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 |