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-rw-r--r--libgo/go/json/decode.go861
1 files changed, 861 insertions, 0 deletions
diff --git a/libgo/go/json/decode.go b/libgo/go/json/decode.go
new file mode 100644
index 000000000..ff91dd83c
--- /dev/null
+++ b/libgo/go/json/decode.go
@@ -0,0 +1,861 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Represents JSON data structure using native Go types: booleans, floats,
+// strings, arrays, and maps.
+
+package json
+
+import (
+ "container/vector"
+ "os"
+ "reflect"
+ "runtime"
+ "strconv"
+ "strings"
+ "unicode"
+ "utf16"
+ "utf8"
+)
+
+// Unmarshal parses the JSON-encoded data and stores the result
+// in the value pointed to by v.
+//
+// Unmarshal traverses the value v recursively.
+// If an encountered value implements the Unmarshaler interface,
+// Unmarshal calls its UnmarshalJSON method with a well-formed
+// JSON encoding.
+//
+// Otherwise, Unmarshal uses the inverse of the encodings that
+// Marshal uses, allocating maps, slices, and pointers as necessary,
+// with the following additional rules:
+//
+// To unmarshal a JSON value into a nil interface value, the
+// type stored in the interface value is one of:
+//
+// bool, for JSON booleans
+// float64, for JSON numbers
+// string, for JSON strings
+// []interface{}, for JSON arrays
+// map[string]interface{}, for JSON objects
+// nil for JSON null
+//
+// If a JSON value is not appropriate for a given target type,
+// or if a JSON number overflows the target type, Unmarshal
+// skips that field and completes the unmarshalling as best it can.
+// If no more serious errors are encountered, Unmarshal returns
+// an UnmarshalTypeError describing the earliest such error.
+//
+func Unmarshal(data []byte, v interface{}) os.Error {
+ d := new(decodeState).init(data)
+
+ // Quick check for well-formedness.
+ // Avoids filling out half a data structure
+ // before discovering a JSON syntax error.
+ err := checkValid(data, &d.scan)
+ if err != nil {
+ return err
+ }
+
+ return d.unmarshal(v)
+}
+
+// Unmarshaler is the interface implemented by objects
+// that can unmarshal a JSON description of themselves.
+// The input can be assumed to be a valid JSON object
+// encoding. UnmarshalJSON must copy the JSON data
+// if it wishes to retain the data after returning.
+type Unmarshaler interface {
+ UnmarshalJSON([]byte) os.Error
+}
+
+
+// An UnmarshalTypeError describes a JSON value that was
+// not appropriate for a value of a specific Go type.
+type UnmarshalTypeError struct {
+ Value string // description of JSON value - "bool", "array", "number -5"
+ Type reflect.Type // type of Go value it could not be assigned to
+}
+
+func (e *UnmarshalTypeError) String() string {
+ return "json: cannot unmarshal " + e.Value + " into Go value of type " + e.Type.String()
+}
+
+// An UnmarshalFieldError describes a JSON object key that
+// led to an unexported (and therefore unwritable) struct field.
+type UnmarshalFieldError struct {
+ Key string
+ Type *reflect.StructType
+ Field reflect.StructField
+}
+
+func (e *UnmarshalFieldError) String() string {
+ return "json: cannot unmarshal object key " + strconv.Quote(e.Key) + " into unexported field " + e.Field.Name + " of type " + e.Type.String()
+}
+
+// An InvalidUnmarshalError describes an invalid argument passed to Unmarshal.
+// (The argument to Unmarshal must be a non-nil pointer.)
+type InvalidUnmarshalError struct {
+ Type reflect.Type
+}
+
+func (e *InvalidUnmarshalError) String() string {
+ if e.Type == nil {
+ return "json: Unmarshal(nil)"
+ }
+
+ if _, ok := e.Type.(*reflect.PtrType); !ok {
+ return "json: Unmarshal(non-pointer " + e.Type.String() + ")"
+ }
+ return "json: Unmarshal(nil " + e.Type.String() + ")"
+}
+
+func (d *decodeState) unmarshal(v interface{}) (err os.Error) {
+ defer func() {
+ if r := recover(); r != nil {
+ if _, ok := r.(runtime.Error); ok {
+ panic(r)
+ }
+ err = r.(os.Error)
+ }
+ }()
+
+ rv := reflect.NewValue(v)
+ pv, ok := rv.(*reflect.PtrValue)
+ if !ok || pv.IsNil() {
+ return &InvalidUnmarshalError{reflect.Typeof(v)}
+ }
+
+ d.scan.reset()
+ // We decode rv not pv.Elem because the Unmarshaler interface
+ // test must be applied at the top level of the value.
