2 * Copyright (C) 2000 Red Hat, Inc., Jonathan Blandford <jrb@redhat.com>
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library 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 * Library General Public License for more details.
14 * You should have received a copy of the GNU Library 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.
20 #include "gtkrbtree.h"
23 static void _gtk_rbnode_validate_allocator (GAllocator *allocator);
24 static GtkRBNode *_gtk_rbnode_new (GtkRBTree *tree,
26 static void _gtk_rbnode_free (GtkRBNode *node);
27 static void _gtk_rbnode_rotate_left (GtkRBTree *tree,
29 static void _gtk_rbnode_rotate_left (GtkRBTree *tree,
31 static void _gtk_rbtree_insert_fixup (GtkRBTree *tree,
33 static void _gtk_rbtree_remove_node_fixup (GtkRBTree *tree,
35 static gint _count_nodes (GtkRBTree *tree,
41 struct _GAllocator /* from gmem.c */
49 GtkRBNode *free_nodes; /* implementation specific */
53 G_LOCK_DEFINE_STATIC (current_allocator);
54 static GAllocator *current_allocator = NULL;
56 /* HOLDS: current_allocator_lock */
58 _gtk_rbnode_validate_allocator (GAllocator *allocator)
60 g_return_if_fail (allocator != NULL);
61 g_return_if_fail (allocator->is_unused == TRUE);
63 if (allocator->type != G_ALLOCATOR_NODE)
65 allocator->type = G_ALLOCATOR_NODE;
66 if (allocator->mem_chunk)
68 g_mem_chunk_destroy (allocator->mem_chunk);
69 allocator->mem_chunk = NULL;
73 if (!allocator->mem_chunk)
75 allocator->mem_chunk = g_mem_chunk_new (allocator->name,
77 sizeof (GtkRBNode) * allocator->n_preallocs,
79 allocator->free_nodes = NULL;
82 allocator->is_unused = FALSE;
86 _gtk_rbnode_new (GtkRBTree *tree,
91 G_LOCK (current_allocator);
92 if (!current_allocator)
94 GAllocator *allocator = g_allocator_new ("GTK+ default GtkRBNode allocator",
96 _gtk_rbnode_validate_allocator (allocator);
97 allocator->last = NULL;
98 current_allocator = allocator;
100 if (!current_allocator->free_nodes)
101 node = g_chunk_new (GtkRBNode, current_allocator->mem_chunk);
104 node = current_allocator->free_nodes;
105 current_allocator->free_nodes = node->left;
107 G_UNLOCK (current_allocator);
109 node->left = tree->nil;
110 node->right = tree->nil;
111 node->parent = tree->nil;
112 node->flags = GTK_RBNODE_RED;
114 node->children = NULL;
115 node->offset = height;
120 _gtk_rbnode_free (GtkRBNode *node)
122 G_LOCK (current_allocator);
123 node->left = current_allocator->free_nodes;
124 current_allocator->free_nodes = node;
125 G_UNLOCK (current_allocator);
129 _gtk_rbnode_rotate_left (GtkRBTree *tree,
132 gint node_height, right_height;
133 GtkRBNode *right = node->right;
135 g_return_if_fail (node != tree->nil);
137 node_height = node->offset -
138 (node->left?node->left->offset:0) -
139 (node->right?node->right->offset:0) -
140 (node->children?node->children->root->offset:0);
141 right_height = right->offset -
142 (right->left?right->left->offset:0) -
143 (right->right?right->right->offset:0) -
144 (right->children?right->children->root->offset:0);
146 node->right = right->left;
147 if (right->left != tree->nil)
148 right->left->parent = node;
150 if (right != tree->nil)
151 right->parent = node->parent;
152 if (node->parent != tree->nil)
154 if (node == node->parent->left)
155 node->parent->left = right;
