| Matteo Scandolo | a428586 | 2020-12-01 18:10:10 -0800 | [diff] [blame^] | 1 | package jsoniter |
| 2 | |
| 3 | import ( |
| 4 | "fmt" |
| 5 | "github.com/modern-go/reflect2" |
| 6 | "io" |
| 7 | "unsafe" |
| 8 | ) |
| 9 | |
| 10 | func decoderOfSlice(ctx *ctx, typ reflect2.Type) ValDecoder { |
| 11 | sliceType := typ.(*reflect2.UnsafeSliceType) |
| 12 | decoder := decoderOfType(ctx.append("[sliceElem]"), sliceType.Elem()) |
| 13 | return &sliceDecoder{sliceType, decoder} |
| 14 | } |
| 15 | |
| 16 | func encoderOfSlice(ctx *ctx, typ reflect2.Type) ValEncoder { |
| 17 | sliceType := typ.(*reflect2.UnsafeSliceType) |
| 18 | encoder := encoderOfType(ctx.append("[sliceElem]"), sliceType.Elem()) |
| 19 | return &sliceEncoder{sliceType, encoder} |
| 20 | } |
| 21 | |
| 22 | type sliceEncoder struct { |
| 23 | sliceType *reflect2.UnsafeSliceType |
| 24 | elemEncoder ValEncoder |
| 25 | } |
| 26 | |
| 27 | func (encoder *sliceEncoder) Encode(ptr unsafe.Pointer, stream *Stream) { |
| 28 | if encoder.sliceType.UnsafeIsNil(ptr) { |
| 29 | stream.WriteNil() |
| 30 | return |
| 31 | } |
| 32 | length := encoder.sliceType.UnsafeLengthOf(ptr) |
| 33 | if length == 0 { |
| 34 | stream.WriteEmptyArray() |
| 35 | return |
| 36 | } |
| 37 | stream.WriteArrayStart() |
| 38 | encoder.elemEncoder.Encode(encoder.sliceType.UnsafeGetIndex(ptr, 0), stream) |
| 39 | for i := 1; i < length; i++ { |
| 40 | stream.WriteMore() |
| 41 | elemPtr := encoder.sliceType.UnsafeGetIndex(ptr, i) |
| 42 | encoder.elemEncoder.Encode(elemPtr, stream) |
| 43 | } |
| 44 | stream.WriteArrayEnd() |
| 45 | if stream.Error != nil && stream.Error != io.EOF { |
| 46 | stream.Error = fmt.Errorf("%v: %s", encoder.sliceType, stream.Error.Error()) |
| 47 | } |
| 48 | } |
| 49 | |
| 50 | func (encoder *sliceEncoder) IsEmpty(ptr unsafe.Pointer) bool { |
| 51 | return encoder.sliceType.UnsafeLengthOf(ptr) == 0 |
| 52 | } |
| 53 | |
| 54 | type sliceDecoder struct { |
| 55 | sliceType *reflect2.UnsafeSliceType |
| 56 | elemDecoder ValDecoder |
| 57 | } |
| 58 | |
| 59 | func (decoder *sliceDecoder) Decode(ptr unsafe.Pointer, iter *Iterator) { |
| 60 | decoder.doDecode(ptr, iter) |
| 61 | if iter.Error != nil && iter.Error != io.EOF { |
| 62 | iter.Error = fmt.Errorf("%v: %s", decoder.sliceType, iter.Error.Error()) |
| 63 | } |
| 64 | } |
| 65 | |
| 66 | func (decoder *sliceDecoder) doDecode(ptr unsafe.Pointer, iter *Iterator) { |
| 67 | c := iter.nextToken() |
| 68 | sliceType := decoder.sliceType |
| 69 | if c == 'n' { |
| 70 | iter.skipThreeBytes('u', 'l', 'l') |
| 71 | sliceType.UnsafeSetNil(ptr) |
| 72 | return |
| 73 | } |
| 74 | if c != '[' { |
| 75 | iter.ReportError("decode slice", "expect [ or n, but found "+string([]byte{c})) |
| 76 | return |
| 77 | } |
| 78 | c = iter.nextToken() |
| 79 | if c == ']' { |
| 80 | sliceType.UnsafeSet(ptr, sliceType.UnsafeMakeSlice(0, 0)) |
| 81 | return |
| 82 | } |
| 83 | iter.unreadByte() |
| 84 | sliceType.UnsafeGrow(ptr, 1) |
| 85 | elemPtr := sliceType.UnsafeGetIndex(ptr, 0) |
| 86 | decoder.elemDecoder.Decode(elemPtr, iter) |
| 87 | length := 1 |
| 88 | for c = iter.nextToken(); c == ','; c = iter.nextToken() { |
| 89 | idx := length |
| 90 | length += 1 |
| 91 | sliceType.UnsafeGrow(ptr, length) |
| 92 | elemPtr = sliceType.UnsafeGetIndex(ptr, idx) |
| 93 | decoder.elemDecoder.Decode(elemPtr, iter) |
| 94 | } |
| 95 | if c != ']' { |
| 96 | iter.ReportError("decode slice", "expect ], but found "+string([]byte{c})) |
| 97 | return |
| 98 | } |
| 99 | } |