OpenGFW/analyzer/utils/bytebuffer.go

100 lines
2.0 KiB
Go
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2024-01-20 08:45:01 +08:00
package utils
import "bytes"
type ByteBuffer struct {
Buf []byte
}
func (b *ByteBuffer) Append(data []byte) {
b.Buf = append(b.Buf, data...)
}
func (b *ByteBuffer) Len() int {
return len(b.Buf)
}
func (b *ByteBuffer) Index(sep []byte) int {
return bytes.Index(b.Buf, sep)
}
func (b *ByteBuffer) Get(length int, consume bool) (data []byte, ok bool) {
if len(b.Buf) < length {
return nil, false
}
data = b.Buf[:length]
if consume {
b.Buf = b.Buf[length:]
}
return data, true
}
func (b *ByteBuffer) GetString(length int, consume bool) (string, bool) {
data, ok := b.Get(length, consume)
if !ok {
return "", false
}
return string(data), true
}
func (b *ByteBuffer) GetByte(consume bool) (byte, bool) {
data, ok := b.Get(1, consume)
if !ok {
return 0, false
}
return data[0], true
}
func (b *ByteBuffer) GetUint16(littleEndian, consume bool) (uint16, bool) {
data, ok := b.Get(2, consume)
if !ok {
return 0, false
}
if littleEndian {
return uint16(data[0]) | uint16(data[1])<<8, true
}
return uint16(data[1]) | uint16(data[0])<<8, true
}
func (b *ByteBuffer) GetUint32(littleEndian, consume bool) (uint32, bool) {
data, ok := b.Get(4, consume)
if !ok {
return 0, false
}
if littleEndian {
return uint32(data[0]) | uint32(data[1])<<8 | uint32(data[2])<<16 | uint32(data[3])<<24, true
}
return uint32(data[3]) | uint32(data[2])<<8 | uint32(data[1])<<16 | uint32(data[0])<<24, true
}
func (b *ByteBuffer) GetUntil(sep []byte, includeSep, consume bool) (data []byte, ok bool) {
index := b.Index(sep)
if index == -1 {
return nil, false
}
if includeSep {
index += len(sep)
}
return b.Get(index, consume)
}
func (b *ByteBuffer) GetSubBuffer(length int, consume bool) (sub *ByteBuffer, ok bool) {
data, ok := b.Get(length, consume)
if !ok {
return nil, false
}
return &ByteBuffer{Buf: data}, true
}
func (b *ByteBuffer) Skip(length int) bool {
if len(b.Buf) < length {
return false
}
b.Buf = b.Buf[length:]
return true
}
func (b *ByteBuffer) Reset() {
b.Buf = nil
}