157 node->parent->right = right;
163 if (node != tree->nil)
164 node->parent = right;
166 node->count = 1 + (node->left?node->left->count:0) +
167 (node->right?node->right->count:0);
168 right->count = 1 + (right->left?right->left->count:0) +
169 (right->right?right->right->count:0);
170 node->offset = node_height +
171 (node->left?node->left->offset:0) +
172 (node->right?node->right->offset:0) +
173 (node->children?node->children->root->offset:0);
174 right->offset = right_height +
175 (right->left?right->left->offset:0) +
176 (right->right?right->right->offset:0) +
177 (right->children?right->children->root->offset:0);
181 _gtk_rbnode_rotate_right (GtkRBTree *tree,
184 gint node_height, left_height;
185 GtkRBNode *left = node->left;
187 g_return_if_fail (node != tree->nil);
189 node_height = node->offset -
190 (node->left?node->left->offset:0) -
191 (node->right?node->right->offset:0) -
192 (node->children?node->children->root->offset:0);
193 left_height = left->offset -
194 (left->left?left->left->offset:0) -
195 (left->right?left->right->offset:0) -
196 (left->children?left->children->root->offset:0);
198 node->left = left->right;
199 if (left->right != tree->nil)
200 left->right->parent = node;
202 if (left != tree->nil)
203 left->parent = node->parent;
204 if (node->parent != tree->nil)
206 if (node == node->parent->right)
207 node->parent->right = left;
209 node->parent->left = left;
216 /* link node and left */
218 if (node != tree->nil)
221 node->count = 1 + (node->left?node->left->count:0) +
222 (node->right?node->right->count:0);
223 left->count = 1 + (left->left?left->left->count:0) +
224 (left->right?left->right->count:0);
225 node->offset = node_height +
226 (node->left?node->left->offset:0) +
227 (node->right?node->right->offset:0) +
228 (node->children?node->children->root->offset:0);
229 left->offset = left_height +
230 (left->left?left->left->offset:0) +
231 (left->right?left->right->offset:0) +
232 (left->children?left->children->root->offset:0);
236 _gtk_rbtree_insert_fixup (GtkRBTree *tree,
240 /* check Red-Black properties */
241 while (node != tree->root && GTK_RBNODE_GET_COLOR (node->parent) == GTK_RBNODE_RED)
243 /* we have a violation */
244 if (node->parent == node->parent->parent->left)
246 GtkRBNode *y = node->parent->parent->right;
247 if (GTK_RBNODE_GET_COLOR (y) == GTK_RBNODE_RED)
249 /* uncle is GTK_RBNODE_RED */
250 GTK_RBNODE_SET_COLOR (node->parent, GTK_RBNODE_BLACK);
251 GTK_RBNODE_SET_COLOR (y, GTK_RBNODE_BLACK);
252 GTK_RBNODE_SET_COLOR (node->parent->parent, GTK_RBNODE_RED);
253 node = node->parent->parent;
257 /* uncle is GTK_RBNODE_BLACK */
258 if (node == node->parent->right)
260 /* make node a left child */
262 _gtk_rbnode_rotate_left (tree, node);
265 /* recolor and rotate */
266 GTK_RBNODE_SET_COLOR (node->parent, GTK_RBNODE_BLACK);
267 GTK_RBNODE_SET_COLOR (node->parent->parent, GTK_RBNODE_RED);
268 _gtk_rbnode_rotate_right(tree, node->parent->parent);
273 /* mirror image of above code */
274 GtkRBNode *y = node->parent->parent->left;
275 if (GTK_RBNODE_GET_COLOR (y) == GTK_RBNODE_RED)
277 /* uncle is GTK_RBNODE_RED */
278 GTK_RBNODE_SET_COLOR (node->parent, GTK_RBNODE_BLACK);
279 GTK_RBNODE_SET_COLOR (y, GTK_RBNODE_BLACK);
