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-rw-r--r--libgo/go/encoding/binary/binary.go409
1 files changed, 409 insertions, 0 deletions
diff --git a/libgo/go/encoding/binary/binary.go b/libgo/go/encoding/binary/binary.go
new file mode 100644
index 000000000..77ff3a9f3
--- /dev/null
+++ b/libgo/go/encoding/binary/binary.go
@@ -0,0 +1,409 @@
+// 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
+ PutUint16([]byte, uint16)
+ PutUint32([]byte, uint32)
+ PutUint64([]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
+
+// LittleEndian is the little-endian implementation of ByteOrder.
+var LittleEndian littleEndian
+
+// BigEndian is the big-endian implementation of ByteOrder.
+var BigEndian bigEndian
+
+type littleEndian unused
+
+func (littleEndian) Uint16(b []byte) uint16 { return uint16(b[0]) | uint16(b[1])<<8 }
+
+func (littleEndian) PutUint16(b []byte, v uint16) {
+ b[0] = byte(v)
+ b[1] = byte(v >> 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) PutUint32(b []byte, v uint32) {
+ b[0] = byte(v)
+ b[1] = byte(v >> 8)
+ b[2] = byte(v >> 16)
+ b[3] = byte(v >> 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) PutUint64(b []byte, v uint64) {
+ b[0] = byte(v)
+ b[1] = byte(v >> 8)
+ b[2] = byte(v >> 16)
+ b[3] = byte(v >> 24)
+ b[4] = byte(v >> 32)
+ b[5] = byte(v >> 40)
+ b[6] = byte(v >> 48)
+ b[7] = byte(v >> 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) PutUint16(b []byte, v uint16) {
+ b[0] = byte(v >> 8)
+ b[1] = byte(v)
+}
+
+func (bigEndian) Uint32(b []byte) uint32 {
+ return uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24
+}
+
+func (bigEndian) PutUint32(b []byte, v uint32) {
+ b[0] = byte(v >> 24)
+ b[1] = byte(v >> 16)
+ b[2] = byte(v >> 8)
+ b[3] = byte(v)
+}
+
+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) PutUint64(b []byte, v uint64) {
+ b[0] = byte(v >> 56)
+ b[1] = byte(v >> 48)
+ b[2] = byte(v >> 40)
+ b[3] = byte(v >> 32)
+ b[4] = byte(v >> 24)
+ b[5] = byte(v >> 16)
+ b[6] = byte(v >> 8)
+ b[7] = byte(v)
+}
+
+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 or a slice
+// of fixed-size values.
+// A fixed-size value is either a fixed-size arithmetic
+// type (int8, uint8, int16, float32, complex64, ...)
+// or an array or struct containing only fixed-size values.
+// Bytes read from r are decoded using the specified byte order
+// and written to successive fields of the data.
+func Read(r io.Reader, order ByteOrder, data interface{}) os.Error {
+ var v reflect.Value
+ switch d := reflect.NewValue(data).(type) {
+ case *reflect.PtrValue:
+ v = d.Elem()
+ case *reflect.SliceValue:
+ v = d
+ default:
+ return os.NewError("binary.Read: invalid type " + d.Type().String())
+ }
+ size := TotalSize(v)
+ 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
+}
+
+// Write writes the binary representation of data into w.
+// Data must be a fixed-size value or a pointer to
+// a fixed-size value.
+// A fixed-size value is either a fixed-size arithmetic
+// type (int8, uint8, int16, float32, complex64, ...)
+// or an array or struct containing only fixed-size values.
+// Bytes written to w are encoded using the specified byte order
+// and read from successive fields of the data.
+func Write(w io.Writer, order ByteOrder, data interface{}) os.Error {
+ v := reflect.Indirect(reflect.NewValue(data))
+ size := TotalSize(v)
+ if size < 0 {
+ return os.NewError("binary.Write: invalid type " + v.Type().String())
+ }
+ buf := make([]byte, size)
+ e := &encoder{order: order, buf: buf}
+ e.value(v)
+ _, err := w.Write(buf)
+ return err
+}
+
+func TotalSize(v reflect.Value) int {
+ if sv, ok := v.(*reflect.SliceValue); ok {
+ elem := sizeof(v.Type().(*reflect.SliceType).Elem())
+ if elem < 0 {
+ return -1
+ }
+ return sv.Len() * elem
+ }
+ return sizeof(v.Type())
+}
+
+func sizeof(v reflect.Type) int {
+ switch t := v.(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.UintType, *reflect.IntType, *reflect.FloatType, *reflect.ComplexType:
+ switch t := t.Kind(); t {
