| 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 |