru/easyjson/jwriter/writer.go
2017-03-09 13:13:02 +01:00

297 lines
7.4 KiB
Go

// Package jwriter contains a JSON writer.
package jwriter
import (
"encoding/base64"
"io"
"strconv"
"unicode/utf8"
"github.com/mailru/easyjson/buffer"
)
// Flags describe various encoding options. The behavior may be actually implemented in the encoder, but
// Flags field in Writer is used to set and pass them around.
type Flags int
const (
NilMapAsEmpty Flags = 1 << iota // Encode nil map as '{}' rather than 'null'.
NilSliceAsEmpty // Encode nil slice as '[]' rather than 'null'.
)
// Writer is a JSON writer.
type Writer struct {
Flags Flags
Error error
Buffer buffer.Buffer
}
// Size returns the size of the data that was written out.
func (w *Writer) Size() int {
return w.Buffer.Size()
}
// DumpTo outputs the data to given io.Writer, resetting the buffer.
func (w *Writer) DumpTo(out io.Writer) (written int, err error) {
return w.Buffer.DumpTo(out)
}
// BuildBytes returns writer data as a single byte slice.
func (w *Writer) BuildBytes() ([]byte, error) {
if w.Error != nil {
return nil, w.Error
}
return w.Buffer.BuildBytes(), nil
}
// RawByte appends raw binary data to the buffer.
func (w *Writer) RawByte(c byte) {
w.Buffer.AppendByte(c)
}
// RawByte appends raw binary data to the buffer.
func (w *Writer) RawString(s string) {
w.Buffer.AppendString(s)
}
// RawByte appends raw binary data to the buffer or sets the error if it is given. Useful for
// calling with results of MarshalJSON-like functions.
func (w *Writer) Raw(data []byte, err error) {
switch {
case w.Error != nil:
return
case err != nil:
w.Error = err
case len(data) > 0:
w.Buffer.AppendBytes(data)
default:
w.RawString("null")
}
}
// Base64Bytes appends data to the buffer after base64 encoding it
func (w *Writer) Base64Bytes(data []byte) {
if data == nil {
w.Buffer.AppendString("null")
return
}
w.Buffer.AppendByte('"')
dst := make([]byte, base64.StdEncoding.EncodedLen(len(data)))
base64.StdEncoding.Encode(dst, data)
w.Buffer.AppendBytes(dst)
w.Buffer.AppendByte('"')
}
func (w *Writer) Uint8(n uint8) {
w.Buffer.EnsureSpace(3)
w.Buffer.Buf = strconv.AppendUint(w.Buffer.Buf, uint64(n), 10)
}
func (w *Writer) Uint16(n uint16) {
w.Buffer.EnsureSpace(5)
w.Buffer.Buf = strconv.AppendUint(w.Buffer.Buf, uint64(n), 10)
}
func (w *Writer) Uint32(n uint32) {
w.Buffer.EnsureSpace(10)
w.Buffer.Buf = strconv.AppendUint(w.Buffer.Buf, uint64(n), 10)
}
func (w *Writer) Uint(n uint) {
w.Buffer.EnsureSpace(20)
w.Buffer.Buf = strconv.AppendUint(w.Buffer.Buf, uint64(n), 10)
}
func (w *Writer) Uint64(n uint64) {
w.Buffer.EnsureSpace(20)
w.Buffer.Buf = strconv.AppendUint(w.Buffer.Buf, n, 10)
}
func (w *Writer) Int8(n int8) {
w.Buffer.EnsureSpace(4)
w.Buffer.Buf = strconv.AppendInt(w.Buffer.Buf, int64(n), 10)
}
func (w *Writer) Int16(n int16) {
w.Buffer.EnsureSpace(6)
w.Buffer.Buf = strconv.AppendInt(w.Buffer.Buf, int64(n), 10)
}
func (w *Writer) Int32(n int32) {
w.Buffer.EnsureSpace(11)
w.Buffer.Buf = strconv.AppendInt(w.Buffer.Buf, int64(n), 10)
}
func (w *Writer) Int(n int) {
w.Buffer.EnsureSpace(21)
w.Buffer.Buf = strconv.AppendInt(w.Buffer.Buf, int64(n), 10)
}
func (w *Writer) Int64(n int64) {
w.Buffer.EnsureSpace(21)
w.Buffer.Buf = strconv.AppendInt(w.Buffer.Buf, n, 10)
}
func (w *Writer) Uint8Str(n uint8) {
w.Buffer.EnsureSpace(3)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
w.Buffer.Buf = strconv.AppendUint(w.Buffer.Buf, uint64(n), 10)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
}
func (w *Writer) Uint16Str(n uint16) {
w.Buffer.EnsureSpace(5)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
w.Buffer.Buf = strconv.AppendUint(w.Buffer.Buf, uint64(n), 10)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
}
func (w *Writer) Uint32Str(n uint32) {
