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 guint 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)
194 for (i = 0; i < hash_table->size; i++)
195 g_hash_nodes_destroy (hash_table->nodes[i],
196 hash_table->key_destroy_func,
197 hash_table->value_destroy_func);
198 g_free (hash_table->nodes);
199 g_slice_free (GHashTable, hash_table);
204 * g_hash_table_destroy:
205 * @hash_table: a #GHashTable.
207 * Destroys all keys and values in the #GHashTable and decrements its
208 * reference count by 1. If keys and/or values are dynamically allocated,
209 * you should either free them first or create the #GHashTable with destroy
210 * notifiers using g_hash_table_new_full(). In the latter case the destroy
211 * functions you supplied will be called on all keys and values during the
215 g_hash_table_destroy (GHashTable *hash_table)
219 g_return_if_fail (hash_table != NULL);
220 g_return_if_fail (hash_table->ref_count > 0);
222 for (i = 0; i < hash_table->size; i++)
224 g_hash_nodes_destroy (hash_table->nodes[i],
225 hash_table->key_destroy_func,
226 hash_table->value_destroy_func);
227 hash_table->nodes[i] = NULL;
229 hash_table->nnodes = 0;
230 hash_table->size = HASH_TABLE_MIN_SIZE;
232 g_hash_table_unref (hash_table);
235 static inline GHashNode**
236 g_hash_table_lookup_node (GHashTable *hash_table,
241 node = &hash_table->nodes
242 [(* hash_table->hash_func) (key) % hash_table->size];
244 /* Hash table lookup needs to be fast.
245 * We therefore remove the extra conditional of testing
246 * whether to call the key_equal_func or not from
249 if (hash_table->key_equal_func)
250 while (*node && !(*hash_table->key_equal_func) ((*node)->key, key))
251 node = &(*node)->next;
253 while (*node && (*node)->key != key)
254 node = &(*node)->next;
260 * g_hash_table_lookup:
261 * @hash_table: a #GHashTable.
262 * @key: the key to look up.
264 * Looks up a key in a #GHashTable. Note that this function cannot
265 * distinguish between a key that is not present and one which is present
266 * and has the value %NULL. If you need this distinction, use
267 * g_hash_table_lookup_extended().
269 * Return value: the associated value, or %NULL if the key is not found.
272 g_hash_table_lookup (GHashTable *hash_table,
277 g_return_val_if_fail (hash_table != NULL, NULL);
279 node = *g_hash_table_lookup_node (hash_table, key);
281 return node ? node->value : NULL;
285 * g_hash_table_lookup_extended:
286 * @hash_table: a #GHashTable.
287 * @lookup_key: the key to look up.
288 * @orig_key: returns the original key.
289 * @value: returns the value associated with the key.
291 * Looks up a key in the #GHashTable, returning the original key and the
292 * associated value and a #gboolean which is %TRUE if the key was found. This
293 * is useful if you need to free the memory allocated for the original key,
294 * for example before calling g_hash_table_remove().
296 * Return value: %TRUE if the key was found in the #GHashTable.
299 g_hash_table_lookup_extended (GHashTable *hash_table,
300 gconstpointer lookup_key,
306 g_return_val_if_fail (hash_table != NULL, FALSE);
308 node = *g_hash_table_lookup_node (hash_table, lookup_key);
313 *orig_key = node->key;
315 *value = node->value;
323 * g_hash_table_insert:
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.
330 * If the key already exists in the #GHashTable its current value is replaced
331 * with the new value. If you supplied a @value_destroy_func when creating the
332 * #GHashTable, the old value is freed using that function. If you supplied
333 * a @key_destroy_func when creating the #GHashTable, the passed key is freed
334 * using that function.
337 g_hash_table_insert (GHashTable *hash_table,
343 g_return_if_fail (hash_table != NULL);
344 g_return_if_fail (hash_table->ref_count > 0);
346 node = g_hash_table_lookup_node (hash_table, key);
350 /* do not reset node->key in this place, keeping
351 * the old key is the intended behaviour.
352 * g_hash_table_replace() can be used instead.
355 /* free the passed key */
356 if (hash_table->key_destroy_func)
357 hash_table->key_destroy_func (key);
359 if (hash_table->value_destroy_func)
360 hash_table->value_destroy_func ((*node)->value);
362 (*node)->value = value;
366 *node = g_hash_node_new (key, value);
367 hash_table->nnodes++;
368 G_HASH_TABLE_RESIZE (hash_table);
373 * g_hash_table_replace:
374 * @hash_table: a #GHashTable.
