summaryrefslogtreecommitdiffstats
path: root/src/encoding/gob
diff options
context:
space:
mode:
Diffstat (limited to 'src/encoding/gob')
-rw-r--r--src/encoding/gob/codec_test.go1529
-rw-r--r--src/encoding/gob/debug.go706
-rw-r--r--src/encoding/gob/dec_helpers.go469
-rw-r--r--src/encoding/gob/decgen.go244
-rw-r--r--src/encoding/gob/decode.go1264
-rw-r--r--src/encoding/gob/decoder.go224
-rw-r--r--src/encoding/gob/doc.go415
-rw-r--r--src/encoding/gob/dump.go30
-rw-r--r--src/encoding/gob/enc_helpers.go414
-rw-r--r--src/encoding/gob/encgen.go221
-rw-r--r--src/encoding/gob/encode.go705
-rw-r--r--src/encoding/gob/encoder.go258
-rw-r--r--src/encoding/gob/encoder_test.go1154
-rw-r--r--src/encoding/gob/error.go42
-rw-r--r--src/encoding/gob/example_encdec_test.go61
-rw-r--r--src/encoding/gob/example_interface_test.go81
-rw-r--r--src/encoding/gob/example_test.go60
-rw-r--r--src/encoding/gob/gobencdec_test.go822
-rw-r--r--src/encoding/gob/timing_test.go314
-rw-r--r--src/encoding/gob/type.go913
-rw-r--r--src/encoding/gob/type_test.go262
21 files changed, 10188 insertions, 0 deletions
diff --git a/src/encoding/gob/codec_test.go b/src/encoding/gob/codec_test.go
new file mode 100644
index 0000000..f38e88b
--- /dev/null
+++ b/src/encoding/gob/codec_test.go
@@ -0,0 +1,1529 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gob
+
+import (
+ "bytes"
+ "errors"
+ "flag"
+ "math"
+ "math/rand"
+ "reflect"
+ "strings"
+ "testing"
+ "time"
+)
+
+var doFuzzTests = flag.Bool("gob.fuzz", false, "run the fuzz tests, which are large and very slow")
+
+// Guarantee encoding format by comparing some encodings to hand-written values
+type EncodeT struct {
+ x uint64
+ b []byte
+}
+
+var encodeT = []EncodeT{
+ {0x00, []byte{0x00}},
+ {0x0F, []byte{0x0F}},
+ {0xFF, []byte{0xFF, 0xFF}},
+ {0xFFFF, []byte{0xFE, 0xFF, 0xFF}},
+ {0xFFFFFF, []byte{0xFD, 0xFF, 0xFF, 0xFF}},
+ {0xFFFFFFFF, []byte{0xFC, 0xFF, 0xFF, 0xFF, 0xFF}},
+ {0xFFFFFFFFFF, []byte{0xFB, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF}},
+ {0xFFFFFFFFFFFF, []byte{0xFA, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF}},
+ {0xFFFFFFFFFFFFFF, []byte{0xF9, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF}},
+ {0xFFFFFFFFFFFFFFFF, []byte{0xF8, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF}},
+ {0x1111, []byte{0xFE, 0x11, 0x11}},
+ {0x1111111111111111, []byte{0xF8, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11}},
+ {0x8888888888888888, []byte{0xF8, 0x88, 0x88, 0x88, 0x88, 0x88, 0x88, 0x88, 0x88}},
+ {1 << 63, []byte{0xF8, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}},
+}
+
+// testError is meant to be used as a deferred function to turn a panic(gobError) into a
+// plain test.Error call.
+func testError(t *testing.T) {
+ if e := recover(); e != nil {
+ t.Error(e.(gobError).err) // Will re-panic if not one of our errors, such as a runtime error.
+ }
+}
+
+func newDecBuffer(data []byte) *decBuffer {
+ return &decBuffer{
+ data: data,
+ }
+}
+
+// Test basic encode/decode routines for unsigned integers
+func TestUintCodec(t *testing.T) {
+ defer testError(t)
+ b := new(encBuffer)
+ encState := newEncoderState(b)
+ for _, tt := range encodeT {
+ b.Reset()
+ encState.encodeUint(tt.x)
+ if !bytes.Equal(tt.b, b.Bytes()) {
+ t.Errorf("encodeUint: %#x encode: expected % x got % x", tt.x, tt.b, b.Bytes())
+ }
+ }
+ for u := uint64(0); ; u = (u + 1) * 7 {
+ b.Reset()
+ encState.encodeUint(u)
+ decState := newDecodeState(newDecBuffer(b.Bytes()))
+ v := decState.decodeUint()
+ if u != v {
+ t.Errorf("Encode/Decode: sent %#x received %#x", u, v)
+ }
+ if u&(1<<63) != 0 {
+ break
+ }
+ }
+}
+
+func verifyInt(i int64, t *testing.T) {
+ defer testError(t)
+ var b = new(encBuffer)
+ encState := newEncoderState(b)
+ encState.encodeInt(i)
+ decState := newDecodeState(newDecBuffer(b.Bytes()))
+ j := decState.decodeInt()
+ if i != j {
+ t.Errorf("Encode/Decode: sent %#x received %#x", uint64(i), uint64(j))
+ }
+}
+
+// Test basic encode/decode routines for signed integers
+func TestIntCodec(t *testing.T) {
+ for u := uint64(0); ; u = (u + 1) * 7 {
+ // Do positive and negative values
+ i := int64(u)
+ verifyInt(i, t)
+ verifyInt(-i, t)
+ verifyInt(^i, t)
+ if u&(1<<63) != 0 {
+ break
+ }
+ }
+ verifyInt(-1<<63, t) // a tricky case
+}
+
+// The result of encoding a true boolean with field number 7
+var boolResult = []byte{0x07, 0x01}
+
+// The result of encoding a number 17 with field number 7
+var signedResult = []byte{0x07, 2 * 17}
+var unsignedResult = []byte{0x07, 17}
+var floatResult = []byte{0x07, 0xFE, 0x31, 0x40}
+
+// The result of encoding a number 17+19i with field number 7
+var complexResult = []byte{0x07, 0xFE, 0x31, 0x40, 0xFE, 0x33, 0x40}
+
+// The result of encoding "hello" with field number 7
+var bytesResult = []byte{0x07, 0x05, 'h', 'e', 'l', 'l', 'o'}
+
+func newDecodeState(buf *decBuffer) *decoderState {
+ d := new(decoderState)
+ d.b = buf
+ return d
+}
+
+func newEncoderState(b *encBuffer) *encoderState {
+ b.Reset()
+ state := &encoderState{enc: nil, b: b}
+ state.fieldnum = -1
+ return state
+}
+
+// Test instruction execution for encoding.
+// Do not run the machine yet; instead do individual instructions crafted by hand.
+func TestScalarEncInstructions(t *testing.T) {
+ var b = new(encBuffer)
+
+ // bool
+ {
+ var data bool = true
+ instr := &encInstr{encBool, 6, nil, 0}
+ state := newEncoderState(b)
+ instr.op(instr, state, reflect.ValueOf(data))
+ if !bytes.Equal(boolResult, b.Bytes()) {
+ t.Errorf("bool enc instructions: expected % x got % x", boolResult, b.Bytes())
+ }
+ }
+
+ // int
+ {
+ b.Reset()
+ var data int = 17
+ instr := &encInstr{encInt, 6, nil, 0}
+ state := newEncoderState(b)
+ instr.op(instr, state, reflect.ValueOf(data))
+ if !bytes.Equal(signedResult, b.Bytes()) {
+ t.Errorf("int enc instructions: expected % x got % x", signedResult, b.Bytes())
+ }
+ }
+
+ // uint
+ {
+ b.Reset()
+ var data uint = 17
+ instr := &encInstr{encUint, 6, nil, 0}
+ state := newEncoderState(b)
+ instr.op(instr, state, reflect.ValueOf(data))
+ if !bytes.Equal(unsignedResult, b.Bytes()) {
+ t.Errorf("uint enc instructions: expected % x got % x", unsignedResult, b.Bytes())
+ }
+ }
+
+ // int8
+ {
+ b.Reset()
+ var data int8 = 17
+ instr := &encInstr{encInt, 6, nil, 0}
+ state := newEncoderState(b)
+ instr.op(instr, state, reflect.ValueOf(data))
+ if !bytes.Equal(signedResult, b.Bytes()) {
+ t.Errorf("int8 enc instructions: expected % x got % x", signedResult, b.Bytes())
+ }
+ }
+
+ // uint8
+ {
+ b.Reset()
+ var data uint8 = 17
+ instr := &encInstr{encUint, 6, nil, 0}
+ state := newEncoderState(b)
+ instr.op(instr, state, reflect.ValueOf(data))
+ if !bytes.Equal(unsignedResult, b.Bytes()) {
+ t.Errorf("uint8 enc instructions: expected % x got % x", unsignedResult, b.Bytes())
+ }
+ }
+
+ // int16
+ {
+ b.Reset()
+ var data int16 = 17
+ instr := &encInstr{encInt, 6, nil, 0}
+ state := newEncoderState(b)
+ instr.op(instr, state, reflect.ValueOf(data))
+ if !bytes.Equal(signedResult, b.Bytes()) {
+ t.Errorf("int16 enc instructions: expected % x got % x", signedResult, b.Bytes())
+ }
+ }
+
+ // uint16
+ {
+ b.Reset()
+ var data uint16 = 17
+ instr := &encInstr{encUint, 6, nil, 0}
+ state := newEncoderState(b)
+ instr.op(instr, state, reflect.ValueOf(data))
+ if !bytes.Equal(unsignedResult, b.Bytes()) {
+ t.Errorf("uint16 enc instructions: expected % x got % x", unsignedResult, b.Bytes())
+ }
+ }
+
+ // int32
+ {
+ b.Reset()
+ var data int32 = 17
+ instr := &encInstr{encInt, 6, nil, 0}
+ state := newEncoderState(b)
+ instr.op(instr, state, reflect.ValueOf(data))
+ if !bytes.Equal(signedResult, b.Bytes()) {
+ t.Errorf("int32 enc instructions: expected % x got % x", signedResult, b.Bytes())
+ }
+ }
+
+ // uint32
+ {
+ b.Reset()
+ var data uint32 = 17
+ instr := &encInstr{encUint, 6, nil, 0}
+ state := newEncoderState(b)
+ instr.op(instr, state, reflect.ValueOf(data))
+ if !bytes.Equal(unsignedResult, b.Bytes()) {
+ t.Errorf("uint32 enc instructions: expected % x got % x", unsignedResult, b.Bytes())
+ }
+ }
+
+ // int64
+ {
+ b.Reset()
+ var data int64 = 17
+ instr := &encInstr{encInt, 6, nil, 0}
+ state := newEncoderState(b)
+ instr.op(instr, state, reflect.ValueOf(data))
+ if !bytes.Equal(signedResult, b.Bytes()) {
+ t.Errorf("int64 enc instructions: expected % x got % x", signedResult, b.Bytes())
+ }
+ }
+
+ // uint64
+ {
+ b.Reset()
+ var data uint64 = 17
+ instr := &encInstr{encUint, 6, nil, 0}
+ state := newEncoderState(b)
+ instr.op(instr, state, reflect.ValueOf(data))
+ if !bytes.Equal(unsignedResult, b.Bytes()) {
+ t.Errorf("uint64 enc instructions: expected % x got % x", unsignedResult, b.Bytes())
+ }
+ }
+
+ // float32
+ {
+ b.Reset()
+ var data float32 = 17
+ instr := &encInstr{encFloat, 6, nil, 0}
+ state := newEncoderState(b)
+ instr.op(instr, state, reflect.ValueOf(data))
+ if !bytes.Equal(floatResult, b.Bytes()) {
+ t.Errorf("float32 enc instructions: expected % x got % x", floatResult, b.Bytes())
+ }
+ }
+
+ // float64
+ {
+ b.Reset()
+ var data float64 = 17
+ instr := &encInstr{encFloat, 6, nil, 0}
+ state := newEncoderState(b)
+ instr.op(instr, state, reflect.ValueOf(data))
+ if !bytes.Equal(floatResult, b.Bytes()) {
+ t.Errorf("float64 enc instructions: expected % x got % x", floatResult, b.Bytes())
+ }
+ }
+
+ // bytes == []uint8
+ {
+ b.Reset()
+ data := []byte("hello")
+ instr := &encInstr{encUint8Array, 6, nil, 0}
+ state := newEncoderState(b)
+ instr.op(instr, state, reflect.ValueOf(data))
+ if !bytes.Equal(bytesResult, b.Bytes()) {
+ t.Errorf("bytes enc instructions: expected % x got % x", bytesResult, b.Bytes())
+ }
+ }
+
+ // string
+ {
+ b.Reset()
+ var data string = "hello"
+ instr := &encInstr{encString, 6, nil, 0}
+ state := newEncoderState(b)
+ instr.op(instr, state, reflect.ValueOf(data))
+ if !bytes.Equal(bytesResult, b.Bytes()) {
+ t.Errorf("string enc instructions: expected % x got % x", bytesResult, b.Bytes())
+ }
+ }
+}
+
+func execDec(instr *decInstr, state *decoderState, t *testing.T, value reflect.Value) {
+ defer testError(t)
+ v := int(state.decodeUint())
+ if v+state.fieldnum != 6 {
+ t.Fatalf("decoding field number %d, got %d", 6, v+state.fieldnum)
+ }
+ instr.op(instr, state, value.Elem())
+ state.fieldnum = 6
+}
+
+func newDecodeStateFromData(data []byte) *decoderState {
+ b := newDecBuffer(data)
+ state := newDecodeState(b)
+ state.fieldnum = -1
+ return state
+}
+
+// Test instruction execution for decoding.
+// Do not run the machine yet; instead do individual instructions crafted by hand.
+func TestScalarDecInstructions(t *testing.T) {
+ ovfl := errors.New("overflow")
+
+ // bool
+ {
+ var data bool
+ instr := &decInstr{decBool, 6, nil, ovfl}
+ state := newDecodeStateFromData(boolResult)
+ execDec(instr, state, t, reflect.ValueOf(&data))
+ if data != true {
+ t.Errorf("bool a = %v not true", data)
+ }
+ }
+ // int
+ {
+ var data int
+ instr := &decInstr{decOpTable[reflect.Int], 6, nil, ovfl}
+ state := newDecodeStateFromData(signedResult)
+ execDec(instr, state, t, reflect.ValueOf(&data))
+ if data != 17 {
+ t.Errorf("int a = %v not 17", data)
+ }
+ }
+
+ // uint
+ {
+ var data uint
+ instr := &decInstr{decOpTable[reflect.Uint], 6, nil, ovfl}
+ state := newDecodeStateFromData(unsignedResult)
+ execDec(instr, state, t, reflect.ValueOf(&data))
+ if data != 17 {
+ t.Errorf("uint a = %v not 17", data)
+ }
+ }
+
+ // int8
+ {
+ var data int8
+ instr := &decInstr{decInt8, 6, nil, ovfl}
+ state := newDecodeStateFromData(signedResult)
+ execDec(instr, state, t, reflect.ValueOf(&data))
+ if data != 17 {
+ t.Errorf("int8 a = %v not 17", data)
+ }
+ }
+
+ // uint8
+ {
+ var data uint8
+ instr := &decInstr{decUint8, 6, nil, ovfl}
+ state := newDecodeStateFromData(unsignedResult)
+ execDec(instr, state, t, reflect.ValueOf(&data))
+ if data != 17 {
+ t.Errorf("uint8 a = %v not 17", data)
+ }
+ }
+
+ // int16
+ {
+ var data int16
+ instr := &decInstr{decInt16, 6, nil, ovfl}
+ state := newDecodeStateFromData(signedResult)
+ execDec(instr, state, t, reflect.ValueOf(&data))
+ if data != 17 {
+ t.Errorf("int16 a = %v not 17", data)
+ }
+ }
+
+ // uint16
+ {
+ var data uint16
+ instr := &decInstr{decUint16, 6, nil, ovfl}
+ state := newDecodeStateFromData(unsignedResult)
+ execDec(instr, state, t, reflect.ValueOf(&data))
+ if data != 17 {
+ t.Errorf("uint16 a = %v not 17", data)
+ }
+ }
+
+ // int32
+ {
+ var data int32
+ instr := &decInstr{decInt32, 6, nil, ovfl}
+ state := newDecodeStateFromData(signedResult)
+ execDec(instr, state, t, reflect.ValueOf(&data))
+ if data != 17 {
+ t.Errorf("int32 a = %v not 17", data)
+ }
+ }
+
+ // uint32
+ {
+ var data uint32
+ instr := &decInstr{decUint32, 6, nil, ovfl}
+ state := newDecodeStateFromData(unsignedResult)
+ execDec(instr, state, t, reflect.ValueOf(&data))
+ if data != 17 {
+ t.Errorf("uint32 a = %v not 17", data)
+ }
+ }
+
+ // uintptr
+ {
+ var data uintptr
+ instr := &decInstr{decOpTable[reflect.Uintptr], 6, nil, ovfl}
+ state := newDecodeStateFromData(unsignedResult)
+ execDec(instr, state, t, reflect.ValueOf(&data))
+ if data != 17 {
+ t.Errorf("uintptr a = %v not 17", data)
+ }
+ }
+
+ // int64
+ {
+ var data int64
+ instr := &decInstr{decInt64, 6, nil, ovfl}
+ state := newDecodeStateFromData(signedResult)
+ execDec(instr, state, t, reflect.ValueOf(&data))
+ if data != 17 {
+ t.Errorf("int64 a = %v not 17", data)
+ }
+ }
+
+ // uint64
+ {
+ var data uint64
+ instr := &decInstr{decUint64, 6, nil, ovfl}
+ state := newDecodeStateFromData(unsignedResult)
+ execDec(instr, state, t, reflect.ValueOf(&data))
+ if data != 17 {
+ t.Errorf("uint64 a = %v not 17", data)
+ }
+ }
+
+ // float32
+ {
+ var data float32
+ instr := &decInstr{decFloat32, 6, nil, ovfl}
+ state := newDecodeStateFromData(floatResult)
+ execDec(instr, state, t, reflect.ValueOf(&data))
+ if data != 17 {
+ t.Errorf("float32 a = %v not 17", data)
+ }
+ }
+
+ // float64
+ {
+ var data float64
+ instr := &decInstr{decFloat64, 6, nil, ovfl}
+ state := newDecodeStateFromData(floatResult)
+ execDec(instr, state, t, reflect.ValueOf(&data))
+ if data != 17 {
+ t.Errorf("float64 a = %v not 17", data)
+ }
+ }
+
+ // complex64
+ {
+ var data complex64
+ instr := &decInstr{decOpTable[reflect.Complex64], 6, nil, ovfl}
+ state := newDecodeStateFromData(complexResult)
+ execDec(instr, state, t, reflect.ValueOf(&data))
+ if data != 17+19i {
+ t.Errorf("complex a = %v not 17+19i", data)
+ }
+ }
+
+ // complex128
+ {
+ var data complex128
+ instr := &decInstr{decOpTable[reflect.Complex128], 6, nil, ovfl}
+ state := newDecodeStateFromData(complexResult)
+ execDec(instr, state, t, reflect.ValueOf(&data))
+ if data != 17+19i {
+ t.Errorf("complex a = %v not 17+19i", data)
+ }
+ }
+
+ // bytes == []uint8
+ {
+ var data []byte
+ instr := &decInstr{decUint8Slice, 6, nil, ovfl}
+ state := newDecodeStateFromData(bytesResult)
+ execDec(instr, state, t, reflect.ValueOf(&data))
+ if string(data) != "hello" {
+ t.Errorf(`bytes a = %q not "hello"`, string(data))
+ }
+ }
+
+ // string
+ {
+ var data string
+ instr := &decInstr{decString, 6, nil, ovfl}
+ state := newDecodeStateFromData(bytesResult)
+ execDec(instr, state, t, reflect.ValueOf(&data))
+ if data != "hello" {
+ t.Errorf(`bytes a = %q not "hello"`, data)
+ }
+ }
+}
+
+func TestEndToEnd(t *testing.T) {
+ type T2 struct {
+ T string
+ }
+ type T3 struct {
+ X float64
+ Z *int
+ }
+ type T1 struct {
+ A, B, C int
+ M map[string]*float64
+ M2 map[int]T3
+ Mstring map[string]string
+ Mintptr map[int]*int
+ Mcomp map[complex128]complex128
+ Marr map[[2]string][2]*float64
+ EmptyMap map[string]int // to check that we receive a non-nil map.
+ N *[3]float64
+ Strs *[2]string
+ Int64s *[]int64
+ RI complex64
+ S string
+ Y []byte
+ T *T2
+ }
+ pi := 3.14159
+ e := 2.71828
+ two := 2.0
+ meaning := 42
+ fingers := 5
+ s1 := "string1"
+ s2 := "string2"
+ var comp1 complex128 = complex(1.0, 1.0)
+ var comp2 complex128 = complex(1.0, 1.0)
+ var arr1 [2]string
+ arr1[0] = s1
+ arr1[1] = s2
+ var arr2 [2]string
+ arr2[0] = s2
+ arr2[1] = s1
+ var floatArr1 [2]*float64
+ floatArr1[0] = &pi
+ floatArr1[1] = &e
+ var floatArr2 [2]*float64
+ floatArr2[0] = &e
+ floatArr2[1] = &two
+ t1 := &T1{
+ A: 17,
+ B: 18,
+ C: -5,
+ M: map[string]*float64{"pi": &pi, "e": &e},
+ M2: map[int]T3{4: {X: pi, Z: &meaning}, 10: {X: e, Z: &fingers}},
+ Mstring: map[string]string{"pi": "3.14", "e": "2.71"},
+ Mintptr: map[int]*int{meaning: &fingers, fingers: &meaning},
+ Mcomp: map[complex128]complex128{comp1: comp2, comp2: comp1},
+ Marr: map[[2]string][2]*float64{arr1: floatArr1, arr2: floatArr2},
+ EmptyMap: make(map[string]int),
+ N: &[3]float64{1.5, 2.5, 3.5},
+ Strs: &[2]string{s1, s2},
+ Int64s: &[]int64{77, 89, 123412342134},
+ RI: 17 - 23i,
+ S: "Now is the time",
+ Y: []byte("hello, sailor"),
+ T: &T2{"this is T2"},
+ }
+ b := new(bytes.Buffer)
+ err := NewEncoder(b).Encode(t1)
+ if err != nil {
+ t.Error("encode:", err)
+ }
+ var _t1 T1
+ err = NewDecoder(b).Decode(&_t1)
+ if err != nil {
+ t.Fatal("decode:", err)
+ }
+ if !reflect.DeepEqual(t1, &_t1) {
+ t.Errorf("encode expected %v got %v", *t1, _t1)
+ }
+ // Be absolutely sure the received map is non-nil.
+ if t1.EmptyMap == nil {
+ t.Errorf("nil map sent")
+ }
+ if _t1.EmptyMap == nil {
+ t.Errorf("nil map received")
+ }
+}
+
+func TestOverflow(t *testing.T) {
+ type inputT struct {
+ Maxi int64
+ Mini int64
+ Maxu uint64
+ Maxf float64
+ Minf float64
+ Maxc complex128
+ Minc complex128
+ }
+ var it inputT
+ var err error
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ dec := NewDecoder(b)
+
+ // int8
+ b.Reset()
+ it = inputT{
+ Maxi: math.MaxInt8 + 1,
+ }
+ type outi8 struct {
+ Maxi int8
+ Mini int8
+ }
+ var o1 outi8
+ enc.Encode(it)
+ err = dec.Decode(&o1)
+ if err == nil || err.Error() != `value for "Maxi" out of range` {
+ t.Error("wrong overflow error for int8:", err)
+ }
+ it = inputT{
+ Mini: math.MinInt8 - 1,
+ }
+ b.Reset()
+ enc.Encode(it)
+ err = dec.Decode(&o1)
+ if err == nil || err.Error() != `value for "Mini" out of range` {
+ t.Error("wrong underflow error for int8:", err)
+ }
+
+ // int16
+ b.Reset()
+ it = inputT{
+ Maxi: math.MaxInt16 + 1,
+ }
+ type outi16 struct {
+ Maxi int16
+ Mini int16
+ }
+ var o2 outi16
+ enc.Encode(it)
+ err = dec.Decode(&o2)
+ if err == nil || err.Error() != `value for "Maxi" out of range` {
+ t.Error("wrong overflow error for int16:", err)
+ }
+ it = inputT{
+ Mini: math.MinInt16 - 1,
+ }
+ b.Reset()
+ enc.Encode(it)
+ err = dec.Decode(&o2)
+ if err == nil || err.Error() != `value for "Mini" out of range` {
+ t.Error("wrong underflow error for int16:", err)
+ }
+
+ // int32
+ b.Reset()
+ it = inputT{
+ Maxi: math.MaxInt32 + 1,
+ }
+ type outi32 struct {
+ Maxi int32
+ Mini int32
+ }
+ var o3 outi32
+ enc.Encode(it)
+ err = dec.Decode(&o3)
+ if err == nil || err.Error() != `value for "Maxi" out of range` {
+ t.Error("wrong overflow error for int32:", err)
+ }
+ it = inputT{
+ Mini: math.MinInt32 - 1,
+ }
+ b.Reset()
+ enc.Encode(it)
+ err = dec.Decode(&o3)
+ if err == nil || err.Error() != `value for "Mini" out of range` {
+ t.Error("wrong underflow error for int32:", err)
+ }
+
+ // uint8
+ b.Reset()
+ it = inputT{
+ Maxu: math.MaxUint8 + 1,
+ }
+ type outu8 struct {
+ Maxu uint8
+ }
+ var o4 outu8
+ enc.Encode(it)
+ err = dec.Decode(&o4)
+ if err == nil || err.Error() != `value for "Maxu" out of range` {
+ t.Error("wrong overflow error for uint8:", err)
+ }
+
+ // uint16
+ b.Reset()
+ it = inputT{
+ Maxu: math.MaxUint16 + 1,
+ }
+ type outu16 struct {
+ Maxu uint16
+ }
+ var o5 outu16
+ enc.Encode(it)
+ err = dec.Decode(&o5)
+ if err == nil || err.Error() != `value for "Maxu" out of range` {
+ t.Error("wrong overflow error for uint16:", err)
+ }
+
+ // uint32
+ b.Reset()
+ it = inputT{
+ Maxu: math.MaxUint32 + 1,
+ }
+ type outu32 struct {
+ Maxu uint32
+ }
+ var o6 outu32
+ enc.Encode(it)
+ err = dec.Decode(&o6)
+ if err == nil || err.Error() != `value for "Maxu" out of range` {
+ t.Error("wrong overflow error for uint32:", err)
+ }
+
+ // float32
+ b.Reset()
+ it = inputT{
+ Maxf: math.MaxFloat32 * 2,
+ }
+ type outf32 struct {
+ Maxf float32
+ Minf float32
+ }
+ var o7 outf32
+ enc.Encode(it)
+ err = dec.Decode(&o7)
+ if err == nil || err.Error() != `value for "Maxf" out of range` {
+ t.Error("wrong overflow error for float32:", err)
+ }
+
+ // complex64
+ b.Reset()
+ it = inputT{
+ Maxc: complex(math.MaxFloat32*2, math.MaxFloat32*2),
+ }
+ type outc64 struct {
+ Maxc complex64
+ Minc complex64
+ }
+ var o8 outc64
+ enc.Encode(it)
+ err = dec.Decode(&o8)
+ if err == nil || err.Error() != `value for "Maxc" out of range` {
+ t.Error("wrong overflow error for complex64:", err)
+ }
+}
+
+func TestNesting(t *testing.T) {
+ type RT struct {
+ A string
+ Next *RT
+ }
+ rt := new(RT)
+ rt.A = "level1"
+ rt.Next = new(RT)
+ rt.Next.A = "level2"
+ b := new(bytes.Buffer)
+ NewEncoder(b).Encode(rt)
+ var drt RT
+ dec := NewDecoder(b)
+ err := dec.Decode(&drt)
+ if err != nil {
+ t.Fatal("decoder error:", err)
+ }
+ if drt.A != rt.A {
+ t.Errorf("nesting: encode expected %v got %v", *rt, drt)
+ }
+ if drt.Next == nil {
+ t.Errorf("nesting: recursion failed")
+ }
+ if drt.Next.A != rt.Next.A {
+ t.Errorf("nesting: encode expected %v got %v", *rt.Next, *drt.Next)
+ }
+}
+
+// These three structures have the same data with different indirections
+type T0 struct {
+ A int
+ B int
+ C int
+ D int
+}
+type T1 struct {
+ A int
+ B *int
+ C **int
+ D ***int
+}
+type T2 struct {
+ A ***int
+ B **int
+ C *int
+ D int
+}
+
+func TestAutoIndirection(t *testing.T) {
+ // First transfer t1 into t0
+ var t1 T1
+ t1.A = 17
+ t1.B = new(int)
+ *t1.B = 177
+ t1.C = new(*int)
+ *t1.C = new(int)
+ **t1.C = 1777
+ t1.D = new(**int)
+ *t1.D = new(*int)
+ **t1.D = new(int)
+ ***t1.D = 17777
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ enc.Encode(t1)
+ dec := NewDecoder(b)
+ var t0 T0
+ dec.Decode(&t0)
+ if t0.A != 17 || t0.B != 177 || t0.C != 1777 || t0.D != 17777 {
+ t.Errorf("t1->t0: expected {17 177 1777 17777}; got %v", t0)
+ }
+
+ // Now transfer t2 into t0
+ var t2 T2
+ t2.D = 17777
+ t2.C = new(int)
+ *t2.C = 1777
+ t2.B = new(*int)
+ *t2.B = new(int)
+ **t2.B = 177
+ t2.A = new(**int)
+ *t2.A = new(*int)
+ **t2.A = new(int)
+ ***t2.A = 17
+ b.Reset()
+ enc.Encode(t2)
+ t0 = T0{}
+ dec.Decode(&t0)
+ if t0.A != 17 || t0.B != 177 || t0.C != 1777 || t0.D != 17777 {
+ t.Errorf("t2->t0 expected {17 177 1777 17777}; got %v", t0)
+ }
+
+ // Now transfer t0 into t1
+ t0 = T0{17, 177, 1777, 17777}
+ b.Reset()
+ enc.Encode(t0)
+ t1 = T1{}
+ dec.Decode(&t1)
+ if t1.A != 17 || *t1.B != 177 || **t1.C != 1777 || ***t1.D != 17777 {
+ t.Errorf("t0->t1 expected {17 177 1777 17777}; got {%d %d %d %d}", t1.A, *t1.B, **t1.C, ***t1.D)
+ }
+
+ // Now transfer t0 into t2
+ b.Reset()
+ enc.Encode(t0)
+ t2 = T2{}
+ dec.Decode(&t2)
+ if ***t2.A != 17 || **t2.B != 177 || *t2.C != 1777 || t2.D != 17777 {
+ t.Errorf("t0->t2 expected {17 177 1777 17777}; got {%d %d %d %d}", ***t2.A, **t2.B, *t2.C, t2.D)
+ }
+
+ // Now do t2 again but without pre-allocated pointers.
+ b.Reset()
+ enc.Encode(t0)
+ ***t2.A = 0
+ **t2.B = 0
+ *t2.C = 0
+ t2.D = 0
+ dec.Decode(&t2)
+ if ***t2.A != 17 || **t2.B != 177 || *t2.C != 1777 || t2.D != 17777 {
+ t.Errorf("t0->t2 expected {17 177 1777 17777}; got {%d %d %d %d}", ***t2.A, **t2.B, *t2.C, t2.D)
+ }
+}
+
+type RT0 struct {
+ A int
+ B string
+ C float64
+}
+type RT1 struct {
+ C float64
+ B string
+ A int
+ NotSet string
+}
+
+func TestReorderedFields(t *testing.T) {
+ var rt0 RT0
+ rt0.A = 17
+ rt0.B = "hello"
+ rt0.C = 3.14159
+ b := new(bytes.Buffer)
+ NewEncoder(b).Encode(rt0)
+ dec := NewDecoder(b)
+ var rt1 RT1
+ // Wire type is RT0, local type is RT1.
+ err := dec.Decode(&rt1)
+ if err != nil {
+ t.Fatal("decode error:", err)
+ }
+ if rt0.A != rt1.A || rt0.B != rt1.B || rt0.C != rt1.C {
+ t.Errorf("rt1->rt0: expected %v; got %v", rt0, rt1)
+ }
+}
+
+// Like an RT0 but with fields we'll ignore on the decode side.
+type IT0 struct {
+ A int64
+ B string
+ Ignore_d []int
+ Ignore_e [3]float64
+ Ignore_f bool
+ Ignore_g string
+ Ignore_h []byte
+ Ignore_i *RT1
+ Ignore_m map[string]int
+ C float64
+}
+
+func TestIgnoredFields(t *testing.T) {
+ var it0 IT0
+ it0.A = 17
+ it0.B = "hello"
+ it0.C = 3.14159
+ it0.Ignore_d = []int{1, 2, 3}
+ it0.Ignore_e[0] = 1.0
+ it0.Ignore_e[1] = 2.0
+ it0.Ignore_e[2] = 3.0
+ it0.Ignore_f = true
+ it0.Ignore_g = "pay no attention"
+ it0.Ignore_h = []byte("to the curtain")
+ it0.Ignore_i = &RT1{3.1, "hi", 7, "hello"}
+ it0.Ignore_m = map[string]int{"one": 1, "two": 2}
+
+ b := new(bytes.Buffer)
+ NewEncoder(b).Encode(it0)
+ dec := NewDecoder(b)
+ var rt1 RT1
+ // Wire type is IT0, local type is RT1.
+ err := dec.Decode(&rt1)
+ if err != nil {
+ t.Error("error: ", err)
+ }
+ if int(it0.A) != rt1.A || it0.B != rt1.B || it0.C != rt1.C {
+ t.Errorf("rt0->rt1: expected %v; got %v", it0, rt1)
+ }
+}
+
+func TestBadRecursiveType(t *testing.T) {
+ type Rec ***Rec
+ var rec Rec
+ b := new(bytes.Buffer)
+ err := NewEncoder(b).Encode(&rec)
+ if err == nil {
+ t.Error("expected error; got none")
+ } else if !strings.Contains(err.Error(), "recursive") {
+ t.Error("expected recursive type error; got", err)
+ }
+ // Can't test decode easily because we can't encode one, so we can't pass one to a Decoder.
+}
+
+type Indirect struct {
+ A ***[3]int
+ S ***[]int
+ M ****map[string]int
+}
+
+type Direct struct {
+ A [3]int
+ S []int
+ M map[string]int
+}
+
+func TestIndirectSliceMapArray(t *testing.T) {
+ // Marshal indirect, unmarshal to direct.
+ i := new(Indirect)
+ i.A = new(**[3]int)
+ *i.A = new(*[3]int)
+ **i.A = new([3]int)
+ ***i.A = [3]int{1, 2, 3}
+ i.S = new(**[]int)
+ *i.S = new(*[]int)
+ **i.S = new([]int)
+ ***i.S = []int{4, 5, 6}
+ i.M = new(***map[string]int)
+ *i.M = new(**map[string]int)
+ **i.M = new(*map[string]int)
+ ***i.M = new(map[string]int)
+ ****i.M = map[string]int{"one": 1, "two": 2, "three": 3}
+ b := new(bytes.Buffer)
+ NewEncoder(b).Encode(i)
+ dec := NewDecoder(b)
+ var d Direct
+ err := dec.Decode(&d)
+ if err != nil {
+ t.Error("error: ", err)
+ }
+ if len(d.A) != 3 || d.A[0] != 1 || d.A[1] != 2 || d.A[2] != 3 {
+ t.Errorf("indirect to direct: d.A is %v not %v", d.A, ***i.A)
+ }
+ if len(d.S) != 3 || d.S[0] != 4 || d.S[1] != 5 || d.S[2] != 6 {
+ t.Errorf("indirect to direct: d.S is %v not %v", d.S, ***i.S)
+ }
+ if len(d.M) != 3 || d.M["one"] != 1 || d.M["two"] != 2 || d.M["three"] != 3 {
+ t.Errorf("indirect to direct: d.M is %v not %v", d.M, ***i.M)
+ }
+ // Marshal direct, unmarshal to indirect.
+ d.A = [3]int{11, 22, 33}
+ d.S = []int{44, 55, 66}
+ d.M = map[string]int{"four": 4, "five": 5, "six": 6}
+ i = new(Indirect)
+ b.Reset()
+ NewEncoder(b).Encode(d)
+ dec = NewDecoder(b)
+ err = dec.Decode(&i)
+ if err != nil {
+ t.Fatal("error: ", err)
+ }
+ if len(***i.A) != 3 || (***i.A)[0] != 11 || (***i.A)[1] != 22 || (***i.A)[2] != 33 {
+ t.Errorf("direct to indirect: ***i.A is %v not %v", ***i.A, d.A)
+ }
+ if len(***i.S) != 3 || (***i.S)[0] != 44 || (***i.S)[1] != 55 || (***i.S)[2] != 66 {
+ t.Errorf("direct to indirect: ***i.S is %v not %v", ***i.S, ***i.S)
+ }
+ if len(****i.M) != 3 || (****i.M)["four"] != 4 || (****i.M)["five"] != 5 || (****i.M)["six"] != 6 {
+ t.Errorf("direct to indirect: ****i.M is %v not %v", ****i.M, d.M)
+ }
+}
+
+// An interface with several implementations
+type Squarer interface {
+ Square() int
+}
+
+type Int int
+
+func (i Int) Square() int {
+ return int(i * i)
+}
+
+type Float float64
+
+func (f Float) Square() int {
+ return int(f * f)
+}
+
+type Vector []int
+
+func (v Vector) Square() int {
+ sum := 0
+ for _, x := range v {
+ sum += x * x
+ }
+ return sum
+}
+
+type Point struct {
+ X, Y int
+}
+
+func (p Point) Square() int {
+ return p.X*p.X + p.Y*p.Y
+}
+
+// A struct with interfaces in it.
+type InterfaceItem struct {
+ I int
+ Sq1, Sq2, Sq3 Squarer
+ F float64
+ Sq []Squarer
+}
+
+// The same struct without interfaces
+type NoInterfaceItem struct {
+ I int
+ F float64
+}
+
+func TestInterface(t *testing.T) {
+ iVal := Int(3)
+ fVal := Float(5)
+ // Sending a Vector will require that the receiver define a type in the middle of
+ // receiving the value for item2.
+ vVal := Vector{1, 2, 3}
+ b := new(bytes.Buffer)
+ item1 := &InterfaceItem{1, iVal, fVal, vVal, 11.5, []Squarer{iVal, fVal, nil, vVal}}
+ // Register the types.
+ Register(Int(0))
+ Register(Float(0))
+ Register(Vector{})
+ err := NewEncoder(b).Encode(item1)
+ if err != nil {
+ t.Error("expected no encode error; got", err)
+ }
+
+ item2 := InterfaceItem{}
+ err = NewDecoder(b).Decode(&item2)
+ if err != nil {
+ t.Fatal("decode:", err)
+ }
+ if item2.I != item1.I {
+ t.Error("normal int did not decode correctly")
+ }
+ if item2.Sq1 == nil || item2.Sq1.Square() != iVal.Square() {
+ t.Error("Int did not decode correctly")
+ }
+ if item2.Sq2 == nil || item2.Sq2.Square() != fVal.Square() {
+ t.Error("Float did not decode correctly")
+ }
+ if item2.Sq3 == nil || item2.Sq3.Square() != vVal.Square() {
+ t.Error("Vector did not decode correctly")
+ }
+ if item2.F != item1.F {
+ t.Error("normal float did not decode correctly")
+ }
+ // Now check that we received a slice of Squarers correctly, including a nil element
+ if len(item1.Sq) != len(item2.Sq) {
+ t.Fatalf("[]Squarer length wrong: got %d; expected %d", len(item2.Sq), len(item1.Sq))
+ }
+ for i, v1 := range item1.Sq {
+ v2 := item2.Sq[i]
+ if v1 == nil || v2 == nil {
+ if v1 != nil || v2 != nil {
+ t.Errorf("item %d inconsistent nils", i)
+ }
+ } else if v1.Square() != v2.Square() {
+ t.Errorf("item %d inconsistent values: %v %v", i, v1, v2)
+ }
+ }
+}
+
+// A struct with all basic types, stored in interfaces.
+type BasicInterfaceItem struct {
+ Int, Int8, Int16, Int32, Int64 interface{}
+ Uint, Uint8, Uint16, Uint32, Uint64 interface{}
+ Float32, Float64 interface{}
+ Complex64, Complex128 interface{}
+ Bool interface{}
+ String interface{}
+ Bytes interface{}
+}
+
+func TestInterfaceBasic(t *testing.T) {
+ b := new(bytes.Buffer)
+ item1 := &BasicInterfaceItem{
+ int(1), int8(1), int16(1), int32(1), int64(1),
+ uint(1), uint8(1), uint16(1), uint32(1), uint64(1),
+ float32(1), 1.0,
+ complex64(1i), complex128(1i),
+ true,
+ "hello",
+ []byte("sailor"),
+ }
+ err := NewEncoder(b).Encode(item1)
+ if err != nil {
+ t.Error("expected no encode error; got", err)
+ }
+
+ item2 := &BasicInterfaceItem{}
+ err = NewDecoder(b).Decode(&item2)
+ if err != nil {
+ t.Fatal("decode:", err)
+ }
+ if !reflect.DeepEqual(item1, item2) {
+ t.Errorf("encode expected %v got %v", item1, item2)
+ }
+ // Hand check a couple for correct types.
