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/.
37 #define HASH_TABLE_MIN_SIZE 11
38 #define HASH_TABLE_MAX_SIZE 13845163
41 typedef struct _GHashNode GHashNode;
56 GEqualFunc key_equal_func;
57 volatile gint ref_count;
58 GDestroyNotify key_destroy_func;
59 GDestroyNotify value_destroy_func;
62 #define G_HASH_TABLE_RESIZE(hash_table) \
64 if ((hash_table->size >= 3 * hash_table->nnodes && \
65 hash_table->size > HASH_TABLE_MIN_SIZE) || \
66 (3 * hash_table->size <= hash_table->nnodes && \
67 hash_table->size < HASH_TABLE_MAX_SIZE)) \
68 g_hash_table_resize (hash_table); \
71 static void g_hash_table_resize (GHashTable *hash_table);
72 static GHashNode** g_hash_table_lookup_node (GHashTable *hash_table,
74 static GHashNode* g_hash_node_new (gpointer key,
76 static void g_hash_node_destroy (GHashNode *hash_node,
77 GDestroyNotify key_destroy_func,
78 GDestroyNotify value_destroy_func);
79 static void g_hash_nodes_destroy (GHashNode *hash_node,
80 GDestroyNotify key_destroy_func,
81 GDestroyNotify value_destroy_func);
82 static guint g_hash_table_foreach_remove_or_steal (GHashTable *hash_table,
90 * @hash_func: a function to create a hash value from a key.
91 * Hash values are used to determine where keys are stored within the
92 * #GHashTable data structure. The g_direct_hash(), g_int_hash() and
93 * g_str_hash() functions are provided for some common types of keys.
94 * If hash_func is %NULL, g_direct_hash() is used.
95 * @key_equal_func: a function to check two keys for equality. This is
96 * used when looking up keys in the #GHashTable. The g_direct_equal(),
97 * g_int_equal() and g_str_equal() functions are provided for the most
98 * common types of keys. If @key_equal_func is %NULL, keys are compared
99 * directly in a similar fashion to g_direct_equal(), but without the
100 * overhead of a function call.
102 * Creates a new #GHashTable with a reference count of 1.
104 * Return value: a new #GHashTable.
107 g_hash_table_new (GHashFunc hash_func,
108 GEqualFunc key_equal_func)
110 return g_hash_table_new_full (hash_func, key_equal_func, NULL, NULL);
115 * g_hash_table_new_full:
116 * @hash_func: a function to create a hash value from a key.
117 * @key_equal_func: a function to check two keys for equality.
118 * @key_destroy_func: a function to free the memory allocated for the key
119 * used when removing the entry from the #GHashTable or %NULL if you
120 * don't want to supply such a function.
121 * @value_destroy_func: a function to free the memory allocated for the
122 * value used when removing the entry from the #GHashTable or %NULL if
123 * you don't want to supply such a function.
125 * Creates a new #GHashTable like g_hash_table_new() with a reference count
126 * of 1 and allows to specify functions to free the memory allocated for the
127 * key and value that get called when removing the entry from the #GHashTable.
129 * Return value: a new #GHashTable.
132 g_hash_table_new_full (GHashFunc hash_func,
133 GEqualFunc key_equal_func,
134 GDestroyNotify key_destroy_func,
135 GDestroyNotify value_destroy_func)
137 GHashTable *hash_table;
139 hash_table = g_slice_new (GHashTable);
140 hash_table->size = HASH_TABLE_MIN_SIZE;
141 hash_table->nnodes = 0;
142 hash_table->hash_func = hash_func ? hash_func : g_direct_hash;
143 hash_table->key_equal_func = key_equal_func;
144 hash_table->ref_count = 1;
145 hash_table->key_destroy_func = key_destroy_func;
146 hash_table->value_destroy_func = value_destroy_func;
147 hash_table->nodes = g_new0 (GHashNode*, hash_table->size);
155 * @hash_table: a valid #GHashTable.
