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/*
* NOTE: The structure of the routines is identical to that of POSIX
* Message_queues to leave the option of having unnamed message
* queues at a future date. They are currently not part of the
* POSIX standard but unnamed message_queues are. This is also
* the reason for the apparently unnecessary tracking of
* the process_shared attribute. [In addition to the fact that
* it would be trivial to add pshared to the mq_attr structure
* and have process private message queues.]
*
* This code ignores the O_RDONLY/O_WRONLY/O_RDWR flag at open
* time.
*
* COPYRIGHT (c) 1989-2009.
* 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.com/license/LICENSE.
*
* $Id$
*/
#if HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include <stdarg.h>
#include <stdlib.h>
#include <pthread.h>
#include <limits.h>
#include <errno.h>
#include <fcntl.h>
#include <mqueue.h>
#include <rtems/system.h>
#include <rtems/score/watchdog.h>
#include <rtems/score/wkspace.h>
#include <rtems/seterr.h>
#include <rtems/posix/mqueue.h>
#include <rtems/posix/time.h>
/* pure ANSI mode does not have this prototype */
size_t strnlen(const char *, size_t);
/*
* _POSIX_Message_queue_Create_support
*
* This routine does the actual creation and initialization of
* a poxix message queue.
*/
int _POSIX_Message_queue_Create_support(
const char *name_arg,
int pshared,
struct mq_attr *attr_ptr,
POSIX_Message_queue_Control **message_queue
)
{
POSIX_Message_queue_Control *the_mq;
CORE_message_queue_Attributes *the_mq_attr;
struct mq_attr attr;
char *name;
size_t n;
n = strnlen( name_arg, NAME_MAX );
/* length of name has already been validated */
_Thread_Disable_dispatch();
/*
* There is no real basis for the default values. They will work
* but were not compared against any existing implementation for
* compatibility. See README.mqueue for an example program we
* think will print out the defaults. Report anything you find with it.
*/
if ( attr_ptr == NULL ) {
attr.mq_maxmsg = 10;
attr.mq_msgsize = 16;
} else {
if ( attr_ptr->mq_maxmsg <= 0 ){
_Thread_Enable_dispatch();
rtems_set_errno_and_return_minus_one( EINVAL );
}
if ( attr_ptr->mq_msgsize <= 0 ){
_Thread_Enable_dispatch();
rtems_set_errno_and_return_minus_one( EINVAL );
}
attr = *attr_ptr;
}
the_mq = _POSIX_Message_queue_Allocate();
if ( !the_mq ) {
_Thread_Enable_dispatch();
rtems_set_errno_and_return_minus_one( ENFILE );
}
the_mq->process_shared = pshared;
the_mq->named = true;
the_mq->open_count = 1;
the_mq->linked = true;
/*
* Make a copy of the user's string for name just in case it was
* dynamically constructed.
*/
name = _Workspace_Allocate(n+1);
if (!name) {
_POSIX_Message_queue_Free( the_mq );
_Thread_Enable_dispatch();
rtems_set_errno_and_return_minus_one( ENOMEM );
}
strncpy( name, name_arg, n+1 );
/*
* NOTE: That thread blocking discipline should be based on the
* current scheduling policy.
*
* Joel: Cite POSIX or OpenGroup on above statement so we can determine
* if it is a real requirement.
*/
the_mq_attr = &the_mq->Message_queue.Attributes;
the_mq_attr->discipline = CORE_MESSAGE_QUEUE_DISCIPLINES_FIFO;
if ( !_CORE_message_queue_Initialize(
&the_mq->Message_queue,
the_mq_attr,
attr.mq_maxmsg,
attr.mq_msgsize
) ) {
_POSIX_Message_queue_Free( the_mq );
_Workspace_Free(name);
_Thread_Enable_dispatch();
rtems_set_errno_and_return_minus_one( ENOSPC );
}
_Objects_Open_string(
&_POSIX_Message_queue_Information,
&the_mq->Object,
name
);
*message_queue = the_mq;
_Thread_Enable_dispatch();
return 0;
}
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