feat(query): add hll function

This commit is contained in:
Ganlin Zhao 2022-05-17 10:34:59 +08:00
parent 67e93ef90c
commit 143c50dde3
2 changed files with 63 additions and 26 deletions

View File

@ -40,6 +40,7 @@ typedef void (*_hash_free_fn_t)(void *);
*/
uint32_t MurmurHash3_32(const char *key, uint32_t len);
uint64_t MurmurHash3_64(const char *key, uint32_t len);
/**
*
* @param key

View File

@ -78,6 +78,42 @@ uint32_t MurmurHash3_32(const char *key, uint32_t len) {
return h1;
}
uint64_t MurmurHash3_64(const char *key, uint32_t len) {
const uint64_t m = 0x87c37b91114253d5;
const int r = 47;
uint32_t seed = 0x12345678;
uint64_t h = seed ^ (len * m);
const uint8_t *data = (const uint8_t *)key;
const uint8_t *end = data + (len-(len&7));
while(data != end) {
uint64_t k = *((uint64_t*)data);
k *= m;
k ^= k >> r;
k *= m;
h ^= k;
h *= m;
data += 8;
}
switch(len & 7) {
case 7: h ^= (uint64_t)data[6] << 48; /* fall-thru */
case 6: h ^= (uint64_t)data[5] << 40; /* fall-thru */
case 5: h ^= (uint64_t)data[4] << 32; /* fall-thru */
case 4: h ^= (uint64_t)data[3] << 24; /* fall-thru */
case 3: h ^= (uint64_t)data[2] << 16; /* fall-thru */
case 2: h ^= (uint64_t)data[1] << 8; /* fall-thru */
case 1: h ^= (uint64_t)data[0];
h *= m; /* fall-thru */
};
h ^= h >> r;
h *= m;
h ^= h >> r;
return h;
}
uint32_t taosIntHash_32(const char *key, uint32_t UNUSED_PARAM(len)) { return *(uint32_t *)key; }
uint32_t taosIntHash_16(const char *key, uint32_t UNUSED_PARAM(len)) { return *(uint16_t *)key; }
uint32_t taosIntHash_8(const char *key, uint32_t UNUSED_PARAM(len)) { return *(uint8_t *)key; }