traefik/vendor/github.com/eapache/go-xerial-snappy/snappy.go
2018-01-10 17:48:04 +01:00

43 lines
870 B
Go

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