170 lines
3.0 KiB
Go
170 lines
3.0 KiB
Go
// Copyright (C) 2014 Jakob Borg and other contributors. All rights reserved.
|
|
// Use of this source code is governed by an MIT-style license that can be
|
|
// found in the LICENSE file.
|
|
|
|
package xdr
|
|
|
|
import (
|
|
"errors"
|
|
"io"
|
|
"time"
|
|
)
|
|
|
|
var ErrElementSizeExceeded = errors.New("element size exceeded")
|
|
|
|
type Reader struct {
|
|
r io.Reader
|
|
tot int
|
|
err error
|
|
b [8]byte
|
|
last time.Time
|
|
}
|
|
|
|
func NewReader(r io.Reader) *Reader {
|
|
return &Reader{
|
|
r: r,
|
|
}
|
|
}
|
|
|
|
func (r *Reader) ReadString() string {
|
|
return string(r.ReadBytes())
|
|
}
|
|
|
|
func (r *Reader) ReadStringMax(max int) string {
|
|
return string(r.ReadBytesMax(max))
|
|
}
|
|
|
|
func (r *Reader) ReadBytes() []byte {
|
|
return r.ReadBytesInto(nil)
|
|
}
|
|
|
|
func (r *Reader) ReadBytesMax(max int) []byte {
|
|
return r.ReadBytesMaxInto(max, nil)
|
|
}
|
|
|
|
func (r *Reader) ReadBytesInto(dst []byte) []byte {
|
|
return r.ReadBytesMaxInto(0, dst)
|
|
}
|
|
|
|
func (r *Reader) ReadBytesMaxInto(max int, dst []byte) []byte {
|
|
if r.err != nil {
|
|
return nil
|
|
}
|
|
r.last = time.Now()
|
|
s := r.tot
|
|
|
|
l := int(r.ReadUint32())
|
|
if r.err != nil {
|
|
return nil
|
|
}
|
|
if max > 0 && l > max {
|
|
r.err = ErrElementSizeExceeded
|
|
return nil
|
|
}
|
|
|
|
if l+pad(l) > len(dst) {
|
|
dst = make([]byte, l+pad(l))
|
|
} else {
|
|
dst = dst[:l+pad(l)]
|
|
}
|
|
|
|
var n int
|
|
n, r.err = io.ReadFull(r.r, dst)
|
|
if r.err != nil {
|
|
dl.Debugf("@0x%x: rd bytes (%d): %v", s, len(dst), r.err)
|
|
return nil
|
|
}
|
|
r.tot += n
|
|
|
|
if debug {
|
|
if n > maxDebugBytes {
|
|
dl.Debugf("@0x%x: rd bytes (%d): %x...", s, len(dst), dst[:maxDebugBytes])
|
|
} else {
|
|
dl.Debugf("@0x%x: rd bytes (%d): %x", s, len(dst), dst)
|
|
}
|
|
}
|
|
return dst[:l]
|
|
}
|
|
|
|
func (r *Reader) ReadUint16() uint16 {
|
|
if r.err != nil {
|
|
return 0
|
|
}
|
|
r.last = time.Now()
|
|
s := r.tot
|
|
|
|
var n int
|
|
n, r.err = io.ReadFull(r.r, r.b[:4])
|
|
r.tot += n
|
|
if r.err != nil {
|
|
dl.Debugf("@0x%x: rd uint16:", r.tot, r.err)
|
|
return 0
|
|
}
|
|
|
|
v := uint16(r.b[1]) | uint16(r.b[0])<<8
|
|
|
|
if debug {
|
|
dl.Debugf("@0x%x: rd uint16=%d (0x%04x)", s, v, v)
|
|
}
|
|
return v
|
|
}
|
|
|
|
func (r *Reader) ReadUint32() uint32 {
|
|
if r.err != nil {
|
|
return 0
|
|
}
|
|
r.last = time.Now()
|
|
s := r.tot
|
|
|
|
var n int
|
|
n, r.err = io.ReadFull(r.r, r.b[:4])
|
|
r.tot += n
|
|
if r.err != nil {
|
|
dl.Debugf("@0x%x: rd uint32:", r.tot, r.err)
|
|
return 0
|
|
}
|
|
|
|
v := uint32(r.b[3]) | uint32(r.b[2])<<8 | uint32(r.b[1])<<16 | uint32(r.b[0])<<24
|
|
|
|
if debug {
|
|
dl.Debugf("@0x%x: rd uint32=%d (0x%08x)", s, v, v)
|
|
}
|
|
return v
|
|
}
|
|
|
|
func (r *Reader) ReadUint64() uint64 {
|
|
if r.err != nil {
|
|
return 0
|
|
}
|
|
r.last = time.Now()
|
|
s := r.tot
|
|
|
|
var n int
|
|
n, r.err = io.ReadFull(r.r, r.b[:8])
|
|
r.tot += n
|
|
if r.err != nil {
|
|
dl.Debugf("@0x%x: rd uint64:", r.tot, r.err)
|
|
return 0
|
|
}
|
|
|
|
v := uint64(r.b[7]) | uint64(r.b[6])<<8 | uint64(r.b[5])<<16 | uint64(r.b[4])<<24 |
|
|
uint64(r.b[3])<<32 | uint64(r.b[2])<<40 | uint64(r.b[1])<<48 | uint64(r.b[0])<<56
|
|
|
|
if debug {
|
|
dl.Debugf("@0x%x: rd uint64=%d (0x%016x)", s, v, v)
|
|
}
|
|
return v
|
|
}
|
|
|
|
func (r *Reader) Tot() int {
|
|
return r.tot
|
|
}
|
|
|
|
func (r *Reader) Error() error {
|
|
return r.err
|
|
}
|
|
|
|
func (r *Reader) LastRead() time.Time {
|
|
return r.last
|
|
}
|