+ d.value(rv)
+ return d.savedError
+}
+
+// decodeState represents the state while decoding a JSON value.
+type decodeState struct {
+ data []byte
+ off int // read offset in data
+ scan scanner
+ nextscan scanner // for calls to nextValue
+ savedError os.Error
+}
+
+// errPhase is used for errors that should not happen unless
+// there is a bug in the JSON decoder or something is editing
+// the data slice while the decoder executes.
+var errPhase = os.NewError("JSON decoder out of sync - data changing underfoot?")
+
+func (d *decodeState) init(data []byte) *decodeState {
+ d.data = data
+ d.off = 0
+ d.savedError = nil
+ return d
+}
+
+// error aborts the decoding by panicking with err.
+func (d *decodeState) error(err os.Error) {
+ panic(err)
+}
+
+// saveError saves the first err it is called with,
+// for reporting at the end of the unmarshal.
+func (d *decodeState) saveError(err os.Error) {
+ if d.savedError == nil {
+ d.savedError = err
+ }
+}
+
+// next cuts off and returns the next full JSON value in d.data[d.off:].
+// The next value is known to be an object or array, not a literal.
+func (d *decodeState) next() []byte {
+ c := d.data[d.off]
+ item, rest, err := nextValue(d.data[d.off:], &d.nextscan)
+ if err != nil {
+ d.error(err)
+ }
+ d.off = len(d.data) - len(rest)
+
+ // Our scanner has seen the opening brace/bracket
+ // and thinks we're still in the middle of the object.
+ // invent a closing brace/bracket to get it out.
+ if c == '{' {
+ d.scan.step(&d.scan, '}')
+ } else {
+ d.scan.step(&d.scan, ']')
+ }
+
+ return item
+}
+
+// scanWhile processes bytes in d.data[d.off:] until it
+// receives a scan code not equal to op.
+// It updates d.off and returns the new scan code.
+func (d *decodeState) scanWhile(op int) int {
+ var newOp int
+ for {
+ if d.off >= len(d.data) {
+ newOp = d.scan.eof()
+ d.off = len(d.data) + 1 // mark processed EOF with len+1
+ } else {
+ c := int(d.data[d.off])
+ d.off++
+ newOp = d.scan.step(&d.scan, c)
+ }
+ if newOp != op {
+ break
+ }
+ }
+ return newOp
+}
+
+// value decodes a JSON value from d.data[d.off:] into the value.
+// it updates d.off to point past the decoded value.
+func (d *decodeState) value(v reflect.Value) {
+ if v == nil {
+ _, rest, err := nextValue(d.data[d.off:], &d.nextscan)
+ if err != nil {
+ d.error(err)
+ }
+ d.off = len(d.data) - len(rest)
+
+ // d.scan thinks we're still at the beginning of the item.
+ // Feed in an empty string - the shortest, simplest value -
+ // so that it knows we got to the end of the value.
+ if d.scan.step == stateRedo {
+ panic("redo")
+ }
+ d.scan.step(&d.scan, '"')
+ d.scan.step(&d.scan, '"')
+ return
+ }
+
+ switch op := d.scanWhile(scanSkipSpace); op {
+ default:
+ d.error(errPhase)
+
+ case scanBeginArray:
+ d.array(v)
+
+ case scanBeginObject:
+ d.object(v)
+
+ case scanBeginLiteral:
+ d.literal(v)
+ }
+}
+
+// indirect walks down v allocating pointers as needed,
+// until it gets to a non-pointer.
+// if it encounters an Unmarshaler, indirect stops and returns that.
+// if wantptr is true, indirect stops at the last pointer.
+func (d *decodeState) indirect(v reflect.Value, wantptr bool) (Unmarshaler, reflect.Value) {
+ for {
+ var isUnmarshaler bool
+ if v.Type().NumMethod() > 0 {
+ // Remember that this is an unmarshaler,
+ // but wait to return it until after allocating
+ // the pointer (if necessary).