280 GTK_RBNODE_SET_COLOR (node->parent->parent, GTK_RBNODE_RED);
281 node = node->parent->parent;
285 /* uncle is GTK_RBNODE_BLACK */
286 if (node == node->parent->left)
289 _gtk_rbnode_rotate_right (tree, node);
291 GTK_RBNODE_SET_COLOR (node->parent, GTK_RBNODE_BLACK);
292 GTK_RBNODE_SET_COLOR (node->parent->parent, GTK_RBNODE_RED);
293 _gtk_rbnode_rotate_left (tree, node->parent->parent);
297 GTK_RBNODE_SET_COLOR (tree->root, GTK_RBNODE_BLACK);
301 _gtk_rbtree_remove_node_fixup (GtkRBTree *tree,
304 while (node != tree->root && GTK_RBNODE_GET_COLOR (node) == GTK_RBNODE_BLACK)
306 if (node == node->parent->left)
308 GtkRBNode *w = node->parent->right;
309 if (GTK_RBNODE_GET_COLOR (w) == GTK_RBNODE_RED)
311 GTK_RBNODE_SET_COLOR (w, GTK_RBNODE_BLACK);
312 GTK_RBNODE_SET_COLOR (node->parent, GTK_RBNODE_RED);
313 _gtk_rbnode_rotate_left (tree, node->parent);
314 w = node->parent->right;
316 if (GTK_RBNODE_GET_COLOR (w->left) == GTK_RBNODE_BLACK && GTK_RBNODE_GET_COLOR (w->right) == GTK_RBNODE_BLACK)
318 GTK_RBNODE_SET_COLOR (w, GTK_RBNODE_RED);
323 if (GTK_RBNODE_GET_COLOR (w->right) == GTK_RBNODE_BLACK)
325 GTK_RBNODE_SET_COLOR (w->left, GTK_RBNODE_BLACK);
326 GTK_RBNODE_SET_COLOR (w, GTK_RBNODE_RED);
327 _gtk_rbnode_rotate_right (tree, w);
328 w = node->parent->right;
330 GTK_RBNODE_SET_COLOR (w, GTK_RBNODE_GET_COLOR (node->parent));
331 GTK_RBNODE_SET_COLOR (node->parent, GTK_RBNODE_BLACK);
332 GTK_RBNODE_SET_COLOR (w->right, GTK_RBNODE_BLACK);
333 _gtk_rbnode_rotate_left (tree, node->parent);
339 GtkRBNode *w = node->parent->left;
340 if (GTK_RBNODE_GET_COLOR (w) == GTK_RBNODE_RED)
342 GTK_RBNODE_SET_COLOR (w, GTK_RBNODE_BLACK);
343 GTK_RBNODE_SET_COLOR (node->parent, GTK_RBNODE_RED);
344 _gtk_rbnode_rotate_right (tree, node->parent);
345 w = node->parent->left;
347 if (GTK_RBNODE_GET_COLOR (w->right) == GTK_RBNODE_BLACK && GTK_RBNODE_GET_COLOR (w->left) == GTK_RBNODE_BLACK)
349 GTK_RBNODE_SET_COLOR (w, GTK_RBNODE_RED);
354 if (GTK_RBNODE_GET_COLOR (w->left) == GTK_RBNODE_BLACK)
356 GTK_RBNODE_SET_COLOR (w->right, GTK_RBNODE_BLACK);
357 GTK_RBNODE_SET_COLOR (w, GTK_RBNODE_RED);
358 _gtk_rbnode_rotate_left (tree, w);
359 w = node->parent->left;
361 GTK_RBNODE_SET_COLOR (w, GTK_RBNODE_GET_COLOR (node->parent));
362 GTK_RBNODE_SET_COLOR (node->parent, GTK_RBNODE_BLACK);
363 GTK_RBNODE_SET_COLOR (w->left, GTK_RBNODE_BLACK);
364 _gtk_rbnode_rotate_right (tree, node->parent);
369 GTK_RBNODE_SET_COLOR (node, GTK_RBNODE_BLACK);
372 /* Public functions */
374 _gtk_rbnode_push_allocator (GAllocator *allocator)
376 G_LOCK (current_allocator);
377 _gtk_rbnode_validate_allocator ( allocator );
378 allocator->last = current_allocator;
379 current_allocator = allocator;
380 G_UNLOCK (current_allocator);
384 _gtk_rbnode_pop_allocator (void)
386 G_LOCK (current_allocator);
387 if (current_allocator)
389 GAllocator *allocator;
391 allocator = current_allocator;
392 current_allocator = allocator->last;
393 allocator->last = NULL;
394 allocator->is_unused = TRUE;
396 G_UNLOCK (current_allocator);
400 _gtk_rbtree_new (void)
404 retval = (GtkRBTree *) g_new (GtkRBTree, 1);
405 retval->parent_tree = NULL;
406 retval->parent_node = NULL;
408 retval->nil = g_new0 (GtkRBNode, 1);
409 retval->nil->left = NULL;
410 retval->nil->right = NULL;
