package debug/binary

R=austin
DELTA=320  (320 added, 0 deleted, 0 changed)
OCL=33983
CL=34143

src/pkg/Make.deps

@@ -16,6 +16,7 @@ crypto/hmac.install: crypto/md5.install crypto/sha1.install hash.install os.inst
 crypto/md5.install: hash.install os.install
 crypto/sha1.install: hash.install os.install
 datafmt.install: bytes.install container/vector.install fmt.install go/scanner.install go/token.install io.install os.install reflect.install runtime.install strconv.install strings.install
+debug/binary.install: io.install math.install os.install reflect.install
 debug/elf.install: fmt.install io.install os.install strconv.install
 ebnf.install: container/vector.install fmt.install go/scanner.install go/token.install os.install strconv.install strings.install unicode.install utf8.install
 exec.install: os.install strings.install

src/pkg/Makefile

@@ -30,6 +30,7 @@ DIRS=\
 	crypto/md5\
 	crypto/sha1\
 	datafmt\
+	debug/binary\
 	debug/elf\
 	ebnf\
 	exec\

src/pkg/debug/binary/Makefile

@@ -0,0 +1,11 @@
+# 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.
+
+include $(GOROOT)/src/Make.$(GOARCH)
+
+TARG=debug/binary
+GOFILES=\
+	binary.go\
+
+include $(GOROOT)/src/Make.pkg

src/pkg/debug/binary/binary.go

@@ -0,0 +1,220 @@
+// 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 binary
+
+import (
+	"math";
+	"io";
+	"os";
+	"reflect";
+)
+
+// A ByteOrder specifies how to convert byte sequences into
+// 16-, 32-, or 64-bit integers.
+type ByteOrder interface {
+	Uint16(b []byte) uint16;
+	Uint32(b []byte) uint32;
+	Uint64(b []byte) uint64;
+	String() string;
+}
+
+// This is byte instead of struct{} so that it can be compared,
+// allowing, e.g., order == binary.LittleEndian.
+type unused byte
+
+var LittleEndian ByteOrder = littleEndian(0)
+var BigEndian ByteOrder = bigEndian(0)
+
+type littleEndian unused
+
+func (littleEndian) Uint16(b []byte) uint16 {
+	return uint16(b[0]) | uint16(b[1])<<8;
+}
+
+func (littleEndian) Uint32(b []byte) uint32 {
+	return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24;
+}
+
+func (littleEndian) Uint64(b []byte) uint64 {
+	return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 |
+		uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56;
+}
+
+func (littleEndian) String() string {
+	return "LittleEndian";
+}
+
+func (littleEndian) GoString() string {
+	return "binary.LittleEndian";
+}
+
+type bigEndian unused
+
+func (bigEndian) Uint16(b []byte) uint16 {
+	return uint16(b[1]) | uint16(b[0])<<8;
+}
+
+func (bigEndian) Uint32(b []byte) uint32 {
+	return uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24;
+}
+
+func (bigEndian) Uint64(b []byte) uint64 {
+	return uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
+		uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56;
+}
+
+func (bigEndian) String() string {
+	return "BigEndian";
+}
+
+func (bigEndian) GoString() string {
+	return "binary.BigEndian";
+}
+
+// Read reads structured binary data from r into data.
+// Data must be a pointer to a fixed-size value.
+// A fixed-size value is either a fixed-size integer
+// (int8, uint8, int16, uint16, ...) or an array or struct
+// containing only fixed-size values.  Bytes read from
+// r are decoded using order and written to successive
+// fields of the data.
+func Read(r io.Reader, order ByteOrder, data interface{}) os.Error {
+	v := reflect.NewValue(data).(*reflect.PtrValue).Elem();
+	size := sizeof(v.Type());
+	if size < 0 {
+		return os.NewError("binary.Read: invalid type " + v.Type().String());
+	}
+	d := &decoder{order: order, buf: make([]byte, size)};
+	if n, err := io.ReadFull(r, d.buf); err != nil {
+		return err;
+	}
+	d.value(v);
+	return nil;
+}
+
+func sizeof(t reflect.Type) int {
+	switch t := t.(type) {
+	case *reflect.ArrayType:
+		n := sizeof(t.Elem());
+		if n < 0 {
+			return -1;
+		}
+		return t.Len() * n;
+
+	case *reflect.StructType:
+		sum := 0;
+		for i, n := 0, t.NumField(); i < n; i++ {
+			s := sizeof(t.Field(i).Type);
+			if s < 0 {
+				return -1;
+			}
+			sum += s;
+		}
+		return sum;
+
+	case *reflect.Uint8Type:
+		return 1;
+	case *reflect.Uint16Type:
+		return 2;
+	case *reflect.Uint32Type:
+		return 4;
+	case *reflect.Uint64Type:
+		return 8;
+	case *reflect.Int8Type:
+		return 1;
+	case *reflect.Int16Type:
+		return 2;
+	case *reflect.Int32Type:
+		return 4;
+	case *reflect.Int64Type:
+		return 8;
+	case *reflect.Float32Type:
+		return 4;
+	case *reflect.Float64Type:
+		return 8;
+	}
+	return -1;
+}
+
+type decoder struct {
+	order ByteOrder;
+	buf []byte;
+}
+
+func (d *decoder) uint8() uint8 {
+	x := d.buf[0];
+	d.buf = d.buf[1:len(d.buf)];
+	return x;
+}
+
+func (d *decoder) uint16() uint16 {
+	x := d.order.Uint16(d.buf[0:2]);
+	d.buf = d.buf[2:len(d.buf)];
+	return x;
+}
+
+func (d *decoder) uint32() uint32 {
+	x := d.order.Uint32(d.buf[0:4]);
+	d.buf = d.buf[4:len(d.buf)];
+	return x;
+}
+
+func (d *decoder) uint64() uint64 {
+	x := d.order.Uint64(d.buf[0:8]);
+	d.buf = d.buf[8:len(d.buf)];
+	return x;
+}
+
+func (d *decoder) int8() int8 {
+	return int8(d.uint8());
+}
+
+func (d *decoder) int16() int16 {
+	return int16(d.uint16());
+}
+
+func (d *decoder) int32() int32 {
+	return int32(d.uint32());
+}
+
+func (d *decoder) int64() int64 {
+	return int64(d.uint64());
+}
+
+func (d *decoder) value(v reflect.Value) {
+	switch v := v.(type) {
+	case *reflect.ArrayValue:
+		l := v.Len();
+		for i := 0; i < l; i++ {
+			d.value(v.Elem(i));
+		}
+	case *reflect.StructValue:
+		l := v.NumField();
+		for i := 0; i < l; i++ {
+			d.value(v.Field(i));
+		}
+
+	case *reflect.Uint8Value:
+		v.Set(d.uint8());
+	case *reflect.Uint16Value:
+		v.Set(d.uint16());
+	case *reflect.Uint32Value:
+		v.Set(d.uint32());
+	case *reflect.Uint64Value:
+		v.Set(d.uint64());
+	case *reflect.Int8Value:
+		v.Set(d.int8());
+	case *reflect.Int16Value:
+		v.Set(d.int16());
+	case *reflect.Int32Value:
+		v.Set(d.int32());
+	case *reflect.Int64Value:
+		v.Set(d.int64());
+	case *reflect.Float32Value:
+		v.Set(math.Float32frombits(d.uint32()));
+	case *reflect.Float64Value:
+		v.Set(math.Float64frombits(d.uint64()));
+	}
+}