+ _, isUnmarshaler = v.Interface().(Unmarshaler)
+ }
+
+ if iv, ok := v.(*reflect.InterfaceValue); ok && !iv.IsNil() {
+ v = iv.Elem()
+ continue
+ }
+ pv, ok := v.(*reflect.PtrValue)
+ if !ok {
+ break
+ }
+ _, isptrptr := pv.Elem().(*reflect.PtrValue)
+ if !isptrptr && wantptr && !isUnmarshaler {
+ return nil, pv
+ }
+ if pv.IsNil() {
+ pv.PointTo(reflect.MakeZero(pv.Type().(*reflect.PtrType).Elem()))
+ }
+ if isUnmarshaler {
+ // Using v.Interface().(Unmarshaler)
+ // here means that we have to use a pointer
+ // as the struct field. We cannot use a value inside
+ // a pointer to a struct, because in that case
+ // v.Interface() is the value (x.f) not the pointer (&x.f).
+ // This is an unfortunate consequence of reflect.
+ // An alternative would be to look up the
+ // UnmarshalJSON method and return a FuncValue.
+ return v.Interface().(Unmarshaler), nil
+ }
+ v = pv.Elem()
+ }
+ return nil, v
+}
+
+// array consumes an array from d.data[d.off-1:], decoding into the value v.
+// the first byte of the array ('[') has been read already.
+func (d *decodeState) array(v reflect.Value) {
+ // Check for unmarshaler.
+ unmarshaler, pv := d.indirect(v, false)
+ if unmarshaler != nil {
+ d.off--
+ err := unmarshaler.UnmarshalJSON(d.next())
+ if err != nil {
+ d.error(err)
+ }
+ return
+ }
+ v = pv
+
+ // Decoding into nil interface? Switch to non-reflect code.
+ iv, ok := v.(*reflect.InterfaceValue)
+ if ok {
+ iv.Set(reflect.NewValue(d.arrayInterface()))
+ return
+ }
+
+ // Check type of target.
+ av, ok := v.(reflect.ArrayOrSliceValue)
+ if !ok {
+ d.saveError(&UnmarshalTypeError{"array", v.Type()})
+ d.off--
+ d.next()
+ return
+ }
+
+ sv, _ := v.(*reflect.SliceValue)
+
+ i := 0
+ for {
+ // Look ahead for ] - can only happen on first iteration.
+ op := d.scanWhile(scanSkipSpace)
+ if op == scanEndArray {
+ break
+ }
+
+ // Back up so d.value can have the byte we just read.
+ d.off--
+ d.scan.undo(op)
+
+ // Get element of array, growing if necessary.
+ if i >= av.Cap() && sv != nil {
+ newcap := sv.Cap() + sv.Cap()/2
+ if newcap < 4 {
+ newcap = 4
+ }
+ newv := reflect.MakeSlice(sv.Type().(*reflect.SliceType), sv.Len(), newcap)
+ reflect.Copy(newv, sv)
+ sv.Set(newv)
+ }
+ if i >= av.Len() && sv != nil {
+ // Must be slice; gave up on array during i >= av.Cap().
+ sv.SetLen(i + 1)
+ }
+
+ // Decode into element.
+ if i < av.Len() {
+ d.value(av.Elem(i))
+ } else {
+ // Ran out of fixed array: skip.
+ d.value(nil)
+ }
+ i++
+
+ // Next token must be , or ].
+ op = d.scanWhile(scanSkipSpace)
+ if op == scanEndArray {
+ break
+ }
+ if op != scanArrayValue {
+ d.error(errPhase)
+ }
+ }
+ if i < av.Len() {
+ if sv == nil {
+ // Array. Zero the rest.
+ z := reflect.MakeZero(av.Type().(*reflect.ArrayType).Elem())
+ for ; i < av.Len(); i++ {
+ av.Elem(i).SetValue(z)
+ }
+ } else {
+ sv.SetLen(i)
+ }
+ }
+}
+
+// matchName returns true if key should be written to a field named name.
+func matchName(key, name string) bool {
+ return strings.ToLower(key) == strings.ToLower(name)
+}
+
+// object consumes an object from d.data[d.off-1:], decoding into the value v.
+// the first byte of the object ('{') has been read already.
+func (d *decodeState) object(v reflect.Value) {
+ // Check for unmarshaler.
