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/**
* @file
*
* @brief Inlined Routines Associated with Red-Black Trees
*
* This include file contains the bodies of the routines which are
* associated with Red-Black Trees and inlined.
*
* @note The routines in this file are ordered from simple
* to complex. No other RBTree Handler routine is referenced
* unless it has already been defined.
*/
/*
* Copyright (c) 2010-2012 Gedare Bloom.
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#ifndef _RTEMS_SCORE_RBTREEIMPL_H
#define _RTEMS_SCORE_RBTREEIMPL_H
#include <rtems/score/rbtree.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* @addtogroup ScoreRBTree
*/
/**@{**/
/**
* @brief Red-black tree visitor.
*
* @param[in] node The node.
* @param[in] visitor_arg The visitor argument.
*
* @retval true Stop the iteration.
* @retval false Continue the iteration.
*
* @see _RBTree_Iterate().
*/
typedef bool (*RBTree_Visitor)(
const RBTree_Node *node,
void *visitor_arg
);
/**
* @brief Red-black tree iteration.
*
* @param[in] rbtree The red-black tree.
* @param[in] visitor The visitor.
* @param[in] visitor_arg The visitor argument.
*/
void _RBTree_Iterate(
const RBTree_Control *rbtree,
RBTree_Visitor visitor,
void *visitor_arg
);
/**
* @brief Get the direction opposite to @a the_dir.
*/
RTEMS_INLINE_ROUTINE RBTree_Direction _RBTree_Opposite_direction(
RBTree_Direction the_dir
)
{
return (RBTree_Direction) !((int) the_dir);
}
/**
* @brief Returns the direction of the node.
*
* @param[in] the_node The node of interest.
* @param[in] parent The parent of the node. The parent must exist, thus it is
* invalid to use this function for the root node.
*/
RTEMS_INLINE_ROUTINE RBTree_Direction _RBTree_Direction(
const RBTree_Node *the_node,
const RBTree_Node *parent
)
{
return (RBTree_Direction) ( the_node != parent->child[ 0 ] );
}
/**
* @brief Is this node red.
*
* This function returns true if @a the_node is red and false otherwise.
*
* @retval true @a the_node is red.
* @retval false @a the_node in not red.
*/
RTEMS_INLINE_ROUTINE bool _RBTree_Is_red(
const RBTree_Node *the_node
)
{
return (the_node && the_node->color == RBT_RED);
}
/**
* @brief Returns the sibling of the node.
*
* @param[in] the_node The node of interest.
* @param[in] parent The parent of the node. The parent must exist, thus it is
* invalid to use this function for the root node.
*
* @retval NULL No sibling exists.
* @retval sibling The sibling of the node.
*/
RTEMS_INLINE_ROUTINE RBTree_Node *_RBTree_Sibling(
const RBTree_Node *the_node,
const RBTree_Node *parent
)
{
RBTree_Node *left_child = parent->child[ RBT_LEFT ];
return the_node == left_child ? parent->child[ RBT_RIGHT ] : left_child;
}
RTEMS_INLINE_ROUTINE bool _RBTree_Is_equal(
RBTree_Compare_result compare_result
)
{
return compare_result == 0;
}
RTEMS_INLINE_ROUTINE bool _RBTree_Is_greater(
RBTree_Compare_result compare_result
)
{
return compare_result > 0;
}
RTEMS_INLINE_ROUTINE bool _RBTree_Is_lesser(
RBTree_Compare_result compare_result
)
{
return compare_result < 0;
}
/**
* @brief Rotates the node in the specified direction.
*
* The node is swapped with its child in the opposite direction if it exists.
*
* Sub-tree before rotation:
* @dot
* digraph state {
* parent -> the_node;
* the_node -> sibling [label="dir"];
* the_node -> child [label="opp_dir"];
* child -> grandchild [label="dir"];
* child -> grandchildsibling [label="opp_dir"];
* }
* @enddot
*
* Sub-tree after rotation:
* @dot
* digraph state {
* parent -> child;
* the_node -> sibling [label="dir"];
* the_node -> grandchild [label="opp_dir"];
* child -> the_node [label="dir"];
* child -> grandchildsibling [label="opp_dir"];
* }
* @enddot
*
* @param[in] the_node The node to rotate.
* @param[in] dir The rotation direction.
*/
RTEMS_INLINE_ROUTINE void _RBTree_Rotate(
RBTree_Node *the_node,
RBTree_Direction dir
)
{
RBTree_Direction opp_dir = _RBTree_Opposite_direction( dir );
RBTree_Node *child = the_node->child[ opp_dir ];
RBTree_Node *grandchild;
RBTree_Node *parent;
if ( child == NULL)
return;
grandchild = child->child[ dir ];
the_node->child[ opp_dir ] = grandchild;
if ( grandchild != NULL )
grandchild->parent = the_node;
child->child[ dir ] = the_node;
parent = _RBTree_Parent( the_node );
parent->child[ _RBTree_Direction( the_node, parent ) ] = child;
child->parent = parent;
the_node->parent = child;
}
/** @} */
#ifdef __cplusplus
}
#endif
#endif
/* end of include file */
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