5 Author: Pekka Riikonen <priikone@poseidon.pspt.fi>
7 Copyright (C) 2000 - 2001 Pekka Riikonen
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
22 #include "silcincludes.h"
23 #include "silcidcache.h"
25 /* Static prototypes */
26 static void silc_idcache_destructor(void *key, void *context,
28 static SilcIDCacheList silc_idcache_list_alloc();
29 static void silc_idcache_list_add(SilcIDCacheList list,
30 SilcIDCacheEntry cache);
35 This is context for the ID cache system. This includes all the cache
36 entries and other internal data. This is read-only object and not
37 visible outside this cache system.
39 Fields are as follows:
41 SilcHashTable id_table
43 Hash table using the ID as the key.
45 SilcHashTable name_table
47 Hash table using the name as the key.
49 SilcHashTable context_table
51 Hash table using the context as the key.
53 SilcIDCacheDestructor destructor
55 Destructor callback that is called when an cache entry expires or is
56 purged from the ID cache. The application must not free cache entry
57 because the library will do it automatically. The appliation, however,
58 is responsible of freeing any data in the entry.
62 Indicates the type of the ID's this cache holds.
65 struct SilcIDCacheStruct {
66 SilcHashTable id_table;
67 SilcHashTable name_table;
68 SilcHashTable context_table;
69 SilcIDCacheDestructor destructor;
76 This is returned when searching the cache. Enumeration functions are
77 provided to traverse the list; actually this is used as table not as
80 By default the found cache entries are saved into the static cache
81 table to provide access without reallocation. However, if the static
82 table is full, rest of the cache entries are dynamically allocated
83 into `cache_dyn' table. Traversing functions automatically handles
87 struct SilcIDCacheListStruct {
88 SilcIDCacheEntry cache[128];
89 SilcIDCacheEntry *cache_dyn;
90 SilcUInt32 cache_dyn_count;
91 SilcUInt32 cache_count;
96 /* Allocates new ID cache object. The initial amount of allocated entries
97 can be sent as argument. If `count' is 0 the system uses default values.
98 The `id_type' defines the types of the ID's that will be saved to the
101 SilcIDCache silc_idcache_alloc(SilcUInt32 count, SilcIdType id_type,
102 SilcIDCacheDestructor destructor)
106 SILC_LOG_DEBUG(("Allocating new cache"));
108 cache = silc_calloc(1, sizeof(*cache));
111 cache->id_table = silc_hash_table_alloc(count, silc_hash_id,
112 (void *)(SilcUInt32)id_type,
113 silc_hash_id_compare,
114 (void *)(SilcUInt32)id_type,
115 silc_idcache_destructor, NULL, TRUE);
116 cache->name_table = silc_hash_table_alloc(count, silc_hash_string, NULL,
117 silc_hash_string_compare, NULL,
119 cache->context_table = silc_hash_table_alloc(count, silc_hash_ptr, NULL,
120 NULL, NULL, NULL, NULL, TRUE);
121 cache->destructor = destructor;
122 cache->type = id_type;
124 if (!cache->id_table || !cache->name_table || !cache->context_table) {
126 silc_hash_table_free(cache->id_table);
127 if (cache->name_table)
128 silc_hash_table_free(cache->name_table);
129 if (cache->context_table)
130 silc_hash_table_free(cache->context_table);
138 /* Frees ID cache object and cache entries */
140 void silc_idcache_free(SilcIDCache cache)
143 silc_hash_table_free(cache->id_table);
144 silc_hash_table_free(cache->name_table);
145 silc_hash_table_free(cache->context_table);
150 /* Add new entry to the cache. Returns TRUE if the entry was added and
151 FALSE if it could not be added. The `name' is the name associated with
152 the ID, the `id' the actual ID and the `context' a used specific context.
