46 lines
655 B
Go
46 lines
655 B
Go
package cpio
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import (
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"encoding/binary"
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"hash"
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)
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type digest struct {
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sum uint32
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}
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// NewHash returns a new hash.Hash32 computing the SVR4 checksum.
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func NewHash() hash.Hash32 {
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return &digest{}
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}
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func (d *digest) Write(p []byte) (n int, err error) {
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for _, b := range p {
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d.sum += uint32(b & 0xFF)
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}
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return len(p), nil
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}
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func (d *digest) Sum(b []byte) []byte {
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out := [4]byte{}
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binary.LittleEndian.PutUint32(out[:], d.sum)
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return append(b, out[:]...)
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}
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func (d *digest) Sum32() uint32 {
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return d.sum
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}
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func (d *digest) Reset() {
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d.sum = 0
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}
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func (d *digest) Size() int {
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return 4
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}
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func (d *digest) BlockSize() int {
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return 1
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}
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