55 lines
856 B
C
55 lines
856 B
C
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#include <stdint.h>
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#include <stdlib.h>
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#include "hash.h"
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//-----------------------------------------------------------------------------
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// MurmurHashNeutral2, by Austin Appleby
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// Same as MurmurHash2, but endian- and alignment-neutral.
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uint32_t hash_murmur2(const void * key, int len)
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{
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const unsigned int seed = 0xdeadc0de;
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const unsigned int m = 0x5bd1e995;
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const int r = 24;
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unsigned int h = seed ^ len;
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const unsigned char * data = (const unsigned char *)key;
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while(len >= 4)
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{
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unsigned int k;
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k = data[0];
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k |= data[1] << 8;
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k |= data[2] << 16;
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k |= data[3] << 24;
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k *= m;
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k ^= k >> r;
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k *= m;
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h *= m;
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h ^= k;
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data += 4;
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len -= 4;
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}
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switch(len)
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{
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case 3: h ^= data[2] << 16;
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case 2: h ^= data[1] << 8;
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case 1: h ^= data[0];
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h *= m;
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};
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h ^= h >> 13;
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h *= m;
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h ^= h >> 15;
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return h;
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}
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