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path: root/src/pkg/gob/decode.go
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Diffstat (limited to 'src/pkg/gob/decode.go')
-rw-r--r--src/pkg/gob/decode.go488
1 files changed, 272 insertions, 216 deletions
diff --git a/src/pkg/gob/decode.go b/src/pkg/gob/decode.go
index a70799e9a..f88ca72da 100644
--- a/src/pkg/gob/decode.go
+++ b/src/pkg/gob/decode.go
@@ -13,7 +13,9 @@ import (
"math"
"os"
"reflect"
+ "unicode"
"unsafe"
+ "utf8"
)
var (
@@ -22,16 +24,20 @@ var (
errRange = os.ErrorString("gob: internal error: field numbers out of bounds")
)
-// The global execution state of an instance of the decoder.
+// The execution state of an instance of the decoder. A new state
+// is created for nested objects.
type decodeState struct {
- b *bytes.Buffer
- err os.Error
+ 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 **bytes.Buffer
fieldnum int // the last field number read.
buf []byte
}
-func newDecodeState(b *bytes.Buffer) *decodeState {
+func newDecodeState(dec *Decoder, b **bytes.Buffer) *decodeState {
d := new(decodeState)
+ d.dec = dec
d.b = b
d.buf = make([]byte, uint64Size)
return d
@@ -74,24 +80,23 @@ func decodeUintReader(r io.Reader, buf []byte) (x uint64, err os.Error) {
}
// decodeUint reads an encoded unsigned integer from state.r.
-// Sets state.err. If state.err is already non-nil, it does nothing.
// Does not check for overflow.
-func decodeUint(state *decodeState) (x uint64) {
- if state.err != nil {
- return
+func (state *decodeState) decodeUint() (x uint64) {
+ b, err := state.b.ReadByte()
+ if err != nil {
+ error(err)
}
- var b uint8
- b, state.err = state.b.ReadByte()
- if b <= 0x7f { // includes state.err != nil
+ if b <= 0x7f {
return uint64(b)
}
nb := -int(int8(b))
if nb > uint64Size {
- state.err = errBadUint
- return
+ error(errBadUint)
+ }
+ n, err := state.b.Read(state.buf[0:nb])
+ if err != nil {
+ error(err)
}
- var n int
- n, state.err = state.b.Read(state.buf[0:nb])
// 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 i := 0; i < n; i++ {
@@ -102,13 +107,9 @@ func decodeUint(state *decodeState) (x uint64) {
}
// decodeInt reads an encoded signed integer from state.r.
-// Sets state.err. If state.err is already non-nil, it does nothing.
// Does not check for overflow.
-func decodeInt(state *decodeState) int64 {
- x := decodeUint(state)
- if state.err != nil {
- return 0
- }
+func (state *decodeState) decodeInt() int64 {
+ x := state.decodeUint()
if x&1 != 0 {
return ^int64(x >> 1)
}
@@ -146,12 +147,12 @@ func decIndirect(p unsafe.Pointer, indir int) unsafe.Pointer {
}
func ignoreUint(i *decInstr, state *decodeState, p unsafe.Pointer) {
- decodeUint(state)
+ state.decodeUint()
}
func ignoreTwoUints(i *decInstr, state *decodeState, p unsafe.Pointer) {
- decodeUint(state)
- decodeUint(state)
+ state.decodeUint()
+ state.decodeUint()
}
func decBool(i *decInstr, state *decodeState, p unsafe.Pointer) {
@@ -161,7 +162,7 @@ func decBool(i *decInstr, state *decodeState, p unsafe.Pointer) {
}
p = *(*unsafe.Pointer)(p)
}
- *(*bool)(p) = decodeInt(state) != 0
+ *(*bool)(p) = state.decodeInt() != 0
}
func decInt8(i *decInstr, state *decodeState, p unsafe.Pointer) {
@@ -171,9 +172,9 @@ func decInt8(i *decInstr, state *decodeState, p unsafe.Pointer) {
}
p = *(*unsafe.Pointer)(p)
}
- v := decodeInt(state)
+ v := state.decodeInt()
if v < math.MinInt8 || math.MaxInt8 < v {
- state.err = i.ovfl
+ error(i.ovfl)
} else {
*(*int8)(p) = int8(v)
}
@@ -186,9 +187,9 @@ func decUint8(i *decInstr, state *decodeState, p unsafe.Pointer) {
}
p = *(*unsafe.Pointer)(p)
}
- v := decodeUint(state)
+ v := state.decodeUint()
if math.MaxUint8 < v {
- state.err = i.ovfl
+ error(i.ovfl)
} else {
*(*uint8)(p) = uint8(v)
}
@@ -201,9 +202,9 @@ func decInt16(i *decInstr, state *decodeState, p unsafe.Pointer) {
}
p = *(*unsafe.Pointer)(p)
}
- v := decodeInt(state)
+ v := state.decodeInt()
if v < math.MinInt16 || math.MaxInt16 < v {
