score/src/chain.c

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /**
0004  * @file
0005  *
0006  * @ingroup RTEMSScoreChain
0007  *
0008  * @brief This source file contains the implementation of
0009  *   _Chain_Initialize().
0010  */
0011
0012 /*
0013  *  COPYRIGHT (c) 1989-2007.
0014  *  On-Line Applications Research Corporation (OAR).
0015  *
0016  * Redistribution and use in source and binary forms, with or without
0017  * modification, are permitted provided that the following conditions
0018  * are met:
0019  * 1. Redistributions of source code must retain the above copyright
0020  *    notice, this list of conditions and the following disclaimer.
0021  * 2. Redistributions in binary form must reproduce the above copyright
0022  *    notice, this list of conditions and the following disclaimer in the
0023  *    documentation and/or other materials provided with the distribution.
0024  *
0025  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0026  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0027  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0028  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0029  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0030  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0031  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0032  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0033  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0034  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0035  * POSSIBILITY OF SUCH DAMAGE.
0036  */
0037
0038 #ifdef HAVE_CONFIG_H
0039 #include "config.h"
0040 #endif
0041
0042 #include <rtems/score/chainimpl.h>
0043 #include <rtems/score/address.h>
0044 #include <rtems/score/assert.h>
0045
0046 void _Chain_Initialize(
0047   Chain_Control *the_chain,
0048   void           *starting_address,
0049   size_t         number_nodes,
0050   size_t         node_size
0051 )
0052 {
0053   size_t count = number_nodes;
0054   Chain_Node *head = _Chain_Head( the_chain );
0055   Chain_Node *tail = _Chain_Tail( the_chain );
0056   Chain_Node *current = head;
0057   Chain_Node *next = starting_address;
0058
0059   _Assert( node_size >= sizeof( *next ) );
0060
0061   head->previous = NULL;
0062
0063   while ( count-- ) {
0064     current->next  = next;
0065     next->previous = current;
0066     current        = next;
0067     next           = (Chain_Node *)
0068                         _Addresses_Add_offset( (void *) next, node_size );
0069   }
0070
0071   current->next = tail;
0072   tail->previous = current;
0073 }