service/vendor/github.com/bytedance/sonic/ast/parser.go

661 lines
16 KiB
Go

/*
* Copyright 2021 ByteDance 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 ast
import (
`fmt`
`github.com/bytedance/sonic/internal/native/types`
`github.com/bytedance/sonic/internal/rt`
)
const (
_DEFAULT_NODE_CAP int = 8
_APPEND_GROW_SHIFT = 1
)
const (
_ERR_NOT_FOUND types.ParsingError = 33
_ERR_UNSUPPORT_TYPE types.ParsingError = 34
)
var (
// ErrNotExist means both key and value doesn't exist
ErrNotExist error = newError(_ERR_NOT_FOUND, "value not exists")
// ErrUnsupportType means API on the node is unsupported
ErrUnsupportType error = newError(_ERR_UNSUPPORT_TYPE, "unsupported type")
)
type Parser struct {
p int
s string
noLazy bool
skipValue bool
dbuf *byte
}
/** Parser Private Methods **/
func (self *Parser) delim() types.ParsingError {
n := len(self.s)
p := self.lspace(self.p)
/* check for EOF */
if p >= n {
return types.ERR_EOF
}
/* check for the delimtier */
if self.s[p] != ':' {
return types.ERR_INVALID_CHAR
}
/* update the read pointer */
self.p = p + 1
return 0
}
func (self *Parser) object() types.ParsingError {
n := len(self.s)
p := self.lspace(self.p)
/* check for EOF */
if p >= n {
return types.ERR_EOF
}
/* check for the delimtier */
if self.s[p] != '{' {
return types.ERR_INVALID_CHAR
}
/* update the read pointer */
self.p = p + 1
return 0
}
func (self *Parser) array() types.ParsingError {
n := len(self.s)
p := self.lspace(self.p)
/* check for EOF */
if p >= n {
return types.ERR_EOF
}
/* check for the delimtier */
if self.s[p] != '[' {
return types.ERR_INVALID_CHAR
}
/* update the read pointer */
self.p = p + 1
return 0
}
func (self *Parser) lspace(sp int) int {
ns := len(self.s)
for ; sp<ns && isSpace(self.s[sp]); sp+=1 {}
return sp
}
func (self *Parser) decodeArray(ret *linkedNodes) (Node, types.ParsingError) {
sp := self.p
ns := len(self.s)
/* check for EOF */
if self.p = self.lspace(sp); self.p >= ns {
return Node{}, types.ERR_EOF
}
/* check for empty array */
if self.s[self.p] == ']' {
self.p++
return Node{t: types.V_ARRAY}, 0
}
/* allocate array space and parse every element */
for {
var val Node
var err types.ParsingError
if self.skipValue {
/* skip the value */
var start int
if start, err = self.skipFast(); err != 0 {
return Node{}, err
}
if self.p > ns {
return Node{}, types.ERR_EOF
}
t := switchRawType(self.s[start])
if t == _V_NONE {
return Node{}, types.ERR_INVALID_CHAR
}
val = newRawNode(self.s[start:self.p], t)
}else{
/* decode the value */
if val, err = self.Parse(); err != 0 {
return Node{}, err
}
}
/* add the value to result */
ret.Push(val)
self.p = self.lspace(self.p)
/* check for EOF */
if self.p >= ns {
return Node{}, types.ERR_EOF
}
/* check for the next character */
switch self.s[self.p] {
case ',' : self.p++
case ']' : self.p++; return newArray(ret), 0
default:
// if val.isLazy() {
// return newLazyArray(self, ret), 0
// }
return Node{}, types.ERR_INVALID_CHAR
}
}
}
func (self *Parser) decodeObject(ret *linkedPairs) (Node, types.ParsingError) {
sp := self.p
ns := len(self.s)
/* check for EOF */
if self.p = self.lspace(sp); self.p >= ns {
return Node{}, types.ERR_EOF
}
/* check for empty object */
if self.s[self.p] == '}' {
self.p++
return Node{t: types.V_OBJECT}, 0
}
/* decode each pair */
for {
var val Node
var njs types.JsonState
var err types.ParsingError
/* decode the key */
if njs = self.decodeValue(); njs.Vt != types.V_STRING {
return Node{}, types.ERR_INVALID_CHAR
}
/* extract the key */
idx := self.p - 1
key := self.s[njs.Iv:idx]
/* check for escape sequence */
if njs.Ep != -1 {
if key, err = unquote(key); err != 0 {
return Node{}, err
}
}
/* expect a ':' delimiter */
if err = self.delim(); err != 0 {
return Node{}, err
}
if self.skipValue {
/* skip the value */
var start int
if start, err = self.skipFast(); err != 0 {
return Node{}, err
}
if self.p > ns {
return Node{}, types.ERR_EOF
}
t := switchRawType(self.s[start])
if t == _V_NONE {
return Node{}, types.ERR_INVALID_CHAR
}
val = newRawNode(self.s[start:self.p], t)
} else {
/* decode the value */
if val, err = self.Parse(); err != 0 {
return Node{}, err
}
}
/* add the value to result */
// FIXME: ret's address may change here, thus previous referred node in ret may be invalid !!
