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Diffstat (limited to 'cpukit/score/src/coremsgflushwait.c')
-rw-r--r-- | cpukit/score/src/coremsgflushwait.c | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/cpukit/score/src/coremsgflushwait.c b/cpukit/score/src/coremsgflushwait.c new file mode 100644 index 0000000000..bda8143ffd --- /dev/null +++ b/cpukit/score/src/coremsgflushwait.c @@ -0,0 +1,70 @@ +/* + * 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. + * + * $Id$ + */ + +#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 + ); +} + |