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R=rsc
DELTA=59  (44 added, 13 deleted, 2 changed)
OCL=31105
CL=31105
This commit is contained in:
Rob Pike 2009-07-02 18:02:42 -07:00
parent c1fc4c8f37
commit 265674fa57
2 changed files with 46 additions and 15 deletions
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57
src/pkg/gob/decode.go
View file

@ -313,21 +313,8 @@ func decodeStruct(engine *decEngine, rtyp reflect.StructType, r io.Reader, p uin
return state.err
}
func decodeArray(atyp reflect.ArrayType, state *DecState, p uintptr, elemOp decOp, elemWid int, length int, indir, elemIndir int) os.Error {
if indir > 0 {
up := unsafe.Pointer(p);
if *(*unsafe.Pointer)(up) == nil {
// Allocate the structure by making a slice of bytes and recording the
// address of the beginning of the array. TODO(rsc).
b := make([]byte, atyp.Size());
*(*unsafe.Pointer)(up) = unsafe.Pointer(&b[0]);
}
p = *(*uintptr)(up);
}
func decodeArrayHelper(state *DecState, p uintptr, elemOp decOp, elemWid, length, elemIndir int) os.Error {
instr := &decInstr{elemOp, 0, elemIndir, 0};
if DecodeUint(state) != uint64(length) {
state.err = os.ErrorString("length mismatch in decodeArray");
}
for i := 0; i < length && state.err == nil; i++ {
up := unsafe.Pointer(p);
if elemIndir > 1 {
@ -339,6 +326,43 @@ func decodeArray(atyp reflect.ArrayType, state *DecState, p uintptr, elemOp decO
return state.err
}
func decodeArray(atyp reflect.ArrayType, state *DecState, p uintptr, elemOp decOp, elemWid, length, indir, elemIndir int) os.Error {
if indir > 0 {
up := unsafe.Pointer(p);
if *(*unsafe.Pointer)(up) == nil {
// Allocate the array by making a slice of bytes of the correct size
// and taking the address of the beginning of the array. TODO(rsc).
b := make([]byte, atyp.Size());
*(**byte)(up) = &b[0];
}
p = *(*uintptr)(up);
}
if DecodeUint(state) != uint64(length) {
return os.ErrorString("length mismatch in decodeArray");
}
return decodeArrayHelper(state, p, elemOp, elemWid, length, elemIndir);
}
func decodeSlice(atyp reflect.ArrayType, state *DecState, p uintptr, elemOp decOp, elemWid, indir, elemIndir int) os.Error {
length := int(DecodeUint(state));
if indir > 0 {
up := unsafe.Pointer(p);
if *(*unsafe.Pointer)(up) == nil {
// Allocate the slice header.
*(*unsafe.Pointer)(up) = unsafe.Pointer(new(reflect.SliceHeader));
}
p = *(*uintptr)(up);
}
// Allocate storage for the slice elements, that is, the underlying array.
data := make([]byte, length*atyp.Elem().Size());
// Always write a header at p.
hdrp := (*reflect.SliceHeader)(unsafe.Pointer(p));
hdrp.Data = uintptr(unsafe.Pointer(&data[0]));
hdrp.Len = uint32(length);
hdrp.Cap = uint32(length);
return decodeArrayHelper(state, hdrp.Data, elemOp, elemWid, length, elemIndir);
}
var decEngineMap = make(map[reflect.Type] *decEngine)
var decOpMap = map[int] decOp {
reflect.BoolKind: decBool,
@ -370,6 +394,11 @@ func decOpFor(typ reflect.Type) decOp {
case atyp.Elem().Kind() == reflect.Uint8Kind:
op = decUint8Array
case atyp.IsSlice():
elemOp := decOpFor(atyp.Elem());
_, elemIndir := indirect(atyp.Elem());
op = func(i *decInstr, state *DecState, p unsafe.Pointer) {
state.err = decodeSlice(atyp, state, uintptr(p), elemOp, atyp.Elem().Size(), i.indir, elemIndir);
};
case !atyp.IsSlice():
elemOp := decOpFor(atyp.Elem());
_, elemIndir := indirect(atyp.Elem());