blob: 17b655d7d5113899fe64d206335074c4ef3f9e76 (
plain) (
tree)
|
|
/* event.h
*
* This include file contains the information pertaining to the Event
* Manager. This manager provides a high performance method of communication
* and synchronization.
*
* Directives provided are:
*
* + send an event set to a task
* + receive event condition
*
*
* 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.
*
* $Id$
*/
#ifndef __RTEMS_EVENT_h
#define __RTEMS_EVENT_h
#ifdef __cplusplus
extern "C" {
#endif
#include <rtems/score/object.h>
#include <rtems/rtems/types.h>
#include <rtems/rtems/options.h>
#include <rtems/score/thread.h>
#include <rtems/score/watchdog.h>
#include <rtems/rtems/eventset.h>
/*
* This constant is passed as the event_in to the
* rtems_event_receive directive to determine which events are pending.
*/
#define EVENT_CURRENT 0
/*
* The following enumerated types indicate what happened while the event
* manager was in the synchronization window.
*/
typedef enum {
EVENT_SYNC_SYNCHRONIZED,
EVENT_SYNC_NOTHING_HAPPENED,
EVENT_SYNC_TIMEOUT,
EVENT_SYNC_SATISFIED
} Event_Sync_states;
/*
* Event_Manager_initialization
*
* DESCRIPTION:
*
* This routine performs the initialization necessary for this manager.
*/
void _Event_Manager_initialization( void );
/*
* rtems_event_send
*
* DESCRIPTION:
*
* This routine implements the rtems_event_send directive. It sends
* event_in to the task specified by ID. If the task is blocked
* waiting to receive events and the posting of event_in satisfies
* the task's event condition, then it is unblocked.
*/
rtems_status_code rtems_event_send (
Objects_Id id,
rtems_event_set event_in
);
/*
* rtems_event_receive
*
* DESCRIPTION:
*
* This routine implements the rtems_event_receive directive. This
* directive is invoked when the calling task wishes to receive
* the event_in event condition. One of the fields in the option_set
* parameter determines whether the receive request is satisfied if
* any or all of the events are pending. If the event condition
* is not satisfied immediately, then the task may block with an
* optional timeout of TICKS clock ticks or return immediately.
* This determination is based on another field in the option_set
* parameter. This directive returns the events received in the
* event_out parameter.
*/
rtems_status_code rtems_event_receive (
rtems_event_set event_in,
rtems_option option_set,
rtems_interval ticks,
rtems_event_set *event_out
);
/*
* _Event_Seize
*
* DESCRIPTION:
*
* This routine determines if the event condition event_in is
* satisfied. If so or if the no_wait option is enabled in option_set,
* then the procedure returns immediately. If neither of these
* conditions is true, then the calling task is blocked with an
* optional timeout of ticks clock ticks.
*/
void _Event_Seize (
rtems_event_set event_in,
rtems_option option_set,
rtems_interval ticks,
rtems_event_set *event_out
);
/*
* _Event_Surrender
*
* DESCRIPTION:
*
* This routine determines if the event condition of the_thread
* has been satisfied. If so, it unblocks the_thread.
*/
void _Event_Surrender (
Thread_Control *the_thread
);
/*
* _Event_Timeout
*
* DESCRIPTION:
*
* This routine is invoked when a task's event receive request
* has not been satisfied after the specified timeout interval.
* The task represented by ID will be unblocked and its status
* code will be set in it's control block to indicate that a timeout
* has occurred.
*/
void _Event_Timeout (
Objects_Id id,
void *ignored
);
/*
* The following defines the synchronization flag used by the
* Event Manager to insure that signals sent to the currently
* executing thread are received properly.
*/
RTEMS_EXTERN volatile Event_Sync_states _Event_Sync_state;
#if defined(RTEMS_MULTIPROCESSING)
#include <rtems/rtems/eventmp.h>
#endif
#ifndef __RTEMS_APPLICATION__
#include <rtems/rtems/event.inl>
#endif
#ifdef __cplusplus
}
#endif
#endif
/* end of include file */
|
