1 /* GLIB - Library of useful routines for C programming
2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
4 * GNode: N-way tree implementation.
5 * Copyright (C) 1998 Tim Janik
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
24 * Modified by the GLib Team and others 1997-2000. See the AUTHORS
25 * file for a list of people on the GLib Team. See the ChangeLog
26 * files for a list of changes. These files are distributed with
27 * GLib at ftp://ftp.gtk.org/pub/gtk/.
41 * @short_description: trees of data with any number of branches
43 * The #GNode struct and its associated functions provide a N-ary tree
44 * data structure, where nodes in the tree can contain arbitrary data.
46 * To create a new tree use g_node_new().
48 * To insert a node into a tree use g_node_insert(),
49 * g_node_insert_before(), g_node_append() and g_node_prepend().
51 * To create a new node and insert it into a tree use
52 * g_node_insert_data(), g_node_insert_data_before(),
53 * g_node_append_data() and g_node_prepend_data().
55 * To reverse the children of a node use g_node_reverse_children().
57 * To find a node use g_node_get_root(), g_node_find(),
58 * g_node_find_child(), g_node_child_index(), g_node_child_position(),
59 * g_node_first_child(), g_node_last_child(), g_node_nth_child(),
60 * g_node_first_sibling(), g_node_prev_sibling(), g_node_next_sibling()
61 * or g_node_last_sibling().
63 * To get information about a node or tree use G_NODE_IS_LEAF(),
64 * G_NODE_IS_ROOT(), g_node_depth(), g_node_n_nodes(),
65 * g_node_n_children(), g_node_is_ancestor() or g_node_max_height().
67 * To traverse a tree, calling a function for each node visited in the
68 * traversal, use g_node_traverse() or g_node_children_foreach().
70 * To remove a node or subtree from a tree use g_node_unlink() or
76 * @data: contains the actual data of the node.
77 * @next: points to the node's next sibling (a sibling is another
78 * #GNode with the same parent).
79 * @prev: points to the node's previous sibling.
80 * @parent: points to the parent of the #GNode, or is %NULL if the
81 * #GNode is the root of the tree.
82 * @children: points to the first child of the #GNode. The other
83 * children are accessed by using the @next pointer of each
86 * The #GNode struct represents one node in a
87 * <link linkend="glib-N-ary-Trees">N-ary Tree</link>. fields
91 * g_node_push_allocator:
92 * @dummy: the #GAllocator to use when allocating #GNode elements.
94 * Sets the allocator to use to allocate #GNode elements. Use
95 * g_node_pop_allocator() to restore the previous allocator.
97 * Note that this function is not available if GLib has been compiled
98 * with <option>--disable-mem-pools</option>
100 * Deprecated:2.10: It does nothing, since #GNode has been converted to
101 * the <link linkend="glib-Memory-Slices">slice
104 void g_node_push_allocator (gpointer dummy) { /* present for binary compat only */ }
107 * g_node_pop_allocator:
109 * Restores the previous #GAllocator, used when allocating #GNode
112 * Note that this function is not available if GLib has been compiled
113 * with <option>--disable-mem-pools</option>
115 * Deprecated:2.10: It does nothing, since #GNode has been converted to
116 * the <link linkend="glib-Memory-Slices">slice
119 void g_node_pop_allocator (void) { /* present for binary compat only */ }
121 #define g_node_alloc0() g_slice_new0 (GNode)
122 #define g_node_free(node) g_slice_free (GNode, node)
124 /* --- functions --- */
127 * @data: the data of the new node
129 * Creates a new #GNode containing the given data.
130 * Used to create the first node in a tree.
