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Diffstat (limited to 'libgo/go/encoding/gob/encode.go')
-rw-r--r--libgo/go/encoding/gob/encode.go482
1 files changed, 209 insertions, 273 deletions
diff --git a/libgo/go/encoding/gob/encode.go b/libgo/go/encoding/gob/encode.go
index 7831c02d139..f66279f1413 100644
--- a/libgo/go/encoding/gob/encode.go
+++ b/libgo/go/encoding/gob/encode.go
@@ -2,17 +2,19 @@
// 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 (
- "bytes"
"encoding"
"math"
"reflect"
- "unsafe"
)
-const uint64Size = int(unsafe.Sizeof(uint64(0)))
+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
@@ -20,14 +22,46 @@ const uint64Size = int(unsafe.Sizeof(uint64(0)))
// 0 terminates the structure.
type encoderState struct {
enc *Encoder
- b *bytes.Buffer
+ 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
}
-func (enc *Encoder) newEncoderState(b *bytes.Buffer) *encoderState {
+// 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
+}
+
+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() {
+ e.data = e.data[0:0]
+}
+
+func (enc *Encoder) newEncoderState(b *encBuffer) *encoderState {
e := enc.freeList
if e == nil {
e = new(encoderState)
@@ -38,6 +72,9 @@ func (enc *Encoder) newEncoderState(b *bytes.Buffer) *encoderState {
e.sendZero = false
e.fieldnum = 0
e.b = b
+ if len(b.data) == 0 {
+ b.data = b.scratch[0:0]
+ }
return e
}
@@ -54,10 +91,7 @@ func (enc *Encoder) freeEncoderState(e *encoderState) {
// encodeUint writes an encoded unsigned integer to state.b.
func (state *encoderState) encodeUint(x uint64) {
if x <= 0x7F {
- err := state.b.WriteByte(uint8(x))
- if err != nil {
- error_(err)
- }
+ state.b.WriteByte(uint8(x))
return
}
i := uint64Size
@@ -67,10 +101,7 @@ func (state *encoderState) encodeUint(x uint64) {
i--
}
state.buf[i] = uint8(i - uint64Size) // = loop count, negated
- _, err := state.b.Write(state.buf[i : uint64Size+1])
- if err != nil {
- error_(err)
- }
+ state.b.Write(state.buf[i : uint64Size+1])
}
// encodeInt writes an encoded signed integer to state.w.
@@ -87,14 +118,14 @@ func (state *encoderState) encodeInt(i int64) {
}
// encOp is the signature of an encoding operator for a given type.
-type encOp func(i *encInstr, state *encoderState, p unsafe.Pointer)
+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
- indir int // how many pointer indirections to reach the value in the struct
- offset uintptr // offset in the structure of the field to encode
+ 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.
@@ -115,20 +146,20 @@ func (state *encoderState) update(instr *encInstr) {
// encoded integer, followed by the field data in its appropriate
// format.
-// encIndirect dereferences p indir times and returns the result.
-func encIndirect(p unsafe.Pointer, indir int) unsafe.Pointer {
+// encIndirect dereferences pv indir times and returns the result.
+func encIndirect(pv reflect.Value, indir int) reflect.Value {
for ; indir > 0; indir-- {
- p = *(*unsafe.Pointer)(p)
- if p == nil {
- return unsafe.Pointer(nil)
+ if pv.IsNil() {
+ break
}
+ pv = pv.Elem()
}
- return p
+ return pv
}
-// encBool encodes the bool with address p as an unsigned 0 or 1.
-func encBool(i *encInstr, state *encoderState, p unsafe.Pointer) {
- b := *(*bool)(p)
+// 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 {
@@ -139,102 +170,21 @@ func encBool(i *encInstr, state *encoderState, p unsafe.Pointer) {
}
}
-// encInt encodes the int with address p.
-func encInt(i *encInstr, state *encoderState, p unsafe.Pointer) {
- v := int64(*(*int)(p))
- if v != 0 || state.sendZero {
- state.update(i)
- state.encodeInt(v)
- }
-}
-
-// encUint encodes the uint with address p.
-func encUint(i *encInstr, state *encoderState, p unsafe.Pointer) {
- v := uint64(*(*uint)(p))
- if v != 0 || state.sendZero {
+// 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.encodeUint(v)
+ state.encodeInt(value)
}
}
-// encInt8 encodes the int8 with address p.
-func encInt8(i *encInstr, state *encoderState, p unsafe.Pointer) {
- v := int64(*(*int8)(p))
- if v != 0 || state.sendZero {
+// 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.encodeInt(v)
- }
-}
-
-// encUint8 encodes the uint8 with address p.