src/pkg/debug/binary/binary_test.go

@@ -0,0 +1,87 @@
+// 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 binary
+
+import (
+	"bytes";
+	"math";
+	"reflect";
+	"testing";
+)
+
+type Struct struct {
+	Int8 int8;
+	Int16 int16;
+	Int32 int32;
+	Int64 int64;
+	Uint8 uint8;
+	Uint16 uint16;
+	Uint32 uint32;
+	Uint64 uint64;
+	Float64 float64;
+	Array [4]uint8;
+}
+
+var s = Struct {
+	0x01,
+	0x0203,
+	0x04050607,
+	0x08090a0b0c0d0e0f,
+	0x10,
+	0x1112,
+	0x13141516,
+	0x1718191a1b1c1d1e,
+	math.Float64frombits(0x1f20212223242526),
+	[4]uint8 { 0x27, 0x28, 0x29, 0x2a },
+}
+
+var big = []byte{
+	1,
+	2, 3,
+	4, 5, 6, 7,
+	8, 9, 10, 11, 12, 13, 14, 15,
+	16,
+	17, 18,
+	19, 20, 21, 22,
+	23, 24, 25, 26, 27, 28, 29, 30,
+	31, 32, 33, 34, 35, 36, 37, 38,
+	39, 40, 41, 42,
+}
+
+var little = []byte{
+	1,
+	3, 2,
+	7, 6, 5, 4,
+	15, 14, 13, 12, 11, 10, 9, 8,
+	16,
+	18, 17,
+	22, 21, 20, 19,
+	30, 29, 28, 27, 26, 25, 24, 23,
+	38, 37, 36, 35, 34, 33, 32, 31,
+	39, 40, 41, 42,
+}
+
+func TestRead(t *testing.T) {
+	var sl, sb Struct;
+
+	err := Read(bytes.NewBuffer(big), BigEndian, &sb);
+	if err != nil {
+		t.Errorf("Read big-endian: %v", err);
+		goto little;
+	}
+	if !reflect.DeepEqual(sb, s) {
+		t.Errorf("Read big-endian:\n\thave %+v\n\twant %+v", sb, s);
+	}
+
+little:
+	err = Read(bytes.NewBuffer(little), LittleEndian, &sl);
+	if err != nil {
+		t.Errorf("Read little-endian: %v", err);
+	}
+	if !reflect.DeepEqual(sl, s) {
+		t.Errorf("Read big-endian:\n\thave %+v\n\twant %+v", sl, s);
+	}
+}
+