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mirror of https://github.com/json-iterator/go.git synced 2025-06-15 22:50:24 +02:00

merge lexer with iterator

This commit is contained in:
Tao Wen
2016-12-01 10:35:38 +08:00
parent 6f134c8790
commit 5488b122cd
27 changed files with 466 additions and 8127 deletions

View File

@ -1,358 +1,294 @@
package jsoniter
import (
fflib "github.com/pquerna/ffjson/fflib/v1"
"strconv"
"io"
"fmt"
"unicode/utf16"
)
type Token fflib.FFTok
const TokenInteger = Token(fflib.FFTok_integer)
const TokenDouble = Token(fflib.FFTok_double)
const TokenBool = Token(fflib.FFTok_bool)
const TokenError = Token(fflib.FFTok_error)
const TokenLeftBrace = Token(fflib.FFTok_left_brace)
const TokenLeftBracket = Token(fflib.FFTok_left_bracket)
const TokenRightBrace = Token(fflib.FFTok_right_brace)
const TokenRightBracket = Token(fflib.FFTok_right_bracket)
const TokenComma = Token(fflib.FFTok_comma)
const TokenString = Token(fflib.FFTok_string)
const TokenColon = Token(fflib.FFTok_colon)
func (tok Token) ToString() string {
return fmt.Sprintf("%v", fflib.FFTok(tok))
}
type Iterator struct {
ErrorHandler func(error)
lexer *fflib.FFLexer
reader io.Reader
buf []byte
head int
tail int
Error error
}
type UnexpectedToken struct {
Expected Token
Actual Token
}
func (err *UnexpectedToken) Error() string {
return fmt.Sprintf("unexpected token, expected %v, actual %v", fflib.FFTok(err.Expected), fflib.FFTok(err.Actual))
}
func NewIterator(input []byte) Iterator {
lexer := fflib.NewFFLexer(input)
return Iterator{
lexer: lexer,
func Parse(reader io.Reader, bufSize int) *Iterator {
return &Iterator{
reader: reader,
buf: make([]byte, bufSize),
head: 0,
tail: 0,
}
}
func (iter Iterator) ReadArray(callback func(Iterator, int)) {
lexer := iter.lexer
if !iter.AssertToken(TokenLeftBrace) {
return
func ParseBytes(input []byte) *Iterator {
return &Iterator{
reader: nil,
buf: input,
head: 0,
tail: len(input),
}
index := 0
for {
lexer.Scan()
callback(iter, index)
index += 1
if iter.Token() != TokenComma {
break
}
func ParseString(input string) *Iterator {
return ParseBytes([]byte(input))
}
func (iter *Iterator) ReportError(operation string, msg string) {
iter.Error = fmt.Errorf("%s: %s, parsing %v at %s", operation, msg, iter.head, string(iter.buf[0:iter.tail]))
}
func (iter *Iterator) readByte() (ret byte) {
if iter.head == iter.tail {
if iter.reader == nil {
iter.Error = io.EOF
return
}
}
iter.AssertToken(TokenRightBrace)
lexer.Scan()
}
func (iter Iterator) ReadObject(callback func(Iterator, string)) {
lexer := iter.lexer
if !iter.AssertToken(TokenLeftBracket) {
return
}
for {
lexer.Scan()
field := iter.ReadString()
iter.AssertToken(TokenColon)
lexer.Scan()
callback(iter, field)
if iter.Token() != TokenComma {
break
n, err := iter.reader.Read(iter.buf)
if err != nil {
iter.Error = err
return
}
}
iter.AssertToken(TokenRightBracket)
lexer.Scan()
}
func (iter Iterator) Skip() {
switch iter.Token() {
case TokenLeftBracket:
iter.ReadObject(func(iter Iterator, field string) {
iter.Skip()
})
case TokenLeftBrace:
iter.ReadArray(func(iter Iterator, index int) {
iter.Skip()
})
default:
iter.lexer.Scan()
}
}