-func encUint8(i *encInstr, state *encoderState, p unsafe.Pointer) {
- v := uint64(*(*uint8)(p))
- if v != 0 || state.sendZero {
- state.update(i)
- state.encodeUint(v)
- }
-}
-
-// encInt16 encodes the int16 with address p.
-func encInt16(i *encInstr, state *encoderState, p unsafe.Pointer) {
- v := int64(*(*int16)(p))
- if v != 0 || state.sendZero {
- state.update(i)
- state.encodeInt(v)
- }
-}
-
-// encUint16 encodes the uint16 with address p.
-func encUint16(i *encInstr, state *encoderState, p unsafe.Pointer) {
- v := uint64(*(*uint16)(p))
- if v != 0 || state.sendZero {
- state.update(i)
- state.encodeUint(v)
- }
-}
-
-// encInt32 encodes the int32 with address p.
-func encInt32(i *encInstr, state *encoderState, p unsafe.Pointer) {
- v := int64(*(*int32)(p))
- if v != 0 || state.sendZero {
- state.update(i)
- state.encodeInt(v)
- }
-}
-
-// encUint encodes the uint32 with address p.
-func encUint32(i *encInstr, state *encoderState, p unsafe.Pointer) {
- v := uint64(*(*uint32)(p))
- if v != 0 || state.sendZero {
- state.update(i)
- state.encodeUint(v)
- }
-}
-
-// encInt64 encodes the int64 with address p.
-func encInt64(i *encInstr, state *encoderState, p unsafe.Pointer) {
- v := *(*int64)(p)
- if v != 0 || state.sendZero {
- state.update(i)
- state.encodeInt(v)
- }
-}
-
-// encInt64 encodes the uint64 with address p.
-func encUint64(i *encInstr, state *encoderState, p unsafe.Pointer) {
- v := *(*uint64)(p)
- if v != 0 || state.sendZero {
- state.update(i)
- state.encodeUint(v)
- }
-}
-
-// encUintptr encodes the uintptr with address p.
-func encUintptr(i *encInstr, state *encoderState, p unsafe.Pointer) {
- v := uint64(*(*uintptr)(p))
- if v != 0 || state.sendZero {
- state.update(i)
- state.encodeUint(v)
+ state.encodeUint(value)
}
}
@@ -255,42 +205,20 @@ func floatBits(f float64) uint64 {
return v
}
-// encFloat32 encodes the float32 with address p.
-func encFloat32(i *encInstr, state *encoderState, p unsafe.Pointer) {
- f := *(*float32)(p)
+// 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 {
- v := floatBits(float64(f))
+ bits := floatBits(f)
state.update(i)
- state.encodeUint(v)
+ state.encodeUint(bits)
}
}
-// encFloat64 encodes the float64 with address p.
-func encFloat64(i *encInstr, state *encoderState, p unsafe.Pointer) {
- f := *(*float64)(p)
- if f != 0 || state.sendZero {
- state.update(i)
- v := floatBits(f)
- state.encodeUint(v)
- }
-}
-
-// encComplex64 encodes the complex64 with address p.
+// encComplex encodes the complex value (complex64 complex128) referenced by v.
// Complex numbers are just a pair of floating-point numbers, real part first.
-func encComplex64(i *encInstr, state *encoderState, p unsafe.Pointer) {
- c := *(*complex64)(p)
- if c != 0+0i || state.sendZero {
- rpart := floatBits(float64(real(c)))
- ipart := floatBits(float64(imag(c)))
- state.update(i)
- state.encodeUint(rpart)
- state.encodeUint(ipart)
- }
-}
-
-// encComplex128 encodes the complex128 with address p.
-func encComplex128(i *encInstr, state *encoderState, p unsafe.Pointer) {
- c := *(*complex128)(p)
+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))
@@ -300,10 +228,10 @@ func encComplex128(i *encInstr, state *encoderState, p unsafe.Pointer) {
}
}
-// encUint8Array encodes the byte slice whose header has address p.
+// 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, p unsafe.Pointer) {
- b := *(*[]byte)(p)
+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)))
@@ -311,10 +239,10 @@ func encUint8Array(i *encInstr, state *encoderState, p unsafe.Pointer) {
}
}
-// encString encodes the string whose header has address p.
+// 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, p unsafe.Pointer) {
- s := *(*string)(p)
+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)))
@@ -324,7 +252,7 @@ func encString(i *encInstr, state *encoderState, p unsafe.Pointer) {
// encStructTerminator encodes the end of an encoded struct
// as delta field number of 0.
