1 files changed, 222 insertions, 0 deletions
diff --git a/src/pkg/encoding/binary/binary.go b/src/pkg/encoding/binary/binary.go
new file mode 100644
index 000000000..836a43df0
--- /dev/null
+++ b/src/pkg/encoding/binary/binary.go
@@ -0,0 +1,222 @@
+// 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.
+
+// This package implements translation between
+// unsigned integer values and byte sequences.
+package binary
+
+import (
+	"math";
+	"io";
+	"os";
+	"reflect";
+)
+
+// A ByteOrder specifies how to convert byte sequences into
+// 16-, 32-, or 64-bit unsigned 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 _, 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()));
+	}
+}