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/*
* Copyright (c) 2011-2015 Richard Braun.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
*
* 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.
*
*
* Radix tree.
*
* In addition to the standard insertion operation, this implementation
* can allocate keys for the caller at insertion time.
*
* Upstream site with license notes :
* http://git.sceen.net/rbraun/librbraun.git/
*/
#ifndef _RDXTREE_H
#define _RDXTREE_H
#include <stddef.h>
#include <sys/types.h>
/*
* Initialize the node cache.
*/
void rdxtree_cache_init(void);
/*
* This macro selects between 32 or 64-bits (the default) keys.
*/
#if 0
#define RDXTREE_KEY_32
#endif
#ifdef RDXTREE_KEY_32
typedef uint32_t rdxtree_key_t;
#else /* RDXTREE_KEY_32 */
typedef uint64_t rdxtree_key_t;
#endif /* RDXTREE_KEY_32 */
/*
* Radix tree.
*/
struct rdxtree;
/*
* Radix tree iterator.
*/
struct rdxtree_iter;
/*
* Static tree initializer.
*/
#define RDXTREE_INITIALIZER { 0, NULL }
#include "rdxtree_i.h"
/*
* Initialize a tree.
*/
static inline void
rdxtree_init(struct rdxtree *tree)
{
tree->height = 0;
tree->root = NULL;
}
/*
* Insert a pointer in a tree.
*
* The ptr parameter must not be NULL.
*/
static inline int
rdxtree_insert(struct rdxtree *tree, rdxtree_key_t key, void *ptr)
{
return rdxtree_insert_common(tree, key, ptr, NULL);
}
/*
* Insert a pointer in a tree and obtain its slot.
*
* The ptr and slotp parameters must not be NULL. If successful, the slot of
* the newly inserted pointer is stored at the address pointed to by the slotp
* parameter.
*/
static inline int
rdxtree_insert_slot(struct rdxtree *tree, rdxtree_key_t key,
void *ptr, void ***slotp)
{
return rdxtree_insert_common(tree, key, ptr, slotp);
}
/*
* Insert a pointer in a tree, for which a new key is allocated.
*
* The ptr and keyp parameters must not be NULL. The newly allocated key is
* stored at the address pointed to by the keyp parameter.
*/
static inline int
rdxtree_insert_alloc(struct rdxtree *tree, void *ptr, rdxtree_key_t *keyp)
{
return rdxtree_insert_alloc_common(tree, ptr, keyp, NULL);
}
/*
* Insert a pointer in a tree, for which a new key is allocated, and obtain
* its slot.
*
* The ptr, keyp and slotp parameters must not be NULL. The newly allocated
* key is stored at the address pointed to by the keyp parameter while the
* slot of the inserted pointer is stored at the address pointed to by the
* slotp parameter.
*/
static inline int
rdxtree_insert_alloc_slot(struct rdxtree *tree, void *ptr,
rdxtree_key_t *keyp, void ***slotp)
{
return rdxtree_insert_alloc_common(tree, ptr, keyp, slotp);
}
/*
* Remove a pointer from a tree.
*
* The matching pointer is returned if successful, NULL otherwise.
*/
void * rdxtree_remove(struct rdxtree *tree, rdxtree_key_t key);
/*
* Look up a pointer in a tree.
*
* The matching pointer is returned if successful, NULL otherwise.
*/
static inline void *
rdxtree_lookup(const struct rdxtree *tree, rdxtree_key_t key)
{
return rdxtree_lookup_common(tree, key, 0);
}
/*
* Look up a slot in a tree.
*
* A slot is a pointer to a stored pointer in a tree. It can be used as
* a placeholder for fast replacements to avoid multiple lookups on the same
* key.
*
* A slot for the matching pointer is returned if successful, NULL otherwise.
*
* See rdxtree_replace_slot().
*/
static inline void **
rdxtree_lookup_slot(const struct rdxtree *tree, rdxtree_key_t key)
{
return rdxtree_lookup_common(tree, key, 1);
}
/*
* Replace a pointer in a tree.
*
* The ptr parameter must not be NULL. The previous pointer is returned.
*
* See rdxtree_lookup_slot().
*/
void * rdxtree_replace_slot(void **slot, void *ptr);
/*
* Forge a loop to process all pointers of a tree.
*/
#define rdxtree_for_each(tree, iter, ptr) \
for (rdxtree_iter_init(iter), ptr = rdxtree_walk(tree, iter); \
ptr != NULL; \
ptr = rdxtree_walk(tree, iter))
/*
* Return the key of the current pointer from an iterator.
*/
static inline rdxtree_key_t
rdxtree_iter_key(const struct rdxtree_iter *iter)
{
return iter->key;
}
/*
* Remove all pointers from a tree.
*
* The common way to destroy a tree and its pointers is to loop over all
* the pointers using rdxtree_for_each(), freeing them, then call this
* function.
*/
void rdxtree_remove_all(struct rdxtree *tree);
#endif /* _RDXTREE_H */
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