1 /* GLIB - Library of useful routines for C programming
2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
17 * Boston, MA 02111-1307, USA.
21 * Modified by the GLib Team and others 1997-2000. See the AUTHORS
22 * file for a list of people on the GLib Team. See the ChangeLog
23 * files for a list of changes. These files are distributed with
24 * GLib at ftp://ftp.gtk.org/pub/gtk/.
36 #define HASH_TABLE_MIN_SIZE 11
37 #define HASH_TABLE_MAX_SIZE 13845163
40 typedef struct _GHashNode GHashNode;
55 GEqualFunc key_equal_func;
56 GDestroyNotify key_destroy_func;
57 GDestroyNotify value_destroy_func;
60 #define G_HASH_TABLE_RESIZE(hash_table) \
62 if ((hash_table->size >= 3 * hash_table->nnodes && \
63 hash_table->size > HASH_TABLE_MIN_SIZE) || \
64 (3 * hash_table->size <= hash_table->nnodes && \
65 hash_table->size < HASH_TABLE_MAX_SIZE)) \
66 g_hash_table_resize (hash_table); \
69 static void g_hash_table_resize (GHashTable *hash_table);
70 static GHashNode** g_hash_table_lookup_node (GHashTable *hash_table,
72 static GHashNode* g_hash_node_new (gpointer key,
74 static void g_hash_node_destroy (GHashNode *hash_node,
75 GDestroyNotify key_destroy_func,
76 GDestroyNotify value_destroy_func);
77 static void g_hash_nodes_destroy (GHashNode *hash_node,
78 GDestroyNotify key_destroy_func,
79 GDestroyNotify value_destroy_func);
80 static guint g_hash_table_foreach_remove_or_steal (GHashTable *hash_table,
86 #ifndef DISABLE_MEM_POOLS
87 G_LOCK_DEFINE_STATIC (g_hash_global);
89 static GMemChunk *node_mem_chunk = NULL;
90 static GHashNode *node_free_list = NULL;
95 * @hash_func: a function to create a hash value from a key.
96 * Hash values are used to determine where keys are stored within the
97 * #GHashTable data structure. The g_direct_hash(), g_int_hash() and
98 * g_str_hash() functions are provided for some common types of keys.
99 * If hash_func is %NULL, g_direct_hash() is used.
100 * @key_equal_func: a function to check two keys for equality. This is
101 * used when looking up keys in the #GHashTable. The g_direct_equal(),
102 * g_int_equal() and g_str_equal() functions are provided for the most
103 * common types of keys. If @key_equal_func is %NULL, keys are compared
104 * directly in a similar fashion to g_direct_equal(), but without the
105 * overhead of a function call.
107 * Creates a new #GHashTable.
109 * Return value: a new #GHashTable.
112 g_hash_table_new (GHashFunc hash_func,
113 GEqualFunc key_equal_func)
115 return g_hash_table_new_full (hash_func, key_equal_func, NULL, NULL);
120 * g_hash_table_new_full:
121 * @hash_func: a function to create a hash value from a key.
122 * @key_equal_func: a function to check two keys for equality.
123 * @key_destroy_func: a function to free the memory allocated for the key
124 * used when removing the entry from the #GHashTable or %NULL if you
125 * don't want to supply such a function.
126 * @value_destroy_func: a function to free the memory allocated for the
127 * value used when removing the entry from the #GHashTable or %NULL if
128 * you don't want to supply such a function.
130 * Creates a new #GHashTable like g_hash_table_new() and allows to specify
131 * functions to free the memory allocated for the key and value that get
132 * called when removing the entry from the #GHashTable.
134 * Return value: a new #GHashTable.
137 g_hash_table_new_full (GHashFunc hash_func,
138 GEqualFunc key_equal_func,
139 GDestroyNotify key_destroy_func,
140 GDestroyNotify value_destroy_func)
142 GHashTable *hash_table;
145 hash_table = g_new (GHashTable, 1);
146 hash_table->size = HASH_TABLE_MIN_SIZE;
147 hash_table->nnodes = 0;
148 hash_table->hash_func = hash_func ? hash_func : g_direct_hash;
149 hash_table->key_equal_func = key_equal_func;
150 hash_table->key_destroy_func = key_destroy_func;
151 hash_table->value_destroy_func = value_destroy_func;
152 hash_table->nodes = g_new (GHashNode*, hash_table->size);
154 for (i = 0; i < hash_table->size; i++)
155 hash_table->nodes[i] = NULL;
161 * g_hash_table_destroy:
162 * @hash_table: a #GHashTable.