+ unmarshaler, pv := d.indirect(v, false)
+ if unmarshaler != nil {
+ d.off--
+ err := unmarshaler.UnmarshalJSON(d.next())
+ if err != nil {
+ d.error(err)
+ }
+ return
+ }
+ v = pv
+
+ // Decoding into nil interface? Switch to non-reflect code.
+ iv, ok := v.(*reflect.InterfaceValue)
+ if ok {
+ iv.Set(reflect.NewValue(d.objectInterface()))
+ return
+ }
+
+ // Check type of target: struct or map[string]T
+ var (
+ mv *reflect.MapValue
+ sv *reflect.StructValue
+ )
+ switch v := v.(type) {
+ case *reflect.MapValue:
+ // map must have string type
+ t := v.Type().(*reflect.MapType)
+ if t.Key() != reflect.Typeof("") {
+ d.saveError(&UnmarshalTypeError{"object", v.Type()})
+ break
+ }
+ mv = v
+ if mv.IsNil() {
+ mv.SetValue(reflect.MakeMap(t))
+ }
+ case *reflect.StructValue:
+ sv = v
+ default:
+ d.saveError(&UnmarshalTypeError{"object", v.Type()})
+ }
+
+ if mv == nil && sv == nil {
+ d.off--
+ d.next() // skip over { } in input
+ return
+ }
+
+ for {
+ // Read opening " of string key or closing }.
+ op := d.scanWhile(scanSkipSpace)
+ if op == scanEndObject {
+ // closing } - can only happen on first iteration.
+ break
+ }
+ if op != scanBeginLiteral {
+ d.error(errPhase)
+ }
+
+ // Read string key.
+ start := d.off - 1
+ op = d.scanWhile(scanContinue)
+ item := d.data[start : d.off-1]
+ key, ok := unquote(item)
+ if !ok {
+ d.error(errPhase)
+ }
+
+ // Figure out field corresponding to key.
+ var subv reflect.Value
+ if mv != nil {
+ subv = reflect.MakeZero(mv.Type().(*reflect.MapType).Elem())
+ } else {
+ var f reflect.StructField
+ var ok bool
+ // First try for field with that tag.
+ st := sv.Type().(*reflect.StructType)
+ for i := 0; i < sv.NumField(); i++ {
+ f = st.Field(i)
+ if f.Tag == key {
+ ok = true
+ break
+ }
+ }
+ if !ok {
+ // Second, exact match.
+ f, ok = st.FieldByName(key)
+ }
+ if !ok {
+ // Third, case-insensitive match.
+ f, ok = st.FieldByNameFunc(func(s string) bool { return matchName(key, s) })
+ }
+
+ // Extract value; name must be exported.
+ if ok {
+ if f.PkgPath != "" {
+ d.saveError(&UnmarshalFieldError{key, st, f})
+ } else {
+ subv = sv.FieldByIndex(f.Index)
+ }
+ }
+ }
+
+ // Read : before value.
+ if op == scanSkipSpace {
+ op = d.scanWhile(scanSkipSpace)
+ }
+ if op != scanObjectKey {
+ d.error(errPhase)
+ }
+
+ // Read value.
+ d.value(subv)
+
+ // Write value back to map;
+ // if using struct, subv points into struct already.
+ if mv != nil {
+ mv.SetElem(reflect.NewValue(key), subv)
+ }
+
+ // Next token must be , or }.
+ op = d.scanWhile(scanSkipSpace)
+ if op == scanEndObject {
+ break
+ }
+ if op != scanObjectValue {
+ d.error(errPhase)
+ }
+ }
+}
+
+// literal consumes a literal from d.data[d.off-1:], decoding into the value v.
+// The first byte of the literal has been read already
+// (that's how the caller knows it's a literal).
+func (d *decodeState) literal(v reflect.Value) {
+ // All bytes inside literal return scanContinue op code.
+ start := d.off - 1
+ op := d.scanWhile(scanContinue)
+
+ // Scan read one byte too far; back up.
+ d.off--
+ d.scan.undo(op)
+ item := d.data[start:d.off]
+
+ // Check for unmarshaler.