157 * Atomically increments the reference count of @hash_table by one.
158 * This function is MT-safe and may be called from any thread.
160 * Return value: the passed in #GHashTable.
165 g_hash_table_ref (GHashTable *hash_table)
167 g_return_val_if_fail (hash_table != NULL, NULL);
168 g_return_val_if_fail (hash_table->ref_count > 0, hash_table);
170 g_atomic_int_add (&hash_table->ref_count, 1);
175 * g_hash_table_unref:
176 * @hash_table: a valid #GHashTable.
178 * Atomically decrements the reference count of @hash_table by one.
179 * If the reference count drops to 0, all keys and values will be
180 * destroyed, and all memory allocated by the hash table is released.
181 * This function is MT-safe and may be called from any thread.
186 g_hash_table_unref (GHashTable *hash_table)
188 g_return_if_fail (hash_table != NULL);
189 g_return_if_fail (hash_table->ref_count > 0);
191 if (g_atomic_int_exchange_and_add (&hash_table->ref_count, -1) - 1 == 0)
195 for (i = 0; i < hash_table->size; i++)
196 g_hash_nodes_destroy (hash_table->nodes[i],
197 hash_table->key_destroy_func,
198 hash_table->value_destroy_func);
199 g_free (hash_table->nodes);
200 g_slice_free (GHashTable, hash_table);
205 * g_hash_table_destroy:
206 * @hash_table: a #GHashTable.
208 * Destroys all keys and values in the #GHashTable and decrements its
209 * reference count by 1. If keys and/or values are dynamically allocated,
210 * you should either free them first or create the #GHashTable with destroy
211 * notifiers using g_hash_table_new_full(). In the latter case the destroy
212 * functions you supplied will be called on all keys and values during the
216 g_hash_table_destroy (GHashTable *hash_table)
218 g_return_if_fail (hash_table != NULL);
219 g_return_if_fail (hash_table->ref_count > 0);
221 g_hash_table_remove_all (hash_table);
222 g_hash_table_unref (hash_table);
225 static inline GHashNode**
226 g_hash_table_lookup_node (GHashTable *hash_table,
231 node = &hash_table->nodes
232 [(* hash_table->hash_func) (key) % hash_table->size];
234 /* Hash table lookup needs to be fast.
235 * We therefore remove the extra conditional of testing
236 * whether to call the key_equal_func or not from
239 if (hash_table->key_equal_func)
240 while (*node && !(*hash_table->key_equal_func) ((*node)->key, key))
241 node = &(*node)->next;
243 while (*node && (*node)->key != key)
244 node = &(*node)->next;
250 * g_hash_table_lookup:
251 * @hash_table: a #GHashTable.
252 * @key: the key to look up.
254 * Looks up a key in a #GHashTable. Note that this function cannot
255 * distinguish between a key that is not present and one which is present
256 * and has the value %NULL. If you need this distinction, use
257 * g_hash_table_lookup_extended().
259 * Return value: the associated value, or %NULL if the key is not found.
262 g_hash_table_lookup (GHashTable *hash_table,
267 g_return_val_if_fail (hash_table != NULL, NULL);
269 node = *g_hash_table_lookup_node (hash_table, key);
271 return node ? node->value : NULL;
275 * g_hash_table_lookup_extended:
276 * @hash_table: a #GHashTable.
277 * @lookup_key: the key to look up.
278 * @orig_key: returns the original key.
279 * @value: returns the value associated with the key.
281 * Looks up a key in the #GHashTable, returning the original key and the
282 * associated value and a #gboolean which is %TRUE if the key was found. This
283 * is useful if you need to free the memory allocated for the original key,
284 * for example before calling g_hash_table_remove().
286 * Return value: %TRUE if the key was found in the #GHashTable.