func (iter Iterator) ReadInt8() (rval int8) {
lexer := iter.lexer
if !iter.AssertToken(TokenInteger) {
return
}
field, err := lexer.CaptureField(lexer.Token)
if err != nil {
iter.OnError(err)
return
}
lexer.Scan()
number, err := strconv.ParseInt(string(field), 10, 8)
if err != nil {
iter.OnError(fmt.Errorf("failed to convert %v: %v", string(field), err.Error()))
return
}
return int8(number)
}
func (iter Iterator) ReadInt16() (rval int16) {
lexer := iter.lexer
if !iter.AssertToken(TokenInteger) {
return
}
field, err := lexer.CaptureField(lexer.Token)
if err != nil {
iter.OnError(err)
return
}
lexer.Scan()
number, err := strconv.ParseInt(string(field), 10, 16)
if err != nil {
iter.OnError(fmt.Errorf("failed to convert %v: %v", string(field), err.Error()))
return
}
return int16(number)
}
func (iter Iterator) ReadInt32() (rval int32) {
lexer := iter.lexer
if !iter.AssertToken(TokenInteger) {
return
}
field, err := lexer.CaptureField(lexer.Token)
if err != nil {
iter.OnError(err)
return
}
lexer.Scan()
number, err := strconv.ParseInt(string(field), 10, 32)
if err != nil {
iter.OnError(fmt.Errorf("failed to convert %v: %v", string(field), err.Error()))
return
}
return int32(number)
}
func (iter Iterator) ReadInt64() (rval int64) {
lexer := iter.lexer
if !iter.AssertToken(TokenInteger) {
return
}
field, err := lexer.CaptureField(lexer.Token)
if err != nil {
iter.OnError(err)
return
}
lexer.Scan()
number, err := strconv.ParseInt(string(field), 10, 64)
if err != nil {
iter.OnError(fmt.Errorf("failed to convert %v: %v", string(field), err.Error()))
return
}
return number
}
func (iter Iterator) ReadInt() (rval int) {
lexer := iter.lexer
n, err := lexer.LexInt64()
if err != nil {
iter.OnError(err)
return
}
return int(n)
}
func (iter Iterator) ReadUint() (rval uint) {
lexer := iter.lexer
if !iter.AssertToken(TokenInteger) {
return
}
field, err := lexer.CaptureField(lexer.Token)
if err != nil {
iter.OnError(err)
return
}
lexer.Scan()
number, err := strconv.ParseUint(string(field), 10, 64)
if err != nil {
iter.OnError(fmt.Errorf("failed to convert %v: %v", string(field), err.Error()))
return
}
return uint(number)
}
func (iter Iterator) ReadUint8() (rval uint8) {
lexer := iter.lexer
if !iter.AssertToken(TokenInteger) {
return
}
field, err := lexer.CaptureField(lexer.Token)
if err != nil {
iter.OnError(err)
return
}
lexer.Scan()
number, err := strconv.ParseUint(string(field), 10, 8)
if err != nil {
iter.OnError(fmt.Errorf("failed to convert %v: %v", string(field), err.Error()))
return
}
return uint8(number)
}
func (iter Iterator) ReadUint16() (rval uint16) {
lexer := iter.lexer
if !iter.AssertToken(TokenInteger) {
return
}
field, err := lexer.CaptureField(lexer.Token)
if err != nil {
iter.OnError(err)
return
}
lexer.Scan()
number, err := strconv.ParseUint(string(field), 10, 16)
if err != nil {
iter.OnError(fmt.Errorf("failed to convert %v: %v", string(field), err.Error()))
return
}
return uint16(number)
}
func (iter Iterator) ReadUint32() (rval uint32) {
lexer := iter.lexer
if !iter.AssertToken(TokenInteger) {
return
}
field, err := lexer.CaptureField(lexer.Token)
if err != nil {
iter.OnError(err)
return
}
lexer.Scan()