375 * @key: a key to insert.
376 * @value: the value to associate with the key.
378 * Inserts a new key and value into a #GHashTable similar to
379 * g_hash_table_insert(). The difference is that if the key already exists
380 * in the #GHashTable, it gets replaced by the new key. If you supplied a
381 * @value_destroy_func when creating the #GHashTable, the old value is freed
382 * using that function. If you supplied a @key_destroy_func when creating the
383 * #GHashTable, the old key is freed using that function.
386 g_hash_table_replace (GHashTable *hash_table,
392 g_return_if_fail (hash_table != NULL);
393 g_return_if_fail (hash_table->ref_count > 0);
395 node = g_hash_table_lookup_node (hash_table, key);
399 if (hash_table->key_destroy_func)
400 hash_table->key_destroy_func ((*node)->key);
402 if (hash_table->value_destroy_func)
403 hash_table->value_destroy_func ((*node)->value);
406 (*node)->value = value;
410 *node = g_hash_node_new (key, value);
411 hash_table->nnodes++;
412 G_HASH_TABLE_RESIZE (hash_table);
417 * g_hash_table_remove:
418 * @hash_table: a #GHashTable.
419 * @key: the key to remove.
421 * Removes a key and its associated value from a #GHashTable.
423 * If the #GHashTable was created using g_hash_table_new_full(), the
424 * key and value are freed using the supplied destroy functions, otherwise
425 * you have to make sure that any dynamically allocated values are freed
428 * Return value: %TRUE if the key was found and removed from the #GHashTable.
431 g_hash_table_remove (GHashTable *hash_table,
434 GHashNode **node, *dest;
436 g_return_val_if_fail (hash_table != NULL, FALSE);
438 node = g_hash_table_lookup_node (hash_table, key);
442 (*node) = dest->next;
443 g_hash_node_destroy (dest,
444 hash_table->key_destroy_func,
445 hash_table->value_destroy_func);
446 hash_table->nnodes--;
448 G_HASH_TABLE_RESIZE (hash_table);
457 * g_hash_table_steal:
458 * @hash_table: a #GHashTable.
459 * @key: the key to remove.
461 * Removes a key and its associated value from a #GHashTable without
462 * calling the key and value destroy functions.
464 * Return value: %TRUE if the key was found and removed from the #GHashTable.
467 g_hash_table_steal (GHashTable *hash_table,
470 GHashNode **node, *dest;
472 g_return_val_if_fail (hash_table != NULL, FALSE);
474 node = g_hash_table_lookup_node (hash_table, key);
478 (*node) = dest->next;
479 g_hash_node_destroy (dest, NULL, NULL);
480 hash_table->nnodes--;
482 G_HASH_TABLE_RESIZE (hash_table);
491 * g_hash_table_foreach_remove:
492 * @hash_table: a #GHashTable.
493 * @func: the function to call for each key/value pair.
494 * @user_data: user data to pass to the function.
496 * Calls the given function for each key/value pair in the #GHashTable.
497 * If the function returns %TRUE, then the key/value pair is removed from the
498 * #GHashTable. If you supplied key or value destroy functions when creating
499 * the #GHashTable, they are used to free the memory allocated for the removed
502 * Return value: the number of key/value pairs removed.
505 g_hash_table_foreach_remove (GHashTable *hash_table,
509 g_return_val_if_fail (hash_table != NULL, 0);
510 g_return_val_if_fail (func != NULL, 0);
512 return g_hash_table_foreach_remove_or_steal (hash_table, func, user_data, TRUE);
516 * g_hash_table_foreach_steal:
517 * @hash_table: a #GHashTable.
518 * @func: the function to call for each key/value pair.
519 * @user_data: user data to pass to the function.
521 * Calls the given function for each key/value pair in the #GHashTable.
522 * If the function returns %TRUE, then the key/value pair is removed from the
523 * #GHashTable, but no key or value destroy functions are called.
525 * Return value: the number of key/value pairs removed.
528 g_hash_table_foreach_steal (GHashTable *hash_table,
532 g_return_val_if_fail (hash_table != NULL, 0);
533 g_return_val_if_fail (func != NULL, 0);
535 return g_hash_table_foreach_remove_or_steal (hash_table, func, user_data, FALSE);
539 g_hash_table_foreach_remove_or_steal (GHashTable *hash_table,
544 GHashNode *node, *prev;
548 for (i = 0; i < hash_table->size; i++)
554 for (node = hash_table->nodes[i]; node; prev = node, node = node->next)
556 if ((* func) (node->key, node->value, user_data))
560 hash_table->nnodes -= 1;
564 prev->next = node->next;
565 g_hash_node_destroy (node,
566 notify ? hash_table->key_destroy_func : NULL,
567 notify ? hash_table->value_destroy_func : NULL);
572 hash_table->nodes[i] = node->next;
573 g_hash_node_destroy (node,
574 notify ? hash_table->key_destroy_func : NULL,
575 notify ? hash_table->value_destroy_func : NULL);
582 G_HASH_TABLE_RESIZE (hash_table);
588 * g_hash_table_foreach:
589 * @hash_table: a #GHashTable.