289 g_hash_table_lookup_extended (GHashTable *hash_table,
290 gconstpointer lookup_key,
296 g_return_val_if_fail (hash_table != NULL, FALSE);
298 node = *g_hash_table_lookup_node (hash_table, lookup_key);
303 *orig_key = node->key;
305 *value = node->value;
313 * g_hash_table_insert:
314 * @hash_table: a #GHashTable.
315 * @key: a key to insert.
316 * @value: the value to associate with the key.
318 * Inserts a new key and value into a #GHashTable.
320 * If the key already exists in the #GHashTable its current value is replaced
321 * with the new value. If you supplied a @value_destroy_func when creating the
322 * #GHashTable, the old value is freed using that function. If you supplied
323 * a @key_destroy_func when creating the #GHashTable, the passed key is freed
324 * using that function.
327 g_hash_table_insert (GHashTable *hash_table,
333 g_return_if_fail (hash_table != NULL);
334 g_return_if_fail (hash_table->ref_count > 0);
336 node = g_hash_table_lookup_node (hash_table, key);
340 /* do not reset node->key in this place, keeping
341 * the old key is the intended behaviour.
342 * g_hash_table_replace() can be used instead.
345 /* free the passed key */
346 if (hash_table->key_destroy_func)
347 hash_table->key_destroy_func (key);
349 if (hash_table->value_destroy_func)
350 hash_table->value_destroy_func ((*node)->value);
352 (*node)->value = value;
356 *node = g_hash_node_new (key, value);
357 hash_table->nnodes++;
358 G_HASH_TABLE_RESIZE (hash_table);
363 * g_hash_table_replace:
364 * @hash_table: a #GHashTable.
365 * @key: a key to insert.
366 * @value: the value to associate with the key.
368 * Inserts a new key and value into a #GHashTable similar to
369 * g_hash_table_insert(). The difference is that if the key already exists
370 * in the #GHashTable, it gets replaced by the new key. If you supplied a
371 * @value_destroy_func when creating the #GHashTable, the old value is freed
372 * using that function. If you supplied a @key_destroy_func when creating the
373 * #GHashTable, the old key is freed using that function.
376 g_hash_table_replace (GHashTable *hash_table,
382 g_return_if_fail (hash_table != NULL);
383 g_return_if_fail (hash_table->ref_count > 0);
385 node = g_hash_table_lookup_node (hash_table, key);
389 if (hash_table->key_destroy_func)
390 hash_table->key_destroy_func ((*node)->key);
392 if (hash_table->value_destroy_func)
393 hash_table->value_destroy_func ((*node)->value);
396 (*node)->value = value;
400 *node = g_hash_node_new (key, value);
401 hash_table->nnodes++;
402 G_HASH_TABLE_RESIZE (hash_table);
407 * g_hash_table_remove:
408 * @hash_table: a #GHashTable.
409 * @key: the key to remove.
411 * Removes a key and its associated value from a #GHashTable.
413 * If the #GHashTable was created using g_hash_table_new_full(), the
414 * key and value are freed using the supplied destroy functions, otherwise
415 * you have to make sure that any dynamically allocated values are freed
418 * Return value: %TRUE if the key was found and removed from the #GHashTable.
421 g_hash_table_remove (GHashTable *hash_table,
424 GHashNode **node, *dest;
426 g_return_val_if_fail (hash_table != NULL, FALSE);
428 node = g_hash_table_lookup_node (hash_table, key);
432 (*node) = dest->next;
433 g_hash_node_destroy (dest,
434 hash_table->key_destroy_func,
435 hash_table->value_destroy_func);
436 hash_table->nnodes--;
438 G_HASH_TABLE_RESIZE (hash_table);
447 * g_hash_table_remove_all:
448 * @hash_table: a #GHashTable
450 * Removes all keys and their associated values from a #GHashTable.
