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/*
* The code is based on the code by Austin Appleby,
* released to the public domain.
*/
#include <njs_main.h>
uint32_t
njs_murmur_hash2(const void *data, size_t len)
{
uint32_t h, k;
const u_char *p;
const uint32_t m = 0x5bd1e995;
p = data;
h = 0 ^ (uint32_t) len;
while (len >= 4) {
k = p[0];
k |= p[1] << 8;
k |= p[2] << 16;
k |= p[3] << 24;
k *= m;
k ^= k >> 24;
k *= m;
h *= m;
h ^= k;
p += 4;
len -= 4;
}
switch (len) {
case 3:
h ^= p[2] << 16;
/* Fall through. */
case 2:
h ^= p[1] << 8;
/* Fall through. */
case 1:
h ^= p[0];
h *= m;
}
h ^= h >> 13;
h *= m;
h ^= h >> 15;
return h;
}
/* The MurmurHash2 for fixed 4 byte length. */
uint32_t
njs_murmur_hash2_uint32(const void *data)
{
uint32_t h, k;
const u_char *p;
const uint32_t m = 0x5bd1e995;
p = data;
k = p[0];
k |= p[1] << 8;
k |= p[2] << 16;
k |= p[3] << 24;
k *= m;
k ^= k >> 24;
k *= m;
h = 0 ^ 4;
h *= m;
h ^= k;
h ^= h >> 13;
h *= m;
h ^= h >> 15;
return h;
}
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