12 "github.com/anacrolix/missinggo"
15 func isEmptyValue(v reflect.Value) bool {
16 return missinggo.IsEmptyValue(v)
24 func (e *Encoder) Encode(v interface{}) (err error) {
29 if e := recover(); e != nil {
30 if _, ok := e.(runtime.Error); ok {
40 e.reflectValue(reflect.ValueOf(v))
44 type stringValues []reflect.Value
46 func (sv stringValues) Len() int { return len(sv) }
47 func (sv stringValues) Swap(i, j int) { sv[i], sv[j] = sv[j], sv[i] }
48 func (sv stringValues) Less(i, j int) bool { return sv.get(i) < sv.get(j) }
49 func (sv stringValues) get(i int) string { return sv[i].String() }
51 func (e *Encoder) write(s []byte) {
52 _, err := e.w.Write(s)
58 func (e *Encoder) writeString(s string) {
60 n := copy(e.scratch[:], s)
62 e.write(e.scratch[:n])
66 func (e *Encoder) reflectString(s string) {
67 e.writeStringPrefix(int64(len(s)))
71 func (e *Encoder) writeStringPrefix(l int64) {
72 b := strconv.AppendInt(e.scratch[:0], l, 10)
77 func (e *Encoder) reflectByteSlice(s []byte) {
78 e.writeStringPrefix(int64(len(s)))
82 // Returns true if the value implements Marshaler interface and marshaling was
84 func (e *Encoder) reflectMarshaler(v reflect.Value) bool {
85 if !v.Type().Implements(marshalerType) {
86 if v.Kind() != reflect.Ptr && v.CanAddr() && v.Addr().Type().Implements(marshalerType) {
92 m := v.Interface().(Marshaler)
93 data, err := m.MarshalBencode()
95 panic(&MarshalerError{v.Type(), err})
101 var bigIntType = reflect.TypeOf((*big.Int)(nil)).Elem()
103 func (e *Encoder) reflectValue(v reflect.Value) {
104 if e.reflectMarshaler(v) {
108 if v.Type() == bigIntType {
110 bi := v.Interface().(big.Int)
111 e.writeString(bi.String())
123 case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
125 b := strconv.AppendInt(e.scratch[:0], v.Int(), 10)
128 case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
130 b := strconv.AppendUint(e.scratch[:0], v.Uint(), 10)
134 e.reflectString(v.String())
137 for _, ef := range getEncodeFields(v.Type()) {
138 fieldValue := ef.i(v)
139 if !fieldValue.IsValid() {
142 if ef.omitEmpty && isEmptyValue(fieldValue) {
145 e.reflectString(ef.tag)
146 e.reflectValue(fieldValue)
150 if v.Type().Key().Kind() != reflect.String {
151 panic(&MarshalTypeError{v.Type()})
158 sv := stringValues(v.MapKeys())
160 for _, key := range sv {
161 e.reflectString(key.String())
162 e.reflectValue(v.MapIndex(key))
165 case reflect.Slice, reflect.Array:
167 case reflect.Interface:
168 e.reflectValue(v.Elem())
171 v = reflect.Zero(v.Type().Elem())
177 panic(&MarshalTypeError{v.Type()})
181 func (e *Encoder) reflectSequence(v reflect.Value) {
182 // Use bencode string-type
183 if v.Type().Elem().Kind() == reflect.Uint8 {
184 if v.Kind() != reflect.Slice {
185 // Can't use []byte optimization
187 e.writeStringPrefix(int64(v.Len()))
188 for i := 0; i < v.Len(); i++ {
190 b[0] = byte(v.Index(i).Uint())
195 v = v.Slice(0, v.Len())
198 e.reflectByteSlice(s)
206 for i, n := 0, v.Len(); i < n; i++ {
207 e.reflectValue(v.Index(i))
212 type encodeField struct {
213 i func(v reflect.Value) reflect.Value
218 type encodeFieldsSortType []encodeField
220 func (ef encodeFieldsSortType) Len() int { return len(ef) }
221 func (ef encodeFieldsSortType) Swap(i, j int) { ef[i], ef[j] = ef[j], ef[i] }
222 func (ef encodeFieldsSortType) Less(i, j int) bool { return ef[i].tag < ef[j].tag }
225 typeCacheLock sync.RWMutex
226 encodeFieldsCache = make(map[reflect.Type][]encodeField)
229 func getEncodeFields(t reflect.Type) []encodeField {
230 typeCacheLock.RLock()
231 fs, ok := encodeFieldsCache[t]
232 typeCacheLock.RUnlock()
236 fs = makeEncodeFields(t)
238 defer typeCacheLock.Unlock()
239 encodeFieldsCache[t] = fs
243 func makeEncodeFields(t reflect.Type) (fs []encodeField) {
244 for _i, n := 0, t.NumField(); _i < n; _i++ {
252 if t.Kind() == reflect.Ptr {
255 anonEFs := makeEncodeFields(t)
256 for aefi := range anonEFs {
257 anonEF := anonEFs[aefi]
258 bottomField := anonEF
259 bottomField.i = func(v reflect.Value) reflect.Value {
261 if v.Kind() == reflect.Ptr {
263 // This will skip serializing this value.
264 return reflect.Value{}
270 fs = append(fs, bottomField)
275 ef.i = func(v reflect.Value) reflect.Value {
287 ef.omitEmpty = tv.OmitEmpty()
290 fss := encodeFieldsSortType(fs)