curl/lib/hash.c
2002-01-18 10:36:25 +00:00

286 lines
6.7 KiB
C

/*****************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 2001, Daniel Stenberg, <daniel@haxx.se>, et al
*
* In order to be useful for every potential user, curl and libcurl are
* dual-licensed under the MPL and the MIT/X-derivate licenses.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the MPL or the MIT/X-derivate
* licenses. You may pick one of these licenses.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* $Id$
*****************************************************************************/
#include "setup.h"
#include <string.h>
#include "hash.h"
#include "llist.h"
#ifdef MALLOCDEBUG
/* this must be the last include file */
#include "memdebug.h"
#endif
static unsigned long
curl_hash_str(const char *key, unsigned int key_length)
{
register unsigned long h = 0;
register unsigned long g;
register char *p = (char *) key;
register char *end = (char *) key + key_length;
while (p < end) {
h = (h << 4) + *p++;
if ((g = (h & 0xF0000000))) {
h = h ^ (g >> 24);
h = h ^ g;
}
}
return h;
}
static unsigned long
curl_hash_num(unsigned long key)
{
key += ~(key << 15);
key ^= (key >> 10);
key += (key << 3);
key ^= (key >> 6);
key += (key << 11);
key ^= (key >> 16);
return key;
}
static void
hash_element_dtor(void *u, void *ele)
{
curl_hash_element *e = (curl_hash_element *) ele;
curl_hash *h = (curl_hash *) u;
if (e->key.type == CURL_HASH_KEY_IS_STRING) {
free(e->key.value.str.val);
}
h->dtor(e->ptr);
free(e);
e = NULL;
}
void
curl_hash_init(curl_hash *h, int slots, curl_hash_dtor dtor)
{
int i;
h->dtor = dtor;
h->size = 0;
h->slots = slots;
h->table = (curl_llist **) malloc(slots * sizeof(curl_llist *));
for (i = 0; i < h->slots; ++i) {
h->table[i] = curl_llist_alloc((curl_llist_dtor) hash_element_dtor);
}
}
curl_hash *
curl_hash_alloc(int slots, curl_hash_dtor dtor)
{
curl_hash *h;
h = (curl_hash *)malloc(sizeof(curl_hash));
if(NULL == h)
return NULL;
curl_hash_init(h, slots, dtor);
return h;
}
#define FIND_SLOT(__h, __s_key, __s_key_len, __n_key) \
((__s_key ? curl_hash_str(__s_key, __s_key_len) : curl_hash_num(__n_key)) % (__h)->slots)
#define KEY_CREATE(__k, __s_key, __s_key_len, __n_key, __dup) \
if (__s_key) { \
if (__dup) { \
(__k)->value.str.val = (char *) malloc(__s_key_len); \
memcpy((__k)->value.str.val, __s_key, __s_key_len); \
} else { \
(__k)->value.str.val = __s_key; \
} \
(__k)->value.str.len = __s_key_len; \
(__k)->type = CURL_HASH_KEY_IS_STRING; \
} else { \
(__k)->value.num = __n_key; \
(__k)->type = CURL_HASH_KEY_IS_NUM; \
}
#define MIN(a, b) (a > b ? b : a)
static int
curl_hash_key_compare(curl_hash_key *key1, curl_hash_key *key2)
{
if (key1->type == CURL_HASH_KEY_IS_NUM) {
if (key2->type == CURL_HASH_KEY_IS_STRING)
return 0;
if (key1->value.num == key2->value.num)
return 1;
} else {
if (key2->type == CURL_HASH_KEY_IS_NUM)
return 0;
if (memcmp(key1->value.str.val, key2->value.str.val,
MIN(key1->value.str.len, key2->value.str.len)) == 0)
return 1;
}
return 0;
}
int
curl_hash_add_or_update(curl_hash *h, char *str_key, unsigned int str_key_len,
unsigned long num_key, const void *p)
{
curl_hash_element *e;
curl_hash_key tmp;
curl_llist *l;
curl_llist_element *le;
int slot;
slot = FIND_SLOT(h, str_key, str_key_len, num_key);
l = h->table[slot];
KEY_CREATE(&tmp, str_key, str_key_len, num_key, 0);
for (le = CURL_LLIST_HEAD(l); le != NULL; le = CURL_LLIST_NEXT(le)) {
if (curl_hash_key_compare(&tmp, &((curl_hash_element *) CURL_LLIST_VALP(le))->key)) {
curl_hash_element *to_update = CURL_LLIST_VALP(le);
h->dtor(to_update->ptr);
to_update->ptr = (void *) p;
return 1;
}
}
e = (curl_hash_element *) malloc(sizeof(curl_hash_element));
KEY_CREATE(&e->key, str_key, str_key_len, num_key, 1);
e->ptr = (void *) p;
if (curl_llist_insert_next(l, CURL_LLIST_TAIL(l), e)) {
++h->size;
return 1;
} else {
return 0;
}
}
int
curl_hash_extended_delete(curl_hash *h, char *str_key, unsigned int str_key_len,
unsigned long num_key)
{
curl_llist *l;
curl_llist_element *le;
curl_hash_key tmp;
int slot;
slot = FIND_SLOT(h, str_key, str_key_len, num_key);
l = h->table[slot];
KEY_CREATE(&tmp, str_key, str_key_len, num_key, 0);
for (le = CURL_LLIST_HEAD(l); le != NULL; le = CURL_LLIST_NEXT(le)) {
if (curl_hash_key_compare(&tmp, &((curl_hash_element *) CURL_LLIST_VALP(le))->key)) {
curl_llist_remove(l, le, (void *) h);
--h->size;
return 1;
}
}
return 0;
}
int
curl_hash_extended_find(curl_hash *h, char *str_key, unsigned int str_key_len,
unsigned long num_key, void **p)
{
curl_llist *l;
curl_llist_element *le;
curl_hash_key tmp;
int slot;
slot = FIND_SLOT(h, str_key, str_key_len, num_key);
l = h->table[slot];
KEY_CREATE(&tmp, str_key, str_key_len, num_key, 0);
for (le = CURL_LLIST_HEAD(l); le != NULL; le = CURL_LLIST_NEXT(le)) {
if (curl_hash_key_compare(&tmp, &((curl_hash_element *) CURL_LLIST_VALP(le))->key)) {
*p = ((curl_hash_element *) CURL_LLIST_VALP(le))->ptr;
return 1;
}
}
return 0;
}
void
curl_hash_apply(curl_hash *h, void *user, void (*cb)(void *, curl_hash_element *))
{
curl_llist_element *le;
int i;
for (i = 0; i < h->slots; ++i) {
for (le = CURL_LLIST_HEAD(h->table[i]); le != NULL; le = CURL_LLIST_NEXT(le)) {
cb(user, (curl_hash_element *) CURL_LLIST_VALP(le));
}
}
}
void
curl_hash_clean(curl_hash *h)
{
int i;
for (i = 0; i < h->slots; ++i) {
curl_llist_destroy(h->table[i], (void *) h);
}
free(h->table);
h->table = NULL;
}
size_t
curl_hash_count(curl_hash *h)
{
return h->size;
}
void
curl_hash_destroy(curl_hash *h)
{
if (!h) {
return;
}
curl_hash_clean(h);
free(h);
h = NULL;
}
/*
* local variables:
* eval: (load-file "../curl-mode.el")
* end:
* vim600: fdm=marker
* vim: et sw=2 ts=2 sts=2 tw=78
*/