164 * Destroys the #GHashTable. If keys and/or values are dynamically
165 * allocated, you should either free them first or create the #GHashTable
166 * using g_hash_table_new_full(). In the latter case the destroy functions
167 * you supplied will be called on all keys and values before destroying
171 g_hash_table_destroy (GHashTable *hash_table)
175 g_return_if_fail (hash_table != NULL);
177 for (i = 0; i < hash_table->size; i++)
178 g_hash_nodes_destroy (hash_table->nodes[i],
179 hash_table->key_destroy_func,
180 hash_table->value_destroy_func);
182 g_free (hash_table->nodes);
186 static inline GHashNode**
187 g_hash_table_lookup_node (GHashTable *hash_table,
192 node = &hash_table->nodes
193 [(* hash_table->hash_func) (key) % hash_table->size];
195 /* Hash table lookup needs to be fast.
196 * We therefore remove the extra conditional of testing
197 * whether to call the key_equal_func or not from
200 if (hash_table->key_equal_func)
201 while (*node && !(*hash_table->key_equal_func) ((*node)->key, key))
202 node = &(*node)->next;
204 while (*node && (*node)->key != key)
205 node = &(*node)->next;
211 * g_hash_table_lookup:
212 * @hash_table: a #GHashTable.
213 * @key: the key to look up.
215 * Looks up a key in a #GHashTable. Note that this function cannot
216 * distinguish between a key that is not present and one which is present
217 * and has the value %NULL. If you need this distinction, use
218 * g_hash_table_lookup_extended().
220 * Return value: the associated value, or %NULL if the key is not found.
223 g_hash_table_lookup (GHashTable *hash_table,
228 g_return_val_if_fail (hash_table != NULL, NULL);
230 node = *g_hash_table_lookup_node (hash_table, key);
232 return node ? node->value : NULL;
236 * g_hash_table_lookup_extended:
237 * @hash_table: a #GHashTable.
238 * @lookup_key: the key to look up.
239 * @orig_key: returns the original key.
240 * @value: returns the value associated with the key.
242 * Looks up a key in the #GHashTable, returning the original key and the
243 * associated value and a #gboolean which is %TRUE if the key was found. This
244 * is useful if you need to free the memory allocated for the original key,
245 * for example before calling g_hash_table_remove().
247 * Return value: %TRUE if the key was found in the #GHashTable.
250 g_hash_table_lookup_extended (GHashTable *hash_table,
251 gconstpointer lookup_key,
257 g_return_val_if_fail (hash_table != NULL, FALSE);
259 node = *g_hash_table_lookup_node (hash_table, lookup_key);
264 *orig_key = node->key;
266 *value = node->value;
274 * g_hash_table_insert:
275 * @hash_table: a #GHashTable.
276 * @key: a key to insert.
277 * @value: the value to associate with the key.
279 * Inserts a new key and value into a #GHashTable.
281 * If the key already exists in the #GHashTable its current value is replaced
282 * with the new value. If you supplied a @value_destroy_func when creating the
283 * #GHashTable, the old value is freed using that function. If you supplied
284 * a @key_destroy_func when creating the #GHashTable, the passed key is freed
285 * using that function.
288 g_hash_table_insert (GHashTable *hash_table,
294 g_return_if_fail (hash_table != NULL);
296 node = g_hash_table_lookup_node (hash_table, key);
300 /* do not reset node->key in this place, keeping
301 * the old key is the intended behaviour.
302 * g_hash_table_replace() can be used instead.
305 /* free the passed key */
306 if (hash_table->key_destroy_func)
307 hash_table->key_destroy_func (key);
309 if (hash_table->value_destroy_func)
310 hash_table->value_destroy_func ((*node)->value);
312 (*node)->value = value;
316 *node = g_hash_node_new (key, value);
317 hash_table->nnodes++;
318 G_HASH_TABLE_RESIZE (hash_table);
323 * g_hash_table_replace:
324 * @hash_table: a #GHashTable.
325 * @key: a key to insert.
326 * @value: the value to associate with the key.
328 * Inserts a new key and value into a #GHashTable similar to
329 * g_hash_table_insert(). The difference is that if the key already exists
330 * in the #GHashTable, it gets replaced by the new key. If you supplied a
331 * @value_destroy_func when creating the #GHashTable, the old value is freed
332 * using that function. If you supplied a @key_destroy_func when creating the
333 * #GHashTable, the old key is freed using that function.
336 g_hash_table_replace (GHashTable *hash_table,
342 g_return_if_fail (hash_table != NULL);
344 node = g_hash_table_lookup_node (hash_table, key);
348 if (hash_table->key_destroy_func)
349 hash_table->key_destroy_func ((*node)->key);
351 if (hash_table->value_destroy_func)
352 hash_table->value_destroy_func ((*node)->value);
355 (*node)->value = value;
359 *node = g_hash_node_new (key, value);
360 hash_table->nnodes++;
361 G_HASH_TABLE_RESIZE (hash_table);
366 * g_hash_table_remove:
367 * @hash_table: a #GHashTable.