411 retval->nil->parent = NULL;
412 retval->nil->flags = GTK_RBNODE_BLACK;
413 retval->nil->count = 0;
414 retval->nil->offset = 0;
416 retval->root = retval->nil;
421 _gtk_rbtree_free_helper (GtkRBTree *tree,
426 _gtk_rbtree_free (node->children);
428 _gtk_rbnode_free (node);
432 _gtk_rbtree_free (GtkRBTree *tree)
434 _gtk_rbtree_traverse (tree,
437 _gtk_rbtree_free_helper,
440 if (tree->parent_node &&
441 tree->parent_node->children == tree)
442 tree->parent_node->children = NULL;
443 _gtk_rbnode_free (tree->nil);
448 _gtk_rbtree_remove (GtkRBTree *tree)
453 gint height = tree->root->offset;
454 tmp_tree = tree->parent_tree;
455 tmp_node = tree->parent_node;
457 while (tmp_tree && tmp_node && tmp_node != tmp_tree->nil)
459 tmp_node->offset -= height;
460 tmp_node = tmp_node->parent;
461 if (tmp_node == tmp_tree->nil)
463 tmp_node = tmp_tree->parent_node;
464 tmp_tree = tmp_tree->parent_tree;
467 _gtk_rbtree_free (tree);
472 _gtk_rbtree_insert_after (GtkRBTree *tree,
477 gboolean right = TRUE;
481 if (current != NULL && current->right != tree->nil)
483 current = current->right;
484 while (current->left != tree->nil)
485 current = current->left;
490 node = _gtk_rbnode_new (tree, height);
491 node->parent = (current?current:tree->nil);
493 /* insert node in tree */
497 current->right = node;
499 current->left = node;
500 tmp_node = node->parent;
506 tmp_node = tree->parent_node;
507 tmp_tree = tree->parent_tree;
510 while (tmp_tree && tmp_node && tmp_node != tmp_tree->nil)
512 /* We only want to propagate the count if we are in the tree we
514 if (tmp_tree == tree)
516 tmp_node->offset += height;
517 tmp_node = tmp_node->parent;
518 if (tmp_node == tmp_tree->nil)
520 tmp_node = tmp_tree->parent_node;
521 tmp_tree = tmp_tree->parent_tree;
524 _gtk_rbtree_insert_fixup (tree, node);
526 if (gtk_debug_flags & GTK_DEBUG_TREE)
527 _gtk_rbtree_test (tree);
533 _gtk_rbtree_insert_before (GtkRBTree *tree,
538 gboolean left = TRUE;
542 if (current != NULL && current->left != tree->nil)
544 current = current->left;
545 while (current->right != tree->nil)
546 current = current->right;
551 node = _gtk_rbnode_new (tree, height);
552 node->parent = (current?current:tree->nil);
554 /* insert node in tree */
558 current->left = node;
560 current->right = node;
561 tmp_node = node->parent;
567 tmp_node = tree->parent_node;
568 tmp_tree = tree->parent_tree;
571 while (tmp_tree && tmp_node && tmp_node != tmp_tree->nil)
573 /* We only want to propagate the count if we are in the tree we
575 if (tmp_tree == tree)
577 tmp_node->offset += height;
578 tmp_node = tmp_node->parent;
579 if (tmp_node == tmp_tree->nil)
581 tmp_node = tmp_tree->parent_node;
582 tmp_tree = tmp_tree->parent_tree;
585 _gtk_rbtree_insert_fixup (tree, node);
587 if (gtk_debug_flags & GTK_DEBUG_TREE)
588 _gtk_rbtree_test (tree);
594 _gtk_rbtree_find_count (GtkRBTree *tree,
600 while (node != tree->nil && (node->left->count + 1 != count))
602 if (node->left->count >= count)
606 count -= (node->left->count + 1);
610 if (node == tree->nil)
616 _gtk_rbtree_node_set_height (GtkRBTree *tree,
620 gint diff = height - GTK_RBNODE_GET_HEIGHT (node);
621 GtkRBNode *tmp_node = node;
622 GtkRBTree *tmp_tree = tree;
627 while (tmp_tree && tmp_node && tmp_node != tmp_tree->nil)
