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/**
* @file
*
* @ingroup POSIX_MQUEUE_P Message Queues Private Support Information
*
* @brief POSIX Message Queue Receive Support
*/
/*
* COPYRIGHT (c) 1989-2011.
* On-Line Applications Research Corporation (OAR).
*
* 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.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <rtems/posix/mqueueimpl.h>
#include <rtems/posix/posixapi.h>
#include <fcntl.h>
THREAD_QUEUE_OBJECT_ASSERT(
POSIX_Message_queue_Control,
Message_queue.Wait_queue,
POSIX_MESSAGE_QUEUE_CONTROL
);
/*
* _POSIX_Message_queue_Receive_support
*
* NOTE: XXX Document how size, priority, length, and the buffer go
* through the layers.
*/
ssize_t _POSIX_Message_queue_Receive_support(
mqd_t mqdes,
char *msg_ptr,
size_t msg_len,
unsigned int *msg_prio,
const struct timespec *abstime,
Thread_queue_Enqueue_callout enqueue_callout
)
{
POSIX_Message_queue_Control *the_mq;
Thread_queue_Context queue_context;
size_t length_out;
Thread_Control *executing;
Status_Control status;
the_mq = _POSIX_Message_queue_Get( mqdes, &queue_context );
if ( the_mq == NULL ) {
rtems_set_errno_and_return_minus_one( EBADF );
}
if ( ( the_mq->oflag & O_ACCMODE ) == O_WRONLY ) {
_ISR_lock_ISR_enable( &queue_context.Lock_context.Lock_context );
rtems_set_errno_and_return_minus_one( EBADF );
}
if ( msg_len < the_mq->Message_queue.maximum_message_size ) {
_ISR_lock_ISR_enable( &queue_context.Lock_context.Lock_context );
rtems_set_errno_and_return_minus_one( EMSGSIZE );
}
_Thread_queue_Context_set_enqueue_callout( &queue_context, enqueue_callout );
_Thread_queue_Context_set_timeout_argument( &queue_context, abstime );
/*
* Now if something goes wrong, we return a "length" of -1
* to indicate an error.
*/
length_out = -1;
_CORE_message_queue_Acquire_critical(
&the_mq->Message_queue,
&queue_context
);
if ( the_mq->open_count == 0 ) {
_CORE_message_queue_Release( &the_mq->Message_queue, &queue_context );
rtems_set_errno_and_return_minus_one( EBADF );
}
/*
* Now perform the actual message receive
*/
executing = _Thread_Executing;
status = _CORE_message_queue_Seize(
&the_mq->Message_queue,
executing,
msg_ptr,
&length_out,
( the_mq->oflag & O_NONBLOCK ) == 0,
&queue_context
);
if ( status != STATUS_SUCCESSFUL ) {
rtems_set_errno_and_return_minus_one( _POSIX_Get_error( status ) );
}
if ( msg_prio != NULL ) {
*msg_prio = _POSIX_Message_queue_Priority_from_core(
executing->Wait.count
);
}
return length_out;
}
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