590 * @func: the function to call for each key/value pair.
591 * @user_data: user data to pass to the function.
593 * Calls the given function for each of the key/value pairs in the
594 * #GHashTable. The function is passed the key and value of each
595 * pair, and the given @user_data parameter. The hash table may not
596 * be modified while iterating over it (you can't add/remove
597 * items). To remove all items matching a predicate, use
598 * g_hash_table_foreach_remove().
601 g_hash_table_foreach (GHashTable *hash_table,
608 g_return_if_fail (hash_table != NULL);
609 g_return_if_fail (func != NULL);
611 for (i = 0; i < hash_table->size; i++)
612 for (node = hash_table->nodes[i]; node; node = node->next)
613 (* func) (node->key, node->value, user_data);
618 * @hash_table: a #GHashTable.
619 * @predicate: function to test the key/value pairs for a certain property.
620 * @user_data: user data to pass to the function.
622 * Calls the given function for key/value pairs in the #GHashTable until
623 * @predicate returns %TRUE. The function is passed the key and value of
624 * each pair, and the given @user_data parameter. The hash table may not
625 * be modified while iterating over it (you can't add/remove items).
627 * Return value: The value of the first key/value pair is returned, for which
628 * func evaluates to %TRUE. If no pair with the requested property is found,
634 g_hash_table_find (GHashTable *hash_table,
641 g_return_val_if_fail (hash_table != NULL, NULL);
642 g_return_val_if_fail (predicate != NULL, NULL);
644 for (i = 0; i < hash_table->size; i++)
645 for (node = hash_table->nodes[i]; node; node = node->next)
646 if (predicate (node->key, node->value, user_data))
653 * @hash_table: a #GHashTable.
655 * Returns the number of elements contained in the #GHashTable.
657 * Return value: the number of key/value pairs in the #GHashTable.
660 g_hash_table_size (GHashTable *hash_table)
662 g_return_val_if_fail (hash_table != NULL, 0);
664 return hash_table->nnodes;
668 g_hash_table_resize (GHashTable *hash_table)
670 GHashNode **new_nodes;
677 new_size = g_spaced_primes_closest (hash_table->nnodes);
678 new_size = CLAMP (new_size, HASH_TABLE_MIN_SIZE, HASH_TABLE_MAX_SIZE);
680 new_nodes = g_new0 (GHashNode*, new_size);
682 for (i = 0; i < hash_table->size; i++)
683 for (node = hash_table->nodes[i]; node; node = next)
687 hash_val = (* hash_table->hash_func) (node->key) % new_size;
689 node->next = new_nodes[hash_val];
690 new_nodes[hash_val] = node;
693 g_free (hash_table->nodes);
694 hash_table->nodes = new_nodes;
695 hash_table->size = new_size;
699 g_hash_node_new (gpointer key,
702 GHashNode *hash_node = g_slice_new (GHashNode);
704 hash_node->key = key;
705 hash_node->value = value;
706 hash_node->next = NULL;
712 g_hash_node_destroy (GHashNode *hash_node,
713 GDestroyNotify key_destroy_func,
714 GDestroyNotify value_destroy_func)
716 if (key_destroy_func)
717 key_destroy_func (hash_node->key);
718 if (value_destroy_func)
719 value_destroy_func (hash_node->value);
721 #ifdef ENABLE_GC_FRIENDLY
722 hash_node->key = NULL;
723 hash_node->value = NULL;
724 #endif /* ENABLE_GC_FRIENDLY */
726 g_slice_free (GHashNode, hash_node);
730 g_hash_nodes_destroy (GHashNode *hash_node,
731 GFreeFunc key_destroy_func,
732 GFreeFunc value_destroy_func)
736 GHashNode *next = hash_node->next;
737 if (key_destroy_func)
738 key_destroy_func (hash_node->key);
739 if (value_destroy_func)
740 value_destroy_func (hash_node->value);
741 g_slice_free (GHashNode, hash_node);
748 #include "galiasdef.c"