number, err := strconv.ParseUint(string(field), 10, 32)
if err != nil {
iter.OnError(fmt.Errorf("failed to convert %v: %v", string(field), err.Error()))
return
}
return uint32(number)
}
func (iter Iterator) ReadUint64() (rval uint64) {
lexer := iter.lexer
if !iter.AssertToken(TokenInteger) {
return
}
field, err := lexer.CaptureField(lexer.Token)
if err != nil {
iter.OnError(err)
return
}
lexer.Scan()
number, err := strconv.ParseUint(string(field), 10, 64)
if err != nil {
iter.OnError(fmt.Errorf("failed to convert %v: %v", string(field), err.Error()))
return
}
return uint64(number)
}
func (iter Iterator) ReadFloat32() (rval float32) {
lexer := iter.lexer
if !iter.AssertToken(TokenDouble) {
return
}
field, err := lexer.CaptureField(lexer.Token)
if err != nil {
iter.OnError(err)
return
}
lexer.Scan()
number, err := strconv.ParseFloat(string(field), 32)
if err != nil {
iter.OnError(fmt.Errorf("failed to convert %v: %v", string(field), err.Error()))
return
}
return float32(number)
}
func (iter Iterator) ReadFloat64() (rval float64) {
lexer := iter.lexer
if !iter.AssertToken(TokenDouble) {
return
}
field, err := lexer.CaptureField(lexer.Token)
if err != nil {
iter.OnError(err)
return
}
lexer.Scan()
number, err := strconv.ParseFloat(string(field), 64)
if err != nil {
iter.OnError(fmt.Errorf("failed to convert %v: %v", string(field), err.Error()))
return
}
return float64(number)
}
func (iter Iterator) ReadString() (rval string) {
lexer := iter.lexer
if !iter.AssertToken(TokenString) {
return
}
field, err := lexer.CaptureField(lexer.Token)
if err != nil {
iter.OnError(err)
return
}
lexer.Scan()
return string(field[1:len(field) - 1])
}
func (iter Iterator) AssertToken(expected Token) bool {
actual := iter.Token()
if expected != actual {
if actual == TokenError {
fmt.Println(iter.lexer.BigError.Error())
if n == 0 {
iter.Error = io.EOF
return
}
iter.OnError(&UnexpectedToken{
Expected: expected,
Actual: actual,
})
return false
iter.head = 0
iter.tail = n
}
return true
ret = iter.buf[iter.head]
iter.head += 1
return ret
}
func (iter Iterator) Token() Token {
return Token(iter.lexer.Token)
func (iter *Iterator) unreadByte() {
if iter.head == 0 {
iter.ReportError("unreadByte", "unread too many bytes")
return
}
iter.head -= 1
return
}
func (iter *Iterator) OnError(err error) {
if iter.ErrorHandler == nil {
panic(err.Error())
const maxUint64 = (1 << 64 - 1)
const cutoffUint64 = maxUint64 / 10 + 1
const maxUint32 = (1 << 32 - 1)
const cutoffUint32 = maxUint32 / 10 + 1
func (iter *Iterator) ReadUint64() (ret uint64) {
c := iter.readByte()
if iter.Error != nil {
return
}
/* a single zero, or a series of integers */
if c == '0' {
return 0
} else if c >= '1' && c <= '9' {
for c >= '0' && c <= '9' {
var v byte
v = c - '0'
if ret >= cutoffUint64 {
iter.ReportError("ReadUint64", "overflow")
return
}
ret = ret * uint64(10) + uint64(v)
c = iter.readByte()
if iter.Error != nil {
if iter.Error == io.EOF {
break
} else {
return 0
}
}
}
if iter.Error != io.EOF {
iter.unreadByte()
}
} else {
iter.ErrorHandler(err)
iter.ReportError("ReadUint64", "expects 0~9")
return
}
}
return ret
}
func (iter *Iterator) ReadInt64() (ret int64) {
c := iter.readByte()
if iter.Error != nil {
