mirror of
https://github.com/golang/go
synced 2024-10-03 08:21:21 -06:00
pass the state to the encoders and decoders so error handling can be centralized.
R=rsc DELTA=172 (40 added, 6 deleted, 126 changed) OCL=30941 CL=30944
This commit is contained in:
parent
f6f825141a
commit
79b2cf92d9
@ -36,26 +36,30 @@ var encodeT = []EncodeT {
|
||||
|
||||
// Test basic encode/decode routines for unsigned integers
|
||||
func TestUintCodec(t *testing.T) {
|
||||
var b = new(bytes.Buffer);
|
||||
b := new(bytes.Buffer);
|
||||
encState := new(EncState);
|
||||
encState.w = b;
|
||||
for i, tt := range encodeT {
|
||||
b.Reset();
|
||||
err := EncodeUint(b, tt.x);
|
||||
if err != nil {
|
||||
t.Error("EncodeUint:", tt.x, err)
|
||||
EncodeUint(encState, tt.x);
|
||||
if encState.err != nil {
|
||||
t.Error("EncodeUint:", tt.x, encState.err)
|
||||
}
|
||||
if !bytes.Equal(tt.b, b.Data()) {
|
||||
t.Errorf("EncodeUint: expected % x got % x", tt.b, b.Data())
|
||||
}
|
||||
}
|
||||
decState := new(DecState);
|
||||
decState.r = b;
|
||||
for u := uint64(0); ; u = (u+1) * 7 {
|
||||
b.Reset();
|
||||
err := EncodeUint(b, u);
|
||||
if err != nil {
|
||||
t.Error("EncodeUint:", u, err)
|
||||
EncodeUint(encState, u);
|
||||
if encState.err != nil {
|
||||
t.Error("EncodeUint:", u, encState.err)
|
||||
}
|
||||
v, err := DecodeUint(b);
|
||||
if err != nil {
|
||||
t.Error("DecodeUint:", u, err)
|
||||
v := DecodeUint(decState);
|
||||
if decState.err != nil {
|
||||
t.Error("DecodeUint:", u, decState.err)
|
||||
}
|
||||
if u != v {
|
||||
t.Errorf("Encode/Decode: sent %#x received %#x\n", u, v)
|
||||
@ -68,13 +72,17 @@ func TestUintCodec(t *testing.T) {
|
||||
|
||||
func verifyInt(i int64, t *testing.T) {
|
||||
var b = new(bytes.Buffer);
|
||||
err := EncodeInt(b, i);
|
||||
if err != nil {
|
||||
t.Error("EncodeInt:", i, err)
|
||||
encState := new(EncState);
|
||||
encState.w = b;
|
||||
EncodeInt(encState, i);
|
||||
if encState.err != nil {
|
||||
t.Error("EncodeInt:", i, encState.err)
|
||||
}
|
||||
j, err := DecodeInt(b);
|
||||
if err != nil {
|
||||
t.Error("DecodeInt:", i, err)
|
||||
decState := new(DecState);
|
||||
decState.r = b;
|
||||
j := DecodeInt(decState);
|
||||
if decState.err != nil {
|
||||
t.Error("DecodeInt:", i, decState.err)
|
||||
}
|
||||
if i != j {
|
||||
t.Errorf("Encode/Decode: sent %#x received %#x\n", uint64(i), uint64(j))
|
||||
@ -109,7 +117,7 @@ var floatResult = []byte{0x80, 0x40, 0xe2, 0x81, 0x40, 0xe2, 0x82, 0x40, 0xe2}
|
||||
// Do not run the machine yet; instead do individual instructions crafted by hand.
|
||||
func TestScalarEncInstructions(t *testing.T) {
|
||||
var b = new(bytes.Buffer);
|
||||
var state encState;
|
||||
var state EncState;
|
||||
|
||||
// bool
|
||||
{
|
||||
|
@ -7,34 +7,48 @@ package gob
|
||||
import (
|
||||
"io";
|
||||
"os";
|
||||
"unsafe";
|
||||
)
|
||||
|
||||
// DecodeUint reads an encoded unsigned integer from r.