132 * Returns: a new #GNode
135 g_node_new (gpointer data)
137 GNode *node = g_node_alloc0 ();
143 g_nodes_free (GNode *node)
147 GNode *next = node->next;
149 g_nodes_free (node->children);
157 * @root: the root of the tree/subtree to destroy
159 * Removes @root and its children from the tree, freeing any memory
163 g_node_destroy (GNode *root)
165 g_return_if_fail (root != NULL);
167 if (!G_NODE_IS_ROOT (root))
168 g_node_unlink (root);
175 * @node: the #GNode to unlink, which becomes the root of a new tree
177 * Unlinks a #GNode from a tree, resulting in two separate trees.
180 g_node_unlink (GNode *node)
182 g_return_if_fail (node != NULL);
185 node->prev->next = node->next;
186 else if (node->parent)
187 node->parent->children = node->next;
191 node->next->prev = node->prev;
200 * @copy_func: the function which is called to copy the data inside each node,
201 * or %NULL to use the original data.
202 * @data: data to pass to @copy_func
204 * Recursively copies a #GNode and its data.
206 * Return value: a new #GNode containing copies of the data in @node.
211 g_node_copy_deep (GNode *node,
215 GNode *new_node = NULL;
217 if (copy_func == NULL)
218 return g_node_copy (node);
222 GNode *child, *new_child;
224 new_node = g_node_new (copy_func (node->data, data));
226 for (child = g_node_last_child (node); child; child = child->prev)
228 new_child = g_node_copy_deep (child, copy_func, data);
229 g_node_prepend (new_node, new_child);
240 * Recursively copies a #GNode (but does not deep-copy the data inside the
241 * nodes, see g_node_copy_deep() if you need that).
243 * Returns: a new #GNode containing the same data pointers
246 g_node_copy (GNode *node)
248 GNode *new_node = NULL;
254 new_node = g_node_new (node->data);
256 for (child = g_node_last_child (node); child; child = child->prev)
257 g_node_prepend (new_node, g_node_copy (child));
265 * @parent: the #GNode to place @node under
266 * @position: the position to place @node at, with respect to its siblings
267 * If position is -1, @node is inserted as the last child of @parent
268 * @node: the #GNode to insert
270 * Inserts a #GNode beneath the parent at the given position.
272 * Returns: the inserted #GNode
275 g_node_insert (GNode *parent,
279 g_return_val_if_fail (parent != NULL, node);
280 g_return_val_if_fail (node != NULL, node);
281 g_return_val_if_fail (G_NODE_IS_ROOT (node), node);
284 return g_node_insert_before (parent,
285 g_node_nth_child (parent, position),
287 else if (position == 0)
288 return g_node_prepend (parent, node);
289 else /* if (position < 0) */
290 return g_node_append (parent, node);
294 * g_node_insert_before:
295 * @parent: the #GNode to place @node under
296 * @sibling: the sibling #GNode to place @node before.
297 * If sibling is %NULL, the node is inserted as the last child of @parent.
298 * @node: the #GNode to insert
300 * Inserts a #GNode beneath the parent before the given sibling.
302 * Returns: the inserted #GNode
305 g_node_insert_before (GNode *parent,
309 g_return_val_if_fail (parent != NULL, node);
310 g_return_val_if_fail (node != NULL, node);
311 g_return_val_if_fail (G_NODE_IS_ROOT (node), node);
313 g_return_val_if_fail (sibling->parent == parent, node);
315 node->parent = parent;
321 node->prev = sibling->prev;
322 node->prev->next = node;
323 node->next = sibling;
324 sibling->prev = node;
328 node->parent->children = node;
329 node->next = sibling;
330 sibling->prev = node;
335 if (parent->children)
337 sibling = parent->children;
338 while (sibling->next)
339 sibling = sibling->next;
340 node->prev = sibling;
341 sibling->next = node;
344 node->parent->children = node;
351 * g_node_insert_after:
352 * @parent: the #GNode to place @node under
353 * @sibling: the sibling #GNode to place @node after.
354 * If sibling is %NULL, the node is inserted as the first child of @parent.
355 * @node: the #GNode to insert
357 * Inserts a #GNode beneath the parent after the given sibling.
