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.
163 g_hash_table_ref (GHashTable *hash_table)
165 g_return_val_if_fail (hash_table != NULL, NULL);
166 g_return_val_if_fail (hash_table->ref_count > 0, hash_table);
168 g_atomic_int_add (&hash_table->ref_count, 1);
173 * g_hash_table_unref:
174 * @hash_table: a valid #GHashTable.
176 * Atomically decrements the reference count of @hash_table by one.
177 * If the reference count drops to 0, all keys and values will be
178 * destroyed, and all memory allocated by the hash table is released.
179 * This function is MT-safe and may be called from any thread.
182 g_hash_table_unref (GHashTable *hash_table)
184 g_return_if_fail (hash_table != NULL);
185 g_return_if_fail (hash_table->ref_count > 0);
187 if (g_atomic_int_exchange_and_add (&hash_table->ref_count, -1) - 1 == 0)
190 for (i = 0; i < hash_table->size; i++)
191 g_hash_nodes_destroy (hash_table->nodes[i],
192 hash_table->key_destroy_func,
193 hash_table->value_destroy_func);
194 g_free (hash_table->nodes);
195 g_slice_free (GHashTable, hash_table);
200 * g_hash_table_destroy:
201 * @hash_table: a #GHashTable.
203 * Destroys all keys and values in the #GHashTable and decrements it's
204 * reference count by 1. If keys and/or values are dynamically allocated,
205 * you should either free them first or create the #GHashTable with destroy
206 * notifiers using g_hash_table_new_full(). In the latter case the destroy
207 * functions you supplied will be called on all keys and values during the
211 g_hash_table_destroy (GHashTable *hash_table)
215 g_return_if_fail (hash_table != NULL);
216 g_return_if_fail (hash_table->ref_count > 0);
218 for (i = 0; i < hash_table->size; i++)
220 g_hash_nodes_destroy (hash_table->nodes[i],
221 hash_table->key_destroy_func,
222 hash_table->value_destroy_func);
223 hash_table->nodes[i] = NULL;
225 hash_table->nnodes = 0;
226 hash_table->size = HASH_TABLE_MIN_SIZE;
228 g_hash_table_unref (hash_table);
231 static inline GHashNode**
232 g_hash_table_lookup_node (GHashTable *hash_table,
237 node = &hash_table->nodes
238 [(* hash_table->hash_func) (key) % hash_table->size];
240 /* Hash table lookup needs to be fast.
241 * We therefore remove the extra conditional of testing
242 * whether to call the key_equal_func or not from
245 if (hash_table->key_equal_func)
246 while (*node && !(*hash_table->key_equal_func) ((*node)->key, key))
247 node = &(*node)->next;
249 while (*node && (*node)->key != key)
250 node = &(*node)->next;
256 * g_hash_table_lookup:
257 * @hash_table: a #GHashTable.
258 * @key: the key to look up.
260 * Looks up a key in a #GHashTable. Note that this function cannot
261 * distinguish between a key that is not present and one which is present
262 * and has the value %NULL. If you need this distinction, use
263 * g_hash_table_lookup_extended().
265 * Return value: the associated value, or %NULL if the key is not found.
268 g_hash_table_lookup (GHashTable *hash_table,
273 g_return_val_if_fail (hash_table != NULL, NULL);
275 node = *g_hash_table_lookup_node (hash_table, key);
277 return node ? node->value : NULL;
281 * g_hash_table_lookup_extended:
282 * @hash_table: a #GHashTable.
283 * @lookup_key: the key to look up.
284 * @orig_key: returns the original key.
285 * @value: returns the value associated with the key.
287 * Looks up a key in the #GHashTable, returning the original key and the
288 * associated value and a #gboolean which is %TRUE if the key was found. This
289 * is useful if you need to free the memory allocated for the original key,
290 * for example before calling g_hash_table_remove().
292 * Return value: %TRUE if the key was found in the #GHashTable.
295 g_hash_table_lookup_extended (GHashTable *hash_table,
296 gconstpointer lookup_key,
302 g_return_val_if_fail (hash_table != NULL, FALSE);
304 node = *g_hash_table_lookup_node (hash_table, lookup_key);
309 *orig_key = node->key;
311 *value = node->value;
319 * g_hash_table_insert:
320 * @hash_table: a #GHashTable.
321 * @key: a key to insert.
322 * @value: the value to associate with the key.
324 * Inserts a new key and value into a #GHashTable.
326 * If the key already exists in the #GHashTable its current value is replaced
327 * with the new value. If you supplied a @value_destroy_func when creating the
328 * #GHashTable, the old value is freed using that function. If you supplied
329 * a @key_destroy_func when creating the #GHashTable, the passed key is freed
330 * using that function.
333 g_hash_table_insert (GHashTable *hash_table,
339 g_return_if_fail (hash_table != NULL);
340 g_return_if_fail (hash_table->ref_count > 0);
342 node = g_hash_table_lookup_node (hash_table, key);
346 /* do not reset node->key in this place, keeping
347 * the old key is the intended behaviour.