- state.err = i.ovfl
+ error(i.ovfl)
} else {
*(*int16)(p) = int16(v)
}
@@ -216,9 +217,9 @@ func decUint16(i *decInstr, state *decodeState, p unsafe.Pointer) {
}
p = *(*unsafe.Pointer)(p)
}
- v := decodeUint(state)
+ v := state.decodeUint()
if math.MaxUint16 < v {
- state.err = i.ovfl
+ error(i.ovfl)
} else {
*(*uint16)(p) = uint16(v)
}
@@ -231,9 +232,9 @@ func decInt32(i *decInstr, state *decodeState, p unsafe.Pointer) {
}
p = *(*unsafe.Pointer)(p)
}
- v := decodeInt(state)
+ v := state.decodeInt()
if v < math.MinInt32 || math.MaxInt32 < v {
- state.err = i.ovfl
+ error(i.ovfl)
} else {
*(*int32)(p) = int32(v)
}
@@ -246,9 +247,9 @@ func decUint32(i *decInstr, state *decodeState, p unsafe.Pointer) {
}
p = *(*unsafe.Pointer)(p)
}
- v := decodeUint(state)
+ v := state.decodeUint()
if math.MaxUint32 < v {
- state.err = i.ovfl
+ error(i.ovfl)
} else {
*(*uint32)(p) = uint32(v)
}
@@ -261,7 +262,7 @@ func decInt64(i *decInstr, state *decodeState, p unsafe.Pointer) {
}
p = *(*unsafe.Pointer)(p)
}
- *(*int64)(p) = int64(decodeInt(state))
+ *(*int64)(p) = int64(state.decodeInt())
}
func decUint64(i *decInstr, state *decodeState, p unsafe.Pointer) {
@@ -271,7 +272,7 @@ func decUint64(i *decInstr, state *decodeState, p unsafe.Pointer) {
}
p = *(*unsafe.Pointer)(p)
}
- *(*uint64)(p) = uint64(decodeUint(state))
+ *(*uint64)(p) = uint64(state.decodeUint())
}
// Floating-point numbers are transmitted as uint64s holding the bits
@@ -290,14 +291,14 @@ func floatFromBits(u uint64) float64 {
}
func storeFloat32(i *decInstr, state *decodeState, p unsafe.Pointer) {
- v := floatFromBits(decodeUint(state))
+ v := floatFromBits(state.decodeUint())
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 {
- state.err = i.ovfl
+ error(i.ovfl)
} else {
*(*float32)(p) = float32(v)
}
@@ -320,7 +321,7 @@ func decFloat64(i *decInstr, state *decodeState, p unsafe.Pointer) {
}
p = *(*unsafe.Pointer)(p)
}
- *(*float64)(p) = floatFromBits(uint64(decodeUint(state)))
+ *(*float64)(p) = floatFromBits(uint64(state.decodeUint()))
}
// Complex numbers are just a pair of floating-point numbers, real part first.
@@ -342,8 +343,8 @@ func decComplex128(i *decInstr, state *decodeState, p unsafe.Pointer) {
}
p = *(*unsafe.Pointer)(p)
}
- real := floatFromBits(uint64(decodeUint(state)))
- imag := floatFromBits(uint64(decodeUint(state)))
+ real := floatFromBits(uint64(state.decodeUint()))
+ imag := floatFromBits(uint64(state.decodeUint()))
*(*complex128)(p) = cmplx(real, imag)
}
@@ -355,7 +356,7 @@ func decUint8Array(i *decInstr, state *decodeState, p unsafe.Pointer) {
}
p = *(*unsafe.Pointer)(p)
}
- b := make([]uint8, decodeUint(state))
+ b := make([]uint8, state.decodeUint())
state.b.Read(b)
*(*[]uint8)(p) = b
}
@@ -368,13 +369,13 @@ func decString(i *decInstr, state *decodeState, p unsafe.Pointer) {
}
p = *(*unsafe.Pointer)(p)
}
- b := make([]byte, decodeUint(state))
+ b := make([]byte, state.decodeUint())
state.b.Read(b)
*(*string)(p) = string(b)
}
func ignoreUint8Array(i *decInstr, state *decodeState, p unsafe.Pointer) {
- b := make([]byte, decodeUint(state))
+ b := make([]byte, state.decodeUint())
state.b.Read(b)
}
@@ -404,15 +405,15 @@ func allocate(rtyp reflect.Type, p uintptr, indir int) uintptr {
return *(*uintptr)(up)
}
-func decodeSingle(engine *decEngine, rtyp reflect.Type, b *bytes.Buffer, p uintptr, indir int) os.Error {
+func (dec *Decoder) decodeSingle(engine *decEngine, rtyp reflect.Type, b **bytes.Buffer, p uintptr, indir int) (err os.Error) {
+ defer catchError(&err)
p = allocate(rtyp, p, indir)
- state := newDecodeState(b)
+ state := newDecodeState(dec, b)
state.fieldnum = singletonField
basep := p
- delta := int(decodeUint(state))
+ delta := int(state.decodeUint())
if delta != 0 {
- state.err = os.ErrorString("gob decode: corrupted data: non-zero delta for singleton")
- return state.err
+ errorf("gob decode: corrupted data: non-zero delta for singleton")
}
instr := &engine.instr[singletonField]
