diff options
Diffstat (limited to 'gcc-4.8.1/libgo/go/encoding/json/encode.go')
| -rw-r--r-- | gcc-4.8.1/libgo/go/encoding/json/encode.go | 706 |
1 files changed, 0 insertions, 706 deletions
diff --git a/gcc-4.8.1/libgo/go/encoding/json/encode.go b/gcc-4.8.1/libgo/go/encoding/json/encode.go deleted file mode 100644 index fb57f1d51..000000000 --- a/gcc-4.8.1/libgo/go/encoding/json/encode.go +++ /dev/null @@ -1,706 +0,0 @@ -// 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. - -// Package json implements encoding and decoding of JSON objects as defined in -// RFC 4627. -// -// See "JSON and Go" for an introduction to this package: -// http://golang.org/doc/articles/json_and_go.html -package json - -import ( - "bytes" - "encoding/base64" - "math" - "reflect" - "runtime" - "sort" - "strconv" - "strings" - "sync" - "unicode" - "unicode/utf8" -) - -// Marshal returns the JSON encoding of v. -// -// Marshal traverses the value v recursively. -// If an encountered value implements the Marshaler interface -// and is not a nil pointer, Marshal calls its MarshalJSON method -// to produce JSON. The nil pointer exception is not strictly necessary -// but mimics a similar, necessary exception in the behavior of -// UnmarshalJSON. -// -// Otherwise, Marshal uses the following type-dependent default encodings: -// -// Boolean values encode as JSON booleans. -// -// Floating point, integer, and Number values encode as JSON numbers. -// -// String values encode as JSON strings, with each invalid UTF-8 sequence -// replaced by the encoding of the Unicode replacement character U+FFFD. -// The angle brackets "<" and ">" are escaped to "\u003c" and "\u003e" -// to keep some browsers from misinterpreting JSON output as HTML. -// -// Array and slice values encode as JSON arrays, except that -// []byte encodes as a base64-encoded string, and a nil slice -// encodes as the null JSON object. -// -// Struct values encode as JSON objects. Each exported struct field -// becomes a member of the object unless -// - the field's tag is "-", or -// - the field is empty and its tag specifies the "omitempty" option. -// The empty values are false, 0, any -// nil pointer or interface value, and any array, slice, map, or string of -// length zero. The object's default key string is the struct field name -// but can be specified in the struct field's tag value. The "json" key in -// the struct field's tag value is the key name, followed by an optional comma -// and options. Examples: -// -// // Field is ignored by this package. -// Field int `json:"-"` -// -// // Field appears in JSON as key "myName". -// Field int `json:"myName"` -// -// // Field appears in JSON as key "myName" and -// // the field is omitted from the object if its value is empty, -// // as defined above. -// Field int `json:"myName,omitempty"` -// -// // Field appears in JSON as key "Field" (the default), but -// // the field is skipped if empty. -// // Note the leading comma. -// Field int `json:",omitempty"` -// -// The "string" option signals that a field is stored as JSON inside a -// JSON-encoded string. It applies only to fields of string, floating point, -// or integer types. This extra level of encoding is sometimes used when -// communicating with JavaScript programs: -// -// Int64String int64 `json:",string"` -// -// The key name will be used if it's a non-empty string consisting of -// only Unicode letters, digits, dollar signs, percent signs, hyphens, -// underscores and slashes. -// -// Anonymous struct fields are usually marshaled as if their inner exported fields -// were fields in the outer struct, subject to the usual Go visibility rules. -// An anonymous struct field with a name given