seaweedfs/weed/storage/needle/crc.go
Chris Lu 9b3109a5d8 filer: processing all response headers, no pass through to volume server
* filer calculate MD5 etag
* filer handle response headers, instread of pass it to volume servers
2020-03-08 15:42:44 -07:00

32 lines
529 B
Go

package needle
import (
"fmt"
"github.com/klauspost/crc32"
"github.com/chrislusf/seaweedfs/weed/util"
)
var table = crc32.MakeTable(crc32.Castagnoli)
type CRC uint32
func NewCRC(b []byte) CRC {
return CRC(0).Update(b)
}
func (c CRC) Update(b []byte) CRC {
return CRC(crc32.Update(uint32(c), table, b))
}
func (c CRC) Value() uint32 {
return uint32(c>>15|c<<17) + 0xa282ead8
}
func (n *Needle) Etag() string {
bits := make([]byte, 4)
util.Uint32toBytes(bits, uint32(n.Checksum))
return fmt.Sprintf("%x", bits)
}