shared/shmdr/shmdr-getpkt.c

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /*  Shm_Get_packet
0004  *
0005  *  This routine is the shared memory locked queue MPCI driver
0006  *  routine used to obtain an empty message packet.
0007  *
0008  *  Input parameters:
0009  *    packet             - address of pointer to packet
0010  *
0011  *  Output parameters:
0012  *    *(cpb->get_packet) - address of allocated packet
0013  *
0014  *  COPYRIGHT (c) 1989-1999.
0015  *  On-Line Applications Research Corporation (OAR).
0016  *
0017  * Redistribution and use in source and binary forms, with or without
0018  * modification, are permitted provided that the following conditions
0019  * are met:
0020  * 1. Redistributions of source code must retain the above copyright
0021  *    notice, this list of conditions and the following disclaimer.
0022  * 2. Redistributions in binary form must reproduce the above copyright
0023  *    notice, this list of conditions and the following disclaimer in the
0024  *    documentation and/or other materials provided with the distribution.
0025  *
0026  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0027  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0028  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0029  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0030  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0031  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0032  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0033  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0034  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0035  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0036  * POSSIBILITY OF SUCH DAMAGE.
0037  */
0038
0039 #include <rtems.h>
0040 #include "shm_driver.h"
0041
0042 rtems_mpci_entry Shm_Get_packet(
0043   rtems_packet_prefix **packet
0044 )
0045 {
0046   Shm_Envelope_control *ecb;
0047
0048   ecb = Shm_Allocate_envelope();
0049   if ( !ecb )
0050     rtems_fatal_error_occurred ( SHM_NO_FREE_PKTS );
0051   *packet = Shm_Envelope_control_to_packet_prefix_pointer( ecb );
0052 }