|
||||
func DecodeUint(r io.Reader) (x uint64, err os.Error) {
|
||||
var buf [1]byte;
|
||||
// The global execution state of an instance of the decoder.
|
||||
type DecState struct {
|
||||
r io.Reader;
|
||||
err os.Error;
|
||||
base uintptr;
|
||||
buf [1]byte; // buffer used by the decoder; here to avoid allocation.
|
||||
}
|
||||
|
||||
// DecodeUint reads an encoded unsigned integer from state.r.
|
||||
// Sets state.err. If state.err is already non-nil, it does nothing.
|
||||
func DecodeUint(state *DecState) (x uint64) {
|
||||
if state.err != nil {
|
||||
return
|
||||
}
|
||||
for shift := uint(0);; shift += 7 {
|
||||
n, err := r.Read(&buf);
|
||||
var n int;
|
||||
n, state.err = state.r.Read(&state.buf);
|
||||
if n != 1 {
|
||||
return 0, err
|
||||
return 0
|
||||
}
|
||||
b := uint64(buf[0]);
|
||||
b := uint64(state.buf[0]);
|
||||
x |= b << shift;
|
||||
if b&0x80 != 0 {
|
||||
x &^= 0x80 << shift;
|
||||
break
|
||||
}
|
||||
}
|
||||
return x, nil;
|
||||
return x;
|
||||
}
|
||||
|
||||
// DecodeInt reads an encoded signed integer from r.
|
||||
func DecodeInt(r io.Reader) (i int64, err os.Error) {
|
||||
x, err := DecodeUint(r);
|
||||
if err != nil {
|
||||
return
|
||||
// DecodeInt reads an encoded signed integer from state.r.
|
||||
// Sets state.err. If state.err is already non-nil, it does nothing.
|
||||
func DecodeInt(state *DecState) int64 {
|
||||
x := DecodeUint(state);
|
||||
if state.err != nil {
|
||||
return 0
|
||||
}
|
||||
if x & 1 != 0 {
|
||||
return ^int64(x>>1), nil
|
||||
return ^int64(x>>1)
|
||||
}
|
||||
return int64(x >> 1), nil
|
||||
return int64(x >> 1)
|
||||
}
|
||||
|
@ -11,51 +11,63 @@ import (
|
||||
"unsafe";
|
||||
)
|
||||
|
||||
// The global execution state of an instance of the encoder.
|
||||
type EncState struct {
|
||||
w io.Writer;
|
||||
base uintptr; // the base address of the data structure being written
|
||||
err os.Error; // error encountered during encoding;
|
||||
buf [16]byte; // buffer used by the encoder; here to avoid allocation.
|
||||
}
|
||||
|
||||
// Integers encode as a variant of Google's protocol buffer varint (varvarint?).
|
||||
// The variant is that the continuation bytes have a zero top bit instead of a one.
|
||||
// That way there's only one bit to clear and the value is a little easier to see if
|
||||
// you're the unfortunate sort of person who must read the hex to debug.
|
||||
|
||||
// EncodeUint writes an encoded unsigned integer to w.
|
||||
func EncodeUint(w io.Writer, x uint64) os.Error {
|
||||
var buf [16]byte;
|
||||
// EncodeUint writes an encoded unsigned integer to state.w. Sets state.err.
|
||||
// If state.err is already non-nil, it does nothing.
|
||||
func EncodeUint(state *EncState, x uint64) {
|
||||
var n int;
|
||||
if state.err != nil {
|
||||
return
|
||||
}
|
||||
for n = 0; x > 127; n++ {
|
||||
buf[n] = uint8(x & 0x7F);
|
||||
state.buf[n] = uint8(x & 0x7F);
|
||||
x >>= 7;
|
||||
}
|
||||
buf[n] = 0x80 | uint8(x);
|
||||
nn, err := w.Write(buf[0:n+1]);
|
||||
return err;
|
||||
state.buf[n] = 0x80 | uint8(x);
|
||||
var nn int;
|
||||
nn, state.err = state.w.Write(state.buf[0:n+1]);
|
||||
}
|
||||
|
||||
// EncodeInt writes an encoded signed integer to w.
