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/.
38 typedef struct _GTreeNode GTreeNode;
43 GCompareDataFunc key_compare;
44 GDestroyNotify key_destroy_func;
45 GDestroyNotify value_destroy_func;
46 gpointer key_compare_data;
51 gint balance; /* height (left) - height (right) */
52 GTreeNode *left; /* left subtree */
53 GTreeNode *right; /* right subtree */
54 gpointer key; /* key for this node */
55 gpointer value; /* value stored at this node */
59 static GTreeNode* g_tree_node_new (gpointer key,
61 static void g_tree_node_destroy (GTreeNode *node,
62 GDestroyNotify key_destroy_func,
63 GDestroyNotify value_destroy_func);
64 static GTreeNode* g_tree_node_insert (GTree *tree,
70 static GTreeNode* g_tree_node_remove (GTree *tree,
74 static GTreeNode* g_tree_node_balance (GTreeNode *node);
75 static GTreeNode* g_tree_node_remove_leftmost (GTreeNode *node,
76 GTreeNode **leftmost);
77 static GTreeNode* g_tree_node_restore_left_balance (GTreeNode *node,
79 static GTreeNode* g_tree_node_restore_right_balance (GTreeNode *node,
81 static GTreeNode* g_tree_node_lookup (GTreeNode *node,
82 GCompareDataFunc compare,
85 static gint g_tree_node_count (GTreeNode *node);
86 static gint g_tree_node_pre_order (GTreeNode *node,
87 GTraverseFunc traverse_func,
89 static gint g_tree_node_in_order (GTreeNode *node,
90 GTraverseFunc traverse_func,
92 static gint g_tree_node_post_order (GTreeNode *node,
93 GTraverseFunc traverse_func,
95 static gpointer g_tree_node_search (GTreeNode *node,
96 GCompareFunc search_func,
98 static gint g_tree_node_height (GTreeNode *node);
99 static GTreeNode* g_tree_node_rotate_left (GTreeNode *node);
100 static GTreeNode* g_tree_node_rotate_right (GTreeNode *node);
101 static void g_tree_node_check (GTreeNode *node);
104 G_LOCK_DEFINE_STATIC (g_tree_global);
105 static GMemChunk *node_mem_chunk = NULL;
106 static GTreeNode *node_free_list = NULL;
110 g_tree_node_new (gpointer key,
115 G_LOCK (g_tree_global);
118 node = node_free_list;
119 node_free_list = node->right;
124 node_mem_chunk = g_mem_chunk_new ("GLib GTreeNode mem chunk",
129 node = g_chunk_new (GTreeNode, node_mem_chunk);
131 G_UNLOCK (g_tree_global);
143 g_tree_node_destroy (GTreeNode *node,
144 GDestroyNotify key_destroy_func,
145 GDestroyNotify value_destroy_func)
149 g_tree_node_destroy (node->right,
150 key_destroy_func, value_destroy_func);
151 g_tree_node_destroy (node->left,
152 key_destroy_func, value_destroy_func);
154 if (key_destroy_func)
155 key_destroy_func (node->key);
156 if (value_destroy_func)
157 value_destroy_func (node->value);
159 #ifdef ENABLE_GC_FRIENDLY
163 #endif /* ENABLE_GC_FRIENDLY */
165 G_LOCK (g_tree_global);
166 node->right = node_free_list;
167 node_free_list = node;
168 G_UNLOCK (g_tree_global);
174 * @key_compare_func: the function used to order the nodes in the #GTree.
175 * It should return values similar to the standard
176 * <function>strcmp()</function> function -
177 * 0 if the two arguments are equal, a negative value if the first argument
178 * comes before the second, or a positive value if the first argument comes
181 * Creates a new #GTree.
183 * Return value: a new #GTree.
186 g_tree_new (GCompareFunc key_compare_func)
188 g_return_val_if_fail (key_compare_func != NULL, NULL);
190 return g_tree_new_full ((GCompareDataFunc) key_compare_func, NULL,
195 * g_tree_new_with_data:
196 * @key_compare_func: qsort()-style comparison function.
