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/.
33 #include <string.h> /* memset */
38 #define HASH_TABLE_MIN_SHIFT 3 /* 1 << 3 == 8 buckets */
40 typedef struct _GHashNode GHashNode;
47 /* If key_hash == 0, node is not in use
48 * If key_hash == 1, node is a tombstone
49 * If key_hash >= 2, node contains data */
59 gint noccupied; /* nnodes + tombstones */
62 GEqualFunc key_equal_func;
63 volatile gint ref_count;
64 #ifndef G_DISABLE_ASSERT
66 * Tracks the structure of the hash table, not its contents: is only
67 * incremented when a node is added or removed (is not incremented
68 * when the key or data of a node is modified).
72 GDestroyNotify key_destroy_func;
73 GDestroyNotify value_destroy_func;
78 GHashTable *hash_table;
86 /* Each table size has an associated prime modulo (the first prime
87 * lower than the table size) used to find the initial bucket. Probing
88 * then works modulo 2^n. The prime modulo is necessary to get a
89 * good distribution with poor hash functions. */
90 static const gint prime_mod [] =
108 65521, /* For 1 << 16 */
123 2147483647 /* For 1 << 31 */
127 g_hash_table_set_shift (GHashTable *hash_table, gint shift)
132 hash_table->size = 1 << shift;
133 hash_table->mod = prime_mod [shift];
135 for (i = 0; i < shift; i++)
141 hash_table->mask = mask;
145 g_hash_table_find_closest_shift (gint n)
156 g_hash_table_set_shift_from_size (GHashTable *hash_table, gint size)
160 shift = g_hash_table_find_closest_shift (size);
161 shift = MAX (shift, HASH_TABLE_MIN_SHIFT);
163 g_hash_table_set_shift (hash_table, shift);
167 * g_hash_table_lookup_node:
168 * @hash_table: our #GHashTable
169 * @key: the key to lookup against
170 * @hash_return: optional key hash return location
171 * Return value: index of the described #GHashNode
173 * Performs a lookup in the hash table. Virtually all hash operations
174 * will use this function internally.
176 * This function first computes the hash value of the key using the
177 * user's hash function.
179 * If an entry in the table matching @key is found then this function
180 * returns the index of that entry in the table, and if not, the
181 * index of an empty node (never a tombstone).
184 g_hash_table_lookup_node (GHashTable *hash_table,
192 /* Empty buckets have hash_value set to 0, and for tombstones, it's 1.
193 * We need to make sure our hash value is not one of these. */
195 hash_value = (* hash_table->hash_func) (key);
196 if (G_UNLIKELY (hash_value <= 1))
199 node_index = hash_value % hash_table->mod;
200 node = &hash_table->nodes [node_index];
202 while (node->key_hash)
204 /* We first check if our full hash values
205 * are equal so we can avoid calling the full-blown
206 * key equality function in most cases.
209 if (node->key_hash == hash_value)
211 if (hash_table->key_equal_func)
213 if (hash_table->key_equal_func (node->key, key))
216 else if (node->key == key)
224 node_index &= hash_table->mask;
225 node = &hash_table->nodes [node_index];
232 * g_hash_table_lookup_node_for_insertion:
233 * @hash_table: our #GHashTable
234 * @key: the key to lookup against
235 * @hash_return: key hash return location
236 * Return value: index of the described #GHashNode
238 * Performs a lookup in the hash table, preserving extra information
239 * usually needed for insertion.
241 * This function first computes the hash value of the key using the
242 * user's hash function.
244 * If an entry in the table matching @key is found then this function
245 * returns the index of that entry in the table, and if not, the
246 * index of an unused node (empty or tombstone) where the key can be
249 * The computed hash value is returned in the variable pointed to
250 * by @hash_return. This is to save insertions from having to compute
251 * the hash record again for the new record.
254 g_hash_table_lookup_node_for_insertion (GHashTable *hash_table,
261 guint first_tombstone;
262 gboolean have_tombstone = FALSE;
265 /* Empty buckets have hash_value set to 0, and for tombstones, it's 1.