|
||||
// 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 EncodeInt(w io.Writer, i int64) os.Error {
|
||||
// Sets state.err. If state.err is already non-nil, it does nothing.
|
||||
func EncodeInt(state *EncState, i int64){
|
||||
var x uint64;
|
||||
if i < 0 {
|
||||
x = uint64(^i << 1) | 1
|
||||
} else {
|
||||
x = uint64(i << 1)
|
||||
}
|
||||
return EncodeUint(w, uint64(x))
|
||||
}
|
||||
|
||||
// The global execution state of an instance of the encoder.
|
||||
type encState struct {
|
||||
w io.Writer;
|
||||
base uintptr;
|
||||
EncodeUint(state, uint64(x))
|
||||
}
|
||||
|
||||
// The 'instructions' of the encoding machine
|
||||
type encInstr struct {
|
||||
op func(i *encInstr, state *encState);
|
||||
op func(i *encInstr, state *EncState);
|
||||
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
|
||||
}
|
||||
|
||||
func encBool(i *encInstr, state *encState) {
|
||||
// Each encoder is responsible for handling any indirections associated
|
||||
// with the data structure. If any pointer so reached is nil, no bytes are written.
|
||||
// If the data item is zero, no bytes are written.
|
||||
// Otherwise, the output (for a scalar) is the field number, as an encoded integer,
|
||||
// followed by the field data in its appropriate format.
|
||||
|
||||
func encBool(i *encInstr, state *EncState) {
|
||||
p := unsafe.Pointer(state.base+i.offset);
|
||||
for indir := i.indir; indir > 0; indir-- {
|
||||
p = *(*unsafe.Pointer)(p);
|
||||
@ -65,12 +77,12 @@ func encBool(i *encInstr, state *encState) {
|
||||
}
|
||||
b := *(*bool)(p);
|
||||
if b {
|
||||
EncodeUint(state.w, uint64(i.field));
|
||||
EncodeUint(state.w, 1);
|
||||
EncodeUint(state, uint64(i.field));
|
||||
EncodeUint(state, 1);
|
||||
}
|
||||
}
|
||||
|
||||
func encInt(i *encInstr, state *encState) {
|
||||
func encInt(i *encInstr, state *EncState) {
|
||||
p := unsafe.Pointer(state.base+i.offset);
|
||||
for indir := i.indir; indir > 0; indir-- {
|
||||
p = *(*unsafe.Pointer)(p);
|
||||
@ -80,12 +92,12 @@ func encInt(i *encInstr, state *encState) {
|
||||
}
|
||||
v := int64(*(*int)(p));
|
||||
if v != 0 {
|
||||
EncodeUint(state.w, uint64(i.field));
|
||||
EncodeInt(state.w, v);
|
||||
EncodeUint(state, uint64(i.field));
|
||||
EncodeInt(state, v);
|
||||
}
|
||||
}
|
||||
|
||||
func encUint(i *encInstr, state *encState) {
|
||||
func encUint(i *encInstr, state *EncState) {
|
||||
p := unsafe.Pointer(state.base+i.offset);
|
||||
for indir := i.indir; indir > 0; indir-- {
|
||||
p = *(*unsafe.Pointer)(p);
|
||||
@ -95,12 +107,12 @@ func encUint(i *encInstr, state *encState) {
|
||||
}
|
||||
v := uint64(*(*uint)(p));
|
||||
if v != 0 {
|
||||
EncodeUint(state.w, uint64(i.field));
|
||||
EncodeUint(state.w, v);
|
||||
EncodeUint(state, uint64(i.field));
|
||||
EncodeUint(state, v);
|
||||
}
|
||||
}
|
||||
|
||||
func encInt8(i *encInstr, state *encState) {
|
||||
func encInt8(i *encInstr, state *EncState) {
|
||||
p := unsafe.Pointer(state.base+i.offset);
|
||||