-func encStructTerminator(i *encInstr, state *encoderState, p unsafe.Pointer) {
+func encStructTerminator(i *encInstr, state *encoderState, v reflect.Value) {
state.encodeUint(0)
}
@@ -338,60 +266,83 @@ type encEngine struct {
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 *bytes.Buffer, engine *encEngine, basep unsafe.Pointer) {
+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]
- p := basep // offset will be zero
if instr.indir > 0 {
- if p = encIndirect(p, instr.indir); p == nil {
- return
- }
+ value = encIndirect(value, instr.indir)
+ }
+ if valid(value) {
+ instr.op(instr, state, value)
}
- instr.op(instr, state, p)
- enc.freeEncoderState(state)
}
// encodeStruct encodes a single struct value.
-func (enc *Encoder) encodeStruct(b *bytes.Buffer, engine *encEngine, basep unsafe.Pointer) {
+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]
- p := unsafe.Pointer(uintptr(basep) + instr.offset)
+ if i >= value.NumField() {
+ // encStructTerminator
+ instr.op(instr, state, reflect.Value{})
+ break
+ }
+ field := value.FieldByIndex(instr.index)
if instr.indir > 0 {
- if p = encIndirect(p, instr.indir); p == nil {
+ 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, p)
+ instr.op(instr, state, field)
}
- enc.freeEncoderState(state)
}
-// encodeArray encodes the array whose 0th element is at p.
-func (enc *Encoder) encodeArray(b *bytes.Buffer, p unsafe.Pointer, op encOp, elemWid uintptr, elemIndir int, length int) {
+// 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++ {
- elemp := p
+ elem := value.Index(i)
if elemIndir > 0 {
- up := encIndirect(elemp, elemIndir)
- if up == nil {
+ elem = encIndirect(elem, elemIndir)
+ // TODO: Is elem guaranteed valid? If so we could avoid this check.
+ if !valid(elem) {
errorf("encodeArray: nil element")
}
- elemp = up
}
- op(nil, state, elemp)
- p = unsafe.Pointer(uintptr(p) + elemWid)
+ op(nil, state, elem)
}
- enc.freeEncoderState(state)
}
// encodeReflectValue is a helper for maps. It encodes the value v.
@@ -402,13 +353,11 @@ func encodeReflectValue(state *encoderState, v reflect.Value, op encOp, indir in
if !v.IsValid() {
errorf("encodeReflectValue: nil element")
}
- op(nil, state, unsafeAddr(v))
+ op(nil, state, v)
}
// encodeMap encodes a map as unsigned count followed by key:value pairs.
-// Because map internals are not exposed, we must use reflection rather than
-// addresses.
-func (enc *Encoder) encodeMap(b *bytes.Buffer, mv reflect.Value, keyOp, elemOp encOp, keyIndir, elemIndir int) {
+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
@@ -426,7 +375,7 @@ func (enc *Encoder) encodeMap(b *bytes.Buffer, mv reflect.Value, keyOp, elemOp e
// 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 *bytes.Buffer, iv reflect.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()
@@ -450,10 +399,7 @@ func (enc *Encoder) encodeInterface(b *bytes.Buffer, iv reflect.Value) {
}
// Send the name.
state.encodeUint(uint64(len(name)))
- _, err := state.b.WriteString(name)
- if err != nil {
- error_(err)
- }
+ state.b.WriteString(name)
// Define the type id if necessary.
enc.sendTypeDescriptor(enc.writer(), state, ut)
// Send the type id.
@@ -461,7 +407,7 @@ func (enc *Encoder) encodeInterface(b *bytes.Buffer, iv reflect.Value) {
// Encode the value into a new buffer. Any nested type definitions
// should be written to b, before the encoded value.
enc.pushWriter(b)
- data := new(bytes.Buffer)
+ data := new(encBuffer)
data.Write(spaceForLength)
enc.encode(data, elem, ut)
if enc.err != nil {
@@ -470,7 +416,7 @@ func (enc *Encoder) encodeInterface(b *bytes.Buffer, iv reflect.Value) {
enc.popWriter()
enc.writeMessage(b, data)
if enc.err != nil {
- error_(err)
+ error_(enc.err)
}
enc.freeEncoderState(state)
}
@@ -512,7 +458,7 @@ func isZero(val reflect.Value) bool {
// encGobEncoder encodes a value that implements the GobEncoder interface.
// The data is sent as a byte array.
