Rev 1150 | Rev 1177 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 1101 | jermar | 1 | /* |
| 2 | * Copyright (C) 2006 Jakub Jermar |
||
| 3 | * All rights reserved. |
||
| 4 | * |
||
| 5 | * Redistribution and use in source and binary forms, with or without |
||
| 6 | * modification, are permitted provided that the following conditions |
||
| 7 | * are met: |
||
| 8 | * |
||
| 9 | * - Redistributions of source code must retain the above copyright |
||
| 10 | * notice, this list of conditions and the following disclaimer. |
||
| 11 | * - Redistributions in binary form must reproduce the above copyright |
||
| 12 | * notice, this list of conditions and the following disclaimer in the |
||
| 13 | * documentation and/or other materials provided with the distribution. |
||
| 14 | * - The name of the author may not be used to endorse or promote products |
||
| 15 | * derived from this software without specific prior written permission. |
||
| 16 | * |
||
| 17 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
||
| 18 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||
| 19 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
||
| 20 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
||
| 21 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||
| 22 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
||
| 23 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
||
| 24 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
||
| 25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
||
| 26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||
| 27 | */ |
||
| 28 | |||
| 29 | #ifndef __BTREE_H__ |
||
| 30 | #define __BTREE_H__ |
||
| 31 | |||
| 32 | #include <arch/types.h> |
||
| 33 | #include <typedefs.h> |
||
| 34 | #include <adt/list.h> |
||
| 35 | |||
| 1140 | jermar | 36 | #define BTREE_M 5 |
| 1101 | jermar | 37 | #define BTREE_MAX_KEYS (BTREE_M - 1) |
| 38 | |||
| 39 | /** B-tree node structure. */ |
||
| 40 | struct btree_node { |
||
| 41 | /** Number of keys. */ |
||
| 42 | count_t keys; |
||
| 43 | |||
| 44 | /** Keys. We currently support only single keys. Additional room for one extra key is provided. */ |
||
| 45 | __native key[BTREE_MAX_KEYS + 1]; |
||
| 46 | |||
| 47 | /** |
||
| 48 | * Pointers to values. Sorted according to the key array. Defined only in leaf-level. |
||
| 49 | * There is room for storing value for the extra key. |
||
| 50 | */ |
||
| 51 | void *value[BTREE_MAX_KEYS + 1]; |
||
| 52 | |||
| 53 | /** |
||
| 54 | * Pointers to descendants of this node sorted according to the key array. |
||
| 1140 | jermar | 55 | * subtree[0] points to subtree with keys lesser than to key[0]. |
| 56 | * subtree[1] points to subtree with keys greater than or equal to key[0] and lesser than key[1]. |
||
| 1101 | jermar | 57 | * ... |
| 58 | * There is room for storing a subtree pointer for the extra key. |
||
| 59 | */ |
||
| 60 | btree_node_t *subtree[BTREE_M + 1]; |
||
| 61 | |||
| 62 | /** Pointer to parent node. Root node has NULL parent. */ |
||
| 63 | btree_node_t *parent; |
||
| 64 | |||
| 65 | /** Link connecting leaf-level nodes. Defined only when this node is a leaf. */ |
||
| 66 | link_t leaf_link; |
||
| 67 | |||
| 68 | /** Variables needed by btree_print(). */ |
||
| 69 | link_t bfs_link; |
||
| 70 | int depth; |
||
| 71 | }; |
||
| 72 | |||
| 73 | /** B-tree structure. */ |
||
| 74 | struct btree { |
||
| 75 | btree_node_t *root; /**< B-tree root node pointer. */ |
||
| 76 | link_t leaf_head; /**< Leaf-level list head. */ |
||
| 77 | }; |
||
| 78 | |||
| 1164 | jermar | 79 | extern void btree_init(void); |
| 80 | |||
| 1101 | jermar | 81 | extern void btree_create(btree_t *t); |
| 82 | extern void btree_destroy(btree_t *t); |
||
| 83 | |||
| 84 | extern void btree_insert(btree_t *t, __native key, void *value, btree_node_t *leaf_node); |
||
| 1140 | jermar | 85 | extern void btree_remove(btree_t *t, __native key, btree_node_t *leaf_node); |
| 1101 | jermar | 86 | extern void *btree_search(btree_t *t, __native key, btree_node_t **leaf_node); |
| 87 | |||
| 1150 | jermar | 88 | extern btree_node_t *btree_leaf_node_left_neighbour(btree_t *t, btree_node_t *node); |
| 89 | extern btree_node_t *btree_leaf_node_right_neighbour(btree_t *t, btree_node_t *node); |
||
| 1147 | jermar | 90 | |
| 1101 | jermar | 91 | extern void btree_print(btree_t *t); |
| 92 | #endif |