2012-09-26 06:37:13 +08:00
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package storage
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import (
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2016-04-06 17:03:32 +08:00
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"encoding/binary"
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2014-07-22 15:24:50 +08:00
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"fmt"
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2014-10-27 02:34:55 +08:00
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2016-04-06 17:03:32 +08:00
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"github.com/klauspost/crc32"
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2012-09-26 06:37:13 +08:00
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)
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var table = crc32.MakeTable(crc32.Castagnoli)
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type CRC uint32
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func NewCRC(b []byte) CRC {
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return CRC(0).Update(b)
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}
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func (c CRC) Update(b []byte) CRC {
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return CRC(crc32.Update(uint32(c), table, b))
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}
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func (c CRC) Value() uint32 {
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return uint32(c>>15|c<<17) + 0xa282ead8
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}
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2014-07-22 15:24:50 +08:00
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func (n *Needle) Etag() string {
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bits := make([]byte, 4)
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2016-04-06 17:03:32 +08:00
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binary.BigEndian.PutUint32(bits, uint32(n.Checksum))
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2014-08-27 01:15:12 +08:00
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return fmt.Sprintf("\"%x\"", bits)
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2014-07-22 15:24:50 +08:00
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}
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