2 This file is part of GNUnet.
3 (C) 2008 Christian Grothoff (and other contributing authors)
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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
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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.
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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"
32 * An entry in the hash map.
48 * If there is a hash collision, we create a linked list.
50 struct MapEntry *next;
55 * Internal representation of the hash map.
57 struct GNUNET_CONTAINER_MultiHashMap
63 struct MapEntry **map;
66 * Number of entries in the map.
71 * Length of the "map" array.
73 unsigned int map_length;
78 * Create a multi hash map.
80 * @param len initial size (map will grow as needed)
81 * @return NULL on error
83 struct GNUNET_CONTAINER_MultiHashMap *
84 GNUNET_CONTAINER_multihashmap_create (unsigned int len)
86 struct GNUNET_CONTAINER_MultiHashMap *ret;
88 GNUNET_assert (len > 0);
89 ret = GNUNET_malloc (sizeof (struct GNUNET_CONTAINER_MultiHashMap));
90 ret->map = GNUNET_malloc (len * sizeof (struct MapEntry *));
91 ret->map_length = len;
97 * Destroy a hash map. Will not free any values
98 * stored in the hash map!
103 GNUNET_CONTAINER_multihashmap_destroy (struct GNUNET_CONTAINER_MultiHashMap
109 for (i = 0; i < map->map_length; i++)
111 while (NULL != (e = map->map[i]))
113 map->map[i] = e->next;
117 GNUNET_free (map->map);
123 * Compute the index of the bucket for the given key.
125 * @param m hash map for which to compute the index
126 * @param key what key should the index be computed for
127 * @return offset into the "map" array of "m"
130 idx_of (const struct GNUNET_CONTAINER_MultiHashMap *m,
131 const GNUNET_HashCode * key)
133 GNUNET_assert (m != NULL);
134 return (*(unsigned int *) key) % m->map_length;
139 * Get the number of key-value pairs in the map.
142 * @return the number of key value pairs
145 GNUNET_CONTAINER_multihashmap_size (const struct GNUNET_CONTAINER_MultiHashMap
153 * Given a key find a value in the map matching the key.
156 * @param key what to look for
157 * @return NULL if no value was found; note that
158 * this is indistinguishable from values that just
159 * happen to be NULL; use "contains" to test for
160 * key-value pairs with value NULL
163 GNUNET_CONTAINER_multihashmap_get (const struct GNUNET_CONTAINER_MultiHashMap
164 *map, const GNUNET_HashCode * key)
168 e = map->map[idx_of (map, key)];
171 if (0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
180 * Iterate over all entries in the map.
183 * @param it function to call on each entry
184 * @param it_cls extra argument to it
185 * @return the number of key value pairs processed,
186 * GNUNET_SYSERR if it aborted iteration
189 GNUNET_CONTAINER_multihashmap_iterate (const struct
190 GNUNET_CONTAINER_MultiHashMap *map,
191 GNUNET_CONTAINER_HashMapIterator it,
201 GNUNET_assert (map != NULL);
202 for (i = 0; i < map->map_length; i++)
205 while (NULL != (e = n))
211 if (GNUNET_OK != it (it_cls, &kc, e->value))
212 return GNUNET_SYSERR;
222 * Remove the given key-value pair from the map. Note that if the
223 * key-value pair is in the map multiple times, only one of the pairs
227 * @param key key of the key-value pair
228 * @param value value of the key-value pair
229 * @return GNUNET_YES on success, GNUNET_NO if the key-value pair
233 GNUNET_CONTAINER_multihashmap_remove (struct GNUNET_CONTAINER_MultiHashMap *map,
234 const GNUNET_HashCode * key, void *value)
240 i = idx_of (map, key);
245 if ((0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode))) &&
249 map->map[i] = e->next;
264 * Remove all entries for the given key from the map.
265 * Note that the values would not be "freed".
268 * @param key identifies values to be removed
269 * @return number of values removed
272 GNUNET_CONTAINER_multihashmap_remove_all (struct GNUNET_CONTAINER_MultiHashMap
273 *map, const GNUNET_HashCode * key)
281 i = idx_of (map, key);
286 if (0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
289 map->map[i] = e->next;
311 * Check if the map contains any value under the given
312 * key (including values that are NULL).
315 * @param key the key to test if a value exists for it
316 * @return GNUNET_YES if such a value exists,
320 GNUNET_CONTAINER_multihashmap_contains (const struct
321 GNUNET_CONTAINER_MultiHashMap *map,
322 const GNUNET_HashCode * key)
326 e = map->map[idx_of (map, key)];
329 if (0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
338 * Check if the map contains the given value under the given
342 * @param key the key to test if a value exists for it
343 * @param value value to test for
344 * @return GNUNET_YES if such a value exists,
348 GNUNET_CONTAINER_multihashmap_contains_value (const struct
349 GNUNET_CONTAINER_MultiHashMap
350 *map, const GNUNET_HashCode * key,
355 e = map->map[idx_of (map, key)];
358 if ((0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode))) &&
368 * Grow the given map to a more appropriate size.
370 * @param map the hash map to grow
373 grow (struct GNUNET_CONTAINER_MultiHashMap *map)
375 struct MapEntry **old_map;
376 struct MapEntry **new_map;
378 unsigned int old_len;
379 unsigned int new_len;
384 old_len = map->map_length;
385 new_len = old_len * 2;
386 new_map = GNUNET_malloc (sizeof (struct MapEntry *) * new_len);
387 map->map_length = new_len;
389 for (i = 0; i < old_len; i++)
391 while (NULL != (e = old_map[i]))
393 old_map[i] = e->next;
394 idx = idx_of (map, &e->key);
395 e->next = new_map[idx];
399 GNUNET_free (old_map);
404 * Store a key-value pair in the map.
407 * @param key key to use
408 * @param value value to use
409 * @param opt options for put
410 * @return GNUNET_OK on success,
411 * GNUNET_NO if a value was replaced (with REPLACE)
412 * GNUNET_SYSERR if UNIQUE_ONLY was the option and the
413 * value already exists
416 GNUNET_CONTAINER_multihashmap_put (struct GNUNET_CONTAINER_MultiHashMap *map,
417 const GNUNET_HashCode * key, void *value,
418 enum GNUNET_CONTAINER_MultiHashMapOption opt)
423 i = idx_of (map, key);
424 if ((opt != GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE) &&
425 (opt != GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
430 if (0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
432 if (opt == GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY)
433 return GNUNET_SYSERR;
440 if (map->size / 3 >= map->map_length / 4)
443 i = idx_of (map, key);
445 e = GNUNET_malloc (sizeof (struct MapEntry));
448 e->next = map->map[i];
456 * Iterate over all entries in the map that match a particular key.
459 * @param key key that the entries must correspond to
460 * @param it function to call on each entry
461 * @param it_cls extra argument to it
462 * @return the number of key value pairs processed,
463 * GNUNET_SYSERR if it aborted iteration
466 GNUNET_CONTAINER_multihashmap_get_multiple (const struct
467 GNUNET_CONTAINER_MultiHashMap *map,
468 const GNUNET_HashCode * key,
469 GNUNET_CONTAINER_HashMapIterator it,
477 n = map->map[idx_of (map, key)];
478 while (NULL != (e = n))
481 if (0 != memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
483 if ((it != NULL) && (GNUNET_OK != it (it_cls, key, e->value)))
484 return GNUNET_SYSERR;
491 /* end of container_multihashmap.c */