w.Buffer.EnsureSpace(10)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
w.Buffer.Buf = strconv.AppendUint(w.Buffer.Buf, uint64(n), 10)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
}
func (w *Writer) UintStr(n uint) {
w.Buffer.EnsureSpace(20)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
w.Buffer.Buf = strconv.AppendUint(w.Buffer.Buf, uint64(n), 10)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
}
func (w *Writer) Uint64Str(n uint64) {
w.Buffer.EnsureSpace(20)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
w.Buffer.Buf = strconv.AppendUint(w.Buffer.Buf, n, 10)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
}
func (w *Writer) Int8Str(n int8) {
w.Buffer.EnsureSpace(4)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
w.Buffer.Buf = strconv.AppendInt(w.Buffer.Buf, int64(n), 10)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
}
func (w *Writer) Int16Str(n int16) {
w.Buffer.EnsureSpace(6)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
w.Buffer.Buf = strconv.AppendInt(w.Buffer.Buf, int64(n), 10)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
}
func (w *Writer) Int32Str(n int32) {
w.Buffer.EnsureSpace(11)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
w.Buffer.Buf = strconv.AppendInt(w.Buffer.Buf, int64(n), 10)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
}
func (w *Writer) IntStr(n int) {
w.Buffer.EnsureSpace(21)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
w.Buffer.Buf = strconv.AppendInt(w.Buffer.Buf, int64(n), 10)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
}
func (w *Writer) Int64Str(n int64) {
w.Buffer.EnsureSpace(21)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
w.Buffer.Buf = strconv.AppendInt(w.Buffer.Buf, n, 10)
w.Buffer.Buf = append(w.Buffer.Buf, '"')
}
func (w *Writer) Float32(n float32) {
w.Buffer.EnsureSpace(20)
w.Buffer.Buf = strconv.AppendFloat(w.Buffer.Buf, float64(n), 'g', -1, 32)
}
func (w *Writer) Float64(n float64) {
w.Buffer.EnsureSpace(20)
w.Buffer.Buf = strconv.AppendFloat(w.Buffer.Buf, n, 'g', -1, 64)
}
func (w *Writer) Bool(v bool) {
w.Buffer.EnsureSpace(5)
if v {
w.Buffer.Buf = append(w.Buffer.Buf, "true"...)
} else {
w.Buffer.Buf = append(w.Buffer.Buf, "false"...)
}
}
const chars = "0123456789abcdef"
func isNotEscapedSingleChar(c byte) bool {
// Note: might make sense to use a table if there are more chars to escape. With 4 chars
// it benchmarks the same.
return c != '<' && c != '\\' && c != '"' && c != '>' && c >= 0x20 && c < utf8.RuneSelf
}
func (w *Writer) String(s string) {
w.Buffer.AppendByte('"')
// Portions of the string that contain no escapes are appended as
// byte slices.
p := 0 // last non-escape symbol
for i := 0; i < len(s); {
c := s[i]
if isNotEscapedSingleChar(c) {
// single-width character, no escaping is required
i++
continue
} else if c < utf8.RuneSelf {
// single-with character, need to escape
w.Buffer.AppendString(s[p:i])
switch c {
case '\t':
w.Buffer.AppendString(`\t`)
case '\r':
w.Buffer.AppendString(`\r`)
case '\n':
w.Buffer.AppendString(`\n`)
case '\\':
w.Buffer.AppendString(`\\`)
case '"':
w.Buffer.AppendString(`\"`)
default:
w.Buffer.AppendString(`\u00`)
w.Buffer.AppendByte(chars[c>>4])
w.Buffer.AppendByte(chars[c&0xf])
}
i++
p = i
continue
}
// broken utf
runeValue, runeWidth := utf8.DecodeRuneInString(s[i:])
if runeValue == utf8.RuneError && runeWidth == 1 {
w.Buffer.AppendString(s[p:i])
w.Buffer.AppendString(`\ufffd`)
i++
p = i
continue
}
// jsonp stuff - tab separator and line separator
if runeValue == '\u2028' || runeValue == '\u2029' {
w.Buffer.AppendString(s[p:i])
w.Buffer.AppendString(`\u202`)
w.Buffer.AppendByte(chars[runeValue&0xf])
i += runeWidth
p = i
continue
}
i += runeWidth
}
w.Buffer.AppendString(s[p:])
w.Buffer.AppendByte('"')
}