153 If the `expire' is TRUE the entry expires in default time and if FALSE
154 the entry never expires from the cache. */
156 bool silc_idcache_add(SilcIDCache cache, char *name, void *id,
157 void *context, int expire, SilcIDCacheEntry *ret)
161 SILC_LOG_DEBUG(("Adding cache entry"));
163 /* Allocate new cache entry */
164 c = silc_calloc(1, sizeof(*c));
170 c->context = context;
172 /* Add the new entry to the hash tables */
175 silc_hash_table_add(cache->id_table, id, c);
177 silc_hash_table_add(cache->name_table, name, c);
179 silc_hash_table_add(cache->context_table, context, c);
187 /* Destructor for the ID Cache entry */
189 static void silc_idcache_destructor(void *key, void *context,
195 /* Delete cache entry from cache. */
197 bool silc_idcache_del(SilcIDCache cache, SilcIDCacheEntry old)
201 SILC_LOG_DEBUG(("Deleting cache entry"));
204 ret = silc_hash_table_del_by_context(cache->name_table, old->name, old);
206 ret = silc_hash_table_del(cache->context_table, old->context);
208 ret = silc_hash_table_del(cache->id_table, old->id);
215 /* Deletes ID cache entry by ID. */
217 bool silc_idcache_del_by_id(SilcIDCache cache, void *id)
221 if (!silc_hash_table_find(cache->id_table, id, NULL, (void *)&c))
224 return silc_idcache_del(cache, c);
227 /* Same as above but with specific hash and comparison functions. If the
228 functions are NULL then default values are used. */
230 bool silc_idcache_del_by_id_ext(SilcIDCache cache, void *id,
231 SilcHashFunction hash,
233 SilcHashCompare compare,
234 void *compare_context)
239 SILC_LOG_DEBUG(("Deleting cache entry"));
241 if (!silc_hash_table_find_ext(cache->id_table, id, NULL, (void *)&c,
242 hash, hash_context, compare,
247 ret = silc_hash_table_del_by_context(cache->name_table, c->name, c);
249 ret = silc_hash_table_del(cache->context_table, c->context);
251 ret = silc_hash_table_del_ext(cache->id_table, c->id, hash,
252 hash_context, compare, compare_context,
258 /* Deletes ID cache entry by context. */
260 bool silc_idcache_del_by_context(SilcIDCache cache, void *context)
265 SILC_LOG_DEBUG(("Deleting cache entry"));
267 if (!silc_hash_table_find(cache->context_table, context, NULL, (void *)&c))
271 ret = silc_hash_table_del_by_context(cache->name_table, c->name, c);
273 ret = silc_hash_table_del(cache->context_table, c->context);
275 ret = silc_hash_table_del_by_context(cache->id_table, c->id, c);
282 /* Deletes all ID entries from cache. Free's memory as well. */
284 bool silc_idcache_del_all(SilcIDCache cache)
286 silc_hash_table_free(cache->id_table);
287 silc_hash_table_free(cache->name_table);
288 silc_hash_table_free(cache->context_table);
293 static void silc_idcache_destructor_dummy(void *key, void *context,
296 /* Dummy - nothing */
299 /* Foreach callback fro silc_idcache_purge. */
301 static void silc_idcache_purge_foreach(void *key, void *context,
304 SilcIDCache cache = (SilcIDCache)user_context;
305 SilcUInt32 curtime = time(NULL);
306 SilcIDCacheEntry c = (SilcIDCacheEntry)context;
311 if (c->expire && c->expire < curtime) {
312 /* Remove the entry from the hash tables */
314 silc_hash_table_del_by_context(cache->name_table, c->name, c);
316 silc_hash_table_del(cache->context_table, c->context);
318 silc_hash_table_del_by_context_ext(cache->id_table, c->id, c,
319 NULL, NULL, NULL, NULL,
320 silc_idcache_destructor_dummy, NULL);
322 /* Call the destructor */
323 if (cache->destructor)
324 cache->destructor(cache, c);
326 /* Free the entry, it has been deleted from the hash tables */
331 /* Purges the cache by removing expired cache entires. Note that this
332 may be very slow operation. */
334 bool silc_idcache_purge(SilcIDCache cache)
336 silc_hash_table_foreach(cache->id_table, silc_idcache_purge_foreach, cache);
340 /* Purges the specific entry by context. */
342 bool silc_idcache_purge_by_context(SilcIDCache cache, void *context)
347 if (!silc_hash_table_find(cache->context_table, context, NULL,
351 /* Remove the entry from the hash tables */
353 ret = silc_hash_table_del_by_context(cache->name_table, c->name, c);
355 ret = silc_hash_table_del(cache->context_table, c->context);
358 silc_hash_table_del_by_context_ext(cache->id_table, c->id, c,
359 NULL, NULL, NULL, NULL,
360 silc_idcache_destructor_dummy, NULL);
362 /* Call the destructor */
363 if (cache->destructor)
364 cache->destructor(cache, c);
366 /* Free the entry, it has been deleted from the hash tables */
372 /* Callback that is called by the hash table routine when traversing
373 entrys in the hash table. */
375 static void silc_idcache_get_all_foreach(void *key, void *context,
378 SilcIDCacheList list = (SilcIDCacheList)user_context;
381 silc_idcache_list_add(list, (SilcIDCacheEntry)context);
384 /* Returns all cache entrys from the ID cache to the `ret' ID Cache List. */
386 bool silc_idcache_get_all(SilcIDCache cache, SilcIDCacheList *ret)
388 SilcIDCacheList list;
393 list = silc_idcache_list_alloc();
396 silc_hash_table_foreach(cache->id_table, silc_idcache_get_all_foreach, list);
398 if (silc_idcache_list_count(list) == 0) {
399 silc_idcache_list_free(list);
408 /* Find ID Cache entry by ID. May return multiple entries. */
410 bool silc_idcache_find_by_id(SilcIDCache cache, void *id,
411 SilcIDCacheList *ret)
413 SilcIDCacheList list;
415 list = silc_idcache_list_alloc();
422 silc_hash_table_find_foreach(cache->id_table, id,
423 silc_idcache_get_all_foreach, list);
425 if (silc_idcache_list_count(list) == 0) {
426 silc_idcache_list_free(list);
435 /* Find specific ID with specific hash function and comparison functions.
