/* SPDX-License-Identifier: BSD-2-Clause */
/**
* @file
*
* @ingroup RTEMSAPIClassicRBTrees
*
* @brief This header file provides the Red-Black Trees API.
*/
/*
* Copyright (c) 2010 Gedare Bloom.
*
* 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 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 COPYRIGHT OWNER 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 _RTEMS_RBTREE_H
#define _RTEMS_RBTREE_H
#include <rtems/score/rbtree.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* @defgroup RTEMSAPIRBTrees Red-Black Trees
*
* @ingroup RTEMSAPIClassic
*
* @brief The red-black tree container provides data structures and directives
* to manage user-defined data structures in red-black trees.
*
* The red-black tree container offers no internal protection against
* concurrent access. The user must ensure that at most one thread at once can
* access a red-black tree instance.
*
* @{
*/
/**
* @typedef rtems_rbtree_node
*
* A node that can be manipulated in the rbtree.
*/
typedef RBTree_Node rtems_rbtree_node;
/**
* @typedef rtems_rbtree_control
*
* The rbtree's control anchors the rbtree.
*/
typedef RBTree_Control rtems_rbtree_control;
/**
* @brief Integer type for compare results.
*
* The type is large enough to represent pointers and 32-bit signed integers.
*
* @see rtems_rbtree_compare.
*/
typedef long rtems_rbtree_compare_result;
/**
* @brief Compares two red-black tree nodes.
*
* @param[in] first The first node.
* @param[in] second The second node.
*
* @retval positive The key value of the first node is greater than the one of
* the second node.
* @retval 0 The key value of the first node is equal to the one of the second
* node.
* @retval negative The key value of the first node is less than the one of the
* second node.
*/
typedef rtems_rbtree_compare_result ( *rtems_rbtree_compare )(
const RBTree_Node *first,
const RBTree_Node *second
);
/**
* @brief RBTree initializer for an empty rbtree with designator @a name.
*/
#define RTEMS_RBTREE_INITIALIZER_EMPTY(name) \
RBTREE_INITIALIZER_EMPTY(name)
/**
* @brief RBTree definition for an empty rbtree with designator @a name.
*/
#define RTEMS_RBTREE_DEFINE_EMPTY(name) \
RBTREE_DEFINE_EMPTY(name)
/**
* @brief Initialize a RBTree header.
*
* This routine initializes @a the_rbtree structure to manage the
* contiguous array of @a number_nodes nodes which starts at
* @a starting_address. Each node is of @a node_size bytes.
*
* @param[in] the_rbtree is the pointer to rbtree header
* @param[in] compare The node compare function.
* @param[in] starting_address is the starting address of first node
* @param[in] number_nodes is the number of nodes in rbtree
* @param[in] node_size is the size of node in bytes
* @param[in] is_unique If true, then reject nodes with a duplicate key, else
* otherwise.
*/
void rtems_rbtree_initialize(
rtems_rbtree_control *the_rbtree,
rtems_rbtree_compare compare,
void *starting_address,
size_t number_nodes,
size_t node_size,
bool is_unique
);
/**
* @brief Initialize this RBTree as Empty
*
* This routine initializes @a the_rbtree to contain zero nodes.
*/
static inline void rtems_rbtree_initialize_empty(
rtems_rbtree_control *the_rbtree
)
{
_RBTree_Initialize_empty( the_rbtree );
}
/**
* @brief Set off RBtree.
*
* This function sets the next and previous fields of the @a node to NULL
* indicating the @a node is not part of any rbtree.
*/
static inline void rtems_rbtree_set_off_tree(
rtems_rbtree_node *node
)
{
_RBTree_Set_off_tree( node );
}
/**
* @brief Is the Node off RBTree.
*
* This function returns true if the @a node is not on a rbtree. A @a node is
* off rbtree if the next and previous fields are set to NULL.
