mirror of
https://github.com/NLnetLabs/unbound.git
synced 2025-12-26 01:29:58 -05:00
105 lines
3.8 KiB
C
105 lines
3.8 KiB
C
/*
|
|
* rbtree.h -- generic red-black tree
|
|
*
|
|
* Copyright (c) 2001-2006, NLnet Labs. All rights reserved.
|
|
*
|
|
* Copyright (c) 2007, NLnet Labs. All rights reserved.
|
|
*
|
|
* This software is open source.
|
|
*
|
|
* 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.
|
|
*
|
|
* Neither the name of the NLNET LABS nor the names of its contributors may
|
|
* be used to endorse or promote products derived from this software without
|
|
* specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
* "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 REGENTS OR CONTRIBUTORS 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 _RBTREE_H_
|
|
#define _RBTREE_H_
|
|
|
|
#include "region-allocator.h"
|
|
|
|
/*
|
|
* This structure must be the first member of the data structure in
|
|
* the rbtree. This allows easy casting between an rbnode_t and the
|
|
* user data (poor man's inheritance).
|
|
*/
|
|
typedef struct rbnode_t rbnode_t;
|
|
struct rbnode_t {
|
|
rbnode_t *parent;
|
|
rbnode_t *left;
|
|
rbnode_t *right;
|
|
const void *key;
|
|
uint8_t color;
|
|
};
|
|
|
|
#define RBTREE_NULL &rbtree_null_node
|
|
extern rbnode_t rbtree_null_node;
|
|
|
|
typedef struct rbtree_t rbtree_t;
|
|
struct rbtree_t {
|
|
region_type *region;
|
|
|
|
/* The root of the red-black tree */
|
|
rbnode_t *root;
|
|
|
|
/* The number of the nodes in the tree */
|
|
size_t count;
|
|
|
|
/* Current node for walks... */
|
|
rbnode_t *_node;
|
|
|
|
/* Key compare function. <0,0,>0 like strcmp. Return 0 on two NULL ptrs. */
|
|
int (*cmp) (const void *, const void *);
|
|
};
|
|
|
|
/* rbtree.c */
|
|
rbtree_t *rbtree_create(region_type *region, int (*cmpf)(const void *, const void *));
|
|
rbnode_t *rbtree_insert(rbtree_t *rbtree, rbnode_t *data);
|
|
/* returns node that is now unlinked from the tree. User to delete it.
|
|
* returns 0 if node not present */
|
|
rbnode_t *rbtree_delete(rbtree_t *rbtree, const void *key);
|
|
rbnode_t *rbtree_search(rbtree_t *rbtree, const void *key);
|
|
/* returns true if exact match in result. Else result points to <= element,
|
|
or NULL if key is smaller than the smallest key. */
|
|
int rbtree_find_less_equal(rbtree_t *rbtree, const void *key, rbnode_t **result);
|
|
rbnode_t *rbtree_first(rbtree_t *rbtree);
|
|
rbnode_t *rbtree_last(rbtree_t *rbtree);
|
|
rbnode_t *rbtree_next(rbnode_t *rbtree);
|
|
rbnode_t *rbtree_previous(rbnode_t *rbtree);
|
|
|
|
#define RBTREE_WALK(rbtree, k, d) \
|
|
for((rbtree)->_node = rbtree_first(rbtree);\
|
|
(rbtree)->_node != RBTREE_NULL && ((k) = (rbtree)->_node->key) && \
|
|
((d) = (void *) (rbtree)->_node); (rbtree)->_node = rbtree_next((rbtree)->_node))
|
|
|
|
/* call with node=variable of struct* with rbnode_t as first element.
|
|
with type is the type of a pointer to that struct. */
|
|
#define RBTREE_FOR(node, type, rbtree) \
|
|
for(node=(type)rbtree_first(rbtree); \
|
|
(rbnode_t*)node != RBTREE_NULL; \
|
|
node = (type)rbtree_next((rbnode_t*)node))
|
|
|
|
#endif /* _RBTREE_H_ */
|