blob: 22e033fb42ce0221b010071cd017ca5117e3b37b (
plain)
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
|
#include "stdafx.h"
#ifdef LOG_ENABLED
extern TCHAR tszLogPath[];
void logA(const char *format, ...)
{
FILE *out = _tfopen(tszLogPath, _T("a+"));
if (out) {
va_list args;
va_start(args, format);
vfprintf(out, format, args);
va_end(args);
fclose(out);
}
}
#endif
///////////////////////////////////////////////////////////////////////////////
UINT murmur_hash(const char *str)
{
size_t len = lstrlenA(str);
// 'm' and 'r' are mixing constants generated offline.
// They're not really 'magic', they just happen to work well.
const unsigned int m = 0x5bd1e995;
const int r = 24;
// Initialize the hash to a 'random' value
unsigned int h = (unsigned)len;
// Mix 4 bytes at a time into the hash
const unsigned char *data = (const unsigned char*)str;
while (len >= 4) {
unsigned int k = *(unsigned int*)data;
k *= m;
k ^= k >> r;
k *= m;
h *= m;
h ^= k;
data += 4;
len -= 4;
}
// Handle the last few bytes of the input array
switch(len) {
case 3: h ^= data[2] << 16;
case 2: h ^= data[1] << 8;
case 1: h ^= data[0];
h *= m;
}
// Do a few final mixes of the hash to ensure the last few
// bytes are well-incorporated.
h ^= h >> 13;
h *= m;
h ^= h >> 15;
return h;
}
|