#include "Platform.h" #include // for NULL /* By Paul Hsieh (C) 2004, 2005. Covered under the Paul Hsieh derivative license. See: http://www.azillionmonkeys.com/qed/weblicense.html for license details. http://www.azillionmonkeys.com/qed/hash.html */ /* #undef get16bits #if (defined(__GNUC__) && defined(__i386__)) || defined(__WATCOMC__) \ || defined(_MSC_VER) || defined (__BORLANDC__) || defined (__TURBOC__) #define get16bits(d) (*((const uint16_t *) (d))) #endif #if !defined (get16bits) #define get16bits(d) ((((uint32_t)(((const uint8_t *)(d))[1])) << 8)\ +(uint32_t)(((const uint8_t *)(d))[0]) ) #endif */ FORCE_INLINE uint16_t get16bits ( const void * p ) { return *(const uint16_t*)p; } uint32_t SuperFastHash (const signed char * data, int len) { uint32_t hash = 0, tmp; int rem; if (len <= 0 || data == NULL) return 0; rem = len & 3; len >>= 2; /* Main loop */ for (;len > 0; len--) { hash += get16bits (data); tmp = (get16bits (data+2) << 11) ^ hash; hash = (hash << 16) ^ tmp; data += 2*sizeof (uint16_t); hash += hash >> 11; } /* Handle end cases */ switch (rem) { case 3: hash += get16bits (data); hash ^= hash << 16; hash ^= data[sizeof (uint16_t)] << 18; hash += hash >> 11; break; case 2: hash += get16bits (data); hash ^= hash << 11; hash += hash >> 17; break; case 1: hash += *data; hash ^= hash << 10; hash += hash >> 1; } /* Force "avalanching" of final 127 bits */ hash ^= hash << 3; hash += hash >> 5; hash ^= hash << 4; hash += hash >> 17; hash ^= hash << 25; hash += hash >> 6; return hash; } void SuperFastHash ( const void * key, int len, uint32_t /*seed*/, void * out ) { *(uint32_t*)out = SuperFastHash((const signed char*)key,len); }