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- package murmur3
- type bmixer interface {
- bmix(p []byte) (tail []byte)
- Size() (n int)
- reset()
- }
- type digest struct {
- clen int // Digested input cumulative length.
- tail []byte // 0 to Size()-1 bytes view of `buf'.
- buf [16]byte // Expected (but not required) to be Size() large.
- seed uint32 // Seed for initializing the hash.
- bmixer
- }
- func (d *digest) BlockSize() int { return 1 }
- func (d *digest) Write(p []byte) (n int, err error) {
- n = len(p)
- d.clen += n
- if len(d.tail) > 0 {
- // Stick back pending bytes.
- nfree := d.Size() - len(d.tail) // nfree ∈ [1, d.Size()-1].
- if nfree < len(p) {
- // One full block can be formed.
- block := append(d.tail, p[:nfree]...)
- p = p[nfree:]
- _ = d.bmix(block) // No tail.
- } else {
- // Tail's buf is large enough to prevent reallocs.
- p = append(d.tail, p...)
- }
- }
- d.tail = d.bmix(p)
- // Keep own copy of the 0 to Size()-1 pending bytes.
- nn := copy(d.buf[:], d.tail)
- d.tail = d.buf[:nn]
- return n, nil
- }
- func (d *digest) Reset() {
- d.clen = 0
- d.tail = nil
- d.bmixer.reset()
- }
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