Index: generic/include/adt/btree.h
===================================================================
--- generic/include/adt/btree.h	(revision 45fb65c09103dff87bfb6916993a019f9309b363)
+++ generic/include/adt/btree.h	(revision 45fb65c09103dff87bfb6916993a019f9309b363)
@@ -0,0 +1,90 @@
+/*
+ * Copyright (C) 2006 Jakub Jermar
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __BTREE_H__
+#define __BTREE_H__
+
+#include <arch/types.h>
+#include <typedefs.h>
+#include <adt/list.h>
+
+#define BTREE_M		4
+#define BTREE_MAX_KEYS	(BTREE_M - 1)
+
+/** B-tree node structure. */
+struct btree_node {
+	/** Number of keys. */
+	count_t keys;
+
+	/** Keys. We currently support only single keys. Additional room for one extra key is provided. */
+	__native key[BTREE_MAX_KEYS + 1];
+
+	/** 
+	 * Pointers to values. Sorted according to the key array. Defined only in leaf-level.
+	 * There is room for storing value for the extra key.
+	 */
+	void *value[BTREE_MAX_KEYS + 1];
+	
+	/**
+	 * Pointers to descendants of this node sorted according to the key array.
+	 * subtree[0] points to subtree with keys lesser than or equal to key[0].
+	 * subtree[1] points to subtree with keys greater than key[0] and lesser than or equal to key[1].
+	 * ...
+	 * There is room for storing a subtree pointer for the extra key.
+	 */
+	btree_node_t *subtree[BTREE_M + 1];
+
+	/** Pointer to parent node. Root node has NULL parent. */
+	btree_node_t *parent;
+
+	/** Link connecting leaf-level nodes. Defined only when this node is a leaf. */
+	link_t leaf_link;
+
+	/** Variables needed by btree_print(). */	
+	link_t bfs_link;
+	int depth;
+};
+
+/** B-tree structure. */
+struct btree {
+	btree_node_t *root;	/**< B-tree root node pointer. */
+	link_t leaf_head;	/**< Leaf-level list head. */
+};
+
+extern void btree_create(btree_t *t);
+extern void btree_destroy(btree_t *t);
+
+extern void btree_insert(btree_t *t, __native key, void *value, btree_node_t *leaf_node);
+extern void btree_remove(btree_t *t, __native key);
+extern void *btree_search(btree_t *t, __native key, btree_node_t **leaf_node);
+
+extern void *btree_node_min(btree_node_t *node);
+extern void *btree_node_max(btree_node_t *node);
+
+extern void btree_print(btree_t *t);
+#endif