*/
static inline bool rtems_rbtree_is_node_off_tree(
const rtems_rbtree_node *node
)
{
return _RBTree_Is_node_off_tree( node );
}
/**
* @brief Return pointer to RBTree root.
*
* This function returns a pointer to the root node of @a the_rbtree.
*/
static inline rtems_rbtree_node *rtems_rbtree_root(
const rtems_rbtree_control *the_rbtree
)
{
return _RBTree_Root( the_rbtree );
}
/**
* @copydoc _RBTree_Minimum()
*/
static inline rtems_rbtree_node *rtems_rbtree_min(
const rtems_rbtree_control *the_rbtree
)
{
return _RBTree_Minimum( the_rbtree );
}
/**
* @copydoc _RBTree_Maximum()
*/
static inline rtems_rbtree_node *rtems_rbtree_max(
const rtems_rbtree_control *the_rbtree
)
{
return _RBTree_Maximum( the_rbtree );
}
/**
* @brief Return pointer to the left child node from this node.
*
* This function returns a pointer to the left child node of @a the_node.
*/
static inline rtems_rbtree_node *rtems_rbtree_left(
const rtems_rbtree_node *the_node
)
{
return _RBTree_Left( the_node );
}
/**
* @brief Return pointer to the right child node from this node.
*
* This function returns a pointer to the right child node of @a the_node.
*/
static inline rtems_rbtree_node *rtems_rbtree_right(
const rtems_rbtree_node *the_node
)
{
return _RBTree_Right( the_node );
}
/**
* @copydoc _RBTree_Parent()
*/
static inline rtems_rbtree_node *rtems_rbtree_parent(
const rtems_rbtree_node *the_node
)
{
return _RBTree_Parent( the_node );
}
/**
* @brief Is the RBTree empty.
*
* This function returns true if there a no nodes on @a the_rbtree and
* false otherwise.
*/
static inline bool rtems_rbtree_is_empty(
const rtems_rbtree_control *the_rbtree
)
{
return _RBTree_Is_empty( the_rbtree );
}
/**
* @brief Is this the minimum node on the RBTree.
*
* This function returns true if @a the_node is the min node on @a the_rbtree
* and false otherwise.
*/
static inline bool rtems_rbtree_is_min(
const rtems_rbtree_control *the_rbtree,
const rtems_rbtree_node *the_node
)
{
return rtems_rbtree_min( the_rbtree ) == the_node;
}
/**
* @brief Is this the maximum node on the RBTree.
*
* This function returns true if @a the_node is the max node on @a the_rbtree
* and false otherwise.
*/
static inline bool rtems_rbtree_is_max(
const rtems_rbtree_control *the_rbtree,
const rtems_rbtree_node *the_node
)
{
return rtems_rbtree_max( the_rbtree ) == the_node;
}
/**
* @copydoc _RBTree_Is_root()
*/
static inline bool rtems_rbtree_is_root(
const rtems_rbtree_node *the_node
)
{
return _RBTree_Is_root( the_node );
}
static inline bool rtems_rbtree_is_equal(
rtems_rbtree_compare_result compare_result
)
{
return compare_result == 0;
}
static inline bool rtems_rbtree_is_greater(
rtems_rbtree_compare_result compare_result
)
{
return compare_result > 0;
}
static inline bool rtems_rbtree_is_lesser(
rtems_rbtree_compare_result compare_result
)
{
return compare_result < 0;
}
/**
* @brief Tries to find a node for the specified key in the tree.
*
* @param[in] the_rbtree The red-black tree control.
* @param[in] the_node A node specifying the key.
* @param[in] compare The node compare function.
* @param[in] is_unique If true, then return the first node with a key equal to
* the one of the node specified if it exits, else return the last node if it
* exists.
*
* @retval node A node corresponding to the key. If the tree is not unique
* and contains duplicate keys, the set of duplicate keys acts as FIFO.
* @retval NULL No node exists in the tree for the key.