368 * @key: the key to remove.
370 * Removes a key and its associated value from a #GHashTable.
372 * If the #GHashTable was created using g_hash_table_new_full(), the
373 * key and value are freed using the supplied destroy functions, otherwise
374 * you have to make sure that any dynamically allocated values are freed
377 * Return value: %TRUE if the key was found and removed from the #GHashTable.
380 g_hash_table_remove (GHashTable *hash_table,
383 GHashNode **node, *dest;
385 g_return_val_if_fail (hash_table != NULL, FALSE);
387 node = g_hash_table_lookup_node (hash_table, key);
391 (*node) = dest->next;
392 g_hash_node_destroy (dest,
393 hash_table->key_destroy_func,
394 hash_table->value_destroy_func);
395 hash_table->nnodes--;
397 G_HASH_TABLE_RESIZE (hash_table);
406 * g_hash_table_steal:
407 * @hash_table: a #GHashTable.
408 * @key: the key to remove.
410 * Removes a key and its associated value from a #GHashTable without
411 * calling the key and value destroy functions.
413 * Return value: %TRUE if the key was found and removed from the #GHashTable.
416 g_hash_table_steal (GHashTable *hash_table,
419 GHashNode **node, *dest;
421 g_return_val_if_fail (hash_table != NULL, FALSE);
423 node = g_hash_table_lookup_node (hash_table, key);
427 (*node) = dest->next;
428 g_hash_node_destroy (dest, NULL, NULL);
429 hash_table->nnodes--;
431 G_HASH_TABLE_RESIZE (hash_table);
440 * g_hash_table_foreach_remove:
441 * @hash_table: a #GHashTable.
442 * @func: the function to call for each key/value pair.
443 * @user_data: user data to pass to the function.
445 * Calls the given function for each key/value pair in the #GHashTable.
446 * If the function returns %TRUE, then the key/value pair is removed from the
447 * #GHashTable. If you supplied key or value destroy functions when creating
448 * the #GHashTable, they are used to free the memory allocated for the removed
451 * Return value: the number of key/value pairs removed.
454 g_hash_table_foreach_remove (GHashTable *hash_table,
458 g_return_val_if_fail (hash_table != NULL, 0);
459 g_return_val_if_fail (func != NULL, 0);
461 return g_hash_table_foreach_remove_or_steal (hash_table, func, user_data, TRUE);
465 * g_hash_table_foreach_steal:
466 * @hash_table: a #GHashTable.
467 * @func: the function to call for each key/value pair.
468 * @user_data: user data to pass to the function.
470 * Calls the given function for each key/value pair in the #GHashTable.
471 * If the function returns %TRUE, then the key/value pair is removed from the
472 * #GHashTable, but no key or value destroy functions are called.
474 * Return value: the number of key/value pairs removed.
477 g_hash_table_foreach_steal (GHashTable *hash_table,
481 g_return_val_if_fail (hash_table != NULL, 0);
482 g_return_val_if_fail (func != NULL, 0);
484 return g_hash_table_foreach_remove_or_steal (hash_table, func, user_data, FALSE);
488 g_hash_table_foreach_remove_or_steal (GHashTable *hash_table,
493 GHashNode *node, *prev;
497 for (i = 0; i < hash_table->size; i++)
503 for (node = hash_table->nodes[i]; node; prev = node, node = node->next)
505 if ((* func) (node->key, node->value, user_data))
509 hash_table->nnodes -= 1;
513 prev->next = node->next;
514 g_hash_node_destroy (node,
515 notify ? hash_table->key_destroy_func : NULL,
516 notify ? hash_table->value_destroy_func : NULL);
521 hash_table->nodes[i] = node->next;
522 g_hash_node_destroy (node,
523 notify ? hash_table->key_destroy_func : NULL,
524 notify ? hash_table->value_destroy_func : NULL);
531 G_HASH_TABLE_RESIZE (hash_table);
537 * g_hash_table_foreach:
538 * @hash_table: a #GHashTable.
539 * @func: the function to call for each key/value pair.
540 * @user_data: user data to pass to the function.
542 * Calls the given function for each of the key/value pairs in the
543 * #GHashTable. The function is passed the key and value of each
544 * pair, and the given @user_data parameter. The hash table may not
545 * be modified while iterating over it (you can't add/remove
546 * items). To remove all items matching a predicate, use
547 * g_hash_table_remove().