for indir := i.indir; indir > 0; indir-- {
|
||||
p = *(*unsafe.Pointer)(p);
|
||||
@ -110,12 +122,12 @@ func encInt8(i *encInstr, state *encState) {
|
||||
}
|
||||
v := int64(*(*int8)(p));
|
||||
if v != 0 {
|
||||
EncodeUint(state.w, uint64(i.field));
|
||||
EncodeInt(state.w, v);
|
||||
EncodeUint(state, uint64(i.field));
|
||||
EncodeInt(state, v);
|
||||
}
|
||||
}
|
||||
|
||||
func encUint8(i *encInstr, state *encState) {
|
||||
func encUint8(i *encInstr, state *EncState) {
|
||||
p := unsafe.Pointer(state.base+i.offset);
|
||||
for indir := i.indir; indir > 0; indir-- {
|
||||
p = *(*unsafe.Pointer)(p);
|
||||
@ -125,12 +137,12 @@ func encUint8(i *encInstr, state *encState) {
|
||||
}
|
||||
v := uint64(*(*uint8)(p));
|
||||
if v != 0 {
|
||||
EncodeUint(state.w, uint64(i.field));
|
||||
EncodeUint(state.w, v);
|
||||
EncodeUint(state, uint64(i.field));
|
||||
EncodeUint(state, v);
|
||||
}
|
||||
}
|
||||
|
||||
func encInt16(i *encInstr, state *encState) {
|
||||
func encInt16(i *encInstr, state *EncState) {
|
||||
p := unsafe.Pointer(state.base+i.offset);
|
||||
for indir := i.indir; indir > 0; indir-- {
|
||||
p = *(*unsafe.Pointer)(p);
|
||||
@ -140,12 +152,12 @@ func encInt16(i *encInstr, state *encState) {
|
||||
}
|
||||
v := int64(*(*int16)(p));
|
||||
if v != 0 {
|
||||
EncodeUint(state.w, uint64(i.field));
|
||||
EncodeInt(state.w, v);
|
||||
EncodeUint(state, uint64(i.field));
|
||||
EncodeInt(state, v);
|
||||
}
|
||||
}
|
||||
|
||||
func encUint16(i *encInstr, state *encState) {
|
||||
func encUint16(i *encInstr, state *EncState) {
|
||||
p := unsafe.Pointer(state.base+i.offset);
|
||||
for indir := i.indir; indir > 0; indir-- {
|
||||
p = *(*unsafe.Pointer)(p);
|
||||
@ -155,12 +167,12 @@ func encUint16(i *encInstr, state *encState) {
|
||||
}
|
||||
v := uint64(*(*uint16)(p));
|
||||
if v != 0 {
|
||||
EncodeUint(state.w, uint64(i.field));
|
||||
EncodeUint(state.w, v);
|
||||
EncodeUint(state, uint64(i.field));
|
||||
EncodeUint(state, v);
|
||||
}
|
||||
}
|
||||
|
||||
func encInt32(i *encInstr, state *encState) {
|
||||
func encInt32(i *encInstr, state *EncState) {
|
||||
p := unsafe.Pointer(state.base+i.offset);
|
||||
for indir := i.indir; indir > 0; indir-- {
|
||||
p = *(*unsafe.Pointer)(p);
|
||||
@ -170,12 +182,12 @@ func encInt32(i *encInstr, state *encState) {
|
||||
}
|
||||
v := int64(*(*int32)(p));
|
||||
if v != 0 {
|
||||
EncodeUint(state.w, uint64(i.field));
|
||||
EncodeInt(state.w, v);
|
||||
EncodeUint(state, uint64(i.field));
|
||||
EncodeInt(state, v);
|
||||
}
|
||||
}
|
||||
|
||||
func encUint32(i *encInstr, state *encState) {
|
||||
func encUint32(i *encInstr, state *EncState) {
|
||||
p := unsafe.Pointer(state.base+i.offset);
|
||||
for indir := i.indir; indir > 0; indir-- {
|
||||
p = *(*unsafe.Pointer)(p);
|
||||
@ -185,12 +197,12 @@ func encUint32(i *encInstr, state *encState) {
|
||||
}
|
||||
v := uint64(*(*uint32)(p));
|
||||
if v != 0 {
|
||||
EncodeUint(state.w, uint64(i.field));
|
||||
EncodeUint(state.w, v);
|
||||