ret.Push(Pair{Key: key, Value: val})
self.p = self.lspace(self.p)
/* check for EOF */
if self.p >= ns {
return Node{}, types.ERR_EOF
}
/* check for the next character */
switch self.s[self.p] {
case ',' : self.p++
case '}' : self.p++; return newObject(ret), 0
default:
// if val.isLazy() {
// return newLazyObject(self, ret), 0
// }
return Node{}, types.ERR_INVALID_CHAR
}
}
}
func (self *Parser) decodeString(iv int64, ep int) (Node, types.ParsingError) {
p := self.p - 1
s := self.s[iv:p]
/* fast path: no escape sequence */
if ep == -1 {
return NewString(s), 0
}
/* unquote the string */
out, err := unquote(s)
/* check for errors */
if err != 0 {
return Node{}, err
} else {
return newBytes(rt.Str2Mem(out)), 0
}
}
/** Parser Interface **/
func (self *Parser) Pos() int {
return self.p
}
func (self *Parser) Parse() (Node, types.ParsingError) {
switch val := self.decodeValue(); val.Vt {
case types.V_EOF : return Node{}, types.ERR_EOF
case types.V_NULL : return nullNode, 0
case types.V_TRUE : return trueNode, 0
case types.V_FALSE : return falseNode, 0
case types.V_STRING : return self.decodeString(val.Iv, val.Ep)
case types.V_ARRAY:
if p := skipBlank(self.s, self.p); p >= self.p && self.s[p] == ']' {
self.p = p + 1
return Node{t: types.V_ARRAY}, 0
}
if self.noLazy {
return self.decodeArray(new(linkedNodes))
}
return newLazyArray(self), 0
case types.V_OBJECT:
if p := skipBlank(self.s, self.p); p >= self.p && self.s[p] == '}' {
self.p = p + 1
return Node{t: types.V_OBJECT}, 0
}
if self.noLazy {
return self.decodeObject(new(linkedPairs))
}
return newLazyObject(self), 0
case types.V_DOUBLE : return NewNumber(self.s[val.Ep:self.p]), 0
case types.V_INTEGER : return NewNumber(self.s[val.Ep:self.p]), 0
default : return Node{}, types.ParsingError(-val.Vt)
}
}
func (self *Parser) searchKey(match string) types.ParsingError {
ns := len(self.s)
if err := self.object(); err != 0 {
return err
}
/* check for EOF */
if self.p = self.lspace(self.p); self.p >= ns {
return types.ERR_EOF
}
/* check for empty object */
if self.s[self.p] == '}' {
self.p++
return _ERR_NOT_FOUND
}
var njs types.JsonState
var err types.ParsingError
/* decode each pair */
for {
/* decode the key */
if njs = self.decodeValue(); njs.Vt != types.V_STRING {
return types.ERR_INVALID_CHAR
}
/* extract the key */
idx := self.p - 1
key := self.s[njs.Iv:idx]
/* check for escape sequence */
if njs.Ep != -1 {
if key, err = unquote(key); err != 0 {
return err
}
}
/* expect a ':' delimiter */
if err = self.delim(); err != 0 {
return err
}
/* skip value */
if key != match {
if _, err = self.skipFast(); err != 0 {
return err
}
} else {
return 0
}
/* check for EOF */
self.p = self.lspace(self.p)
if self.p >= ns {
return types.ERR_EOF
}
/* check for the next character */
switch self.s[self.p] {
case ',':
self.p++
case '}':
self.p++
return _ERR_NOT_FOUND
default:
return types.ERR_INVALID_CHAR
}
}
}
func (self *Parser) searchIndex(idx int) types.ParsingError {
ns := len(self.s)
if err := self.array(); err != 0 {
return err
}
/* check for EOF */
if self.p = self.lspace(self.p); self.p >= ns {
return types.ERR_EOF
}
/* check for empty array */
if self.s[self.p] == ']' {
self.p++
return _ERR_NOT_FOUND
}
var err types.ParsingError
/* allocate array space and parse every element */
for i := 0; i < idx; i++ {
/* decode the value */
if _, err = self.skipFast(); err != 0 {
return err
}
/* check for EOF */
self.p = self.lspace(self.p)
if self.p >= ns {
return types.ERR_EOF
}
/* check for the next character */
switch self.s[self.p] {
case ',':
self.p++
case ']':
self.p++
return _ERR_NOT_FOUND
default:
return types.ERR_INVALID_CHAR
}
}
return 0
}
func (self *Node) skipNextNode() *Node {
if !self.isLazy() {
return nil
}
parser, stack := self.getParserAndArrayStack()
ret := &stack.v
sp := parser.p
ns := len(parser.s)
/* check for EOF */
if parser.p = parser.lspace(sp); parser.p >= ns {
return newSyntaxError(parser.syntaxError(types.ERR_EOF))
}
/* check for empty array */
if parser.s[parser.p] == ']' {
parser.p++
self.setArray(ret)
return nil
}
var val Node
/* skip the value */
if start, err := parser.skipFast(); err != 0 {
return newSyntaxError(parser.syntaxError(err))