197 * @key_compare_data: data to pass to comparison function.
199 * Creates a new #GTree with a comparison function that accepts user data.
200 * See g_tree_new() for more details.
202 * Return value: a new #GTree.
205 g_tree_new_with_data (GCompareDataFunc key_compare_func,
206 gpointer key_compare_data)
208 g_return_val_if_fail (key_compare_func != NULL, NULL);
210 return g_tree_new_full (key_compare_func, key_compare_data,
216 * @key_compare_func: qsort()-style comparison function.
217 * @key_compare_data: data to pass to comparison function.
218 * @key_destroy_func: a function to free the memory allocated for the key
219 * used when removing the entry from the #GTree or #NULL if you don't
220 * want to supply such a function.
221 * @value_destroy_func: a function to free the memory allocated for the
222 * value used when removing the entry from the #GTree or #NULL if you
223 * don't want to supply such a function.
225 * Creates a new #GTree like g_tree_new() and allows to specify functions
226 * to free the memory allocated for the key and value that get called when
227 * removing the entry from the #GTree.
229 * Return value: a new #GTree.
232 g_tree_new_full (GCompareDataFunc key_compare_func,
233 gpointer key_compare_data,
234 GDestroyNotify key_destroy_func,
235 GDestroyNotify value_destroy_func)
239 g_return_val_if_fail (key_compare_func != NULL, NULL);
241 tree = g_new (GTree, 1);
243 tree->key_compare = key_compare_func;
244 tree->key_destroy_func = key_destroy_func;
245 tree->value_destroy_func = value_destroy_func;
246 tree->key_compare_data = key_compare_data;
255 * Destroys the #GTree. If keys and/or values are dynamically allocated, you
256 * should either free them first or create the #GTree using g_tree_new_full().
257 * In the latter case the destroy functions you supplied will be called on
258 * all keys and values before destroying the #GTree.
261 g_tree_destroy (GTree *tree)
263 g_return_if_fail (tree != NULL);
265 g_tree_node_destroy (tree->root,
266 tree->key_destroy_func,
267 tree->value_destroy_func);
275 * @key: the key to insert.
276 * @value: the value corresponding to the key.
278 * Inserts a key/value pair into a #GTree. If the given key already exists
279 * in the #GTree its corresponding value is set to the new value. If you
280 * supplied a value_destroy_func when creating the #GTree, the old value is
281 * freed using that function. If you supplied a @key_destroy_func when
282 * creating the #GTree, the passed key is freed using that function.
284 * The tree is automatically 'balanced' as new key/value pairs are added,
285 * so that the distance from the root to every leaf is as small as possible.
288 g_tree_insert (GTree *tree,
294 g_return_if_fail (tree != NULL);
297 tree->root = g_tree_node_insert (tree,
306 * @key: the key to insert.
307 * @value: the value corresponding to the key.
309 * Inserts a new key and value into a #GTree similar to g_tree_insert().
310 * The difference is that if the key already exists in the #GTree, it gets
311 * replaced by the new key. If you supplied a @value_destroy_func when
312 * creating the #GTree, the old value is freed using that function. If you
313 * supplied a @key_destroy_func when creating the #GTree, the old key is
314 * freed using that function.
316 * The tree is automatically 'balanced' as new key/value pairs are added,
317 * so that the distance from the root to every leaf is as small as possible.
320 g_tree_replace (GTree *tree,
326 g_return_if_fail (tree != NULL);
329 tree->root = g_tree_node_insert (tree,
338 * @key: the key to remove.
340 * Removes a key/value pair from a #GTree.
342 * If the #GTree was created using g_tree_new_full(), the key and value
343 * are freed using the supplied @destroy_functions, otherwise you have to
344 * make sure that any dynamically allocated values are freed yourself.
