11 "github.com/anacrolix/missinggo"
14 func isEmptyValue(v reflect.Value) bool {
15 return missinggo.IsEmptyValue(v)
22 WriteString(string) (int, error)
27 func (e *Encoder) Encode(v interface{}) (err error) {
32 if e := recover(); e != nil {
33 if _, ok := e.(runtime.Error); ok {
43 e.reflectValue(reflect.ValueOf(v))
47 type string_values []reflect.Value
49 func (sv string_values) Len() int { return len(sv) }
50 func (sv string_values) Swap(i, j int) { sv[i], sv[j] = sv[j], sv[i] }
51 func (sv string_values) Less(i, j int) bool { return sv.get(i) < sv.get(j) }
52 func (sv string_values) get(i int) string { return sv[i].String() }
54 func (e *Encoder) write(s []byte) {
55 _, err := e.w.Write(s)
61 func (e *Encoder) writeString(s string) {
62 _, err := e.w.WriteString(s)
68 func (e *Encoder) reflectString(s string) {
69 b := strconv.AppendInt(e.scratch[:0], int64(len(s)), 10)
75 func (e *Encoder) reflectByteSlice(s []byte) {
76 b := strconv.AppendInt(e.scratch[:0], int64(len(s)), 10)
82 // returns true if the value implements Marshaler interface and marshaling was
84 func (e *Encoder) reflectMarshaler(v reflect.Value) bool {
85 m, ok := v.Interface().(Marshaler)
87 // T doesn't work, try *T
88 if v.Kind() != reflect.Ptr && v.CanAddr() {
89 m, ok = v.Addr().Interface().(Marshaler)
95 if ok && (v.Kind() != reflect.Ptr || !v.IsNil()) {
96 data, err := m.MarshalBencode()
98 panic(&MarshalerError{v.Type(), err})
107 func (e *Encoder) reflectValue(v reflect.Value) {
109 if e.reflectMarshaler(v) {
120 case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
121 b := strconv.AppendInt(e.scratch[:0], v.Int(), 10)
125 case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
126 b := strconv.AppendUint(e.scratch[:0], v.Uint(), 10)
131 e.reflectString(v.String())
134 for _, ef := range encodeFields(v.Type()) {
135 field_value := v.Field(ef.i)
136 if ef.omit_empty && isEmptyValue(field_value) {
139 e.reflectString(ef.tag)
140 e.reflectValue(field_value)
144 if v.Type().Key().Kind() != reflect.String {
145 panic(&MarshalTypeError{v.Type()})
152 sv := string_values(v.MapKeys())
154 for _, key := range sv {
155 e.reflectString(key.String())
156 e.reflectValue(v.MapIndex(key))
164 if v.Type().Elem().Kind() == reflect.Uint8 {
166 e.reflectByteSlice(s)
172 for i, n := 0, v.Len(); i < n; i++ {
173 e.reflectValue(v.Index(i))
176 case reflect.Interface:
177 e.reflectValue(v.Elem())
180 v = reflect.Zero(v.Type().Elem())
186 panic(&MarshalTypeError{v.Type()})
190 type encodeField struct {
196 type encodeFieldsSortType []encodeField
198 func (ef encodeFieldsSortType) Len() int { return len(ef) }
199 func (ef encodeFieldsSortType) Swap(i, j int) { ef[i], ef[j] = ef[j], ef[i] }
200 func (ef encodeFieldsSortType) Less(i, j int) bool { return ef[i].tag < ef[j].tag }
203 typeCacheLock sync.RWMutex
204 encodeFieldsCache = make(map[reflect.Type][]encodeField)
207 func encodeFields(t reflect.Type) []encodeField {
208 typeCacheLock.RLock()
209 fs, ok := encodeFieldsCache[t]
210 typeCacheLock.RUnlock()
216 defer typeCacheLock.Unlock()
217 fs, ok = encodeFieldsCache[t]
222 for i, n := 0, t.NumField(); i < n; i++ {
234 tv := f.Tag.Get("bencode")
239 name, opts := parseTag(tv)
243 ef.omit_empty = opts.contains("omitempty")
247 fss := encodeFieldsSortType(fs)
249 encodeFieldsCache[t] = fs