348 * g_hash_table_replace() can be used instead.
351 /* free the passed key */
352 if (hash_table->key_destroy_func)
353 hash_table->key_destroy_func (key);
355 if (hash_table->value_destroy_func)
356 hash_table->value_destroy_func ((*node)->value);
358 (*node)->value = value;
362 *node = g_hash_node_new (key, value);
363 hash_table->nnodes++;
364 G_HASH_TABLE_RESIZE (hash_table);
369 * g_hash_table_replace:
370 * @hash_table: a #GHashTable.
371 * @key: a key to insert.
372 * @value: the value to associate with the key.
374 * Inserts a new key and value into a #GHashTable similar to
375 * g_hash_table_insert(). The difference is that if the key already exists
376 * in the #GHashTable, it gets replaced by the new key. If you supplied a
377 * @value_destroy_func when creating the #GHashTable, the old value is freed
378 * using that function. If you supplied a @key_destroy_func when creating the
379 * #GHashTable, the old key is freed using that function.
382 g_hash_table_replace (GHashTable *hash_table,
388 g_return_if_fail (hash_table != NULL);
389 g_return_if_fail (hash_table->ref_count > 0);
391 node = g_hash_table_lookup_node (hash_table, key);
395 if (hash_table->key_destroy_func)
396 hash_table->key_destroy_func ((*node)->key);
398 if (hash_table->value_destroy_func)
399 hash_table->value_destroy_func ((*node)->value);
402 (*node)->value = value;
406 *node = g_hash_node_new (key, value);
407 hash_table->nnodes++;
408 G_HASH_TABLE_RESIZE (hash_table);
413 * g_hash_table_remove:
414 * @hash_table: a #GHashTable.
415 * @key: the key to remove.
417 * Removes a key and its associated value from a #GHashTable.
419 * If the #GHashTable was created using g_hash_table_new_full(), the
420 * key and value are freed using the supplied destroy functions, otherwise
421 * you have to make sure that any dynamically allocated values are freed
424 * Return value: %TRUE if the key was found and removed from the #GHashTable.
427 g_hash_table_remove (GHashTable *hash_table,
430 GHashNode **node, *dest;
432 g_return_val_if_fail (hash_table != NULL, FALSE);
434 node = g_hash_table_lookup_node (hash_table, key);
438 (*node) = dest->next;
439 g_hash_node_destroy (dest,
440 hash_table->key_destroy_func,
441 hash_table->value_destroy_func);
442 hash_table->nnodes--;
444 G_HASH_TABLE_RESIZE (hash_table);
453 * g_hash_table_steal:
454 * @hash_table: a #GHashTable.
455 * @key: the key to remove.
457 * Removes a key and its associated value from a #GHashTable without
458 * calling the key and value destroy functions.
460 * Return value: %TRUE if the key was found and removed from the #GHashTable.
463 g_hash_table_steal (GHashTable *hash_table,
466 GHashNode **node, *dest;
468 g_return_val_if_fail (hash_table != NULL, FALSE);
470 node = g_hash_table_lookup_node (hash_table, key);
474 (*node) = dest->next;
475 g_hash_node_destroy (dest, NULL, NULL);
476 hash_table->nnodes--;
478 G_HASH_TABLE_RESIZE (hash_table);
487 * g_hash_table_foreach_remove:
488 * @hash_table: a #GHashTable.
489 * @func: the function to call for each key/value pair.
490 * @user_data: user data to pass to the function.
492 * Calls the given function for each key/value pair in the #GHashTable.
493 * If the function returns %TRUE, then the key/value pair is removed from the
494 * #GHashTable. If you supplied key or value destroy functions when creating
495 * the #GHashTable, they are used to free the memory allocated for the removed
498 * Return value: the number of key/value pairs removed.
501 g_hash_table_foreach_remove (GHashTable *hash_table,
505 g_return_val_if_fail (hash_table != NULL, 0);
506 g_return_val_if_fail (func != NULL, 0);
508 return g_hash_table_foreach_remove_or_steal (hash_table, func, user_data, TRUE);
512 * g_hash_table_foreach_steal:
513 * @hash_table: a #GHashTable.
514 * @func: the function to call for each key/value pair.
515 * @user_data: user data to pass to the function.
517 * Calls the given function for each key/value pair in the #GHashTable.
518 * If the function returns %TRUE, then the key/value pair is removed from the
519 * #GHashTable, but no key or value destroy functions are called.
521 * Return value: the number of key/value pairs removed.