266 * We need to make sure our hash value is not one of these. */
268 hash_value = (* hash_table->hash_func) (key);
269 if (G_UNLIKELY (hash_value <= 1))
272 *hash_return = hash_value;
274 node_index = hash_value % hash_table->mod;
275 node = &hash_table->nodes [node_index];
277 while (node->key_hash)
279 /* We first check if our full hash values
280 * are equal so we can avoid calling the full-blown
281 * key equality function in most cases.
284 if (node->key_hash == hash_value)
286 if (hash_table->key_equal_func)
288 if (hash_table->key_equal_func (node->key, key))
291 else if (node->key == key)
296 else if (node->key_hash == 1 && !have_tombstone)
298 first_tombstone = node_index;
299 have_tombstone = TRUE;
304 node_index &= hash_table->mask;
305 node = &hash_table->nodes [node_index];
309 return first_tombstone;
315 * g_hash_table_remove_node:
316 * @hash_table: our #GHashTable
317 * @node: pointer to node to remove
318 * @notify: %TRUE if the destroy notify handlers are to be called
320 * Removes a node from the hash table and updates the node count.
321 * The node is replaced by a tombstone. No table resize is performed.
323 * If @notify is %TRUE then the destroy notify functions are called
324 * for the key and value of the hash node.
327 g_hash_table_remove_node (GHashTable *hash_table,
331 if (notify && hash_table->key_destroy_func)
332 hash_table->key_destroy_func (node->key);
334 if (notify && hash_table->value_destroy_func)
335 hash_table->value_destroy_func (node->value);
337 /* Erect tombstone */
344 hash_table->nnodes--;
348 * g_hash_table_remove_all_nodes:
349 * @hash_table: our #GHashTable
350 * @notify: %TRUE if the destroy notify handlers are to be called
352 * Removes all nodes from the table. Since this may be a precursor to
353 * freeing the table entirely, no resize is performed.
355 * If @notify is %TRUE then the destroy notify functions are called
356 * for the key and value of the hash node.
359 g_hash_table_remove_all_nodes (GHashTable *hash_table,
364 for (i = 0; i < hash_table->size; i++)
366 GHashNode *node = &hash_table->nodes [i];
368 if (node->key_hash > 1)
370 if (notify && hash_table->key_destroy_func)
371 hash_table->key_destroy_func (node->key);
373 if (notify && hash_table->value_destroy_func)
374 hash_table->value_destroy_func (node->value);
378 /* We need to set node->key_hash = 0 for all nodes - might as well be GC
379 * friendly and clear everything */
380 memset (hash_table->nodes, 0, hash_table->size * sizeof (GHashNode));
382 hash_table->nnodes = 0;
383 hash_table->noccupied = 0;
387 * g_hash_table_resize:
388 * @hash_table: our #GHashTable
390 * Resizes the hash table to the optimal size based on the number of
391 * nodes currently held. If you call this function then a resize will
392 * occur, even if one does not need to occur. Use
393 * g_hash_table_maybe_resize() instead.
395 * This function may "resize" the hash table to its current size, with
396 * the side effect of cleaning up tombstones and otherwise optimizing
397 * the probe sequences.
400 g_hash_table_resize (GHashTable *hash_table)
402 GHashNode *new_nodes;
406 old_size = hash_table->size;
407 g_hash_table_set_shift_from_size (hash_table, hash_table->nnodes * 2);
409 new_nodes = g_new0 (GHashNode, hash_table->size);
411 for (i = 0; i < old_size; i++)
413 GHashNode *node = &hash_table->nodes [i];
418 if (node->key_hash <= 1)
421 hash_val = node->key_hash % hash_table->mod;
422 new_node = &new_nodes [hash_val];
424 while (new_node->key_hash)
428 hash_val &= hash_table->mask;
429 new_node = &new_nodes [hash_val];
435 g_free (hash_table->nodes);
436 hash_table->nodes = new_nodes;
437 hash_table->noccupied = hash_table->nnodes;
441 * g_hash_table_maybe_resize:
442 * @hash_table: our #GHashTable
444 * Resizes the hash table, if needed.
