service/vendor/github.com/goccy/go-json/internal/encoder/compact.go

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2023-12-21 22:17:40 +08:00
package encoder
import (
"bytes"
"fmt"
"strconv"
"unsafe"
"github.com/goccy/go-json/internal/errors"
)
var (
isWhiteSpace = [256]bool{
' ': true,
'\n': true,
'\t': true,
'\r': true,
}
isHTMLEscapeChar = [256]bool{
'<': true,
'>': true,
'&': true,
}
nul = byte('\000')
)
func Compact(buf *bytes.Buffer, src []byte, escape bool) error {
if len(src) == 0 {
return errors.ErrUnexpectedEndOfJSON("", 0)
}
buf.Grow(len(src))
dst := buf.Bytes()
ctx := TakeRuntimeContext()
ctxBuf := ctx.Buf[:0]
ctxBuf = append(append(ctxBuf, src...), nul)
ctx.Buf = ctxBuf
if err := compactAndWrite(buf, dst, ctxBuf, escape); err != nil {
ReleaseRuntimeContext(ctx)
return err
}
ReleaseRuntimeContext(ctx)
return nil
}
func compactAndWrite(buf *bytes.Buffer, dst []byte, src []byte, escape bool) error {
dst, err := compact(dst, src, escape)
if err != nil {
return err
}
if _, err := buf.Write(dst); err != nil {
return err
}
return nil
}
func compact(dst, src []byte, escape bool) ([]byte, error) {
buf, cursor, err := compactValue(dst, src, 0, escape)
if err != nil {
return nil, err
}
if err := validateEndBuf(src, cursor); err != nil {
return nil, err
}
return buf, nil
}
func validateEndBuf(src []byte, cursor int64) error {
for {
switch src[cursor] {
case ' ', '\t', '\n', '\r':
cursor++
continue
case nul:
return nil
}
return errors.ErrSyntax(
fmt.Sprintf("invalid character '%c' after top-level value", src[cursor]),
cursor+1,
)
}
}
func skipWhiteSpace(buf []byte, cursor int64) int64 {
LOOP:
if isWhiteSpace[buf[cursor]] {
cursor++
goto LOOP
}
return cursor
}
func compactValue(dst, src []byte, cursor int64, escape bool) ([]byte, int64, error) {
for {
switch src[cursor] {
case ' ', '\t', '\n', '\r':
cursor++
continue
case '{':
return compactObject(dst, src, cursor, escape)
case '}':
return nil, 0, errors.ErrSyntax("unexpected character '}'", cursor)
case '[':
return compactArray(dst, src, cursor, escape)
case ']':
return nil, 0, errors.ErrSyntax("unexpected character ']'", cursor)
case '"':
return compactString(dst, src, cursor, escape)
case '-', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9':
return compactNumber(dst, src, cursor)
case 't':
return compactTrue(dst, src, cursor)
case 'f':
return compactFalse(dst, src, cursor)
case 'n':
return compactNull(dst, src, cursor)
default:
return nil, 0, errors.ErrSyntax(fmt.Sprintf("unexpected character '%c'", src[cursor]), cursor)
}
}
}
func compactObject(dst, src []byte, cursor int64, escape bool) ([]byte, int64, error) {
if src[cursor] == '{' {
dst = append(dst, '{')
} else {
return nil, 0, errors.ErrExpected("expected { character for object value", cursor)
}
cursor = skipWhiteSpace(src, cursor+1)
if src[cursor] == '}' {
dst = append(dst, '}')
return dst, cursor + 1, nil
}
var err error
for {
cursor = skipWhiteSpace(src, cursor)
dst, cursor, err = compactString(dst, src, cursor, escape)
if err != nil {
return nil, 0, err
}
cursor = skipWhiteSpace(src, cursor)
if src[cursor] != ':' {
return nil, 0, errors.ErrExpected("colon after object key", cursor)
}
dst = append(dst, ':')
dst, cursor, err = compactValue(dst, src, cursor+1, escape)
if err != nil {
return nil, 0, err
}
cursor = skipWhiteSpace(src, cursor)