in its JSON tag is treated as -// having that name instead of as anonymous. -// -// Handling of anonymous struct fields is new in Go 1.1. -// Prior to Go 1.1, anonymous struct fields were ignored. To force ignoring of -// an anonymous struct field in both current and earlier versions, give the field -// a JSON tag of "-". -// -// Map values encode as JSON objects. -// The map's key type must be string; the object keys are used directly -// as map keys. -// -// Pointer values encode as the value pointed to. -// A nil pointer encodes as the null JSON object. -// -// Interface values encode as the value contained in the interface. -// A nil interface value encodes as the null JSON object. -// -// Channel, complex, and function values cannot be encoded in JSON. -// Attempting to encode such a value causes Marshal to return -// an UnsupportedTypeError. -// -// JSON cannot represent cyclic data structures and Marshal does not -// handle them. Passing cyclic structures to Marshal will result in -// an infinite recursion. -// -func Marshal(v interface{}) ([]byte, error) { - e := &encodeState{} - err := e.marshal(v) - if err != nil { - return nil, err - } - return e.Bytes(), nil -} - -// MarshalIndent is like Marshal but applies Indent to format the output. -func MarshalIndent(v interface{}, prefix, indent string) ([]byte, error) { - b, err := Marshal(v) - if err != nil { - return nil, err - } - var buf bytes.Buffer - err = Indent(&buf, b, prefix, indent) - if err != nil { - return nil, err - } - return buf.Bytes(), nil -} - -// HTMLEscape appends to dst the JSON-encoded src with <, >, and & -// characters inside string literals changed to \u003c, \u003e, \u0026 -// so that the JSON will be safe to embed inside HTML <script> tags. -// For historical reasons, web browsers don't honor standard HTML -// escaping within <script> tags, so an alternative JSON encoding must -// be used. -func HTMLEscape(dst *bytes.Buffer, src []byte) { - // < > & can only appear in string literals, - // so just scan the string one byte at a time. - start := 0 - for i, c := range src { - if c == '<' || c == '>' || c == '&' { - if start < i { - dst.Write(src[start:i]) - } - dst.WriteString(`\u00`) - dst.WriteByte(hex[c>>4]) - dst.WriteByte(hex[c&0xF]) - start = i + 1 - } - } - if start < len(src) { - dst.Write(src[start:]) - } -} - -// Marshaler is the interface implemented by objects that -// can marshal themselves into valid JSON. -type Marshaler interface { - MarshalJSON() ([]byte, error) -} - -// An UnsupportedTypeError is returned by Marshal when attempting -// to encode an unsupported value type. -type UnsupportedTypeError struct { - Type reflect.Type -} - -func (e *UnsupportedTypeError) Error() string { - return "json: unsupported type: " + e.Type.String() -} - -type UnsupportedValueError struct { - Value reflect.Value - Str string -} - -func (e *UnsupportedValueError) Error() string { - return "json: unsupported value: " + e.Str -} - -type InvalidUTF8Error struct { - S string -} - -func (e *InvalidUTF8Error) Error() string { - return "json: invalid UTF-8 in string: " + strconv.Quote(e.S) -} - -type MarshalerError struct { - Type reflect.Type - Err error -} - -func (e *MarshalerError) Error() string { - return "json: error calling MarshalJSON for type " + e.Type.String() + ": " + e.Err.Error() -} - -var hex = "0123456789abcdef" - -// An encodeState encodes JSON into a bytes.Buffer. -type encodeState struct { - bytes.Buffer // accumulated output - scratch [64]byte -} - -func (e *encodeState) marshal(v interface{}) (err error) { - defer func() { - if r := recover(); r != nil { - if _, ok := r.(runtime.Error); ok { - panic(r) - } - err = r.