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44 lines
870 B
44 lines
870 B
8 years ago
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package snappy
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import (
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"bytes"
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"encoding/binary"
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master "github.com/golang/snappy"
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)
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var xerialHeader = []byte{130, 83, 78, 65, 80, 80, 89, 0}
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// Encode encodes data as snappy with no framing header.
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func Encode(src []byte) []byte {
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return master.Encode(nil, src)
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}
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// Decode decodes snappy data whether it is traditional unframed
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// or includes the xerial framing format.
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func Decode(src []byte) ([]byte, error) {
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if !bytes.Equal(src[:8], xerialHeader) {
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return master.Decode(nil, src)
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}
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var (
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pos = uint32(16)
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max = uint32(len(src))
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dst = make([]byte, 0, len(src))
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chunk []byte
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err error
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)
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for pos < max {
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size := binary.BigEndian.Uint32(src[pos : pos+4])
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pos += 4
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chunk, err = master.Decode(chunk, src[pos:pos+size])
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if err != nil {
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return nil, err
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}
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pos += size
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dst = append(dst, chunk...)
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}
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return dst, nil
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}
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