+ case reflect.Int, reflect.Uint, reflect.Uintptr:
+ return -1
+ }
+ return int(v.Size())
+ }
+ return -1
+}
+
+type decoder struct {
+ order ByteOrder
+ buf []byte
+}
+
+type encoder struct {
+ order ByteOrder
+ buf []byte
+}
+
+func (d *decoder) uint8() uint8 {
+ x := d.buf[0]
+ d.buf = d.buf[1:]
+ return x
+}
+
+func (e *encoder) uint8(x uint8) {
+ e.buf[0] = x
+ e.buf = e.buf[1:]
+}
+
+func (d *decoder) uint16() uint16 {
+ x := d.order.Uint16(d.buf[0:2])
+ d.buf = d.buf[2:]
+ return x
+}
+
+func (e *encoder) uint16(x uint16) {
+ e.order.PutUint16(e.buf[0:2], x)
+ e.buf = e.buf[2:]
+}
+
+func (d *decoder) uint32() uint32 {
+ x := d.order.Uint32(d.buf[0:4])
+ d.buf = d.buf[4:]
+ return x
+}
+
+func (e *encoder) uint32(x uint32) {
+ e.order.PutUint32(e.buf[0:4], x)
+ e.buf = e.buf[4:]
+}
+
+func (d *decoder) uint64() uint64 {
+ x := d.order.Uint64(d.buf[0:8])
+ d.buf = d.buf[8:]
+ return x
+}
+
+func (e *encoder) uint64(x uint64) {
+ e.order.PutUint64(e.buf[0:8], x)
+ e.buf = e.buf[8:]
+}
+
+func (d *decoder) int8() int8 { return int8(d.uint8()) }
+
+func (e *encoder) int8(x int8) { e.uint8(uint8(x)) }
+
+func (d *decoder) int16() int16 { return int16(d.uint16()) }
+
+func (e *encoder) int16(x int16) { e.uint16(uint16(x)) }
+
+func (d *decoder) int32() int32 { return int32(d.uint32()) }
+
+func (e *encoder) int32(x int32) { e.uint32(uint32(x)) }
+
+func (d *decoder) int64() int64 { return int64(d.uint64()) }
+
+func (e *encoder) int64(x int64) { e.uint64(uint64(x)) }
+
+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.SliceValue:
+ l := v.Len()
+ for i := 0; i < l; i++ {
+ d.value(v.Elem(i))
+ }
+
+ case *reflect.IntValue:
+ switch v.Type().Kind() {
+ case reflect.Int8:
+ v.Set(int64(d.int8()))
+ case reflect.Int16:
+ v.Set(int64(d.int16()))
+ case reflect.Int32:
+ v.Set(int64(d.int32()))
+ case reflect.Int64:
+ v.Set(d.int64())
+ }
+
+ case *reflect.UintValue:
+ switch v.Type().Kind() {
+ case reflect.Uint8:
+ v.Set(uint64(d.uint8()))
+ case reflect.Uint16:
+ v.Set(uint64(d.uint16()))
+ case reflect.Uint32:
+ v.Set(uint64(d.uint32()))
+ case reflect.Uint64:
+ v.Set(d.uint64())
+ }
+
+ case *reflect.FloatValue:
+ switch v.Type().Kind() {
+ case reflect.Float32:
+ v.Set(float64(math.Float32frombits(d.uint32())))
+ case reflect.Float64:
+ v.Set(math.Float64frombits(d.uint64()))
+ }
+
+ case *reflect.ComplexValue:
+ switch v.Type().Kind() {
+ case reflect.Complex64:
+ v.Set(complex(
+ float64(math.Float32frombits(d.uint32())),
+ float64(math.Float32frombits(d.uint32())),
+ ))
+ case reflect.Complex128:
+ v.Set(complex(
+ math.Float64frombits(d.uint64()),
+ math.Float64frombits(d.uint64()),
+ ))
+ }
+ }
+}
+
+func (e *encoder) value(v reflect.Value) {
+ switch v := v.(type) {
+ case *reflect.ArrayValue:
+ l := v.Len()
+ for i := 0; i < l; i++ {
+ e.value(v.Elem(i))
+ }
+ case *reflect.StructValue:
+ l := v.NumField()
+ for i := 0; i < l; i++ {
+ e.value(v.Field(i))
+ }
+ case *reflect.SliceValue:
+ l := v.Len()
+ for i := 0; i < l; i++ {
+ e.value(v.Elem(i))
+ }
+
+ case *reflect.IntValue:
+ switch v.Type().Kind() {
+ case reflect.Int8:
+ e.int8(int8(v.Get()))
+ case reflect.Int16:
+ e.int16(int16(v.Get()))
+ case reflect.Int32:
+ e.int32(int32(v.Get()))
+ case reflect.Int64:
+ e.int64(v.Get())
+ }
+
+ case *reflect.UintValue:
+ switch v.Type().Kind() {
+ case reflect.Uint8:
+ e.uint8(uint8(v.Get()))
+ case reflect.Uint16:
+ e.uint16(uint16(v.Get()))
+ case reflect.Uint32:
+ e.uint32(uint32(v.Get()))
+ case reflect.Uint64:
+ e.uint64(v.Get())
+ }
+
+ case *reflect.FloatValue:
+ switch v.Type().Kind() {
+ case reflect.Float32:
+ e.uint32(math.Float32bits(float32(v.Get())))
+ case reflect.Float64:
+ e.uint64(math.Float64bits(v.Get()))
+ }
+
+ case *reflect.ComplexValue:
+ switch v.Type().Kind() {
+ case reflect.Complex64:
+ x := v.Get()
+ e.uint32(math.Float32bits(float32(real(x))))
+ e.uint32(math.Float32bits(float32(imag(x))))
+ case reflect.Complex128:
+ x := v.Get()
+ e.uint64(math.Float64bits(real(x)))
+ e.uint64(math.Float64bits(imag(x)))
+ }
+ }
+}