629 tmp_node->offset += diff;
630 tmp_node = tmp_node->parent;
631 if (tmp_node == tmp_tree->nil)
633 tmp_node = tmp_tree->parent_node;
634 tmp_tree = tmp_tree->parent_tree;
640 _gtk_rbtree_node_find_offset (GtkRBTree *tree,
644 gint retval = node->left->offset;
646 while (tree && node && node != tree->nil)
650 if (node->right == last)
651 retval += node->left->offset + GTK_RBNODE_GET_HEIGHT (node);
652 if (node == tree->nil)
654 node = tree->parent_node;
655 tree = tree->parent_tree;
657 retval += node->left->offset;
664 _gtk_rbtree_find_offset (GtkRBTree *tree,
666 GtkRBTree **new_tree,
667 GtkRBNode **new_node)
678 tmp_node = tree->root;
679 while (tmp_node != tree->nil &&
680 (tmp_node->left->offset > height ||
681 (tmp_node->offset - tmp_node->right->offset) < height))
683 if (tmp_node->left->offset > height)
684 tmp_node = tmp_node->left;
687 height -= (tmp_node->offset - tmp_node->right->offset);
688 tmp_node = tmp_node->right;
691 if (tmp_node == tree->nil)
697 if (tmp_node->children)
699 if ((tmp_node->offset -
700 tmp_node->right->offset -
701 tmp_node->children->root->offset) > height)
704 *new_node = tmp_node;
705 return (height - tmp_node->left->offset);
707 return _gtk_rbtree_find_offset (tmp_node->children,
708 height - tmp_node->left->offset -
710 tmp_node->left->offset -
711 tmp_node->right->offset -
712 tmp_node->children->root->offset),
717 *new_node = tmp_node;
718 return (height - tmp_node->left->offset);
723 _gtk_rbtree_remove_node (GtkRBTree *tree,
728 g_return_if_fail (tree != NULL);
729 g_return_if_fail (node != NULL);
730 /* make sure we're deleting a node that's actually in the tree */
731 for (x = node; x->parent != tree->nil; x = x->parent)
733 g_return_if_fail (x == tree->root);
735 if (node->left == tree->nil || node->right == tree->nil)
743 while (y->left != tree->nil)
746 for (x = y; x != tree->nil; x = x->parent)
748 y->count = node->count;
749 /* x is y's only child */
750 if (y->left != tree->nil)
755 /* remove y from the parent chain */
756 x->parent = y->parent;
757 if (y->parent != tree->nil)
758 if (y == y->parent->left)
761 y->parent->right = x;
766 node->children = y->children;
768 if (GTK_RBNODE_GET_COLOR (y) == GTK_RBNODE_BLACK)
769 _gtk_rbtree_remove_node_fixup (tree, x);
771 G_LOCK (current_allocator);
772 y->left = current_allocator->free_nodes;
773 current_allocator->free_nodes = y;
774 G_UNLOCK (current_allocator);
776 if (gtk_debug_flags & GTK_DEBUG_TREE)
777 _gtk_rbtree_test (tree);
781 _gtk_rbtree_next (GtkRBTree *tree,
784 g_return_val_if_fail (tree != NULL, NULL);
785 g_return_val_if_fail (node != NULL, NULL);
787 /* Case 1: the node's below us. */
788 if (node->right != tree->nil)
791 while (node->left != tree->nil)
796 /* Case 2: it's an ancestor */
797 while (node->parent != tree->nil)
799 if (node->parent->right == node)
802 return (node->parent);
805 /* Case 3: There is no next node */
810 _gtk_rbtree_prev (GtkRBTree *tree,
813 g_return_val_if_fail (tree != NULL, NULL);
814 g_return_val_if_fail (node != NULL, NULL);
816 /* Case 1: the node's below us. */
817 if (node->left != tree->nil)
820 while (node->right != tree->nil)
825 /* Case 2: it's an ancestor */
826 while (node->parent != tree->nil)
828 if (node->parent->left == node)