359 * Returns: the inserted #GNode
362 g_node_insert_after (GNode *parent,
366 g_return_val_if_fail (parent != NULL, node);
367 g_return_val_if_fail (node != NULL, node);
368 g_return_val_if_fail (G_NODE_IS_ROOT (node), node);
370 g_return_val_if_fail (sibling->parent == parent, node);
372 node->parent = parent;
378 sibling->next->prev = node;
380 node->next = sibling->next;
381 node->prev = sibling;
382 sibling->next = node;
386 if (parent->children)
388 node->next = parent->children;
389 parent->children->prev = node;
391 parent->children = node;
399 * @parent: the #GNode to place the new #GNode under
400 * @node: the #GNode to insert
402 * Inserts a #GNode as the first child of the given parent.
404 * Returns: the inserted #GNode
407 g_node_prepend (GNode *parent,
410 g_return_val_if_fail (parent != NULL, node);
412 return g_node_insert_before (parent, parent->children, node);
419 * Gets the root of a tree.
421 * Returns: the root of the tree
424 g_node_get_root (GNode *node)
426 g_return_val_if_fail (node != NULL, NULL);
435 * g_node_is_ancestor:
437 * @descendant: a #GNode
439 * Returns %TRUE if @node is an ancestor of @descendant.
440 * This is true if node is the parent of @descendant,
441 * or if node is the grandparent of @descendant etc.
443 * Returns: %TRUE if @node is an ancestor of @descendant
446 g_node_is_ancestor (GNode *node,
449 g_return_val_if_fail (node != NULL, FALSE);
450 g_return_val_if_fail (descendant != NULL, FALSE);
454 if (descendant->parent == node)
457 descendant = descendant->parent;
467 * Gets the depth of a #GNode.
469 * If @node is %NULL the depth is 0. The root node has a depth of 1.
470 * For the children of the root node the depth is 2. And so on.
472 * Returns: the depth of the #GNode
475 g_node_depth (GNode *node)
489 * g_node_reverse_children:
492 * Reverses the order of the children of a #GNode.
493 * (It doesn't change the order of the grandchildren.)
496 g_node_reverse_children (GNode *node)
501 g_return_if_fail (node != NULL);
503 child = node->children;
509 last->next = last->prev;
512 node->children = last;
519 * Gets the maximum height of all branches beneath a #GNode.
520 * This is the maximum distance from the #GNode to all leaf nodes.
522 * If @root is %NULL, 0 is returned. If @root has no children,
523 * 1 is returned. If @root has children, 2 is returned. And so on.
525 * Returns: the maximum height of the tree beneath @root
528 g_node_max_height (GNode *root)
531 guint max_height = 0;
536 child = root->children;
541 tmp_height = g_node_max_height (child);
542 if (tmp_height > max_height)
543 max_height = tmp_height;
547 return max_height + 1;
551 g_node_traverse_pre_order (GNode *node,
552 GTraverseFlags flags,
553 GNodeTraverseFunc func,
560 if ((flags & G_TRAVERSE_NON_LEAFS) &&
564 child = node->children;
570 child = current->next;
571 if (g_node_traverse_pre_order (current, flags, func, data))
575 else if ((flags & G_TRAVERSE_LEAFS) &&
583 g_node_depth_traverse_pre_order (GNode *node,
584 GTraverseFlags flags,
586 GNodeTraverseFunc func,
593 if ((flags & G_TRAVERSE_NON_LEAFS) &&
601 child = node->children;
607 child = current->next;
608 if (g_node_depth_traverse_pre_order (current, flags, depth, func, data))
612 else if ((flags & G_TRAVERSE_LEAFS) &&
620 g_node_traverse_post_order (GNode *node,
621 GTraverseFlags flags,
622 GNodeTraverseFunc func,