446 * Essentially, calls g_hash_table_resize() if the table has strayed
447 * too far from its ideal size for its number of nodes.
450 g_hash_table_maybe_resize (GHashTable *hash_table)
452 gint noccupied = hash_table->noccupied;
453 gint size = hash_table->size;
455 if ((size > hash_table->nnodes * 4 && size > 1 << HASH_TABLE_MIN_SHIFT) ||
456 (size <= noccupied + (noccupied / 16)))
457 g_hash_table_resize (hash_table);
462 * @hash_func: a function to create a hash value from a key.
463 * Hash values are used to determine where keys are stored within the
464 * #GHashTable data structure. The g_direct_hash(), g_int_hash(),
465 * g_int64_hash(), g_double_hash() and g_str_hash() functions are provided
466 * for some common types of keys.
467 * If hash_func is %NULL, g_direct_hash() is used.
468 * @key_equal_func: a function to check two keys for equality. This is
469 * used when looking up keys in the #GHashTable. The g_direct_equal(),
470 * g_int_equal(), g_int64_equal(), g_double_equal() and g_str_equal()
471 * functions are provided for the most common types of keys.
472 * If @key_equal_func is %NULL, keys are compared directly in a similar
473 * fashion to g_direct_equal(), but without the overhead of a function call.
475 * Creates a new #GHashTable with a reference count of 1.
477 * Return value: a new #GHashTable.
480 g_hash_table_new (GHashFunc hash_func,
481 GEqualFunc key_equal_func)
483 return g_hash_table_new_full (hash_func, key_equal_func, NULL, NULL);
488 * g_hash_table_new_full:
489 * @hash_func: a function to create a hash value from a key.
490 * @key_equal_func: a function to check two keys for equality.
491 * @key_destroy_func: a function to free the memory allocated for the key
492 * used when removing the entry from the #GHashTable or %NULL if you
493 * don't want to supply such a function.
494 * @value_destroy_func: a function to free the memory allocated for the
495 * value used when removing the entry from the #GHashTable or %NULL if
496 * you don't want to supply such a function.
498 * Creates a new #GHashTable like g_hash_table_new() with a reference count
499 * of 1 and allows to specify functions to free the memory allocated for the
500 * key and value that get called when removing the entry from the #GHashTable.
502 * Return value: a new #GHashTable.
505 g_hash_table_new_full (GHashFunc hash_func,
506 GEqualFunc key_equal_func,
507 GDestroyNotify key_destroy_func,
508 GDestroyNotify value_destroy_func)
510 GHashTable *hash_table;
512 hash_table = g_slice_new (GHashTable);
513 g_hash_table_set_shift (hash_table, HASH_TABLE_MIN_SHIFT);
514 hash_table->nnodes = 0;
515 hash_table->noccupied = 0;
516 hash_table->hash_func = hash_func ? hash_func : g_direct_hash;
517 hash_table->key_equal_func = key_equal_func;
518 hash_table->ref_count = 1;
519 #ifndef G_DISABLE_ASSERT
520 hash_table->version = 0;
522 hash_table->key_destroy_func = key_destroy_func;
523 hash_table->value_destroy_func = value_destroy_func;
524 hash_table->nodes = g_new0 (GHashNode, hash_table->size);
530 * g_hash_table_iter_init:
531 * @iter: an uninitialized #GHashTableIter.
532 * @hash_table: a #GHashTable.
534 * Initializes a key/value pair iterator and associates it with
535 * @hash_table. Modifying the hash table after calling this function
536 * invalidates the returned iterator.
538 * GHashTableIter iter;
539 * gpointer key, value;
541 * g_hash_table_iter_init (&iter, hash_table);
542 * while (g_hash_table_iter_next (&iter, &key, &value))
544 * /* do something with key and value */
551 g_hash_table_iter_init (GHashTableIter *iter,
552 GHashTable *hash_table)
554 RealIter *ri = (RealIter *) iter;
556 g_return_if_fail (iter != NULL);
557 g_return_if_fail (hash_table != NULL);
559 ri->hash_table = hash_table;
561 #ifndef G_DISABLE_ASSERT
562 ri->version = hash_table->version;
567 * g_hash_table_iter_next:
568 * @iter: an initialized #GHashTableIter.