436 If `hash' is NULL then the default hash funtion is used and if `compare'
437 is NULL default comparison function is used. */
439 bool silc_idcache_find_by_id_one_ext(SilcIDCache cache, void *id,
440 SilcHashFunction hash,
442 SilcHashCompare compare,
443 void *compare_context,
444 SilcIDCacheEntry *ret)
446 return silc_hash_table_find_ext(cache->id_table, id, NULL, (void *)ret,
447 hash, hash_context, compare,
451 /* Find one specific ID entry. */
453 bool silc_idcache_find_by_id_one(SilcIDCache cache, void *id,
454 SilcIDCacheEntry *ret)
456 return silc_hash_table_find(cache->id_table, id, NULL, (void *)ret);
459 /* Finds cache entry by context. */
461 bool silc_idcache_find_by_context(SilcIDCache cache, void *context,
462 SilcIDCacheEntry *ret)
464 return silc_hash_table_find(cache->context_table, context, NULL,
468 /* Find ID Cache entry by name. Returns list of cache entries. */
470 bool silc_idcache_find_by_name(SilcIDCache cache, char *name,
471 SilcIDCacheList *ret)
473 SilcIDCacheList list;
475 list = silc_idcache_list_alloc();
482 silc_hash_table_find_foreach(cache->name_table, name,
483 silc_idcache_get_all_foreach, list);
485 if (silc_idcache_list_count(list) == 0) {
486 silc_idcache_list_free(list);
495 /* Find ID Cache entry by name. Returns one cache entry. */
497 bool silc_idcache_find_by_name_one(SilcIDCache cache, char *name,
498 SilcIDCacheEntry *ret)
500 if (!silc_hash_table_find(cache->name_table, name, NULL, (void *)ret))
506 /* Allocates ID cache list. */
508 static SilcIDCacheList silc_idcache_list_alloc()
510 SilcIDCacheList list;
512 list = silc_calloc(1, sizeof(*list));
519 /* Adds cache entry to the ID cache list. If needed reallocates memory
522 static void silc_idcache_list_add(SilcIDCacheList list, SilcIDCacheEntry cache)
526 /* Try to add to static cache */
527 if (!list->cache_dyn_count)
528 for (i = 0; i < (sizeof(list->cache) / sizeof(list->cache[0])); i++) {
529 if (!list->cache[i]) {
530 list->cache[i] = cache;
536 /* Static cache is full, allocate dynamic cache */
537 for (i = 0; i < list->cache_dyn_count; i++) {
538 if (!list->cache_dyn[i]) {
539 list->cache_dyn[i] = cache;
545 if (i >= list->cache_dyn_count) {
548 i = list->cache_dyn_count;
549 list->cache_dyn = silc_realloc(list->cache_dyn,
550 sizeof(*list->cache_dyn) * (i + 5));
551 if (!list->cache_dyn)
554 /* NULL the reallocated area */
555 for (k = i; k < (i + 5); k++)
556 list->cache_dyn[k] = NULL;
558 list->cache_dyn[i] = cache;
560 list->cache_dyn_count += 5;
564 /* Returns number of cache entries in the ID cache list. */
566 int silc_idcache_list_count(SilcIDCacheList list)
568 return list->cache_count;
571 /* Returns first entry from the ID cache list. */
573 bool silc_idcache_list_first(SilcIDCacheList list, SilcIDCacheEntry *ret)
577 if (!list->cache[list->pos])
581 *ret = list->cache[list->pos];
586 /* Returns next entry from the ID cache list. */
588 bool silc_idcache_list_next(SilcIDCacheList list, SilcIDCacheEntry *ret)
593 list->pos >= (sizeof(list->cache) / sizeof(list->cache[0]))) {
598 if (list->dyn && list->pos >= list->cache_dyn_count)
601 if (!list->dyn && !list->cache[list->pos])
604 if (list->dyn && !list->cache_dyn[list->pos])
609 *ret = list->cache[list->pos];
611 *ret = list->cache_dyn[list->pos];
617 /* Frees ID cache list. User must free the list object returned by
618 any of the searching functions. */
620 void silc_idcache_list_free(SilcIDCacheList list)
624 silc_free(list->cache_dyn);