ptr := unsafe.Pointer(basep) // offset will be zero
@@ -420,26 +421,26 @@ func decodeSingle(engine *decEngine, rtyp reflect.Type, b *bytes.Buffer, p uintp
ptr = decIndirect(ptr, instr.indir)
}
instr.op(instr, state, ptr)
- return state.err
+ return nil
}
-func decodeStruct(engine *decEngine, rtyp *reflect.StructType, b *bytes.Buffer, p uintptr, indir int) os.Error {
+func (dec *Decoder) decodeStruct(engine *decEngine, rtyp *reflect.StructType, b **bytes.Buffer, p uintptr, indir int) (err os.Error) {
+ defer catchError(&err)
p = allocate(rtyp, p, indir)
- state := newDecodeState(b)
+ state := newDecodeState(dec, b)
state.fieldnum = -1
basep := p
- for state.err == nil {
- delta := int(decodeUint(state))
+ for state.b.Len() > 0 {
+ delta := int(state.decodeUint())
if delta < 0 {
- state.err = os.ErrorString("gob decode: corrupted data: negative delta")
- break
+ errorf("gob decode: corrupted data: negative delta")
}
- if state.err != nil || delta == 0 { // struct terminator is zero delta fieldnum
+ if delta == 0 { // struct terminator is zero delta fieldnum
break
}
fieldnum := state.fieldnum + delta
if fieldnum >= len(engine.instr) {
- state.err = errRange
+ error(errRange)
break
}
instr := &engine.instr[fieldnum]
@@ -450,36 +451,35 @@ func decodeStruct(engine *decEngine, rtyp *reflect.StructType, b *bytes.Buffer,
instr.op(instr, state, p)
state.fieldnum = fieldnum
}
- return state.err
+ return nil
}
-func ignoreStruct(engine *decEngine, b *bytes.Buffer) os.Error {
- state := newDecodeState(b)
+func (dec *Decoder) ignoreStruct(engine *decEngine, b **bytes.Buffer) (err os.Error) {
+ defer catchError(&err)
+ state := newDecodeState(dec, b)
state.fieldnum = -1
- for state.err == nil {
- delta := int(decodeUint(state))
+ for state.b.Len() > 0 {
+ delta := int(state.decodeUint())
if delta < 0 {
- state.err = os.ErrorString("gob ignore decode: corrupted data: negative delta")
- break
+ errorf("gob ignore decode: corrupted data: negative delta")
}
- if state.err != nil || delta == 0 { // struct terminator is zero delta fieldnum
+ if delta == 0 { // struct terminator is zero delta fieldnum
break
}
fieldnum := state.fieldnum + delta
if fieldnum >= len(engine.instr) {
- state.err = errRange
- break
+ error(errRange)
}
instr := &engine.instr[fieldnum]
instr.op(instr, state, unsafe.Pointer(nil))
state.fieldnum = fieldnum
}
- return state.err
+ return nil
}
-func decodeArrayHelper(state *decodeState, p uintptr, elemOp decOp, elemWid uintptr, length, elemIndir int, ovfl os.ErrorString) os.Error {
+func (dec *Decoder) decodeArrayHelper(state *decodeState, p uintptr, elemOp decOp, elemWid uintptr, length, elemIndir int, ovfl os.ErrorString) {
instr := &decInstr{elemOp, 0, elemIndir, 0, ovfl}
- for i := 0; i < length && state.err == nil; i++ {
+ for i := 0; i < length; i++ {
up := unsafe.Pointer(p)
if elemIndir > 1 {
up = decIndirect(up, elemIndir)
@@ -487,17 +487,16 @@ func decodeArrayHelper(state *decodeState, p uintptr, elemOp decOp, elemWid uint
elemOp(instr, state, up)
p += uintptr(elemWid)
}
- return state.err
}
-func decodeArray(atyp *reflect.ArrayType, state *decodeState, p uintptr, elemOp decOp, elemWid uintptr, length, indir, elemIndir int, ovfl os.ErrorString) os.Error {
+func (dec *Decoder) decodeArray(atyp *reflect.ArrayType, state *decodeState, p uintptr, elemOp decOp, elemWid uintptr, length, indir, elemIndir int, ovfl os.ErrorString) {
if indir > 0 {
p = allocate(atyp, p, 1) // All but the last level has been allocated by dec.Indirect
}
- if n := decodeUint(state); n != uint64(length) {
- return os.ErrorString("gob: length mismatch in decodeArray")
+ if n := state.decodeUint(); n != uint64(length) {
+ errorf("gob: length mismatch in decodeArray")
}
- return decodeArrayHelper(state, p, elemOp, elemWid, length, elemIndir, ovfl)
+ dec.decodeArrayHelper(state, p, elemOp, elemWid, length, elemIndir, ovfl)
}