569 * @key: a location to store the key, or %NULL.
570 * @value: a location to store the value, or %NULL.
572 * Advances @iter and retrieves the key and/or value that are now
573 * pointed to as a result of this advancement. If %FALSE is returned,
574 * @key and @value are not set, and the iterator becomes invalid.
576 * Return value: %FALSE if the end of the #GHashTable has been reached.
581 g_hash_table_iter_next (GHashTableIter *iter,
585 RealIter *ri = (RealIter *) iter;
589 g_return_val_if_fail (iter != NULL, FALSE);
590 #ifndef G_DISABLE_ASSERT
591 g_return_val_if_fail (ri->version == ri->hash_table->version, FALSE);
593 g_return_val_if_fail (ri->position < ri->hash_table->size, FALSE);
595 position = ri->position;
600 if (position >= ri->hash_table->size)
602 ri->position = position;
606 node = &ri->hash_table->nodes [position];
608 while (node->key_hash <= 1);
613 *value = node->value;
615 ri->position = position;
620 * g_hash_table_iter_get_hash_table:
621 * @iter: an initialized #GHashTableIter.
623 * Returns the #GHashTable associated with @iter.
625 * Return value: the #GHashTable associated with @iter.
630 g_hash_table_iter_get_hash_table (GHashTableIter *iter)
632 g_return_val_if_fail (iter != NULL, NULL);
634 return ((RealIter *) iter)->hash_table;
638 iter_remove_or_steal (RealIter *ri, gboolean notify)
640 g_return_if_fail (ri != NULL);
641 #ifndef G_DISABLE_ASSERT
642 g_return_if_fail (ri->version == ri->hash_table->version);
644 g_return_if_fail (ri->position >= 0);
645 g_return_if_fail (ri->position < ri->hash_table->size);
647 g_hash_table_remove_node (ri->hash_table, &ri->hash_table->nodes [ri->position], notify);
649 #ifndef G_DISABLE_ASSERT
651 ri->hash_table->version++;
656 * g_hash_table_iter_remove():
657 * @iter: an initialized #GHashTableIter.
659 * Removes the key/value pair currently pointed to by the iterator
660 * from its associated #GHashTable. Can only be called after
661 * g_hash_table_iter_next() returned %TRUE, and cannot be called more
662 * than once for the same key/value pair.
664 * If the #GHashTable was created using g_hash_table_new_full(), the
665 * key and value are freed using the supplied destroy functions, otherwise
666 * you have to make sure that any dynamically allocated values are freed
672 g_hash_table_iter_remove (GHashTableIter *iter)
674 iter_remove_or_steal ((RealIter *) iter, TRUE);
678 * g_hash_table_iter_steal():
679 * @iter: an initialized #GHashTableIter.
681 * Removes the key/value pair currently pointed to by the iterator
682 * from its associated #GHashTable, without calling the key and value
683 * destroy functions. Can only be called after
684 * g_hash_table_iter_next() returned %TRUE, and cannot be called more
685 * than once for the same key/value pair.
690 g_hash_table_iter_steal (GHashTableIter *iter)
692 iter_remove_or_steal ((RealIter *) iter, FALSE);
698 * @hash_table: a valid #GHashTable.
700 * Atomically increments the reference count of @hash_table by one.
701 * This function is MT-safe and may be called from any thread.
703 * Return value: the passed in #GHashTable.
708 g_hash_table_ref (GHashTable *hash_table)
710 g_return_val_if_fail (hash_table != NULL, NULL);
711 g_return_val_if_fail (hash_table->ref_count > 0, hash_table);
713 g_atomic_int_add (&hash_table->ref_count, 1);
718 * g_hash_table_unref:
719 * @hash_table: a valid #GHashTable.
721 * Atomically decrements the reference count of @hash_table by one.
722 * If the reference count drops to 0, all keys and values will be
723 * destroyed, and all memory allocated by the hash table is released.
724 * This function is MT-safe and may be called from any thread.