*/
rtems_rbtree_node* rtems_rbtree_find(
const rtems_rbtree_control *the_rbtree,
const rtems_rbtree_node *the_node,
rtems_rbtree_compare compare,
bool is_unique
);
/**
* @copydoc _RBTree_Predecessor()
*/
static inline rtems_rbtree_node* rtems_rbtree_predecessor(
const rtems_rbtree_node *node
)
{
return _RBTree_Predecessor( node );
}
/**
* @copydoc _RBTree_Successor()
*/
static inline rtems_rbtree_node* rtems_rbtree_successor(
const rtems_rbtree_node *node
)
{
return _RBTree_Successor( node );
}
/**
* @copydoc _RBTree_Extract()
*/
static inline void rtems_rbtree_extract(
rtems_rbtree_control *the_rbtree,
rtems_rbtree_node *the_node
)
{
_RBTree_Extract( the_rbtree, the_node );
}
/**
* @brief Gets a node with the minimum key value from the red-black tree.
*
* This function extracts a node with the minimum key value from
* tree and returns a pointer to that node if it exists. In case multiple
* nodes with a minimum key value exist, then they are extracted in FIFO order.
*
* @param[in] the_rbtree The red-black tree control.
*
* @retval NULL The tree is empty.
* @retval node A node with the minimal key value on the tree.
*/
static inline rtems_rbtree_node *rtems_rbtree_get_min(
rtems_rbtree_control *the_rbtree
)
{
rtems_rbtree_node *the_node = rtems_rbtree_min( the_rbtree );
if ( the_node != NULL ) {
rtems_rbtree_extract( the_rbtree, the_node );
}
return the_node;
}
/**
* @brief Gets a node with the maximal key value from the red-black tree.
*
* This function extracts a node with the maximum key value from tree and
* returns a pointer to that node if it exists. In case multiple nodes with a
* maximum key value exist, then they are extracted in LIFO order.
*
* @param[in] the_rbtree The red-black tree control.
*
* @retval NULL The tree is empty.
* @retval node A node with the maximal key value on the tree.
*/
static inline rtems_rbtree_node *rtems_rbtree_get_max(
rtems_rbtree_control *the_rbtree
)
{
rtems_rbtree_node *the_node = rtems_rbtree_max( the_rbtree );
if ( the_node != NULL ) {
rtems_rbtree_extract( the_rbtree, the_node );
}
return the_node;
}
/**
* @brief Peek at the min node on a rbtree.
*
* This function returns a pointer to the min node from @a the_rbtree
* without changing the tree. If @a the_rbtree is empty,
* then NULL is returned.
*/
static inline rtems_rbtree_node *rtems_rbtree_peek_min(
const rtems_rbtree_control *the_rbtree
)
{
return rtems_rbtree_min( the_rbtree );
}
/**
* @brief Peek at the max node on a rbtree.
*
* This function returns a pointer to the max node from @a the_rbtree
* without changing the tree. If @a the_rbtree is empty,
* then NULL is returned.
*/
static inline rtems_rbtree_node *rtems_rbtree_peek_max(
const rtems_rbtree_control *the_rbtree
)
{
return rtems_rbtree_max( the_rbtree );
}
/**
* @brief Inserts the node into the red-black tree.
*
* In case the node is already a node of a tree, then this function yields
* unpredictable results.
*
* @param[in] the_rbtree The red-black tree control.
* @param[in] the_node The node to insert.
* @param[in] compare The node compare function.
* @param[in] is_unique If true, then reject nodes with a duplicate key, else
* insert nodes in FIFO order in case the key value is equal to existing nodes.
*
* @retval NULL Successfully inserted.
* @retval existing_node This is a unique insert and there exists a node with
* an equal key in the tree already.
*/
rtems_rbtree_node *rtems_rbtree_insert(
RBTree_Control *the_rbtree,
RBTree_Node *the_node,
rtems_rbtree_compare compare,
bool is_unique
);
/** @} */
#ifdef __cplusplus
}
#endif
#endif
/* end of include file */
