2 This file is part of GNUnet.
3 (C) 2008 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 2, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
21 * @file util/container_multihashmap.c
22 * @brief hash map where the same key may be present multiple times
23 * @author Christian Grothoff
27 #include "gnunet_common.h"
28 #include "gnunet_container_lib.h"
29 #include "gnunet_crypto_lib.h"
31 #define LOG(kind,...) GNUNET_log_from (kind, "util", __VA_ARGS__)
34 * An entry in the hash map.
50 * If there is a hash collision, we create a linked list.
52 struct MapEntry *next;
57 * Internal representation of the hash map.
59 struct GNUNET_CONTAINER_MultiHashMap
65 struct MapEntry **map;
68 * Number of entries in the map.
73 * Length of the "map" array.
75 unsigned int map_length;
80 * Create a multi hash map.
82 * @param len initial size (map will grow as needed)
83 * @return NULL on error
85 struct GNUNET_CONTAINER_MultiHashMap *
86 GNUNET_CONTAINER_multihashmap_create (unsigned int len)
88 struct GNUNET_CONTAINER_MultiHashMap *ret;
90 GNUNET_assert (len > 0);
91 ret = GNUNET_malloc (sizeof (struct GNUNET_CONTAINER_MultiHashMap));
92 ret->map = GNUNET_malloc (len * sizeof (struct MapEntry *));
93 ret->map_length = len;
99 * Destroy a hash map. Will not free any values
100 * stored in the hash map!
105 GNUNET_CONTAINER_multihashmap_destroy (struct GNUNET_CONTAINER_MultiHashMap
111 for (i = 0; i < map->map_length; i++)
113 while (NULL != (e = map->map[i]))
115 map->map[i] = e->next;
119 GNUNET_free (map->map);
125 * Compute the index of the bucket for the given key.
127 * @param m hash map for which to compute the index
128 * @param key what key should the index be computed for
129 * @return offset into the "map" array of "m"
132 idx_of (const struct GNUNET_CONTAINER_MultiHashMap *m,
133 const GNUNET_HashCode * key)
135 GNUNET_assert (m != NULL);
136 return (*(unsigned int *) key) % m->map_length;
141 * Get the number of key-value pairs in the map.
144 * @return the number of key value pairs
147 GNUNET_CONTAINER_multihashmap_size (const struct GNUNET_CONTAINER_MultiHashMap
155 * Given a key find a value in the map matching the key.
158 * @param key what to look for
159 * @return NULL if no value was found; note that
160 * this is indistinguishable from values that just
161 * happen to be NULL; use "contains" to test for
162 * key-value pairs with value NULL
165 GNUNET_CONTAINER_multihashmap_get (const struct GNUNET_CONTAINER_MultiHashMap
166 *map, const GNUNET_HashCode * key)
170 e = map->map[idx_of (map, key)];
173 if (0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
182 * Iterate over all entries in the map.
185 * @param it function to call on each entry
186 * @param it_cls extra argument to it
187 * @return the number of key value pairs processed,
188 * GNUNET_SYSERR if it aborted iteration
191 GNUNET_CONTAINER_multihashmap_iterate (const struct
192 GNUNET_CONTAINER_MultiHashMap *map,
193 GNUNET_CONTAINER_HashMapIterator it,
203 GNUNET_assert (map != NULL);
204 for (i = 0; i < map->map_length; i++)
207 while (NULL != (e = n))
213 if (GNUNET_OK != it (it_cls, &kc, e->value))
214 return GNUNET_SYSERR;
224 * Remove the given key-value pair from the map. Note that if the
225 * key-value pair is in the map multiple times, only one of the pairs
229 * @param key key of the key-value pair
230 * @param value value of the key-value pair
231 * @return GNUNET_YES on success, GNUNET_NO if the key-value pair
235 GNUNET_CONTAINER_multihashmap_remove (struct GNUNET_CONTAINER_MultiHashMap
236 *map, const GNUNET_HashCode * key,
243 i = idx_of (map, key);
248 if ((0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode))) &&
252 map->map[i] = e->next;
267 * Remove all entries for the given key from the map.