729 g_hash_table_unref (GHashTable *hash_table)
731 g_return_if_fail (hash_table != NULL);
732 g_return_if_fail (hash_table->ref_count > 0);
734 if (g_atomic_int_exchange_and_add (&hash_table->ref_count, -1) - 1 == 0)
736 g_hash_table_remove_all_nodes (hash_table, TRUE);
737 g_free (hash_table->nodes);
738 g_slice_free (GHashTable, hash_table);
743 * g_hash_table_destroy:
744 * @hash_table: a #GHashTable.
746 * Destroys all keys and values in the #GHashTable and decrements its
747 * reference count by 1. If keys and/or values are dynamically allocated,
748 * you should either free them first or create the #GHashTable with destroy
749 * notifiers using g_hash_table_new_full(). In the latter case the destroy
750 * functions you supplied will be called on all keys and values during the
754 g_hash_table_destroy (GHashTable *hash_table)
756 g_return_if_fail (hash_table != NULL);
757 g_return_if_fail (hash_table->ref_count > 0);
759 g_hash_table_remove_all (hash_table);
760 g_hash_table_unref (hash_table);
764 * g_hash_table_lookup:
765 * @hash_table: a #GHashTable.
766 * @key: the key to look up.
768 * Looks up a key in a #GHashTable. Note that this function cannot
769 * distinguish between a key that is not present and one which is present
770 * and has the value %NULL. If you need this distinction, use
771 * g_hash_table_lookup_extended().
773 * Return value: the associated value, or %NULL if the key is not found.
776 g_hash_table_lookup (GHashTable *hash_table,
782 g_return_val_if_fail (hash_table != NULL, NULL);
784 node_index = g_hash_table_lookup_node (hash_table, key);
785 node = &hash_table->nodes [node_index];
787 return node->key_hash ? node->value : NULL;
791 * g_hash_table_lookup_extended:
792 * @hash_table: a #GHashTable
793 * @lookup_key: the key to look up
794 * @orig_key: return location for the original key, or %NULL
795 * @value: return location for the value associated with the key, or %NULL
797 * Looks up a key in the #GHashTable, returning the original key and the
798 * associated value and a #gboolean which is %TRUE if the key was found. This
799 * is useful if you need to free the memory allocated for the original key,
800 * for example before calling g_hash_table_remove().
802 * You can actually pass %NULL for @lookup_key to test
803 * whether the %NULL key exists.
805 * Return value: %TRUE if the key was found in the #GHashTable.
808 g_hash_table_lookup_extended (GHashTable *hash_table,
809 gconstpointer lookup_key,
816 g_return_val_if_fail (hash_table != NULL, FALSE);
818 node_index = g_hash_table_lookup_node (hash_table, lookup_key);
819 node = &hash_table->nodes [node_index];
825 *orig_key = node->key;
828 *value = node->value;
834 * g_hash_table_insert_internal:
835 * @hash_table: our #GHashTable
836 * @key: the key to insert
837 * @value: the value to insert
838 * @keep_new_key: if %TRUE and this key already exists in the table
839 * then call the destroy notify function on the old key. If %FALSE
840 * then call the destroy notify function on the new key.
842 * Implements the common logic for the g_hash_table_insert() and
843 * g_hash_table_replace() functions.
845 * Do a lookup of @key. If it is found, replace it with the new
846 * @value (and perhaps the new @key). If it is not found, create a
850 g_hash_table_insert_internal (GHashTable *hash_table,
853 gboolean keep_new_key)
860 g_return_if_fail (hash_table != NULL);
861 g_return_if_fail (hash_table->ref_count > 0);
863 node_index = g_hash_table_lookup_node_for_insertion (hash_table, key, &key_hash);
864 node = &hash_table->nodes [node_index];
866 old_hash = node->key_hash;
872 if (hash_table->key_destroy_func)
873 hash_table->key_destroy_func (node->key);
878 if (hash_table->key_destroy_func)
879 hash_table->key_destroy_func (key);
882 if (hash_table->value_destroy_func)
883 hash_table->value_destroy_func (node->value);
891 node->key_hash = key_hash;
893 hash_table->nnodes++;
897 /* We replaced an empty node, and not a tombstone */
898 hash_table->noccupied++;
899 g_hash_table_maybe_resize (hash_table);
902 #ifndef G_DISABLE_ASSERT
903 hash_table->version++;
909 * g_hash_table_insert:
910 * @hash_table: a #GHashTable.