629 child = node->children;
635 child = current->next;
636 if (g_node_traverse_post_order (current, flags, func, data))
640 if ((flags & G_TRAVERSE_NON_LEAFS) &&
645 else if ((flags & G_TRAVERSE_LEAFS) &&
653 g_node_depth_traverse_post_order (GNode *node,
654 GTraverseFlags flags,
656 GNodeTraverseFunc func,
666 child = node->children;
672 child = current->next;
673 if (g_node_depth_traverse_post_order (current, flags, depth, func, data))
678 if ((flags & G_TRAVERSE_NON_LEAFS) &&
683 else if ((flags & G_TRAVERSE_LEAFS) &&
691 g_node_traverse_in_order (GNode *node,
692 GTraverseFlags flags,
693 GNodeTraverseFunc func,
701 child = node->children;
703 child = current->next;
705 if (g_node_traverse_in_order (current, flags, func, data))
708 if ((flags & G_TRAVERSE_NON_LEAFS) &&
715 child = current->next;
716 if (g_node_traverse_in_order (current, flags, func, data))
720 else if ((flags & G_TRAVERSE_LEAFS) &&
728 g_node_depth_traverse_in_order (GNode *node,
729 GTraverseFlags flags,
731 GNodeTraverseFunc func,
742 child = node->children;
744 child = current->next;
746 if (g_node_depth_traverse_in_order (current, flags, depth, func, data))
749 if ((flags & G_TRAVERSE_NON_LEAFS) &&
756 child = current->next;
757 if (g_node_depth_traverse_in_order (current, flags, depth, func, data))
761 else if ((flags & G_TRAVERSE_NON_LEAFS) &&
765 else if ((flags & G_TRAVERSE_LEAFS) &&
773 g_node_traverse_level (GNode *node,
774 GTraverseFlags flags,
776 GNodeTraverseFunc func,
778 gboolean *more_levels)
785 return (flags & G_TRAVERSE_NON_LEAFS) && func (node, data);
789 return (flags & G_TRAVERSE_LEAFS) && func (node, data);
794 node = node->children;
798 if (g_node_traverse_level (node, flags, level - 1, func, data, more_levels))
809 g_node_depth_traverse_level (GNode *node,
810 GTraverseFlags flags,
812 GNodeTraverseFunc func,
816 gboolean more_levels;
819 while (level != depth)
822 if (g_node_traverse_level (node, flags, level, func, data, &more_levels))
833 * @root: the root #GNode of the tree to traverse
834 * @order: the order in which nodes are visited - %G_IN_ORDER,
835 * %G_PRE_ORDER, %G_POST_ORDER, or %G_LEVEL_ORDER.
836 * @flags: which types of children are to be visited, one of
837 * %G_TRAVERSE_ALL, %G_TRAVERSE_LEAVES and %G_TRAVERSE_NON_LEAVES
838 * @max_depth: the maximum depth of the traversal. Nodes below this
839 * depth will not be visited. If max_depth is -1 all nodes in
840 * the tree are visited. If depth is 1, only the root is visited.
841 * If depth is 2, the root and its children are visited. And so on.
842 * @func: the function to call for each visited #GNode
843 * @data: user data to pass to the function
845 * Traverses a tree starting at the given root #GNode.
846 * It calls the given function for each node visited.
847 * The traversal can be halted at any point by returning %TRUE from @func.
851 * @G_TRAVERSE_LEAVES: only leaf nodes should be visited. This name has
852 * been introduced in 2.6, for older version use
854 * @G_TRAVERSE_NON_LEAVES: only non-leaf nodes should be visited. This
855 * name has been introduced in 2.6, for older
856 * version use %G_TRAVERSE_NON_LEAFS.
857 * @G_TRAVERSE_ALL: all nodes should be visited.
858 * @G_TRAVERSE_MASK: a mask of all traverse flags.
859 * @G_TRAVERSE_LEAFS: identical to %G_TRAVERSE_LEAVES.
860 * @G_TRAVERSE_NON_LEAFS: identical to %G_TRAVERSE_NON_LEAVES.
