erl_hash

#include "fnv.h"

static uint64_t FNV_64_INIT = UINT64_C(0xcbf29ce484222325);
static uint64_t FNV_64_PRIME = UINT64_C(0x100000001b3);
static uint32_t FNV_32_INIT = 2166136261UL;
static uint32_t FNV_32_PRIME = 16777619;

uint32_t hash_fnv1_64(const unsigned char *key, size_t key_length)
{
    uint64_t hash = FNV_64_INIT;
    size_t x;

    for (x = 0; x < key_length; x++)
    {
        hash *= FNV_64_PRIME;
        hash ^= (uint64_t)key[x];
    }

    return (uint32_t)hash;
}

uint32_t hash_fnv1a_64(const unsigned char *key, size_t key_length)
{
    uint32_t hash = (uint32_t) FNV_64_INIT;
    size_t x;

    for (x = 0; x < key_length; x++)
    {
        uint32_t val = (uint32_t)key[x];
        hash ^= val;
        hash *= (uint32_t) FNV_64_PRIME;
    }

    return hash;
}

uint32_t hash_fnv1_32(const unsigned char *key, size_t key_length)
{
    uint32_t hash = FNV_32_INIT;
    size_t x;

    for (x = 0; x < key_length; x++)
    {
        uint32_t val = (uint32_t)key[x];
        hash *= FNV_32_PRIME;
        hash ^= val;
    }

    return hash;
}

uint32_t hash_fnv1a_32(const unsigned char *key, size_t key_length)
{
    uint32_t hash = FNV_32_INIT;
    size_t x;

    for (x= 0; x < key_length; x++)
    {
        uint32_t val = (uint32_t)key[x];
        hash ^= val;
        hash *= FNV_32_PRIME;
    }

    return hash;
}