+ if v, ok := item2.Bool.(bool); !ok || !v {
+ t.Error("boolean should be true")
+ }
+ if v, ok := item2.String.(string); !ok || v != item1.String.(string) {
+ t.Errorf("string should be %v is %v", item1.String, v)
+ }
+}
+
+type String string
+
+type PtrInterfaceItem struct {
+ Str1 interface{} // basic
+ Str2 interface{} // derived
+}
+
+// We'll send pointers; should receive values.
+// Also check that we can register T but send *T.
+func TestInterfacePointer(t *testing.T) {
+ b := new(bytes.Buffer)
+ str1 := "howdy"
+ str2 := String("kiddo")
+ item1 := &PtrInterfaceItem{
+ &str1,
+ &str2,
+ }
+ // Register the type.
+ Register(str2)
+ err := NewEncoder(b).Encode(item1)
+ if err != nil {
+ t.Error("expected no encode error; got", err)
+ }
+
+ item2 := &PtrInterfaceItem{}
+ err = NewDecoder(b).Decode(&item2)
+ if err != nil {
+ t.Fatal("decode:", err)
+ }
+ // Hand test for correct types and values.
+ if v, ok := item2.Str1.(string); !ok || v != str1 {
+ t.Errorf("basic string failed: %q should be %q", v, str1)
+ }
+ if v, ok := item2.Str2.(String); !ok || v != str2 {
+ t.Errorf("derived type String failed: %q should be %q", v, str2)
+ }
+}
+
+func TestIgnoreInterface(t *testing.T) {
+ iVal := Int(3)
+ fVal := Float(5)
+ // Sending a Point will require that the receiver define a type in the middle of
+ // receiving the value for item2.
+ pVal := Point{2, 3}
+ b := new(bytes.Buffer)
+ item1 := &InterfaceItem{1, iVal, fVal, pVal, 11.5, nil}
+ // Register the types.
+ Register(Int(0))
+ Register(Float(0))
+ Register(Point{})
+ err := NewEncoder(b).Encode(item1)
+ if err != nil {
+ t.Error("expected no encode error; got", err)
+ }
+
+ item2 := NoInterfaceItem{}
+ err = NewDecoder(b).Decode(&item2)
+ if err != nil {
+ t.Fatal("decode:", err)
+ }
+ if item2.I != item1.I {
+ t.Error("normal int did not decode correctly")
+ }
+ if item2.F != item1.F {
+ t.Error("normal float did not decode correctly")
+ }
+}
+
+type U struct {
+ A int
+ B string
+ c float64
+ D uint
+}
+
+func TestUnexportedFields(t *testing.T) {
+ var u0 U
+ u0.A = 17
+ u0.B = "hello"
+ u0.c = 3.14159
+ u0.D = 23
+ b := new(bytes.Buffer)
+ NewEncoder(b).Encode(u0)
+ dec := NewDecoder(b)
+ var u1 U
+ u1.c = 1234.
+ err := dec.Decode(&u1)
+ if err != nil {
+ t.Fatal("decode error:", err)
+ }
+ if u0.A != u1.A || u0.B != u1.B || u0.D != u1.D {
+ t.Errorf("u1->u0: expected %v; got %v", u0, u1)
+ }
+ if u1.c != 1234. {
+ t.Error("u1.c modified")
+ }
+}
+
+var singletons = []interface{}{
+ true,
+ 7,
+ uint(10),
+ 3.2,
+ "hello",
+ [3]int{11, 22, 33},
+ []float32{0.5, 0.25, 0.125},
+ map[string]int{"one": 1, "two": 2},
+}
+
+func TestDebugSingleton(t *testing.T) {
+ if debugFunc == nil {
+ return
+ }
+ b := new(bytes.Buffer)
+ // Accumulate a number of values and print them out all at once.
+ for _, x := range singletons {
+ err := NewEncoder(b).Encode(x)
+ if err != nil {
+ t.Fatal("encode:", err)
+ }
+ }
+ debugFunc(b)
+}
+
+// A type that won't be defined in the gob until we send it in an interface value.
+type OnTheFly struct {
+ A int
+}
+
+type DT struct {
+ // X OnTheFly
+ A int
+ B string
+ C float64
+ I interface{}
+ J interface{}
+ I_nil interface{}
+ M map[string]int
+ T [3]int
+ S []string
+}
+
+func newDT() DT {
+ var dt DT
+ dt.A = 17
+ dt.B = "hello"
+ dt.C = 3.14159
+ dt.I = 271828
+ dt.J = OnTheFly{3}
+ dt.I_nil = nil
+ dt.M = map[string]int{"one": 1, "two": 2}
+ dt.T = [3]int{11, 22, 33}
+ dt.S = []string{"hi", "joe"}
+ return dt
+}
+
+func TestDebugStruct(t *testing.T) {
+ if debugFunc == nil {
+ return
+ }
+ Register(OnTheFly{})
+ dt := newDT()
+ b := new(bytes.Buffer)
+ err := NewEncoder(b).Encode(dt)
+ if err != nil {
+ t.Fatal("encode:", err)
+ }
+ debugBuffer := bytes.NewBuffer(b.Bytes())
+ dt2 := &DT{}
+ err = NewDecoder(b).Decode(&dt2)
+ if err != nil {
+ t.Error("decode:", err)
+ }
+ debugFunc(debugBuffer)
+}
+
+func encFuzzDec(rng *rand.Rand, in interface{}) error {
+ buf := new(bytes.Buffer)
+ enc := NewEncoder(buf)
+ if err := enc.Encode(&in); err != nil {
+ return err
+ }
+
+ b := buf.Bytes()
+ for i, bi := range b {
+ if rng.Intn(10) < 3 {
+ b[i] = bi + uint8(rng.Intn(256))
+ }
+ }
+
+ dec := NewDecoder(buf)
+ var e interface{}
+ if err := dec.Decode(&e); err != nil {
+ return err
+ }
+ return nil
+}
+
+// This does some "fuzz testing" by attempting to decode a sequence of random bytes.
+func TestFuzz(t *testing.T) {
+ if !*doFuzzTests {
+ t.Skipf("disabled; run with -gob.fuzz to enable")
+ }
+
+ // all possible inputs
+ input := []interface{}{
+ new(int),
+ new(float32),
+ new(float64),
+ new(complex128),
+ &ByteStruct{255},
+ &ArrayStruct{},
+ &StringStruct{"hello"},
+ &GobTest1{0, &StringStruct{"hello"}},
+ }
+ testFuzz(t, time.Now().UnixNano(), 100, input...)
+}
+
+func TestFuzzRegressions(t *testing.T) {
+ if !*doFuzzTests {
+ t.Skipf("disabled; run with -gob.fuzz to enable")
+ }
+
+ // An instance triggering a type name of length ~102 GB.
+ testFuzz(t, 1328492090837718000, 100, new(float32))
+ // An instance triggering a type name of 1.6 GB.
+ // Note: can take several minutes to run.
+ testFuzz(t, 1330522872628565000, 100, new(int))
+}
+
+func testFuzz(t *testing.T, seed int64, n int, input ...interface{}) {
+ for _, e := range input {
+ t.Logf("seed=%d n=%d e=%T", seed, n, e)
+ rng := rand.New(rand.NewSource(seed))
+ for i := 0; i < n; i++ {
+ encFuzzDec(rng, e)
+ }
+ }
+}
+
+// TestFuzzOneByte tries to decode corrupted input sequences
+// and checks that no panic occurs.
+func TestFuzzOneByte(t *testing.T) {
+ if !*doFuzzTests {
+ t.Skipf("disabled; run with -gob.fuzz to enable")
+ }
+
+ buf := new(bytes.Buffer)
+ Register(OnTheFly{})
+ dt := newDT()
+ if err := NewEncoder(buf).Encode(dt); err != nil {
+ t.Fatal(err)
+ }
+ s := buf.String()
+
+ indices := make([]int, 0, len(s))
+ for i := 0; i < len(s); i++ {
+ switch i {
+ case 14, 167, 231, 265: // a slice length, corruptions are not handled yet.
+ continue
+ case 248:
+ // Large map size, which currently causes an out of memory panic.
+ // See golang.org/issue/24308 and golang.org/issue/20221.
+ continue
+ }
+ indices = append(indices, i)
+ }
+ if testing.Short() {
+ indices = []int{1, 111, 178} // known fixed panics
+ }
+ for _, i := range indices {
+ for j := 0; j < 256; j += 3 {
+ b := []byte(s)
+ b[i] ^= byte(j)
+ var e DT
+ func() {
+ defer func() {
+ if p := recover(); p != nil {
+ t.Errorf("crash for b[%d] ^= 0x%x", i, j)
+ panic(p)
+ }
+ }()
+ err := NewDecoder(bytes.NewReader(b)).Decode(&e)
+ _ = err
+ }()
+ }
+ }
+}
+
+// Don't crash, just give error with invalid type id.
+// Issue 9649.
+func TestErrorInvalidTypeId(t *testing.T) {
+ data := []byte{0x01, 0x00, 0x01, 0x00}
+ d := NewDecoder(bytes.NewReader(data))
+ // When running d.Decode(&foo) the first time the decoder stops
+ // after []byte{0x01, 0x00} and reports an errBadType. Running
+ // d.Decode(&foo) again on exactly the same input sequence should
+ // give another errBadType, but instead caused a panic because
+ // decoderMap wasn't cleaned up properly after the first error.
+ for i := 0; i < 2; i++ {
+ var foo struct{}
+ err := d.Decode(&foo)
+ if err != errBadType {
+ t.Fatalf("decode: expected %s, got %s", errBadType, err)
+ }
+ }
+}
diff --git a/src/encoding/gob/debug.go b/src/encoding/gob/debug.go
new file mode 100644
index 0000000..5965fea
--- /dev/null
+++ b/src/encoding/gob/debug.go
@@ -0,0 +1,706 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Delete the next line to include in the gob package.
+//go:build ignore
+// +build ignore
+
+package gob
+
+// This file is not normally included in the gob package. Used only for debugging the package itself.
+// Except for reading uints, it is an implementation of a reader that is independent of
+// the one implemented by Decoder.
+// To enable the Debug function, delete the +build ignore line above and do
+// go install
+
+import (
+ "bytes"
+ "fmt"
+ "io"
+ "os"
+ "strings"
+ "sync"
+)
+
+var dumpBytes = false // If true, print the remaining bytes in the input buffer at each item.
+
+// Init installs the debugging facility. If this file is not compiled in the
+// package, the tests in codec_test.go are no-ops.
+func init() {
+ debugFunc = Debug
+}
+
+var (
+ blanks = bytes.Repeat([]byte{' '}, 3*10)
+ empty = []byte(": <empty>\n")
+ tabs = strings.Repeat("\t", 100)
+)
+
+// tab indents itself when printed.
+type tab int
+
+func (t tab) String() string {
+ n := int(t)
+ if n > len(tabs) {
+ n = len(tabs)
+ }
+ return tabs[0:n]
+}
+
+func (t tab) print() {
+ fmt.Fprint(os.Stderr, t)
+}
+
+// A peekReader wraps an io.Reader, allowing one to peek ahead to see
+// what's coming without stealing the data from the client of the Reader.
+type peekReader struct {
+ r io.Reader
+ data []byte // read-ahead data
+}
+
+// newPeekReader returns a peekReader that wraps r.
+func newPeekReader(r io.Reader) *peekReader {
+ return &peekReader{r: r}
+}
+
+// Read is the usual method. It will first take data that has been read ahead.
+func (p *peekReader) Read(b []byte) (n int, err error) {
+ if len(p.data) == 0 {
+ return p.r.Read(b)
+ }
+ // Satisfy what's possible from the read-ahead data.
+ n = copy(b, p.data)
+ // Move data down to beginning of slice, to avoid endless growth
+ copy(p.data, p.data[n:])
+ p.data = p.data[:len(p.data)-n]
+ return
+}
+
+// peek returns as many bytes as possible from the unread
+// portion of the stream, up to the length of b.
+func (p *peekReader) peek(b []byte) (n int, err error) {
+ if len(p.data) > 0 {
+ n = copy(b, p.data)
+ if n == len(b) {
+ return
+ }
+ b = b[n:]
+ }
+ if len(b) == 0 {
+ return
+ }
+ m, e := io.ReadFull(p.r, b)
+ if m > 0 {
+ p.data = append(p.data, b[:m]...)
+ }
+ n += m
+ if e == io.ErrUnexpectedEOF {
+ // That means m > 0 but we reached EOF. If we got data
+ // we won't complain about not being able to peek enough.
+ if n > 0 {
+ e = nil
+ } else {
+ e = io.EOF
+ }
+ }
+ return n, e
+}
+
+type debugger struct {
+ mutex sync.Mutex
+ remain int // the number of bytes known to remain in the input
+ remainingKnown bool // the value of 'remain' is valid
+ r *peekReader
+ wireType map[typeId]*wireType
+ tmp []byte // scratch space for decoding uints.
+}
+
+// dump prints the next nBytes of the input.
+// It arranges to print the output aligned from call to
+// call, to make it easy to see what has been consumed.
+func (deb *debugger) dump(format string, args ...interface{}) {
+ if !dumpBytes {
+ return
+ }
+ fmt.Fprintf(os.Stderr, format+" ", args...)
+ if !deb.remainingKnown {
+ return
+ }
+ if deb.remain < 0 {
+ fmt.Fprintf(os.Stderr, "remaining byte count is negative! %d\n", deb.remain)
+ return
+ }
+ data := make([]byte, deb.remain)
+ n, _ := deb.r.peek(data)
+ if n == 0 {
+ os.Stderr.Write(empty)
+ return
+ }
+ b := new(bytes.Buffer)
+ fmt.Fprintf(b, "[%d]{\n", deb.remain)
+ // Blanks until first byte
+ lineLength := 0
+ if n := len(data); n%10 != 0 {
+ lineLength = 10 - n%10
+ fmt.Fprintf(b, "\t%s", blanks[:lineLength*3])
+ }
+ // 10 bytes per line
+ for len(data) > 0 {
+ if lineLength == 0 {
+ fmt.Fprint(b, "\t")
+ }
+ m := 10 - lineLength
+ lineLength = 0
+ if m > len(data) {
+ m = len(data)
+ }
+ fmt.Fprintf(b, "% x\n", data[:m])
+ data = data[m:]
+ }
+ fmt.Fprint(b, "}\n")
+ os.Stderr.Write(b.Bytes())
+}
+
+// Debug prints a human-readable representation of the gob data read from r.
+// It is a no-op unless debugging was enabled when the package was built.
+func Debug(r io.Reader) {
+ err := debug(r)
+ if err != nil {
+ fmt.Fprintf(os.Stderr, "gob debug: %s\n", err)
+ }
+}
+
+// debug implements Debug, but catches panics and returns
+// them as errors to be printed by Debug.
+func debug(r io.Reader) (err error) {
+ defer catchError(&err)
+ fmt.Fprintln(os.Stderr, "Start of debugging")
+ deb := &debugger{
+ r: newPeekReader(r),
+ wireType: make(map[typeId]*wireType),
+ tmp: make([]byte, 16),
+ }
+ if b, ok := r.(*bytes.Buffer); ok {
+ deb.remain = b.Len()
+ deb.remainingKnown = true
+ }
+ deb.gobStream()
+ return
+}
+
+// note that we've consumed some bytes
+func (deb *debugger) consumed(n int) {
+ if deb.remainingKnown {
+ deb.remain -= n
+ }
+}
+
+// int64 decodes and returns the next integer, which must be present.
+// Don't call this if you could be at EOF.
+func (deb *debugger) int64() int64 {
+ return toInt(deb.uint64())
+}
+
+// uint64 returns and decodes the next unsigned integer, which must be present.
+// Don't call this if you could be at EOF.
+// TODO: handle errors better.
+func (deb *debugger) uint64() uint64 {
+ n, w, err := decodeUintReader(deb.r, deb.tmp)
+ if err != nil {
+ errorf("debug: read error: %s", err)
+ }
+ deb.consumed(w)
+ return n
+}
+
+// GobStream:
+// DelimitedMessage* (until EOF)
+func (deb *debugger) gobStream() {
+ // Make sure we're single-threaded through here.
+ deb.mutex.Lock()
+ defer deb.mutex.Unlock()
+
+ for deb.delimitedMessage(0) {
+ }
+}
+
+// DelimitedMessage:
+// uint(lengthOfMessage) Message
+func (deb *debugger) delimitedMessage(indent tab) bool {
+ for {
+ n := deb.loadBlock(true)
+ if n < 0 {
+ return false
+ }
+ deb.dump("Delimited message of length %d", n)
+ deb.message(indent)
+ }
+ return true
+}
+
+// loadBlock preps us to read a message
+// of the length specified next in the input. It returns
+// the length of the block. The argument tells whether
+// an EOF is acceptable now. If it is and one is found,
+// the return value is negative.
+func (deb *debugger) loadBlock(eofOK bool) int {
+ n64, w, err := decodeUintReader(deb.r, deb.tmp) // deb.uint64 will error at EOF
+ if err != nil {
+ if eofOK && err == io.EOF {
+ return -1
+ }
+ errorf("debug: unexpected error: %s", err)
+ }
+ deb.consumed(w)
+ n := int(n64)
+ if n < 0 {
+ errorf("huge value for message length: %d", n64)
+ }
+ return int(n)
+}
+
+// Message:
+// TypeSequence TypedValue
+// TypeSequence
+// (TypeDefinition DelimitedTypeDefinition*)?
+// DelimitedTypeDefinition:
+// uint(lengthOfTypeDefinition) TypeDefinition
+// TypedValue:
+// int(typeId) Value
+func (deb *debugger) message(indent tab) bool {
+ for {
+ // Convert the uint64 to a signed integer typeId
+ uid := deb.int64()
+ id := typeId(uid)
+ deb.dump("type id=%d", id)
+ if id < 0 {
+ deb.typeDefinition(indent, -id)
+ n := deb.loadBlock(false)
+ deb.dump("Message of length %d", n)
+ continue
+ } else {
+ deb.value(indent, id)
+ break
+ }
+ }
+ return true
+}
+
+// Helper methods to make it easy to scan a type descriptor.
+
+// common returns the CommonType at the input point.
+func (deb *debugger) common() CommonType {
+ fieldNum := -1
+ name := ""
+ id := typeId(0)
+ for {
+ delta := deb.delta(-1)
+ if delta == 0 {
+ break
+ }
+ fieldNum += delta
+ switch fieldNum {
+ case 0:
+ name = deb.string()
+ case 1:
+ // Id typeId
+ id = deb.typeId()
+ default:
+ errorf("corrupted CommonType, delta is %d fieldNum is %d", delta, fieldNum)
+ }
+ }
+ return CommonType{name, id}
+}
+
+// uint returns the unsigned int at the input point, as a uint (not uint64).
+func (deb *debugger) uint() uint {
+ return uint(deb.uint64())
+}
+
+// int returns the signed int at the input point, as an int (not int64).
+func (deb *debugger) int() int {
+ return int(deb.int64())
+}
+
+// typeId returns the type id at the input point.
+func (deb *debugger) typeId() typeId {
+ return typeId(deb.int64())
+}
+
+// string returns the string at the input point.
+func (deb *debugger) string() string {
+ x := int(deb.uint64())
+ b := make([]byte, x)
+ nb, _ := deb.r.Read(b)
+ if nb != x {
+ errorf("corrupted type")
+ }
+ deb.consumed(nb)
+ return string(b)
+}
+
+// delta returns the field delta at the input point. The expect argument,
+// if non-negative, identifies what the value should be.
+func (deb *debugger) delta(expect int) int {
+ delta := int(deb.uint64())
+ if delta < 0 || (expect >= 0 && delta != expect) {
+ errorf("decode: corrupted type: delta %d expected %d", delta, expect)
+ }
+ return delta
+}
+
+// TypeDefinition:
+// [int(-typeId) (already read)] encodingOfWireType
+func (deb *debugger) typeDefinition(indent tab, id typeId) {
+ deb.dump("type definition for id %d", id)
+ // Encoding is of a wireType. Decode the structure as usual
+ fieldNum := -1
+ wire := new(wireType)
+ // A wireType defines a single field.
+ delta := deb.delta(-1)
+ fieldNum += delta
+ switch fieldNum {
+ case 0: // array type, one field of {{Common}, elem, length}
+ // Field number 0 is CommonType
+ deb.delta(1)
+ com := deb.common()
+ // Field number 1 is type Id of elem
+ deb.delta(1)
+ id := deb.typeId()
+ // Field number 3 is length
+ deb.delta(1)
+ length := deb.int()
+ wire.ArrayT = &arrayType{com, id, length}
+
+ case 1: // slice type, one field of {{Common}, elem}
+ // Field number 0 is CommonType
+ deb.delta(1)
+ com := deb.common()
+ // Field number 1 is type Id of elem
+ deb.delta(1)
+ id := deb.typeId()
+ wire.SliceT = &sliceType{com, id}
+
+ case 2: // struct type, one field of {{Common}, []fieldType}
+ // Field number 0 is CommonType
+ deb.delta(1)
+ com := deb.common()
+ // Field number 1 is slice of FieldType
+ deb.delta(1)
+ numField := int(deb.uint())
+ field := make([]*fieldType, numField)
+ for i := 0; i < numField; i++ {
+ field[i] = new(fieldType)
+ deb.delta(1) // field 0 of fieldType: name
+ field[i].Name = deb.string()
+ deb.delta(1) // field 1 of fieldType: id
+ field[i].Id = deb.typeId()
+ deb.delta(0) // end of fieldType
+ }
+ wire.StructT = &structType{com, field}
+
+ case 3: // map type, one field of {{Common}, key, elem}
+ // Field number 0 is CommonType
+ deb.delta(1)
+ com := deb.common()
+ // Field number 1 is type Id of key
+ deb.delta(1)
+ keyId := deb.typeId()
+ // Field number 2 is type Id of elem
+ deb.delta(1)
+ elemId := deb.typeId()
+ wire.MapT = &mapType{com, keyId, elemId}
+ case 4: // GobEncoder type, one field of {{Common}}
+ // Field number 0 is CommonType
+ deb.delta(1)
+ com := deb.common()
+ wire.GobEncoderT = &gobEncoderType{com}
+ case 5: // BinaryMarshaler type, one field of {{Common}}
+ // Field number 0 is CommonType
+ deb.delta(1)
+ com := deb.common()
+ wire.BinaryMarshalerT = &gobEncoderType{com}
+ case 6: // TextMarshaler type, one field of {{Common}}
+ // Field number 0 is CommonType
+ deb.delta(1)
+ com := deb.common()
+ wire.TextMarshalerT = &gobEncoderType{com}
+ default:
+ errorf("bad field in type %d", fieldNum)
+ }
+ deb.printWireType(indent, wire)
+ deb.delta(0) // end inner type (arrayType, etc.)
+ deb.delta(0) // end wireType
+ // Remember we've seen this type.
+ deb.wireType[id] = wire
+}
+
+// Value:
+// SingletonValue | StructValue
+func (deb *debugger) value(indent tab, id typeId) {
+ wire, ok := deb.wireType[id]
+ if ok && wire.StructT != nil {
+ deb.structValue(indent, id)
+ } else {
+ deb.singletonValue(indent, id)
+ }
+}
+
+// SingletonValue:
+// uint(0) FieldValue
+func (deb *debugger) singletonValue(indent tab, id typeId) {
+ deb.dump("Singleton value")
+ // is it a builtin type?
+ wire := deb.wireType[id]
+ _, ok := builtinIdToType[id]
+ if !ok && wire == nil {
+ errorf("type id %d not defined", id)
+ }
+ m := deb.uint64()
+ if m != 0 {
+ errorf("expected zero; got %d", m)
+ }
+ deb.fieldValue(indent, id)
+}
+
+// InterfaceValue:
+// NilInterfaceValue | NonNilInterfaceValue
+func (deb *debugger) interfaceValue(indent tab) {
+ deb.dump("Start of interface value")
+ if nameLen := deb.uint64(); nameLen == 0 {
+ deb.nilInterfaceValue(indent)
+ } else {
+ deb.nonNilInterfaceValue(indent, int(nameLen))
+ }
+}
+
+// NilInterfaceValue:
+// uint(0) [already read]
+func (deb *debugger) nilInterfaceValue(indent tab) int {
+ fmt.Fprintf(os.Stderr, "%snil interface\n", indent)
+ return 0
+}
+
+// NonNilInterfaceValue:
+// ConcreteTypeName TypeSequence InterfaceContents
+// ConcreteTypeName:
+// uint(lengthOfName) [already read=n] name
+// InterfaceContents:
+// int(concreteTypeId) DelimitedValue
+// DelimitedValue:
+// uint(length) Value
+func (deb *debugger) nonNilInterfaceValue(indent tab, nameLen int) {
+ // ConcreteTypeName
+ b := make([]byte, nameLen)
+ deb.r.Read(b) // TODO: CHECK THESE READS!!
+ deb.consumed(nameLen)
+ name := string(b)
+
+ for {
+ id := deb.typeId()
+ if id < 0 {
+ deb.typeDefinition(indent, -id)
+ n := deb.loadBlock(false)
+ deb.dump("Nested message of length %d", n)
+ } else {
+ // DelimitedValue
+ x := deb.uint64() // in case we want to ignore the value; we don't.
+ fmt.Fprintf(os.Stderr, "%sinterface value, type %q id=%d; valueLength %d\n", indent, name, id, x)
+ deb.value(indent, id)
+ break
+ }
+ }
+}
+
+// printCommonType prints a common type; used by printWireType.
+func (deb *debugger) printCommonType(indent tab, kind string, common *CommonType) {
+ indent.print()
+ fmt.Fprintf(os.Stderr, "%s %q id=%d\n", kind, common.Name, common.Id)
+}
+
+// printWireType prints the contents of a wireType.
+func (deb *debugger) printWireType(indent tab, wire *wireType) {
+ fmt.Fprintf(os.Stderr, "%stype definition {\n", indent)
+ indent++
+ switch {
+ case wire.ArrayT != nil:
+ deb.printCommonType(indent, "array", &wire.ArrayT.CommonType)
+ fmt.Fprintf(os.Stderr, "%slen %d\n", indent+1, wire.ArrayT.Len)
+ fmt.Fprintf(os.Stderr, "%selemid %d\n", indent+1, wire.ArrayT.Elem)
+ case wire.MapT != nil:
+ deb.printCommonType(indent, "map", &wire.MapT.CommonType)
+ fmt.Fprintf(os.Stderr, "%skey id=%d\n", indent+1, wire.MapT.Key)
+ fmt.Fprintf(os.Stderr, "%selem id=%d\n", indent+1, wire.MapT.Elem)
+ case wire.SliceT != nil:
+ deb.printCommonType(indent, "slice", &wire.SliceT.CommonType)
+ fmt.Fprintf(os.Stderr, "%selem id=%d\n", indent+1, wire.SliceT.Elem)
+ case wire.StructT != nil:
+ deb.printCommonType(indent, "struct", &wire.StructT.CommonType)
+ for i, field := range wire.StructT.Field {
+ fmt.Fprintf(os.Stderr, "%sfield %d:\t%s\tid=%d\n", indent+1, i, field.Name, field.Id)
+ }
+ case wire.GobEncoderT != nil:
+ deb.printCommonType(indent, "GobEncoder", &wire.GobEncoderT.CommonType)
+ }
+ indent--
+ fmt.Fprintf(os.Stderr, "%s}\n", indent)
+}
+
+// fieldValue prints a value of any type, such as a struct field.
+// FieldValue:
+// builtinValue | ArrayValue | MapValue | SliceValue | StructValue | InterfaceValue
+func (deb *debugger) fieldValue(indent tab, id typeId) {
+ _, ok := builtinIdToType[id]
+ if ok {
+ if id == tInterface {
+ deb.interfaceValue(indent)
+ } else {
+ deb.printBuiltin(indent, id)
+ }
+ return
+ }
+ wire, ok := deb.wireType[id]
+ if !ok {
+ errorf("type id %d not defined", id)
+ }
+ switch {
+ case wire.ArrayT != nil:
+ deb.arrayValue(indent, wire)
+ case wire.MapT != nil:
+ deb.mapValue(indent, wire)
+ case wire.SliceT != nil:
+ deb.sliceValue(indent, wire)
+ case wire.StructT != nil:
+ deb.structValue(indent, id)
+ case wire.GobEncoderT != nil:
+ deb.gobEncoderValue(indent, id)
+ default:
+ panic("bad wire type for field")
+ }
+}
+
+// printBuiltin prints a value not of a fundamental type, that is,
+// one whose type is known to gobs at bootstrap time.
+func (deb *debugger) printBuiltin(indent tab, id typeId) {
+ switch id {
+ case tBool:
+ x := deb.int64()
+ if x == 0 {
+ fmt.Fprintf(os.Stderr, "%sfalse\n", indent)
+ } else {
+ fmt.Fprintf(os.Stderr, "%strue\n", indent)
+ }
+ case tInt:
+ x := deb.int64()
+ fmt.Fprintf(os.Stderr, "%s%d\n", indent, x)
+ case tUint:
+ x := deb.uint64()
+ fmt.Fprintf(os.Stderr, "%s%d\n", indent, x)
+ case tFloat:
+ x := deb.uint64()
+ fmt.Fprintf(os.Stderr, "%s%g\n", indent, float64FromBits(x))
+ case tComplex:
+ r := deb.uint64()
+ i := deb.uint64()
+ fmt.Fprintf(os.Stderr, "%s%g+%gi\n", indent, float64FromBits(r), float64FromBits(i))
+ case tBytes:
+ x := int(deb.uint64())
+ b := make([]byte, x)
+ deb.r.Read(b)
+ deb.consumed(x)
+ fmt.Fprintf(os.Stderr, "%s{% x}=%q\n", indent, b, b)
+ case tString:
+ x := int(deb.uint64())
+ b := make([]byte, x)
+ deb.r.Read(b)
+ deb.consumed(x)
+ fmt.Fprintf(os.Stderr, "%s%q\n", indent, b)
+ default:
+ panic("unknown builtin")
+ }
+}
+
+// ArrayValue:
+// uint(n) FieldValue*n
+func (deb *debugger) arrayValue(indent tab, wire *wireType) {
+ elemId := wire.ArrayT.Elem
+ u := deb.uint64()
+ length := int(u)
+ for i := 0; i < length; i++ {
+ deb.fieldValue(indent, elemId)
+ }
+ if length != wire.ArrayT.Len {
+ fmt.Fprintf(os.Stderr, "%s(wrong length for array: %d should be %d)\n", indent, length, wire.ArrayT.Len)
+ }
+}
+
+// MapValue:
+// uint(n) (FieldValue FieldValue)*n [n (key, value) pairs]
+func (deb *debugger) mapValue(indent tab, wire *wireType) {
+ keyId := wire.MapT.Key
+ elemId := wire.MapT.Elem
+ u := deb.uint64()
+ length := int(u)
+ for i := 0; i < length; i++ {
+ deb.fieldValue(indent+1, keyId)
+ deb.fieldValue(indent+1, elemId)
+ }
+}
+
+// SliceValue:
+// uint(n) (n FieldValue)
+func (deb *debugger) sliceValue(indent tab, wire *wireType) {
+ elemId := wire.SliceT.Elem
+ u := deb.uint64()
+ length := int(u)
+ deb.dump("Start of slice of length %d", length)
+
+ for i := 0; i < length; i++ {
+ deb.fieldValue(indent, elemId)
+ }
+}
+
+// StructValue:
+// (uint(fieldDelta) FieldValue)*
+func (deb *debugger) structValue(indent tab, id typeId) {
+ deb.dump("Start of struct value of %q id=%d\n<<\n", id.name(), id)
+ fmt.Fprintf(os.Stderr, "%s%s struct {\n", indent, id.name())
+ wire, ok := deb.wireType[id]
+ if !ok {
+ errorf("type id %d not defined", id)
+ }
+ strct := wire.StructT
+ fieldNum := -1
+ indent++
+ for {
+ delta := deb.uint64()
+ if delta == 0 { // struct terminator is zero delta fieldnum
+ break
+ }
+ fieldNum += int(delta)
+ if fieldNum < 0 || fieldNum >= len(strct.Field) {
+ deb.dump("field number out of range: prevField=%d delta=%d", fieldNum-int(delta), delta)
+ break
+ }
+ fmt.Fprintf(os.Stderr, "%sfield %d:\t%s\n", indent, fieldNum, wire.StructT.Field[fieldNum].Name)
+ deb.fieldValue(indent+1, strct.Field[fieldNum].Id)
+ }
+ indent--
+ fmt.Fprintf(os.Stderr, "%s} // end %s struct\n", indent, id.name())
+ deb.dump(">> End of struct value of type %d %q", id, id.name())
+}
+
+// GobEncoderValue:
+// uint(n) byte*n
+func (deb *debugger) gobEncoderValue(indent tab, id typeId) {
+ len := deb.uint64()
+ deb.dump("GobEncoder value of %q id=%d, length %d\n", id.name(), id, len)
+ fmt.Fprintf(os.Stderr, "%s%s (implements GobEncoder)\n", indent, id.name())
+ data := make([]byte, len)
+ _, err := deb.r.Read(data)
+ if err != nil {
+ errorf("gobEncoder data read: %s", err)
+ }
+ fmt.Fprintf(os.Stderr, "%s[% .2x]\n", indent+1, data)
+}
diff --git a/src/encoding/gob/dec_helpers.go b/src/encoding/gob/dec_helpers.go
new file mode 100644
index 0000000..26eb9e4
--- /dev/null
+++ b/src/encoding/gob/dec_helpers.go
@@ -0,0 +1,469 @@
+// Code generated by go run decgen.go -output dec_helpers.go; DO NOT EDIT.
+
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gob
+
+import (
+ "math"
+ "reflect"
+)
+
+var decArrayHelper = map[reflect.Kind]decHelper{
+ reflect.Bool: decBoolArray,
+ reflect.Complex64: decComplex64Array,
+ reflect.Complex128: decComplex128Array,
+ reflect.Float32: decFloat32Array,
+ reflect.Float64: decFloat64Array,
+ reflect.Int: decIntArray,
+ reflect.Int16: decInt16Array,
+ reflect.Int32: decInt32Array,
+ reflect.Int64: decInt64Array,
+ reflect.Int8: decInt8Array,
+ reflect.String: decStringArray,
+ reflect.Uint: decUintArray,
+ reflect.Uint16: decUint16Array,
+ reflect.Uint32: decUint32Array,
+ reflect.Uint64: decUint64Array,
+ reflect.Uintptr: decUintptrArray,
+}
+
+var decSliceHelper = map[reflect.Kind]decHelper{
+ reflect.Bool: decBoolSlice,
+ reflect.Complex64: decComplex64Slice,
+ reflect.Complex128: decComplex128Slice,
+ reflect.Float32: decFloat32Slice,
+ reflect.Float64: decFloat64Slice,
+ reflect.Int: decIntSlice,
+ reflect.Int16: decInt16Slice,
+ reflect.Int32: decInt32Slice,
+ reflect.Int64: decInt64Slice,
+ reflect.Int8: decInt8Slice,
+ reflect.String: decStringSlice,
+ reflect.Uint: decUintSlice,
+ reflect.Uint16: decUint16Slice,
+ reflect.Uint32: decUint32Slice,
+ reflect.Uint64: decUint64Slice,
+ reflect.Uintptr: decUintptrSlice,
+}
+
+func decBoolArray(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return decBoolSlice(state, v.Slice(0, v.Len()), length, ovfl)
+}
+
+func decBoolSlice(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ slice, ok := v.Interface().([]bool)
+ if !ok {
+ // It is kind bool but not type bool. TODO: We can handle this unsafely.
+ return false
+ }
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding bool array or slice: length exceeds input size (%d elements)", length)
+ }
+ slice[i] = state.decodeUint() != 0
+ }
+ return true
+}
+
+func decComplex64Array(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return decComplex64Slice(state, v.Slice(0, v.Len()), length, ovfl)
+}
+
+func decComplex64Slice(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ slice, ok := v.Interface().([]complex64)
+ if !ok {
+ // It is kind complex64 but not type complex64. TODO: We can handle this unsafely.
+ return false
+ }
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding complex64 array or slice: length exceeds input size (%d elements)", length)
+ }
+ real := float32FromBits(state.decodeUint(), ovfl)
+ imag := float32FromBits(state.decodeUint(), ovfl)
+ slice[i] = complex(float32(real), float32(imag))
+ }
+ return true
+}
+
+func decComplex128Array(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return decComplex128Slice(state, v.Slice(0, v.Len()), length, ovfl)
+}
+
+func decComplex128Slice(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ slice, ok := v.Interface().([]complex128)
+ if !ok {
+ // It is kind complex128 but not type complex128. TODO: We can handle this unsafely.
+ return false
+ }
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding complex128 array or slice: length exceeds input size (%d elements)", length)
+ }
+ real := float64FromBits(state.decodeUint())
+ imag := float64FromBits(state.decodeUint())
+ slice[i] = complex(real, imag)
+ }
+ return true
+}
+
+func decFloat32Array(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return decFloat32Slice(state, v.Slice(0, v.Len()), length, ovfl)
+}
+
+func decFloat32Slice(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ slice, ok := v.Interface().([]float32)
+ if !ok {
+ // It is kind float32 but not type float32. TODO: We can handle this unsafely.
+ return false
+ }
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding float32 array or slice: length exceeds input size (%d elements)", length)
+ }
+ slice[i] = float32(float32FromBits(state.decodeUint(), ovfl))
+ }
+ return true
+}
+
+func decFloat64Array(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return decFloat64Slice(state, v.Slice(0, v.Len()), length, ovfl)
+}
+
+func decFloat64Slice(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ slice, ok := v.Interface().([]float64)
+ if !ok {
+ // It is kind float64 but not type float64. TODO: We can handle this unsafely.
+ return false
+ }
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding float64 array or slice: length exceeds input size (%d elements)", length)
+ }
+ slice[i] = float64FromBits(state.decodeUint())
+ }
+ return true
+}
+
+func decIntArray(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return decIntSlice(state, v.Slice(0, v.Len()), length, ovfl)
+}
+
+func decIntSlice(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ slice, ok := v.Interface().([]int)
+ if !ok {
+ // It is kind int but not type int. TODO: We can handle this unsafely.
+ return false
+ }
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding int array or slice: length exceeds input size (%d elements)", length)
+ }
+ x := state.decodeInt()
+ // MinInt and MaxInt
+ if x < ^int64(^uint(0)>>1) || int64(^uint(0)>>1) < x {
+ error_(ovfl)
+ }
+ slice[i] = int(x)
+ }
+ return true
+}
+
+func decInt16Array(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return decInt16Slice(state, v.Slice(0, v.Len()), length, ovfl)
+}
+
+func decInt16Slice(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ slice, ok := v.Interface().([]int16)
+ if !ok {
+ // It is kind int16 but not type int16. TODO: We can handle this unsafely.
+ return false
+ }
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding int16 array or slice: length exceeds input size (%d elements)", length)
+ }
+ x := state.decodeInt()
+ if x < math.MinInt16 || math.MaxInt16 < x {
+ error_(ovfl)
+ }
+ slice[i] = int16(x)
+ }
+ return true
+}
+
+func decInt32Array(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return decInt32Slice(state, v.Slice(0, v.Len()), length, ovfl)
+}
+
+func decInt32Slice(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ slice, ok := v.Interface().([]int32)
+ if !ok {
+ // It is kind int32 but not type int32. TODO: We can handle this unsafely.
+ return false
+ }
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding int32 array or slice: length exceeds input size (%d elements)", length)
+ }
+ x := state.decodeInt()
+ if x < math.MinInt32 || math.MaxInt32 < x {
+ error_(ovfl)
+ }
+ slice[i] = int32(x)
+ }
+ return true
+}
+
+func decInt64Array(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return decInt64Slice(state, v.Slice(0, v.Len()), length, ovfl)
+}
+
+func decInt64Slice(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ slice, ok := v.Interface().([]int64)
+ if !ok {
+ // It is kind int64 but not type int64. TODO: We can handle this unsafely.
+ return false
+ }
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding int64 array or slice: length exceeds input size (%d elements)", length)
+ }
+ slice[i] = state.decodeInt()
+ }
+ return true
+}
+
+func decInt8Array(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return decInt8Slice(state, v.Slice(0, v.Len()), length, ovfl)
+}
+
+func decInt8Slice(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ slice, ok := v.Interface().([]int8)
+ if !ok {
+ // It is kind int8 but not type int8. TODO: We can handle this unsafely.
+ return false
+ }
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding int8 array or slice: length exceeds input size (%d elements)", length)
+ }
+ x := state.decodeInt()
+ if x < math.MinInt8 || math.MaxInt8 < x {
+ error_(ovfl)
+ }
+ slice[i] = int8(x)
+ }
+ return true
+}
+
+func decStringArray(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return decStringSlice(state, v.Slice(0, v.Len()), length, ovfl)
+}
+
+func decStringSlice(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ slice, ok := v.Interface().([]string)
+ if !ok {
+ // It is kind string but not type string. TODO: We can handle this unsafely.
+ return false
+ }
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding string array or slice: length exceeds input size (%d elements)", length)
+ }
+ u := state.decodeUint()
+ n := int(u)
+ if n < 0 || uint64(n) != u || n > state.b.Len() {
+ errorf("length of string exceeds input size (%d bytes)", u)
+ }
+ if n > state.b.Len() {
+ errorf("string data too long for buffer: %d", n)
+ }
+ // Read the data.