452 * If the #GHashTable was created using g_hash_table_new_full(), the keys
453 * and values are freed using the supplied destroy functions, otherwise you
454 * have to make sure that any dynamically allocated values are freed
460 g_hash_table_remove_all (GHashTable *hash_table)
464 g_return_if_fail (hash_table != NULL);
466 for (i = 0; i < hash_table->size; i++)
468 g_hash_nodes_destroy (hash_table->nodes[i],
469 hash_table->key_destroy_func,
470 hash_table->value_destroy_func);
471 hash_table->nodes[i] = NULL;
473 hash_table->nnodes = 0;
475 G_HASH_TABLE_RESIZE (hash_table);
479 * g_hash_table_steal:
480 * @hash_table: a #GHashTable.
481 * @key: the key to remove.
483 * Removes a key and its associated value from a #GHashTable without
484 * calling the key and value destroy functions.
486 * Return value: %TRUE if the key was found and removed from the #GHashTable.
489 g_hash_table_steal (GHashTable *hash_table,
492 GHashNode **node, *dest;
494 g_return_val_if_fail (hash_table != NULL, FALSE);
496 node = g_hash_table_lookup_node (hash_table, key);
500 (*node) = dest->next;
501 g_hash_node_destroy (dest, NULL, NULL);
502 hash_table->nnodes--;
504 G_HASH_TABLE_RESIZE (hash_table);
513 * g_hash_table_steal_all:
514 * @hash_table: a #GHashTable.
516 * Removes all keys and their associated values from a #GHashTable
517 * without calling the key and value destroy functions.
522 g_hash_table_steal_all (GHashTable *hash_table)
526 g_return_if_fail (hash_table != NULL);
528 for (i = 0; i < hash_table->size; i++)
530 g_hash_nodes_destroy (hash_table->nodes[i], NULL, NULL);
531 hash_table->nodes[i] = NULL;
534 hash_table->nnodes = 0;
536 G_HASH_TABLE_RESIZE (hash_table);
540 * g_hash_table_foreach_remove:
541 * @hash_table: a #GHashTable.
542 * @func: the function to call for each key/value pair.
543 * @user_data: user data to pass to the function.
545 * Calls the given function for each key/value pair in the #GHashTable.
546 * If the function returns %TRUE, then the key/value pair is removed from the
547 * #GHashTable. If you supplied key or value destroy functions when creating
548 * the #GHashTable, they are used to free the memory allocated for the removed
551 * Return value: the number of key/value pairs removed.
554 g_hash_table_foreach_remove (GHashTable *hash_table,
558 g_return_val_if_fail (hash_table != NULL, 0);
559 g_return_val_if_fail (func != NULL, 0);
561 return g_hash_table_foreach_remove_or_steal (hash_table, func, user_data, TRUE);
565 * g_hash_table_foreach_steal:
566 * @hash_table: a #GHashTable.
567 * @func: the function to call for each key/value pair.
568 * @user_data: user data to pass to the function.
570 * Calls the given function for each key/value pair in the #GHashTable.
571 * If the function returns %TRUE, then the key/value pair is removed from the
572 * #GHashTable, but no key or value destroy functions are called.
574 * Return value: the number of key/value pairs removed.
577 g_hash_table_foreach_steal (GHashTable *hash_table,
581 g_return_val_if_fail (hash_table != NULL, 0);
582 g_return_val_if_fail (func != NULL, 0);
584 return g_hash_table_foreach_remove_or_steal (hash_table, func, user_data, FALSE);
588 g_hash_table_foreach_remove_or_steal (GHashTable *hash_table,
593 GHashNode *node, *prev;
597 for (i = 0; i < hash_table->size; i++)
603 for (node = hash_table->nodes[i]; node; prev = node, node = node->next)
605 if ((* func) (node->key, node->value, user_data))
609 hash_table->nnodes -= 1;
613 prev->next = node->next;
614 g_hash_node_destroy (node,
615 notify ? hash_table->key_destroy_func : NULL,
616 notify ? hash_table->value_destroy_func : NULL);
621 hash_table->nodes[i] = node->next;
622 g_hash_node_destroy (node,
623 notify ? hash_table->key_destroy_func : NULL,
624 notify ? hash_table->value_destroy_func : NULL);
631 G_HASH_TABLE_RESIZE (hash_table);
637 * g_hash_table_foreach:
638 * @hash_table: a #GHashTable.
