Mercurial > hg > nginx
annotate src/core/ngx_murmurhash.c @ 7682:2ab0ecfe5a5f
release-1.19.1 tag
| author | Maxim Dounin <mdounin@mdounin.ru> |
|---|---|
| date | Tue, 07 Jul 2020 18:56:06 +0300 |
| parents | f38647c651a8 |
| children |
| rev | line source |
|---|---|
| 3891 | 1 |
| 2 /* | |
| 3 * Copyright (C) Austin Appleby | |
| 4 */ | |
| 5 | |
| 6 | |
| 7 #include <ngx_config.h> | |
| 8 #include <ngx_core.h> | |
| 9 | |
| 10 | |
| 11 uint32_t | |
| 12 ngx_murmur_hash2(u_char *data, size_t len) | |
| 13 { | |
| 14 uint32_t h, k; | |
| 15 | |
| 16 h = 0 ^ len; | |
| 17 | |
| 18 while (len >= 4) { | |
| 19 k = data[0]; | |
| 20 k |= data[1] << 8; | |
| 21 k |= data[2] << 16; | |
| 22 k |= data[3] << 24; | |
| 23 | |
| 24 k *= 0x5bd1e995; | |
| 25 k ^= k >> 24; | |
| 26 k *= 0x5bd1e995; | |
| 27 | |
| 28 h *= 0x5bd1e995; | |
| 29 h ^= k; | |
| 30 | |
| 31 data += 4; | |
| 32 len -= 4; | |
| 33 } | |
| 34 | |
| 35 switch (len) { | |
| 36 case 3: | |
| 37 h ^= data[2] << 16; | |
|
6994
f38647c651a8
Added missing "fall through" comments (ticket #1259).
Maxim Dounin <mdounin@mdounin.ru>
parents:
3891
diff
changeset
|
38 /* fall through */ |
| 3891 | 39 case 2: |
| 40 h ^= data[1] << 8; | |
|
6994
f38647c651a8
Added missing "fall through" comments (ticket #1259).
Maxim Dounin <mdounin@mdounin.ru>
parents:
3891
diff
changeset
|
41 /* fall through */ |
| 3891 | 42 case 1: |
| 43 h ^= data[0]; | |
| 44 h *= 0x5bd1e995; | |
| 45 } | |
| 46 | |
| 47 h ^= h >> 13; | |
| 48 h *= 0x5bd1e995; | |
| 49 h ^= h >> 15; | |
| 50 | |
| 51 return h; | |
| 52 } |