+ data := state.b.Bytes()
+ if len(data) < n {
+ errorf("invalid string length %d: exceeds input size %d", n, len(data))
+ }
+ slice[i] = string(data[:n])
+ state.b.Drop(n)
+ }
+ return true
+}
+
+func decUintArray(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return decUintSlice(state, v.Slice(0, v.Len()), length, ovfl)
+}
+
+func decUintSlice(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ slice, ok := v.Interface().([]uint)
+ if !ok {
+ // It is kind uint but not type uint. TODO: We can handle this unsafely.
+ return false
+ }
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding uint array or slice: length exceeds input size (%d elements)", length)
+ }
+ x := state.decodeUint()
+ /*TODO if math.MaxUint32 < x {
+ error_(ovfl)
+ }*/
+ slice[i] = uint(x)
+ }
+ return true
+}
+
+func decUint16Array(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return decUint16Slice(state, v.Slice(0, v.Len()), length, ovfl)
+}
+
+func decUint16Slice(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ slice, ok := v.Interface().([]uint16)
+ if !ok {
+ // It is kind uint16 but not type uint16. TODO: We can handle this unsafely.
+ return false
+ }
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding uint16 array or slice: length exceeds input size (%d elements)", length)
+ }
+ x := state.decodeUint()
+ if math.MaxUint16 < x {
+ error_(ovfl)
+ }
+ slice[i] = uint16(x)
+ }
+ return true
+}
+
+func decUint32Array(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return decUint32Slice(state, v.Slice(0, v.Len()), length, ovfl)
+}
+
+func decUint32Slice(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ slice, ok := v.Interface().([]uint32)
+ if !ok {
+ // It is kind uint32 but not type uint32. TODO: We can handle this unsafely.
+ return false
+ }
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding uint32 array or slice: length exceeds input size (%d elements)", length)
+ }
+ x := state.decodeUint()
+ if math.MaxUint32 < x {
+ error_(ovfl)
+ }
+ slice[i] = uint32(x)
+ }
+ return true
+}
+
+func decUint64Array(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return decUint64Slice(state, v.Slice(0, v.Len()), length, ovfl)
+}
+
+func decUint64Slice(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ slice, ok := v.Interface().([]uint64)
+ if !ok {
+ // It is kind uint64 but not type uint64. TODO: We can handle this unsafely.
+ return false
+ }
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding uint64 array or slice: length exceeds input size (%d elements)", length)
+ }
+ slice[i] = state.decodeUint()
+ }
+ return true
+}
+
+func decUintptrArray(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return decUintptrSlice(state, v.Slice(0, v.Len()), length, ovfl)
+}
+
+func decUintptrSlice(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ slice, ok := v.Interface().([]uintptr)
+ if !ok {
+ // It is kind uintptr but not type uintptr. TODO: We can handle this unsafely.
+ return false
+ }
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding uintptr array or slice: length exceeds input size (%d elements)", length)
+ }
+ x := state.decodeUint()
+ if uint64(^uintptr(0)) < x {
+ error_(ovfl)
+ }
+ slice[i] = uintptr(x)
+ }
+ return true
+}
diff --git a/src/encoding/gob/decgen.go b/src/encoding/gob/decgen.go
new file mode 100644
index 0000000..994be87
--- /dev/null
+++ b/src/encoding/gob/decgen.go
@@ -0,0 +1,244 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build ignore
+// +build ignore
+
+// encgen writes the helper functions for encoding. Intended to be
+// used with go generate; see the invocation in encode.go.
+
+// TODO: We could do more by being unsafe. Add a -unsafe flag?
+
+package main
+
+import (
+ "bytes"
+ "flag"
+ "fmt"
+ "go/format"
+ "log"
+ "os"
+)
+
+var output = flag.String("output", "dec_helpers.go", "file name to write")
+
+type Type struct {
+ lower string
+ upper string
+ decoder string
+}
+
+var types = []Type{
+ {
+ "bool",
+ "Bool",
+ `slice[i] = state.decodeUint() != 0`,
+ },
+ {
+ "complex64",
+ "Complex64",
+ `real := float32FromBits(state.decodeUint(), ovfl)
+ imag := float32FromBits(state.decodeUint(), ovfl)
+ slice[i] = complex(float32(real), float32(imag))`,
+ },
+ {
+ "complex128",
+ "Complex128",
+ `real := float64FromBits(state.decodeUint())
+ imag := float64FromBits(state.decodeUint())
+ slice[i] = complex(real, imag)`,
+ },
+ {
+ "float32",
+ "Float32",
+ `slice[i] = float32(float32FromBits(state.decodeUint(), ovfl))`,
+ },
+ {
+ "float64",
+ "Float64",
+ `slice[i] = float64FromBits(state.decodeUint())`,
+ },
+ {
+ "int",
+ "Int",
+ `x := state.decodeInt()
+ // MinInt and MaxInt
+ if x < ^int64(^uint(0)>>1) || int64(^uint(0)>>1) < x {
+ error_(ovfl)
+ }
+ slice[i] = int(x)`,
+ },
+ {
+ "int16",
+ "Int16",
+ `x := state.decodeInt()
+ if x < math.MinInt16 || math.MaxInt16 < x {
+ error_(ovfl)
+ }
+ slice[i] = int16(x)`,
+ },
+ {
+ "int32",
+ "Int32",
+ `x := state.decodeInt()
+ if x < math.MinInt32 || math.MaxInt32 < x {
+ error_(ovfl)
+ }
+ slice[i] = int32(x)`,
+ },
+ {
+ "int64",
+ "Int64",
+ `slice[i] = state.decodeInt()`,
+ },
+ {
+ "int8",
+ "Int8",
+ `x := state.decodeInt()
+ if x < math.MinInt8 || math.MaxInt8 < x {
+ error_(ovfl)
+ }
+ slice[i] = int8(x)`,
+ },
+ {
+ "string",
+ "String",
+ `u := state.decodeUint()
+ n := int(u)
+ if n < 0 || uint64(n) != u || n > state.b.Len() {
+ errorf("length of string exceeds input size (%d bytes)", u)
+ }
+ if n > state.b.Len() {
+ errorf("string data too long for buffer: %d", n)
+ }
+ // Read the data.
+ data := state.b.Bytes()
+ if len(data) < n {
+ errorf("invalid string length %d: exceeds input size %d", n, len(data))
+ }
+ slice[i] = string(data[:n])
+ state.b.Drop(n)`,
+ },
+ {
+ "uint",
+ "Uint",
+ `x := state.decodeUint()
+ /*TODO if math.MaxUint32 < x {
+ error_(ovfl)
+ }*/
+ slice[i] = uint(x)`,
+ },
+ {
+ "uint16",
+ "Uint16",
+ `x := state.decodeUint()
+ if math.MaxUint16 < x {
+ error_(ovfl)
+ }
+ slice[i] = uint16(x)`,
+ },
+ {
+ "uint32",
+ "Uint32",
+ `x := state.decodeUint()
+ if math.MaxUint32 < x {
+ error_(ovfl)
+ }
+ slice[i] = uint32(x)`,
+ },
+ {
+ "uint64",
+ "Uint64",
+ `slice[i] = state.decodeUint()`,
+ },
+ {
+ "uintptr",
+ "Uintptr",
+ `x := state.decodeUint()
+ if uint64(^uintptr(0)) < x {
+ error_(ovfl)
+ }
+ slice[i] = uintptr(x)`,
+ },
+ // uint8 Handled separately.
+}
+
+func main() {
+ log.SetFlags(0)
+ log.SetPrefix("decgen: ")
+ flag.Parse()
+ if flag.NArg() != 0 {
+ log.Fatal("usage: decgen [--output filename]")
+ }
+ var b bytes.Buffer
+ fmt.Fprintf(&b, "// Code generated by go run decgen.go -output %s; DO NOT EDIT.\n", *output)
+ fmt.Fprint(&b, header)
+ printMaps(&b, "Array")
+ fmt.Fprint(&b, "\n")
+ printMaps(&b, "Slice")
+ for _, t := range types {
+ fmt.Fprintf(&b, arrayHelper, t.lower, t.upper)
+ fmt.Fprintf(&b, sliceHelper, t.lower, t.upper, t.decoder)
+ }
+ source, err := format.Source(b.Bytes())
+ if err != nil {
+ log.Fatal("source format error:", err)
+ }
+ fd, err := os.Create(*output)
+ if err != nil {
+ log.Fatal(err)
+ }
+ if _, err := fd.Write(source); err != nil {
+ log.Fatal(err)
+ }
+}
+
+func printMaps(b *bytes.Buffer, upperClass string) {
+ fmt.Fprintf(b, "var dec%sHelper = map[reflect.Kind]decHelper{\n", upperClass)
+ for _, t := range types {
+ fmt.Fprintf(b, "reflect.%s: dec%s%s,\n", t.upper, t.upper, upperClass)
+ }
+ fmt.Fprintf(b, "}\n")
+}
+
+const header = `
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gob
+
+import (
+ "math"
+ "reflect"
+)
+
+`
+
+const arrayHelper = `
+func dec%[2]sArray(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return dec%[2]sSlice(state, v.Slice(0, v.Len()), length, ovfl)
+}
+`
+
+const sliceHelper = `
+func dec%[2]sSlice(state *decoderState, v reflect.Value, length int, ovfl error) bool {
+ slice, ok := v.Interface().([]%[1]s)
+ if !ok {
+ // It is kind %[1]s but not type %[1]s. TODO: We can handle this unsafely.
+ return false
+ }
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding %[1]s array or slice: length exceeds input size (%%d elements)", length)
+ }
+ %[3]s
+ }
+ return true
+}
+`
diff --git a/src/encoding/gob/decode.go b/src/encoding/gob/decode.go
new file mode 100644
index 0000000..0e0ec75
--- /dev/null
+++ b/src/encoding/gob/decode.go
@@ -0,0 +1,1264 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:generate go run decgen.go -output dec_helpers.go
+
+package gob
+
+import (
+ "encoding"
+ "errors"
+ "io"
+ "math"
+ "math/bits"
+ "reflect"
+)
+
+var (
+ errBadUint = errors.New("gob: encoded unsigned integer out of range")
+ errBadType = errors.New("gob: unknown type id or corrupted data")
+ errRange = errors.New("gob: bad data: field numbers out of bounds")
+)
+
+type decHelper func(state *decoderState, v reflect.Value, length int, ovfl error) bool
+
+// decoderState is the execution state of an instance of the decoder. A new state
+// is created for nested objects.
+type decoderState struct {
+ dec *Decoder
+ // The buffer is stored with an extra indirection because it may be replaced
+ // if we load a type during decode (when reading an interface value).
+ b *decBuffer
+ fieldnum int // the last field number read.
+ next *decoderState // for free list
+}
+
+// decBuffer is an extremely simple, fast implementation of a read-only byte buffer.
+// It is initialized by calling Size and then copying the data into the slice returned by Bytes().
+type decBuffer struct {
+ data []byte
+ offset int // Read offset.
+}
+
+func (d *decBuffer) Read(p []byte) (int, error) {
+ n := copy(p, d.data[d.offset:])
+ if n == 0 && len(p) != 0 {
+ return 0, io.EOF
+ }
+ d.offset += n
+ return n, nil
+}
+
+func (d *decBuffer) Drop(n int) {
+ if n > d.Len() {
+ panic("drop")
+ }
+ d.offset += n
+}
+
+// Size grows the buffer to exactly n bytes, so d.Bytes() will
+// return a slice of length n. Existing data is first discarded.
+func (d *decBuffer) Size(n int) {
+ d.Reset()
+ if cap(d.data) < n {
+ d.data = make([]byte, n)
+ } else {
+ d.data = d.data[0:n]
+ }
+}
+
+func (d *decBuffer) ReadByte() (byte, error) {
+ if d.offset >= len(d.data) {
+ return 0, io.EOF
+ }
+ c := d.data[d.offset]
+ d.offset++
+ return c, nil
+}
+
+func (d *decBuffer) Len() int {
+ return len(d.data) - d.offset
+}
+
+func (d *decBuffer) Bytes() []byte {
+ return d.data[d.offset:]
+}
+
+func (d *decBuffer) Reset() {
+ d.data = d.data[0:0]
+ d.offset = 0
+}
+
+// We pass the bytes.Buffer separately for easier testing of the infrastructure
+// without requiring a full Decoder.
+func (dec *Decoder) newDecoderState(buf *decBuffer) *decoderState {
+ d := dec.freeList
+ if d == nil {
+ d = new(decoderState)
+ d.dec = dec
+ } else {
+ dec.freeList = d.next
+ }
+ d.b = buf
+ return d
+}
+
+func (dec *Decoder) freeDecoderState(d *decoderState) {
+ d.next = dec.freeList
+ dec.freeList = d
+}
+
+func overflow(name string) error {
+ return errors.New(`value for "` + name + `" out of range`)
+}
+
+// decodeUintReader reads an encoded unsigned integer from an io.Reader.
+// Used only by the Decoder to read the message length.
+func decodeUintReader(r io.Reader, buf []byte) (x uint64, width int, err error) {
+ width = 1
+ n, err := io.ReadFull(r, buf[0:width])
+ if n == 0 {
+ return
+ }
+ b := buf[0]
+ if b <= 0x7f {
+ return uint64(b), width, nil
+ }
+ n = -int(int8(b))
+ if n > uint64Size {
+ err = errBadUint
+ return
+ }
+ width, err = io.ReadFull(r, buf[0:n])
+ if err != nil {
+ if err == io.EOF {
+ err = io.ErrUnexpectedEOF
+ }
+ return
+ }
+ // Could check that the high byte is zero but it's not worth it.
+ for _, b := range buf[0:width] {
+ x = x<<8 | uint64(b)
+ }
+ width++ // +1 for length byte
+ return
+}
+
+// decodeUint reads an encoded unsigned integer from state.r.
+// Does not check for overflow.
+func (state *decoderState) decodeUint() (x uint64) {
+ b, err := state.b.ReadByte()
+ if err != nil {
+ error_(err)
+ }
+ if b <= 0x7f {
+ return uint64(b)
+ }
+ n := -int(int8(b))
+ if n > uint64Size {
+ error_(errBadUint)
+ }
+ buf := state.b.Bytes()
+ if len(buf) < n {
+ errorf("invalid uint data length %d: exceeds input size %d", n, len(buf))
+ }
+ // Don't need to check error; it's safe to loop regardless.
+ // Could check that the high byte is zero but it's not worth it.
+ for _, b := range buf[0:n] {
+ x = x<<8 | uint64(b)
+ }
+ state.b.Drop(n)
+ return x
+}
+
+// decodeInt reads an encoded signed integer from state.r.
+// Does not check for overflow.
+func (state *decoderState) decodeInt() int64 {
+ x := state.decodeUint()
+ if x&1 != 0 {
+ return ^int64(x >> 1)
+ }
+ return int64(x >> 1)
+}
+
+// getLength decodes the next uint and makes sure it is a possible
+// size for a data item that follows, which means it must fit in a
+// non-negative int and fit in the buffer.
+func (state *decoderState) getLength() (int, bool) {
+ n := int(state.decodeUint())
+ if n < 0 || state.b.Len() < n || tooBig <= n {
+ return 0, false
+ }
+ return n, true
+}
+
+// decOp is the signature of a decoding operator for a given type.
+type decOp func(i *decInstr, state *decoderState, v reflect.Value)
+
+// The 'instructions' of the decoding machine
+type decInstr struct {
+ op decOp
+ field int // field number of the wire type
+ index []int // field access indices for destination type
+ ovfl error // error message for overflow/underflow (for arrays, of the elements)
+}
+
+// ignoreUint discards a uint value with no destination.
+func ignoreUint(i *decInstr, state *decoderState, v reflect.Value) {
+ state.decodeUint()
+}
+
+// ignoreTwoUints discards a uint value with no destination. It's used to skip
+// complex values.
+func ignoreTwoUints(i *decInstr, state *decoderState, v reflect.Value) {
+ state.decodeUint()
+ state.decodeUint()
+}
+
+// Since the encoder writes no zeros, if we arrive at a decoder we have
+// a value to extract and store. The field number has already been read
+// (it's how we knew to call this decoder).
+// Each decoder is responsible for handling any indirections associated
+// with the data structure. If any pointer so reached is nil, allocation must
+// be done.
+
+// decAlloc takes a value and returns a settable value that can
+// be assigned to. If the value is a pointer, decAlloc guarantees it points to storage.
+// The callers to the individual decoders are expected to have used decAlloc.
+// The individual decoders don't need to it.
+func decAlloc(v reflect.Value) reflect.Value {
+ for v.Kind() == reflect.Ptr {
+ if v.IsNil() {
+ v.Set(reflect.New(v.Type().Elem()))
+ }
+ v = v.Elem()
+ }
+ return v
+}
+
+// decBool decodes a uint and stores it as a boolean in value.
+func decBool(i *decInstr, state *decoderState, value reflect.Value) {
+ value.SetBool(state.decodeUint() != 0)
+}
+
+// decInt8 decodes an integer and stores it as an int8 in value.
+func decInt8(i *decInstr, state *decoderState, value reflect.Value) {
+ v := state.decodeInt()
+ if v < math.MinInt8 || math.MaxInt8 < v {
+ error_(i.ovfl)
+ }
+ value.SetInt(v)
+}
+
+// decUint8 decodes an unsigned integer and stores it as a uint8 in value.
+func decUint8(i *decInstr, state *decoderState, value reflect.Value) {
+ v := state.decodeUint()
+ if math.MaxUint8 < v {
+ error_(i.ovfl)
+ }
+ value.SetUint(v)
+}
+
+// decInt16 decodes an integer and stores it as an int16 in value.
+func decInt16(i *decInstr, state *decoderState, value reflect.Value) {
+ v := state.decodeInt()
+ if v < math.MinInt16 || math.MaxInt16 < v {
+ error_(i.ovfl)
+ }
+ value.SetInt(v)
+}
+
+// decUint16 decodes an unsigned integer and stores it as a uint16 in value.
+func decUint16(i *decInstr, state *decoderState, value reflect.Value) {
+ v := state.decodeUint()
+ if math.MaxUint16 < v {
+ error_(i.ovfl)
+ }
+ value.SetUint(v)
+}
+
+// decInt32 decodes an integer and stores it as an int32 in value.
+func decInt32(i *decInstr, state *decoderState, value reflect.Value) {
+ v := state.decodeInt()
+ if v < math.MinInt32 || math.MaxInt32 < v {
+ error_(i.ovfl)
+ }
+ value.SetInt(v)
+}
+
+// decUint32 decodes an unsigned integer and stores it as a uint32 in value.
+func decUint32(i *decInstr, state *decoderState, value reflect.Value) {
+ v := state.decodeUint()
+ if math.MaxUint32 < v {
+ error_(i.ovfl)
+ }
+ value.SetUint(v)
+}
+
+// decInt64 decodes an integer and stores it as an int64 in value.
+func decInt64(i *decInstr, state *decoderState, value reflect.Value) {
+ v := state.decodeInt()
+ value.SetInt(v)
+}
+
+// decUint64 decodes an unsigned integer and stores it as a uint64 in value.
+func decUint64(i *decInstr, state *decoderState, value reflect.Value) {
+ v := state.decodeUint()
+ value.SetUint(v)
+}
+
+// Floating-point numbers are transmitted as uint64s holding the bits
+// of the underlying representation. They are sent byte-reversed, with
+// the exponent end coming out first, so integer floating point numbers
+// (for example) transmit more compactly. This routine does the
+// unswizzling.
+func float64FromBits(u uint64) float64 {
+ v := bits.ReverseBytes64(u)
+ return math.Float64frombits(v)
+}
+
+// float32FromBits decodes an unsigned integer, treats it as a 32-bit floating-point
+// number, and returns it. It's a helper function for float32 and complex64.
+// It returns a float64 because that's what reflection needs, but its return
+// value is known to be accurately representable in a float32.
+func float32FromBits(u uint64, ovfl error) float64 {
+ v := float64FromBits(u)
+ av := v
+ if av < 0 {
+ av = -av
+ }
+ // +Inf is OK in both 32- and 64-bit floats. Underflow is always OK.
+ if math.MaxFloat32 < av && av <= math.MaxFloat64 {
+ error_(ovfl)
+ }
+ return v
+}
+
+// decFloat32 decodes an unsigned integer, treats it as a 32-bit floating-point
+// number, and stores it in value.
+func decFloat32(i *decInstr, state *decoderState, value reflect.Value) {
+ value.SetFloat(float32FromBits(state.decodeUint(), i.ovfl))
+}
+
+// decFloat64 decodes an unsigned integer, treats it as a 64-bit floating-point
+// number, and stores it in value.
+func decFloat64(i *decInstr, state *decoderState, value reflect.Value) {
+ value.SetFloat(float64FromBits(state.decodeUint()))
+}
+
+// decComplex64 decodes a pair of unsigned integers, treats them as a
+// pair of floating point numbers, and stores them as a complex64 in value.
+// The real part comes first.
+func decComplex64(i *decInstr, state *decoderState, value reflect.Value) {
+ real := float32FromBits(state.decodeUint(), i.ovfl)
+ imag := float32FromBits(state.decodeUint(), i.ovfl)
+ value.SetComplex(complex(real, imag))
+}
+
+// decComplex128 decodes a pair of unsigned integers, treats them as a
+// pair of floating point numbers, and stores them as a complex128 in value.
+// The real part comes first.
+func decComplex128(i *decInstr, state *decoderState, value reflect.Value) {
+ real := float64FromBits(state.decodeUint())
+ imag := float64FromBits(state.decodeUint())
+ value.SetComplex(complex(real, imag))
+}
+
+// decUint8Slice decodes a byte slice and stores in value a slice header
+// describing the data.
+// uint8 slices are encoded as an unsigned count followed by the raw bytes.
+func decUint8Slice(i *decInstr, state *decoderState, value reflect.Value) {
+ n, ok := state.getLength()
+ if !ok {
+ errorf("bad %s slice length: %d", value.Type(), n)
+ }
+ if value.Cap() < n {
+ value.Set(reflect.MakeSlice(value.Type(), n, n))
+ } else {
+ value.Set(value.Slice(0, n))
+ }
+ if _, err := state.b.Read(value.Bytes()); err != nil {
+ errorf("error decoding []byte: %s", err)
+ }
+}
+
+// decString decodes byte array and stores in value a string header
+// describing the data.
+// Strings are encoded as an unsigned count followed by the raw bytes.
+func decString(i *decInstr, state *decoderState, value reflect.Value) {
+ n, ok := state.getLength()
+ if !ok {
+ errorf("bad %s slice length: %d", value.Type(), n)
+ }
+ // Read the data.
+ data := state.b.Bytes()
+ if len(data) < n {
+ errorf("invalid string length %d: exceeds input size %d", n, len(data))
+ }
+ s := string(data[:n])
+ state.b.Drop(n)
+ value.SetString(s)
+}
+
+// ignoreUint8Array skips over the data for a byte slice value with no destination.
+func ignoreUint8Array(i *decInstr, state *decoderState, value reflect.Value) {
+ n, ok := state.getLength()
+ if !ok {
+ errorf("slice length too large")
+ }
+ bn := state.b.Len()
+ if bn < n {
+ errorf("invalid slice length %d: exceeds input size %d", n, bn)
+ }
+ state.b.Drop(n)
+}
+
+// Execution engine
+
+// The encoder engine is an array of instructions indexed by field number of the incoming
+// decoder. It is executed with random access according to field number.
+type decEngine struct {
+ instr []decInstr
+ numInstr int // the number of active instructions
+}
+
+// decodeSingle decodes a top-level value that is not a struct and stores it in value.
+// Such values are preceded by a zero, making them have the memory layout of a
+// struct field (although with an illegal field number).
+func (dec *Decoder) decodeSingle(engine *decEngine, value reflect.Value) {
+ state := dec.newDecoderState(&dec.buf)
+ defer dec.freeDecoderState(state)
+ state.fieldnum = singletonField
+ if state.decodeUint() != 0 {
+ errorf("decode: corrupted data: non-zero delta for singleton")
+ }
+ instr := &engine.instr[singletonField]
+ instr.op(instr, state, value)
+}
+
+// decodeStruct decodes a top-level struct and stores it in value.
+// Indir is for the value, not the type. At the time of the call it may
+// differ from ut.indir, which was computed when the engine was built.
+// This state cannot arise for decodeSingle, which is called directly
+// from the user's value, not from the innards of an engine.
+func (dec *Decoder) decodeStruct(engine *decEngine, value reflect.Value) {
+ state := dec.newDecoderState(&dec.buf)
+ defer dec.freeDecoderState(state)
+ state.fieldnum = -1
+ for state.b.Len() > 0 {
+ delta := int(state.decodeUint())
+ if delta < 0 {
+ errorf("decode: corrupted data: negative delta")
+ }
+ if delta == 0 { // struct terminator is zero delta fieldnum
+ break
+ }
+ fieldnum := state.fieldnum + delta
+ if fieldnum >= len(engine.instr) {
+ error_(errRange)
+ break
+ }
+ instr := &engine.instr[fieldnum]
+ var field reflect.Value
+ if instr.index != nil {
+ // Otherwise the field is unknown to us and instr.op is an ignore op.
+ field = value.FieldByIndex(instr.index)
+ if field.Kind() == reflect.Ptr {
+ field = decAlloc(field)
+ }
+ }
+ instr.op(instr, state, field)
+ state.fieldnum = fieldnum
+ }
+}
+
+var noValue reflect.Value
+
+// ignoreStruct discards the data for a struct with no destination.
+func (dec *Decoder) ignoreStruct(engine *decEngine) {
+ state := dec.newDecoderState(&dec.buf)
+ defer dec.freeDecoderState(state)
+ state.fieldnum = -1
+ for state.b.Len() > 0 {
+ delta := int(state.decodeUint())
+ if delta < 0 {
+ errorf("ignore decode: corrupted data: negative delta")
+ }
+ if delta == 0 { // struct terminator is zero delta fieldnum
+ break
+ }
+ fieldnum := state.fieldnum + delta
+ if fieldnum >= len(engine.instr) {
+ error_(errRange)
+ }
+ instr := &engine.instr[fieldnum]
+ instr.op(instr, state, noValue)
+ state.fieldnum = fieldnum
+ }
+}
+
+// ignoreSingle discards the data for a top-level non-struct value with no
+// destination. It's used when calling Decode with a nil value.
+func (dec *Decoder) ignoreSingle(engine *decEngine) {
+ state := dec.newDecoderState(&dec.buf)
+ defer dec.freeDecoderState(state)
+ state.fieldnum = singletonField
+ delta := int(state.decodeUint())
+ if delta != 0 {
+ errorf("decode: corrupted data: non-zero delta for singleton")
+ }
+ instr := &engine.instr[singletonField]
+ instr.op(instr, state, noValue)
+}
+
+// decodeArrayHelper does the work for decoding arrays and slices.
+func (dec *Decoder) decodeArrayHelper(state *decoderState, value reflect.Value, elemOp decOp, length int, ovfl error, helper decHelper) {
+ if helper != nil && helper(state, value, length, ovfl) {
+ return
+ }
+ instr := &decInstr{elemOp, 0, nil, ovfl}
+ isPtr := value.Type().Elem().Kind() == reflect.Ptr
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding array or slice: length exceeds input size (%d elements)", length)
+ }
+ v := value.Index(i)
+ if isPtr {
+ v = decAlloc(v)
+ }
+ elemOp(instr, state, v)
+ }
+}
+
+// decodeArray decodes an array and stores it in value.
+// The length is an unsigned integer preceding the elements. Even though the length is redundant
+// (it's part of the type), it's a useful check and is included in the encoding.
+func (dec *Decoder) decodeArray(state *decoderState, value reflect.Value, elemOp decOp, length int, ovfl error, helper decHelper) {
+ if n := state.decodeUint(); n != uint64(length) {
+ errorf("length mismatch in decodeArray")
+ }
+ dec.decodeArrayHelper(state, value, elemOp, length, ovfl, helper)
+}
+
+// decodeIntoValue is a helper for map decoding.
+func decodeIntoValue(state *decoderState, op decOp, isPtr bool, value reflect.Value, instr *decInstr) reflect.Value {
+ v := value
+ if isPtr {
+ v = decAlloc(value)
+ }
+
+ op(instr, state, v)
+ return value
+}
+
+// decodeMap decodes a map and stores it in value.
+// Maps are encoded as a length followed by key:value pairs.
+// Because the internals of maps are not visible to us, we must
+// use reflection rather than pointer magic.
+func (dec *Decoder) decodeMap(mtyp reflect.Type, state *decoderState, value reflect.Value, keyOp, elemOp decOp, ovfl error) {
+ n := int(state.decodeUint())
+ if value.IsNil() {
+ value.Set(reflect.MakeMapWithSize(mtyp, n))
+ }
+ keyIsPtr := mtyp.Key().Kind() == reflect.Ptr
+ elemIsPtr := mtyp.Elem().Kind() == reflect.Ptr
+ keyInstr := &decInstr{keyOp, 0, nil, ovfl}
+ elemInstr := &decInstr{elemOp, 0, nil, ovfl}
+ keyP := reflect.New(mtyp.Key())
+ keyZ := reflect.Zero(mtyp.Key())
+ elemP := reflect.New(mtyp.Elem())
+ elemZ := reflect.Zero(mtyp.Elem())
+ for i := 0; i < n; i++ {
+ key := decodeIntoValue(state, keyOp, keyIsPtr, keyP.Elem(), keyInstr)
+ elem := decodeIntoValue(state, elemOp, elemIsPtr, elemP.Elem(), elemInstr)
+ value.SetMapIndex(key, elem)
+ keyP.Elem().Set(keyZ)
+ elemP.Elem().Set(elemZ)
+ }
+}
+
+// ignoreArrayHelper does the work for discarding arrays and slices.
+func (dec *Decoder) ignoreArrayHelper(state *decoderState, elemOp decOp, length int) {
+ instr := &decInstr{elemOp, 0, nil, errors.New("no error")}
+ for i := 0; i < length; i++ {
+ if state.b.Len() == 0 {
+ errorf("decoding array or slice: length exceeds input size (%d elements)", length)
+ }
+ elemOp(instr, state, noValue)
+ }
+}
+
+// ignoreArray discards the data for an array value with no destination.
+func (dec *Decoder) ignoreArray(state *decoderState, elemOp decOp, length int) {
+ if n := state.decodeUint(); n != uint64(length) {
+ errorf("length mismatch in ignoreArray")
+ }
+ dec.ignoreArrayHelper(state, elemOp, length)
+}
+
+// ignoreMap discards the data for a map value with no destination.
+func (dec *Decoder) ignoreMap(state *decoderState, keyOp, elemOp decOp) {
+ n := int(state.decodeUint())
+ keyInstr := &decInstr{keyOp, 0, nil, errors.New("no error")}
+ elemInstr := &decInstr{elemOp, 0, nil, errors.New("no error")}
+ for i := 0; i < n; i++ {
+ keyOp(keyInstr, state, noValue)
+ elemOp(elemInstr, state, noValue)
+ }
+}
+
+// decodeSlice decodes a slice and stores it in value.
+// Slices are encoded as an unsigned length followed by the elements.
+func (dec *Decoder) decodeSlice(state *decoderState, value reflect.Value, elemOp decOp, ovfl error, helper decHelper) {
+ u := state.decodeUint()
+ typ := value.Type()
+ size := uint64(typ.Elem().Size())
+ nBytes := u * size
+ n := int(u)
+ // Take care with overflow in this calculation.
+ if n < 0 || uint64(n) != u || nBytes > tooBig || (size > 0 && nBytes/size != u) {
+ // We don't check n against buffer length here because if it's a slice
+ // of interfaces, there will be buffer reloads.
+ errorf("%s slice too big: %d elements of %d bytes", typ.Elem(), u, size)
+ }
+ if value.Cap() < n {
+ value.Set(reflect.MakeSlice(typ, n, n))
+ } else {
+ value.Set(value.Slice(0, n))
+ }
+ dec.decodeArrayHelper(state, value, elemOp, n, ovfl, helper)
+}
+
+// ignoreSlice skips over the data for a slice value with no destination.
+func (dec *Decoder) ignoreSlice(state *decoderState, elemOp decOp) {
+ dec.ignoreArrayHelper(state, elemOp, int(state.decodeUint()))
+}
+
+// decodeInterface decodes an interface value and stores it in value.
+// Interfaces are encoded as the name of a concrete type followed by a value.
+// If the name is empty, the value is nil and no value is sent.
+func (dec *Decoder) decodeInterface(ityp reflect.Type, state *decoderState, value reflect.Value) {
+ // Read the name of the concrete type.
+ nr := state.decodeUint()
+ if nr > 1<<31 { // zero is permissible for anonymous types
+ errorf("invalid type name length %d", nr)
+ }
+ if nr > uint64(state.b.Len()) {
+ errorf("invalid type name length %d: exceeds input size", nr)
+ }
+ n := int(nr)
+ name := state.b.Bytes()[:n]
+ state.b.Drop(n)
+ // Allocate the destination interface value.
+ if len(name) == 0 {
+ // Copy the nil interface value to the target.
+ value.Set(reflect.Zero(value.Type()))
+ return
+ }
+ if len(name) > 1024 {
+ errorf("name too long (%d bytes): %.20q...", len(name), name)
+ }
+ // The concrete type must be registered.
+ typi, ok := nameToConcreteType.Load(string(name))
+ if !ok {
+ errorf("name not registered for interface: %q", name)
+ }
+ typ := typi.(reflect.Type)
+
+ // Read the type id of the concrete value.
+ concreteId := dec.decodeTypeSequence(true)
+ if concreteId < 0 {
+ error_(dec.err)
+ }
+ // Byte count of value is next; we don't care what it is (it's there
+ // in case we want to ignore the value by skipping it completely).
+ state.decodeUint()
+ // Read the concrete value.
+ v := allocValue(typ)
+ dec.decodeValue(concreteId, v)
+ if dec.err != nil {
+ error_(dec.err)
+ }
+ // Assign the concrete value to the interface.
+ // Tread carefully; it might not satisfy the interface.
+ if !typ.AssignableTo(ityp) {
+ errorf("%s is not assignable to type %s", typ, ityp)
+ }
+ // Copy the interface value to the target.
+ value.Set(v)
+}
+
+// ignoreInterface discards the data for an interface value with no destination.
+func (dec *Decoder) ignoreInterface(state *decoderState) {
+ // Read the name of the concrete type.
+ n, ok := state.getLength()
+ if !ok {
+ errorf("bad interface encoding: name too large for buffer")
+ }
+ bn := state.b.Len()
+ if bn < n {
+ errorf("invalid interface value length %d: exceeds input size %d", n, bn)
+ }
+ state.b.Drop(n)
+ id := dec.decodeTypeSequence(true)
+ if id < 0 {
+ error_(dec.err)
+ }
+ // At this point, the decoder buffer contains a delimited value. Just toss it.
+ n, ok = state.getLength()
+ if !ok {
+ errorf("bad interface encoding: data length too large for buffer")
+ }
+ state.b.Drop(n)
+}
+
+// decodeGobDecoder decodes something implementing the GobDecoder interface.
+// The data is encoded as a byte slice.
+func (dec *Decoder) decodeGobDecoder(ut *userTypeInfo, state *decoderState, value reflect.Value) {
+ // Read the bytes for the value.
+ n, ok := state.getLength()
+ if !ok {
+ errorf("GobDecoder: length too large for buffer")
+ }
+ b := state.b.Bytes()
+ if len(b) < n {
+ errorf("GobDecoder: invalid data length %d: exceeds input size %d", n, len(b))
+ }
+ b = b[:n]
+ state.b.Drop(n)
+ var err error
+ // We know it's one of these.
+ switch ut.externalDec {
+ case xGob:
+ err = value.Interface().(GobDecoder).GobDecode(b)
+ case xBinary:
+ err = value.Interface().(encoding.BinaryUnmarshaler).UnmarshalBinary(b)
+ case xText:
+ err = value.Interface().(encoding.TextUnmarshaler).UnmarshalText(b)
+ }
+ if err != nil {
+ error_(err)
+ }
+}
+
+// ignoreGobDecoder discards the data for a GobDecoder value with no destination.
+func (dec *Decoder) ignoreGobDecoder(state *decoderState) {
+ // Read the bytes for the value.
+ n, ok := state.getLength()
+ if !ok {
+ errorf("GobDecoder: length too large for buffer")
+ }
+ bn := state.b.Len()
+ if bn < n {
+ errorf("GobDecoder: invalid data length %d: exceeds input size %d", n, bn)
+ }
+ state.b.Drop(n)
+}
+
+// Index by Go types.
+var decOpTable = [...]decOp{
+ reflect.Bool: decBool,
+ reflect.Int8: decInt8,
+ reflect.Int16: decInt16,
+ reflect.Int32: decInt32,
+ reflect.Int64: decInt64,
+ reflect.Uint8: decUint8,
+ reflect.Uint16: decUint16,
+ reflect.Uint32: decUint32,
+ reflect.Uint64: decUint64,
+ reflect.Float32: decFloat32,
+ reflect.Float64: decFloat64,
+ reflect.Complex64: decComplex64,
+ reflect.Complex128: decComplex128,
+ reflect.String: decString,
+}
+
+// Indexed by gob types. tComplex will be added during type.init().
+var decIgnoreOpMap = map[typeId]decOp{
+ tBool: ignoreUint,
+ tInt: ignoreUint,
+ tUint: ignoreUint,
+ tFloat: ignoreUint,
+ tBytes: ignoreUint8Array,
+ tString: ignoreUint8Array,
+ tComplex: ignoreTwoUints,
+}
+
+// decOpFor returns the decoding op for the base type under rt and
+// the indirection count to reach it.
+func (dec *Decoder) decOpFor(wireId typeId, rt reflect.Type, name string, inProgress map[reflect.Type]*decOp) *decOp {
+ ut := userType(rt)
+ // If the type implements GobEncoder, we handle it without further processing.
+ if ut.externalDec != 0 {
+ return dec.gobDecodeOpFor(ut)
+ }
+
+ // If this type is already in progress, it's a recursive type (e.g. map[string]*T).
+ // Return the pointer to the op we're already building.
+ if opPtr := inProgress[rt]; opPtr != nil {
+ return opPtr
+ }
+ typ := ut.base
+ var op decOp
+ k := typ.Kind()
+ if int(k) < len(decOpTable) {
+ op = decOpTable[k]
+ }
+ if op == nil {
+ inProgress[rt] = &op
+ // Special cases
+ switch t := typ; t.Kind() {
+ case reflect.Array:
+ name = "element of " + name
+ elemId := dec.wireType[wireId].ArrayT.Elem
+ elemOp := dec.decOpFor(elemId, t.Elem(), name, inProgress)
+ ovfl := overflow(name)
+ helper := decArrayHelper[t.Elem().Kind()]
+ op = func(i *decInstr, state *decoderState, value reflect.Value) {
+ state.dec.decodeArray(state, value, *elemOp, t.Len(), ovfl, helper)
+ }
+
+ case reflect.Map:
+ keyId := dec.wireType[wireId].MapT.Key
+ elemId := dec.wireType[wireId].MapT.Elem
+ keyOp := dec.decOpFor(keyId, t.Key(), "key of "+name, inProgress)
+ elemOp := dec.decOpFor(elemId, t.Elem(), "element of "+name, inProgress)
+ ovfl := overflow(name)
+ op = func(i *decInstr, state *decoderState, value reflect.Value) {
+ state.dec.decodeMap(t, state, value, *keyOp, *elemOp, ovfl)
+ }
+
+ case reflect.Slice:
+ name = "element of " + name
+ if t.Elem().Kind() == reflect.Uint8 {
+ op = decUint8Slice
+ break
+ }
+ var elemId typeId
+ if tt, ok := builtinIdToType[wireId]; ok {
+ elemId = tt.(*sliceType).Elem
+ } else {
+ elemId = dec.wireType[wireId].SliceT.Elem
+ }
+ elemOp := dec.decOpFor(elemId, t.Elem(), name, inProgress)
+ ovfl := overflow(name)
+ helper := decSliceHelper[t.Elem().Kind()]
+ op = func(i *decInstr, state *decoderState, value reflect.Value) {
+ state.dec.decodeSlice(state, value, *elemOp, ovfl, helper)
+ }
+
+ case reflect.Struct:
+ // Generate a closure that calls out to the engine for the nested type.
+ ut := userType(typ)
+ enginePtr, err := dec.getDecEnginePtr(wireId, ut)
+ if err != nil {
+ error_(err)
+ }
+ op = func(i *decInstr, state *decoderState, value reflect.Value) {
+ // indirect through enginePtr to delay evaluation for recursive structs.
+ dec.decodeStruct(*enginePtr, value)
+ }
+ case reflect.Interface:
+ op = func(i *decInstr, state *decoderState, value reflect.Value) {
+ state.dec.decodeInterface(t, state, value)
+ }
+ }
+ }
+ if op == nil {
+ errorf("decode can't handle type %s", rt)
+ }
+ return &op
+}
+
+var maxIgnoreNestingDepth = 10000
+
+// decIgnoreOpFor returns the decoding op for a field that has no destination.
+func (dec *Decoder) decIgnoreOpFor(wireId typeId, inProgress map[typeId]*decOp, depth int) *decOp {
+ if depth > maxIgnoreNestingDepth {
+ error_(errors.New("invalid nesting depth"))
+ }
+ // If this type is already in progress, it's a recursive type (e.g. map[string]*T).
+ // Return the pointer to the op we're already building.
+ if opPtr := inProgress[wireId]; opPtr != nil {
+ return opPtr
+ }
+ op, ok := decIgnoreOpMap[wireId]
+ if !ok {
+ inProgress[wireId] = &op
+ if wireId == tInterface {
+ // Special case because it's a method: the ignored item might
+ // define types and we need to record their state in the decoder.