347 g_tree_remove (GTree *tree,
350 g_return_if_fail (tree != NULL);
352 tree->root = g_tree_node_remove (tree, tree->root, key, TRUE);
358 * @key: the key to remove.
360 * Removes a key and its associated value from a #GTree without calling
361 * the key and value destroy functions.
364 g_tree_steal (GTree *tree,
367 g_return_if_fail (tree != NULL);
369 tree->root = g_tree_node_remove (tree, tree->root, key, FALSE);
375 * @key: the key to look up.
377 * Gets the value corresponding to the given key. Since a #GTree is
378 * automatically balanced as key/value pairs are added, key lookup is very
381 * Return value: the value corresponding to the key.
384 g_tree_lookup (GTree *tree,
389 g_return_val_if_fail (tree != NULL, NULL);
391 node = g_tree_node_lookup (tree->root,
392 tree->key_compare, tree->key_compare_data, key);
394 return node ? node->value : NULL;
398 * g_tree_lookup_extended:
400 * @lookup_key: the key to look up.
401 * @orig_key: returns the original key.
402 * @value: returns the value associated with the key.
404 * Looks up a key in the #GTree, returning the original key and the
405 * associated value and a #gboolean which is %TRUE if the key was found. This
406 * is useful if you need to free the memory allocated for the original key,
407 * for example before calling g_tree_remove().
409 * Return value: %TRUE if the key was found in the #GTree.
412 g_tree_lookup_extended (GTree *tree,
413 gconstpointer lookup_key,
419 g_return_val_if_fail (tree != NULL, FALSE);
421 node = g_tree_node_lookup (tree->root,
422 tree->key_compare, tree->key_compare_data, lookup_key);
427 *orig_key = node->key;
429 *value = node->value;
439 * @func: the function to call for each node visited. If this function
440 * returns TRUE, the traversal is stopped.
441 * @user_data: user data to pass to the function.
443 * Calls the given function for each of the key/value pairs in the #GTree.
444 * The function is passed the key and value of each pair, and the given
445 * @data parameter. The tree is traversed in sorted order.
447 * The tree may not be modified while iterating over it (you can't
448 * add/remove items). To remove all items matching a predicate, you need
449 * to add each item to a list in your #GTraverseFunc as you walk over
450 * the tree, then walk the list and remove each item.
453 g_tree_foreach (GTree *tree,
457 g_return_if_fail (tree != NULL);
462 g_tree_node_in_order (tree->root, func, user_data);
468 * @traverse_func: the function to call for each node visited. If this
469 * function returns TRUE, the traversal is stopped.
470 * @traverse_type: the order in which nodes are visited, one of %G_IN_ORDER,
471 * %G_PRE_ORDER and %G_POST_ORDER.
472 * @user_data: user data to pass to the function.
474 * Calls the given function for each node in the GTree. This function is
475 * deprecated, since the order of a balanced tree is somewhat arbitrary.
476 * If you just want to visit all nodes in sorted order, use g_tree_foreach()
477 * instead. If you really need to visit nodes in a different order, consider
478 * using an <link linkend="glib-N-ary-Trees">N-ary Tree</link>.
481 g_tree_traverse (GTree *tree,
482 GTraverseFunc traverse_func,
483 GTraverseType traverse_type,
486 g_return_if_fail (tree != NULL);
491 switch (traverse_type)
494 g_tree_node_pre_order (tree->root, traverse_func, user_data);
498 g_tree_node_in_order (tree->root, traverse_func, user_data);
502 g_tree_node_post_order (tree->root, traverse_func, user_data);
506 g_warning ("g_tree_traverse(): traverse type G_LEVEL_ORDER isn't implemented.");
514 * @search_func: the comparison function used to search the #GTree.
515 * @user_data: the data passed as the second argument to the @search_func
518 * Searches a #GTree using an alternative form of the comparison function.
520 * This function is not as useful as it sounds.