} else {
t := switchRawType(parser.s[start])
if t == _V_NONE {
return newSyntaxError(parser.syntaxError(types.ERR_INVALID_CHAR))
}
val = newRawNode(parser.s[start:parser.p], t)
}
/* add the value to result */
ret.Push(val)
self.l++
parser.p = parser.lspace(parser.p)
/* check for EOF */
if parser.p >= ns {
return newSyntaxError(parser.syntaxError(types.ERR_EOF))
}
/* check for the next character */
switch parser.s[parser.p] {
case ',':
parser.p++
return ret.At(ret.Len()-1)
case ']':
parser.p++
self.setArray(ret)
return ret.At(ret.Len()-1)
default:
return newSyntaxError(parser.syntaxError(types.ERR_INVALID_CHAR))
}
}
func (self *Node) skipNextPair() (*Pair) {
if !self.isLazy() {
return nil
}
parser, stack := self.getParserAndObjectStack()
ret := &stack.v
sp := parser.p
ns := len(parser.s)
/* check for EOF */
if parser.p = parser.lspace(sp); parser.p >= ns {
return &Pair{"", *newSyntaxError(parser.syntaxError(types.ERR_EOF))}
}
/* check for empty object */
if parser.s[parser.p] == '}' {
parser.p++
self.setObject(ret)
return nil
}
/* decode one pair */
var val Node
var njs types.JsonState
var err types.ParsingError
/* decode the key */
if njs = parser.decodeValue(); njs.Vt != types.V_STRING {
return &Pair{"", *newSyntaxError(parser.syntaxError(types.ERR_INVALID_CHAR))}
}
/* extract the key */
idx := parser.p - 1
key := parser.s[njs.Iv:idx]
/* check for escape sequence */
if njs.Ep != -1 {
if key, err = unquote(key); err != 0 {
return &Pair{key, *newSyntaxError(parser.syntaxError(err))}
}
}
/* expect a ':' delimiter */
if err = parser.delim(); err != 0 {
return &Pair{key, *newSyntaxError(parser.syntaxError(err))}
}
/* skip the value */
if start, err := parser.skipFast(); err != 0 {
return &Pair{key, *newSyntaxError(parser.syntaxError(err))}
} else {
t := switchRawType(parser.s[start])
if t == _V_NONE {
return &Pair{key, *newSyntaxError(parser.syntaxError(types.ERR_INVALID_CHAR))}
}
val = newRawNode(parser.s[start:parser.p], t)
}
/* add the value to result */
ret.Push(Pair{Key: key, Value: val})
self.l++
parser.p = parser.lspace(parser.p)
/* check for EOF */
if parser.p >= ns {
return &Pair{key, *newSyntaxError(parser.syntaxError(types.ERR_EOF))}
}
/* check for the next character */
switch parser.s[parser.p] {
case ',':
parser.p++
return ret.At(ret.Len()-1)
case '}':
parser.p++
self.setObject(ret)
return ret.At(ret.Len()-1)
default:
return &Pair{key, *newSyntaxError(parser.syntaxError(types.ERR_INVALID_CHAR))}
}
}
/** Parser Factory **/
// Loads parse all json into interface{}
func Loads(src string) (int, interface{}, error) {
ps := &Parser{s: src}
np, err := ps.Parse()
/* check for errors */
if err != 0 {
return 0, nil, ps.ExportError(err)
} else {
x, err := np.Interface()
if err != nil {
return 0, nil, err
}
return ps.Pos(), x, nil
}
}
// LoadsUseNumber parse all json into interface{}, with numeric nodes casted to json.Number
func LoadsUseNumber(src string) (int, interface{}, error) {
ps := &Parser{s: src}
np, err := ps.Parse()
/* check for errors */
if err != 0 {
return 0, nil, err
} else {
x, err := np.InterfaceUseNumber()
if err != nil {
return 0, nil, err
}
return ps.Pos(), x, nil
}
}
// NewParser returns pointer of new allocated parser
func NewParser(src string) *Parser {
return &Parser{s: src}
}
// NewParser returns new allocated parser
func NewParserObj(src string) Parser {
return Parser{s: src}
}
// decodeNumber controls if parser decodes the number values instead of skip them
// WARN: once you set decodeNumber(true), please set decodeNumber(false) before you drop the parser
// otherwise the memory CANNOT be reused
func (self *Parser) decodeNumber(decode bool) {
if !decode && self.dbuf != nil {
types.FreeDbuf(self.dbuf)
self.dbuf = nil
return
}
if decode && self.dbuf == nil {
self.dbuf = types.NewDbuf()
}
}
// ExportError converts types.ParsingError to std Error
func (self *Parser) ExportError(err types.ParsingError) error {
if err == _ERR_NOT_FOUND {
return ErrNotExist
}
return fmt.Errorf("%q", SyntaxError{
Pos : self.p,
Src : self.s,
Code: err,
}.Description())
}
func backward(src string, i int) int {
for ; i>=0 && isSpace(src[i]); i-- {}
return i
}