+ op = func(i *decInstr, state *decoderState, value reflect.Value) {
+ state.dec.ignoreInterface(state)
+ }
+ return &op
+ }
+ // Special cases
+ wire := dec.wireType[wireId]
+ switch {
+ case wire == nil:
+ errorf("bad data: undefined type %s", wireId.string())
+ case wire.ArrayT != nil:
+ elemId := wire.ArrayT.Elem
+ elemOp := dec.decIgnoreOpFor(elemId, inProgress, depth+1)
+ op = func(i *decInstr, state *decoderState, value reflect.Value) {
+ state.dec.ignoreArray(state, *elemOp, wire.ArrayT.Len)
+ }
+
+ case wire.MapT != nil:
+ keyId := dec.wireType[wireId].MapT.Key
+ elemId := dec.wireType[wireId].MapT.Elem
+ keyOp := dec.decIgnoreOpFor(keyId, inProgress, depth+1)
+ elemOp := dec.decIgnoreOpFor(elemId, inProgress, depth+1)
+ op = func(i *decInstr, state *decoderState, value reflect.Value) {
+ state.dec.ignoreMap(state, *keyOp, *elemOp)
+ }
+
+ case wire.SliceT != nil:
+ elemId := wire.SliceT.Elem
+ elemOp := dec.decIgnoreOpFor(elemId, inProgress, depth+1)
+ op = func(i *decInstr, state *decoderState, value reflect.Value) {
+ state.dec.ignoreSlice(state, *elemOp)
+ }
+
+ case wire.StructT != nil:
+ // Generate a closure that calls out to the engine for the nested type.
+ enginePtr, err := dec.getIgnoreEnginePtr(wireId)
+ if err != nil {
+ error_(err)
+ }
+ op = func(i *decInstr, state *decoderState, value reflect.Value) {
+ // indirect through enginePtr to delay evaluation for recursive structs
+ state.dec.ignoreStruct(*enginePtr)
+ }
+
+ case wire.GobEncoderT != nil, wire.BinaryMarshalerT != nil, wire.TextMarshalerT != nil:
+ op = func(i *decInstr, state *decoderState, value reflect.Value) {
+ state.dec.ignoreGobDecoder(state)
+ }
+ }
+ }
+ if op == nil {
+ errorf("bad data: ignore can't handle type %s", wireId.string())
+ }
+ return &op
+}
+
+// gobDecodeOpFor returns the op for a type that is known to implement
+// GobDecoder.
+func (dec *Decoder) gobDecodeOpFor(ut *userTypeInfo) *decOp {
+ rcvrType := ut.user
+ if ut.decIndir == -1 {
+ rcvrType = reflect.PtrTo(rcvrType)
+ } else if ut.decIndir > 0 {
+ for i := int8(0); i < ut.decIndir; i++ {
+ rcvrType = rcvrType.Elem()
+ }
+ }
+ var op decOp
+ op = func(i *decInstr, state *decoderState, value reflect.Value) {
+ // We now have the base type. We need its address if the receiver is a pointer.
+ if value.Kind() != reflect.Ptr && rcvrType.Kind() == reflect.Ptr {
+ value = value.Addr()
+ }
+ state.dec.decodeGobDecoder(ut, state, value)
+ }
+ return &op
+}
+
+// compatibleType asks: Are these two gob Types compatible?
+// Answers the question for basic types, arrays, maps and slices, plus
+// GobEncoder/Decoder pairs.
+// Structs are considered ok; fields will be checked later.
+func (dec *Decoder) compatibleType(fr reflect.Type, fw typeId, inProgress map[reflect.Type]typeId) bool {
+ if rhs, ok := inProgress[fr]; ok {
+ return rhs == fw
+ }
+ inProgress[fr] = fw
+ ut := userType(fr)
+ wire, ok := dec.wireType[fw]
+ // If wire was encoded with an encoding method, fr must have that method.
+ // And if not, it must not.
+ // At most one of the booleans in ut is set.
+ // We could possibly relax this constraint in the future in order to
+ // choose the decoding method using the data in the wireType.
+ // The parentheses look odd but are correct.
+ if (ut.externalDec == xGob) != (ok && wire.GobEncoderT != nil) ||
+ (ut.externalDec == xBinary) != (ok && wire.BinaryMarshalerT != nil) ||
+ (ut.externalDec == xText) != (ok && wire.TextMarshalerT != nil) {
+ return false
+ }
+ if ut.externalDec != 0 { // This test trumps all others.
+ return true
+ }
+ switch t := ut.base; t.Kind() {
+ default:
+ // chan, etc: cannot handle.
+ return false
+ case reflect.Bool:
+ return fw == tBool
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ return fw == tInt
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ return fw == tUint
+ case reflect.Float32, reflect.Float64:
+ return fw == tFloat
+ case reflect.Complex64, reflect.Complex128:
+ return fw == tComplex
+ case reflect.String:
+ return fw == tString
+ case reflect.Interface:
+ return fw == tInterface
+ case reflect.Array:
+ if !ok || wire.ArrayT == nil {
+ return false
+ }
+ array := wire.ArrayT
+ return t.Len() == array.Len && dec.compatibleType(t.Elem(), array.Elem, inProgress)
+ case reflect.Map:
+ if !ok || wire.MapT == nil {
+ return false
+ }
+ MapType := wire.MapT
+ return dec.compatibleType(t.Key(), MapType.Key, inProgress) && dec.compatibleType(t.Elem(), MapType.Elem, inProgress)
+ case reflect.Slice:
+ // Is it an array of bytes?
+ if t.Elem().Kind() == reflect.Uint8 {
+ return fw == tBytes
+ }
+ // Extract and compare element types.
+ var sw *sliceType
+ if tt, ok := builtinIdToType[fw]; ok {
+ sw, _ = tt.(*sliceType)
+ } else if wire != nil {
+ sw = wire.SliceT
+ }
+ elem := userType(t.Elem()).base
+ return sw != nil && dec.compatibleType(elem, sw.Elem, inProgress)
+ case reflect.Struct:
+ return true
+ }
+}
+
+// typeString returns a human-readable description of the type identified by remoteId.
+func (dec *Decoder) typeString(remoteId typeId) string {
+ typeLock.Lock()
+ defer typeLock.Unlock()
+ if t := idToType[remoteId]; t != nil {
+ // globally known type.
+ return t.string()
+ }
+ return dec.wireType[remoteId].string()
+}
+
+// compileSingle compiles the decoder engine for a non-struct top-level value, including
+// GobDecoders.
+func (dec *Decoder) compileSingle(remoteId typeId, ut *userTypeInfo) (engine *decEngine, err error) {
+ rt := ut.user
+ engine = new(decEngine)
+ engine.instr = make([]decInstr, 1) // one item
+ name := rt.String() // best we can do
+ if !dec.compatibleType(rt, remoteId, make(map[reflect.Type]typeId)) {
+ remoteType := dec.typeString(remoteId)
+ // Common confusing case: local interface type, remote concrete type.
+ if ut.base.Kind() == reflect.Interface && remoteId != tInterface {
+ return nil, errors.New("gob: local interface type " + name + " can only be decoded from remote interface type; received concrete type " + remoteType)
+ }
+ return nil, errors.New("gob: decoding into local type " + name + ", received remote type " + remoteType)
+ }
+ op := dec.decOpFor(remoteId, rt, name, make(map[reflect.Type]*decOp))
+ ovfl := errors.New(`value for "` + name + `" out of range`)
+ engine.instr[singletonField] = decInstr{*op, singletonField, nil, ovfl}
+ engine.numInstr = 1
+ return
+}
+
+// compileIgnoreSingle compiles the decoder engine for a non-struct top-level value that will be discarded.
+func (dec *Decoder) compileIgnoreSingle(remoteId typeId) *decEngine {
+ engine := new(decEngine)
+ engine.instr = make([]decInstr, 1) // one item
+ op := dec.decIgnoreOpFor(remoteId, make(map[typeId]*decOp), 0)
+ ovfl := overflow(dec.typeString(remoteId))
+ engine.instr[0] = decInstr{*op, 0, nil, ovfl}
+ engine.numInstr = 1
+ return engine
+}
+
+// compileDec compiles the decoder engine for a value. If the value is not a struct,
+// it calls out to compileSingle.
+func (dec *Decoder) compileDec(remoteId typeId, ut *userTypeInfo) (engine *decEngine, err error) {
+ defer catchError(&err)
+ rt := ut.base
+ srt := rt
+ if srt.Kind() != reflect.Struct || ut.externalDec != 0 {
+ return dec.compileSingle(remoteId, ut)
+ }
+ var wireStruct *structType
+ // Builtin types can come from global pool; the rest must be defined by the decoder.
+ // Also we know we're decoding a struct now, so the client must have sent one.
+ if t, ok := builtinIdToType[remoteId]; ok {
+ wireStruct, _ = t.(*structType)
+ } else {
+ wire := dec.wireType[remoteId]
+ if wire == nil {
+ error_(errBadType)
+ }
+ wireStruct = wire.StructT
+ }
+ if wireStruct == nil {
+ errorf("type mismatch in decoder: want struct type %s; got non-struct", rt)
+ }
+ engine = new(decEngine)
+ engine.instr = make([]decInstr, len(wireStruct.Field))
+ seen := make(map[reflect.Type]*decOp)
+ // Loop over the fields of the wire type.
+ for fieldnum := 0; fieldnum < len(wireStruct.Field); fieldnum++ {
+ wireField := wireStruct.Field[fieldnum]
+ if wireField.Name == "" {
+ errorf("empty name for remote field of type %s", wireStruct.Name)
+ }
+ ovfl := overflow(wireField.Name)
+ // Find the field of the local type with the same name.
+ localField, present := srt.FieldByName(wireField.Name)
+ // TODO(r): anonymous names
+ if !present || !isExported(wireField.Name) {
+ op := dec.decIgnoreOpFor(wireField.Id, make(map[typeId]*decOp), 0)
+ engine.instr[fieldnum] = decInstr{*op, fieldnum, nil, ovfl}
+ continue
+ }
+ if !dec.compatibleType(localField.Type, wireField.Id, make(map[reflect.Type]typeId)) {
+ errorf("wrong type (%s) for received field %s.%s", localField.Type, wireStruct.Name, wireField.Name)
+ }
+ op := dec.decOpFor(wireField.Id, localField.Type, localField.Name, seen)
+ engine.instr[fieldnum] = decInstr{*op, fieldnum, localField.Index, ovfl}
+ engine.numInstr++
+ }
+ return
+}
+
+// getDecEnginePtr returns the engine for the specified type.
+func (dec *Decoder) getDecEnginePtr(remoteId typeId, ut *userTypeInfo) (enginePtr **decEngine, err error) {
+ rt := ut.user
+ decoderMap, ok := dec.decoderCache[rt]
+ if !ok {
+ decoderMap = make(map[typeId]**decEngine)
+ dec.decoderCache[rt] = decoderMap
+ }
+ if enginePtr, ok = decoderMap[remoteId]; !ok {
+ // To handle recursive types, mark this engine as underway before compiling.
+ enginePtr = new(*decEngine)
+ decoderMap[remoteId] = enginePtr
+ *enginePtr, err = dec.compileDec(remoteId, ut)
+ if err != nil {
+ delete(decoderMap, remoteId)
+ }
+ }
+ return
+}
+
+// emptyStruct is the type we compile into when ignoring a struct value.
+type emptyStruct struct{}
+
+var emptyStructType = reflect.TypeOf(emptyStruct{})
+
+// getIgnoreEnginePtr returns the engine for the specified type when the value is to be discarded.
+func (dec *Decoder) getIgnoreEnginePtr(wireId typeId) (enginePtr **decEngine, err error) {
+ var ok bool
+ if enginePtr, ok = dec.ignorerCache[wireId]; !ok {
+ // To handle recursive types, mark this engine as underway before compiling.
+ enginePtr = new(*decEngine)
+ dec.ignorerCache[wireId] = enginePtr
+ wire := dec.wireType[wireId]
+ if wire != nil && wire.StructT != nil {
+ *enginePtr, err = dec.compileDec(wireId, userType(emptyStructType))
+ } else {
+ *enginePtr = dec.compileIgnoreSingle(wireId)
+ }
+ if err != nil {
+ delete(dec.ignorerCache, wireId)
+ }
+ }
+ return
+}
+
+// decodeValue decodes the data stream representing a value and stores it in value.
+func (dec *Decoder) decodeValue(wireId typeId, value reflect.Value) {
+ defer catchError(&dec.err)
+ // If the value is nil, it means we should just ignore this item.
+ if !value.IsValid() {
+ dec.decodeIgnoredValue(wireId)
+ return
+ }
+ // Dereference down to the underlying type.
+ ut := userType(value.Type())
+ base := ut.base
+ var enginePtr **decEngine
+ enginePtr, dec.err = dec.getDecEnginePtr(wireId, ut)
+ if dec.err != nil {
+ return
+ }
+ value = decAlloc(value)
+ engine := *enginePtr
+ if st := base; st.Kind() == reflect.Struct && ut.externalDec == 0 {
+ wt := dec.wireType[wireId]
+ if engine.numInstr == 0 && st.NumField() > 0 &&
+ wt != nil && len(wt.StructT.Field) > 0 {
+ name := base.Name()
+ errorf("type mismatch: no fields matched compiling decoder for %s", name)
+ }
+ dec.decodeStruct(engine, value)
+ } else {
+ dec.decodeSingle(engine, value)
+ }
+}
+
+// decodeIgnoredValue decodes the data stream representing a value of the specified type and discards it.
+func (dec *Decoder) decodeIgnoredValue(wireId typeId) {
+ var enginePtr **decEngine
+ enginePtr, dec.err = dec.getIgnoreEnginePtr(wireId)
+ if dec.err != nil {
+ return
+ }
+ wire := dec.wireType[wireId]
+ if wire != nil && wire.StructT != nil {
+ dec.ignoreStruct(*enginePtr)
+ } else {
+ dec.ignoreSingle(*enginePtr)
+ }
+}
+
+func init() {
+ var iop, uop decOp
+ switch reflect.TypeOf(int(0)).Bits() {
+ case 32:
+ iop = decInt32
+ uop = decUint32
+ case 64:
+ iop = decInt64
+ uop = decUint64
+ default:
+ panic("gob: unknown size of int/uint")
+ }
+ decOpTable[reflect.Int] = iop
+ decOpTable[reflect.Uint] = uop
+
+ // Finally uintptr
+ switch reflect.TypeOf(uintptr(0)).Bits() {
+ case 32:
+ uop = decUint32
+ case 64:
+ uop = decUint64
+ default:
+ panic("gob: unknown size of uintptr")
+ }
+ decOpTable[reflect.Uintptr] = uop
+}
+
+// Gob depends on being able to take the address
+// of zeroed Values it creates, so use this wrapper instead
+// of the standard reflect.Zero.
+// Each call allocates once.
+func allocValue(t reflect.Type) reflect.Value {
+ return reflect.New(t).Elem()
+}
diff --git a/src/encoding/gob/decoder.go b/src/encoding/gob/decoder.go
new file mode 100644
index 0000000..b476aaa
--- /dev/null
+++ b/src/encoding/gob/decoder.go
@@ -0,0 +1,224 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gob
+
+import (
+ "bufio"
+ "errors"
+ "io"
+ "reflect"
+ "sync"
+)
+
+// tooBig provides a sanity check for sizes; used in several places. Upper limit
+// of is 1GB on 32-bit systems, 8GB on 64-bit, allowing room to grow a little
+// without overflow.
+const tooBig = (1 << 30) << (^uint(0) >> 62)
+
+// A Decoder manages the receipt of type and data information read from the
+// remote side of a connection. It is safe for concurrent use by multiple
+// goroutines.
+//
+// The Decoder does only basic sanity checking on decoded input sizes,
+// and its limits are not configurable. Take caution when decoding gob data
+// from untrusted sources.
+type Decoder struct {
+ mutex sync.Mutex // each item must be received atomically
+ r io.Reader // source of the data
+ buf decBuffer // buffer for more efficient i/o from r
+ wireType map[typeId]*wireType // map from remote ID to local description
+ decoderCache map[reflect.Type]map[typeId]**decEngine // cache of compiled engines
+ ignorerCache map[typeId]**decEngine // ditto for ignored objects
+ freeList *decoderState // list of free decoderStates; avoids reallocation
+ countBuf []byte // used for decoding integers while parsing messages
+ err error
+}
+
+// NewDecoder returns a new decoder that reads from the io.Reader.
+// If r does not also implement io.ByteReader, it will be wrapped in a
+// bufio.Reader.
+func NewDecoder(r io.Reader) *Decoder {
+ dec := new(Decoder)
+ // We use the ability to read bytes as a plausible surrogate for buffering.
+ if _, ok := r.(io.ByteReader); !ok {
+ r = bufio.NewReader(r)
+ }
+ dec.r = r
+ dec.wireType = make(map[typeId]*wireType)
+ dec.decoderCache = make(map[reflect.Type]map[typeId]**decEngine)
+ dec.ignorerCache = make(map[typeId]**decEngine)
+ dec.countBuf = make([]byte, 9) // counts may be uint64s (unlikely!), require 9 bytes
+
+ return dec
+}
+
+// recvType loads the definition of a type.
+func (dec *Decoder) recvType(id typeId) {
+ // Have we already seen this type? That's an error
+ if id < firstUserId || dec.wireType[id] != nil {
+ dec.err = errors.New("gob: duplicate type received")
+ return
+ }
+
+ // Type:
+ wire := new(wireType)
+ dec.decodeValue(tWireType, reflect.ValueOf(wire))
+ if dec.err != nil {
+ return
+ }
+ // Remember we've seen this type.
+ dec.wireType[id] = wire
+}
+
+var errBadCount = errors.New("invalid message length")
+
+// recvMessage reads the next count-delimited item from the input. It is the converse
+// of Encoder.writeMessage. It returns false on EOF or other error reading the message.
+func (dec *Decoder) recvMessage() bool {
+ // Read a count.
+ nbytes, _, err := decodeUintReader(dec.r, dec.countBuf)
+ if err != nil {
+ dec.err = err
+ return false
+ }
+ if nbytes >= tooBig {
+ dec.err = errBadCount
+ return false
+ }
+ dec.readMessage(int(nbytes))
+ return dec.err == nil
+}
+
+// readMessage reads the next nbytes bytes from the input.
+func (dec *Decoder) readMessage(nbytes int) {
+ if dec.buf.Len() != 0 {
+ // The buffer should always be empty now.
+ panic("non-empty decoder buffer")
+ }
+ // Read the data
+ dec.buf.Size(nbytes)
+ _, dec.err = io.ReadFull(dec.r, dec.buf.Bytes())
+ if dec.err == io.EOF {
+ dec.err = io.ErrUnexpectedEOF
+ }
+}
+
+// toInt turns an encoded uint64 into an int, according to the marshaling rules.
+func toInt(x uint64) int64 {
+ i := int64(x >> 1)
+ if x&1 != 0 {
+ i = ^i
+ }
+ return i
+}
+
+func (dec *Decoder) nextInt() int64 {
+ n, _, err := decodeUintReader(&dec.buf, dec.countBuf)
+ if err != nil {
+ dec.err = err
+ }
+ return toInt(n)
+}
+
+func (dec *Decoder) nextUint() uint64 {
+ n, _, err := decodeUintReader(&dec.buf, dec.countBuf)
+ if err != nil {
+ dec.err = err
+ }
+ return n
+}
+
+// decodeTypeSequence parses:
+// TypeSequence
+// (TypeDefinition DelimitedTypeDefinition*)?
+// and returns the type id of the next value. It returns -1 at
+// EOF. Upon return, the remainder of dec.buf is the value to be
+// decoded. If this is an interface value, it can be ignored by
+// resetting that buffer.
+func (dec *Decoder) decodeTypeSequence(isInterface bool) typeId {
+ for dec.err == nil {
+ if dec.buf.Len() == 0 {
+ if !dec.recvMessage() {
+ break
+ }
+ }
+ // Receive a type id.
+ id := typeId(dec.nextInt())
+ if id >= 0 {
+ // Value follows.
+ return id
+ }
+ // Type definition for (-id) follows.
+ dec.recvType(-id)
+ if dec.err != nil {
+ break
+ }
+ // When decoding an interface, after a type there may be a
+ // DelimitedValue still in the buffer. Skip its count.
+ // (Alternatively, the buffer is empty and the byte count
+ // will be absorbed by recvMessage.)
+ if dec.buf.Len() > 0 {
+ if !isInterface {
+ dec.err = errors.New("extra data in buffer")
+ break
+ }
+ dec.nextUint()
+ }
+ }
+ return -1
+}
+
+// Decode reads the next value from the input stream and stores
+// it in the data represented by the empty interface value.
+// If e is nil, the value will be discarded. Otherwise,
+// the value underlying e must be a pointer to the
+// correct type for the next data item received.
+// If the input is at EOF, Decode returns io.EOF and
+// does not modify e.
+func (dec *Decoder) Decode(e interface{}) error {
+ if e == nil {
+ return dec.DecodeValue(reflect.Value{})
+ }
+ value := reflect.ValueOf(e)
+ // If e represents a value as opposed to a pointer, the answer won't
+ // get back to the caller. Make sure it's a pointer.
+ if value.Type().Kind() != reflect.Ptr {
+ dec.err = errors.New("gob: attempt to decode into a non-pointer")
+ return dec.err
+ }
+ return dec.DecodeValue(value)
+}
+
+// DecodeValue reads the next value from the input stream.
+// If v is the zero reflect.Value (v.Kind() == Invalid), DecodeValue discards the value.
+// Otherwise, it stores the value into v. In that case, v must represent
+// a non-nil pointer to data or be an assignable reflect.Value (v.CanSet())
+// If the input is at EOF, DecodeValue returns io.EOF and
+// does not modify v.
+func (dec *Decoder) DecodeValue(v reflect.Value) error {
+ if v.IsValid() {
+ if v.Kind() == reflect.Ptr && !v.IsNil() {
+ // That's okay, we'll store through the pointer.
+ } else if !v.CanSet() {
+ return errors.New("gob: DecodeValue of unassignable value")
+ }
+ }
+ // Make sure we're single-threaded through here.
+ dec.mutex.Lock()
+ defer dec.mutex.Unlock()
+
+ dec.buf.Reset() // In case data lingers from previous invocation.
+ dec.err = nil
+ id := dec.decodeTypeSequence(false)
+ if dec.err == nil {
+ dec.decodeValue(id, v)
+ }
+ return dec.err
+}
+
+// If debug.go is compiled into the program, debugFunc prints a human-readable
+// representation of the gob data read from r by calling that file's Debug function.
+// Otherwise it is nil.
+var debugFunc func(io.Reader)
diff --git a/src/encoding/gob/doc.go b/src/encoding/gob/doc.go
new file mode 100644
index 0000000..c765707
--- /dev/null
+++ b/src/encoding/gob/doc.go
@@ -0,0 +1,415 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package gob manages streams of gobs - binary values exchanged between an
+Encoder (transmitter) and a Decoder (receiver). A typical use is transporting
+arguments and results of remote procedure calls (RPCs) such as those provided by
+package "net/rpc".
+
+The implementation compiles a custom codec for each data type in the stream and
+is most efficient when a single Encoder is used to transmit a stream of values,
+amortizing the cost of compilation.
+
+Basics
+
+A stream of gobs is self-describing. Each data item in the stream is preceded by
+a specification of its type, expressed in terms of a small set of predefined
+types. Pointers are not transmitted, but the things they point to are
+transmitted; that is, the values are flattened. Nil pointers are not permitted,
+as they have no value. Recursive types work fine, but
+recursive values (data with cycles) are problematic. This may change.
+
+To use gobs, create an Encoder and present it with a series of data items as
+values or addresses that can be dereferenced to values. The Encoder makes sure
+all type information is sent before it is needed. At the receive side, a
+Decoder retrieves values from the encoded stream and unpacks them into local
+variables.
+
+Types and Values
+
+The source and destination values/types need not correspond exactly. For structs,
+fields (identified by name) that are in the source but absent from the receiving
+variable will be ignored. Fields that are in the receiving variable but missing
+from the transmitted type or value will be ignored in the destination. If a field
+with the same name is present in both, their types must be compatible. Both the
+receiver and transmitter will do all necessary indirection and dereferencing to
+convert between gobs and actual Go values. For instance, a gob type that is
+schematically,
+
+ struct { A, B int }
+
+can be sent from or received into any of these Go types:
+
+ struct { A, B int } // the same
+ *struct { A, B int } // extra indirection of the struct
+ struct { *A, **B int } // extra indirection of the fields
+ struct { A, B int64 } // different concrete value type; see below
+
+It may also be received into any of these:
+
+ struct { A, B int } // the same
+ struct { B, A int } // ordering doesn't matter; matching is by name
+ struct { A, B, C int } // extra field (C) ignored
+ struct { B int } // missing field (A) ignored; data will be dropped
+ struct { B, C int } // missing field (A) ignored; extra field (C) ignored.
+
+Attempting to receive into these types will draw a decode error:
+
+ struct { A int; B uint } // change of signedness for B
+ struct { A int; B float } // change of type for B
+ struct { } // no field names in common
+ struct { C, D int } // no field names in common
+
+Integers are transmitted two ways: arbitrary precision signed integers or
+arbitrary precision unsigned integers. There is no int8, int16 etc.
+discrimination in the gob format; there are only signed and unsigned integers. As
+described below, the transmitter sends the value in a variable-length encoding;
+the receiver accepts the value and stores it in the destination variable.
+Floating-point numbers are always sent using IEEE-754 64-bit precision (see
+below).
+
+Signed integers may be received into any signed integer variable: int, int16, etc.;
+unsigned integers may be received into any unsigned integer variable; and floating
+point values may be received into any floating point variable. However,
+the destination variable must be able to represent the value or the decode
+operation will fail.
+
+Structs, arrays and slices are also supported. Structs encode and decode only
+exported fields. Strings and arrays of bytes are supported with a special,
+efficient representation (see below). When a slice is decoded, if the existing
+slice has capacity the slice will be extended in place; if not, a new array is
+allocated. Regardless, the length of the resulting slice reports the number of
+elements decoded.
+
+In general, if allocation is required, the decoder will allocate memory. If not,
+it will update the destination variables with values read from the stream. It does
+not initialize them first, so if the destination is a compound value such as a
+map, struct, or slice, the decoded values will be merged elementwise into the
+existing variables.
+
+Functions and channels will not be sent in a gob. Attempting to encode such a value
+at the top level will fail. A struct field of chan or func type is treated exactly
+like an unexported field and is ignored.
+
+Gob can encode a value of any type implementing the GobEncoder or
+encoding.BinaryMarshaler interfaces by calling the corresponding method,
+in that order of preference.
+
+Gob can decode a value of any type implementing the GobDecoder or
+encoding.BinaryUnmarshaler interfaces by calling the corresponding method,
+again in that order of preference.
+
+Encoding Details
+
+This section documents the encoding, details that are not important for most
+users. Details are presented bottom-up.
+
+An unsigned integer is sent one of two ways. If it is less than 128, it is sent
+as a byte with that value. Otherwise it is sent as a minimal-length big-endian
+(high byte first) byte stream holding the value, preceded by one byte holding the
+byte count, negated. Thus 0 is transmitted as (00), 7 is transmitted as (07) and
+256 is transmitted as (FE 01 00).
+
+A boolean is encoded within an unsigned integer: 0 for false, 1 for true.
+
+A signed integer, i, is encoded within an unsigned integer, u. Within u, bits 1
+upward contain the value; bit 0 says whether they should be complemented upon
+receipt. The encode algorithm looks like this:
+
+ var u uint
+ if i < 0 {
+ u = (^uint(i) << 1) | 1 // complement i, bit 0 is 1
+ } else {
+ u = (uint(i) << 1) // do not complement i, bit 0 is 0
+ }
+ encodeUnsigned(u)
+
+The low bit is therefore analogous to a sign bit, but making it the complement bit
+instead guarantees that the largest negative integer is not a special case. For
+example, -129=^128=(^256>>1) encodes as (FE 01 01).
+
+Floating-point numbers are always sent as a representation of a float64 value.
+That value is converted to a uint64 using math.Float64bits. The uint64 is then
+byte-reversed and sent as a regular unsigned integer. The byte-reversal means the
+exponent and high-precision part of the mantissa go first. Since the low bits are
+often zero, this can save encoding bytes. For instance, 17.0 is encoded in only
+three bytes (FE 31 40).
+
+Strings and slices of bytes are sent as an unsigned count followed by that many
+uninterpreted bytes of the value.
+
+All other slices and arrays are sent as an unsigned count followed by that many
+elements using the standard gob encoding for their type, recursively.
+
+Maps are sent as an unsigned count followed by that many key, element
+pairs. Empty but non-nil maps are sent, so if the receiver has not allocated
+one already, one will always be allocated on receipt unless the transmitted map
+is nil and not at the top level.
+
+In slices and arrays, as well as maps, all elements, even zero-valued elements,
+are transmitted, even if all the elements are zero.
+
+Structs are sent as a sequence of (field number, field value) pairs. The field
+value is sent using the standard gob encoding for its type, recursively. If a
+field has the zero value for its type (except for arrays; see above), it is omitted
+from the transmission. The field number is defined by the type of the encoded
+struct: the first field of the encoded type is field 0, the second is field 1,
+etc. When encoding a value, the field numbers are delta encoded for efficiency
+and the fields are always sent in order of increasing field number; the deltas are
+therefore unsigned. The initialization for the delta encoding sets the field
+number to -1, so an unsigned integer field 0 with value 7 is transmitted as unsigned
+delta = 1, unsigned value = 7 or (01 07). Finally, after all the fields have been
+sent a terminating mark denotes the end of the struct. That mark is a delta=0
+value, which has representation (00).
+
+Interface types are not checked for compatibility; all interface types are
+treated, for transmission, as members of a single "interface" type, analogous to
+int or []byte - in effect they're all treated as interface{}. Interface values
+are transmitted as a string identifying the concrete type being sent (a name
+that must be pre-defined by calling Register), followed by a byte count of the
+length of the following data (so the value can be skipped if it cannot be
+stored), followed by the usual encoding of concrete (dynamic) value stored in
+the interface value. (A nil interface value is identified by the empty string
+and transmits no value.) Upon receipt, the decoder verifies that the unpacked
+concrete item satisfies the interface of the receiving variable.
+
+If a value is passed to Encode and the type is not a struct (or pointer to struct,
+etc.), for simplicity of processing it is represented as a struct of one field.
+The only visible effect of this is to encode a zero byte after the value, just as
+after the last field of an encoded struct, so that the decode algorithm knows when
+the top-level value is complete.
+
+The representation of types is described below. When a type is defined on a given
+connection between an Encoder and Decoder, it is assigned a signed integer type
+id. When Encoder.Encode(v) is called, it makes sure there is an id assigned for
+the type of v and all its elements and then it sends the pair (typeid, encoded-v)
+where typeid is the type id of the encoded type of v and encoded-v is the gob
+encoding of the value v.
+
+To define a type, the encoder chooses an unused, positive type id and sends the
+pair (-type id, encoded-type) where encoded-type is the gob encoding of a wireType
+description, constructed from these types:
+
+ type wireType struct {
+ ArrayT *ArrayType
+ SliceT *SliceType
+ StructT *StructType
+ MapT *MapType
+ GobEncoderT *gobEncoderType
+ BinaryMarshalerT *gobEncoderType
+ TextMarshalerT *gobEncoderType
+
+ }
+ type arrayType struct {
+ CommonType
+ Elem typeId
+ Len int
+ }
+ type CommonType struct {
+ Name string // the name of the struct type
+ Id int // the id of the type, repeated so it's inside the type
+ }
+ type sliceType struct {
+ CommonType
+ Elem typeId
+ }
+ type structType struct {
+ CommonType
+ Field []*fieldType // the fields of the struct.
+ }
+ type fieldType struct {
+ Name string // the name of the field.
+ Id int // the type id of the field, which must be already defined
+ }
+ type mapType struct {
+ CommonType
+ Key typeId
+ Elem typeId
+ }
+ type gobEncoderType struct {
+ CommonType
+ }
+
+If there are nested type ids, the types for all inner type ids must be defined
+before the top-level type id is used to describe an encoded-v.
+
+For simplicity in setup, the connection is defined to understand these types a
+priori, as well as the basic gob types int, uint, etc. Their ids are:
+
+ bool 1
+ int 2
+ uint 3
+ float 4
+ []byte 5
+ string 6
+ complex 7
+ interface 8
+ // gap for reserved ids.
+ WireType 16
+ ArrayType 17
+ CommonType 18
+ SliceType 19
+ StructType 20
+ FieldType 21
+ // 22 is slice of fieldType.
+ MapType 23
+
+Finally, each message created by a call to Encode is preceded by an encoded
+unsigned integer count of the number of bytes remaining in the message. After
+the initial type name, interface values are wrapped the same way; in effect, the
+interface value acts like a recursive invocation of Encode.
+
+In summary, a gob stream looks like
+
+ (byteCount (-type id, encoding of a wireType)* (type id, encoding of a value))*
+
+where * signifies zero or more repetitions and the type id of a value must
+be predefined or be defined before the value in the stream.
+
+Compatibility: Any future changes to the package will endeavor to maintain
+compatibility with streams encoded using previous versions. That is, any released
+version of this package should be able to decode data written with any previously
+released version, subject to issues such as security fixes. See the Go compatibility
+document for background: https://golang.org/doc/go1compat
+
+See "Gobs of data" for a design discussion of the gob wire format:
+https://blog.golang.org/gobs-of-data
+*/
+package gob
+
+/*
+Grammar:
+
+Tokens starting with a lower case letter are terminals; int(n)
+and uint(n) represent the signed/unsigned encodings of the value n.
+
+GobStream:
+ DelimitedMessage*
+DelimitedMessage:
+ uint(lengthOfMessage) Message
+Message:
+ TypeSequence TypedValue
+TypeSequence
+ (TypeDefinition DelimitedTypeDefinition*)?
+DelimitedTypeDefinition:
+ uint(lengthOfTypeDefinition) TypeDefinition
+TypedValue:
+ int(typeId) Value
+TypeDefinition:
+ int(-typeId) encodingOfWireType
+Value:
+ SingletonValue | StructValue
+SingletonValue:
+ uint(0) FieldValue
+FieldValue:
+ builtinValue | ArrayValue | MapValue | SliceValue | StructValue | InterfaceValue
+InterfaceValue:
+ NilInterfaceValue | NonNilInterfaceValue
+NilInterfaceValue:
+ uint(0)
+NonNilInterfaceValue:
+ ConcreteTypeName TypeSequence InterfaceContents
+ConcreteTypeName:
+ uint(lengthOfName) [already read=n] name
+InterfaceContents:
+ int(concreteTypeId) DelimitedValue
+DelimitedValue:
+ uint(length) Value
+ArrayValue:
+ uint(n) FieldValue*n [n elements]
+MapValue:
+ uint(n) (FieldValue FieldValue)*n [n (key, value) pairs]
+SliceValue:
+ uint(n) FieldValue*n [n elements]
+StructValue:
+ (uint(fieldDelta) FieldValue)*
+*/
+
+/*
+For implementers and the curious, here is an encoded example. Given
+ type Point struct {X, Y int}
+and the value
+ p := Point{22, 33}
+the bytes transmitted that encode p will be:
+ 1f ff 81 03 01 01 05 50 6f 69 6e 74 01 ff 82 00
+ 01 02 01 01 58 01 04 00 01 01 59 01 04 00 00 00
+ 07 ff 82 01 2c 01 42 00
+They are determined as follows.
+
+Since this is the first transmission of type Point, the type descriptor
+for Point itself must be sent before the value. This is the first type
+we've sent on this Encoder, so it has type id 65 (0 through 64 are
+reserved).
+
+ 1f // This item (a type descriptor) is 31 bytes long.
+ ff 81 // The negative of the id for the type we're defining, -65.
+ // This is one byte (indicated by FF = -1) followed by
+ // ^-65<<1 | 1. The low 1 bit signals to complement the
+ // rest upon receipt.
+
+ // Now we send a type descriptor, which is itself a struct (wireType).
+ // The type of wireType itself is known (it's built in, as is the type of
+ // all its components), so we just need to send a *value* of type wireType
+ // that represents type "Point".
+ // Here starts the encoding of that value.
+ // Set the field number implicitly to -1; this is done at the beginning
+ // of every struct, including nested structs.
+ 03 // Add 3 to field number; now 2 (wireType.structType; this is a struct).
+ // structType starts with an embedded CommonType, which appears
+ // as a regular structure here too.
+ 01 // add 1 to field number (now 0); start of embedded CommonType.
+ 01 // add 1 to field number (now 0, the name of the type)
+ 05 // string is (unsigned) 5 bytes long
+ 50 6f 69 6e 74 // wireType.structType.CommonType.name = "Point"
+ 01 // add 1 to field number (now 1, the id of the type)
+ ff 82 // wireType.structType.CommonType._id = 65
+ 00 // end of embedded wiretype.structType.CommonType struct
+ 01 // add 1 to field number (now 1, the field array in wireType.structType)
+ 02 // There are two fields in the type (len(structType.field))
+ 01 // Start of first field structure; add 1 to get field number 0: field[0].name
+ 01 // 1 byte
+ 58 // structType.field[0].name = "X"
+ 01 // Add 1 to get field number 1: field[0].id
+ 04 // structType.field[0].typeId is 2 (signed int).
+ 00 // End of structType.field[0]; start structType.field[1]; set field number to -1.
+ 01 // Add 1 to get field number 0: field[1].name
+ 01 // 1 byte
+ 59 // structType.field[1].name = "Y"
+ 01 // Add 1 to get field number 1: field[1].id
+ 04 // struct.Type.field[1].typeId is 2 (signed int).
+ 00 // End of structType.field[1]; end of structType.field.
+ 00 // end of wireType.structType structure
+ 00 // end of wireType structure
+
+Now we can send the Point value. Again the field number resets to -1:
+
+ 07 // this value is 7 bytes long
+ ff 82 // the type number, 65 (1 byte (-FF) followed by 65<<1)
+ 01 // add one to field number, yielding field 0
+ 2c // encoding of signed "22" (0x2c = 44 = 22<<1); Point.x = 22
+ 01 // add one to field number, yielding field 1
+ 42 // encoding of signed "33" (0x42 = 66 = 33<<1); Point.y = 33
+ 00 // end of structure
+
+The type encoding is long and fairly intricate but we send it only once.
+If p is transmitted a second time, the type is already known so the
+output will be just:
+
+ 07 ff 82 01 2c 01 42 00
+
+A single non-struct value at top level is transmitted like a field with
+delta tag 0. For instance, a signed integer with value 3 presented as
+the argument to Encode will emit:
+
+ 03 04 00 06
+
+Which represents:
+
+ 03 // this value is 3 bytes long
+ 04 // the type number, 2, represents an integer
+ 00 // tag delta 0
+ 06 // value 3
+
+*/
diff --git a/src/encoding/gob/dump.go b/src/encoding/gob/dump.go
new file mode 100644
index 0000000..8c0bbc4
--- /dev/null
+++ b/src/encoding/gob/dump.go
@@ -0,0 +1,30 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build ignore
+// +build ignore
+
+package main
+
+// Need to compile package gob with debug.go to build this program.
+// See comments in debug.go for how to do this.
+
+import (
+ "encoding/gob"
+ "fmt"
+ "os"
+)
+
+func main() {
+ var err error
+ file := os.Stdin
+ if len(os.Args) > 1 {
+ file, err = os.Open(os.Args[1])
+ if err != nil {
+ fmt.Fprintf(os.Stderr, "dump: %s\n", err)
+ os.Exit(1)
+ }
+ }
+ gob.Debug(file)
+}
diff --git a/src/encoding/gob/enc_helpers.go b/src/encoding/gob/enc_helpers.go
new file mode 100644
index 0000000..c3b4ca8
--- /dev/null
+++ b/src/encoding/gob/enc_helpers.go
@@ -0,0 +1,414 @@
+// Code generated by go run encgen.go -output enc_helpers.go; DO NOT EDIT.
+
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gob
+
+import (
+ "reflect"
+)
+
+var encArrayHelper = map[reflect.Kind]encHelper{
+ reflect.Bool: encBoolArray,
+ reflect.Complex64: encComplex64Array,
+ reflect.Complex128: encComplex128Array,
+ reflect.Float32: encFloat32Array,
+ reflect.Float64: encFloat64Array,
+ reflect.Int: encIntArray,
+ reflect.Int16: encInt16Array,
+ reflect.Int32: encInt32Array,
+ reflect.Int64: encInt64Array,
+ reflect.Int8: encInt8Array,
+ reflect.String: encStringArray,
+ reflect.Uint: encUintArray,
+ reflect.Uint16: encUint16Array,
+ reflect.Uint32: encUint32Array,
+ reflect.Uint64: encUint64Array,
+ reflect.Uintptr: encUintptrArray,
+}
+
+var encSliceHelper = map[reflect.Kind]encHelper{
+ reflect.Bool: encBoolSlice,
+ reflect.Complex64: encComplex64Slice,
+ reflect.Complex128: encComplex128Slice,
+ reflect.Float32: encFloat32Slice,
+ reflect.Float64: encFloat64Slice,
+ reflect.Int: encIntSlice,
+ reflect.Int16: encInt16Slice,
+ reflect.Int32: encInt32Slice,
+ reflect.Int64: encInt64Slice,
+ reflect.Int8: encInt8Slice,
+ reflect.String: encStringSlice,
+ reflect.Uint: encUintSlice,
+ reflect.Uint16: encUint16Slice,
+ reflect.Uint32: encUint32Slice,
+ reflect.Uint64: encUint64Slice,
+ reflect.Uintptr: encUintptrSlice,
+}
+
+func encBoolArray(state *encoderState, v reflect.Value) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return encBoolSlice(state, v.Slice(0, v.Len()))
+}
+
+func encBoolSlice(state *encoderState, v reflect.Value) bool {
+ slice, ok := v.Interface().([]bool)
+ if !ok {
+ // It is kind bool but not type bool. TODO: We can handle this unsafely.
