Files
oceanbase/deps/ussl-hook/loop/ussl_ihash_map.c
2023-07-12 05:12:18 +00:00

97 lines
2.9 KiB
C

/**
* Copyright (c) 2021 OceanBase
* OceanBase CE is licensed under Mulan PubL v2.
* You can use this software according to the terms and conditions of the Mulan PubL v2.
* You may obtain a copy of Mulan PubL v2 at:
* http://license.coscl.org.cn/MulanPubL-2.0
* THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
* EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
* MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
* See the Mulan PubL v2 for more details.
*/
#define __ussl_fhmix(h) ({ \
(h) ^= (h) >> 23; \
(h) *= 0x2127599bf4325c37ULL; \
(h) ^= (h) >> 47; })
static uint64_t ussl_fasthash64(const void *buf, size_t len, uint64_t seed)
{
const uint64_t m = 0x880355f21e6d1965ULL;
const uint64_t *pos = (const uint64_t *)buf;
const uint64_t *end = pos + (len / 8);
const unsigned char *pos2;
uint64_t h = seed ^ (len * m);
uint64_t v;
while (pos != end) {
v = *pos++;
h ^= __ussl_fhmix(v);
h *= m;
}
pos2 = (const unsigned char*)pos;
v = 0;
switch (len & 7) {
case 7: v ^= (uint64_t)pos2[6] << 48;
// fall through
case 6: v ^= (uint64_t)pos2[5] << 40;
// fall through
case 5: v ^= (uint64_t)pos2[4] << 32;
// fall through
case 4: v ^= (uint64_t)pos2[3] << 24;
// fall through
case 3: v ^= (uint64_t)pos2[2] << 16;
// fall through
case 2: v ^= (uint64_t)pos2[1] << 8;
// fall through
case 1: v ^= (uint64_t)pos2[0];
h ^= __ussl_fhmix(v);
h *= m;
}
return __ussl_fhmix(h);
}
static uint64_t __ussl_ihash_calc(uint64_t k) { return ussl_fasthash64(&k, sizeof(k), 0); }
static ussl_link_t* __ussl_ihash_locate(ussl_hash_t* map, uint64_t k) { return &map->table[__ussl_ihash_calc(k) % map->capacity]; }
static uint64_t __ussl_ihash_key(ussl_link_t* l) { return *(uint64_t*)(l + 1); }
static ussl_link_t* __ussl_ihash_list_search(ussl_link_t* start, uint64_t k, ussl_link_t** prev) {
ussl_link_t* p = start;
while(p->next != NULL && __ussl_ihash_key(p->next) != k) {
p = p->next;
}
if (NULL != prev) {
*prev = p;
}
return p->next;
}
ussl_link_t* ussl_ihash_insert(ussl_hash_t* map, ussl_link_t* klink) {
ussl_link_t* prev = NULL;
uint64_t k = __ussl_ihash_key(klink);
if(!__ussl_ihash_list_search(__ussl_ihash_locate(map, k), k, &prev)) {
ussl_link_insert(prev, klink);
} else {
klink = NULL;
}
return klink;
}
ussl_link_t* ussl_ihash_del(ussl_hash_t* map, uint64_t k) {
ussl_link_t* ret = NULL;
ussl_link_t* prev = NULL;
if((ret = __ussl_ihash_list_search(__ussl_ihash_locate(map, k), k, &prev))) {
ussl_link_delete(prev);
}
return ret;
}
ussl_link_t* ussl_ihash_get(ussl_hash_t* map, uint64_t k) {
return __ussl_ihash_list_search(__ussl_ihash_locate(map, k), k, NULL);
}
void ussl_hash_init(ussl_hash_t* h, int64_t capacity) {
h->capacity = capacity;
memset(&h->table, 0, sizeof(ussl_link_t) * capacity);
}