862 * Specifies which nodes are visited during several of the tree
863 * functions, including g_node_traverse() and g_node_find().
868 * @data: user data passed to g_node_traverse().
869 * @Returns: %TRUE to stop the traversal.
871 * Specifies the type of function passed to g_node_traverse(). The
872 * function is called with each of the nodes visited, together with the
873 * user data passed to g_node_traverse(). If the function returns
874 * %TRUE, then the traversal is stopped.
877 g_node_traverse (GNode *root,
879 GTraverseFlags flags,
881 GNodeTraverseFunc func,
884 g_return_if_fail (root != NULL);
885 g_return_if_fail (func != NULL);
886 g_return_if_fail (order <= G_LEVEL_ORDER);
887 g_return_if_fail (flags <= G_TRAVERSE_MASK);
888 g_return_if_fail (depth == -1 || depth > 0);
894 g_node_traverse_pre_order (root, flags, func, data);
896 g_node_depth_traverse_pre_order (root, flags, depth, func, data);
900 g_node_traverse_post_order (root, flags, func, data);
902 g_node_depth_traverse_post_order (root, flags, depth, func, data);
906 g_node_traverse_in_order (root, flags, func, data);
908 g_node_depth_traverse_in_order (root, flags, depth, func, data);
911 g_node_depth_traverse_level (root, flags, depth, func, data);
917 g_node_find_func (GNode *node,
922 if (*d != node->data)
932 * @root: the root #GNode of the tree to search
933 * @order: the order in which nodes are visited - %G_IN_ORDER,
934 * %G_PRE_ORDER, %G_POST_ORDER, or %G_LEVEL_ORDER
935 * @flags: which types of children are to be searched, one of
936 * %G_TRAVERSE_ALL, %G_TRAVERSE_LEAVES and %G_TRAVERSE_NON_LEAVES
937 * @data: the data to find
939 * Finds a #GNode in a tree.
941 * Returns: the found #GNode, or %NULL if the data is not found
944 g_node_find (GNode *root,
946 GTraverseFlags flags,
951 g_return_val_if_fail (root != NULL, NULL);
952 g_return_val_if_fail (order <= G_LEVEL_ORDER, NULL);
953 g_return_val_if_fail (flags <= G_TRAVERSE_MASK, NULL);
958 g_node_traverse (root, order, flags, -1, g_node_find_func, d);
964 g_node_count_func (GNode *node,
965 GTraverseFlags flags,
972 if (flags & G_TRAVERSE_NON_LEAFS)
975 child = node->children;
978 g_node_count_func (child, flags, n);
982 else if (flags & G_TRAVERSE_LEAFS)
989 * @flags: which types of children are to be counted, one of
990 * %G_TRAVERSE_ALL, %G_TRAVERSE_LEAVES and %G_TRAVERSE_NON_LEAVES
992 * Gets the number of nodes in a tree.
994 * Returns: the number of nodes in the tree
997 g_node_n_nodes (GNode *root,
998 GTraverseFlags flags)
1002 g_return_val_if_fail (root != NULL, 0);
1003 g_return_val_if_fail (flags <= G_TRAVERSE_MASK, 0);
1005 g_node_count_func (root, flags, &n);
1011 * g_node_last_child:
1012 * @node: a #GNode (must not be %NULL)
1014 * Gets the last child of a #GNode.
1016 * Returns: the last child of @node, or %NULL if @node has no children
1019 g_node_last_child (GNode *node)
1021 g_return_val_if_fail (node != NULL, NULL);
1023 node = node->children;
1034 * @n: the index of the desired child
1036 * Gets a child of a #GNode, using the given index.
1037 * The first child is at index 0. If the index is
1038 * too big, %NULL is returned.
1040 * Returns: the child of @node at index @n
1043 g_node_nth_child (GNode *node,
1046 g_return_val_if_fail (node != NULL, NULL);
1048 node = node->children;
1050 while ((n-- > 0) && node)
1057 * g_node_n_children:
1060 * Gets the number of children of a #GNode.