+ return false
+ }
+ for _, x := range slice {
+ if x != false || state.sendZero {
+ if x {
+ state.encodeUint(1)
+ } else {
+ state.encodeUint(0)
+ }
+ }
+ }
+ return true
+}
+
+func encComplex64Array(state *encoderState, v reflect.Value) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return encComplex64Slice(state, v.Slice(0, v.Len()))
+}
+
+func encComplex64Slice(state *encoderState, v reflect.Value) bool {
+ slice, ok := v.Interface().([]complex64)
+ if !ok {
+ // It is kind complex64 but not type complex64. TODO: We can handle this unsafely.
+ return false
+ }
+ for _, x := range slice {
+ if x != 0+0i || state.sendZero {
+ rpart := floatBits(float64(real(x)))
+ ipart := floatBits(float64(imag(x)))
+ state.encodeUint(rpart)
+ state.encodeUint(ipart)
+ }
+ }
+ return true
+}
+
+func encComplex128Array(state *encoderState, v reflect.Value) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return encComplex128Slice(state, v.Slice(0, v.Len()))
+}
+
+func encComplex128Slice(state *encoderState, v reflect.Value) bool {
+ slice, ok := v.Interface().([]complex128)
+ if !ok {
+ // It is kind complex128 but not type complex128. TODO: We can handle this unsafely.
+ return false
+ }
+ for _, x := range slice {
+ if x != 0+0i || state.sendZero {
+ rpart := floatBits(real(x))
+ ipart := floatBits(imag(x))
+ state.encodeUint(rpart)
+ state.encodeUint(ipart)
+ }
+ }
+ return true
+}
+
+func encFloat32Array(state *encoderState, v reflect.Value) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return encFloat32Slice(state, v.Slice(0, v.Len()))
+}
+
+func encFloat32Slice(state *encoderState, v reflect.Value) bool {
+ slice, ok := v.Interface().([]float32)
+ if !ok {
+ // It is kind float32 but not type float32. TODO: We can handle this unsafely.
+ return false
+ }
+ for _, x := range slice {
+ if x != 0 || state.sendZero {
+ bits := floatBits(float64(x))
+ state.encodeUint(bits)
+ }
+ }
+ return true
+}
+
+func encFloat64Array(state *encoderState, v reflect.Value) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return encFloat64Slice(state, v.Slice(0, v.Len()))
+}
+
+func encFloat64Slice(state *encoderState, v reflect.Value) bool {
+ slice, ok := v.Interface().([]float64)
+ if !ok {
+ // It is kind float64 but not type float64. TODO: We can handle this unsafely.
+ return false
+ }
+ for _, x := range slice {
+ if x != 0 || state.sendZero {
+ bits := floatBits(x)
+ state.encodeUint(bits)
+ }
+ }
+ return true
+}
+
+func encIntArray(state *encoderState, v reflect.Value) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return encIntSlice(state, v.Slice(0, v.Len()))
+}
+
+func encIntSlice(state *encoderState, v reflect.Value) bool {
+ slice, ok := v.Interface().([]int)
+ if !ok {
+ // It is kind int but not type int. TODO: We can handle this unsafely.
+ return false
+ }
+ for _, x := range slice {
+ if x != 0 || state.sendZero {
+ state.encodeInt(int64(x))
+ }
+ }
+ return true
+}
+
+func encInt16Array(state *encoderState, v reflect.Value) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return encInt16Slice(state, v.Slice(0, v.Len()))
+}
+
+func encInt16Slice(state *encoderState, v reflect.Value) bool {
+ slice, ok := v.Interface().([]int16)
+ if !ok {
+ // It is kind int16 but not type int16. TODO: We can handle this unsafely.
+ return false
+ }
+ for _, x := range slice {
+ if x != 0 || state.sendZero {
+ state.encodeInt(int64(x))
+ }
+ }
+ return true
+}
+
+func encInt32Array(state *encoderState, v reflect.Value) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return encInt32Slice(state, v.Slice(0, v.Len()))
+}
+
+func encInt32Slice(state *encoderState, v reflect.Value) bool {
+ slice, ok := v.Interface().([]int32)
+ if !ok {
+ // It is kind int32 but not type int32. TODO: We can handle this unsafely.
+ return false
+ }
+ for _, x := range slice {
+ if x != 0 || state.sendZero {
+ state.encodeInt(int64(x))
+ }
+ }
+ return true
+}
+
+func encInt64Array(state *encoderState, v reflect.Value) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return encInt64Slice(state, v.Slice(0, v.Len()))
+}
+
+func encInt64Slice(state *encoderState, v reflect.Value) bool {
+ slice, ok := v.Interface().([]int64)
+ if !ok {
+ // It is kind int64 but not type int64. TODO: We can handle this unsafely.
+ return false
+ }
+ for _, x := range slice {
+ if x != 0 || state.sendZero {
+ state.encodeInt(x)
+ }
+ }
+ return true
+}
+
+func encInt8Array(state *encoderState, v reflect.Value) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return encInt8Slice(state, v.Slice(0, v.Len()))
+}
+
+func encInt8Slice(state *encoderState, v reflect.Value) bool {
+ slice, ok := v.Interface().([]int8)
+ if !ok {
+ // It is kind int8 but not type int8. TODO: We can handle this unsafely.
+ return false
+ }
+ for _, x := range slice {
+ if x != 0 || state.sendZero {
+ state.encodeInt(int64(x))
+ }
+ }
+ return true
+}
+
+func encStringArray(state *encoderState, v reflect.Value) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return encStringSlice(state, v.Slice(0, v.Len()))
+}
+
+func encStringSlice(state *encoderState, v reflect.Value) bool {
+ slice, ok := v.Interface().([]string)
+ if !ok {
+ // It is kind string but not type string. TODO: We can handle this unsafely.
+ return false
+ }
+ for _, x := range slice {
+ if x != "" || state.sendZero {
+ state.encodeUint(uint64(len(x)))
+ state.b.WriteString(x)
+ }
+ }
+ return true
+}
+
+func encUintArray(state *encoderState, v reflect.Value) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return encUintSlice(state, v.Slice(0, v.Len()))
+}
+
+func encUintSlice(state *encoderState, v reflect.Value) bool {
+ slice, ok := v.Interface().([]uint)
+ if !ok {
+ // It is kind uint but not type uint. TODO: We can handle this unsafely.
+ return false
+ }
+ for _, x := range slice {
+ if x != 0 || state.sendZero {
+ state.encodeUint(uint64(x))
+ }
+ }
+ return true
+}
+
+func encUint16Array(state *encoderState, v reflect.Value) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return encUint16Slice(state, v.Slice(0, v.Len()))
+}
+
+func encUint16Slice(state *encoderState, v reflect.Value) bool {
+ slice, ok := v.Interface().([]uint16)
+ if !ok {
+ // It is kind uint16 but not type uint16. TODO: We can handle this unsafely.
+ return false
+ }
+ for _, x := range slice {
+ if x != 0 || state.sendZero {
+ state.encodeUint(uint64(x))
+ }
+ }
+ return true
+}
+
+func encUint32Array(state *encoderState, v reflect.Value) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return encUint32Slice(state, v.Slice(0, v.Len()))
+}
+
+func encUint32Slice(state *encoderState, v reflect.Value) bool {
+ slice, ok := v.Interface().([]uint32)
+ if !ok {
+ // It is kind uint32 but not type uint32. TODO: We can handle this unsafely.
+ return false
+ }
+ for _, x := range slice {
+ if x != 0 || state.sendZero {
+ state.encodeUint(uint64(x))
+ }
+ }
+ return true
+}
+
+func encUint64Array(state *encoderState, v reflect.Value) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return encUint64Slice(state, v.Slice(0, v.Len()))
+}
+
+func encUint64Slice(state *encoderState, v reflect.Value) bool {
+ slice, ok := v.Interface().([]uint64)
+ if !ok {
+ // It is kind uint64 but not type uint64. TODO: We can handle this unsafely.
+ return false
+ }
+ for _, x := range slice {
+ if x != 0 || state.sendZero {
+ state.encodeUint(x)
+ }
+ }
+ return true
+}
+
+func encUintptrArray(state *encoderState, v reflect.Value) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return encUintptrSlice(state, v.Slice(0, v.Len()))
+}
+
+func encUintptrSlice(state *encoderState, v reflect.Value) bool {
+ slice, ok := v.Interface().([]uintptr)
+ if !ok {
+ // It is kind uintptr but not type uintptr. TODO: We can handle this unsafely.
+ return false
+ }
+ for _, x := range slice {
+ if x != 0 || state.sendZero {
+ state.encodeUint(uint64(x))
+ }
+ }
+ return true
+}
diff --git a/src/encoding/gob/encgen.go b/src/encoding/gob/encgen.go
new file mode 100644
index 0000000..b562da1
--- /dev/null
+++ b/src/encoding/gob/encgen.go
@@ -0,0 +1,221 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build ignore
+// +build ignore
+
+// encgen writes the helper functions for encoding. Intended to be
+// used with go generate; see the invocation in encode.go.
+
+// TODO: We could do more by being unsafe. Add a -unsafe flag?
+
+package main
+
+import (
+ "bytes"
+ "flag"
+ "fmt"
+ "go/format"
+ "log"
+ "os"
+)
+
+var output = flag.String("output", "enc_helpers.go", "file name to write")
+
+type Type struct {
+ lower string
+ upper string
+ zero string
+ encoder string
+}
+
+var types = []Type{
+ {
+ "bool",
+ "Bool",
+ "false",
+ `if x {
+ state.encodeUint(1)
+ } else {
+ state.encodeUint(0)
+ }`,
+ },
+ {
+ "complex64",
+ "Complex64",
+ "0+0i",
+ `rpart := floatBits(float64(real(x)))
+ ipart := floatBits(float64(imag(x)))
+ state.encodeUint(rpart)
+ state.encodeUint(ipart)`,
+ },
+ {
+ "complex128",
+ "Complex128",
+ "0+0i",
+ `rpart := floatBits(real(x))
+ ipart := floatBits(imag(x))
+ state.encodeUint(rpart)
+ state.encodeUint(ipart)`,
+ },
+ {
+ "float32",
+ "Float32",
+ "0",
+ `bits := floatBits(float64(x))
+ state.encodeUint(bits)`,
+ },
+ {
+ "float64",
+ "Float64",
+ "0",
+ `bits := floatBits(x)
+ state.encodeUint(bits)`,
+ },
+ {
+ "int",
+ "Int",
+ "0",
+ `state.encodeInt(int64(x))`,
+ },
+ {
+ "int16",
+ "Int16",
+ "0",
+ `state.encodeInt(int64(x))`,
+ },
+ {
+ "int32",
+ "Int32",
+ "0",
+ `state.encodeInt(int64(x))`,
+ },
+ {
+ "int64",
+ "Int64",
+ "0",
+ `state.encodeInt(x)`,
+ },
+ {
+ "int8",
+ "Int8",
+ "0",
+ `state.encodeInt(int64(x))`,
+ },
+ {
+ "string",
+ "String",
+ `""`,
+ `state.encodeUint(uint64(len(x)))
+ state.b.WriteString(x)`,
+ },
+ {
+ "uint",
+ "Uint",
+ "0",
+ `state.encodeUint(uint64(x))`,
+ },
+ {
+ "uint16",
+ "Uint16",
+ "0",
+ `state.encodeUint(uint64(x))`,
+ },
+ {
+ "uint32",
+ "Uint32",
+ "0",
+ `state.encodeUint(uint64(x))`,
+ },
+ {
+ "uint64",
+ "Uint64",
+ "0",
+ `state.encodeUint(x)`,
+ },
+ {
+ "uintptr",
+ "Uintptr",
+ "0",
+ `state.encodeUint(uint64(x))`,
+ },
+ // uint8 Handled separately.
+}
+
+func main() {
+ log.SetFlags(0)
+ log.SetPrefix("encgen: ")
+ flag.Parse()
+ if flag.NArg() != 0 {
+ log.Fatal("usage: encgen [--output filename]")
+ }
+ var b bytes.Buffer
+ fmt.Fprintf(&b, "// Code generated by go run encgen.go -output %s; DO NOT EDIT.\n", *output)
+ fmt.Fprint(&b, header)
+ printMaps(&b, "Array")
+ fmt.Fprint(&b, "\n")
+ printMaps(&b, "Slice")
+ for _, t := range types {
+ fmt.Fprintf(&b, arrayHelper, t.lower, t.upper)
+ fmt.Fprintf(&b, sliceHelper, t.lower, t.upper, t.zero, t.encoder)
+ }
+ source, err := format.Source(b.Bytes())
+ if err != nil {
+ log.Fatal("source format error:", err)
+ }
+ fd, err := os.Create(*output)
+ if err != nil {
+ log.Fatal(err)
+ }
+ if _, err := fd.Write(source); err != nil {
+ log.Fatal(err)
+ }
+}
+
+func printMaps(b *bytes.Buffer, upperClass string) {
+ fmt.Fprintf(b, "var enc%sHelper = map[reflect.Kind]encHelper{\n", upperClass)
+ for _, t := range types {
+ fmt.Fprintf(b, "reflect.%s: enc%s%s,\n", t.upper, t.upper, upperClass)
+ }
+ fmt.Fprintf(b, "}\n")
+}
+
+const header = `
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gob
+
+import (
+ "reflect"
+)
+
+`
+
+const arrayHelper = `
+func enc%[2]sArray(state *encoderState, v reflect.Value) bool {
+ // Can only slice if it is addressable.
+ if !v.CanAddr() {
+ return false
+ }
+ return enc%[2]sSlice(state, v.Slice(0, v.Len()))
+}
+`
+
+const sliceHelper = `
+func enc%[2]sSlice(state *encoderState, v reflect.Value) bool {
+ slice, ok := v.Interface().([]%[1]s)
+ if !ok {
+ // It is kind %[1]s but not type %[1]s. TODO: We can handle this unsafely.
+ return false
+ }
+ for _, x := range slice {
+ if x != %[3]s || state.sendZero {
+ %[4]s
+ }
+ }
+ return true
+}
+`
diff --git a/src/encoding/gob/encode.go b/src/encoding/gob/encode.go
new file mode 100644
index 0000000..8f8f170
--- /dev/null
+++ b/src/encoding/gob/encode.go
@@ -0,0 +1,705 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:generate go run encgen.go -output enc_helpers.go
+
+package gob
+
+import (
+ "encoding"
+ "encoding/binary"
+ "math"
+ "math/bits"
+ "reflect"
+ "sync"
+)
+
+const uint64Size = 8
+
+type encHelper func(state *encoderState, v reflect.Value) bool
+
+// encoderState is the global execution state of an instance of the encoder.
+// Field numbers are delta encoded and always increase. The field
+// number is initialized to -1 so 0 comes out as delta(1). A delta of
+// 0 terminates the structure.
+type encoderState struct {
+ enc *Encoder
+ b *encBuffer
+ sendZero bool // encoding an array element or map key/value pair; send zero values
+ fieldnum int // the last field number written.
+ buf [1 + uint64Size]byte // buffer used by the encoder; here to avoid allocation.
+ next *encoderState // for free list
+}
+
+// encBuffer is an extremely simple, fast implementation of a write-only byte buffer.
+// It never returns a non-nil error, but Write returns an error value so it matches io.Writer.
+type encBuffer struct {
+ data []byte
+ scratch [64]byte
+}
+
+var encBufferPool = sync.Pool{
+ New: func() interface{} {
+ e := new(encBuffer)
+ e.data = e.scratch[0:0]
+ return e
+ },
+}
+
+func (e *encBuffer) writeByte(c byte) {
+ e.data = append(e.data, c)
+}
+
+func (e *encBuffer) Write(p []byte) (int, error) {
+ e.data = append(e.data, p...)
+ return len(p), nil
+}
+
+func (e *encBuffer) WriteString(s string) {
+ e.data = append(e.data, s...)
+}
+
+func (e *encBuffer) Len() int {
+ return len(e.data)
+}
+
+func (e *encBuffer) Bytes() []byte {
+ return e.data
+}
+
+func (e *encBuffer) Reset() {
+ if len(e.data) >= tooBig {
+ e.data = e.scratch[0:0]
+ } else {
+ e.data = e.data[0:0]
+ }
+}
+
+func (enc *Encoder) newEncoderState(b *encBuffer) *encoderState {
+ e := enc.freeList
+ if e == nil {
+ e = new(encoderState)
+ e.enc = enc
+ } else {
+ enc.freeList = e.next
+ }
+ e.sendZero = false
+ e.fieldnum = 0
+ e.b = b
+ if len(b.data) == 0 {
+ b.data = b.scratch[0:0]
+ }
+ return e
+}
+
+func (enc *Encoder) freeEncoderState(e *encoderState) {
+ e.next = enc.freeList
+ enc.freeList = e
+}
+
+// Unsigned integers have a two-state encoding. If the number is less
+// than 128 (0 through 0x7F), its value is written directly.
+// Otherwise the value is written in big-endian byte order preceded
+// by the byte length, negated.
+
+// encodeUint writes an encoded unsigned integer to state.b.
+func (state *encoderState) encodeUint(x uint64) {
+ if x <= 0x7F {
+ state.b.writeByte(uint8(x))
+ return
+ }
+
+ binary.BigEndian.PutUint64(state.buf[1:], x)
+ bc := bits.LeadingZeros64(x) >> 3 // 8 - bytelen(x)
+ state.buf[bc] = uint8(bc - uint64Size) // and then we subtract 8 to get -bytelen(x)
+
+ state.b.Write(state.buf[bc : uint64Size+1])
+}
+
+// encodeInt writes an encoded signed integer to state.w.
+// The low bit of the encoding says whether to bit complement the (other bits of the)
+// uint to recover the int.
+func (state *encoderState) encodeInt(i int64) {
+ var x uint64
+ if i < 0 {
+ x = uint64(^i<<1) | 1
+ } else {
+ x = uint64(i << 1)
+ }
+ state.encodeUint(x)
+}
+
+// encOp is the signature of an encoding operator for a given type.
+type encOp func(i *encInstr, state *encoderState, v reflect.Value)
+
+// The 'instructions' of the encoding machine
+type encInstr struct {
+ op encOp
+ field int // field number in input
+ index []int // struct index
+ indir int // how many pointer indirections to reach the value in the struct
+}
+
+// update emits a field number and updates the state to record its value for delta encoding.
+// If the instruction pointer is nil, it does nothing
+func (state *encoderState) update(instr *encInstr) {
+ if instr != nil {
+ state.encodeUint(uint64(instr.field - state.fieldnum))
+ state.fieldnum = instr.field
+ }
+}
+
+// Each encoder for a composite is responsible for handling any
+// indirections associated with the elements of the data structure.
+// If any pointer so reached is nil, no bytes are written. If the
+// data item is zero, no bytes are written. Single values - ints,
+// strings etc. - are indirected before calling their encoders.
+// Otherwise, the output (for a scalar) is the field number, as an
+// encoded integer, followed by the field data in its appropriate
+// format.
+
+// encIndirect dereferences pv indir times and returns the result.
+func encIndirect(pv reflect.Value, indir int) reflect.Value {
+ for ; indir > 0; indir-- {
+ if pv.IsNil() {
+ break
+ }
+ pv = pv.Elem()
+ }
+ return pv
+}
+
+// encBool encodes the bool referenced by v as an unsigned 0 or 1.
+func encBool(i *encInstr, state *encoderState, v reflect.Value) {
+ b := v.Bool()
+ if b || state.sendZero {
+ state.update(i)
+ if b {
+ state.encodeUint(1)
+ } else {
+ state.encodeUint(0)
+ }
+ }
+}
+
+// encInt encodes the signed integer (int int8 int16 int32 int64) referenced by v.
+func encInt(i *encInstr, state *encoderState, v reflect.Value) {
+ value := v.Int()
+ if value != 0 || state.sendZero {
+ state.update(i)
+ state.encodeInt(value)
+ }
+}
+
+// encUint encodes the unsigned integer (uint uint8 uint16 uint32 uint64 uintptr) referenced by v.
+func encUint(i *encInstr, state *encoderState, v reflect.Value) {
+ value := v.Uint()
+ if value != 0 || state.sendZero {
+ state.update(i)
+ state.encodeUint(value)
+ }
+}
+
+// floatBits returns a uint64 holding the bits of a floating-point number.
+// Floating-point numbers are transmitted as uint64s holding the bits
+// of the underlying representation. They are sent byte-reversed, with
+// the exponent end coming out first, so integer floating point numbers
+// (for example) transmit more compactly. This routine does the
+// swizzling.
+func floatBits(f float64) uint64 {
+ u := math.Float64bits(f)
+ return bits.ReverseBytes64(u)
+}
+
+// encFloat encodes the floating point value (float32 float64) referenced by v.
+func encFloat(i *encInstr, state *encoderState, v reflect.Value) {
+ f := v.Float()
+ if f != 0 || state.sendZero {
+ bits := floatBits(f)
+ state.update(i)
+ state.encodeUint(bits)
+ }
+}
+
+// encComplex encodes the complex value (complex64 complex128) referenced by v.
+// Complex numbers are just a pair of floating-point numbers, real part first.
+func encComplex(i *encInstr, state *encoderState, v reflect.Value) {
+ c := v.Complex()
+ if c != 0+0i || state.sendZero {
+ rpart := floatBits(real(c))
+ ipart := floatBits(imag(c))
+ state.update(i)
+ state.encodeUint(rpart)
+ state.encodeUint(ipart)
+ }
+}
+
+// encUint8Array encodes the byte array referenced by v.
+// Byte arrays are encoded as an unsigned count followed by the raw bytes.
+func encUint8Array(i *encInstr, state *encoderState, v reflect.Value) {
+ b := v.Bytes()
+ if len(b) > 0 || state.sendZero {
+ state.update(i)
+ state.encodeUint(uint64(len(b)))
+ state.b.Write(b)
+ }
+}
+
+// encString encodes the string referenced by v.
+// Strings are encoded as an unsigned count followed by the raw bytes.
+func encString(i *encInstr, state *encoderState, v reflect.Value) {
+ s := v.String()
+ if len(s) > 0 || state.sendZero {
+ state.update(i)
+ state.encodeUint(uint64(len(s)))
+ state.b.WriteString(s)
+ }
+}
+
+// encStructTerminator encodes the end of an encoded struct
+// as delta field number of 0.
+func encStructTerminator(i *encInstr, state *encoderState, v reflect.Value) {
+ state.encodeUint(0)
+}
+
+// Execution engine
+
+// encEngine an array of instructions indexed by field number of the encoding
+// data, typically a struct. It is executed top to bottom, walking the struct.
+type encEngine struct {
+ instr []encInstr
+}
+
+const singletonField = 0
+
+// valid reports whether the value is valid and a non-nil pointer.
+// (Slices, maps, and chans take care of themselves.)
+func valid(v reflect.Value) bool {
+ switch v.Kind() {
+ case reflect.Invalid:
+ return false
+ case reflect.Ptr:
+ return !v.IsNil()
+ }
+ return true
+}
+
+// encodeSingle encodes a single top-level non-struct value.
+func (enc *Encoder) encodeSingle(b *encBuffer, engine *encEngine, value reflect.Value) {
+ state := enc.newEncoderState(b)
+ defer enc.freeEncoderState(state)
+ state.fieldnum = singletonField
+ // There is no surrounding struct to frame the transmission, so we must
+ // generate data even if the item is zero. To do this, set sendZero.
+ state.sendZero = true
+ instr := &engine.instr[singletonField]
+ if instr.indir > 0 {
+ value = encIndirect(value, instr.indir)
+ }
+ if valid(value) {
+ instr.op(instr, state, value)
+ }
+}
+
+// encodeStruct encodes a single struct value.
+func (enc *Encoder) encodeStruct(b *encBuffer, engine *encEngine, value reflect.Value) {
+ if !valid(value) {
+ return
+ }
+ state := enc.newEncoderState(b)
+ defer enc.freeEncoderState(state)
+ state.fieldnum = -1
+ for i := 0; i < len(engine.instr); i++ {
+ instr := &engine.instr[i]
+ if i >= value.NumField() {
+ // encStructTerminator
+ instr.op(instr, state, reflect.Value{})
+ break
+ }
+ field := value.FieldByIndex(instr.index)
+ if instr.indir > 0 {
+ field = encIndirect(field, instr.indir)
+ // TODO: Is field guaranteed valid? If so we could avoid this check.
+ if !valid(field) {
+ continue
+ }
+ }
+ instr.op(instr, state, field)
+ }
+}
+
+// encodeArray encodes an array.
+func (enc *Encoder) encodeArray(b *encBuffer, value reflect.Value, op encOp, elemIndir int, length int, helper encHelper) {
+ state := enc.newEncoderState(b)
+ defer enc.freeEncoderState(state)
+ state.fieldnum = -1
+ state.sendZero = true
+ state.encodeUint(uint64(length))
+ if helper != nil && helper(state, value) {
+ return
+ }
+ for i := 0; i < length; i++ {
+ elem := value.Index(i)
+ if elemIndir > 0 {
+ elem = encIndirect(elem, elemIndir)
+ // TODO: Is elem guaranteed valid? If so we could avoid this check.
+ if !valid(elem) {
+ errorf("encodeArray: nil element")
+ }
+ }
+ op(nil, state, elem)
+ }
+}
+
+// encodeReflectValue is a helper for maps. It encodes the value v.
+func encodeReflectValue(state *encoderState, v reflect.Value, op encOp, indir int) {
+ for i := 0; i < indir && v.IsValid(); i++ {
+ v = reflect.Indirect(v)
+ }
+ if !v.IsValid() {
+ errorf("encodeReflectValue: nil element")
+ }
+ op(nil, state, v)
+}
+
+// encodeMap encodes a map as unsigned count followed by key:value pairs.
+func (enc *Encoder) encodeMap(b *encBuffer, mv reflect.Value, keyOp, elemOp encOp, keyIndir, elemIndir int) {
+ state := enc.newEncoderState(b)
+ state.fieldnum = -1
+ state.sendZero = true
+ keys := mv.MapKeys()
+ state.encodeUint(uint64(len(keys)))
+ for _, key := range keys {
+ encodeReflectValue(state, key, keyOp, keyIndir)
+ encodeReflectValue(state, mv.MapIndex(key), elemOp, elemIndir)
+ }
+ enc.freeEncoderState(state)
+}
+
+// encodeInterface encodes the interface value iv.
+// To send an interface, we send a string identifying the concrete type, followed
+// by the type identifier (which might require defining that type right now), followed
+// by the concrete value. A nil value gets sent as the empty string for the name,
+// followed by no value.
+func (enc *Encoder) encodeInterface(b *encBuffer, iv reflect.Value) {
+ // Gobs can encode nil interface values but not typed interface
+ // values holding nil pointers, since nil pointers point to no value.
+ elem := iv.Elem()
+ if elem.Kind() == reflect.Ptr && elem.IsNil() {
+ errorf("gob: cannot encode nil pointer of type %s inside interface", iv.Elem().Type())
+ }
+ state := enc.newEncoderState(b)
+ state.fieldnum = -1
+ state.sendZero = true
+ if iv.IsNil() {
+ state.encodeUint(0)
+ return
+ }
+
+ ut := userType(iv.Elem().Type())
+ namei, ok := concreteTypeToName.Load(ut.base)
+ if !ok {
+ errorf("type not registered for interface: %s", ut.base)
+ }
+ name := namei.(string)
+
+ // Send the name.
+ state.encodeUint(uint64(len(name)))
+ state.b.WriteString(name)
+ // Define the type id if necessary.
+ enc.sendTypeDescriptor(enc.writer(), state, ut)
+ // Send the type id.
+ enc.sendTypeId(state, ut)
+ // Encode the value into a new buffer. Any nested type definitions
+ // should be written to b, before the encoded value.
+ enc.pushWriter(b)
+ data := encBufferPool.Get().(*encBuffer)
+ data.Write(spaceForLength)
+ enc.encode(data, elem, ut)
+ if enc.err != nil {
+ error_(enc.err)
+ }
+ enc.popWriter()
+ enc.writeMessage(b, data)
+ data.Reset()
+ encBufferPool.Put(data)
+ if enc.err != nil {
+ error_(enc.err)
+ }
+ enc.freeEncoderState(state)
+}
+
+// isZero reports whether the value is the zero of its type.
+func isZero(val reflect.Value) bool {
+ switch val.Kind() {
+ case reflect.Array:
+ for i := 0; i < val.Len(); i++ {
+ if !isZero(val.Index(i)) {
+ return false
+ }
+ }
+ return true
+ case reflect.Map, reflect.Slice, reflect.String:
+ return val.Len() == 0
+ case reflect.Bool:
+ return !val.Bool()
+ case reflect.Complex64, reflect.Complex128:
+ return val.Complex() == 0
+ case reflect.Chan, reflect.Func, reflect.Interface, reflect.Ptr:
+ return val.IsNil()
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ return val.Int() == 0
+ case reflect.Float32, reflect.Float64:
+ return val.Float() == 0
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ return val.Uint() == 0
+ case reflect.Struct:
+ for i := 0; i < val.NumField(); i++ {
+ if !isZero(val.Field(i)) {
+ return false
+ }
+ }
+ return true
+ }
+ panic("unknown type in isZero " + val.Type().String())
+}
+
+// encGobEncoder encodes a value that implements the GobEncoder interface.
+// The data is sent as a byte array.
+func (enc *Encoder) encodeGobEncoder(b *encBuffer, ut *userTypeInfo, v reflect.Value) {
+ // TODO: should we catch panics from the called method?
+
+ var data []byte
+ var err error
+ // We know it's one of these.
+ switch ut.externalEnc {
+ case xGob:
+ data, err = v.Interface().(GobEncoder).GobEncode()
+ case xBinary:
+ data, err = v.Interface().(encoding.BinaryMarshaler).MarshalBinary()
+ case xText:
+ data, err = v.Interface().(encoding.TextMarshaler).MarshalText()
+ }
+ if err != nil {
+ error_(err)
+ }
+ state := enc.newEncoderState(b)
+ state.fieldnum = -1
+ state.encodeUint(uint64(len(data)))
+ state.b.Write(data)
+ enc.freeEncoderState(state)
+}
+
+var encOpTable = [...]encOp{
+ reflect.Bool: encBool,
+ reflect.Int: encInt,
+ reflect.Int8: encInt,
+ reflect.Int16: encInt,
+ reflect.Int32: encInt,
+ reflect.Int64: encInt,
+ reflect.Uint: encUint,
+ reflect.Uint8: encUint,
+ reflect.Uint16: encUint,
+ reflect.Uint32: encUint,
+ reflect.Uint64: encUint,
+ reflect.Uintptr: encUint,
+ reflect.Float32: encFloat,
+ reflect.Float64: encFloat,
+ reflect.Complex64: encComplex,
+ reflect.Complex128: encComplex,
+ reflect.String: encString,
+}
+
+// encOpFor returns (a pointer to) the encoding op for the base type under rt and
+// the indirection count to reach it.
+func encOpFor(rt reflect.Type, inProgress map[reflect.Type]*encOp, building map[*typeInfo]bool) (*encOp, int) {
+ ut := userType(rt)
+ // If the type implements GobEncoder, we handle it without further processing.
+ if ut.externalEnc != 0 {
+ return gobEncodeOpFor(ut)
+ }
+ // If this type is already in progress, it's a recursive type (e.g. map[string]*T).
+ // Return the pointer to the op we're already building.
+ if opPtr := inProgress[rt]; opPtr != nil {
+ return opPtr, ut.indir
+ }
+ typ := ut.base
+ indir := ut.indir
+ k := typ.Kind()
+ var op encOp
+ if int(k) < len(encOpTable) {
+ op = encOpTable[k]
+ }
+ if op == nil {
+ inProgress[rt] = &op
+ // Special cases
+ switch t := typ; t.Kind() {
+ case reflect.Slice:
+ if t.Elem().Kind() == reflect.Uint8 {
+ op = encUint8Array
+ break
+ }
+ // Slices have a header; we decode it to find the underlying array.
+ elemOp, elemIndir := encOpFor(t.Elem(), inProgress, building)
+ helper := encSliceHelper[t.Elem().Kind()]
+ op = func(i *encInstr, state *encoderState, slice reflect.Value) {
+ if !state.sendZero && slice.Len() == 0 {
+ return
+ }
+ state.update(i)
+ state.enc.encodeArray(state.b, slice, *elemOp, elemIndir, slice.Len(), helper)
+ }
+ case reflect.Array:
+ // True arrays have size in the type.
+ elemOp, elemIndir := encOpFor(t.Elem(), inProgress, building)
+ helper := encArrayHelper[t.Elem().Kind()]
+ op = func(i *encInstr, state *encoderState, array reflect.Value) {
+ state.update(i)
+ state.enc.encodeArray(state.b, array, *elemOp, elemIndir, array.Len(), helper)
+ }
+ case reflect.Map:
+ keyOp, keyIndir := encOpFor(t.Key(), inProgress, building)
+ elemOp, elemIndir := encOpFor(t.Elem(), inProgress, building)
+ op = func(i *encInstr, state *encoderState, mv reflect.Value) {
+ // We send zero-length (but non-nil) maps because the
+ // receiver might want to use the map. (Maps don't use append.)
+ if !state.sendZero && mv.IsNil() {
+ return
+ }
+ state.update(i)
+ state.enc.encodeMap(state.b, mv, *keyOp, *elemOp, keyIndir, elemIndir)
+ }
+ case reflect.Struct:
+ // Generate a closure that calls out to the engine for the nested type.
+ getEncEngine(userType(typ), building)
+ info := mustGetTypeInfo(typ)
+ op = func(i *encInstr, state *encoderState, sv reflect.Value) {
+ state.update(i)
+ // indirect through info to delay evaluation for recursive structs
+ enc := info.encoder.Load().(*encEngine)
+ state.enc.encodeStruct(state.b, enc, sv)
+ }
+ case reflect.Interface:
+ op = func(i *encInstr, state *encoderState, iv reflect.Value) {
+ if !state.sendZero && (!iv.IsValid() || iv.IsNil()) {
+ return
+ }
+ state.update(i)
+ state.enc.encodeInterface(state.b, iv)
+ }
+ }
+ }
+ if op == nil {
+ errorf("can't happen: encode type %s", rt)
+ }
+ return &op, indir
+}
+
+// gobEncodeOpFor returns the op for a type that is known to implement GobEncoder.
+func gobEncodeOpFor(ut *userTypeInfo) (*encOp, int) {
+ rt := ut.user
+ if ut.encIndir == -1 {
+ rt = reflect.PtrTo(rt)
+ } else if ut.encIndir > 0 {
+ for i := int8(0); i < ut.encIndir; i++ {
+ rt = rt.Elem()
+ }
+ }
+ var op encOp
+ op = func(i *encInstr, state *encoderState, v reflect.Value) {
+ if ut.encIndir == -1 {
+ // Need to climb up one level to turn value into pointer.
+ if !v.CanAddr() {
+ errorf("unaddressable value of type %s", rt)
+ }
+ v = v.Addr()
+ }
+ if !state.sendZero && isZero(v) {
+ return
+ }
+ state.update(i)
+ state.enc.encodeGobEncoder(state.b, ut, v)
+ }
+ return &op, int(ut.encIndir) // encIndir: op will get called with p == address of receiver.
+}
+
+// compileEnc returns the engine to compile the type.
+func compileEnc(ut *userTypeInfo, building map[*typeInfo]bool) *encEngine {
+ srt := ut.base
+ engine := new(encEngine)
+ seen := make(map[reflect.Type]*encOp)
+ rt := ut.base
+ if ut.externalEnc != 0 {
+ rt = ut.user
+ }
+ if ut.externalEnc == 0 && srt.Kind() == reflect.Struct {
+ for fieldNum, wireFieldNum := 0, 0; fieldNum < srt.NumField(); fieldNum++ {
+ f := srt.Field(fieldNum)
+ if !isSent(&f) {
+ continue
+ }
+ op, indir := encOpFor(f.Type, seen, building)
+ engine.instr = append(engine.instr, encInstr{*op, wireFieldNum, f.Index, indir})
+ wireFieldNum++
+ }
+ if srt.NumField() > 0 && len(engine.instr) == 0 {
+ errorf("type %s has no exported fields", rt)
+ }
+ engine.instr = append(engine.instr, encInstr{encStructTerminator, 0, nil, 0})
+ } else {
+ engine.instr = make([]encInstr, 1)
+ op, indir := encOpFor(rt, seen, building)
+ engine.instr[0] = encInstr{*op, singletonField, nil, indir}
+ }
+ return engine
+}
+
+// getEncEngine returns the engine to compile the type.
+func getEncEngine(ut *userTypeInfo, building map[*typeInfo]bool) *encEngine {
+ info, err := getTypeInfo(ut)
+ if err != nil {
+ error_(err)
+ }
+ enc, ok := info.encoder.Load().(*encEngine)
+ if !ok {
+ enc = buildEncEngine(info, ut, building)
+ }
+ return enc
+}
+
+func buildEncEngine(info *typeInfo, ut *userTypeInfo, building map[*typeInfo]bool) *encEngine {
+ // Check for recursive types.
+ if building != nil && building[info] {
+ return nil
+ }
+ info.encInit.Lock()
+ defer info.encInit.Unlock()
+ enc, ok := info.encoder.Load().(*encEngine)
+ if !ok {
+ if building == nil {
+ building = make(map[*typeInfo]bool)
+ }
+ building[info] = true
+ enc = compileEnc(ut, building)
+ info.encoder.Store(enc)
+ }
+ return enc
+}
+
+func (enc *Encoder) encode(b *encBuffer, value reflect.Value, ut *userTypeInfo) {
+ defer catchError(&enc.err)
+ engine := getEncEngine(ut, nil)
+ indir := ut.indir
+ if ut.externalEnc != 0 {
+ indir = int(ut.encIndir)
+ }
+ for i := 0; i < indir; i++ {
+ value = reflect.Indirect(value)
+ }
+ if ut.externalEnc == 0 && value.Type().Kind() == reflect.Struct {
+ enc.encodeStruct(b, engine, value)
+ } else {
+ enc.encodeSingle(b, engine, value)
+ }
+}
diff --git a/src/encoding/gob/encoder.go b/src/encoding/gob/encoder.go
new file mode 100644
index 0000000..53e2cac
--- /dev/null
+++ b/src/encoding/gob/encoder.go
@@ -0,0 +1,258 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gob
+
+import (
+ "errors"
+ "io"
+ "reflect"
+ "sync"
+)
+
+// An Encoder manages the transmission of type and data information to the
+// other side of a connection. It is safe for concurrent use by multiple
+// goroutines.
+type Encoder struct {
+ mutex sync.Mutex // each item must be sent atomically
+ w []io.Writer // where to send the data
+ sent map[reflect.Type]typeId // which types we've already sent
+ countState *encoderState // stage for writing counts
+ freeList *encoderState // list of free encoderStates; avoids reallocation
+ byteBuf encBuffer // buffer for top-level encoderState
+ err error
+}
+
+// Before we encode a message, we reserve space at the head of the
+// buffer in which to encode its length. This means we can use the
+// buffer to assemble the message without another allocation.
+const maxLength = 9 // Maximum size of an encoded length.
+var spaceForLength = make([]byte, maxLength)
+
+// NewEncoder returns a new encoder that will transmit on the io.Writer.
+func NewEncoder(w io.Writer) *Encoder {
+ enc := new(Encoder)
+ enc.w = []io.Writer{w}
+ enc.sent = make(map[reflect.Type]typeId)
+ enc.countState = enc.newEncoderState(new(encBuffer))
+ return enc
+}
+
+// writer() returns the innermost writer the encoder is using
+func (enc *Encoder) writer() io.Writer {
+ return enc.w[len(enc.w)-1]
+}
+
+// pushWriter adds a writer to the encoder.
+func (enc *Encoder) pushWriter(w io.Writer) {
+ enc.w = append(enc.w, w)
+}
+
+// popWriter pops the innermost writer.
+func (enc *Encoder) popWriter() {
+ enc.w = enc.w[0 : len(enc.w)-1]
+}
+
+func (enc *Encoder) setError(err error) {
+ if enc.err == nil { // remember the first.
+ enc.err = err
+ }
+}
+
+// writeMessage sends the data item preceded by a unsigned count of its length.
+func (enc *Encoder) writeMessage(w io.Writer, b *encBuffer) {
+ // Space has been reserved for the length at the head of the message.
+ // This is a little dirty: we grab the slice from the bytes.Buffer and massage
+ // it by hand.
+ message := b.Bytes()
+ messageLen := len(message) - maxLength
+ // Length cannot be bigger than the decoder can handle.
+ if messageLen >= tooBig {
+ enc.setError(errors.New("gob: encoder: message too big"))
+ return
+ }
+ // Encode the length.
+ enc.countState.b.Reset()
+ enc.countState.encodeUint(uint64(messageLen))
+ // Copy the length to be a prefix of the message.
+ offset := maxLength - enc.countState.b.Len()
+ copy(message[offset:], enc.countState.b.Bytes())
+ // Write the data.