911 * @key: a key to insert.
912 * @value: the value to associate with the key.
914 * Inserts a new key and value into a #GHashTable.
916 * If the key already exists in the #GHashTable its current value is replaced
917 * with the new value. If you supplied a @value_destroy_func when creating the
918 * #GHashTable, the old value is freed using that function. If you supplied
919 * a @key_destroy_func when creating the #GHashTable, the passed key is freed
920 * using that function.
923 g_hash_table_insert (GHashTable *hash_table,
927 g_hash_table_insert_internal (hash_table, key, value, FALSE);
931 * g_hash_table_replace:
932 * @hash_table: a #GHashTable.
933 * @key: a key to insert.
934 * @value: the value to associate with the key.
936 * Inserts a new key and value into a #GHashTable similar to
937 * g_hash_table_insert(). The difference is that if the key already exists
938 * in the #GHashTable, it gets replaced by the new key. If you supplied a
939 * @value_destroy_func when creating the #GHashTable, the old value is freed
940 * using that function. If you supplied a @key_destroy_func when creating the
941 * #GHashTable, the old key is freed using that function.
944 g_hash_table_replace (GHashTable *hash_table,
948 g_hash_table_insert_internal (hash_table, key, value, TRUE);
952 * g_hash_table_remove_internal:
953 * @hash_table: our #GHashTable
954 * @key: the key to remove
955 * @notify: %TRUE if the destroy notify handlers are to be called
956 * Return value: %TRUE if a node was found and removed, else %FALSE
958 * Implements the common logic for the g_hash_table_remove() and
959 * g_hash_table_steal() functions.
961 * Do a lookup of @key and remove it if it is found, calling the
962 * destroy notify handlers only if @notify is %TRUE.
965 g_hash_table_remove_internal (GHashTable *hash_table,
972 g_return_val_if_fail (hash_table != NULL, FALSE);
974 node_index = g_hash_table_lookup_node (hash_table, key);
975 node = &hash_table->nodes [node_index];
977 /* g_hash_table_lookup_node() never returns a tombstone, so this is safe */
981 g_hash_table_remove_node (hash_table, node, notify);
982 g_hash_table_maybe_resize (hash_table);
984 #ifndef G_DISABLE_ASSERT
985 hash_table->version++;
992 * g_hash_table_remove:
993 * @hash_table: a #GHashTable.
994 * @key: the key to remove.
996 * Removes a key and its associated value from a #GHashTable.
998 * If the #GHashTable was created using g_hash_table_new_full(), the
999 * key and value are freed using the supplied destroy functions, otherwise
1000 * you have to make sure that any dynamically allocated values are freed
1003 * Return value: %TRUE if the key was found and removed from the #GHashTable.
1006 g_hash_table_remove (GHashTable *hash_table,
1009 return g_hash_table_remove_internal (hash_table, key, TRUE);
1013 * g_hash_table_steal:
1014 * @hash_table: a #GHashTable.
1015 * @key: the key to remove.
1017 * Removes a key and its associated value from a #GHashTable without
1018 * calling the key and value destroy functions.
1020 * Return value: %TRUE if the key was found and removed from the #GHashTable.
1023 g_hash_table_steal (GHashTable *hash_table,
1026 return g_hash_table_remove_internal (hash_table, key, FALSE);
1030 * g_hash_table_remove_all:
1031 * @hash_table: a #GHashTable
1033 * Removes all keys and their associated values from a #GHashTable.