1062 * Returns: the number of children of @node
1065 g_node_n_children (GNode *node)
1069 g_return_val_if_fail (node != NULL, 0);
1071 node = node->children;
1082 * g_node_find_child:
1084 * @flags: which types of children are to be searched, one of
1085 * %G_TRAVERSE_ALL, %G_TRAVERSE_LEAVES and %G_TRAVERSE_NON_LEAVES
1086 * @data: the data to find
1088 * Finds the first child of a #GNode with the given data.
1090 * Returns: the found child #GNode, or %NULL if the data is not found
1093 g_node_find_child (GNode *node,
1094 GTraverseFlags flags,
1097 g_return_val_if_fail (node != NULL, NULL);
1098 g_return_val_if_fail (flags <= G_TRAVERSE_MASK, NULL);
1100 node = node->children;
1103 if (node->data == data)
1105 if (G_NODE_IS_LEAF (node))
1107 if (flags & G_TRAVERSE_LEAFS)
1112 if (flags & G_TRAVERSE_NON_LEAFS)
1123 * g_node_child_position:
1125 * @child: a child of @node
1127 * Gets the position of a #GNode with respect to its siblings.
1128 * @child must be a child of @node. The first child is numbered 0,
1129 * the second 1, and so on.
1131 * Returns: the position of @child with respect to its siblings
1134 g_node_child_position (GNode *node,
1139 g_return_val_if_fail (node != NULL, -1);
1140 g_return_val_if_fail (child != NULL, -1);
1141 g_return_val_if_fail (child->parent == node, -1);
1143 node = node->children;
1156 * g_node_child_index:
1158 * @data: the data to find
1160 * Gets the position of the first child of a #GNode
1161 * which contains the given data.
1163 * Returns: the index of the child of @node which contains
1164 * @data, or -1 if the data is not found
1167 g_node_child_index (GNode *node,
1172 g_return_val_if_fail (node != NULL, -1);
1174 node = node->children;
1177 if (node->data == data)
1187 * g_node_first_sibling:
1190 * Gets the first sibling of a #GNode.
1191 * This could possibly be the node itself.
1193 * Returns: the first sibling of @node
1196 g_node_first_sibling (GNode *node)
1198 g_return_val_if_fail (node != NULL, NULL);
1201 return node->parent->children;
1210 * g_node_last_sibling:
1213 * Gets the last sibling of a #GNode.
1214 * This could possibly be the node itself.
1216 * Returns: the last sibling of @node
1219 g_node_last_sibling (GNode *node)
1221 g_return_val_if_fail (node != NULL, NULL);
1230 * g_node_children_foreach:
1232 * @flags: which types of children are to be visited, one of
1233 * %G_TRAVERSE_ALL, %G_TRAVERSE_LEAVES and %G_TRAVERSE_NON_LEAVES
1234 * @func: the function to call for each visited node
1235 * @data: user data to pass to the function
1237 * Calls a function for each of the children of a #GNode.
1238 * Note that it doesn't descend beneath the child nodes.
1243 * @data: user data passed to g_node_children_foreach().
1245 * Specifies the type of function passed to g_node_children_foreach().
1246 * The function is called with each child node, together with the user
1247 * data passed to g_node_children_foreach().
1250 g_node_children_foreach (GNode *node,
1251 GTraverseFlags flags,
1252 GNodeForeachFunc func,
1255 g_return_if_fail (node != NULL);
1256 g_return_if_fail (flags <= G_TRAVERSE_MASK);
1257 g_return_if_fail (func != NULL);
1259 node = node->children;
1265 node = current->next;
1266 if (G_NODE_IS_LEAF (current))
1268 if (flags & G_TRAVERSE_LEAFS)
1269 func (current, data);
1273 if (flags & G_TRAVERSE_NON_LEAFS)
1274 func (current, data);