100 lines
2.1 KiB
Go
100 lines
2.1 KiB
Go
package sarama
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import (
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"encoding/binary"
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"sync"
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)
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// LengthField implements the PushEncoder and PushDecoder interfaces for calculating 4-byte lengths.
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type lengthField struct {
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startOffset int
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length int32
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}
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var lengthFieldPool = sync.Pool{}
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func acquireLengthField() *lengthField {
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val := lengthFieldPool.Get()
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if val != nil {
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return val.(*lengthField)
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}
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return &lengthField{}
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}
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func releaseLengthField(m *lengthField) {
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lengthFieldPool.Put(m)
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}
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func (l *lengthField) decode(pd packetDecoder) error {
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var err error
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l.length, err = pd.getInt32()
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if err != nil {
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return err
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}
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if l.length > int32(pd.remaining()) {
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return ErrInsufficientData
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}
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return nil
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}
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func (l *lengthField) saveOffset(in int) {
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l.startOffset = in
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}
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func (l *lengthField) reserveLength() int {
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return 4
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}
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func (l *lengthField) run(curOffset int, buf []byte) error {
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binary.BigEndian.PutUint32(buf[l.startOffset:], uint32(curOffset-l.startOffset-4))
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return nil
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}
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func (l *lengthField) check(curOffset int, buf []byte) error {
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if int32(curOffset-l.startOffset-4) != l.length {
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return PacketDecodingError{"length field invalid"}
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}
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return nil
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}
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type varintLengthField struct {
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startOffset int
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length int64
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}
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func (l *varintLengthField) decode(pd packetDecoder) error {
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var err error
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l.length, err = pd.getVarint()
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return err
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}
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func (l *varintLengthField) saveOffset(in int) {
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l.startOffset = in
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}
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func (l *varintLengthField) adjustLength(currOffset int) int {
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oldFieldSize := l.reserveLength()
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l.length = int64(currOffset - l.startOffset - oldFieldSize)
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return l.reserveLength() - oldFieldSize
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}
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func (l *varintLengthField) reserveLength() int {
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var tmp [binary.MaxVarintLen64]byte
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return binary.PutVarint(tmp[:], l.length)
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}
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func (l *varintLengthField) run(curOffset int, buf []byte) error {
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binary.PutVarint(buf[l.startOffset:], l.length)
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return nil
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}
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func (l *varintLengthField) check(curOffset int, buf []byte) error {
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if int64(curOffset-l.startOffset-l.reserveLength()) != l.length {
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return PacketDecodingError{"length field invalid"}
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}
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return nil
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}
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