1035 * If the #GHashTable was created using g_hash_table_new_full(), the keys
1036 * and values are freed using the supplied destroy functions, otherwise you
1037 * have to make sure that any dynamically allocated values are freed
1043 g_hash_table_remove_all (GHashTable *hash_table)
1045 g_return_if_fail (hash_table != NULL);
1047 #ifndef G_DISABLE_ASSERT
1048 if (hash_table->nnodes != 0)
1049 hash_table->version++;
1052 g_hash_table_remove_all_nodes (hash_table, TRUE);
1053 g_hash_table_maybe_resize (hash_table);
1057 * g_hash_table_steal_all:
1058 * @hash_table: a #GHashTable.
1060 * Removes all keys and their associated values from a #GHashTable
1061 * without calling the key and value destroy functions.
1066 g_hash_table_steal_all (GHashTable *hash_table)
1068 g_return_if_fail (hash_table != NULL);
1070 #ifndef G_DISABLE_ASSERT
1071 if (hash_table->nnodes != 0)
1072 hash_table->version++;
1075 g_hash_table_remove_all_nodes (hash_table, FALSE);
1076 g_hash_table_maybe_resize (hash_table);
1080 * g_hash_table_foreach_remove_or_steal:
1081 * @hash_table: our #GHashTable
1082 * @func: the user's callback function
1083 * @user_data: data for @func
1084 * @notify: %TRUE if the destroy notify handlers are to be called
1086 * Implements the common logic for g_hash_table_foreach_remove() and
1087 * g_hash_table_foreach_steal().
1089 * Iterates over every node in the table, calling @func with the key
1090 * and value of the node (and @user_data). If @func returns %TRUE the
1091 * node is removed from the table.
1093 * If @notify is true then the destroy notify handlers will be called
1094 * for each removed node.
1097 g_hash_table_foreach_remove_or_steal (GHashTable *hash_table,
1105 for (i = 0; i < hash_table->size; i++)
1107 GHashNode *node = &hash_table->nodes [i];
1109 if (node->key_hash > 1 && (* func) (node->key, node->value, user_data))
1111 g_hash_table_remove_node (hash_table, node, notify);
1116 g_hash_table_maybe_resize (hash_table);
1118 #ifndef G_DISABLE_ASSERT
1120 hash_table->version++;
1127 * g_hash_table_foreach_remove:
1128 * @hash_table: a #GHashTable.
1129 * @func: the function to call for each key/value pair.
1130 * @user_data: user data to pass to the function.
1132 * Calls the given function for each key/value pair in the #GHashTable.
1133 * If the function returns %TRUE, then the key/value pair is removed from the
1134 * #GHashTable. If you supplied key or value destroy functions when creating
1135 * the #GHashTable, they are used to free the memory allocated for the removed
1138 * See #GHashTableIter for an alternative way to loop over the
1139 * key/value pairs in the hash table.
1141 * Return value: the number of key/value pairs removed.
1144 g_hash_table_foreach_remove (GHashTable *hash_table,
1148 g_return_val_if_fail (hash_table != NULL, 0);
1149 g_return_val_if_fail (func != NULL, 0);
1151 return g_hash_table_foreach_remove_or_steal (hash_table, func, user_data, TRUE);
1155 * g_hash_table_foreach_steal:
1156 * @hash_table: a #GHashTable.
1157 * @func: the function to call for each key/value pair.
1158 * @user_data: user data to pass to the function.
1160 * Calls the given function for each key/value pair in the #GHashTable.
1161 * If the function returns %TRUE, then the key/value pair is removed from the
1162 * #GHashTable, but no key or value destroy functions are called.
1164 * See #GHashTableIter for an alternative way to loop over the
1165 * key/value pairs in the hash table.
1167 * Return value: the number of key/value pairs removed.
1170 g_hash_table_foreach_steal (GHashTable *hash_table,
1174 g_return_val_if_fail (hash_table != NULL, 0);
1175 g_return_val_if_fail (func != NULL, 0);
1177 return g_hash_table_foreach_remove_or_steal (hash_table, func, user_data, FALSE);
1181 * g_hash_table_foreach:
1182 * @hash_table: a #GHashTable.
1183 * @func: the function to call for each key/value pair.
1184 * @user_data: user data to pass to the function.