EncodeUint(state, uint64(i.field));
|
||||
EncodeUint(state, v);
|
||||
}
|
||||
}
|
||||
|
||||
func encInt64(i *encInstr, state *encState) {
|
||||
func encInt64(i *encInstr, state *EncState) {
|
||||
p := unsafe.Pointer(state.base+i.offset);
|
||||
for indir := i.indir; indir > 0; indir-- {
|
||||
p = *(*unsafe.Pointer)(p);
|
||||
@ -200,12 +212,12 @@ func encInt64(i *encInstr, state *encState) {
|
||||
}
|
||||
v := *(*int64)(p);
|
||||
if v != 0 {
|
||||
EncodeUint(state.w, uint64(i.field));
|
||||
EncodeInt(state.w, v);
|
||||
EncodeUint(state, uint64(i.field));
|
||||
EncodeInt(state, v);
|
||||
}
|
||||
}
|
||||
|
||||
func encUint64(i *encInstr, state *encState) {
|
||||
func encUint64(i *encInstr, state *EncState) {
|
||||
p := unsafe.Pointer(state.base+i.offset);
|
||||
for indir := i.indir; indir > 0; indir-- {
|
||||
p = *(*unsafe.Pointer)(p);
|
||||
@ -215,8 +227,8 @@ func encUint64(i *encInstr, state *encState) {
|
||||
}
|
||||
v := *(*uint64)(p);
|
||||
if v != 0 {
|
||||
EncodeUint(state.w, uint64(i.field));
|
||||
EncodeUint(state.w, v);
|
||||
EncodeUint(state, uint64(i.field));
|
||||
EncodeUint(state, v);
|
||||
}
|
||||
}
|
||||
|
||||
@ -236,7 +248,7 @@ func floatBits(f float64) uint64 {
|
||||
return v;
|
||||
}
|
||||
|
||||
func encFloat(i *encInstr, state *encState) {
|
||||
func encFloat(i *encInstr, state *EncState) {
|
||||
p := unsafe.Pointer(state.base+i.offset);
|
||||
for indir := i.indir; indir > 0; indir-- {
|
||||
p = *(*unsafe.Pointer)(p);
|
||||
@ -247,12 +259,12 @@ func encFloat(i *encInstr, state *encState) {
|
||||
f := float(*(*float)(p));
|
||||
if f != 0 {
|
||||
v := floatBits(float64(f));
|
||||
EncodeUint(state.w, uint64(i.field));
|
||||
EncodeUint(state.w, v);
|
||||
EncodeUint(state, uint64(i.field));
|
||||
EncodeUint(state, v);
|
||||
}
|
||||
}
|
||||
|
||||
func encFloat32(i *encInstr, state *encState) {
|
||||
func encFloat32(i *encInstr, state *EncState) {
|
||||
p := unsafe.Pointer(state.base+i.offset);
|
||||
for indir := i.indir; indir > 0; indir-- {
|
||||
p = *(*unsafe.Pointer)(p);
|
||||
@ -263,12 +275,12 @@ func encFloat32(i *encInstr, state *encState) {
|
||||
f := float32(*(*float32)(p));
|
||||
if f != 0 {
|
||||
v := floatBits(float64(f));
|
||||
EncodeUint(state.w, uint64(i.field));
|
||||
EncodeUint(state.w, v);
|
||||
EncodeUint(state, uint64(i.field));
|
||||
EncodeUint(state, v);
|
||||
}
|
||||
}
|
||||
|
||||
func encFloat64(i *encInstr, state *encState) {
|
||||
func encFloat64(i *encInstr, state *EncState) {
|
||||
p := unsafe.Pointer(state.base+i.offset);
|
||||
for indir := i.indir; indir > 0; indir-- {
|
||||
p = *(*unsafe.Pointer)(p);
|
||||
@ -279,7 +291,7 @@ func encFloat64(i *encInstr, state *encState) {
|
||||
f := *(*float64)(p);
|
||||
if f != 0 {
|
||||
v := floatBits(f);
|
||||
EncodeUint(state.w, uint64(i.field));
|
||||
EncodeUint(state.w, v);
|
||||
EncodeUint(state, uint64(i.field));
|
||||
EncodeUint(state, v);
|
||||
}
|
||||
}
|
||||
|
Loading…
Reference in New Issue
Block a user