639 * @func: the function to call for each key/value pair.
640 * @user_data: user data to pass to the function.
642 * Calls the given function for each of the key/value pairs in the
643 * #GHashTable. The function is passed the key and value of each
644 * pair, and the given @user_data parameter. The hash table may not
645 * be modified while iterating over it (you can't add/remove
646 * items). To remove all items matching a predicate, use
647 * g_hash_table_foreach_remove().
650 g_hash_table_foreach (GHashTable *hash_table,
657 g_return_if_fail (hash_table != NULL);
658 g_return_if_fail (func != NULL);
660 for (i = 0; i < hash_table->size; i++)
661 for (node = hash_table->nodes[i]; node; node = node->next)
662 (* func) (node->key, node->value, user_data);
667 * @hash_table: a #GHashTable.
668 * @predicate: function to test the key/value pairs for a certain property.
669 * @user_data: user data to pass to the function.
671 * Calls the given function for key/value pairs in the #GHashTable until
672 * @predicate returns %TRUE. The function is passed the key and value of
673 * each pair, and the given @user_data parameter. The hash table may not
674 * be modified while iterating over it (you can't add/remove items).
676 * Return value: The value of the first key/value pair is returned, for which
677 * func evaluates to %TRUE. If no pair with the requested property is found,
683 g_hash_table_find (GHashTable *hash_table,
690 g_return_val_if_fail (hash_table != NULL, NULL);
691 g_return_val_if_fail (predicate != NULL, NULL);
693 for (i = 0; i < hash_table->size; i++)
694 for (node = hash_table->nodes[i]; node; node = node->next)
695 if (predicate (node->key, node->value, user_data))
702 * @hash_table: a #GHashTable.
704 * Returns the number of elements contained in the #GHashTable.
706 * Return value: the number of key/value pairs in the #GHashTable.
709 g_hash_table_size (GHashTable *hash_table)
711 g_return_val_if_fail (hash_table != NULL, 0);
713 return hash_table->nnodes;
717 g_hash_table_resize (GHashTable *hash_table)
719 GHashNode **new_nodes;
726 new_size = g_spaced_primes_closest (hash_table->nnodes);
727 new_size = CLAMP (new_size, HASH_TABLE_MIN_SIZE, HASH_TABLE_MAX_SIZE);
729 new_nodes = g_new0 (GHashNode*, new_size);
731 for (i = 0; i < hash_table->size; i++)
732 for (node = hash_table->nodes[i]; node; node = next)
736 hash_val = (* hash_table->hash_func) (node->key) % new_size;
738 node->next = new_nodes[hash_val];
739 new_nodes[hash_val] = node;
742 g_free (hash_table->nodes);
743 hash_table->nodes = new_nodes;
744 hash_table->size = new_size;
748 g_hash_node_new (gpointer key,
751 GHashNode *hash_node = g_slice_new (GHashNode);
753 hash_node->key = key;
754 hash_node->value = value;
755 hash_node->next = NULL;
761 g_hash_node_destroy (GHashNode *hash_node,
762 GDestroyNotify key_destroy_func,
763 GDestroyNotify value_destroy_func)
765 if (key_destroy_func)
766 key_destroy_func (hash_node->key);
767 if (value_destroy_func)
768 value_destroy_func (hash_node->value);
769 g_slice_free (GHashNode, hash_node);
773 g_hash_nodes_destroy (GHashNode *hash_node,
774 GFreeFunc key_destroy_func,
775 GFreeFunc value_destroy_func)
779 GHashNode *next = hash_node->next;
780 if (key_destroy_func)
781 key_destroy_func (hash_node->key);
782 if (value_destroy_func)
783 value_destroy_func (hash_node->value);
784 g_slice_free (GHashNode, hash_node);
791 #include "galiasdef.c"