(error) - } - }() - e.reflectValue(reflect.ValueOf(v)) - return nil -} - -func (e *encodeState) error(err error) { - panic(err) -} - -var byteSliceType = reflect.TypeOf([]byte(nil)) - -func isEmptyValue(v reflect.Value) bool { - switch v.Kind() { - case reflect.Array, reflect.Map, reflect.Slice, reflect.String: - return v.Len() == 0 - case reflect.Bool: - return !v.Bool() - case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: - return v.Int() == 0 - case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr: - return v.Uint() == 0 - case reflect.Float32, reflect.Float64: - return v.Float() == 0 - case reflect.Interface, reflect.Ptr: - return v.IsNil() - } - return false -} - -func (e *encodeState) reflectValue(v reflect.Value) { - e.reflectValueQuoted(v, false) -} - -// reflectValueQuoted writes the value in v to the output. -// If quoted is true, the serialization is wrapped in a JSON string. -func (e *encodeState) reflectValueQuoted(v reflect.Value, quoted bool) { - if !v.IsValid() { - e.WriteString("null") - return - } - - m, ok := v.Interface().(Marshaler) - if !ok { - // T doesn't match the interface. Check against *T too. - if v.Kind() != reflect.Ptr && v.CanAddr() { - m, ok = v.Addr().Interface().(Marshaler) - if ok { - v = v.Addr() - } - } - } - if ok && (v.Kind() != reflect.Ptr || !v.IsNil()) { - b, err := m.MarshalJSON() - if err == nil { - // copy JSON into buffer, checking validity. - err = compact(&e.Buffer, b, true) - } - if err != nil { - e.error(&MarshalerError{v.Type(), err}) - } - return - } - - writeString := (*encodeState).WriteString - if quoted { - writeString = (*encodeState).string - } - - switch v.Kind() { - case reflect.Bool: - x := v.Bool() - if x { - writeString(e, "true") - } else { - writeString(e, "false") - } - - case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: - b := strconv.AppendInt(e.scratch[:0], v.Int(), 10) - if quoted { - writeString(e, string(b)) - } else { - e.Write(b) - } - case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr: - b := strconv.AppendUint(e.scratch[:0], v.Uint(), 10) - if quoted { - writeString(e, string(b)) - } else { - e.Write(b) - } - case reflect.Float32, reflect.Float64: - f := v.Float() - if math.IsInf(f, 0) || math.IsNaN(f) { - e.error(&UnsupportedValueError{v, strconv.FormatFloat(f, 'g', -1, v.Type().Bits())}) - } - b := strconv.AppendFloat(e.scratch[:0], f, 'g', -1, v.Type().Bits()) - if quoted { - writeString(e, string(b)) - } else { - e.Write(b) - } - case reflect.String: - if v.Type() == numberType { - numStr := v.String() - if numStr == "" { - numStr = "0" // Number's zero-val - } - e.WriteString(numStr) - break - } - if quoted { - sb, err := Marshal(v.String()) - if err != nil { - e.error(err) - } - e.string(string(sb)) - } else { - e.string(v.String()) - } - - case reflect.Struct: - e.WriteByte('{') - first := true - for _, f := range cachedTypeFields(v.Type()) { - fv := fieldByIndex(v, f.index) - if !fv.IsValid() || f.omitEmpty && isEmptyValue(fv) { - continue - } - if first { - first = false - } else { - e.WriteByte(',') - } - e.string(f.name) - e.WriteByte(':') - e.reflectValueQuoted(fv, f.quoted) - } - e.WriteByte('}') - - case reflect.Map: - if v.Type().Key().Kind() != reflect.String { - e.error(&UnsupportedTypeError{v.Type()}) - } - if v.IsNil() { - e.WriteString("null") - break - } - e.WriteByte('{') - var sv stringValues = v.MapKeys() - sort.Sort(sv) - for i, k := range sv { - if i > 0 { - e.WriteByte(',') - } - e.string(k.String()) - e.WriteByte(':') - e.reflectValue(v.MapIndex(k)) - } - e.WriteByte('}') - - case reflect.Slice: - if v.IsNil() { - e.WriteString("null") - break - } - if v.Type().Elem().Kind() == reflect.Uint8 { - // Byte slices get special