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/**
* @file
*
* @brief Event Manager Initialization
* @ingroup ClassicEvent Events
*/
/*
* COPYRIGHT (c) 1989-2008.
* 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.
*/
#if HAVE_CONFIG_H
#include "config.h"
#endif
#include <rtems/rtems/eventimpl.h>
#include <rtems/rtems/optionsimpl.h>
#include <rtems/score/threadimpl.h>
#include <rtems/score/watchdogimpl.h>
/*
* INTERRUPT LATENCY:
* available
* wait
* check sync
*/
void _Event_Seize(
rtems_event_set event_in,
rtems_option option_set,
rtems_interval ticks,
rtems_event_set *event_out,
Thread_Control *executing,
Event_Control *event,
Thread_blocking_operation_States *sync_state,
States_Control wait_state
)
{
rtems_event_set seized_events;
rtems_event_set pending_events;
ISR_Level level;
Thread_blocking_operation_States current_sync_state;
executing->Wait.return_code = RTEMS_SUCCESSFUL;
_ISR_Disable( level );
pending_events = event->pending_events;
seized_events = _Event_sets_Get( pending_events, event_in );
if ( !_Event_sets_Is_empty( seized_events ) &&
(seized_events == event_in || _Options_Is_any( option_set )) ) {
event->pending_events =
_Event_sets_Clear( pending_events, seized_events );
_ISR_Enable( level );
*event_out = seized_events;
return;
}
if ( _Options_Is_no_wait( option_set ) ) {
_ISR_Enable( level );
executing->Wait.return_code = RTEMS_UNSATISFIED;
*event_out = seized_events;
return;
}
/*
* Note what we are waiting for BEFORE we enter the critical section.
* The interrupt critical section management code needs this to be
* set properly when we are marked as in the event critical section.
*
* NOTE: Since interrupts are disabled, this isn't that much of an
* issue but better safe than sorry.
*/
executing->Wait.option = option_set;
executing->Wait.count = event_in;
executing->Wait.return_argument = event_out;
*sync_state = THREAD_BLOCKING_OPERATION_NOTHING_HAPPENED;
_ISR_Enable( level );
if ( ticks ) {
_Watchdog_Initialize(
&executing->Timer,
_Event_Timeout,
executing->Object.id,
sync_state
);
_Watchdog_Insert_ticks( &executing->Timer, ticks );
}
_Thread_Set_state( executing, wait_state );
_ISR_Disable( level );
current_sync_state = *sync_state;
*sync_state = THREAD_BLOCKING_OPERATION_SYNCHRONIZED;
if ( current_sync_state == THREAD_BLOCKING_OPERATION_NOTHING_HAPPENED ) {
_ISR_Enable( level );
return;
}
/*
* An interrupt completed the thread's blocking request.
* The blocking thread was satisfied by an ISR or timed out.
*
* WARNING! Entering with interrupts disabled and returning with interrupts
* enabled!
*/
_Thread_blocking_operation_Cancel( current_sync_state, executing, level );
}
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