+ _, err := w.Write(message[offset:])
+ // Drain the buffer and restore the space at the front for the count of the next message.
+ b.Reset()
+ b.Write(spaceForLength)
+ if err != nil {
+ enc.setError(err)
+ }
+}
+
+// sendActualType sends the requested type, without further investigation, unless
+// it's been sent before.
+func (enc *Encoder) sendActualType(w io.Writer, state *encoderState, ut *userTypeInfo, actual reflect.Type) (sent bool) {
+ if _, alreadySent := enc.sent[actual]; alreadySent {
+ return false
+ }
+ info, err := getTypeInfo(ut)
+ if err != nil {
+ enc.setError(err)
+ return
+ }
+ // Send the pair (-id, type)
+ // Id:
+ state.encodeInt(-int64(info.id))
+ // Type:
+ enc.encode(state.b, reflect.ValueOf(info.wire), wireTypeUserInfo)
+ enc.writeMessage(w, state.b)
+ if enc.err != nil {
+ return
+ }
+
+ // Remember we've sent this type, both what the user gave us and the base type.
+ enc.sent[ut.base] = info.id
+ if ut.user != ut.base {
+ enc.sent[ut.user] = info.id
+ }
+ // Now send the inner types
+ switch st := actual; st.Kind() {
+ case reflect.Struct:
+ for i := 0; i < st.NumField(); i++ {
+ if isExported(st.Field(i).Name) {
+ enc.sendType(w, state, st.Field(i).Type)
+ }
+ }
+ case reflect.Array, reflect.Slice:
+ enc.sendType(w, state, st.Elem())
+ case reflect.Map:
+ enc.sendType(w, state, st.Key())
+ enc.sendType(w, state, st.Elem())
+ }
+ return true
+}
+
+// sendType sends the type info to the other side, if necessary.
+func (enc *Encoder) sendType(w io.Writer, state *encoderState, origt reflect.Type) (sent bool) {
+ ut := userType(origt)
+ if ut.externalEnc != 0 {
+ // The rules are different: regardless of the underlying type's representation,
+ // we need to tell the other side that the base type is a GobEncoder.
+ return enc.sendActualType(w, state, ut, ut.base)
+ }
+
+ // It's a concrete value, so drill down to the base type.
+ switch rt := ut.base; rt.Kind() {
+ default:
+ // Basic types and interfaces do not need to be described.
+ return
+ case reflect.Slice:
+ // If it's []uint8, don't send; it's considered basic.
+ if rt.Elem().Kind() == reflect.Uint8 {
+ return
+ }
+ // Otherwise we do send.
+ break
+ case reflect.Array:
+ // arrays must be sent so we know their lengths and element types.
+ break
+ case reflect.Map:
+ // maps must be sent so we know their lengths and key/value types.
+ break
+ case reflect.Struct:
+ // structs must be sent so we know their fields.
+ break
+ case reflect.Chan, reflect.Func:
+ // If we get here, it's a field of a struct; ignore it.
+ return
+ }
+
+ return enc.sendActualType(w, state, ut, ut.base)
+}
+
+// Encode transmits the data item represented by the empty interface value,
+// guaranteeing that all necessary type information has been transmitted first.
+// Passing a nil pointer to Encoder will panic, as they cannot be transmitted by gob.
+func (enc *Encoder) Encode(e interface{}) error {
+ return enc.EncodeValue(reflect.ValueOf(e))
+}
+
+// sendTypeDescriptor makes sure the remote side knows about this type.
+// It will send a descriptor if this is the first time the type has been
+// sent.
+func (enc *Encoder) sendTypeDescriptor(w io.Writer, state *encoderState, ut *userTypeInfo) {
+ // Make sure the type is known to the other side.
+ // First, have we already sent this type?
+ rt := ut.base
+ if ut.externalEnc != 0 {
+ rt = ut.user
+ }
+ if _, alreadySent := enc.sent[rt]; !alreadySent {
+ // No, so send it.
+ sent := enc.sendType(w, state, rt)
+ if enc.err != nil {
+ return
+ }
+ // If the type info has still not been transmitted, it means we have
+ // a singleton basic type (int, []byte etc.) at top level. We don't
+ // need to send the type info but we do need to update enc.sent.
+ if !sent {
+ info, err := getTypeInfo(ut)
+ if err != nil {
+ enc.setError(err)
+ return
+ }
+ enc.sent[rt] = info.id
+ }
+ }
+}
+
+// sendTypeId sends the id, which must have already been defined.
+func (enc *Encoder) sendTypeId(state *encoderState, ut *userTypeInfo) {
+ // Identify the type of this top-level value.
+ state.encodeInt(int64(enc.sent[ut.base]))
+}
+
+// EncodeValue transmits the data item represented by the reflection value,
+// guaranteeing that all necessary type information has been transmitted first.
+// Passing a nil pointer to EncodeValue will panic, as they cannot be transmitted by gob.
+func (enc *Encoder) EncodeValue(value reflect.Value) error {
+ if value.Kind() == reflect.Invalid {
+ return errors.New("gob: cannot encode nil value")
+ }
+ if value.Kind() == reflect.Ptr && value.IsNil() {
+ panic("gob: cannot encode nil pointer of type " + value.Type().String())
+ }
+
+ // Make sure we're single-threaded through here, so multiple
+ // goroutines can share an encoder.
+ enc.mutex.Lock()
+ defer enc.mutex.Unlock()
+
+ // Remove any nested writers remaining due to previous errors.
+ enc.w = enc.w[0:1]
+
+ ut, err := validUserType(value.Type())
+ if err != nil {
+ return err
+ }
+
+ enc.err = nil
+ enc.byteBuf.Reset()
+ enc.byteBuf.Write(spaceForLength)
+ state := enc.newEncoderState(&enc.byteBuf)
+
+ enc.sendTypeDescriptor(enc.writer(), state, ut)
+ enc.sendTypeId(state, ut)
+ if enc.err != nil {
+ return enc.err
+ }
+
+ // Encode the object.
+ enc.encode(state.b, value, ut)
+ if enc.err == nil {
+ enc.writeMessage(enc.writer(), state.b)
+ }
+
+ enc.freeEncoderState(state)
+ return enc.err
+}
diff --git a/src/encoding/gob/encoder_test.go b/src/encoding/gob/encoder_test.go
new file mode 100644
index 0000000..6183646
--- /dev/null
+++ b/src/encoding/gob/encoder_test.go
@@ -0,0 +1,1154 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gob
+
+import (
+ "bytes"
+ "encoding/hex"
+ "fmt"
+ "io"
+ "reflect"
+ "strings"
+ "testing"
+)
+
+// Test basic operations in a safe manner.
+func TestBasicEncoderDecoder(t *testing.T) {
+ var values = []interface{}{
+ true,
+ int(123),
+ int8(123),
+ int16(-12345),
+ int32(123456),
+ int64(-1234567),
+ uint(123),
+ uint8(123),
+ uint16(12345),
+ uint32(123456),
+ uint64(1234567),
+ uintptr(12345678),
+ float32(1.2345),
+ float64(1.2345678),
+ complex64(1.2345 + 2.3456i),
+ complex128(1.2345678 + 2.3456789i),
+ []byte("hello"),
+ string("hello"),
+ }
+ for _, value := range values {
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ err := enc.Encode(value)
+ if err != nil {
+ t.Error("encoder fail:", err)
+ }
+ dec := NewDecoder(b)
+ result := reflect.New(reflect.TypeOf(value))
+ err = dec.Decode(result.Interface())
+ if err != nil {
+ t.Fatalf("error decoding %T: %v:", reflect.TypeOf(value), err)
+ }
+ if !reflect.DeepEqual(value, result.Elem().Interface()) {
+ t.Fatalf("%T: expected %v got %v", value, value, result.Elem().Interface())
+ }
+ }
+}
+
+func TestEncodeIntSlice(t *testing.T) {
+
+ s8 := []int8{1, 5, 12, 22, 35, 51, 70, 92, 117}
+ s16 := []int16{145, 176, 210, 247, 287, 330, 376, 425, 477}
+ s32 := []int32{532, 590, 651, 715, 782, 852, 925, 1001, 1080}
+ s64 := []int64{1162, 1247, 1335, 1426, 1520, 1617, 1717, 1820, 1926}
+
+ t.Run("int8", func(t *testing.T) {
+ var sink bytes.Buffer
+ enc := NewEncoder(&sink)
+ enc.Encode(s8)
+
+ dec := NewDecoder(&sink)
+ res := make([]int8, 9)
+ dec.Decode(&res)
+
+ if !reflect.DeepEqual(s8, res) {
+ t.Fatalf("EncodeIntSlice: expected %v, got %v", s8, res)
+ }
+ })
+
+ t.Run("int16", func(t *testing.T) {
+ var sink bytes.Buffer
+ enc := NewEncoder(&sink)
+ enc.Encode(s16)
+
+ dec := NewDecoder(&sink)
+ res := make([]int16, 9)
+ dec.Decode(&res)
+
+ if !reflect.DeepEqual(s16, res) {
+ t.Fatalf("EncodeIntSlice: expected %v, got %v", s16, res)
+ }
+ })
+
+ t.Run("int32", func(t *testing.T) {
+ var sink bytes.Buffer
+ enc := NewEncoder(&sink)
+ enc.Encode(s32)
+
+ dec := NewDecoder(&sink)
+ res := make([]int32, 9)
+ dec.Decode(&res)
+
+ if !reflect.DeepEqual(s32, res) {
+ t.Fatalf("EncodeIntSlice: expected %v, got %v", s32, res)
+ }
+ })
+
+ t.Run("int64", func(t *testing.T) {
+ var sink bytes.Buffer
+ enc := NewEncoder(&sink)
+ enc.Encode(s64)
+
+ dec := NewDecoder(&sink)
+ res := make([]int64, 9)
+ dec.Decode(&res)
+
+ if !reflect.DeepEqual(s64, res) {
+ t.Fatalf("EncodeIntSlice: expected %v, got %v", s64, res)
+ }
+ })
+
+}
+
+type ET0 struct {
+ A int
+ B string
+}
+
+type ET2 struct {
+ X string
+}
+
+type ET1 struct {
+ A int
+ Et2 *ET2
+ Next *ET1
+}
+
+// Like ET1 but with a different name for a field
+type ET3 struct {
+ A int
+ Et2 *ET2
+ DifferentNext *ET1
+}
+
+// Like ET1 but with a different type for a field
+type ET4 struct {
+ A int
+ Et2 float64
+ Next int
+}
+
+func TestEncoderDecoder(t *testing.T) {
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ et0 := new(ET0)
+ et0.A = 7
+ et0.B = "gobs of fun"
+ err := enc.Encode(et0)
+ if err != nil {
+ t.Error("encoder fail:", err)
+ }
+ //fmt.Printf("% x %q\n", b, b)
+ //Debug(b)
+ dec := NewDecoder(b)
+ newEt0 := new(ET0)
+ err = dec.Decode(newEt0)
+ if err != nil {
+ t.Fatal("error decoding ET0:", err)
+ }
+
+ if !reflect.DeepEqual(et0, newEt0) {
+ t.Fatalf("invalid data for et0: expected %+v; got %+v", *et0, *newEt0)
+ }
+ if b.Len() != 0 {
+ t.Error("not at eof;", b.Len(), "bytes left")
+ }
+ // t.FailNow()
+
+ b = new(bytes.Buffer)
+ enc = NewEncoder(b)
+ et1 := new(ET1)
+ et1.A = 7
+ et1.Et2 = new(ET2)
+ err = enc.Encode(et1)
+ if err != nil {
+ t.Error("encoder fail:", err)
+ }
+ dec = NewDecoder(b)
+ newEt1 := new(ET1)
+ err = dec.Decode(newEt1)
+ if err != nil {
+ t.Fatal("error decoding ET1:", err)
+ }
+
+ if !reflect.DeepEqual(et1, newEt1) {
+ t.Fatalf("invalid data for et1: expected %+v; got %+v", *et1, *newEt1)
+ }
+ if b.Len() != 0 {
+ t.Error("not at eof;", b.Len(), "bytes left")
+ }
+
+ enc.Encode(et1)
+ newEt1 = new(ET1)
+ err = dec.Decode(newEt1)
+ if err != nil {
+ t.Fatal("round 2: error decoding ET1:", err)
+ }
+ if !reflect.DeepEqual(et1, newEt1) {
+ t.Fatalf("round 2: invalid data for et1: expected %+v; got %+v", *et1, *newEt1)
+ }
+ if b.Len() != 0 {
+ t.Error("round 2: not at eof;", b.Len(), "bytes left")
+ }
+
+ // Now test with a running encoder/decoder pair that we recognize a type mismatch.
+ err = enc.Encode(et1)
+ if err != nil {
+ t.Error("round 3: encoder fail:", err)
+ }
+ newEt2 := new(ET2)
+ err = dec.Decode(newEt2)
+ if err == nil {
+ t.Fatal("round 3: expected `bad type' error decoding ET2")
+ }
+}
+
+// Run one value through the encoder/decoder, but use the wrong type.
+// Input is always an ET1; we compare it to whatever is under 'e'.
+func badTypeCheck(e interface{}, shouldFail bool, msg string, t *testing.T) {
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ et1 := new(ET1)
+ et1.A = 7
+ et1.Et2 = new(ET2)
+ err := enc.Encode(et1)
+ if err != nil {
+ t.Error("encoder fail:", err)
+ }
+ dec := NewDecoder(b)
+ err = dec.Decode(e)
+ if shouldFail && err == nil {
+ t.Error("expected error for", msg)
+ }
+ if !shouldFail && err != nil {
+ t.Error("unexpected error for", msg, err)
+ }
+}
+
+// Test that we recognize a bad type the first time.
+func TestWrongTypeDecoder(t *testing.T) {
+ badTypeCheck(new(ET2), true, "no fields in common", t)
+ badTypeCheck(new(ET3), false, "different name of field", t)
+ badTypeCheck(new(ET4), true, "different type of field", t)
+}
+
+// Types not supported at top level by the Encoder.
+var unsupportedValues = []interface{}{
+ make(chan int),
+ func(a int) bool { return true },
+}
+
+func TestUnsupported(t *testing.T) {
+ var b bytes.Buffer
+ enc := NewEncoder(&b)
+ for _, v := range unsupportedValues {
+ err := enc.Encode(v)
+ if err == nil {
+ t.Errorf("expected error for %T; got none", v)
+ }
+ }
+}
+
+func encAndDec(in, out interface{}) error {
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ err := enc.Encode(in)
+ if err != nil {
+ return err
+ }
+ dec := NewDecoder(b)
+ err = dec.Decode(out)
+ if err != nil {
+ return err
+ }
+ return nil
+}
+
+func TestTypeToPtrType(t *testing.T) {
+ // Encode a T, decode a *T
+ type Type0 struct {
+ A int
+ }
+ t0 := Type0{7}
+ t0p := new(Type0)
+ if err := encAndDec(t0, t0p); err != nil {
+ t.Error(err)
+ }
+}
+
+func TestPtrTypeToType(t *testing.T) {
+ // Encode a *T, decode a T
+ type Type1 struct {
+ A uint
+ }
+ t1p := &Type1{17}
+ var t1 Type1
+ if err := encAndDec(t1, t1p); err != nil {
+ t.Error(err)
+ }
+}
+
+func TestTypeToPtrPtrPtrPtrType(t *testing.T) {
+ type Type2 struct {
+ A ****float64
+ }
+ t2 := Type2{}
+ t2.A = new(***float64)
+ *t2.A = new(**float64)
+ **t2.A = new(*float64)
+ ***t2.A = new(float64)
+ ****t2.A = 27.4
+ t2pppp := new(***Type2)
+ if err := encAndDec(t2, t2pppp); err != nil {
+ t.Fatal(err)
+ }
+ if ****(****t2pppp).A != ****t2.A {
+ t.Errorf("wrong value after decode: %g not %g", ****(****t2pppp).A, ****t2.A)
+ }
+}
+
+func TestSlice(t *testing.T) {
+ type Type3 struct {
+ A []string
+ }
+ t3p := &Type3{[]string{"hello", "world"}}
+ var t3 Type3
+ if err := encAndDec(t3, t3p); err != nil {
+ t.Error(err)
+ }
+}
+
+func TestValueError(t *testing.T) {
+ // Encode a *T, decode a T
+ type Type4 struct {
+ A int
+ }
+ t4p := &Type4{3}
+ var t4 Type4 // note: not a pointer.
+ if err := encAndDec(t4p, t4); err == nil || !strings.Contains(err.Error(), "pointer") {
+ t.Error("expected error about pointer; got", err)
+ }
+}
+
+func TestArray(t *testing.T) {
+ type Type5 struct {
+ A [3]string
+ B [3]byte
+ }
+ type Type6 struct {
+ A [2]string // can't hold t5.a
+ }
+ t5 := Type5{[3]string{"hello", ",", "world"}, [3]byte{1, 2, 3}}
+ var t5p Type5
+ if err := encAndDec(t5, &t5p); err != nil {
+ t.Error(err)
+ }
+ var t6 Type6
+ if err := encAndDec(t5, &t6); err == nil {
+ t.Error("should fail with mismatched array sizes")
+ }
+}
+
+func TestRecursiveMapType(t *testing.T) {
+ type recursiveMap map[string]recursiveMap
+ r1 := recursiveMap{"A": recursiveMap{"B": nil, "C": nil}, "D": nil}
+ r2 := make(recursiveMap)
+ if err := encAndDec(r1, &r2); err != nil {
+ t.Error(err)
+ }
+}
+
+func TestRecursiveSliceType(t *testing.T) {
+ type recursiveSlice []recursiveSlice
+ r1 := recursiveSlice{0: recursiveSlice{0: nil}, 1: nil}
+ r2 := make(recursiveSlice, 0)
+ if err := encAndDec(r1, &r2); err != nil {
+ t.Error(err)
+ }
+}
+
+// Regression test for bug: must send zero values inside arrays
+func TestDefaultsInArray(t *testing.T) {
+ type Type7 struct {
+ B []bool
+ I []int
+ S []string
+ F []float64
+ }
+ t7 := Type7{
+ []bool{false, false, true},
+ []int{0, 0, 1},
+ []string{"hi", "", "there"},
+ []float64{0, 0, 1},
+ }
+ var t7p Type7
+ if err := encAndDec(t7, &t7p); err != nil {
+ t.Error(err)
+ }
+}
+
+var testInt int
+var testFloat32 float32
+var testString string
+var testSlice []string
+var testMap map[string]int
+var testArray [7]int
+
+type SingleTest struct {
+ in interface{}
+ out interface{}
+ err string
+}
+
+var singleTests = []SingleTest{
+ {17, &testInt, ""},
+ {float32(17.5), &testFloat32, ""},
+ {"bike shed", &testString, ""},
+ {[]string{"bike", "shed", "paint", "color"}, &testSlice, ""},
+ {map[string]int{"seven": 7, "twelve": 12}, &testMap, ""},
+ {[7]int{4, 55, 0, 0, 0, 0, 0}, &testArray, ""}, // case that once triggered a bug
+ {[7]int{4, 55, 1, 44, 22, 66, 1234}, &testArray, ""},
+
+ // Decode errors
+ {172, &testFloat32, "type"},
+}
+
+func TestSingletons(t *testing.T) {
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ dec := NewDecoder(b)
+ for _, test := range singleTests {
+ b.Reset()
+ err := enc.Encode(test.in)
+ if err != nil {
+ t.Errorf("error encoding %v: %s", test.in, err)
+ continue
+ }
+ err = dec.Decode(test.out)
+ switch {
+ case err != nil && test.err == "":
+ t.Errorf("error decoding %v: %s", test.in, err)
+ continue
+ case err == nil && test.err != "":
+ t.Errorf("expected error decoding %v: %s", test.in, test.err)
+ continue
+ case err != nil && test.err != "":
+ if !strings.Contains(err.Error(), test.err) {
+ t.Errorf("wrong error decoding %v: wanted %s, got %v", test.in, test.err, err)
+ }
+ continue
+ }
+ // Get rid of the pointer in the rhs
+ val := reflect.ValueOf(test.out).Elem().Interface()
+ if !reflect.DeepEqual(test.in, val) {
+ t.Errorf("decoding singleton: expected %v got %v", test.in, val)
+ }
+ }
+}
+
+func TestStructNonStruct(t *testing.T) {
+ type Struct struct {
+ A string
+ }
+ type NonStruct string
+ s := Struct{"hello"}
+ var sp Struct
+ if err := encAndDec(s, &sp); err != nil {
+ t.Error(err)
+ }
+ var ns NonStruct
+ if err := encAndDec(s, &ns); err == nil {
+ t.Error("should get error for struct/non-struct")
+ } else if !strings.Contains(err.Error(), "type") {
+ t.Error("for struct/non-struct expected type error; got", err)
+ }
+ // Now try the other way
+ var nsp NonStruct
+ if err := encAndDec(ns, &nsp); err != nil {
+ t.Error(err)
+ }
+ if err := encAndDec(ns, &s); err == nil {
+ t.Error("should get error for non-struct/struct")
+ } else if !strings.Contains(err.Error(), "type") {
+ t.Error("for non-struct/struct expected type error; got", err)
+ }
+}
+
+type interfaceIndirectTestI interface {
+ F() bool
+}
+
+type interfaceIndirectTestT struct{}
+
+func (this *interfaceIndirectTestT) F() bool {
+ return true
+}
+
+// A version of a bug reported on golang-nuts. Also tests top-level
+// slice of interfaces. The issue was registering *T caused T to be
+// stored as the concrete type.
+func TestInterfaceIndirect(t *testing.T) {
+ Register(&interfaceIndirectTestT{})
+ b := new(bytes.Buffer)
+ w := []interfaceIndirectTestI{&interfaceIndirectTestT{}}
+ err := NewEncoder(b).Encode(w)
+ if err != nil {
+ t.Fatal("encode error:", err)
+ }
+
+ var r []interfaceIndirectTestI
+ err = NewDecoder(b).Decode(&r)
+ if err != nil {
+ t.Fatal("decode error:", err)
+ }
+}
+
+// Now follow various tests that decode into things that can't represent the
+// encoded value, all of which should be legal.
+
+// Also, when the ignored object contains an interface value, it may define
+// types. Make sure that skipping the value still defines the types by using
+// the encoder/decoder pair to send a value afterwards. If an interface
+// is sent, its type in the test is always NewType0, so this checks that the
+// encoder and decoder don't skew with respect to type definitions.
+
+type Struct0 struct {
+ I interface{}
+}
+
+type NewType0 struct {
+ S string
+}
+
+type ignoreTest struct {
+ in, out interface{}
+}
+
+var ignoreTests = []ignoreTest{
+ // Decode normal struct into an empty struct
+ {&struct{ A int }{23}, &struct{}{}},
+ // Decode normal struct into a nil.
+ {&struct{ A int }{23}, nil},
+ // Decode singleton string into a nil.
+ {"hello, world", nil},
+ // Decode singleton slice into a nil.
+ {[]int{1, 2, 3, 4}, nil},
+ // Decode struct containing an interface into a nil.
+ {&Struct0{&NewType0{"value0"}}, nil},
+ // Decode singleton slice of interfaces into a nil.
+ {[]interface{}{"hi", &NewType0{"value1"}, 23}, nil},
+}
+
+func TestDecodeIntoNothing(t *testing.T) {
+ Register(new(NewType0))
+ for i, test := range ignoreTests {
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ err := enc.Encode(test.in)
+ if err != nil {
+ t.Errorf("%d: encode error %s:", i, err)
+ continue
+ }
+ dec := NewDecoder(b)
+ err = dec.Decode(test.out)
+ if err != nil {
+ t.Errorf("%d: decode error: %s", i, err)
+ continue
+ }
+ // Now see if the encoder and decoder are in a consistent state.
+ str := fmt.Sprintf("Value %d", i)
+ err = enc.Encode(&NewType0{str})
+ if err != nil {
+ t.Fatalf("%d: NewType0 encode error: %s", i, err)
+ }
+ ns := new(NewType0)
+ err = dec.Decode(ns)
+ if err != nil {
+ t.Fatalf("%d: NewType0 decode error: %s", i, err)
+ }
+ if ns.S != str {
+ t.Fatalf("%d: expected %q got %q", i, str, ns.S)
+ }
+ }
+}
+
+func TestIgnoreRecursiveType(t *testing.T) {
+ // It's hard to build a self-contained test for this because
+ // we can't build compatible types in one package with
+ // different items so something is ignored. Here is
+ // some data that represents, according to debug.go:
+ // type definition {
+ // slice "recursiveSlice" id=106
+ // elem id=106
+ // }
+ data := []byte{
+ 0x1d, 0xff, 0xd3, 0x02, 0x01, 0x01, 0x0e, 0x72,
+ 0x65, 0x63, 0x75, 0x72, 0x73, 0x69, 0x76, 0x65,
+ 0x53, 0x6c, 0x69, 0x63, 0x65, 0x01, 0xff, 0xd4,
+ 0x00, 0x01, 0xff, 0xd4, 0x00, 0x00, 0x07, 0xff,
+ 0xd4, 0x00, 0x02, 0x01, 0x00, 0x00,
+ }
+ dec := NewDecoder(bytes.NewReader(data))
+ // Issue 10415: This caused infinite recursion.
+ err := dec.Decode(nil)
+ if err != nil {
+ t.Fatal(err)
+ }
+}
+
+// Another bug from golang-nuts, involving nested interfaces.
+type Bug0Outer struct {
+ Bug0Field interface{}
+}
+
+type Bug0Inner struct {
+ A int
+}
+
+func TestNestedInterfaces(t *testing.T) {
+ var buf bytes.Buffer
+ e := NewEncoder(&buf)
+ d := NewDecoder(&buf)
+ Register(new(Bug0Outer))
+ Register(new(Bug0Inner))
+ f := &Bug0Outer{&Bug0Outer{&Bug0Inner{7}}}
+ var v interface{} = f
+ err := e.Encode(&v)
+ if err != nil {
+ t.Fatal("Encode:", err)
+ }
+ err = d.Decode(&v)
+ if err != nil {
+ t.Fatal("Decode:", err)
+ }
+ // Make sure it decoded correctly.
+ outer1, ok := v.(*Bug0Outer)
+ if !ok {
+ t.Fatalf("v not Bug0Outer: %T", v)
+ }
+ outer2, ok := outer1.Bug0Field.(*Bug0Outer)
+ if !ok {
+ t.Fatalf("v.Bug0Field not Bug0Outer: %T", outer1.Bug0Field)
+ }
+ inner, ok := outer2.Bug0Field.(*Bug0Inner)
+ if !ok {
+ t.Fatalf("v.Bug0Field.Bug0Field not Bug0Inner: %T", outer2.Bug0Field)
+ }
+ if inner.A != 7 {
+ t.Fatalf("final value %d; expected %d", inner.A, 7)
+ }
+}
+
+// The bugs keep coming. We forgot to send map subtypes before the map.
+
+type Bug1Elem struct {
+ Name string
+ Id int
+}
+
+type Bug1StructMap map[string]Bug1Elem
+
+func TestMapBug1(t *testing.T) {
+ in := make(Bug1StructMap)
+ in["val1"] = Bug1Elem{"elem1", 1}
+ in["val2"] = Bug1Elem{"elem2", 2}
+
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ err := enc.Encode(in)
+ if err != nil {
+ t.Fatal("encode:", err)
+ }
+ dec := NewDecoder(b)
+ out := make(Bug1StructMap)
+ err = dec.Decode(&out)
+ if err != nil {
+ t.Fatal("decode:", err)
+ }
+ if !reflect.DeepEqual(in, out) {
+ t.Errorf("mismatch: %v %v", in, out)
+ }
+}
+
+func TestGobMapInterfaceEncode(t *testing.T) {
+ m := map[string]interface{}{
+ "up": uintptr(0),
+ "i0": []int{-1},
+ "i1": []int8{-1},
+ "i2": []int16{-1},
+ "i3": []int32{-1},
+ "i4": []int64{-1},
+ "u0": []uint{1},
+ "u1": []uint8{1},
+ "u2": []uint16{1},
+ "u3": []uint32{1},
+ "u4": []uint64{1},
+ "f0": []float32{1},
+ "f1": []float64{1},
+ "c0": []complex64{complex(2, -2)},
+ "c1": []complex128{complex(2, float64(-2))},
+ "us": []uintptr{0},
+ "bo": []bool{false},
+ "st": []string{"s"},
+ }
+ enc := NewEncoder(new(bytes.Buffer))
+ err := enc.Encode(m)
+ if err != nil {
+ t.Errorf("encode map: %s", err)
+ }
+}
+
+func TestSliceReusesMemory(t *testing.T) {
+ buf := new(bytes.Buffer)
+ // Bytes
+ {
+ x := []byte("abcd")
+ enc := NewEncoder(buf)
+ err := enc.Encode(x)
+ if err != nil {
+ t.Errorf("bytes: encode: %s", err)
+ }
+ // Decode into y, which is big enough.
+ y := []byte("ABCDE")
+ addr := &y[0]
+ dec := NewDecoder(buf)
+ err = dec.Decode(&y)
+ if err != nil {
+ t.Fatal("bytes: decode:", err)
+ }
+ if !bytes.Equal(x, y) {
+ t.Errorf("bytes: expected %q got %q\n", x, y)
+ }
+ if addr != &y[0] {
+ t.Errorf("bytes: unnecessary reallocation")
+ }
+ }
+ // general slice
+ {
+ x := []rune("abcd")
+ enc := NewEncoder(buf)
+ err := enc.Encode(x)
+ if err != nil {
+ t.Errorf("ints: encode: %s", err)
+ }
+ // Decode into y, which is big enough.
+ y := []rune("ABCDE")
+ addr := &y[0]
+ dec := NewDecoder(buf)
+ err = dec.Decode(&y)
+ if err != nil {
+ t.Fatal("ints: decode:", err)
+ }
+ if !reflect.DeepEqual(x, y) {
+ t.Errorf("ints: expected %q got %q\n", x, y)
+ }
+ if addr != &y[0] {
+ t.Errorf("ints: unnecessary reallocation")
+ }
+ }
+}
+
+// Used to crash: negative count in recvMessage.
+func TestBadCount(t *testing.T) {
+ b := []byte{0xfb, 0xa5, 0x82, 0x2f, 0xca, 0x1}
+ if err := NewDecoder(bytes.NewReader(b)).Decode(nil); err == nil {
+ t.Error("expected error from bad count")
+ } else if err.Error() != errBadCount.Error() {
+ t.Error("expected bad count error; got", err)
+ }
+}
+
+// Verify that sequential Decoders built on a single input will
+// succeed if the input implements ReadByte and there is no
+// type information in the stream.
+func TestSequentialDecoder(t *testing.T) {
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ const count = 10
+ for i := 0; i < count; i++ {
+ s := fmt.Sprintf("%d", i)
+ if err := enc.Encode(s); err != nil {
+ t.Error("encoder fail:", err)
+ }
+ }
+ for i := 0; i < count; i++ {
+ dec := NewDecoder(b)
+ var s string
+ if err := dec.Decode(&s); err != nil {
+ t.Fatal("decoder fail:", err)
+ }
+ if s != fmt.Sprintf("%d", i) {
+ t.Fatalf("decode expected %d got %s", i, s)
+ }
+ }
+}
+
+// Should be able to have unrepresentable fields (chan, func, *chan etc.); we just ignore them.
+type Bug2 struct {
+ A int
+ C chan int
+ CP *chan int
+ F func()
+ FPP **func()
+}
+
+func TestChanFuncIgnored(t *testing.T) {
+ c := make(chan int)
+ f := func() {}
+ fp := &f
+ b0 := Bug2{23, c, &c, f, &fp}
+ var buf bytes.Buffer
+ enc := NewEncoder(&buf)
+ if err := enc.Encode(b0); err != nil {
+ t.Fatal("error encoding:", err)
+ }
+ var b1 Bug2
+ err := NewDecoder(&buf).Decode(&b1)
+ if err != nil {
+ t.Fatal("decode:", err)
+ }
+ if b1.A != b0.A {
+ t.Fatalf("got %d want %d", b1.A, b0.A)
+ }
+ if b1.C != nil || b1.CP != nil || b1.F != nil || b1.FPP != nil {
+ t.Fatal("unexpected value for chan or func")
+ }
+}
+
+func TestSliceIncompatibility(t *testing.T) {
+ var in = []byte{1, 2, 3}
+ var out []int
+ if err := encAndDec(in, &out); err == nil {
+ t.Error("expected compatibility error")
+ }
+}
+
+// Mutually recursive slices of structs caused problems.
+type Bug3 struct {
+ Num int
+ Children []*Bug3
+}
+
+func TestGobPtrSlices(t *testing.T) {
+ in := []*Bug3{
+ {1, nil},
+ {2, nil},
+ }
+ b := new(bytes.Buffer)
+ err := NewEncoder(b).Encode(&in)
+ if err != nil {
+ t.Fatal("encode:", err)
+ }
+
+ var out []*Bug3
+ err = NewDecoder(b).Decode(&out)
+ if err != nil {
+ t.Fatal("decode:", err)
+ }
+ if !reflect.DeepEqual(in, out) {
+ t.Fatalf("got %v; wanted %v", out, in)
+ }
+}
+
+// getDecEnginePtr cached engine for ut.base instead of ut.user so we passed
+// a *map and then tried to reuse its engine to decode the inner map.
+func TestPtrToMapOfMap(t *testing.T) {
+ Register(make(map[string]interface{}))
+ subdata := make(map[string]interface{})
+ subdata["bar"] = "baz"
+ data := make(map[string]interface{})
+ data["foo"] = subdata
+
+ b := new(bytes.Buffer)
+ err := NewEncoder(b).Encode(data)
+ if err != nil {
+ t.Fatal("encode:", err)
+ }
+ var newData map[string]interface{}
+ err = NewDecoder(b).Decode(&newData)
+ if err != nil {
+ t.Fatal("decode:", err)
+ }
+ if !reflect.DeepEqual(data, newData) {
+ t.Fatalf("expected %v got %v", data, newData)
+ }
+}
+
+// Test that untyped nils generate an error, not a panic.
+// See Issue 16204.
+func TestCatchInvalidNilValue(t *testing.T) {
+ encodeErr, panicErr := encodeAndRecover(nil)
+ if panicErr != nil {
+ t.Fatalf("panicErr=%v, should not panic encoding untyped nil", panicErr)
+ }
+ if encodeErr == nil {
+ t.Errorf("got err=nil, want non-nil error when encoding untyped nil value")
+ } else if !strings.Contains(encodeErr.Error(), "nil value") {
+ t.Errorf("expected 'nil value' error; got err=%v", encodeErr)
+ }
+}
+
+// A top-level nil pointer generates a panic with a helpful string-valued message.
+func TestTopLevelNilPointer(t *testing.T) {
+ var ip *int
+ encodeErr, panicErr := encodeAndRecover(ip)
+ if encodeErr != nil {
+ t.Fatal("error in encode:", encodeErr)
+ }
+ if panicErr == nil {
+ t.Fatal("top-level nil pointer did not panic")
+ }
+ errMsg := panicErr.Error()
+ if !strings.Contains(errMsg, "nil pointer") {
+ t.Fatal("expected nil pointer error, got:", errMsg)
+ }
+}
+
+func encodeAndRecover(value interface{}) (encodeErr, panicErr error) {
+ defer func() {
+ e := recover()
+ if e != nil {
+ switch err := e.(type) {
+ case error:
+ panicErr = err
+ default:
+ panicErr = fmt.Errorf("%v", err)
+ }
+ }
+ }()
+
+ encodeErr = NewEncoder(io.Discard).Encode(value)
+ return
+}
+
+func TestNilPointerPanics(t *testing.T) {
+ var (
+ nilStringPtr *string
+ intMap = make(map[int]int)
+ intMapPtr = &intMap
+ nilIntMapPtr *map[int]int
+ zero int
+ nilBoolChannel chan bool
+ nilBoolChannelPtr *chan bool
+ nilStringSlice []string
+ stringSlice = make([]string, 1)
+ nilStringSlicePtr *[]string
+ )
+
+ testCases := []struct {
+ value interface{}
+ mustPanic bool
+ }{
+ {nilStringPtr, true},
+ {intMap, false},
+ {intMapPtr, false},
+ {nilIntMapPtr, true},
+ {zero, false},
+ {nilStringSlice, false},
+ {stringSlice, false},
+ {nilStringSlicePtr, true},
+ {nilBoolChannel, false},
+ {nilBoolChannelPtr, true},
+ }
+
+ for _, tt := range testCases {
+ _, panicErr := encodeAndRecover(tt.value)
+ if tt.mustPanic {
+ if panicErr == nil {
+ t.Errorf("expected panic with input %#v, did not panic", tt.value)
+ }
+ continue
+ }
+ if panicErr != nil {
+ t.Fatalf("expected no panic with input %#v, got panic=%v", tt.value, panicErr)
+ }
+ }
+}
+
+func TestNilPointerInsideInterface(t *testing.T) {
+ var ip *int
+ si := struct {
+ I interface{}
+ }{
+ I: ip,
+ }
+ buf := new(bytes.Buffer)
+ err := NewEncoder(buf).Encode(si)
+ if err == nil {
+ t.Fatal("expected error, got none")
+ }
+ errMsg := err.Error()
+ if !strings.Contains(errMsg, "nil pointer") || !strings.Contains(errMsg, "interface") {
+ t.Fatal("expected error about nil pointer and interface, got:", errMsg)
+ }
+}
+
+type Bug4Public struct {
+ Name string
+ Secret Bug4Secret
+}
+
+type Bug4Secret struct {
+ a int // error: no exported fields.
+}
+
+// Test that a failed compilation doesn't leave around an executable encoder.
+// Issue 3723.
+func TestMutipleEncodingsOfBadType(t *testing.T) {
+ x := Bug4Public{
+ Name: "name",
+ Secret: Bug4Secret{1},
+ }
+ buf := new(bytes.Buffer)
+ enc := NewEncoder(buf)
+ err := enc.Encode(x)
+ if err == nil {
+ t.Fatal("first encoding: expected error")
+ }
+ buf.Reset()
+ enc = NewEncoder(buf)
+ err = enc.Encode(x)
+ if err == nil {
+ t.Fatal("second encoding: expected error")
+ }
+ if !strings.Contains(err.Error(), "no exported fields") {
+ t.Errorf("expected error about no exported fields; got %v", err)
+ }
+}
+
+// There was an error check comparing the length of the input with the
+// length of the slice being decoded. It was wrong because the next
+// thing in the input might be a type definition, which would lead to
+// an incorrect length check. This test reproduces the corner case.
+
+type Z struct {
+}
+
+func Test29ElementSlice(t *testing.T) {
+ Register(Z{})
+ src := make([]interface{}, 100) // Size needs to be bigger than size of type definition.
+ for i := range src {
+ src[i] = Z{}
+ }
+ buf := new(bytes.Buffer)
+ err := NewEncoder(buf).Encode(src)
+ if err != nil {
+ t.Fatalf("encode: %v", err)
+ return
+ }
+
+ var dst []interface{}
+ err = NewDecoder(buf).Decode(&dst)
+ if err != nil {
+ t.Errorf("decode: %v", err)
+ return
+ }
+}
+
+// Don't crash, just give error when allocating a huge slice.
+// Issue 8084.
+func TestErrorForHugeSlice(t *testing.T) {
+ // Encode an int slice.
+ buf := new(bytes.Buffer)
+ slice := []int{1, 1, 1, 1, 1, 1, 1, 1, 1, 1}
+ err := NewEncoder(buf).Encode(slice)
+ if err != nil {
+ t.Fatal("encode:", err)
+ }
+ // Reach into the buffer and smash the count to make the encoded slice very long.
+ buf.Bytes()[buf.Len()-len(slice)-1] = 0xfa
+ // Decode and see error.
+ err = NewDecoder(buf).Decode(&slice)
+ if err == nil {
+ t.Fatal("decode: no error")
+ }
+ if !strings.Contains(err.Error(), "slice too big") {
+ t.Fatalf("decode: expected slice too big error, got %s", err.Error())
+ }
+}
+
+type badDataTest struct {
+ input string // The input encoded as a hex string.
+ error string // A substring of the error that should result.
+ data interface{} // What to decode into.
+}
+
+var badDataTests = []badDataTest{
+ {"", "EOF", nil},
+ {"7F6869", "unexpected EOF", nil},
+ {"036e6f77206973207468652074696d6520666f7220616c6c20676f6f64206d656e", "unknown type id", new(ET2)},
+ {"0424666f6f", "field numbers out of bounds", new(ET2)}, // Issue 6323.
+ {"05100028557b02027f8302", "interface encoding", nil}, // Issue 10270.
+ // Issue 10273.
+ {"130a00fb5dad0bf8ff020263e70002fa28020202a89859", "slice length too large", nil},
+ {"0f1000fb285d003316020735ff023a65c5", "interface encoding", nil},
+ {"03fffb0616fffc00f902ff02ff03bf005d02885802a311a8120228022c028ee7", "GobDecoder", nil},
+ // Issue 10491.
+ {"10fe010f020102fe01100001fe010e000016fe010d030102fe010e00010101015801fe01100000000bfe011000f85555555555555555", "exceeds input size", nil},
+}
+
+// TestBadData tests that various problems caused by malformed input
+// are caught as errors and do not cause panics.
