comparison: ucx/hash_key.c
ucx/hash_key.c
- changeset 852
- 83fdf679df99
- parent 747
- efbd59642577
equal
deleted
inserted
replaced
| 850:bbe2925eb590 | 852:83fdf679df99 |
|---|---|
| 28 | 28 |
| 29 #include "cx/hash_key.h" | 29 #include "cx/hash_key.h" |
| 30 #include <string.h> | 30 #include <string.h> |
| 31 | 31 |
| 32 void cx_hash_murmur(CxHashKey *key) { | 32 void cx_hash_murmur(CxHashKey *key) { |
| 33 unsigned char const *data = key->data; | 33 const unsigned char *data = key->data; |
| 34 if (data == NULL) { | 34 if (data == NULL) { |
| 35 // extension: special value for NULL | 35 // extension: special value for NULL |
| 36 key->hash = 1574210520u; | 36 key->hash = 1574210520u; |
| 37 return; | 37 return; |
| 38 } | 38 } |
| 39 size_t len = key->len; | 39 size_t len = key->len; |
| 40 | 40 |
| 41 unsigned m = 0x5bd1e995; | 41 unsigned m = 0x5bd1e995; |
| 42 unsigned r = 24; | 42 unsigned r = 24; |
| 43 unsigned h = 25 ^ len; | 43 unsigned h = 25 ^ (unsigned) len; |
| 44 unsigned i = 0; | 44 unsigned i = 0; |
| 45 while (len >= 4) { | 45 while (len >= 4) { |
| 46 unsigned k = data[i + 0] & 0xFF; | 46 unsigned k = data[i + 0] & 0xFF; |
| 47 k |= (data[i + 1] & 0xFF) << 8; | 47 k |= (data[i + 1] & 0xFF) << 8; |
| 48 k |= (data[i + 2] & 0xFF) << 16; | 48 k |= (data[i + 2] & 0xFF) << 16; |
| 79 h ^= h >> 15; | 79 h ^= h >> 15; |
| 80 | 80 |
| 81 key->hash = h; | 81 key->hash = h; |
| 82 } | 82 } |
| 83 | 83 |
| 84 CxHashKey cx_hash_key_str(char const *str) { | 84 CxHashKey cx_hash_key_str(const char *str) { |
| 85 CxHashKey key; | 85 CxHashKey key; |
| 86 key.data = str; | 86 key.data = str; |
| 87 key.len = str == NULL ? 0 : strlen(str); | 87 key.len = str == NULL ? 0 : strlen(str); |
| 88 cx_hash_murmur(&key); | 88 cx_hash_murmur(&key); |
| 89 return key; | 89 return key; |
| 90 } | 90 } |
| 91 | 91 |
| 92 CxHashKey cx_hash_key_bytes( | 92 CxHashKey cx_hash_key_bytes( |
| 93 unsigned char const *bytes, | 93 const unsigned char *bytes, |
| 94 size_t len | 94 size_t len |
| 95 ) { | 95 ) { |
| 96 CxHashKey key; | 96 CxHashKey key; |
| 97 key.data = bytes; | 97 key.data = bytes; |
| 98 key.len = len; | 98 key.len = len; |
| 99 cx_hash_murmur(&key); | 99 cx_hash_murmur(&key); |
| 100 return key; | 100 return key; |
| 101 } | 101 } |
| 102 | 102 |
| 103 CxHashKey cx_hash_key( | 103 CxHashKey cx_hash_key( |
| 104 void const *obj, | 104 const void *obj, |
| 105 size_t len | 105 size_t len |
| 106 ) { | 106 ) { |
| 107 CxHashKey key; | 107 CxHashKey key; |
| 108 key.data = obj; | 108 key.data = obj; |
| 109 key.len = len; | 109 key.len = len; |
