incubator-nuttx/sched/mqueue/mq_setattr.c

84 lines
2.7 KiB
C

/****************************************************************************
* sched/mqueue/mq_setattr.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <fcntl.h> /* O_NONBLOCK */
#include <mqueue.h>
#include <nuttx/mqueue.h>
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: 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()).
*
* Input Parameters:
* mqdes - Message queue descriptor
* mq_stat - New attributes
* oldstate - Old attributes
*
* Returned 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)
{
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;
}