87 lines
1.2 KiB
C
87 lines
1.2 KiB
C
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/*
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* The code is based on the code by Austin Appleby,
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* released to the public domain.
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*/
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#include <nxt_main.h>
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uint32_t
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nxt_murmur_hash2(const void *data, size_t len)
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{
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uint32_t h, k;
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const u_char *p;
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const uint32_t m = 0x5BD1E995;
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p = data;
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h = 0 ^ (uint32_t) len;
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while (len >= 4) {
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k = p[0];
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k |= p[1] << 8;
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k |= p[2] << 16;
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k |= p[3] << 24;
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k *= m;
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k ^= k >> 24;
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k *= m;
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h *= m;
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h ^= k;
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p += 4;
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len -= 4;
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}
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switch (len) {
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case 3:
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h ^= p[2] << 16;
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/* Fall through. */
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case 2:
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h ^= p[1] << 8;
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/* Fall through. */
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case 1:
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h ^= p[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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/* The MurmurHash2 for fixed 4 byte length. */
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uint32_t
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nxt_murmur_hash2_uint32(const void *data)
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{
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uint32_t h, k;
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const u_char *p;
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const uint32_t m = 0x5BD1E995;
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p = data;
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k = p[0];
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k |= p[1] << 8;
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k |= p[2] << 16;
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k |= p[3] << 24;
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k *= m;
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k ^= k >> 24;
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k *= m;
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h = 0 ^ 4;
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h *= m;
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h ^= k;
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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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