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 b := strconv.AppendInt(e.scratch[:0], int64(len(s)), 10)
73 func (e *Encoder) reflectByteSlice(s []byte) {
74 b := strconv.AppendInt(e.scratch[:0], int64(len(s)), 10)
80 // Returns true if the value implements Marshaler interface and marshaling was
82 func (e *Encoder) reflectMarshaler(v reflect.Value) bool {
83 if !v.Type().Implements(marshalerType) {
84 if v.Kind() != reflect.Ptr && v.CanAddr() && v.Addr().Type().Implements(marshalerType) {
90 m := v.Interface().(Marshaler)
91 data, err := m.MarshalBencode()
93 panic(&MarshalerError{v.Type(), err})
99 var bigIntType = reflect.TypeOf((*big.Int)(nil)).Elem()
101 func (e *Encoder) reflectValue(v reflect.Value) {
103 if e.reflectMarshaler(v) {
107 if v.Type() == bigIntType {
109 bi := v.Interface().(big.Int)
110 e.writeString(bi.String())
122 case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
124 b := strconv.AppendInt(e.scratch[:0], v.Int(), 10)
127 case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
129 b := strconv.AppendUint(e.scratch[:0], v.Uint(), 10)
133 e.reflectString(v.String())
136 for _, ef := range getEncodeFields(v.Type()) {
137 fieldValue := ef.i(v)
138 if !fieldValue.IsValid() {
141 if ef.omitEmpty && isEmptyValue(fieldValue) {
144 e.reflectString(ef.tag)
145 e.reflectValue(fieldValue)
149 if v.Type().Key().Kind() != reflect.String {
150 panic(&MarshalTypeError{v.Type()})
157 sv := stringValues(v.MapKeys())
159 for _, key := range sv {
160 e.reflectString(key.String())
161 e.reflectValue(v.MapIndex(key))
167 e.reflectSlice(v.Slice(0, v.Len()))
168 case reflect.Interface:
169 e.reflectValue(v.Elem())
172 v = reflect.Zero(v.Type().Elem())
178 panic(&MarshalTypeError{v.Type()})
182 func (e *Encoder) reflectSlice(v reflect.Value) {
183 if v.Type().Elem().Kind() == reflect.Uint8 {
184 // This can panic if v is not addressable, such as by passing an array of bytes by value. We
185 // could copy them and make a slice to the copy, or the user could just avoid doing this. It
186 // remains to be seen.
188 e.reflectByteSlice(s)
196 for i, n := 0, v.Len(); i < n; i++ {
197 e.reflectValue(v.Index(i))
202 type encodeField struct {
203 i func(v reflect.Value) reflect.Value
208 type encodeFieldsSortType []encodeField
210 func (ef encodeFieldsSortType) Len() int { return len(ef) }
211 func (ef encodeFieldsSortType) Swap(i, j int) { ef[i], ef[j] = ef[j], ef[i] }
212 func (ef encodeFieldsSortType) Less(i, j int) bool { return ef[i].tag < ef[j].tag }
215 typeCacheLock sync.RWMutex
216 encodeFieldsCache = make(map[reflect.Type][]encodeField)
219 func getEncodeFields(t reflect.Type) []encodeField {
220 typeCacheLock.RLock()
221 fs, ok := encodeFieldsCache[t]
222 typeCacheLock.RUnlock()
226 fs = makeEncodeFields(t)
228 defer typeCacheLock.Unlock()
229 encodeFieldsCache[t] = fs
233 func makeEncodeFields(t reflect.Type) (fs []encodeField) {
234 for _i, n := 0, t.NumField(); _i < n; _i++ {
242 if t.Kind() == reflect.Ptr {
245 anonEFs := makeEncodeFields(t)
246 for aefi := range anonEFs {
247 anonEF := anonEFs[aefi]
248 bottomField := anonEF
249 bottomField.i = func(v reflect.Value) reflect.Value {
251 if v.Kind() == reflect.Ptr {
253 // This will skip serializing this value.
254 return reflect.Value{}
260 fs = append(fs, bottomField)
265 ef.i = func(v reflect.Value) reflect.Value {
277 ef.omitEmpty = tv.OmitEmpty()
280 fss := encodeFieldsSortType(fs)