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/*

 *  CORE Message Queue Handler

 *

 *  DESCRIPTION:

 *

 *  This package is the implementation of the CORE Message Queue Handler.

 *  This core object provides task synchronization and communication functions

 *  via messages passed to queue objects.

 *

 *  COPYRIGHT (c) 1989-1999.

 *  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.OARcorp.com/rtems/license.html.

 *

 *  $Id: coremsgflushwait.c,v 1.2 2001-09-27 11:59:34 chris Exp $

 */

#include <rtems/system.h>

#include <rtems/score/chain.h>

#include <rtems/score/isr.h>

#include <rtems/score/object.h>

#include <rtems/score/coremsg.h>

#include <rtems/score/states.h>

#include <rtems/score/thread.h>

#include <rtems/score/wkspace.h>

#if defined(RTEMS_MULTIPROCESSING)

#include <rtems/score/mpci.h>

#endif

/*PAGE

 *

 *  _CORE_message_queue_Flush_waiting_threads

 *

 *  This function flushes the message_queue's task wait queue.  The number

 *  of messages flushed from the queue is returned.

 *

 *  Input parameters:

 *    the_message_queue - the message_queue to be flushed

 *

 *  Output parameters:

 *    returns - the number of messages flushed from the queue

 */

void _CORE_message_queue_Flush_waiting_threads(

  CORE_message_queue_Control *the_message_queue

)

{

  /* XXX this is not supported for global message queues */

  /*

   *  IF there are no pending messages,

   *  THEN threads may be blocked waiting to RECEIVE a message,

   *

   *  IF the pending message queue is full

   *  THEN threads may be blocked waiting to SEND a message

   *

   *  But in either case, we will return "unsatisfied nowait"

   *  to indicate that the blocking condition was not satisfied

   *  and that the blocking state was canceled.

   */

  _Thread_queue_Flush(

    &the_message_queue->Wait_queue,

    NULL,

    CORE_MESSAGE_QUEUE_STATUS_UNSATISFIED_NOWAIT

  );

}