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#include "fnv.h"
#define FNV_PRIME 0x100000001b3ULL
/*
* 64-bit fnv, but don't require 64-bit multiples of data. Use bytes
* for the last unaligned chunk.
*/
uint64_t fnv(const void *buf, uint32_t len, uint64_t hval)
{
const uint64_t *ptr = buf;
while (len) {
hval *= FNV_PRIME;
if (len >= sizeof(uint64_t)) {
hval ^= (uint64_t) *ptr++;
len -= sizeof(uint64_t);
continue;
} else {
const uint8_t *ptr8 = (const uint8_t *) ptr;
uint64_t val = 0;
int i;
for (i = 0; i < len; i++) {
val <<= 8;
val |= (uint8_t) *ptr8++;
}
hval ^= val;
break;
}
}
return hval;
}
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