func decodeIntoValue(state *decodeState, op decOp, indir int, v reflect.Value, ovfl os.ErrorString) reflect.Value {
@@ -510,7 +509,7 @@ func decodeIntoValue(state *decodeState, op decOp, indir int, v reflect.Value, o
return v
}
-func decodeMap(mtyp *reflect.MapType, state *decodeState, p uintptr, keyOp, elemOp decOp, indir, keyIndir, elemIndir int, ovfl os.ErrorString) os.Error {
+func (dec *Decoder) decodeMap(mtyp *reflect.MapType, state *decodeState, p uintptr, keyOp, elemOp decOp, indir, keyIndir, elemIndir int, ovfl os.ErrorString) {
if indir > 0 {
p = allocate(mtyp, p, 1) // All but the last level has been allocated by dec.Indirect
}
@@ -523,50 +522,40 @@ func decodeMap(mtyp *reflect.MapType, state *decodeState, p uintptr, keyOp, elem
// that slices etc. can. We must recover a full reflection value for
// the iteration.
v := reflect.NewValue(unsafe.Unreflect(mtyp, unsafe.Pointer((p)))).(*reflect.MapValue)
- n := int(decodeUint(state))
- for i := 0; i < n && state.err == nil; i++ {
+ n := int(state.decodeUint())
+ for i := 0; i < n; i++ {
key := decodeIntoValue(state, keyOp, keyIndir, reflect.MakeZero(mtyp.Key()), ovfl)
- if state.err != nil {
- break
- }
elem := decodeIntoValue(state, elemOp, elemIndir, reflect.MakeZero(mtyp.Elem()), ovfl)
- if state.err != nil {
- break
- }
v.SetElem(key, elem)
}
- return state.err
}
-func ignoreArrayHelper(state *decodeState, elemOp decOp, length int) os.Error {
+func (dec *Decoder) ignoreArrayHelper(state *decodeState, elemOp decOp, length int) {
instr := &decInstr{elemOp, 0, 0, 0, os.ErrorString("no error")}
- for i := 0; i < length && state.err == nil; i++ {
+ for i := 0; i < length; i++ {
elemOp(instr, state, nil)
}
- return state.err
}
-func ignoreArray(state *decodeState, elemOp decOp, length int) os.Error {
- if n := decodeUint(state); n != uint64(length) {
- return os.ErrorString("gob: length mismatch in ignoreArray")
+func (dec *Decoder) ignoreArray(state *decodeState, elemOp decOp, length int) {
+ if n := state.decodeUint(); n != uint64(length) {
+ errorf("gob: length mismatch in ignoreArray")
}
- return ignoreArrayHelper(state, elemOp, length)
+ dec.ignoreArrayHelper(state, elemOp, length)
}
-func ignoreMap(state *decodeState, keyOp, elemOp decOp) os.Error {
- n := int(decodeUint(state))
+func (dec *Decoder) ignoreMap(state *decodeState, keyOp, elemOp decOp) {
+ n := int(state.decodeUint())
keyInstr := &decInstr{keyOp, 0, 0, 0, os.ErrorString("no error")}
elemInstr := &decInstr{elemOp, 0, 0, 0, os.ErrorString("no error")}
- for i := 0; i < n && state.err == nil; i++ {
+ for i := 0; i < n; i++ {
keyOp(keyInstr, state, nil)
elemOp(elemInstr, state, nil)
}
- return state.err
}
-
-func decodeSlice(atyp *reflect.SliceType, state *decodeState, p uintptr, elemOp decOp, elemWid uintptr, indir, elemIndir int, ovfl os.ErrorString) os.Error {
- n := int(uintptr(decodeUint(state)))
+func (dec *Decoder) decodeSlice(atyp *reflect.SliceType, state *decodeState, p uintptr, elemOp decOp, elemWid uintptr, indir, elemIndir int, ovfl os.ErrorString) {
+ n := int(uintptr(state.decodeUint()))
if indir > 0 {
up := unsafe.Pointer(p)
if *(*unsafe.Pointer)(up) == nil {
@@ -581,11 +570,77 @@ func decodeSlice(atyp *reflect.SliceType, state *decodeState, p uintptr, elemOp
hdrp.Data = uintptr(unsafe.NewArray(atyp.Elem(), n))
hdrp.Len = n
hdrp.Cap = n
- return decodeArrayHelper(state, hdrp.Data, elemOp, elemWid, n, elemIndir, ovfl)
+ dec.decodeArrayHelper(state, hdrp.Data, elemOp, elemWid, n, elemIndir, ovfl)
}
-func ignoreSlice(state *decodeState, elemOp decOp) os.Error {
- return ignoreArrayHelper(state, elemOp, int(decodeUint(state)))
+func (dec *Decoder) ignoreSlice(state *decodeState, elemOp decOp) {
+ dec.ignoreArrayHelper(state, elemOp, int(state.decodeUint()))
+}
+
+// setInterfaceValue sets an interface value to a concrete value through
+// reflection. If the concrete value does not implement the interface, the
+// setting will panic. This routine turns the panic into an error return.