+ wantptr := item[0] == 'n' // null
+ unmarshaler, pv := d.indirect(v, wantptr)
+ if unmarshaler != nil {
+ err := unmarshaler.UnmarshalJSON(item)
+ if err != nil {
+ d.error(err)
+ }
+ return
+ }
+ v = pv
+
+ switch c := item[0]; c {
+ case 'n': // null
+ switch v.(type) {
+ default:
+ d.saveError(&UnmarshalTypeError{"null", v.Type()})
+ case *reflect.InterfaceValue, *reflect.PtrValue, *reflect.MapValue:
+ v.SetValue(nil)
+ }
+
+ case 't', 'f': // true, false
+ value := c == 't'
+ switch v := v.(type) {
+ default:
+ d.saveError(&UnmarshalTypeError{"bool", v.Type()})
+ case *reflect.BoolValue:
+ v.Set(value)
+ case *reflect.InterfaceValue:
+ v.Set(reflect.NewValue(value))
+ }
+
+ case '"': // string
+ s, ok := unquote(item)
+ if !ok {
+ d.error(errPhase)
+ }
+ switch v := v.(type) {
+ default:
+ d.saveError(&UnmarshalTypeError{"string", v.Type()})
+ case *reflect.StringValue:
+ v.Set(s)
+ case *reflect.InterfaceValue:
+ v.Set(reflect.NewValue(s))
+ }
+
+ default: // number
+ if c != '-' && (c < '0' || c > '9') {
+ d.error(errPhase)
+ }
+ s := string(item)
+ switch v := v.(type) {
+ default:
+ d.error(&UnmarshalTypeError{"number", v.Type()})
+ case *reflect.InterfaceValue:
+ n, err := strconv.Atof64(s)
+ if err != nil {
+ d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
+ break
+ }
+ v.Set(reflect.NewValue(n))
+
+ case *reflect.IntValue:
+ n, err := strconv.Atoi64(s)
+ if err != nil || v.Overflow(n) {
+ d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
+ break
+ }
+ v.Set(n)
+
+ case *reflect.UintValue:
+ n, err := strconv.Atoui64(s)
+ if err != nil || v.Overflow(n) {
+ d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
+ break
+ }
+ v.Set(n)
+
+ case *reflect.FloatValue:
+ n, err := strconv.AtofN(s, v.Type().Bits())
+ if err != nil || v.Overflow(n) {
+ d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
+ break
+ }
+ v.Set(n)
+ }
+ }
+}
+
+// The xxxInterface routines build up a value to be stored
+// in an empty interface. They are not strictly necessary,
+// but they avoid the weight of reflection in this common case.
+
+// valueInterface is like value but returns interface{}
+func (d *decodeState) valueInterface() interface{} {
+ switch d.scanWhile(scanSkipSpace) {
+ default:
+ d.error(errPhase)
+ case scanBeginArray:
+ return d.arrayInterface()
+ case scanBeginObject:
+ return d.objectInterface()
+ case scanBeginLiteral:
+ return d.literalInterface()
+ }
+ panic("unreachable")
+}
+
+// arrayInterface is like array but returns []interface{}.
+func (d *decodeState) arrayInterface() []interface{} {
+ var v vector.Vector
+ for {
+ // Look ahead for ] - can only happen on first iteration.
+ op := d.scanWhile(scanSkipSpace)
+ if op == scanEndArray {
+ break
+ }
+
+ // Back up so d.value can have the byte we just read.
+ d.off--
+ d.scan.undo(op)
+
+ v.Push(d.valueInterface())
+
+ // Next token must be , or ].
+ op = d.scanWhile(scanSkipSpace)
+ if op == scanEndArray {
+ break
+ }
+ if op != scanArrayValue {
+ d.error(errPhase)
+ }
+ }
+ return v
+}
+
+// objectInterface is like object but returns map[string]interface{}.
+func (d *decodeState) objectInterface() map[string]interface{} {
+ m := make(map[string]interface{})
+ for {
+ // Read opening " of string key or closing }.
+ op := d.scanWhile(scanSkipSpace)
+ if op == scanEndObject {
+ // closing } - can only happen on first iteration.
+ break
+ }
+ if op != scanBeginLiteral {
+ d.error(errPhase)
+ }
+
+ // Read string key.
+ start := d.off - 1
+ op = d.scanWhile(scanContinue)
+ item := d.data[start : d.off-1]
+ key, ok := unquote(item)
+ if !ok {
+ d.error(errPhase)
+ }
+
+ // Read : before value.
+ if op == scanSkipSpace {
+ op = d.scanWhile(scanSkipSpace)
+ }
+ if op != scanObjectKey {
+ d.error(errPhase)
+ }
+
+ // Read value.