-func (enc *Encoder) encodeGobEncoder(b *bytes.Buffer, ut *userTypeInfo, v reflect.Value) {
+func (enc *Encoder) encodeGobEncoder(b *encBuffer, ut *userTypeInfo, v reflect.Value) {
// TODO: should we catch panics from the called method?
var data []byte
@@ -539,30 +485,30 @@ func (enc *Encoder) encodeGobEncoder(b *bytes.Buffer, ut *userTypeInfo, v reflec
var encOpTable = [...]encOp{
reflect.Bool: encBool,
reflect.Int: encInt,
- reflect.Int8: encInt8,
- reflect.Int16: encInt16,
- reflect.Int32: encInt32,
- reflect.Int64: encInt64,
+ reflect.Int8: encInt,
+ reflect.Int16: encInt,
+ reflect.Int32: encInt,
+ reflect.Int64: encInt,
reflect.Uint: encUint,
- reflect.Uint8: encUint8,
- reflect.Uint16: encUint16,
- reflect.Uint32: encUint32,
- reflect.Uint64: encUint64,
- reflect.Uintptr: encUintptr,
- reflect.Float32: encFloat32,
- reflect.Float64: encFloat64,
- reflect.Complex64: encComplex64,
- reflect.Complex128: encComplex128,
+ 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 (enc *Encoder) encOpFor(rt reflect.Type, inProgress map[reflect.Type]*encOp) (*encOp, int) {
+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 enc.gobEncodeOpFor(ut)
+ 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.
@@ -586,31 +532,27 @@ func (enc *Encoder) encOpFor(rt reflect.Type, inProgress map[reflect.Type]*encOp
break
}
// Slices have a header; we decode it to find the underlying array.
- elemOp, elemIndir := enc.encOpFor(t.Elem(), inProgress)
- op = func(i *encInstr, state *encoderState, p unsafe.Pointer) {
- slice := (*reflect.SliceHeader)(p)
- if !state.sendZero && slice.Len == 0 {
+ 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, unsafe.Pointer(slice.Data), *elemOp, t.Elem().Size(), elemIndir, int(slice.Len))
+ state.enc.encodeArray(state.b, slice, *elemOp, elemIndir, slice.Len(), helper)
}
case reflect.Array:
// True arrays have size in the type.
- elemOp, elemIndir := enc.encOpFor(t.Elem(), inProgress)
- op = func(i *encInstr, state *encoderState, p unsafe.Pointer) {
+ 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, p, *elemOp, t.Elem().Size(), elemIndir, t.Len())
+ state.enc.encodeArray(state.b, array, *elemOp, elemIndir, array.Len(), helper)
}
case reflect.Map:
- keyOp, keyIndir := enc.encOpFor(t.Key(), inProgress)
- elemOp, elemIndir := enc.encOpFor(t.Elem(), inProgress)
- op = func(i *encInstr, state *encoderState, p unsafe.Pointer) {
- // Maps cannot be accessed by moving addresses around the way
- // that slices etc. can. We must recover a full reflection value for
- // the iteration.
- v := reflect.NewAt(t, unsafe.Pointer(p)).Elem()
- mv := reflect.Indirect(v)
+ 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() {
@@ -621,19 +563,16 @@ func (enc *Encoder) encOpFor(rt reflect.Type, inProgress map[reflect.Type]*encOp
}
case reflect.Struct:
// Generate a closure that calls out to the engine for the nested type.
- enc.getEncEngine(userType(typ))
+ getEncEngine(userType(typ), building)
info := mustGetTypeInfo(typ)
- op = func(i *encInstr, state *encoderState, p unsafe.Pointer) {
+ op = func(i *encInstr, state *encoderState, sv reflect.Value) {
state.update(i)
// indirect through info to delay evaluation for recursive structs
- state.enc.encodeStruct(state.b, info.encoder, p)
+ enc := info.encoder.Load().(*encEngine)
+ state.enc.encodeStruct(state.b, enc, sv)
}
case reflect.Interface:
- op = func(i *encInstr, state *encoderState, p unsafe.Pointer) {
- // Interfaces transmit the name and contents of the concrete
- // value they contain.
- v := reflect.NewAt(t, unsafe.Pointer(p)).Elem()
- iv := reflect.Indirect(v)
+ op = func(i *encInstr, state *encoderState, iv reflect.Value) {
if !state.sendZero && (!iv.IsValid() || iv.IsNil()) {
return
}
@@ -648,9 +587,8 @@ func (enc *Encoder) encOpFor(rt reflect.Type, inProgress map[reflect.Type]*encOp
return &op, indir
}
-// gobEncodeOpFor returns the op for a type that is known to implement
-// GobEncoder.