return
}
/* optional leading minus */
if c == '-' {
n := iter.ReadUint64()
return -int64(n)
} else {
iter.unreadByte()
n := iter.ReadUint64()
return int64(n)
}
}
func (iter *Iterator) ReadString() (ret string) {
str := make([]byte, 0, 10)
c := iter.readByte()
if iter.Error != nil {
return
}
if c != '"' {
iter.ReportError("ReadString", "expects quote")
return
}
for {
c = iter.readByte()
if iter.Error != nil {
return
}
switch c {
case '\\':
c = iter.readByte()
if iter.Error != nil {
return
}
switch c {
case 'u':
r := iter.readU4()
if iter.Error != nil {
return
}
if utf16.IsSurrogate(r) {
c = iter.readByte()
if iter.Error != nil {
return
}
if c != '\\' {
iter.ReportError("ReadString",
`expects \u after utf16 surrogate, but \ not found`)
return
}
c = iter.readByte()
if iter.Error != nil {
return
}
if c != 'u' {
iter.ReportError("ReadString",
`expects \u after utf16 surrogate, but \u not found`)
return
}
r2 := iter.readU4()
if iter.Error != nil {
return
}
combined := utf16.DecodeRune(r, r2)
str = appendRune(str, combined)
} else {
str = appendRune(str, r)
}
case '"':
str = append(str, '"')
case '\\':
str = append(str, '\\')
case '/':
str = append(str, '/')
case 'b':
str = append(str, '\b')
case 'f':
str = append(str, '\f')
case 'n':
str = append(str, '\n')
case 'r':
str = append(str, '\r')
case 't':
str = append(str, '\t')
default:
iter.ReportError("ReadString",
`invalid escape char after \`)
return
}
case '"':
return string(str)
default:
str = append(str, c)
}
}
}
func (iter *Iterator) readU4() (ret rune) {
for i := 0; i < 4; i++ {
c := iter.readByte()
if iter.Error != nil {
return
}
if (c >= '0' && c <= '9') {
if ret >= cutoffUint32 {
iter.ReportError("readU4", "overflow")
return
}
ret = ret * 16 + rune(c - '0')
} else if ((c >= 'a' && c <= 'f') ) {
if ret >= cutoffUint32 {
iter.ReportError("readU4", "overflow")
return
}
ret = ret * 16 + rune(c - 'a' + 10)
} else {
iter.ReportError("readU4", "expects 0~9 or a~f")
return
}
}
return ret
}
const (
t1 = 0x00 // 0000 0000
tx = 0x80 // 1000 0000
t2 = 0xC0 // 1100 0000
t3 = 0xE0 // 1110 0000
t4 = 0xF0 // 1111 0000
t5 = 0xF8 // 1111 1000
maskx = 0x3F // 0011 1111
mask2 = 0x1F // 0001 1111
mask3 = 0x0F // 0000 1111
mask4 = 0x07 // 0000 0111
rune1Max = 1 << 7 - 1
rune2Max = 1 << 11 - 1
rune3Max = 1 << 16 - 1
surrogateMin = 0xD800
surrogateMax = 0xDFFF
MaxRune = '\U0010FFFF' // Maximum valid Unicode code point.
RuneError = '\uFFFD' // the "error" Rune or "Unicode replacement character"
)
func appendRune(p []byte, r rune) []byte {
// Negative values are erroneous. Making it unsigned addresses the problem.
switch i := uint32(r); {
case i <= rune1Max:
p = append(p, byte(r))
return p
case i <= rune2Max:
p = append(p, t2 | byte(r >> 6))
p = append(p, tx | byte(r) & maskx)
return p
case i > MaxRune, surrogateMin <= i && i <= surrogateMax:
r = RuneError
fallthrough
case i <= rune3Max:
p = append(p, t3 | byte(r >> 12))
p = append(p, tx | byte(r >> 6) & maskx)
p = append(p, tx | byte(r) & maskx)
return p
default:
p = append(p, t4 | byte(r >> 18))
p = append(p, tx | byte(r >> 12) & maskx)
p = append(p, tx | byte(r >> 6) & maskx)
p = append(p, tx | byte(r) & maskx)
return p
}
}