+// This dance avoids manually checking that the value satisfies the
+// interface.
+// TODO(rsc): avoid panic+recover after fixing issue 327.
+func setInterfaceValue(ivalue *reflect.InterfaceValue, value reflect.Value) {
+ defer func() {
+ if e := recover(); e != nil {
+ error(e.(os.Error))
+ }
+ }()
+ ivalue.Set(value)
+}
+
+// decodeInterface receives the name of a concrete type followed by its value.
+// If the name is empty, the value is nil and no value is sent.
+func (dec *Decoder) decodeInterface(ityp *reflect.InterfaceType, state *decodeState, p uintptr, indir int) {
+ // Create an interface reflect.Value. We need one even for the nil case.
+ ivalue := reflect.MakeZero(ityp).(*reflect.InterfaceValue)
+ // Read the name of the concrete type.
+ b := make([]byte, state.decodeUint())
+ state.b.Read(b)
+ name := string(b)
+ if name == "" {
+ // Copy the representation of the nil interface value to the target.
+ // This is horribly unsafe and special.
+ *(*[2]uintptr)(unsafe.Pointer(p)) = ivalue.Get()
+ return
+ }
+ // The concrete type must be registered.
+ typ, ok := nameToConcreteType[name]
+ if !ok {
+ errorf("gob: name not registered for interface: %q", name)
+ }
+ // Read the concrete value.
+ value := reflect.MakeZero(typ)
+ dec.decodeValueFromBuffer(value, false, true)
+ if dec.err != nil {
+ error(dec.err)
+ }
+ // Allocate the destination interface value.
+ if indir > 0 {
+ p = allocate(ityp, p, 1) // All but the last level has been allocated by dec.Indirect
+ }
+ // Assign the concrete value to the interface.
+ // Tread carefully; it might not satisfy the interface.
+ setInterfaceValue(ivalue, value)
+ // Copy the representation of the interface value to the target.
+ // This is horribly unsafe and special.
+ *(*[2]uintptr)(unsafe.Pointer(p)) = ivalue.Get()
+}
+
+func (dec *Decoder) ignoreInterface(state *decodeState) {
+ // Read the name of the concrete type.
+ b := make([]byte, state.decodeUint())
+ _, err := state.b.Read(b)
+ if err != nil {
+ error(err)
+ }
+ dec.decodeValueFromBuffer(nil, true, true)
+ if dec.err != nil {
+ error(err)
+ }
}
// Index by Go types.