+func TestBadData(t *testing.T) {
+ for i, test := range badDataTests {
+ data, err := hex.DecodeString(test.input)
+ if err != nil {
+ t.Fatalf("#%d: hex error: %s", i, err)
+ }
+ d := NewDecoder(bytes.NewReader(data))
+ err = d.Decode(test.data)
+ if err == nil {
+ t.Errorf("decode: no error")
+ continue
+ }
+ if !strings.Contains(err.Error(), test.error) {
+ t.Errorf("#%d: decode: expected %q error, got %s", i, test.error, err.Error())
+ }
+ }
+}
+
+func TestDecodeErrorMultipleTypes(t *testing.T) {
+ type Test struct {
+ A string
+ B int
+ }
+ var b bytes.Buffer
+ NewEncoder(&b).Encode(Test{"one", 1})
+
+ var result, result2 Test
+ dec := NewDecoder(&b)
+ err := dec.Decode(&result)
+ if err != nil {
+ t.Errorf("decode: unexpected error %v", err)
+ }
+
+ b.Reset()
+ NewEncoder(&b).Encode(Test{"two", 2})
+ err = dec.Decode(&result2)
+ if err == nil {
+ t.Errorf("decode: expected duplicate type error, got nil")
+ } else if !strings.Contains(err.Error(), "duplicate type") {
+ t.Errorf("decode: expected duplicate type error, got %s", err.Error())
+ }
+}
diff --git a/src/encoding/gob/error.go b/src/encoding/gob/error.go
new file mode 100644
index 0000000..949333b
--- /dev/null
+++ b/src/encoding/gob/error.go
@@ -0,0 +1,42 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gob
+
+import "fmt"
+
+// Errors in decoding and encoding are handled using panic and recover.
+// Panics caused by user error (that is, everything except run-time panics
+// such as "index out of bounds" errors) do not leave the file that caused
+// them, but are instead turned into plain error returns. Encoding and
+// decoding functions and methods that do not return an error either use
+// panic to report an error or are guaranteed error-free.
+
+// A gobError is used to distinguish errors (panics) generated in this package.
+type gobError struct {
+ err error
+}
+
+// errorf is like error_ but takes Printf-style arguments to construct an error.
+// It always prefixes the message with "gob: ".
+func errorf(format string, args ...interface{}) {
+ error_(fmt.Errorf("gob: "+format, args...))
+}
+
+// error wraps the argument error and uses it as the argument to panic.
+func error_(err error) {
+ panic(gobError{err})
+}
+
+// catchError is meant to be used as a deferred function to turn a panic(gobError) into a
+// plain error. It overwrites the error return of the function that deferred its call.
+func catchError(err *error) {
+ if e := recover(); e != nil {
+ ge, ok := e.(gobError)
+ if !ok {
+ panic(e)
+ }
+ *err = ge.err
+ }
+}
diff --git a/src/encoding/gob/example_encdec_test.go b/src/encoding/gob/example_encdec_test.go
new file mode 100644
index 0000000..e45ad4c
--- /dev/null
+++ b/src/encoding/gob/example_encdec_test.go
@@ -0,0 +1,61 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gob_test
+
+import (
+ "bytes"
+ "encoding/gob"
+ "fmt"
+ "log"
+)
+
+// The Vector type has unexported fields, which the package cannot access.
+// We therefore write a BinaryMarshal/BinaryUnmarshal method pair to allow us
+// to send and receive the type with the gob package. These interfaces are
+// defined in the "encoding" package.
+// We could equivalently use the locally defined GobEncode/GobDecoder
+// interfaces.
+type Vector struct {
+ x, y, z int
+}
+
+func (v Vector) MarshalBinary() ([]byte, error) {
+ // A simple encoding: plain text.
+ var b bytes.Buffer
+ fmt.Fprintln(&b, v.x, v.y, v.z)
+ return b.Bytes(), nil
+}
+
+// UnmarshalBinary modifies the receiver so it must take a pointer receiver.
+func (v *Vector) UnmarshalBinary(data []byte) error {
+ // A simple encoding: plain text.
+ b := bytes.NewBuffer(data)
+ _, err := fmt.Fscanln(b, &v.x, &v.y, &v.z)
+ return err
+}
+
+// This example transmits a value that implements the custom encoding and decoding methods.
+func Example_encodeDecode() {
+ var network bytes.Buffer // Stand-in for the network.
+
+ // Create an encoder and send a value.
+ enc := gob.NewEncoder(&network)
+ err := enc.Encode(Vector{3, 4, 5})
+ if err != nil {
+ log.Fatal("encode:", err)
+ }
+
+ // Create a decoder and receive a value.
+ dec := gob.NewDecoder(&network)
+ var v Vector
+ err = dec.Decode(&v)
+ if err != nil {
+ log.Fatal("decode:", err)
+ }
+ fmt.Println(v)
+
+ // Output:
+ // {3 4 5}
+}
diff --git a/src/encoding/gob/example_interface_test.go b/src/encoding/gob/example_interface_test.go
new file mode 100644
index 0000000..cf5ba38
--- /dev/null
+++ b/src/encoding/gob/example_interface_test.go
@@ -0,0 +1,81 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gob_test
+
+import (
+ "bytes"
+ "encoding/gob"
+ "fmt"
+ "log"
+ "math"
+)
+
+type Point struct {
+ X, Y int
+}
+
+func (p Point) Hypotenuse() float64 {
+ return math.Hypot(float64(p.X), float64(p.Y))
+}
+
+type Pythagoras interface {
+ Hypotenuse() float64
+}
+
+// This example shows how to encode an interface value. The key
+// distinction from regular types is to register the concrete type that
+// implements the interface.
+func Example_interface() {
+ var network bytes.Buffer // Stand-in for the network.
+
+ // We must register the concrete type for the encoder and decoder (which would
+ // normally be on a separate machine from the encoder). On each end, this tells the
+ // engine which concrete type is being sent that implements the interface.
+ gob.Register(Point{})
+
+ // Create an encoder and send some values.
+ enc := gob.NewEncoder(&network)
+ for i := 1; i <= 3; i++ {
+ interfaceEncode(enc, Point{3 * i, 4 * i})
+ }
+
+ // Create a decoder and receive some values.
+ dec := gob.NewDecoder(&network)
+ for i := 1; i <= 3; i++ {
+ result := interfaceDecode(dec)
+ fmt.Println(result.Hypotenuse())
+ }
+
+ // Output:
+ // 5
+ // 10
+ // 15
+}
+
+// interfaceEncode encodes the interface value into the encoder.
+func interfaceEncode(enc *gob.Encoder, p Pythagoras) {
+ // The encode will fail unless the concrete type has been
+ // registered. We registered it in the calling function.
+
+ // Pass pointer to interface so Encode sees (and hence sends) a value of
+ // interface type. If we passed p directly it would see the concrete type instead.
+ // See the blog post, "The Laws of Reflection" for background.
+ err := enc.Encode(&p)
+ if err != nil {
+ log.Fatal("encode:", err)
+ }
+}
+
+// interfaceDecode decodes the next interface value from the stream and returns it.
+func interfaceDecode(dec *gob.Decoder) Pythagoras {
+ // The decode will fail unless the concrete type on the wire has been
+ // registered. We registered it in the calling function.
+ var p Pythagoras
+ err := dec.Decode(&p)
+ if err != nil {
+ log.Fatal("decode:", err)
+ }
+ return p
+}
diff --git a/src/encoding/gob/example_test.go b/src/encoding/gob/example_test.go
new file mode 100644
index 0000000..16b7123
--- /dev/null
+++ b/src/encoding/gob/example_test.go
@@ -0,0 +1,60 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gob_test
+
+import (
+ "bytes"
+ "encoding/gob"
+ "fmt"
+ "log"
+)
+
+type P struct {
+ X, Y, Z int
+ Name string
+}
+
+type Q struct {
+ X, Y *int32
+ Name string
+}
+
+// This example shows the basic usage of the package: Create an encoder,
+// transmit some values, receive them with a decoder.
+func Example_basic() {
+ // Initialize the encoder and decoder. Normally enc and dec would be
+ // bound to network connections and the encoder and decoder would
+ // run in different processes.
+ var network bytes.Buffer // Stand-in for a network connection
+ enc := gob.NewEncoder(&network) // Will write to network.
+ dec := gob.NewDecoder(&network) // Will read from network.
+
+ // Encode (send) some values.
+ err := enc.Encode(P{3, 4, 5, "Pythagoras"})
+ if err != nil {
+ log.Fatal("encode error:", err)
+ }
+ err = enc.Encode(P{1782, 1841, 1922, "Treehouse"})
+ if err != nil {
+ log.Fatal("encode error:", err)
+ }
+
+ // Decode (receive) and print the values.
+ var q Q
+ err = dec.Decode(&q)
+ if err != nil {
+ log.Fatal("decode error 1:", err)
+ }
+ fmt.Printf("%q: {%d, %d}\n", q.Name, *q.X, *q.Y)
+ err = dec.Decode(&q)
+ if err != nil {
+ log.Fatal("decode error 2:", err)
+ }
+ fmt.Printf("%q: {%d, %d}\n", q.Name, *q.X, *q.Y)
+
+ // Output:
+ // "Pythagoras": {3, 4}
+ // "Treehouse": {1782, 1841}
+}
diff --git a/src/encoding/gob/gobencdec_test.go b/src/encoding/gob/gobencdec_test.go
new file mode 100644
index 0000000..1b52ecc
--- /dev/null
+++ b/src/encoding/gob/gobencdec_test.go
@@ -0,0 +1,822 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file contains tests of the GobEncoder/GobDecoder support.
+
+package gob
+
+import (
+ "bytes"
+ "errors"
+ "fmt"
+ "io"
+ "net"
+ "reflect"
+ "strings"
+ "testing"
+ "time"
+)
+
+// Types that implement the GobEncoder/Decoder interfaces.
+
+type ByteStruct struct {
+ a byte // not an exported field
+}
+
+type StringStruct struct {
+ s string // not an exported field
+}
+
+type ArrayStruct struct {
+ a [8192]byte // not an exported field
+}
+
+type Gobber int
+
+type ValueGobber string // encodes with a value, decodes with a pointer.
+
+type BinaryGobber int
+
+type BinaryValueGobber string
+
+type TextGobber int
+
+type TextValueGobber string
+
+// The relevant methods
+
+func (g *ByteStruct) GobEncode() ([]byte, error) {
+ b := make([]byte, 3)
+ b[0] = g.a
+ b[1] = g.a + 1
+ b[2] = g.a + 2
+ return b, nil
+}
+
+func (g *ByteStruct) GobDecode(data []byte) error {
+ if g == nil {
+ return errors.New("NIL RECEIVER")
+ }
+ // Expect N sequential-valued bytes.
+ if len(data) == 0 {
+ return io.EOF
+ }
+ g.a = data[0]
+ for i, c := range data {
+ if c != g.a+byte(i) {
+ return errors.New("invalid data sequence")
+ }
+ }
+ return nil
+}
+
+func (g *StringStruct) GobEncode() ([]byte, error) {
+ return []byte(g.s), nil
+}
+
+func (g *StringStruct) GobDecode(data []byte) error {
+ // Expect N sequential-valued bytes.
+ if len(data) == 0 {
+ return io.EOF
+ }
+ a := data[0]
+ for i, c := range data {
+ if c != a+byte(i) {
+ return errors.New("invalid data sequence")
+ }
+ }
+ g.s = string(data)
+ return nil
+}
+
+func (a *ArrayStruct) GobEncode() ([]byte, error) {
+ return a.a[:], nil
+}
+
+func (a *ArrayStruct) GobDecode(data []byte) error {
+ if len(data) != len(a.a) {
+ return errors.New("wrong length in array decode")
+ }
+ copy(a.a[:], data)
+ return nil
+}
+
+func (g *Gobber) GobEncode() ([]byte, error) {
+ return []byte(fmt.Sprintf("VALUE=%d", *g)), nil
+}
+
+func (g *Gobber) GobDecode(data []byte) error {
+ _, err := fmt.Sscanf(string(data), "VALUE=%d", (*int)(g))
+ return err
+}
+
+func (g *BinaryGobber) MarshalBinary() ([]byte, error) {
+ return []byte(fmt.Sprintf("VALUE=%d", *g)), nil
+}
+
+func (g *BinaryGobber) UnmarshalBinary(data []byte) error {
+ _, err := fmt.Sscanf(string(data), "VALUE=%d", (*int)(g))
+ return err
+}
+
+func (g *TextGobber) MarshalText() ([]byte, error) {
+ return []byte(fmt.Sprintf("VALUE=%d", *g)), nil
+}
+
+func (g *TextGobber) UnmarshalText(data []byte) error {
+ _, err := fmt.Sscanf(string(data), "VALUE=%d", (*int)(g))
+ return err
+}
+
+func (v ValueGobber) GobEncode() ([]byte, error) {
+ return []byte(fmt.Sprintf("VALUE=%s", v)), nil
+}
+
+func (v *ValueGobber) GobDecode(data []byte) error {
+ _, err := fmt.Sscanf(string(data), "VALUE=%s", (*string)(v))
+ return err
+}
+
+func (v BinaryValueGobber) MarshalBinary() ([]byte, error) {
+ return []byte(fmt.Sprintf("VALUE=%s", v)), nil
+}
+
+func (v *BinaryValueGobber) UnmarshalBinary(data []byte) error {
+ _, err := fmt.Sscanf(string(data), "VALUE=%s", (*string)(v))
+ return err
+}
+
+func (v TextValueGobber) MarshalText() ([]byte, error) {
+ return []byte(fmt.Sprintf("VALUE=%s", v)), nil
+}
+
+func (v *TextValueGobber) UnmarshalText(data []byte) error {
+ _, err := fmt.Sscanf(string(data), "VALUE=%s", (*string)(v))
+ return err
+}
+
+// Structs that include GobEncodable fields.
+
+type GobTest0 struct {
+ X int // guarantee we have something in common with GobTest*
+ G *ByteStruct
+}
+
+type GobTest1 struct {
+ X int // guarantee we have something in common with GobTest*
+ G *StringStruct
+}
+
+type GobTest2 struct {
+ X int // guarantee we have something in common with GobTest*
+ G string // not a GobEncoder - should give us errors
+}
+
+type GobTest3 struct {
+ X int // guarantee we have something in common with GobTest*
+ G *Gobber
+ B *BinaryGobber
+ T *TextGobber
+}
+
+type GobTest4 struct {
+ X int // guarantee we have something in common with GobTest*
+ V ValueGobber
+ BV BinaryValueGobber
+ TV TextValueGobber
+}
+
+type GobTest5 struct {
+ X int // guarantee we have something in common with GobTest*
+ V *ValueGobber
+ BV *BinaryValueGobber
+ TV *TextValueGobber
+}
+
+type GobTest6 struct {
+ X int // guarantee we have something in common with GobTest*
+ V ValueGobber
+ W *ValueGobber
+ BV BinaryValueGobber
+ BW *BinaryValueGobber
+ TV TextValueGobber
+ TW *TextValueGobber
+}
+
+type GobTest7 struct {
+ X int // guarantee we have something in common with GobTest*
+ V *ValueGobber
+ W ValueGobber
+ BV *BinaryValueGobber
+ BW BinaryValueGobber
+ TV *TextValueGobber
+ TW TextValueGobber
+}
+
+type GobTestIgnoreEncoder struct {
+ X int // guarantee we have something in common with GobTest*
+}
+
+type GobTestValueEncDec struct {
+ X int // guarantee we have something in common with GobTest*
+ G StringStruct // not a pointer.
+}
+
+type GobTestIndirectEncDec struct {
+ X int // guarantee we have something in common with GobTest*
+ G ***StringStruct // indirections to the receiver.
+}
+
+type GobTestArrayEncDec struct {
+ X int // guarantee we have something in common with GobTest*
+ A ArrayStruct // not a pointer.
+}
+
+type GobTestIndirectArrayEncDec struct {
+ X int // guarantee we have something in common with GobTest*
+ A ***ArrayStruct // indirections to a large receiver.
+}
+
+func TestGobEncoderField(t *testing.T) {
+ b := new(bytes.Buffer)
+ // First a field that's a structure.
+ enc := NewEncoder(b)
+ err := enc.Encode(GobTest0{17, &ByteStruct{'A'}})
+ if err != nil {
+ t.Fatal("encode error:", err)
+ }
+ dec := NewDecoder(b)
+ x := new(GobTest0)
+ err = dec.Decode(x)
+ if err != nil {
+ t.Fatal("decode error:", err)
+ }
+ if x.G.a != 'A' {
+ t.Errorf("expected 'A' got %c", x.G.a)
+ }
+ // Now a field that's not a structure.
+ b.Reset()
+ gobber := Gobber(23)
+ bgobber := BinaryGobber(24)
+ tgobber := TextGobber(25)
+ err = enc.Encode(GobTest3{17, &gobber, &bgobber, &tgobber})
+ if err != nil {
+ t.Fatal("encode error:", err)
+ }
+ y := new(GobTest3)
+ err = dec.Decode(y)
+ if err != nil {
+ t.Fatal("decode error:", err)
+ }
+ if *y.G != 23 || *y.B != 24 || *y.T != 25 {
+ t.Errorf("expected '23 got %d", *y.G)
+ }
+}
+
+// Even though the field is a value, we can still take its address
+// and should be able to call the methods.
+func TestGobEncoderValueField(t *testing.T) {
+ b := new(bytes.Buffer)
+ // First a field that's a structure.
+ enc := NewEncoder(b)
+ err := enc.Encode(&GobTestValueEncDec{17, StringStruct{"HIJKL"}})
+ if err != nil {
+ t.Fatal("encode error:", err)
+ }
+ dec := NewDecoder(b)
+ x := new(GobTestValueEncDec)
+ err = dec.Decode(x)
+ if err != nil {
+ t.Fatal("decode error:", err)
+ }
+ if x.G.s != "HIJKL" {
+ t.Errorf("expected `HIJKL` got %s", x.G.s)
+ }
+}
+
+// GobEncode/Decode should work even if the value is
+// more indirect than the receiver.
+func TestGobEncoderIndirectField(t *testing.T) {
+ b := new(bytes.Buffer)
+ // First a field that's a structure.
+ enc := NewEncoder(b)
+ s := &StringStruct{"HIJKL"}
+ sp := &s
+ err := enc.Encode(GobTestIndirectEncDec{17, &sp})
+ if err != nil {
+ t.Fatal("encode error:", err)
+ }
+ dec := NewDecoder(b)
+ x := new(GobTestIndirectEncDec)
+ err = dec.Decode(x)
+ if err != nil {
+ t.Fatal("decode error:", err)
+ }
+ if (***x.G).s != "HIJKL" {
+ t.Errorf("expected `HIJKL` got %s", (***x.G).s)
+ }
+}
+
+// Test with a large field with methods.
+func TestGobEncoderArrayField(t *testing.T) {
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ var a GobTestArrayEncDec
+ a.X = 17
+ for i := range a.A.a {
+ a.A.a[i] = byte(i)
+ }
+ err := enc.Encode(&a)
+ if err != nil {
+ t.Fatal("encode error:", err)
+ }
+ dec := NewDecoder(b)
+ x := new(GobTestArrayEncDec)
+ err = dec.Decode(x)
+ if err != nil {
+ t.Fatal("decode error:", err)
+ }
+ for i, v := range x.A.a {
+ if v != byte(i) {
+ t.Errorf("expected %x got %x", byte(i), v)
+ break
+ }
+ }
+}
+
+// Test an indirection to a large field with methods.
+func TestGobEncoderIndirectArrayField(t *testing.T) {
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ var a GobTestIndirectArrayEncDec
+ a.X = 17
+ var array ArrayStruct
+ ap := &array
+ app := &ap
+ a.A = &app
+ for i := range array.a {
+ array.a[i] = byte(i)
+ }
+ err := enc.Encode(a)
+ if err != nil {
+ t.Fatal("encode error:", err)
+ }
+ dec := NewDecoder(b)
+ x := new(GobTestIndirectArrayEncDec)
+ err = dec.Decode(x)
+ if err != nil {
+ t.Fatal("decode error:", err)
+ }
+ for i, v := range (***x.A).a {
+ if v != byte(i) {
+ t.Errorf("expected %x got %x", byte(i), v)
+ break
+ }
+ }
+}
+
+// As long as the fields have the same name and implement the
+// interface, we can cross-connect them. Not sure it's useful
+// and may even be bad but it works and it's hard to prevent
+// without exposing the contents of the object, which would
+// defeat the purpose.
+func TestGobEncoderFieldsOfDifferentType(t *testing.T) {
+ // first, string in field to byte in field
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ err := enc.Encode(GobTest1{17, &StringStruct{"ABC"}})
+ if err != nil {
+ t.Fatal("encode error:", err)
+ }
+ dec := NewDecoder(b)
+ x := new(GobTest0)
+ err = dec.Decode(x)
+ if err != nil {
+ t.Fatal("decode error:", err)
+ }
+ if x.G.a != 'A' {
+ t.Errorf("expected 'A' got %c", x.G.a)
+ }
+ // now the other direction, byte in field to string in field
+ b.Reset()
+ err = enc.Encode(GobTest0{17, &ByteStruct{'X'}})
+ if err != nil {
+ t.Fatal("encode error:", err)
+ }
+ y := new(GobTest1)
+ err = dec.Decode(y)
+ if err != nil {
+ t.Fatal("decode error:", err)
+ }
+ if y.G.s != "XYZ" {
+ t.Fatalf("expected `XYZ` got %q", y.G.s)
+ }
+}
+
+// Test that we can encode a value and decode into a pointer.
+func TestGobEncoderValueEncoder(t *testing.T) {
+ // first, string in field to byte in field
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ err := enc.Encode(GobTest4{17, ValueGobber("hello"), BinaryValueGobber("Καλημέρα"), TextValueGobber("こんにちは")})
+ if err != nil {
+ t.Fatal("encode error:", err)
+ }
+ dec := NewDecoder(b)
+ x := new(GobTest5)
+ err = dec.Decode(x)
+ if err != nil {
+ t.Fatal("decode error:", err)
+ }
+ if *x.V != "hello" || *x.BV != "Καλημέρα" || *x.TV != "こんにちは" {
+ t.Errorf("expected `hello` got %s", *x.V)
+ }
+}
+
+// Test that we can use a value then a pointer type of a GobEncoder
+// in the same encoded value. Bug 4647.
+func TestGobEncoderValueThenPointer(t *testing.T) {
+ v := ValueGobber("forty-two")
+ w := ValueGobber("six-by-nine")
+ bv := BinaryValueGobber("1nanocentury")
+ bw := BinaryValueGobber("πseconds")
+ tv := TextValueGobber("gravitationalacceleration")
+ tw := TextValueGobber("π²ft/s²")
+
+ // this was a bug: encoding a GobEncoder by value before a GobEncoder
+ // pointer would cause duplicate type definitions to be sent.
+
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ if err := enc.Encode(GobTest6{42, v, &w, bv, &bw, tv, &tw}); err != nil {
+ t.Fatal("encode error:", err)
+ }
+ dec := NewDecoder(b)
+ x := new(GobTest6)
+ if err := dec.Decode(x); err != nil {
+ t.Fatal("decode error:", err)
+ }
+
+ if got, want := x.V, v; got != want {
+ t.Errorf("v = %q, want %q", got, want)
+ }
+ if got, want := x.W, w; got == nil {
+ t.Errorf("w = nil, want %q", want)
+ } else if *got != want {
+ t.Errorf("w = %q, want %q", *got, want)
+ }
+
+ if got, want := x.BV, bv; got != want {
+ t.Errorf("bv = %q, want %q", got, want)
+ }
+ if got, want := x.BW, bw; got == nil {
+ t.Errorf("bw = nil, want %q", want)
+ } else if *got != want {
+ t.Errorf("bw = %q, want %q", *got, want)
+ }
+
+ if got, want := x.TV, tv; got != want {
+ t.Errorf("tv = %q, want %q", got, want)
+ }
+ if got, want := x.TW, tw; got == nil {
+ t.Errorf("tw = nil, want %q", want)
+ } else if *got != want {
+ t.Errorf("tw = %q, want %q", *got, want)
+ }
+}
+
+// Test that we can use a pointer then a value type of a GobEncoder
+// in the same encoded value.
+func TestGobEncoderPointerThenValue(t *testing.T) {
+ v := ValueGobber("forty-two")
+ w := ValueGobber("six-by-nine")
+ bv := BinaryValueGobber("1nanocentury")
+ bw := BinaryValueGobber("πseconds")
+ tv := TextValueGobber("gravitationalacceleration")
+ tw := TextValueGobber("π²ft/s²")
+
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ if err := enc.Encode(GobTest7{42, &v, w, &bv, bw, &tv, tw}); err != nil {
+ t.Fatal("encode error:", err)
+ }
+ dec := NewDecoder(b)
+ x := new(GobTest7)
+ if err := dec.Decode(x); err != nil {
+ t.Fatal("decode error:", err)
+ }
+
+ if got, want := x.V, v; got == nil {
+ t.Errorf("v = nil, want %q", want)
+ } else if *got != want {
+ t.Errorf("v = %q, want %q", *got, want)
+ }
+ if got, want := x.W, w; got != want {
+ t.Errorf("w = %q, want %q", got, want)
+ }
+
+ if got, want := x.BV, bv; got == nil {
+ t.Errorf("bv = nil, want %q", want)
+ } else if *got != want {
+ t.Errorf("bv = %q, want %q", *got, want)
+ }
+ if got, want := x.BW, bw; got != want {
+ t.Errorf("bw = %q, want %q", got, want)
+ }
+
+ if got, want := x.TV, tv; got == nil {
+ t.Errorf("tv = nil, want %q", want)
+ } else if *got != want {
+ t.Errorf("tv = %q, want %q", *got, want)
+ }
+ if got, want := x.TW, tw; got != want {
+ t.Errorf("tw = %q, want %q", got, want)
+ }
+}
+
+func TestGobEncoderFieldTypeError(t *testing.T) {
+ // GobEncoder to non-decoder: error
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ err := enc.Encode(GobTest1{17, &StringStruct{"ABC"}})
+ if err != nil {
+ t.Fatal("encode error:", err)
+ }
+ dec := NewDecoder(b)
+ x := &GobTest2{}
+ err = dec.Decode(x)
+ if err == nil {
+ t.Fatal("expected decode error for mismatched fields (encoder to non-decoder)")
+ }
+ if !strings.Contains(err.Error(), "type") {
+ t.Fatal("expected type error; got", err)
+ }
+ // Non-encoder to GobDecoder: error
+ b.Reset()
+ err = enc.Encode(GobTest2{17, "ABC"})
+ if err != nil {
+ t.Fatal("encode error:", err)
+ }
+ y := &GobTest1{}
+ err = dec.Decode(y)
+ if err == nil {
+ t.Fatal("expected decode error for mismatched fields (non-encoder to decoder)")
+ }
+ if !strings.Contains(err.Error(), "type") {
+ t.Fatal("expected type error; got", err)
+ }
+}
+
+// Even though ByteStruct is a struct, it's treated as a singleton at the top level.
+func TestGobEncoderStructSingleton(t *testing.T) {
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ err := enc.Encode(&ByteStruct{'A'})
+ if err != nil {
+ t.Fatal("encode error:", err)
+ }
+ dec := NewDecoder(b)
+ x := new(ByteStruct)
+ err = dec.Decode(x)
+ if err != nil {
+ t.Fatal("decode error:", err)
+ }
+ if x.a != 'A' {
+ t.Errorf("expected 'A' got %c", x.a)
+ }
+}
+
+func TestGobEncoderNonStructSingleton(t *testing.T) {
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ var g Gobber = 1234
+ err := enc.Encode(&g)
+ if err != nil {
+ t.Fatal("encode error:", err)
+ }
+ dec := NewDecoder(b)
+ var x Gobber
+ err = dec.Decode(&x)
+ if err != nil {
+ t.Fatal("decode error:", err)
+ }
+ if x != 1234 {
+ t.Errorf("expected 1234 got %d", x)
+ }
+}
+
+func TestGobEncoderIgnoreStructField(t *testing.T) {
+ b := new(bytes.Buffer)
+ // First a field that's a structure.
+ enc := NewEncoder(b)
+ err := enc.Encode(GobTest0{17, &ByteStruct{'A'}})
+ if err != nil {
+ t.Fatal("encode error:", err)
+ }
+ dec := NewDecoder(b)
+ x := new(GobTestIgnoreEncoder)
+ err = dec.Decode(x)
+ if err != nil {
+ t.Fatal("decode error:", err)
+ }
+ if x.X != 17 {
+ t.Errorf("expected 17 got %c", x.X)
+ }
+}
+
+func TestGobEncoderIgnoreNonStructField(t *testing.T) {
+ b := new(bytes.Buffer)
+ // First a field that's a structure.
+ enc := NewEncoder(b)
+ gobber := Gobber(23)
+ bgobber := BinaryGobber(24)
+ tgobber := TextGobber(25)
+ err := enc.Encode(GobTest3{17, &gobber, &bgobber, &tgobber})
+ if err != nil {
+ t.Fatal("encode error:", err)
+ }
+ dec := NewDecoder(b)
+ x := new(GobTestIgnoreEncoder)
+ err = dec.Decode(x)
+ if err != nil {
+ t.Fatal("decode error:", err)
+ }
+ if x.X != 17 {
+ t.Errorf("expected 17 got %c", x.X)
+ }
+}
+
+func TestGobEncoderIgnoreNilEncoder(t *testing.T) {
+ b := new(bytes.Buffer)
+ // First a field that's a structure.
+ enc := NewEncoder(b)
+ err := enc.Encode(GobTest0{X: 18}) // G is nil
+ if err != nil {
+ t.Fatal("encode error:", err)
+ }
+ dec := NewDecoder(b)
+ x := new(GobTest0)
+ err = dec.Decode(x)
+ if err != nil {
+ t.Fatal("decode error:", err)
+ }
+ if x.X != 18 {
+ t.Errorf("expected x.X = 18, got %v", x.X)
+ }
+ if x.G != nil {
+ t.Errorf("expected x.G = nil, got %v", x.G)
+ }
+}
+
+type gobDecoderBug0 struct {
+ foo, bar string
+}
+
+func (br *gobDecoderBug0) String() string {
+ return br.foo + "-" + br.bar
+}
+
+func (br *gobDecoderBug0) GobEncode() ([]byte, error) {
+ return []byte(br.String()), nil
+}
+
+func (br *gobDecoderBug0) GobDecode(b []byte) error {
+ br.foo = "foo"
+ br.bar = "bar"
+ return nil
+}
+
+// This was a bug: the receiver has a different indirection level
+// than the variable.
+func TestGobEncoderExtraIndirect(t *testing.T) {
+ gdb := &gobDecoderBug0{"foo", "bar"}
+ buf := new(bytes.Buffer)
+ e := NewEncoder(buf)
+ if err := e.Encode(gdb); err != nil {
+ t.Fatalf("encode: %v", err)
+ }
+ d := NewDecoder(buf)
+ var got *gobDecoderBug0
+ if err := d.Decode(&got); err != nil {
+ t.Fatalf("decode: %v", err)
+ }
+ if got.foo != gdb.foo || got.bar != gdb.bar {
+ t.Errorf("got = %q, want %q", got, gdb)
+ }
+}
+
+// Another bug: this caused a crash with the new Go1 Time type.
+// We throw in a gob-encoding array, to test another case of isZero,
+// and a struct containing a nil interface, to test a third.
+type isZeroBug struct {
+ T time.Time
+ S string
+ I int
+ A isZeroBugArray
+ F isZeroBugInterface
+}
+
+type isZeroBugArray [2]uint8
+
+// Receiver is value, not pointer, to test isZero of array.
+func (a isZeroBugArray) GobEncode() (b []byte, e error) {
+ b = append(b, a[:]...)
+ return b, nil
+}
+
+func (a *isZeroBugArray) GobDecode(data []byte) error {
+ if len(data) != len(a) {
+ return io.EOF
+ }
+ a[0] = data[0]
+ a[1] = data[1]
+ return nil
+}
+
+type isZeroBugInterface struct {
+ I interface{}
+}
+
+func (i isZeroBugInterface) GobEncode() (b []byte, e error) {
+ return []byte{}, nil
+}
+
+func (i *isZeroBugInterface) GobDecode(data []byte) error {
+ return nil
+}
+
+func TestGobEncodeIsZero(t *testing.T) {
+ x := isZeroBug{time.Unix(1e9, 0), "hello", -55, isZeroBugArray{1, 2}, isZeroBugInterface{}}
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ err := enc.Encode(x)
+ if err != nil {
+ t.Fatal("encode:", err)
+ }
+ var y isZeroBug
+ dec := NewDecoder(b)
+ err = dec.Decode(&y)
+ if err != nil {
+ t.Fatal("decode:", err)
+ }
+ if x != y {
+ t.Fatalf("%v != %v", x, y)
+ }
+}
+
+func TestGobEncodePtrError(t *testing.T) {
+ var err error
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ err = enc.Encode(&err)
+ if err != nil {
+ t.Fatal("encode:", err)
+ }
+ dec := NewDecoder(b)
+ err2 := fmt.Errorf("foo")
+ err = dec.Decode(&err2)
+ if err != nil {
+ t.Fatal("decode:", err)
+ }
+ if err2 != nil {
+ t.Fatalf("expected nil, got %v", err2)
+ }
+}
+
+func TestNetIP(t *testing.T) {
+ // Encoding of net.IP{1,2,3,4} in Go 1.1.
+ enc := []byte{0x07, 0x0a, 0x00, 0x04, 0x01, 0x02, 0x03, 0x04}
+
+ var ip net.IP
+ err := NewDecoder(bytes.NewReader(enc)).Decode(&ip)
+ if err != nil {
+ t.Fatalf("decode: %v", err)
+ }
+ if ip.String() != "1.2.3.4" {
+ t.Errorf("decoded to %v, want 1.2.3.4", ip.String())
+ }
+}
+
+func TestIngoreDepthLimit(t *testing.T) {
+ // We don't test the actual depth limit because it requires building an
+ // extremely large message, which takes quite a while.
+ oldNestingDepth := maxIgnoreNestingDepth
+ maxIgnoreNestingDepth = 100
+ defer func() { maxIgnoreNestingDepth = oldNestingDepth }()
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ typ := reflect.TypeOf(int(0))
+ nested := reflect.ArrayOf(1, typ)
+ for i := 0; i < 100; i++ {
+ nested = reflect.ArrayOf(1, nested)
+ }
+ badStruct := reflect.New(reflect.StructOf([]reflect.StructField{{Name: "F", Type: nested}}))
+ enc.Encode(badStruct.Interface())
+ dec := NewDecoder(b)
+ var output struct{ Hello int }
+ expectedErr := "invalid nesting depth"
+ if err := dec.Decode(&output); err == nil || err.Error() != expectedErr {
+ t.Errorf("Decode didn't fail with depth limit of 100: want %q, got %q", expectedErr, err)
+ }
+}
diff --git a/src/encoding/gob/timing_test.go b/src/encoding/gob/timing_test.go
new file mode 100644
index 0000000..3478bd2
--- /dev/null
+++ b/src/encoding/gob/timing_test.go
@@ -0,0 +1,314 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gob
+
+import (
+ "bytes"
+ "io"
+ "os"
+ "reflect"
+ "runtime"
+ "testing"
+)
+
+type Bench struct {
+ A int
+ B float64
+ C string
+ D []byte
+}
+
+func benchmarkEndToEnd(b *testing.B, ctor func() interface{}, pipe func() (r io.Reader, w io.Writer, err error)) {
+ b.RunParallel(func(pb *testing.PB) {
+ r, w, err := pipe()
+ if err != nil {
+ b.Fatal("can't get pipe:", err)
+ }
+ v := ctor()
+ enc := NewEncoder(w)
+ dec := NewDecoder(r)
+ for pb.Next() {
+ if err := enc.Encode(v); err != nil {
+ b.Fatal("encode error:", err)
+ }
+ if err := dec.Decode(v); err != nil {
+ b.Fatal("decode error:", err)
+ }
+ }
+ })
+}
+
+func BenchmarkEndToEndPipe(b *testing.B) {
+ benchmarkEndToEnd(b, func() interface{} {
+ return &Bench{7, 3.2, "now is the time", bytes.Repeat([]byte("for all good men"), 100)}
+ }, func() (r io.Reader, w io.Writer, err error) {
+ r, w, err = os.Pipe()
+ return
+ })
+}
+
+func BenchmarkEndToEndByteBuffer(b *testing.B) {
+ benchmarkEndToEnd(b, func() interface{} {
+ return &Bench{7, 3.2, "now is the time", bytes.Repeat([]byte("for all good men"), 100)}
+ }, func() (r io.Reader, w io.Writer, err error) {
+ var buf bytes.Buffer
+ return &buf, &buf, nil
+ })
+}
+
+func BenchmarkEndToEndSliceByteBuffer(b *testing.B) {
+ benchmarkEndToEnd(b, func() interface{} {
+ v := &Bench{7, 3.2, "now is the time", nil}
+ Register(v)
+ arr := make([]interface{}, 100)
+ for i := range arr {
+ arr[i] = v
+ }
+ return &arr
+ }, func() (r io.Reader, w io.Writer, err error) {
+ var buf bytes.Buffer
+ return &buf, &buf, nil
+ })
+}
+
+func TestCountEncodeMallocs(t *testing.T) {
+ if testing.Short() {
+ t.Skip("skipping malloc count in short mode")
+ }
+ if runtime.GOMAXPROCS(0) > 1 {
+ t.Skip("skipping; GOMAXPROCS>1")
+ }
+
+ const N = 1000
+
+ var buf bytes.Buffer
+ enc := NewEncoder(&buf)
+ bench := &Bench{7, 3.2, "now is the time", []byte("for all good men")}
+
+ allocs := testing.AllocsPerRun(N, func() {
+ err := enc.Encode(bench)
+ if err != nil {
+ t.Fatal("encode:", err)
+ }
+ })
+ if allocs != 0 {
+ t.Fatalf("mallocs per encode of type Bench: %v; wanted 0\n", allocs)
+ }
+}
+
+func TestCountDecodeMallocs(t *testing.T) {
+ if testing.Short() {
+ t.Skip("skipping malloc count in short mode")
+ }
+ if runtime.GOMAXPROCS(0) > 1 {
+ t.Skip("skipping; GOMAXPROCS>1")
+ }
+
+ const N = 1000
+
+ var buf bytes.Buffer
+ enc := NewEncoder(&buf)
+ bench := &Bench{7, 3.2, "now is the time", []byte("for all good men")}
+
+ // Fill the buffer with enough to decode
+ testing.AllocsPerRun(N, func() {
+ err := enc.Encode(bench)
+ if err != nil {
+ t.Fatal("encode:", err)
+ }
+ })
+
+ dec := NewDecoder(&buf)
+ allocs := testing.AllocsPerRun(N, func() {
+ *bench = Bench{}
+ err := dec.Decode(&bench)
+ if err != nil {
+ t.Fatal("decode:", err)
+ }
+ })
+ if allocs != 3 {
+ t.Fatalf("mallocs per decode of type Bench: %v; wanted 3\n", allocs)
+ }
+}
+
+func benchmarkEncodeSlice(b *testing.B, a interface{}) {
+ b.ResetTimer()
+ b.RunParallel(func(pb *testing.PB) {
+ var buf bytes.Buffer
+ enc := NewEncoder(&buf)
+
+ for pb.Next() {
+ buf.Reset()
+ err := enc.Encode(a)
+ if err != nil {
+ b.Fatal(err)
+ }
+ }
+ })
+}
+
+func BenchmarkEncodeComplex128Slice(b *testing.B) {
+ a := make([]complex128, 1000)
+ for i := range a {
+ a[i] = 1.2 + 3.4i
+ }
+ benchmarkEncodeSlice(b, a)
+}
+
+func BenchmarkEncodeFloat64Slice(b *testing.B) {
+ a := make([]float64, 1000)
+ for i := range a {
+ a[i] = 1.23e4
+ }
+ benchmarkEncodeSlice(b, a)
+}
+
+func BenchmarkEncodeInt32Slice(b *testing.B) {
+ a := make([]int32, 1000)
+ for i := range a {
+ a[i] = int32(i * 100)
+ }
+ benchmarkEncodeSlice(b, a)
+}
+
+func BenchmarkEncodeStringSlice(b *testing.B) {
+ a := make([]string, 1000)
+ for i := range a {
+ a[i] = "now is the time"
+ }
+ benchmarkEncodeSlice(b, a)
+}
+
+func BenchmarkEncodeInterfaceSlice(b *testing.B) {
+ a := make([]interface{}, 1000)
+ for i := range a {
+ a[i] = "now is the time"
+ }
+ benchmarkEncodeSlice(b, a)
+}
+
+// benchmarkBuf is a read buffer we can reset
+type benchmarkBuf struct {
+ offset int
+ data []byte
+}
+
+func (b *benchmarkBuf) Read(p []byte) (n int, err error) {
+ n = copy(p, b.data[b.offset:])
+ if n == 0 {
+ return 0, io.EOF
+ }
+ b.offset += n
+ return
+}
+
+func (b *benchmarkBuf) ReadByte() (c byte, err error) {
+ if b.offset >= len(b.data) {
+ return 0, io.EOF
+ }
+ c = b.data[b.offset]
+ b.offset++
+ return
+}
+
+func (b *benchmarkBuf) reset() {
+ b.offset = 0
+}
+
+func benchmarkDecodeSlice(b *testing.B, a interface{}) {
+ var buf bytes.Buffer
+ enc := NewEncoder(&buf)
+ err := enc.Encode(a)
+ if err != nil {
+ b.Fatal(err)
+ }
+
+ ra := reflect.ValueOf(a)
+ rt := ra.Type()
+ b.ResetTimer()
+
+ b.RunParallel(func(pb *testing.PB) {
+ // TODO(#19025): Move per-thread allocation before ResetTimer.
