/************************************************************
* mq_setattr.c
*
* Copyright (C) 2007 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* 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.
* 3. Neither the name Gregory Nutt nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* 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.
*
************************************************************/
/************************************************************
* Included Files
************************************************************/
#include <sys/types.h> /* uint32, etc. */
#include <fcntl.h> /* O_NONBLOCK */
#include <mqueue.h>
#include "mq_internal.h"
/************************************************************
* Definitions
************************************************************/
/************************************************************
* Private Type Declarations
************************************************************/
/************************************************************
* Global Variables
************************************************************/
/************************************************************
* Private Variables
************************************************************/
/************************************************************
* Private Functions
************************************************************/
/************************************************************
* Public Functions
************************************************************/
/************************************************************
* Function: mq_setattr
*
* Description:
* This function sets the attributes associated with the
* specified message queue "mqdes." Only the "O_NONBLOCK"
* bit of the "mq_flags" can be changed.
*
* If "oldstat" is non-null, mq_setattr() will store the
* previous message queue attributes at that location (just
* as would have been returned by mq_getattr()).
*
* Parameters:
* mqdes - Message queue descriptor
* mq_stat - New attributes
* oldstate - Old attributes
*
* Return Value:
* 0 (OK) if attributes are set successfully, otherwise
* -1 (ERROR).
*
* Assumptions:
*
************************************************************/
int mq_setattr(mqd_t mqdes, const struct mq_attr *mq_stat,
struct mq_attr *oldstat)
{
int ret = ERROR;
if (mqdes && mq_stat)
{
/* Return the attributes if so requested */
if (oldstat)
{
(void)mq_getattr(mqdes, oldstat);
}
/* Set the new value of the O_NONBLOCK flag. */
mqdes->oflags = ((mq_stat->mq_flags & O_NONBLOCK) |
(mqdes->oflags & (~O_NONBLOCK)));
ret = OK;
}
return ret;
}
