← Back to branch summary

~ci-train-bot/ubuntu-push/ubuntu-push-ubuntu-zesty-2405

« back to all changes in this revision

Viewing changes to external/murmur3/murmur64.go

  • Committer: Samuele Pedroni (Canonical Services Ltd.)
  • Date: 2014-03-24 15:31:42 UTC
  • mto: This revision was merged to the branch mainline in revision 89.
  • Revision ID: samuele.pedroni@canonical.com-20140324153142-a7lrqgefbssbd48e
add murmur3

Show diffs side-by-side

added added

removed removed

Lines of Context:
external/murmur3/murmur64.go
 
1
package murmur3
 
2
 
 
3
import (
 
4
        "hash"
 
5
)
 
6
 
 
7
// Make sure interfaces are correctly implemented.
 
8
var (
 
9
        _ hash.Hash   = new(digest64)
 
10
        _ hash.Hash64 = new(digest64)
 
11
        _ bmixer      = new(digest64)
 
12
)
 
13
 
 
14
// digest64 is half a digest128.
 
15
type digest64 digest128
 
16
 
 
17
func New64() hash.Hash64 {
 
18
        d := (*digest64)(New128().(*digest128))
 
19
        return d
 
20
}
 
21
 
 
22
func (d *digest64) Sum(b []byte) []byte {
 
23
        h1 := d.h1
 
24
        return append(b,
 
25
                byte(h1>>56), byte(h1>>48), byte(h1>>40), byte(h1>>32),
 
26
                byte(h1>>24), byte(h1>>16), byte(h1>>8), byte(h1))
 
27
}
 
28
 
 
29
func (d *digest64) Sum64() uint64 {
 
30
        h1, _ := (*digest128)(d).Sum128()
 
31
        return h1
 
32
}
 
33
 
 
34
// Sum64 returns the MurmurHash3 sum of data. It is equivalent to the
 
35
// following sequence (without the extra burden and the extra allocation):
 
36
//     hasher := New64()
 
37
//     hasher.Write(data)
 
38
//     return hasher.Sum64()
 
39
func Sum64(data []byte) uint64 {
 
40
        d := &digest128{h1: 1, h2: 1}
 
41
        d.tail = d.bmix(data)
 
42
        d.clen = len(data)
 
43
        h1, _ := d.Sum128()
 
44
        return h1
 
45
}