murmur64.go

package murmur3

// Digest64 is half a digest128.
type Digest64 Digest128

// New64 returns a 64-bit hasher
func New64() Digest64 { return New64WithSeed(0) }

// New64WithSeed returns a 64-bit hasher set with explicit seed value
func New64WithSeed(seed uint32) Digest64 {
	return Digest64(New128WithSeed(seed))
}

func (d Digest64) Size() int {
	return 8
}

func (d Digest64) Sum(b []byte) []byte {
	h1 := d.Sum64()
	return append(b,
		byte(h1>>56), byte(h1>>48), byte(h1>>40), byte(h1>>32),
		byte(h1>>24), byte(h1>>16), byte(h1>>8), byte(h1))
}

func (d Digest64) Sum64() uint64 {
	h1, _ := Digest128(d).Sum128()
	return h1
}

func (d Digest64) Write(p []byte) Digest64 {
	return Digest64(Digest128(d).Write(p))
}

// Sum64 returns the MurmurHash3 sum of data. It is equivalent to the
// following sequence (without the extra burden and the extra allocation):
//     hasher := New64()
//     hasher.Write(data)
//     return hasher.Sum64()
func Sum64(data []byte) uint64 { return Sum64WithSeed(data, 0) }

// Sum64WithSeed returns the MurmurHash3 sum of data. It is equivalent to the
// following sequence (without the extra burden and the extra allocation):
//     hasher := New64WithSeed(seed)
//     hasher.Write(data)
//     return hasher.Sum64()
func Sum64WithSeed(data []byte, seed uint32) uint64 {
	return New64WithSeed(seed).Write(data).Sum64()
}