550 g_hash_table_foreach (GHashTable *hash_table,
557 g_return_if_fail (hash_table != NULL);
558 g_return_if_fail (func != NULL);
560 for (i = 0; i < hash_table->size; i++)
561 for (node = hash_table->nodes[i]; node; node = node->next)
562 (* func) (node->key, node->value, user_data);
567 * @hash_table: a #GHashTable.
568 * @predicate: function to test the key/value pairs for a certain property.
569 * @user_data: user data to pass to the function.
571 * Calls the given function for key/value pairs in the #GHashTable until
572 * @predicate returns %TRUE. The function is passed the key and value of
573 * each pair, and the given @user_data parameter. The hash table may not
574 * be modified while iterating over it (you can't add/remove items).
576 * Return value: The value of the first key/value pair is returned, for which
577 * func evaluates to %TRUE. If no pair with the requested property is found,
583 g_hash_table_find (GHashTable *hash_table,
590 g_return_val_if_fail (hash_table != NULL, NULL);
591 g_return_val_if_fail (predicate != NULL, NULL);
593 for (i = 0; i < hash_table->size; i++)
594 for (node = hash_table->nodes[i]; node; node = node->next)
595 if (predicate (node->key, node->value, user_data))
602 * @hash_table: a #GHashTable.
604 * Returns the number of elements contained in the #GHashTable.
606 * Return value: the number of key/value pairs in the #GHashTable.
609 g_hash_table_size (GHashTable *hash_table)
611 g_return_val_if_fail (hash_table != NULL, 0);
613 return hash_table->nnodes;
617 g_hash_table_resize (GHashTable *hash_table)
619 GHashNode **new_nodes;
626 new_size = g_spaced_primes_closest (hash_table->nnodes);
627 new_size = CLAMP (new_size, HASH_TABLE_MIN_SIZE, HASH_TABLE_MAX_SIZE);
629 new_nodes = g_new0 (GHashNode*, new_size);
631 for (i = 0; i < hash_table->size; i++)
632 for (node = hash_table->nodes[i]; node; node = next)
636 hash_val = (* hash_table->hash_func) (node->key) % new_size;
638 node->next = new_nodes[hash_val];
639 new_nodes[hash_val] = node;
642 g_free (hash_table->nodes);
643 hash_table->nodes = new_nodes;
644 hash_table->size = new_size;
648 g_hash_node_new (gpointer key,
651 GHashNode *hash_node;
653 #ifdef DISABLE_MEM_POOLS
654 hash_node = g_new (GHashNode, 1);
656 G_LOCK (g_hash_global);
659 hash_node = node_free_list;
660 node_free_list = node_free_list->next;
665 node_mem_chunk = g_mem_chunk_new ("hash node mem chunk",
669 hash_node = g_chunk_new (GHashNode, node_mem_chunk);
671 G_UNLOCK (g_hash_global);
674 hash_node->key = key;
675 hash_node->value = value;
676 hash_node->next = NULL;
682 g_hash_node_destroy (GHashNode *hash_node,
683 GDestroyNotify key_destroy_func,
684 GDestroyNotify value_destroy_func)
686 if (key_destroy_func)
687 key_destroy_func (hash_node->key);
688 if (value_destroy_func)
689 value_destroy_func (hash_node->value);
691 #ifdef ENABLE_GC_FRIENDLY
692 hash_node->key = NULL;
693 hash_node->value = NULL;
694 #endif /* ENABLE_GC_FRIENDLY */
696 #ifdef DISABLE_MEM_POOLS
699 G_LOCK (g_hash_global);
700 hash_node->next = node_free_list;
701 node_free_list = hash_node;
702 G_UNLOCK (g_hash_global);
707 g_hash_nodes_destroy (GHashNode *hash_node,
708 GFreeFunc key_destroy_func,
709 GFreeFunc value_destroy_func)
711 #ifdef DISABLE_MEM_POOLS
714 GHashNode *next = hash_node->next;
716 if (key_destroy_func)
717 key_destroy_func (hash_node->key);
718 if (value_destroy_func)
719 value_destroy_func (hash_node->value);
727 GHashNode *node = hash_node;
731 if (key_destroy_func)
732 key_destroy_func (node->key);
733 if (value_destroy_func)
734 value_destroy_func (node->value);
736 #ifdef ENABLE_GC_FRIENDLY
739 #endif /* ENABLE_GC_FRIENDLY */
744 if (key_destroy_func)
745 key_destroy_func (node->key);
746 if (value_destroy_func)
747 value_destroy_func (node->value);
749 #ifdef ENABLE_GC_FRIENDLY
752 #endif /* ENABLE_GC_FRIENDLY */
754 G_LOCK (g_hash_global);
755 node->next = node_free_list;
756 node_free_list = hash_node;
757 G_UNLOCK (g_hash_global);