-
Notifications
You must be signed in to change notification settings - Fork 0
/
MurmurHash64A.c
69 lines (56 loc) · 1.47 KB
/
MurmurHash64A.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
#include <stdio.h>
typedef unsigned __int64 uint64_t;
uint64_t MurmurHash64A ( const void * key, int len, uint64_t seed )
{
const uint64_t m = 0xc6a4a7935bd1e995LLU;
const int r = 47;
uint64_t h = seed ^ (len * m);
const uint64_t * data = (const uint64_t *)key;
const uint64_t * end = (len >> 3) + data;
while(data != end)
{
uint64_t k = *data++;
k *= m;
k ^= k >> r;
k *= m;
h ^= k;
h *= m;
}
const unsigned char * data2 = (const unsigned char *)data;
switch(len & 7)
{
case 7: h ^= (uint64_t)(data2[6]) << 48;
case 6: h ^= (uint64_t)(data2[5]) << 40;
case 5: h ^= (uint64_t)(data2[4]) << 32;
case 4: h ^= (uint64_t)(data2[3]) << 24;
case 3: h ^= (uint64_t)(data2[2]) << 16;
case 2: h ^= (uint64_t)(data2[1]) << 8;
case 1: h ^= (uint64_t)(data2[0]);
h *= m;
};
h ^= h >> r;
h *= m;
h ^= h >> r;
return h;
}
/////////////////////////////////////
int main(int argc, char **argv)
{
if (argc > 1) {
char *str = argv[1];
int len = 0;
while (str[++len]) {}
uint64_t hash = MurmurHash64A(str, len, 0);
unsigned int hash_high = (hash >> 32);
unsigned int hash_low = (unsigned int)hash;
// printf("%08x %08x %u %u %llu", hash_high, hash_low, hash_high, hash_low, hash);
if (argc == 2) {
printf("%08x%08x\n", hash_high, hash_low);
} else {
printf("%08x\n", hash_high);
}
} else {
printf("%s", "\nusage:\t MurmurHash64A [string] [8]\n\n");
}
return 0;
}