831 return (node->parent);
834 /* Case 3: There is no next node */
839 _gtk_rbtree_next_full (GtkRBTree *tree,
841 GtkRBTree **new_tree,
842 GtkRBNode **new_node)
844 g_return_if_fail (tree != NULL);
845 g_return_if_fail (node != NULL);
846 g_return_if_fail (new_tree != NULL);
847 g_return_if_fail (new_node != NULL);
851 *new_tree = node->children;
852 *new_node = (*new_tree)->root;
853 while ((*new_node)->left != (*new_tree)->nil)
854 *new_node = (*new_node)->left;
859 *new_node = _gtk_rbtree_next (tree, node);
861 while ((*new_node == NULL) &&
864 *new_node = (*new_tree)->parent_node;
865 *new_tree = (*new_tree)->parent_tree;
867 *new_node = _gtk_rbtree_next (*new_tree, *new_node);
872 _gtk_rbtree_prev_full (GtkRBTree *tree,
874 GtkRBTree **new_tree,
875 GtkRBNode **new_node)
877 g_return_if_fail (tree != NULL);
878 g_return_if_fail (node != NULL);
879 g_return_if_fail (new_tree != NULL);
880 g_return_if_fail (new_node != NULL);
883 *new_node = _gtk_rbtree_prev (tree, node);
885 if (*new_node == NULL)
887 *new_node = (*new_tree)->parent_node;
888 *new_tree = (*new_tree)->parent_tree;
892 while ((*new_node)->children)
894 *new_tree = (*new_node)->children;
895 *new_node = (*new_tree)->root;
896 while ((*new_node)->right != (*new_tree)->nil)
897 *new_node = (*new_node)->right;
903 _gtk_rbtree_traverse_pre_order (GtkRBTree *tree,
905 GtkRBTreeTraverseFunc func,
908 if (node == tree->nil)
911 (* func) (tree, node, data);
912 _gtk_rbtree_traverse_pre_order (tree, node->left, func, data);
913 _gtk_rbtree_traverse_pre_order (tree, node->right, func, data);
917 _gtk_rbtree_traverse_post_order (GtkRBTree *tree,
919 GtkRBTreeTraverseFunc func,
922 if (node == tree->nil)
925 _gtk_rbtree_traverse_post_order (tree, node->left, func, data);
926 _gtk_rbtree_traverse_post_order (tree, node->right, func, data);
927 (* func) (tree, node, data);
931 _gtk_rbtree_traverse (GtkRBTree *tree,
934 GtkRBTreeTraverseFunc func,
937 g_return_if_fail (tree != NULL);
938 g_return_if_fail (node != NULL);
939 g_return_if_fail (func != NULL);
940 g_return_if_fail (order <= G_LEVEL_ORDER);
945 _gtk_rbtree_traverse_pre_order (tree, node, func, data);
948 _gtk_rbtree_traverse_post_order (tree, node, func, data);
953 g_warning ("unsupported traversal order.");
959 _count_nodes (GtkRBTree *tree,
963 if (node == tree->nil)
966 res = (_count_nodes (tree, node->left) +
967 _count_nodes (tree, node->right) + 1);
969 if (res != node->count)
970 g_print ("Tree failed\n");
975 _gtk_rbtree_test (GtkRBTree *tree)
977 if ((_count_nodes (tree, tree->root->left) +
978 _count_nodes (tree, tree->root->right) + 1) == tree->root->count)
979 g_print ("Tree passed\n");
981 g_print ("Tree failed\n");
986 _gtk_rbtree_test_height_helper (GtkRBTree *tree,
990 if (node == tree->nil)
994 (node->left?node->left->offset:0) -
995 (node->right?node->right->offset:0) -
996 (node->children?node->children->root->offset:0) != height)
997 g_error ("tree failed\n");
999 _gtk_rbtree_test_height_helper (tree, node->left, height);
1000 _gtk_rbtree_test_height_helper (tree, node->right, height);
1002 _gtk_rbtree_test_height_helper (node->children, node->children->root, height);
1007 _gtk_rbtree_test_height (GtkRBTree *tree,
1010 _gtk_rbtree_test_height_helper (tree, tree->root, height);