Function mapEncodeFuncOf

proto/map.go:81–201

(t reflect.Type, f *mapField)

}

func mapEncodeFuncOf(t reflect.Type, f *mapField) encodeFunc {
	keyTag := [1]byte{}
	valTag := [1]byte{}
	encodeTag(keyTag[:], 1, f.keyCodec.wire)
	encodeTag(valTag[:], 2, f.valCodec.wire)

	number := fieldNumber(f.number)
	mapTag := make([]byte, sizeOfTag(number, varlen)+zeroSize)
	encodeTag(mapTag, number, varlen)

	zero := mapTag
	mapTag = mapTag[:len(mapTag)-1]

	return func(b []byte, p unsafe.Pointer, flags flags) (int, error) {
		if p == nil {
			return 0, nil
		}

		if !flags.has(inline) {
			p = *(*unsafe.Pointer)(p)
		}

		offset := 0
		m := MapIter{}
		defer m.Done()

		for m.Init(pointer(t), p); m.HasNext(); m.Next() {
			key := m.Key()
			val := m.Value()

			keySize := f.keyCodec.size(key, wantzero)
			valSize := f.valCodec.size(val, wantzero)
			elemSize := keySize + valSize

			if keySize > 0 {
				elemSize += len(keyTag)
				if (f.keyFlags & embedded) != 0 {
					elemSize += sizeOfVarint(uint64(keySize))
				}
			}

			if valSize > 0 {
				elemSize += len(valTag)
				if (f.valFlags & embedded) != 0 {
					elemSize += sizeOfVarint(uint64(valSize))
				}
			}

			n := copy(b[offset:], mapTag)
			offset += n
			if n < len(mapTag) {
				return offset, io.ErrShortBuffer
			}
			n, err := encodeVarint(b[offset:], uint64(elemSize))
			offset += n
			if err != nil {
				return offset, err
			}