@@ -608,17 +663,18 @@ var decOpMap = []decOp{
// 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,
+ tBool: ignoreUint,
+ tInt: ignoreUint,
+ tUint: ignoreUint,
+ tFloat: ignoreUint,
+ tBytes: ignoreUint8Array,
+ tString: ignoreUint8Array,
+ tComplex: ignoreTwoUints,
}
// Return 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) (decOp, int, os.Error) {
+func (dec *Decoder) decOpFor(wireId typeId, rt reflect.Type, name string) (decOp, int) {
typ, indir := indirect(rt)
var op decOp
k := typ.Kind()
@@ -630,32 +686,23 @@ func (dec *Decoder) decOpFor(wireId typeId, rt reflect.Type, name string) (decOp
switch t := typ.(type) {
case *reflect.ArrayType:
name = "element of " + name
- elemId := dec.wireType[wireId].arrayT.Elem
- elemOp, elemIndir, err := dec.decOpFor(elemId, t.Elem(), name)
- if err != nil {
- return nil, 0, err
- }
+ elemId := dec.wireType[wireId].ArrayT.Elem
+ elemOp, elemIndir := dec.decOpFor(elemId, t.Elem(), name)
ovfl := overflow(name)
op = func(i *decInstr, state *decodeState, p unsafe.Pointer) {
- state.err = decodeArray(t, state, uintptr(p), elemOp, t.Elem().Size(), t.Len(), i.indir, elemIndir, ovfl)
+ state.dec.decodeArray(t, state, uintptr(p), elemOp, t.Elem().Size(), t.Len(), i.indir, elemIndir, ovfl)
}
case *reflect.MapType:
name = "element of " + name
- keyId := dec.wireType[wireId].mapT.Key
- elemId := dec.wireType[wireId].mapT.Elem
- keyOp, keyIndir, err := dec.decOpFor(keyId, t.Key(), name)
- if err != nil {
- return nil, 0, err
- }
- elemOp, elemIndir, err := dec.decOpFor(elemId, t.Elem(), name)
- if err != nil {
- return nil, 0, err
- }
+ keyId := dec.wireType[wireId].MapT.Key
+ elemId := dec.wireType[wireId].MapT.Elem
+ keyOp, keyIndir := dec.decOpFor(keyId, t.Key(), name)
+ elemOp, elemIndir := dec.decOpFor(elemId, t.Elem(), name)
ovfl := overflow(name)
op = func(i *decInstr, state *decodeState, p unsafe.Pointer) {
up := unsafe.Pointer(p)
- state.err = decodeMap(t, state, uintptr(up), keyOp, elemOp, i.indir, keyIndir, elemIndir, ovfl)
+ state.dec.decodeMap(t, state, uintptr(up), keyOp, elemOp, i.indir, keyIndir, elemIndir, ovfl)
}
case *reflect.SliceType:
@@ -668,111 +715,105 @@ func (dec *Decoder) decOpFor(wireId typeId, rt reflect.Type, name string) (decOp
if tt, ok := builtinIdToType[wireId]; ok {
elemId = tt.(*sliceType).Elem
} else {
- elemId = dec.wireType[wireId].sliceT.Elem
- }
- elemOp, elemIndir, err := dec.decOpFor(elemId, t.Elem(), name)
- if err != nil {
- return nil, 0, err
+ elemId = dec.wireType[wireId].SliceT.Elem
}
+ elemOp, elemIndir := dec.decOpFor(elemId, t.Elem(), name)
ovfl := overflow(name)
op = func(i *decInstr, state *decodeState, p unsafe.Pointer) {
- state.err = decodeSlice(t, state, uintptr(p), elemOp, t.Elem().Size(), i.indir, elemIndir, ovfl)
+ state.dec.decodeSlice(t, state, uintptr(p), elemOp, t.Elem().Size(), i.indir, elemIndir, ovfl)
}
case *reflect.StructType:
// Generate a closure that calls out to the engine for the nested type.
enginePtr, err := dec.getDecEnginePtr(wireId, typ)
if err != nil {
- return nil, 0, err
+ error(err)
}
op = func(i *decInstr, state *decodeState, p unsafe.Pointer) {
// indirect through enginePtr to delay evaluation for recursive structs
- state.err = decodeStruct(*enginePtr, t, state.b, uintptr(p), i.indir)
+ err = dec.decodeStruct(*enginePtr, t, state.b, uintptr(p), i.indir)
+ if err != nil {
+ error(err)
+ }
+ }
+ case *reflect.InterfaceType:
+ op = func(i *decInstr, state *decodeState, p unsafe.Pointer) {
+ dec.decodeInterface(t, state, uintptr(p), i.indir)
}
}
}
if op == nil {
- return nil, 0, os.ErrorString("gob: decode can't handle type " + rt.String())
+ errorf("gob: decode can't handle type %s", rt.String())
}
- return op, indir, nil
+ return op, indir
}
// Return the decoding op for a field that has no destination.