521 * It allows you to use a different function for performing the lookup of
522 * a key. However, since the tree is ordered according to the @key_compare_func
523 * function passed to g_tree_new(), the function you pass to g_tree_search()
524 * must return exactly the same value as would be returned by the comparison
525 * function, for each pair of tree nodes, or the search will not work.
527 * To search for a specific value, you can use g_tree_foreach() or
530 * Return value: the value corresponding to the found key, or %NULL if the key
534 g_tree_search (GTree *tree,
535 GCompareFunc search_func,
536 gconstpointer user_data)
538 g_return_val_if_fail (tree != NULL, NULL);
541 return g_tree_node_search (tree->root, search_func, user_data);
550 * Gets the height of a #GTree.
552 * If the #GTree contains no nodes, the height is 0.
553 * If the #GTree contains only one root node the height is 1.
554 * If the root node has children the height is 2, etc.
556 * Return value: the height of the #GTree.
559 g_tree_height (GTree *tree)
561 g_return_val_if_fail (tree != NULL, 0);
564 return g_tree_node_height (tree->root);
573 * Gets the number of nodes in a #GTree.
575 * Return value: the number of nodes in the #GTree.
578 g_tree_nnodes (GTree *tree)
580 g_return_val_if_fail (tree != NULL, 0);
583 return g_tree_node_count (tree->root);
589 g_tree_node_insert (GTree *tree,
602 return g_tree_node_new (key, value);
605 cmp = tree->key_compare (key, node->key, tree->key_compare_data);
610 if (tree->value_destroy_func)
611 tree->value_destroy_func (node->value);
617 if (tree->key_destroy_func)
618 tree->key_destroy_func (node->key);
624 /* free the passed key */
625 if (tree->key_destroy_func)
626 tree->key_destroy_func (key);
636 old_balance = node->left->balance;
637 node->left = g_tree_node_insert (tree,
642 if ((old_balance != node->left->balance) && node->left->balance)
648 node->left = g_tree_node_new (key, value);
656 old_balance = node->right->balance;
657 node->right = g_tree_node_insert (tree,
662 if ((old_balance != node->right->balance) && node->right->balance)
668 node->right = g_tree_node_new (key, value);
675 if ((node->balance < -1) || (node->balance > 1))
676 node = g_tree_node_balance (node);
683 g_tree_node_remove (GTree *tree,
695 cmp = tree->key_compare (key, node->key, tree->key_compare_data);
708 old_balance = node->right->balance;
709 node->right = g_tree_node_remove_leftmost (node->right, &new_root);
710 new_root->left = node->left;
711 new_root->right = node->right;
712 new_root->balance = node->balance;
713 node = g_tree_node_restore_right_balance (new_root, old_balance);
718 if (tree->key_destroy_func)
719 tree->key_destroy_func (garbage->key);
720 if (tree->value_destroy_func)
721 tree->value_destroy_func (garbage->value);
724 #ifdef ENABLE_GC_FRIENDLY
725 garbage->left = NULL;
727 garbage->value = NULL;
728 #endif /* ENABLE_GC_FRIENDLY */
730 G_LOCK (g_tree_global);
731 garbage->right = node_free_list;
732 node_free_list = garbage;
733 G_UNLOCK (g_tree_global);
739 old_balance = node->left->balance;
740 node->left = g_tree_node_remove (tree, node->left, key, notify);
741 node = g_tree_node_restore_left_balance (node, old_balance);
748 old_balance = node->right->balance;
749 node->right = g_tree_node_remove (tree, node->right, key, notify);
750 node = g_tree_node_restore_right_balance (node, old_balance);
758 g_tree_node_balance (GTreeNode *node)
760 if (node->balance < -1)
762 if (node->left->balance > 0)
763 node->left = g_tree_node_rotate_left (node->left);
