50 lines
832 B
Go
50 lines
832 B
Go
package wal
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import (
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"bufio"
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"encoding/binary"
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"hash"
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"io"
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"github.com/coreos/etcd/crc"
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"github.com/coreos/etcd/wal/walpb"
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)
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type encoder struct {
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bw *bufio.Writer
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crc hash.Hash32
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}
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func newEncoder(w io.Writer, prevCrc uint32) *encoder {
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return &encoder{
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bw: bufio.NewWriter(w),
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crc: crc.New(prevCrc, crcTable),
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}
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}
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func (e *encoder) encode(rec *walpb.Record) error {
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e.crc.Write(rec.Data)
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rec.Crc = e.crc.Sum32()
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data, err := rec.Marshal()
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if err != nil {
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return err
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}
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if err := writeInt64(e.bw, int64(len(data))); err != nil {
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return err
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}
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_, err = e.bw.Write(data)
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return err
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}
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func (e *encoder) flush() error {
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return e.bw.Flush()
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}
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func (e *encoder) buffered() int {
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return e.bw.Buffered()
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}
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func writeInt64(w io.Writer, n int64) error {
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return binary.Write(w, binary.LittleEndian, n)
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}
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