-func (dec *Decoder) decIgnoreOpFor(wireId typeId) (decOp, os.Error) {
+func (dec *Decoder) decIgnoreOpFor(wireId typeId) decOp {
op, ok := decIgnoreOpMap[wireId]
if !ok {
+ 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 *decodeState, p unsafe.Pointer) {
+ dec.ignoreInterface(state)
+ }
+ return op
+ }
// Special cases
wire := dec.wireType[wireId]
switch {
case wire == nil:
panic("internal error: can't find ignore op for type " + wireId.string())
- case wire.arrayT != nil:
- elemId := wire.arrayT.Elem
- elemOp, err := dec.decIgnoreOpFor(elemId)
- if err != nil {
- return nil, err
- }
+ case wire.ArrayT != nil:
+ elemId := wire.ArrayT.Elem
+ elemOp := dec.decIgnoreOpFor(elemId)
op = func(i *decInstr, state *decodeState, p unsafe.Pointer) {
- state.err = ignoreArray(state, elemOp, wire.arrayT.Len)
+ 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, err := dec.decIgnoreOpFor(keyId)
- if err != nil {
- return nil, err
- }
- elemOp, err := dec.decIgnoreOpFor(elemId)
- if err != nil {
- return nil, err
- }
+ case wire.MapT != nil:
+ keyId := dec.wireType[wireId].MapT.Key
+ elemId := dec.wireType[wireId].MapT.Elem
+ keyOp := dec.decIgnoreOpFor(keyId)
+ elemOp := dec.decIgnoreOpFor(elemId)
op = func(i *decInstr, state *decodeState, p unsafe.Pointer) {
- state.err = ignoreMap(state, keyOp, elemOp)
+ state.dec.ignoreMap(state, keyOp, elemOp)
}
- case wire.sliceT != nil:
- elemId := wire.sliceT.Elem
- elemOp, err := dec.decIgnoreOpFor(elemId)
- if err != nil {
- return nil, err
- }
+ case wire.SliceT != nil:
+ elemId := wire.SliceT.Elem
+ elemOp := dec.decIgnoreOpFor(elemId)
op = func(i *decInstr, state *decodeState, p unsafe.Pointer) {
- state.err = ignoreSlice(state, elemOp)
+ state.dec.ignoreSlice(state, elemOp)
}
- case wire.structT != nil:
+ 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 {
- return nil, err
+ error(err)
}
op = func(i *decInstr, state *decodeState, p unsafe.Pointer) {
// indirect through enginePtr to delay evaluation for recursive structs
- state.err = ignoreStruct(*enginePtr, state.b)
+ state.dec.ignoreStruct(*enginePtr, state.b)
}
}
}
if op == nil {
- return nil, os.ErrorString("ignore can't handle type " + wireId.string())
+ errorf("ignore can't handle type %s", wireId.string())
}
- return op, nil
+ return op
}
// Are these two gob Types compatible?
// Answers the question for basic types, arrays, and slices.
// Structs are considered ok; fields will be checked later.
func (dec *Decoder) compatibleType(fr reflect.Type, fw typeId) bool {
- for {
- if pt, ok := fr.(*reflect.PtrType); ok {
- fr = pt.Elem()
- continue
- }
- break
- }
+ fr, _ = indirect(fr)
switch t := fr.(type) {
default:
- // interface, map, chan, etc: cannot handle.
+ // map, chan, etc: cannot handle.
return false
case *reflect.BoolType:
return fw == tBool
@@ -786,20 +827,22 @@ func (dec *Decoder) compatibleType(fr reflect.Type, fw typeId) bool {
return fw == tComplex
case *reflect.StringType:
return fw == tString
+ case *reflect.InterfaceType:
+ return fw == tInterface
case *reflect.ArrayType:
wire, ok := dec.wireType[fw]
- if !ok || wire.arrayT == nil {
+ if !ok || wire.ArrayT == nil {
return false
}
- array := wire.arrayT
+ array := wire.ArrayT
return t.Len() == array.Len && dec.compatibleType(t.Elem(), array.Elem)
case *reflect.MapType:
wire, ok := dec.wireType[fw]
- if !ok || wire.mapT == nil {
+ if !ok || wire.MapT == nil {
return false
}
- mapType := wire.mapT
- return dec.compatibleType(t.Key(), mapType.Key) && dec.compatibleType(t.Elem(), mapType.Elem)
+ MapType := wire.MapT
+ return dec.compatibleType(t.Key(), MapType.Key) && dec.compatibleType(t.Elem(), MapType.Elem)
case *reflect.SliceType:
// Is it an array of bytes?
if t.Elem().Kind() == reflect.Uint8 {
@@ -810,7 +853,7 @@ func (dec *Decoder) compatibleType(fr reflect.Type, fw typeId) bool {
if tt, ok := builtinIdToType[fw]; ok {
sw = tt.(*sliceType)
} else {
- sw = dec.wireType[fw].sliceT
+ sw = dec.wireType[fw].SliceT
}
elem, _ := indirect(t.Elem())
return sw != nil && dec.compatibleType(elem, sw.Elem)
@@ -820,61 +863,74 @@ func (dec *Decoder) compatibleType(fr reflect.Type, fw typeId) bool {
return true
}
+// typeString returns a human-readable description of the type identified by remoteId.
+func (dec *Decoder) typeString(remoteId typeId) string {
+ if t := idToType[remoteId]; t != nil {
+ // globally known type.