764 node = g_tree_node_rotate_right (node);
766 else if (node->balance > 1)
768 if (node->right->balance < 0)
769 node->right = g_tree_node_rotate_right (node->right);
770 node = g_tree_node_rotate_left (node);
777 g_tree_node_remove_leftmost (GTreeNode *node,
778 GTreeNode **leftmost)
788 old_balance = node->left->balance;
789 node->left = g_tree_node_remove_leftmost (node->left, leftmost);
790 return g_tree_node_restore_left_balance (node, old_balance);
794 g_tree_node_restore_left_balance (GTreeNode *node,
799 else if ((node->left->balance != old_balance) &&
800 (node->left->balance == 0))
803 if (node->balance > 1)
804 return g_tree_node_balance (node);
809 g_tree_node_restore_right_balance (GTreeNode *node,
814 else if ((node->right->balance != old_balance) &&
815 (node->right->balance == 0))
818 if (node->balance < -1)
819 return g_tree_node_balance (node);
824 g_tree_node_lookup (GTreeNode *node,
825 GCompareDataFunc compare,
826 gpointer compare_data,
834 cmp = (* compare) (key, node->key, compare_data);
841 return g_tree_node_lookup (node->left, compare, compare_data, key);
846 return g_tree_node_lookup (node->right, compare, compare_data, key);
853 g_tree_node_count (GTreeNode *node)
859 count += g_tree_node_count (node->left);
861 count += g_tree_node_count (node->right);
867 g_tree_node_pre_order (GTreeNode *node,
868 GTraverseFunc traverse_func,
871 if ((*traverse_func) (node->key, node->value, data))
875 if (g_tree_node_pre_order (node->left, traverse_func, data))
880 if (g_tree_node_pre_order (node->right, traverse_func, data))
888 g_tree_node_in_order (GTreeNode *node,
889 GTraverseFunc traverse_func,
894 if (g_tree_node_in_order (node->left, traverse_func, data))
897 if ((*traverse_func) (node->key, node->value, data))
901 if (g_tree_node_in_order (node->right, traverse_func, data))
909 g_tree_node_post_order (GTreeNode *node,
910 GTraverseFunc traverse_func,
915 if (g_tree_node_post_order (node->left, traverse_func, data))
920 if (g_tree_node_post_order (node->right, traverse_func, data))
923 if ((*traverse_func) (node->key, node->value, data))
930 g_tree_node_search (GTreeNode *node,
931 GCompareFunc search_func,
940 dir = (* search_func) (node->key, data);
954 g_tree_node_height (GTreeNode *node)
965 left_height = g_tree_node_height (node->left);
968 right_height = g_tree_node_height (node->right);
970 return MAX (left_height, right_height) + 1;
977 g_tree_node_rotate_left (GTreeNode *node)
985 node->right = right->left;
988 a_bal = node->balance;
989 b_bal = right->balance;
994 right->balance = b_bal - 1;
996 right->balance = a_bal + b_bal - 2;
997 node->balance = a_bal - 1;
1002 right->balance = a_bal - 2;
1004 right->balance = b_bal - 1;
1005 node->balance = a_bal - b_bal - 1;
1012 g_tree_node_rotate_right (GTreeNode *node)
1020 node->left = left->right;
1023 a_bal = node->balance;
1024 b_bal = left->balance;
1029 left->balance = b_bal + 1;
1031 left->balance = a_bal + 2;
1032 node->balance = a_bal - b_bal + 1;
1037 left->balance = b_bal + 1;
1039 left->balance = a_bal + b_bal + 2;
1040 node->balance = a_bal + 1;
1047 g_tree_node_check (GTreeNode *node)
1059 left_height = g_tree_node_height (node->left);
1061 right_height = g_tree_node_height (node->right);
1063 balance = right_height - left_height;
1064 if (balance != node->balance)
1065 g_log (G_LOG_DOMAIN, G_LOG_LEVEL_INFO,
1066 "g_tree_node_check: failed: %d ( %d )\n",
1067 balance, node->balance);
1070 g_tree_node_check (node->left);
1072 g_tree_node_check (node->right);