Sequential list data type implemented by a binary tree.

[gnulib.git] / lib / gl_avltree_list.c

diff --git a/lib/gl_avltree_list.c b/lib/gl_avltree_list.c
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+/* Sequential list data type implemented by a binary tree.
+   Copyright (C) 2006 Free Software Foundation, Inc.
+   Written by Bruno Haible <bruno@clisp.org>, 2006.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software Foundation,
+   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+/* Specification.  */
+#include "gl_avltree_list.h"
+
+#include <stdlib.h>
+
+#include "xalloc.h"
+
+/* -------------------------- gl_list_t Data Type -------------------------- */
+
+/* Generic AVL tree code.  */
+#include "gl_anyavltree_list1.h"
+#include "gl_anyavltree_list2.h"
+
+/* Generic binary tree code.  */
+#include "gl_anytree_list1.h"
+#include "gl_anytree_list2.h"
+
+/* For debugging.  */
+static unsigned int
+check_invariants (gl_list_node_t node, gl_list_node_t parent)
+{
+  unsigned int left_height =
+    (node->left != NULL ? check_invariants (node->left, node) : 0);
+  unsigned int right_height =
+    (node->right != NULL ? check_invariants (node->right, node) : 0);
+  int balance = (int)right_height - (int)left_height;
+
+  if (!(node->parent == parent))
+    abort ();
+  if (!(node->branch_size
+       == (node->left != NULL ? node->left->branch_size : 0)
+          + 1 + (node->right != NULL ? node->right->branch_size : 0)))
+    abort ();
+  if (!(balance >= -1 && balance <= 1))
+    abort ();
+  if (!(node->balance == balance))
+    abort ();
+
+  return 1 + (left_height > right_height ? left_height : right_height);
+}
+void
+gl_avltree_list_check_invariants (gl_list_t list)
+{
+  if (list->root != NULL)
+    check_invariants (list->root, NULL);
+}
+
+const struct gl_list_implementation gl_avltree_list_implementation =
+  {
+    gl_tree_create_empty,
+    gl_tree_create,
+    gl_tree_size,
+    gl_tree_node_value,
+    gl_tree_next_node,
+    gl_tree_previous_node,
+    gl_tree_get_at,
+    gl_tree_set_at,
+    gl_tree_search,
+    gl_tree_indexof,
+    gl_tree_add_first,
+    gl_tree_add_last,
+    gl_tree_add_before,
+    gl_tree_add_after,
+    gl_tree_add_at,
+    gl_tree_remove_node,
+    gl_tree_remove_at,
+    gl_tree_remove,
+    gl_tree_list_free,
+    gl_tree_iterator,
+    gl_tree_iterator_from_to,
+    gl_tree_iterator_next,
+    gl_tree_iterator_free,
+    gl_tree_sortedlist_search,
+    gl_tree_sortedlist_indexof,
+    gl_tree_sortedlist_add,
+    gl_tree_sortedlist_remove
+  };