+ return t.string()
+ }
+ return dec.wireType[remoteId].string()
+}
+
+
func (dec *Decoder) compileSingle(remoteId typeId, rt reflect.Type) (engine *decEngine, err os.Error) {
engine = new(decEngine)
engine.instr = make([]decInstr, 1) // one item
name := rt.String() // best we can do
if !dec.compatibleType(rt, remoteId) {
- return nil, os.ErrorString("gob: wrong type received for local value " + name)
- }
- op, indir, err := dec.decOpFor(remoteId, rt, name)
- if err != nil {
- return nil, err
+ return nil, os.ErrorString("gob: wrong type received for local value " + name + ": " + dec.typeString(remoteId))
}
+ op, indir := dec.decOpFor(remoteId, rt, name)
ovfl := os.ErrorString(`value for "` + name + `" out of range`)
engine.instr[singletonField] = decInstr{op, singletonField, indir, 0, ovfl}
engine.numInstr = 1
return
}
+// Is this an exported - upper case - name?
+func isExported(name string) bool {
+ rune, _ := utf8.DecodeRuneInString(name)
+ return unicode.IsUpper(rune)
+}
+
func (dec *Decoder) compileDec(remoteId typeId, rt reflect.Type) (engine *decEngine, err os.Error) {
+ defer catchError(&err)
srt, ok := rt.(*reflect.StructType)
if !ok {
return dec.compileSingle(remoteId, rt)
}
var wireStruct *structType
- // Builtin types can come from global pool; the rest must be defined by the decoder
+ // 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)
+ wireStruct, _ = t.(*structType)
} else {
- wireStruct = dec.wireType[remoteId].structT
+ wireStruct = dec.wireType[remoteId].StructT
+ }
+ if wireStruct == nil {
+ errorf("gob: type mismatch in decoder: want struct type %s; got non-struct", rt.String())
}
engine = new(decEngine)
- engine.instr = make([]decInstr, len(wireStruct.field))
+ engine.instr = make([]decInstr, len(wireStruct.Field))
// Loop over the fields of the wire type.
- for fieldnum := 0; fieldnum < len(wireStruct.field); fieldnum++ {
- wireField := wireStruct.field[fieldnum]
+ for fieldnum := 0; fieldnum < len(wireStruct.Field); fieldnum++ {
+ wireField := wireStruct.Field[fieldnum]
+ if wireField.Name == "" {
+ errorf("gob: 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)
- ovfl := overflow(wireField.name)
+ localField, present := srt.FieldByName(wireField.Name)
// TODO(r): anonymous names
- if !present {
- op, err := dec.decIgnoreOpFor(wireField.id)
- if err != nil {
- return nil, err
- }
+ if !present || !isExported(wireField.Name) {
+ op := dec.decIgnoreOpFor(wireField.Id)
engine.instr[fieldnum] = decInstr{op, fieldnum, 0, 0, ovfl}
continue
}
- if !dec.compatibleType(localField.Type, wireField.id) {
- return nil, os.ErrorString("gob: wrong type (" +
- localField.Type.String() + ") for received field " +
- wireStruct.name + "." + wireField.name)
- }
- op, indir, err := dec.decOpFor(wireField.id, localField.Type, localField.Name)
- if err != nil {
- return nil, err
+ if !dec.compatibleType(localField.Type, wireField.Id) {
+ errorf("gob: wrong type (%s) for received field %s.%s", localField.Type, wireStruct.Name, wireField.Name)
}
+ op, indir := dec.decOpFor(wireField.Id, localField.Type, localField.Name)
engine.instr[fieldnum] = decInstr{op, fieldnum, indir, uintptr(localField.Offset), ovfl}
engine.numInstr++
}
@@ -899,7 +955,7 @@ func (dec *Decoder) getDecEnginePtr(remoteId typeId, rt reflect.Type) (enginePtr
return
}
-// When ignoring data, in effect we compile it into this type
+// When ignoring struct data, in effect we compile it into this type
type emptyStruct struct{}
var emptyStructType = reflect.Typeof(emptyStruct{})
@@ -927,13 +983,13 @@ func (dec *Decoder) decode(wireId typeId, val reflect.Value) os.Error {
}
engine := *enginePtr
if st, ok := rt.(*reflect.StructType); ok {
- if engine.numInstr == 0 && st.NumField() > 0 && len(dec.wireType[wireId].structT.field) > 0 {
+ if engine.numInstr == 0 && st.NumField() > 0 && len(dec.wireType[wireId].StructT.Field) > 0 {
name := rt.Name()
return os.ErrorString("gob: type mismatch: no fields matched compiling decoder for " + name)
}
- return decodeStruct(engine, st, dec.state.b, uintptr(val.Addr()), indir)
+ return dec.decodeStruct(engine, st, dec.state.b, uintptr(val.Addr()), indir)
}
- return decodeSingle(engine, rt, dec.state.b, uintptr(val.Addr()), indir)
+ return dec.decodeSingle(engine, rt, dec.state.b, uintptr(val.Addr()), indir)
}
func init() {
generated by cgit v1.2.3 (git 2.39.1) at 2025-04-12 21:01:46 +0000