268 * Note that the values would not be "freed".
271 * @param key identifies values to be removed
272 * @return number of values removed
275 GNUNET_CONTAINER_multihashmap_remove_all (struct GNUNET_CONTAINER_MultiHashMap
276 *map, const GNUNET_HashCode * key)
284 i = idx_of (map, key);
289 if (0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
292 map->map[i] = e->next;
314 * Check if the map contains any value under the given
315 * key (including values that are NULL).
318 * @param key the key to test if a value exists for it
319 * @return GNUNET_YES if such a value exists,
323 GNUNET_CONTAINER_multihashmap_contains (const struct
324 GNUNET_CONTAINER_MultiHashMap *map,
325 const GNUNET_HashCode * key)
329 e = map->map[idx_of (map, key)];
332 if (0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
341 * Check if the map contains the given value under the given
345 * @param key the key to test if a value exists for it
346 * @param value value to test for
347 * @return GNUNET_YES if such a value exists,
351 GNUNET_CONTAINER_multihashmap_contains_value (const struct
352 GNUNET_CONTAINER_MultiHashMap
354 const GNUNET_HashCode * key,
359 e = map->map[idx_of (map, key)];
362 if ((0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode))) &&
372 * Grow the given map to a more appropriate size.
374 * @param map the hash map to grow
377 grow (struct GNUNET_CONTAINER_MultiHashMap *map)
379 struct MapEntry **old_map;
380 struct MapEntry **new_map;
382 unsigned int old_len;
383 unsigned int new_len;
388 old_len = map->map_length;
389 new_len = old_len * 2;
390 new_map = GNUNET_malloc (sizeof (struct MapEntry *) * new_len);
391 map->map_length = new_len;
393 for (i = 0; i < old_len; i++)
395 while (NULL != (e = old_map[i]))
397 old_map[i] = e->next;
398 idx = idx_of (map, &e->key);
399 e->next = new_map[idx];
403 GNUNET_free (old_map);
408 * Store a key-value pair in the map.
411 * @param key key to use
412 * @param value value to use
413 * @param opt options for put
414 * @return GNUNET_OK on success,
415 * GNUNET_NO if a value was replaced (with REPLACE)
416 * GNUNET_SYSERR if UNIQUE_ONLY was the option and the
417 * value already exists
420 GNUNET_CONTAINER_multihashmap_put (struct GNUNET_CONTAINER_MultiHashMap *map,
421 const GNUNET_HashCode * key, void *value,
422 enum GNUNET_CONTAINER_MultiHashMapOption
428 i = idx_of (map, key);
429 if ((opt != GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE) &&
430 (opt != GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
435 if (0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
437 if (opt == GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY)
438 return GNUNET_SYSERR;
445 if (map->size / 3 >= map->map_length / 4)
448 i = idx_of (map, key);
450 e = GNUNET_malloc (sizeof (struct MapEntry));
453 e->next = map->map[i];
461 * Iterate over all entries in the map that match a particular key.
464 * @param key key that the entries must correspond to
465 * @param it function to call on each entry
466 * @param it_cls extra argument to it
467 * @return the number of key value pairs processed,
468 * GNUNET_SYSERR if it aborted iteration
471 GNUNET_CONTAINER_multihashmap_get_multiple (const struct
472 GNUNET_CONTAINER_MultiHashMap
473 *map, const GNUNET_HashCode * key,
474 GNUNET_CONTAINER_HashMapIterator
482 n = map->map[idx_of (map, key)];
483 while (NULL != (e = n))
486 if (0 != memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
488 if ((it != NULL) && (GNUNET_OK != it (it_cls, key, e->value)))
489 return GNUNET_SYSERR;
496 /* end of container_multihashmap.c */