treatment; arrays don't. - s := v.Bytes() - e.WriteByte('"') - if len(s) < 1024 { - // for small buffers, using Encode directly is much faster. - dst := make([]byte, base64.StdEncoding.EncodedLen(len(s))) - base64.StdEncoding.Encode(dst, s) - e.Write(dst) - } else { - // for large buffers, avoid unnecessary extra temporary - // buffer space. - enc := base64.NewEncoder(base64.StdEncoding, e) - enc.Write(s) - enc.Close() - } - e.WriteByte('"') - break - } - // Slices can be marshalled as nil, but otherwise are handled - // as arrays. - fallthrough - case reflect.Array: - e.WriteByte('[') - n := v.Len() - for i := 0; i < n; i++ { - if i > 0 { - e.WriteByte(',') - } - e.reflectValue(v.Index(i)) - } - e.WriteByte(']') - - case reflect.Interface, reflect.Ptr: - if v.IsNil() { - e.WriteString("null") - return - } - e.reflectValue(v.Elem()) - - default: - e.error(&UnsupportedTypeError{v.Type()}) - } - return -} - -func isValidTag(s string) bool { - if s == "" { - return false - } - for _, c := range s { - switch { - case strings.ContainsRune("!#$%&()*+-./:<=>?@[]^_{|}~ ", c): - // Backslash and quote chars are reserved, but - // otherwise any punctuation chars are allowed - // in a tag name. - default: - if !unicode.IsLetter(c) && !unicode.IsDigit(c) { - return false - } - } - } - return true -} - -func fieldByIndex(v reflect.Value, index []int) reflect.Value { - for _, i := range index { - if v.Kind() == reflect.Ptr { - if v.IsNil() { - return reflect.Value{} - } - v = v.Elem() - } - v = v.Field(i) - } - return v -} - -// stringValues is a slice of reflect.Value holding *reflect.StringValue. -// It implements the methods to sort by string. -type stringValues []reflect.Value - -func (sv stringValues) Len() int { return len(sv) } -func (sv stringValues) Swap(i, j int) { sv[i], sv[j] = sv[j], sv[i] } -func (sv stringValues) Less(i, j int) bool { return sv.get(i) < sv.get(j) } -func (sv stringValues) get(i int) string { return sv[i].String() } - -func (e *encodeState) string(s string) (int, error) { - len0 := e.Len() - e.WriteByte('"') - start := 0 - for i := 0; i < len(s); { - if b := s[i]; b < utf8.RuneSelf { - if 0x20 <= b && b != '\\' && b != '"' && b != '<' && b != '>' { - i++ - continue - } - if start < i { - e.WriteString(s[start:i]) - } - switch b { - case '\\', '"': - e.WriteByte('\\') - e.WriteByte(b) - case '\n': - e.WriteByte('\\') - e.WriteByte('n') - case '\r': - e.WriteByte('\\') - e.WriteByte('r') - default: - // This encodes bytes < 0x20 except for \n and \r, - // as well as < and >. The latter are escaped because they - // can lead to security holes when user-controlled strings - // are rendered into JSON and served to some browsers. - e.WriteString(`\u00`) - e.WriteByte(hex[b>>4]) - e.WriteByte(hex[b&0xF]) - } - i++ - start = i - continue - } - c, size := utf8.DecodeRuneInString(s[i:]) - if c == utf8.RuneError && size == 1 { - e.error(&InvalidUTF8Error{s}) - } - i += size - } - if start < len(s) { - e.WriteString(s[start:]) - } - e.WriteByte('"') - return e.Len() - len0, nil -} - -// A field represents a single field found in a struct. -type field struct { - name string - tag bool - index []int - typ reflect.Type - omitEmpty bool - quoted bool -} - -// byName sorts field by name, breaking ties with depth, -// then breaking ties with "name came from json tag", then -// breaking ties with index sequence. -type byName []field - -func (x byName) Len() int { return len(x) } - -func (x byName) Swap(i, j int) { x[i], x[j] = x[j], x[i] } - -func (x byName) Less(i, j int) bool { - if x[i].name != x[j].name { - return x[i].name < x[j].name - } - if len(x[i].index) != len(x[j].index) { - return len(x[i].index) < len(x[j].index) - } - if x[i].tag != x[j].tag { - return x[i].tag - } - return byIndex(x).Less(i, j) -} - -// byIndex sorts field by index sequence. -type byIndex []field - -func (x byIndex) Len() int { return len(x) } - -func (x byIndex) Swap(i, j int) { x[i], x[j] = x[j], x[i] } - -func (x byIndex) Less(i, j int) bool { - for k, xik := range x[i].index { - if k >= len(x[j].index) { - return false - } - if xik != x[j].index[k] { - return xik < x[j].index[k] - } - } - return len(x[i].index) < len(x[j].index) -} - -// typeFields returns a list of fields that JSON should recognize for the given type. -// The algorithm is breadth-first search over the set of structs to include - the top struct -// and then any reachable anonymous structs. -func typeFields(t reflect.Type) []field { - // Anonymous fields to explore at the current level and the next. - current := []field{} - next := []field{{typ: t}} - - // Count of queued names for current level and the next. - count := map[reflect.Type]int{} - nextCount := map[reflect.Type]int{} - - // Types already visited at an earlier level. - visited := map[reflect.Type]bool{} - - // Fields found. - var fields []field - - for len(next) > 0 { - current, next = next, current[:0] - count, nextCount = nextCount, map[reflect.Type]int{} - - for _, f := range current { - if visited[f.typ] { - continue - } - visited[f.typ] = true - - // Scan f.typ for fields to include. - for i := 0; i < f.typ.NumField(); i++ { - sf := f.typ.Field(i) - if sf.PkgPath != "" { // unexported - continue - } - tag := sf.Tag.Get("json") - if tag == "-" { - continue - } - name, opts := parseTag(tag) - if !isValidTag(name) { - name = "" - } - index := make([]int, len(f.index)+1) - copy(index, f.index) - index[len(f.index)] = i - - ft := sf.Type - if ft.Name() == "" && ft.Kind() == reflect.Ptr { - // Follow pointer. - ft = ft.Elem() - } - - // Record found field and index sequence. - if name != "" || !sf.Anonymous || ft.Kind() != reflect.Struct { - tagged := name != "" - if name == "" { - name = sf.Name - } - fields = append(fields, field{name, tagged, index, ft, - opts.Contains("omitempty"), opts.Contains("string")}) - if count[f.typ] > 1 { - // If there were multiple instances, add a second, - // so that the annihilation code will see a duplicate. - // It only cares about the distinction between 1 or 2, - // so don't bother generating any more copies. - fields = append(fields, fields[len(fields)-1]) - } - continue - } - - // Record new anonymous struct to explore in next round. - nextCount[ft]++ - if nextCount[ft] == 1 { - next = append(next, field{name: ft.Name(), index: index, typ: ft}) - } - } - } - } - - sort.Sort(byName(fields)) - - // Remove fields with annihilating name collisions - // and also fields shadowed by fields with explicit JSON tags. - name := "" - out := fields[:0] - for _, f := range fields { - if f.name != name { - name = f.name - out = append(out, f) - continue - } - if n := len(out); n > 0 && out[n-1].name == name && (!out[n-1].tag || f.tag) { - out = out[:n-1] - } - } - fields = out - - sort.Sort(byIndex(fields)) - - return fields -} - -var fieldCache struct { - sync.RWMutex - m map[reflect.Type][]field -} - -// cachedTypeFields is like typeFields but uses a cache to avoid repeated work. -func cachedTypeFields(t reflect.Type) []field { - fieldCache.RLock() - f := fieldCache.m[t] - fieldCache.RUnlock() - if f != nil { - return f - } - - // Compute fields without lock. - // Might duplicate effort but won't hold other computations back. - f = typeFields(t) - if f == nil { - f = []field{} - } - - fieldCache.Lock() - if fieldCache.m == nil { - fieldCache.m = map[reflect.Type][]field{} - } - fieldCache.m[t] = f - fieldCache.Unlock() - return f -} |