+ m[key] = d.valueInterface()
+
+ // Next token must be , or }.
+ op = d.scanWhile(scanSkipSpace)
+ if op == scanEndObject {
+ break
+ }
+ if op != scanObjectValue {
+ d.error(errPhase)
+ }
+ }
+ return m
+}
+
+
+// literalInterface is like literal but returns an interface value.
+func (d *decodeState) literalInterface() interface{} {
+ // All bytes inside literal return scanContinue op code.
+ start := d.off - 1
+ op := d.scanWhile(scanContinue)
+
+ // Scan read one byte too far; back up.
+ d.off--
+ d.scan.undo(op)
+ item := d.data[start:d.off]
+
+ switch c := item[0]; c {
+ case 'n': // null
+ return nil
+
+ case 't', 'f': // true, false
+ return c == 't'
+
+ case '"': // string
+ s, ok := unquote(item)
+ if !ok {
+ d.error(errPhase)
+ }
+ return s
+
+ default: // number
+ if c != '-' && (c < '0' || c > '9') {
+ d.error(errPhase)
+ }
+ n, err := strconv.Atof64(string(item))
+ if err != nil {
+ d.saveError(&UnmarshalTypeError{"number " + string(item), reflect.Typeof(0.0)})
+ }
+ return n
+ }
+ panic("unreachable")
+}
+
+// getu4 decodes \uXXXX from the beginning of s, returning the hex value,
+// or it returns -1.
+func getu4(s []byte) int {
+ if len(s) < 6 || s[0] != '\\' || s[1] != 'u' {
+ return -1
+ }
+ rune, err := strconv.Btoui64(string(s[2:6]), 16)
+ if err != nil {
+ return -1
+ }
+ return int(rune)
+}
+
+// unquote converts a quoted JSON string literal s into an actual string t.
+// The rules are different than for Go, so cannot use strconv.Unquote.
+func unquote(s []byte) (t string, ok bool) {
+ if len(s) < 2 || s[0] != '"' || s[len(s)-1] != '"' {
+ return
+ }
+ b := make([]byte, len(s)+2*utf8.UTFMax)
+ w := 0
+ for r := 1; r < len(s)-1; {
+ // Out of room? Can only happen if s is full of
+ // malformed UTF-8 and we're replacing each
+ // byte with RuneError.
+ if w >= len(b)-2*utf8.UTFMax {
+ nb := make([]byte, (len(b)+utf8.UTFMax)*2)
+ copy(nb, b[0:w])
+ b = nb
+ }
+ switch c := s[r]; {
+ case c == '\\':
+ r++
+ if r >= len(s)-1 {
+ return
+ }
+ switch s[r] {
+ default:
+ return
+ case '"', '\\', '/', '\'':
+ b[w] = s[r]
+ r++
+ w++
+ case 'b':
+ b[w] = '\b'
+ r++
+ w++
+ case 'f':
+ b[w] = '\f'
+ r++
+ w++
+ case 'n':
+ b[w] = '\n'
+ r++
+ w++
+ case 'r':
+ b[w] = '\r'
+ r++
+ w++
+ case 't':
+ b[w] = '\t'
+ r++
+ w++
+ case 'u':
+ r--
+ rune := getu4(s[r:])
+ if rune < 0 {
+ return
+ }
+ r += 6
+ if utf16.IsSurrogate(rune) {
+ rune1 := getu4(s[r:])
+ if dec := utf16.DecodeRune(rune, rune1); dec != unicode.ReplacementChar {
+ // A valid pair; consume.
+ r += 6
+ w += utf8.EncodeRune(b[w:], dec)
+ break
+ }
+ // Invalid surrogate; fall back to replacement rune.
+ rune = unicode.ReplacementChar
+ }
+ w += utf8.EncodeRune(b[w:], rune)
+ }
+
+ // Quote, control characters are invalid.
+ case c == '"', c < ' ':
+ return
+
+ // ASCII
+ case c < utf8.RuneSelf:
+ b[w] = c
+ r++
+ w++
+
+ // Coerce to well-formed UTF-8.
+ default:
+ rune, size := utf8.DecodeRune(s[r:])
+ r += size
+ w += utf8.EncodeRune(b[w:], rune)
+ }
+ }
+ return string(b[0:w]), true
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-09 19:42:42 +0000