+ rp := reflect.New(rt)
+ rp.Elem().Set(reflect.MakeSlice(rt, ra.Len(), ra.Cap()))
+ p := rp.Interface()
+
+ bbuf := benchmarkBuf{data: buf.Bytes()}
+
+ for pb.Next() {
+ bbuf.reset()
+ dec := NewDecoder(&bbuf)
+ err := dec.Decode(p)
+ if err != nil {
+ b.Fatal(err)
+ }
+ }
+ })
+}
+
+func BenchmarkDecodeComplex128Slice(b *testing.B) {
+ a := make([]complex128, 1000)
+ for i := range a {
+ a[i] = 1.2 + 3.4i
+ }
+ benchmarkDecodeSlice(b, a)
+}
+
+func BenchmarkDecodeFloat64Slice(b *testing.B) {
+ a := make([]float64, 1000)
+ for i := range a {
+ a[i] = 1.23e4
+ }
+ benchmarkDecodeSlice(b, a)
+}
+
+func BenchmarkDecodeInt32Slice(b *testing.B) {
+ a := make([]int32, 1000)
+ for i := range a {
+ a[i] = 1234
+ }
+ benchmarkDecodeSlice(b, a)
+}
+
+func BenchmarkDecodeStringSlice(b *testing.B) {
+ a := make([]string, 1000)
+ for i := range a {
+ a[i] = "now is the time"
+ }
+ benchmarkDecodeSlice(b, a)
+}
+
+func BenchmarkDecodeInterfaceSlice(b *testing.B) {
+ a := make([]interface{}, 1000)
+ for i := range a {
+ a[i] = "now is the time"
+ }
+ benchmarkDecodeSlice(b, a)
+}
+
+func BenchmarkDecodeMap(b *testing.B) {
+ count := 1000
+ m := make(map[int]int, count)
+ for i := 0; i < count; i++ {
+ m[i] = i
+ }
+ var buf bytes.Buffer
+ enc := NewEncoder(&buf)
+ err := enc.Encode(m)
+ if err != nil {
+ b.Fatal(err)
+ }
+ bbuf := benchmarkBuf{data: buf.Bytes()}
+ b.ResetTimer()
+ for i := 0; i < b.N; i++ {
+ var rm map[int]int
+ bbuf.reset()
+ dec := NewDecoder(&bbuf)
+ err := dec.Decode(&rm)
+ if err != nil {
+ b.Fatal(i, err)
+ }
+ }
+}
diff --git a/src/encoding/gob/type.go b/src/encoding/gob/type.go
new file mode 100644
index 0000000..31c0ef7
--- /dev/null
+++ b/src/encoding/gob/type.go
@@ -0,0 +1,913 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gob
+
+import (
+ "encoding"
+ "errors"
+ "fmt"
+ "os"
+ "reflect"
+ "sync"
+ "sync/atomic"
+ "unicode"
+ "unicode/utf8"
+)
+
+// userTypeInfo stores the information associated with a type the user has handed
+// to the package. It's computed once and stored in a map keyed by reflection
+// type.
+type userTypeInfo struct {
+ user reflect.Type // the type the user handed us
+ base reflect.Type // the base type after all indirections
+ indir int // number of indirections to reach the base type
+ externalEnc int // xGob, xBinary, or xText
+ externalDec int // xGob, xBinary or xText
+ encIndir int8 // number of indirections to reach the receiver type; may be negative
+ decIndir int8 // number of indirections to reach the receiver type; may be negative
+}
+
+// externalEncoding bits
+const (
+ xGob = 1 + iota // GobEncoder or GobDecoder
+ xBinary // encoding.BinaryMarshaler or encoding.BinaryUnmarshaler
+ xText // encoding.TextMarshaler or encoding.TextUnmarshaler
+)
+
+var userTypeCache sync.Map // map[reflect.Type]*userTypeInfo
+
+// validType returns, and saves, the information associated with user-provided type rt.
+// If the user type is not valid, err will be non-nil. To be used when the error handler
+// is not set up.
+func validUserType(rt reflect.Type) (*userTypeInfo, error) {
+ if ui, ok := userTypeCache.Load(rt); ok {
+ return ui.(*userTypeInfo), nil
+ }
+
+ // Construct a new userTypeInfo and atomically add it to the userTypeCache.
+ // If we lose the race, we'll waste a little CPU and create a little garbage
+ // but return the existing value anyway.
+
+ ut := new(userTypeInfo)
+ ut.base = rt
+ ut.user = rt
+ // A type that is just a cycle of pointers (such as type T *T) cannot
+ // be represented in gobs, which need some concrete data. We use a
+ // cycle detection algorithm from Knuth, Vol 2, Section 3.1, Ex 6,
+ // pp 539-540. As we step through indirections, run another type at
+ // half speed. If they meet up, there's a cycle.
+ slowpoke := ut.base // walks half as fast as ut.base
+ for {
+ pt := ut.base
+ if pt.Kind() != reflect.Ptr {
+ break
+ }
+ ut.base = pt.Elem()
+ if ut.base == slowpoke { // ut.base lapped slowpoke
+ // recursive pointer type.
+ return nil, errors.New("can't represent recursive pointer type " + ut.base.String())
+ }
+ if ut.indir%2 == 0 {
+ slowpoke = slowpoke.Elem()
+ }
+ ut.indir++
+ }
+
+ if ok, indir := implementsInterface(ut.user, gobEncoderInterfaceType); ok {
+ ut.externalEnc, ut.encIndir = xGob, indir
+ } else if ok, indir := implementsInterface(ut.user, binaryMarshalerInterfaceType); ok {
+ ut.externalEnc, ut.encIndir = xBinary, indir
+ }
+
+ // NOTE(rsc): Would like to allow MarshalText here, but results in incompatibility
+ // with older encodings for net.IP. See golang.org/issue/6760.
+ // } else if ok, indir := implementsInterface(ut.user, textMarshalerInterfaceType); ok {
+ // ut.externalEnc, ut.encIndir = xText, indir
+ // }
+
+ if ok, indir := implementsInterface(ut.user, gobDecoderInterfaceType); ok {
+ ut.externalDec, ut.decIndir = xGob, indir
+ } else if ok, indir := implementsInterface(ut.user, binaryUnmarshalerInterfaceType); ok {
+ ut.externalDec, ut.decIndir = xBinary, indir
+ }
+
+ // See note above.
+ // } else if ok, indir := implementsInterface(ut.user, textUnmarshalerInterfaceType); ok {
+ // ut.externalDec, ut.decIndir = xText, indir
+ // }
+
+ ui, _ := userTypeCache.LoadOrStore(rt, ut)
+ return ui.(*userTypeInfo), nil
+}
+
+var (
+ gobEncoderInterfaceType = reflect.TypeOf((*GobEncoder)(nil)).Elem()
+ gobDecoderInterfaceType = reflect.TypeOf((*GobDecoder)(nil)).Elem()
+ binaryMarshalerInterfaceType = reflect.TypeOf((*encoding.BinaryMarshaler)(nil)).Elem()
+ binaryUnmarshalerInterfaceType = reflect.TypeOf((*encoding.BinaryUnmarshaler)(nil)).Elem()
+ textMarshalerInterfaceType = reflect.TypeOf((*encoding.TextMarshaler)(nil)).Elem()
+ textUnmarshalerInterfaceType = reflect.TypeOf((*encoding.TextUnmarshaler)(nil)).Elem()
+)
+
+// implementsInterface reports whether the type implements the
+// gobEncoder/gobDecoder interface.
+// It also returns the number of indirections required to get to the
+// implementation.
+func implementsInterface(typ, gobEncDecType reflect.Type) (success bool, indir int8) {
+ if typ == nil {
+ return
+ }
+ rt := typ
+ // The type might be a pointer and we need to keep
+ // dereferencing to the base type until we find an implementation.
+ for {
+ if rt.Implements(gobEncDecType) {
+ return true, indir
+ }
+ if p := rt; p.Kind() == reflect.Ptr {
+ indir++
+ if indir > 100 { // insane number of indirections
+ return false, 0
+ }
+ rt = p.Elem()
+ continue
+ }
+ break
+ }
+ // No luck yet, but if this is a base type (non-pointer), the pointer might satisfy.
+ if typ.Kind() != reflect.Ptr {
+ // Not a pointer, but does the pointer work?
+ if reflect.PtrTo(typ).Implements(gobEncDecType) {
+ return true, -1
+ }
+ }
+ return false, 0
+}
+
+// userType returns, and saves, the information associated with user-provided type rt.
+// If the user type is not valid, it calls error.
+func userType(rt reflect.Type) *userTypeInfo {
+ ut, err := validUserType(rt)
+ if err != nil {
+ error_(err)
+ }
+ return ut
+}
+
+// A typeId represents a gob Type as an integer that can be passed on the wire.
+// Internally, typeIds are used as keys to a map to recover the underlying type info.
+type typeId int32
+
+var nextId typeId // incremented for each new type we build
+var typeLock sync.Mutex // set while building a type
+const firstUserId = 64 // lowest id number granted to user
+
+type gobType interface {
+ id() typeId
+ setId(id typeId)
+ name() string
+ string() string // not public; only for debugging
+ safeString(seen map[typeId]bool) string
+}
+
+var types = make(map[reflect.Type]gobType)
+var idToType = make(map[typeId]gobType)
+var builtinIdToType map[typeId]gobType // set in init() after builtins are established
+
+func setTypeId(typ gobType) {
+ // When building recursive types, someone may get there before us.
+ if typ.id() != 0 {
+ return
+ }
+ nextId++
+ typ.setId(nextId)
+ idToType[nextId] = typ
+}
+
+func (t typeId) gobType() gobType {
+ if t == 0 {
+ return nil
+ }
+ return idToType[t]
+}
+
+// string returns the string representation of the type associated with the typeId.
+func (t typeId) string() string {
+ if t.gobType() == nil {
+ return "<nil>"
+ }
+ return t.gobType().string()
+}
+
+// Name returns the name of the type associated with the typeId.
+func (t typeId) name() string {
+ if t.gobType() == nil {
+ return "<nil>"
+ }
+ return t.gobType().name()
+}
+
+// CommonType holds elements of all types.
+// It is a historical artifact, kept for binary compatibility and exported
+// only for the benefit of the package's encoding of type descriptors. It is
+// not intended for direct use by clients.
+type CommonType struct {
+ Name string
+ Id typeId
+}
+
+func (t *CommonType) id() typeId { return t.Id }
+
+func (t *CommonType) setId(id typeId) { t.Id = id }
+
+func (t *CommonType) string() string { return t.Name }
+
+func (t *CommonType) safeString(seen map[typeId]bool) string {
+ return t.Name
+}
+
+func (t *CommonType) name() string { return t.Name }
+
+// Create and check predefined types
+// The string for tBytes is "bytes" not "[]byte" to signify its specialness.
+
+var (
+ // Primordial types, needed during initialization.
+ // Always passed as pointers so the interface{} type
+ // goes through without losing its interfaceness.
+ tBool = bootstrapType("bool", (*bool)(nil), 1)
+ tInt = bootstrapType("int", (*int)(nil), 2)
+ tUint = bootstrapType("uint", (*uint)(nil), 3)
+ tFloat = bootstrapType("float", (*float64)(nil), 4)
+ tBytes = bootstrapType("bytes", (*[]byte)(nil), 5)
+ tString = bootstrapType("string", (*string)(nil), 6)
+ tComplex = bootstrapType("complex", (*complex128)(nil), 7)
+ tInterface = bootstrapType("interface", (*interface{})(nil), 8)
+ // Reserve some Ids for compatible expansion
+ tReserved7 = bootstrapType("_reserved1", (*struct{ r7 int })(nil), 9)
+ tReserved6 = bootstrapType("_reserved1", (*struct{ r6 int })(nil), 10)
+ tReserved5 = bootstrapType("_reserved1", (*struct{ r5 int })(nil), 11)
+ tReserved4 = bootstrapType("_reserved1", (*struct{ r4 int })(nil), 12)
+ tReserved3 = bootstrapType("_reserved1", (*struct{ r3 int })(nil), 13)
+ tReserved2 = bootstrapType("_reserved1", (*struct{ r2 int })(nil), 14)
+ tReserved1 = bootstrapType("_reserved1", (*struct{ r1 int })(nil), 15)
+)
+
+// Predefined because it's needed by the Decoder
+var tWireType = mustGetTypeInfo(reflect.TypeOf(wireType{})).id
+var wireTypeUserInfo *userTypeInfo // userTypeInfo of (*wireType)
+
+func init() {
+ // Some magic numbers to make sure there are no surprises.
+ checkId(16, tWireType)
+ checkId(17, mustGetTypeInfo(reflect.TypeOf(arrayType{})).id)
+ checkId(18, mustGetTypeInfo(reflect.TypeOf(CommonType{})).id)
+ checkId(19, mustGetTypeInfo(reflect.TypeOf(sliceType{})).id)
+ checkId(20, mustGetTypeInfo(reflect.TypeOf(structType{})).id)
+ checkId(21, mustGetTypeInfo(reflect.TypeOf(fieldType{})).id)
+ checkId(23, mustGetTypeInfo(reflect.TypeOf(mapType{})).id)
+
+ builtinIdToType = make(map[typeId]gobType)
+ for k, v := range idToType {
+ builtinIdToType[k] = v
+ }
+
+ // Move the id space upwards to allow for growth in the predefined world
+ // without breaking existing files.
+ if nextId > firstUserId {
+ panic(fmt.Sprintln("nextId too large:", nextId))
+ }
+ nextId = firstUserId
+ registerBasics()
+ wireTypeUserInfo = userType(reflect.TypeOf((*wireType)(nil)))
+}
+
+// Array type
+type arrayType struct {
+ CommonType
+ Elem typeId
+ Len int
+}
+
+func newArrayType(name string) *arrayType {
+ a := &arrayType{CommonType{Name: name}, 0, 0}
+ return a
+}
+
+func (a *arrayType) init(elem gobType, len int) {
+ // Set our type id before evaluating the element's, in case it's our own.
+ setTypeId(a)
+ a.Elem = elem.id()
+ a.Len = len
+}
+
+func (a *arrayType) safeString(seen map[typeId]bool) string {
+ if seen[a.Id] {
+ return a.Name
+ }
+ seen[a.Id] = true
+ return fmt.Sprintf("[%d]%s", a.Len, a.Elem.gobType().safeString(seen))
+}
+
+func (a *arrayType) string() string { return a.safeString(make(map[typeId]bool)) }
+
+// GobEncoder type (something that implements the GobEncoder interface)
+type gobEncoderType struct {
+ CommonType
+}
+
+func newGobEncoderType(name string) *gobEncoderType {
+ g := &gobEncoderType{CommonType{Name: name}}
+ setTypeId(g)
+ return g
+}
+
+func (g *gobEncoderType) safeString(seen map[typeId]bool) string {
+ return g.Name
+}
+
+func (g *gobEncoderType) string() string { return g.Name }
+
+// Map type
+type mapType struct {
+ CommonType
+ Key typeId
+ Elem typeId
+}
+
+func newMapType(name string) *mapType {
+ m := &mapType{CommonType{Name: name}, 0, 0}
+ return m
+}
+
+func (m *mapType) init(key, elem gobType) {
+ // Set our type id before evaluating the element's, in case it's our own.
+ setTypeId(m)
+ m.Key = key.id()
+ m.Elem = elem.id()
+}
+
+func (m *mapType) safeString(seen map[typeId]bool) string {
+ if seen[m.Id] {
+ return m.Name
+ }
+ seen[m.Id] = true
+ key := m.Key.gobType().safeString(seen)
+ elem := m.Elem.gobType().safeString(seen)
+ return fmt.Sprintf("map[%s]%s", key, elem)
+}
+
+func (m *mapType) string() string { return m.safeString(make(map[typeId]bool)) }
+
+// Slice type
+type sliceType struct {
+ CommonType
+ Elem typeId
+}
+
+func newSliceType(name string) *sliceType {
+ s := &sliceType{CommonType{Name: name}, 0}
+ return s
+}
+
+func (s *sliceType) init(elem gobType) {
+ // Set our type id before evaluating the element's, in case it's our own.
+ setTypeId(s)
+ // See the comments about ids in newTypeObject. Only slices and
+ // structs have mutual recursion.
+ if elem.id() == 0 {
+ setTypeId(elem)
+ }
+ s.Elem = elem.id()
+}
+
+func (s *sliceType) safeString(seen map[typeId]bool) string {
+ if seen[s.Id] {
+ return s.Name
+ }
+ seen[s.Id] = true
+ return fmt.Sprintf("[]%s", s.Elem.gobType().safeString(seen))
+}
+
+func (s *sliceType) string() string { return s.safeString(make(map[typeId]bool)) }
+
+// Struct type
+type fieldType struct {
+ Name string
+ Id typeId
+}
+
+type structType struct {
+ CommonType
+ Field []*fieldType
+}
+
+func (s *structType) safeString(seen map[typeId]bool) string {
+ if s == nil {
+ return "<nil>"
+ }
+ if _, ok := seen[s.Id]; ok {
+ return s.Name
+ }
+ seen[s.Id] = true
+ str := s.Name + " = struct { "
+ for _, f := range s.Field {
+ str += fmt.Sprintf("%s %s; ", f.Name, f.Id.gobType().safeString(seen))
+ }
+ str += "}"
+ return str
+}
+
+func (s *structType) string() string { return s.safeString(make(map[typeId]bool)) }
+
+func newStructType(name string) *structType {
+ s := &structType{CommonType{Name: name}, nil}
+ // For historical reasons we set the id here rather than init.
+ // See the comment in newTypeObject for details.
+ setTypeId(s)
+ return s
+}
+
+// newTypeObject allocates a gobType for the reflection type rt.
+// Unless ut represents a GobEncoder, rt should be the base type
+// of ut.
+// This is only called from the encoding side. The decoding side
+// works through typeIds and userTypeInfos alone.
+func newTypeObject(name string, ut *userTypeInfo, rt reflect.Type) (gobType, error) {
+ // Does this type implement GobEncoder?
+ if ut.externalEnc != 0 {
+ return newGobEncoderType(name), nil
+ }
+ var err error
+ var type0, type1 gobType
+ defer func() {
+ if err != nil {
+ delete(types, rt)
+ }
+ }()
+ // Install the top-level type before the subtypes (e.g. struct before
+ // fields) so recursive types can be constructed safely.
+ switch t := rt; t.Kind() {
+ // All basic types are easy: they are predefined.
+ case reflect.Bool:
+ return tBool.gobType(), nil
+
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ return tInt.gobType(), nil
+
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ return tUint.gobType(), nil
+
+ case reflect.Float32, reflect.Float64:
+ return tFloat.gobType(), nil
+
+ case reflect.Complex64, reflect.Complex128:
+ return tComplex.gobType(), nil
+
+ case reflect.String:
+ return tString.gobType(), nil
+
+ case reflect.Interface:
+ return tInterface.gobType(), nil
+
+ case reflect.Array:
+ at := newArrayType(name)
+ types[rt] = at
+ type0, err = getBaseType("", t.Elem())
+ if err != nil {
+ return nil, err
+ }
+ // Historical aside:
+ // For arrays, maps, and slices, we set the type id after the elements
+ // are constructed. This is to retain the order of type id allocation after
+ // a fix made to handle recursive types, which changed the order in
+ // which types are built. Delaying the setting in this way preserves
+ // type ids while allowing recursive types to be described. Structs,
+ // done below, were already handling recursion correctly so they
+ // assign the top-level id before those of the field.
+ at.init(type0, t.Len())
+ return at, nil
+
+ case reflect.Map:
+ mt := newMapType(name)
+ types[rt] = mt
+ type0, err = getBaseType("", t.Key())
+ if err != nil {
+ return nil, err
+ }
+ type1, err = getBaseType("", t.Elem())
+ if err != nil {
+ return nil, err
+ }
+ mt.init(type0, type1)
+ return mt, nil
+
+ case reflect.Slice:
+ // []byte == []uint8 is a special case
+ if t.Elem().Kind() == reflect.Uint8 {
+ return tBytes.gobType(), nil
+ }
+ st := newSliceType(name)
+ types[rt] = st
+ type0, err = getBaseType(t.Elem().Name(), t.Elem())
+ if err != nil {
+ return nil, err
+ }
+ st.init(type0)
+ return st, nil
+
+ case reflect.Struct:
+ st := newStructType(name)
+ types[rt] = st
+ idToType[st.id()] = st
+ for i := 0; i < t.NumField(); i++ {
+ f := t.Field(i)
+ if !isSent(&f) {
+ continue
+ }
+ typ := userType(f.Type).base
+ tname := typ.Name()
+ if tname == "" {
+ t := userType(f.Type).base
+ tname = t.String()
+ }
+ gt, err := getBaseType(tname, f.Type)
+ if err != nil {
+ return nil, err
+ }
+ // Some mutually recursive types can cause us to be here while
+ // still defining the element. Fix the element type id here.
+ // We could do this more neatly by setting the id at the start of
+ // building every type, but that would break binary compatibility.
+ if gt.id() == 0 {
+ setTypeId(gt)
+ }
+ st.Field = append(st.Field, &fieldType{f.Name, gt.id()})
+ }
+ return st, nil
+
+ default:
+ return nil, errors.New("gob NewTypeObject can't handle type: " + rt.String())
+ }
+}
+
+// isExported reports whether this is an exported - upper case - name.
+func isExported(name string) bool {
+ rune, _ := utf8.DecodeRuneInString(name)
+ return unicode.IsUpper(rune)
+}
+
+// isSent reports whether this struct field is to be transmitted.
+// It will be transmitted only if it is exported and not a chan or func field
+// or pointer to chan or func.
+func isSent(field *reflect.StructField) bool {
+ if !isExported(field.Name) {
+ return false
+ }
+ // If the field is a chan or func or pointer thereto, don't send it.
+ // That is, treat it like an unexported field.
+ typ := field.Type
+ for typ.Kind() == reflect.Ptr {
+ typ = typ.Elem()
+ }
+ if typ.Kind() == reflect.Chan || typ.Kind() == reflect.Func {
+ return false
+ }
+ return true
+}
+
+// getBaseType returns the Gob type describing the given reflect.Type's base type.
+// typeLock must be held.
+func getBaseType(name string, rt reflect.Type) (gobType, error) {
+ ut := userType(rt)
+ return getType(name, ut, ut.base)
+}
+
+// getType returns the Gob type describing the given reflect.Type.
+// Should be called only when handling GobEncoders/Decoders,
+// which may be pointers. All other types are handled through the
+// base type, never a pointer.
+// typeLock must be held.
+func getType(name string, ut *userTypeInfo, rt reflect.Type) (gobType, error) {
+ typ, present := types[rt]
+ if present {
+ return typ, nil
+ }
+ typ, err := newTypeObject(name, ut, rt)
+ if err == nil {
+ types[rt] = typ
+ }
+ return typ, err
+}
+
+func checkId(want, got typeId) {
+ if want != got {
+ fmt.Fprintf(os.Stderr, "checkId: %d should be %d\n", int(got), int(want))
+ panic("bootstrap type wrong id: " + got.name() + " " + got.string() + " not " + want.string())
+ }
+}
+
+// used for building the basic types; called only from init(). the incoming
+// interface always refers to a pointer.
+func bootstrapType(name string, e interface{}, expect typeId) typeId {
+ rt := reflect.TypeOf(e).Elem()
+ _, present := types[rt]
+ if present {
+ panic("bootstrap type already present: " + name + ", " + rt.String())
+ }
+ typ := &CommonType{Name: name}
+ types[rt] = typ
+ setTypeId(typ)
+ checkId(expect, nextId)
+ userType(rt) // might as well cache it now
+ return nextId
+}
+
+// Representation of the information we send and receive about this type.
+// Each value we send is preceded by its type definition: an encoded int.
+// However, the very first time we send the value, we first send the pair
+// (-id, wireType).
+// For bootstrapping purposes, we assume that the recipient knows how
+// to decode a wireType; it is exactly the wireType struct here, interpreted
+// using the gob rules for sending a structure, except that we assume the
+// ids for wireType and structType etc. are known. The relevant pieces
+// are built in encode.go's init() function.
+// To maintain binary compatibility, if you extend this type, always put
+// the new fields last.
+type wireType struct {
+ ArrayT *arrayType
+ SliceT *sliceType
+ StructT *structType
+ MapT *mapType
+ GobEncoderT *gobEncoderType
+ BinaryMarshalerT *gobEncoderType
+ TextMarshalerT *gobEncoderType
+}
+
+func (w *wireType) string() string {
+ const unknown = "unknown type"
+ if w == nil {
+ return unknown
+ }
+ switch {
+ case w.ArrayT != nil:
+ return w.ArrayT.Name
+ case w.SliceT != nil:
+ return w.SliceT.Name
+ case w.StructT != nil:
+ return w.StructT.Name
+ case w.MapT != nil:
+ return w.MapT.Name
+ case w.GobEncoderT != nil:
+ return w.GobEncoderT.Name
+ case w.BinaryMarshalerT != nil:
+ return w.BinaryMarshalerT.Name
+ case w.TextMarshalerT != nil:
+ return w.TextMarshalerT.Name
+ }
+ return unknown
+}
+
+type typeInfo struct {
+ id typeId
+ encInit sync.Mutex // protects creation of encoder
+ encoder atomic.Value // *encEngine
+ wire *wireType
+}
+
+// typeInfoMap is an atomic pointer to map[reflect.Type]*typeInfo.
+// It's updated copy-on-write. Readers just do an atomic load
+// to get the current version of the map. Writers make a full copy of
+// the map and atomically update the pointer to point to the new map.
+// Under heavy read contention, this is significantly faster than a map
+// protected by a mutex.
+var typeInfoMap atomic.Value
+
+func lookupTypeInfo(rt reflect.Type) *typeInfo {
+ m, _ := typeInfoMap.Load().(map[reflect.Type]*typeInfo)
+ return m[rt]
+}
+
+func getTypeInfo(ut *userTypeInfo) (*typeInfo, error) {
+ rt := ut.base
+ if ut.externalEnc != 0 {
+ // We want the user type, not the base type.
+ rt = ut.user
+ }
+ if info := lookupTypeInfo(rt); info != nil {
+ return info, nil
+ }
+ return buildTypeInfo(ut, rt)
+}
+
+// buildTypeInfo constructs the type information for the type
+// and stores it in the type info map.
+func buildTypeInfo(ut *userTypeInfo, rt reflect.Type) (*typeInfo, error) {
+ typeLock.Lock()
+ defer typeLock.Unlock()
+
+ if info := lookupTypeInfo(rt); info != nil {
+ return info, nil
+ }
+
+ gt, err := getBaseType(rt.Name(), rt)
+ if err != nil {
+ return nil, err
+ }
+ info := &typeInfo{id: gt.id()}
+
+ if ut.externalEnc != 0 {
+ userType, err := getType(rt.Name(), ut, rt)
+ if err != nil {
+ return nil, err
+ }
+ gt := userType.id().gobType().(*gobEncoderType)
+ switch ut.externalEnc {
+ case xGob:
+ info.wire = &wireType{GobEncoderT: gt}
+ case xBinary:
+ info.wire = &wireType{BinaryMarshalerT: gt}
+ case xText:
+ info.wire = &wireType{TextMarshalerT: gt}
+ }
+ rt = ut.user
+ } else {
+ t := info.id.gobType()
+ switch typ := rt; typ.Kind() {
+ case reflect.Array:
+ info.wire = &wireType{ArrayT: t.(*arrayType)}
+ case reflect.Map:
+ info.wire = &wireType{MapT: t.(*mapType)}
+ case reflect.Slice:
+ // []byte == []uint8 is a special case handled separately
+ if typ.Elem().Kind() != reflect.Uint8 {
+ info.wire = &wireType{SliceT: t.(*sliceType)}
+ }
+ case reflect.Struct:
+ info.wire = &wireType{StructT: t.(*structType)}
+ }
+ }
+
+ // Create new map with old contents plus new entry.
+ newm := make(map[reflect.Type]*typeInfo)
+ m, _ := typeInfoMap.Load().(map[reflect.Type]*typeInfo)
+ for k, v := range m {
+ newm[k] = v
+ }
+ newm[rt] = info
+ typeInfoMap.Store(newm)
+ return info, nil
+}
+
+// Called only when a panic is acceptable and unexpected.
+func mustGetTypeInfo(rt reflect.Type) *typeInfo {
+ t, err := getTypeInfo(userType(rt))
+ if err != nil {
+ panic("getTypeInfo: " + err.Error())
+ }
+ return t
+}
+
+// GobEncoder is the interface describing data that provides its own
+// representation for encoding values for transmission to a GobDecoder.
+// A type that implements GobEncoder and GobDecoder has complete
+// control over the representation of its data and may therefore
+// contain things such as private fields, channels, and functions,
+// which are not usually transmissible in gob streams.
+//
+// Note: Since gobs can be stored permanently, it is good design
+// to guarantee the encoding used by a GobEncoder is stable as the
+// software evolves. For instance, it might make sense for GobEncode
+// to include a version number in the encoding.
+type GobEncoder interface {
+ // GobEncode returns a byte slice representing the encoding of the
+ // receiver for transmission to a GobDecoder, usually of the same
+ // concrete type.
+ GobEncode() ([]byte, error)
+}
+
+// GobDecoder is the interface describing data that provides its own
+// routine for decoding transmitted values sent by a GobEncoder.
+type GobDecoder interface {
+ // GobDecode overwrites the receiver, which must be a pointer,
+ // with the value represented by the byte slice, which was written
+ // by GobEncode, usually for the same concrete type.
+ GobDecode([]byte) error
+}
+
+var (
+ nameToConcreteType sync.Map // map[string]reflect.Type
+ concreteTypeToName sync.Map // map[reflect.Type]string
+)
+
+// RegisterName is like Register but uses the provided name rather than the
+// type's default.
+func RegisterName(name string, value interface{}) {
+ if name == "" {
+ // reserved for nil
+ panic("attempt to register empty name")
+ }
+
+ ut := userType(reflect.TypeOf(value))
+
+ // Check for incompatible duplicates. The name must refer to the
+ // same user type, and vice versa.
+
+ // Store the name and type provided by the user....
+ if t, dup := nameToConcreteType.LoadOrStore(name, reflect.TypeOf(value)); dup && t != ut.user {
+ panic(fmt.Sprintf("gob: registering duplicate types for %q: %s != %s", name, t, ut.user))
+ }
+
+ // but the flattened type in the type table, since that's what decode needs.
+ if n, dup := concreteTypeToName.LoadOrStore(ut.base, name); dup && n != name {
+ nameToConcreteType.Delete(name)
+ panic(fmt.Sprintf("gob: registering duplicate names for %s: %q != %q", ut.user, n, name))
+ }
+}
+
+// Register records a type, identified by a value for that type, under its
+// internal type name. That name will identify the concrete type of a value
+// sent or received as an interface variable. Only types that will be
+// transferred as implementations of interface values need to be registered.
+// Expecting to be used only during initialization, it panics if the mapping
+// between types and names is not a bijection.
+func Register(value interface{}) {
+ // Default to printed representation for unnamed types
+ rt := reflect.TypeOf(value)
+ name := rt.String()
+
+ // But for named types (or pointers to them), qualify with import path (but see inner comment).
+ // Dereference one pointer looking for a named type.
+ star := ""
+ if rt.Name() == "" {
+ if pt := rt; pt.Kind() == reflect.Ptr {
+ star = "*"
+ // NOTE: The following line should be rt = pt.Elem() to implement
+ // what the comment above claims, but fixing it would break compatibility
+ // with existing gobs.
+ //
+ // Given package p imported as "full/p" with these definitions:
+ // package p
+ // type T1 struct { ... }
+ // this table shows the intended and actual strings used by gob to
+ // name the types:
+ //
+ // Type Correct string Actual string
+ //
+ // T1 full/p.T1 full/p.T1
+ // *T1 *full/p.T1 *p.T1
+ //
+ // The missing full path cannot be fixed without breaking existing gob decoders.
+ rt = pt
+ }
+ }
+ if rt.Name() != "" {
+ if rt.PkgPath() == "" {
+ name = star + rt.Name()
+ } else {
+ name = star + rt.PkgPath() + "." + rt.Name()
+ }
+ }
+
+ RegisterName(name, value)
+}
+
+func registerBasics() {
+ Register(int(0))
+ Register(int8(0))
+ Register(int16(0))
+ Register(int32(0))
+ Register(int64(0))
+ Register(uint(0))
+ Register(uint8(0))
+ Register(uint16(0))
+ Register(uint32(0))
+ Register(uint64(0))
+ Register(float32(0))
+ Register(float64(0))
+ Register(complex64(0i))
+ Register(complex128(0i))
+ Register(uintptr(0))
+ Register(false)
+ Register("")
+ Register([]byte(nil))
+ Register([]int(nil))
+ Register([]int8(nil))
+ Register([]int16(nil))
+ Register([]int32(nil))
+ Register([]int64(nil))
+ Register([]uint(nil))
+ Register([]uint8(nil))
+ Register([]uint16(nil))
+ Register([]uint32(nil))
+ Register([]uint64(nil))
+ Register([]float32(nil))
+ Register([]float64(nil))
+ Register([]complex64(nil))
+ Register([]complex128(nil))
+ Register([]uintptr(nil))
+ Register([]bool(nil))
+ Register([]string(nil))
+}
diff --git a/src/encoding/gob/type_test.go b/src/encoding/gob/type_test.go
new file mode 100644
index 0000000..934270e
--- /dev/null
+++ b/src/encoding/gob/type_test.go
@@ -0,0 +1,262 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gob
+
+import (
+ "bytes"
+ "reflect"
+ "sync"
+ "testing"
+)
+
+type typeT struct {
+ id typeId
+ str string
+}
+
+var basicTypes = []typeT{
+ {tBool, "bool"},
+ {tInt, "int"},
+ {tUint, "uint"},
+ {tFloat, "float"},
+ {tBytes, "bytes"},
+ {tString, "string"},
+}
+
+func getTypeUnlocked(name string, rt reflect.Type) gobType {
+ typeLock.Lock()
+ defer typeLock.Unlock()
+ t, err := getBaseType(name, rt)
+ if err != nil {
+ panic("getTypeUnlocked: " + err.Error())
+ }
+ return t
+}
+
+// Sanity checks
+func TestBasic(t *testing.T) {
+ for _, tt := range basicTypes {
+ if tt.id.string() != tt.str {
+ t.Errorf("checkType: expected %q got %s", tt.str, tt.id.string())
+ }
+ if tt.id == 0 {
+ t.Errorf("id for %q is zero", tt.str)
+ }
+ }
+}
+
+// Reregister some basic types to check registration is idempotent.
+func TestReregistration(t *testing.T) {
+ newtyp := getTypeUnlocked("int", reflect.TypeOf(int(0)))
+ if newtyp != tInt.gobType() {
+ t.Errorf("reregistration of %s got new type", newtyp.string())
+ }
+ newtyp = getTypeUnlocked("uint", reflect.TypeOf(uint(0)))
+ if newtyp != tUint.gobType() {
+ t.Errorf("reregistration of %s got new type", newtyp.string())
+ }
+ newtyp = getTypeUnlocked("string", reflect.TypeOf("hello"))
+ if newtyp != tString.gobType() {
+ t.Errorf("reregistration of %s got new type", newtyp.string())
+ }
+}
+
+func TestArrayType(t *testing.T) {
+ var a3 [3]int
+ a3int := getTypeUnlocked("foo", reflect.TypeOf(a3))
+ newa3int := getTypeUnlocked("bar", reflect.TypeOf(a3))
+ if a3int != newa3int {
+ t.Errorf("second registration of [3]int creates new type")
+ }
+ var a4 [4]int
+ a4int := getTypeUnlocked("goo", reflect.TypeOf(a4))
+ if a3int == a4int {
+ t.Errorf("registration of [3]int creates same type as [4]int")
+ }
+ var b3 [3]bool
+ a3bool := getTypeUnlocked("", reflect.TypeOf(b3))
+ if a3int == a3bool {
+ t.Errorf("registration of [3]bool creates same type as [3]int")
+ }
+ str := a3bool.string()
+ expected := "[3]bool"
+ if str != expected {
+ t.Errorf("array printed as %q; expected %q", str, expected)
+ }
+}
+
+func TestSliceType(t *testing.T) {
+ var s []int
+ sint := getTypeUnlocked("slice", reflect.TypeOf(s))
+ var news []int
+ newsint := getTypeUnlocked("slice1", reflect.TypeOf(news))
+ if sint != newsint {
+ t.Errorf("second registration of []int creates new type")
+ }
+ var b []bool
+ sbool := getTypeUnlocked("", reflect.TypeOf(b))
+ if sbool == sint {
+ t.Errorf("registration of []bool creates same type as []int")
+ }
+ str := sbool.string()
+ expected := "[]bool"
+ if str != expected {
+ t.Errorf("slice printed as %q; expected %q", str, expected)
+ }
+}
+
+func TestMapType(t *testing.T) {
+ var m map[string]int
+ mapStringInt := getTypeUnlocked("map", reflect.TypeOf(m))
+ var newm map[string]int
+ newMapStringInt := getTypeUnlocked("map1", reflect.TypeOf(newm))
+ if mapStringInt != newMapStringInt {
+ t.Errorf("second registration of map[string]int creates new type")
+ }
+ var b map[string]bool
+ mapStringBool := getTypeUnlocked("", reflect.TypeOf(b))
+ if mapStringBool == mapStringInt {
+ t.Errorf("registration of map[string]bool creates same type as map[string]int")
+ }
+ str := mapStringBool.string()
+ expected := "map[string]bool"
+ if str != expected {
+ t.Errorf("map printed as %q; expected %q", str, expected)
+ }
+}
+
+type Bar struct {
+ X string
+}
+
+// This structure has pointers and refers to itself, making it a good test case.
+type Foo struct {
+ A int
+ B int32 // will become int
+ C string
+ D []byte
+ E *float64 // will become float64
+ F ****float64 // will become float64
+ G *Bar
+ H *Bar // should not interpolate the definition of Bar again
+ I *Foo // will not explode
+}
+
+func TestStructType(t *testing.T) {
+ sstruct := getTypeUnlocked("Foo", reflect.TypeOf(Foo{}))
+ str := sstruct.string()
+ // If we can print it correctly, we built it correctly.
+ expected := "Foo = struct { A int; B int; C string; D bytes; E float; F float; G Bar = struct { X string; }; H Bar; I Foo; }"
+ if str != expected {
+ t.Errorf("struct printed as %q; expected %q", str, expected)
+ }
+}
+
+// Should be OK to register the same type multiple times, as long as they're
+// at the same level of indirection.
+func TestRegistration(t *testing.T) {
+ type T struct{ a int }
+ Register(new(T))
+ Register(new(T))
+}
+
+type N1 struct{}
+type N2 struct{}
+
+// See comment in type.go/Register.
+func TestRegistrationNaming(t *testing.T) {
+ testCases := []struct {
+ t interface{}
+ name string
+ }{
+ {&N1{}, "*gob.N1"},
+ {N2{}, "encoding/gob.N2"},
+ }
+
+ for _, tc := range testCases {
+ Register(tc.t)
+
+ tct := reflect.TypeOf(tc.t)
+ ct, _ := nameToConcreteType.Load(tc.name)
+ if ct != tct {
+ t.Errorf("nameToConcreteType[%q] = %v, want %v", tc.name, ct, tct)
+ }
+ // concreteTypeToName is keyed off the base type.
+ if tct.Kind() == reflect.Ptr {
+ tct = tct.Elem()
+ }
+ if n, _ := concreteTypeToName.Load(tct); n != tc.name {
+ t.Errorf("concreteTypeToName[%v] got %v, want %v", tct, n, tc.name)
+ }
+ }
+}
+
+func TestStressParallel(t *testing.T) {
+ type T2 struct{ A int }
+ c := make(chan bool)
+ const N = 10
+ for i := 0; i < N; i++ {
+ go func() {
+ p := new(T2)
+ Register(p)
+ b := new(bytes.Buffer)
+ enc := NewEncoder(b)
+ err := enc.Encode(p)
+ if err != nil {
+ t.Error("encoder fail:", err)
+ }
+ dec := NewDecoder(b)
+ err = dec.Decode(p)
+ if err != nil {
+ t.Error("decoder fail:", err)
+ }
+ c <- true
+ }()
+ }
+ for i := 0; i < N; i++ {
+ <-c
+ }
+}
+
+// Issue 23328. Note that this test name is known to cmd/dist/test.go.
+func TestTypeRace(t *testing.T) {
+ c := make(chan bool)
+ var wg sync.WaitGroup
+ for i := 0; i < 2; i++ {
+ wg.Add(1)
+ go func(i int) {
+ defer wg.Done()
+ var buf bytes.Buffer
+ enc := NewEncoder(&buf)
+ dec := NewDecoder(&buf)
+ var x interface{}
+ switch i {
+ case 0:
+ x = &N1{}
+ case 1:
+ x = &N2{}
+ default:
+ t.Errorf("bad i %d", i)
+ return
+ }
+ m := make(map[string]string)
+ <-c
+ if err := enc.Encode(x); err != nil {
+ t.Error(err)
+ return
+ }
+ if err := enc.Encode(x); err != nil {
+ t.Error(err)
+ return
+ }
+ if err := dec.Decode(&m); err == nil {
+ t.Error("decode unexpectedly succeeded")
+ return
+ }
+ }(i)
+ }
+ close(c)
+ wg.Wait()
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-22 12:51:22 +0000