Sha256: 8b669dc3f10b6a8a0c256b5155e8fa1985bfea5e321f59a910702a54251708d2
Contents?: true
Size: 2 KB
Versions: 6
Compression:
Stored size: 2 KB
Contents
//-----------------------------------------------------------------------------
// MurmurHash2 was written by Austin Appleby, and is placed in the public
// domain. The author hereby disclaims copyright to this source code.
//-----------------------------------------------------------------------------
// LibSass only needs MurmurHash2, so we made this header only
//-----------------------------------------------------------------------------
#ifndef _MURMURHASH2_H_
#define _MURMURHASH2_H_
//-----------------------------------------------------------------------------
// Platform-specific functions and macros
// Microsoft Visual Studio
#if defined(_MSC_VER) && (_MSC_VER < 1600)
typedef unsigned char uint8_t;
typedef unsigned int uint32_t;
typedef unsigned __int64 uint64_t;
// Other compilers
#else // defined(_MSC_VER)
#include <stdint.h>
#endif // !defined(_MSC_VER)
//-----------------------------------------------------------------------------
inline uint32_t MurmurHash2 ( const void * key, int len, uint32_t seed )
{
// 'm' and 'r' are mixing constants generated offline.
// They're not really 'magic', they just happen to work well.
const uint32_t m = 0x5bd1e995;
const int r = 24;
// Initialize the hash to a 'random' value
uint32_t h = seed ^ len;
// Mix 4 bytes at a time into the hash
const unsigned char * data = (const unsigned char *)key;
while(len >= 4)
{
uint32_t k = *(uint32_t*)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;
/* fall through */
case 2:
h ^= data[1] << 8;
/* fall through */
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;
}
//-----------------------------------------------------------------------------
#endif // _MURMURHASH2_H_
Version data entries
6 entries across 5 versions & 4 rubygems