switch src[cursor] {
case '}':
dst = append(dst, '}')
cursor++
return dst, cursor, nil
case ',':
dst = append(dst, ',')
default:
return nil, 0, errors.ErrExpected("comma after object value", cursor)
}
cursor++
}
}
func compactArray(dst, src []byte, cursor int64, escape bool) ([]byte, int64, error) {
if src[cursor] == '[' {
dst = append(dst, '[')
} else {
return nil, 0, errors.ErrExpected("expected [ character for array value", cursor)
}
cursor = skipWhiteSpace(src, cursor+1)
if src[cursor] == ']' {
dst = append(dst, ']')
return dst, cursor + 1, nil
}
var err error
for {
dst, cursor, err = compactValue(dst, src, cursor, escape)
if err != nil {
return nil, 0, err
}
cursor = skipWhiteSpace(src, cursor)
switch src[cursor] {
case ']':
dst = append(dst, ']')
cursor++
return dst, cursor, nil
case ',':
dst = append(dst, ',')
default:
return nil, 0, errors.ErrExpected("comma after array value", cursor)
}
cursor++
}
}
func compactString(dst, src []byte, cursor int64, escape bool) ([]byte, int64, error) {
if src[cursor] != '"' {
return nil, 0, errors.ErrInvalidCharacter(src[cursor], "string", cursor)
}
start := cursor
for {
cursor++
c := src[cursor]
if escape {
if isHTMLEscapeChar[c] {
dst = append(dst, src[start:cursor]...)
dst = append(dst, `\u00`...)
dst = append(dst, hex[c>>4], hex[c&0xF])
start = cursor + 1
} else if c == 0xE2 && cursor+2 < int64(len(src)) && src[cursor+1] == 0x80 && src[cursor+2]&^1 == 0xA8 {
dst = append(dst, src[start:cursor]...)
dst = append(dst, `\u202`...)
dst = append(dst, hex[src[cursor+2]&0xF])
cursor += 2
start = cursor + 3
}
}
switch c {
case '\\':
cursor++
if src[cursor] == nul {
return nil, 0, errors.ErrUnexpectedEndOfJSON("string", int64(len(src)))
}
case '"':
cursor++
return append(dst, src[start:cursor]...), cursor, nil
case nul:
return nil, 0, errors.ErrUnexpectedEndOfJSON("string", int64(len(src)))
}
}
}
func compactNumber(dst, src []byte, cursor int64) ([]byte, int64, error) {
start := cursor
for {
cursor++
if floatTable[src[cursor]] {
continue
}
break
}
num := src[start:cursor]
if _, err := strconv.ParseFloat(*(*string)(unsafe.Pointer(&num)), 64); err != nil {
return nil, 0, err
}
dst = append(dst, num...)
return dst, cursor, nil
}
func compactTrue(dst, src []byte, cursor int64) ([]byte, int64, error) {
if cursor+3 >= int64(len(src)) {
return nil, 0, errors.ErrUnexpectedEndOfJSON("true", cursor)
}
if !bytes.Equal(src[cursor:cursor+4], []byte(`true`)) {
return nil, 0, errors.ErrInvalidCharacter(src[cursor], "true", cursor)
}
dst = append(dst, "true"...)
cursor += 4
return dst, cursor, nil
}
func compactFalse(dst, src []byte, cursor int64) ([]byte, int64, error) {
if cursor+4 >= int64(len(src)) {
return nil, 0, errors.ErrUnexpectedEndOfJSON("false", cursor)
}
if !bytes.Equal(src[cursor:cursor+5], []byte(`false`)) {
return nil, 0, errors.ErrInvalidCharacter(src[cursor], "false", cursor)
}
dst = append(dst, "false"...)
cursor += 5
return dst, cursor, nil
}
func compactNull(dst, src []byte, cursor int64) ([]byte, int64, error) {
if cursor+3 >= int64(len(src)) {
return nil, 0, errors.ErrUnexpectedEndOfJSON("null", cursor)
}
if !bytes.Equal(src[cursor:cursor+4], []byte(`null`)) {
return nil, 0, errors.ErrInvalidCharacter(src[cursor], "null", cursor)
}
dst = append(dst, "null"...)
cursor += 4
return dst, cursor, nil
}