524 g_hash_table_foreach_steal (GHashTable *hash_table,
528 g_return_val_if_fail (hash_table != NULL, 0);
529 g_return_val_if_fail (func != NULL, 0);
531 return g_hash_table_foreach_remove_or_steal (hash_table, func, user_data, FALSE);
535 g_hash_table_foreach_remove_or_steal (GHashTable *hash_table,
540 GHashNode *node, *prev;
544 for (i = 0; i < hash_table->size; i++)
550 for (node = hash_table->nodes[i]; node; prev = node, node = node->next)
552 if ((* func) (node->key, node->value, user_data))
556 hash_table->nnodes -= 1;
560 prev->next = node->next;
561 g_hash_node_destroy (node,
562 notify ? hash_table->key_destroy_func : NULL,
563 notify ? hash_table->value_destroy_func : NULL);
568 hash_table->nodes[i] = node->next;
569 g_hash_node_destroy (node,
570 notify ? hash_table->key_destroy_func : NULL,
571 notify ? hash_table->value_destroy_func : NULL);
578 G_HASH_TABLE_RESIZE (hash_table);
584 * g_hash_table_foreach:
585 * @hash_table: a #GHashTable.
586 * @func: the function to call for each key/value pair.
587 * @user_data: user data to pass to the function.
589 * Calls the given function for each of the key/value pairs in the
590 * #GHashTable. The function is passed the key and value of each
591 * pair, and the given @user_data parameter. The hash table may not
592 * be modified while iterating over it (you can't add/remove
593 * items). To remove all items matching a predicate, use
594 * g_hash_table_foreach_remove().
597 g_hash_table_foreach (GHashTable *hash_table,
604 g_return_if_fail (hash_table != NULL);
605 g_return_if_fail (func != NULL);
607 for (i = 0; i < hash_table->size; i++)
608 for (node = hash_table->nodes[i]; node; node = node->next)
609 (* func) (node->key, node->value, user_data);
614 * @hash_table: a #GHashTable.
615 * @predicate: function to test the key/value pairs for a certain property.
616 * @user_data: user data to pass to the function.
618 * Calls the given function for key/value pairs in the #GHashTable until
619 * @predicate returns %TRUE. The function is passed the key and value of
620 * each pair, and the given @user_data parameter. The hash table may not
621 * be modified while iterating over it (you can't add/remove items).
623 * Return value: The value of the first key/value pair is returned, for which
624 * func evaluates to %TRUE. If no pair with the requested property is found,
630 g_hash_table_find (GHashTable *hash_table,
637 g_return_val_if_fail (hash_table != NULL, NULL);
638 g_return_val_if_fail (predicate != NULL, NULL);
640 for (i = 0; i < hash_table->size; i++)
641 for (node = hash_table->nodes[i]; node; node = node->next)
642 if (predicate (node->key, node->value, user_data))
649 * @hash_table: a #GHashTable.
651 * Returns the number of elements contained in the #GHashTable.
653 * Return value: the number of key/value pairs in the #GHashTable.
656 g_hash_table_size (GHashTable *hash_table)
658 g_return_val_if_fail (hash_table != NULL, 0);
660 return hash_table->nnodes;
664 g_hash_table_resize (GHashTable *hash_table)
666 GHashNode **new_nodes;
673 new_size = g_spaced_primes_closest (hash_table->nnodes);
674 new_size = CLAMP (new_size, HASH_TABLE_MIN_SIZE, HASH_TABLE_MAX_SIZE);
676 new_nodes = g_new0 (GHashNode*, new_size);
678 for (i = 0; i < hash_table->size; i++)
679 for (node = hash_table->nodes[i]; node; node = next)
683 hash_val = (* hash_table->hash_func) (node->key) % new_size;
685 node->next = new_nodes[hash_val];
686 new_nodes[hash_val] = node;
689 g_free (hash_table->nodes);
690 hash_table->nodes = new_nodes;
691 hash_table->size = new_size;
695 g_hash_node_new (gpointer key,
698 GHashNode *hash_node = g_slice_new (GHashNode);
700 hash_node->key = key;
701 hash_node->value = value;
702 hash_node->next = NULL;
708 g_hash_node_destroy (GHashNode *hash_node,
709 GDestroyNotify key_destroy_func,
710 GDestroyNotify value_destroy_func)
712 if (key_destroy_func)
713 key_destroy_func (hash_node->key);
714 if (value_destroy_func)
715 value_destroy_func (hash_node->value);
717 #ifdef ENABLE_GC_FRIENDLY
718 hash_node->key = NULL;
719 hash_node->value = NULL;
720 #endif /* ENABLE_GC_FRIENDLY */
722 g_slice_free (GHashNode, hash_node);
726 g_hash_nodes_destroy (GHashNode *hash_node,
727 GFreeFunc key_destroy_func,
728 GFreeFunc value_destroy_func)
732 GHashNode *next = hash_node->next;
733 if (key_destroy_func)
734 key_destroy_func (hash_node->key);
735 if (value_destroy_func)
736 value_destroy_func (hash_node->value);
737 g_slice_free (GHashNode, hash_node);
744 #include "galiasdef.c"