1186 * Calls the given function for each of the key/value pairs in the
1187 * #GHashTable. The function is passed the key and value of each
1188 * pair, and the given @user_data parameter. The hash table may not
1189 * be modified while iterating over it (you can't add/remove
1190 * items). To remove all items matching a predicate, use
1191 * g_hash_table_foreach_remove().
1193 * See g_hash_table_find() for performance caveats for linear
1194 * order searches in contrast to g_hash_table_lookup().
1197 g_hash_table_foreach (GHashTable *hash_table,
1203 g_return_if_fail (hash_table != NULL);
1204 g_return_if_fail (func != NULL);
1206 for (i = 0; i < hash_table->size; i++)
1208 GHashNode *node = &hash_table->nodes [i];
1210 if (node->key_hash > 1)
1211 (* func) (node->key, node->value, user_data);
1216 * g_hash_table_find:
1217 * @hash_table: a #GHashTable.
1218 * @predicate: function to test the key/value pairs for a certain property.
1219 * @user_data: user data to pass to the function.
1221 * Calls the given function for key/value pairs in the #GHashTable until
1222 * @predicate returns %TRUE. The function is passed the key and value of
1223 * each pair, and the given @user_data parameter. The hash table may not
1224 * be modified while iterating over it (you can't add/remove items).
1226 * Note, that hash tables are really only optimized for forward lookups,
1227 * i.e. g_hash_table_lookup().
1228 * So code that frequently issues g_hash_table_find() or
1229 * g_hash_table_foreach() (e.g. in the order of once per every entry in a
1230 * hash table) should probably be reworked to use additional or different
1231 * data structures for reverse lookups (keep in mind that an O(n) find/foreach
1232 * operation issued for all n values in a hash table ends up needing O(n*n)
1235 * Return value: The value of the first key/value pair is returned, for which
1236 * func evaluates to %TRUE. If no pair with the requested property is found,
1237 * %NULL is returned.
1242 g_hash_table_find (GHashTable *hash_table,
1248 g_return_val_if_fail (hash_table != NULL, NULL);
1249 g_return_val_if_fail (predicate != NULL, NULL);
1251 for (i = 0; i < hash_table->size; i++)
1253 GHashNode *node = &hash_table->nodes [i];
1255 if (node->key_hash > 1 && predicate (node->key, node->value, user_data))
1263 * g_hash_table_size:
1264 * @hash_table: a #GHashTable.
1266 * Returns the number of elements contained in the #GHashTable.
1268 * Return value: the number of key/value pairs in the #GHashTable.
1271 g_hash_table_size (GHashTable *hash_table)
1273 g_return_val_if_fail (hash_table != NULL, 0);
1275 return hash_table->nnodes;
1279 * g_hash_table_get_keys:
1280 * @hash_table: a #GHashTable
1282 * Retrieves every key inside @hash_table. The returned data is valid
1283 * until @hash_table is modified.
1285 * Return value: a #GList containing all the keys inside the hash
1286 * table. The content of the list is owned by the hash table and
1287 * should not be modified or freed. Use g_list_free() when done
1293 g_hash_table_get_keys (GHashTable *hash_table)
1298 g_return_val_if_fail (hash_table != NULL, NULL);
1301 for (i = 0; i < hash_table->size; i++)
1303 GHashNode *node = &hash_table->nodes [i];
1305 if (node->key_hash > 1)
1306 retval = g_list_prepend (retval, node->key);
1313 * g_hash_table_get_values:
1314 * @hash_table: a #GHashTable
1316 * Retrieves every value inside @hash_table. The returned data is
1317 * valid until @hash_table is modified.
1319 * Return value: a #GList containing all the values inside the hash
1320 * table. The content of the list is owned by the hash table and
1321 * should not be modified or freed. Use g_list_free() when done
1327 g_hash_table_get_values (GHashTable *hash_table)
1332 g_return_val_if_fail (hash_table != NULL, NULL);
1335 for (i = 0; i < hash_table->size; i++)
1337 GHashNode *node = &hash_table->nodes [i];
1339 if (node->key_hash > 1)
1340 retval = g_list_prepend (retval, node->value);
1346 #define __G_HASH_C__
1347 #include "galiasdef.c"