-func (enc *Encoder) gobEncodeOpFor(ut *userTypeInfo) (*encOp, int) {
+// 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)
@@ -660,13 +598,13 @@ func (enc *Encoder) gobEncodeOpFor(ut *userTypeInfo) (*encOp, int) {
}
}
var op encOp
- op = func(i *encInstr, state *encoderState, p unsafe.Pointer) {
- var v reflect.Value
+ op = func(i *encInstr, state *encoderState, v reflect.Value) {
if ut.encIndir == -1 {
// Need to climb up one level to turn value into pointer.
- v = reflect.NewAt(rt, unsafe.Pointer(&p)).Elem()
- } else {
- v = reflect.NewAt(rt, p).Elem()
+ if !v.CanAddr() {
+ errorf("unaddressable value of type %s", rt)
+ }
+ v = v.Addr()
}
if !state.sendZero && isZero(v) {
return
@@ -678,7 +616,7 @@ func (enc *Encoder) gobEncodeOpFor(ut *userTypeInfo) (*encOp, int) {
}
// compileEnc returns the engine to compile the type.
-func (enc *Encoder) compileEnc(ut *userTypeInfo) *encEngine {
+func compileEnc(ut *userTypeInfo, building map[*typeInfo]bool) *encEngine {
srt := ut.base
engine := new(encEngine)
seen := make(map[reflect.Type]*encOp)
@@ -692,59 +630,57 @@ func (enc *Encoder) compileEnc(ut *userTypeInfo) *encEngine {
if !isSent(&f) {
continue
}
- op, indir := enc.encOpFor(f.Type, seen)
- engine.instr = append(engine.instr, encInstr{*op, wireFieldNum, indir, uintptr(f.Offset)})
+ 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, 0, 0})
+ engine.instr = append(engine.instr, encInstr{encStructTerminator, 0, nil, 0})
} else {
engine.instr = make([]encInstr, 1)
- op, indir := enc.encOpFor(rt, seen)
- engine.instr[0] = encInstr{*op, singletonField, indir, 0} // offset is zero
+ op, indir := encOpFor(rt, seen, building)
+ engine.instr[0] = encInstr{*op, singletonField, nil, indir}
}
return engine
}
// getEncEngine returns the engine to compile the type.
-// typeLock must be held (or we're in initialization and guaranteed single-threaded).
-func (enc *Encoder) getEncEngine(ut *userTypeInfo) *encEngine {
- info, err1 := getTypeInfo(ut)
- if err1 != nil {
- error_(err1)
- }
- if info.encoder == nil {
- // Assign the encEngine now, so recursive types work correctly. But...
- info.encoder = new(encEngine)
- // ... if we fail to complete building the engine, don't cache the half-built machine.
- // Doing this here means we won't cache a type that is itself OK but
- // that contains a nested type that won't compile. The result is consistent
- // error behavior when Encode is called multiple times on the top-level type.
- ok := false
- defer func() {
- if !ok {
- info.encoder = nil
- }
- }()
- info.encoder = enc.compileEnc(ut)
- ok = true
+func getEncEngine(ut *userTypeInfo, building map[*typeInfo]bool) *encEngine {
+ info, err := getTypeInfo(ut)
+ if err != nil {
+ error_(err)
}
- return info.encoder
+ enc, ok := info.encoder.Load().(*encEngine)
+ if !ok {
+ enc = buildEncEngine(info, ut, building)
+ }
+ return enc
}
-// lockAndGetEncEngine is a function that locks and compiles.
-// This lets us hold the lock only while compiling, not when encoding.
-func (enc *Encoder) lockAndGetEncEngine(ut *userTypeInfo) *encEngine {
- typeLock.Lock()
- defer typeLock.Unlock()
- return enc.getEncEngine(ut)
+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 *bytes.Buffer, value reflect.Value, ut *userTypeInfo) {
+func (enc *Encoder) encode(b *encBuffer, value reflect.Value, ut *userTypeInfo) {
defer catchError(&enc.err)
- engine := enc.lockAndGetEncEngine(ut)
+ engine := getEncEngine(ut, nil)
indir := ut.indir
if ut.externalEnc != 0 {
indir = int(ut.encIndir)
@@ -753,8 +689,8 @@ func (enc *Encoder) encode(b *bytes.Buffer, value reflect.Value, ut *userTypeInf
value = reflect.Indirect(value)
}
if ut.externalEnc == 0 && value.Type().Kind() == reflect.Struct {
- enc.encodeStruct(b, engine, unsafeAddr(value))
+ enc.encodeStruct(b, engine, value)
} else {
- enc.encodeSingle(b, engine, unsafeAddr(value))
+ enc.encodeSingle(b, engine, value)
}
}
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