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/**
* @file
*
* @brief Core Semaphore Seize
*
* @ingroup ScoreSemaphore
*/
/*
* 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/system.h>
#include <rtems/score/isr.h>
#include <rtems/score/coresemimpl.h>
#include <rtems/score/thread.h>
#if defined(RTEMS_SCORE_CORESEM_ENABLE_SEIZE_BODY)
void _CORE_semaphore_Seize(
CORE_semaphore_Control *the_semaphore,
Thread_Control *executing,
Objects_Id id,
bool wait,
Watchdog_Interval timeout
)
{
ISR_Level level;
executing->Wait.return_code = CORE_SEMAPHORE_STATUS_SUCCESSFUL;
_ISR_Disable( level );
if ( the_semaphore->count != 0 ) {
the_semaphore->count -= 1;
_ISR_Enable( level );
return;
}
/*
* If the semaphore was not available and the caller was not willing
* to block, then return immediately with a status indicating that
* the semaphore was not available and the caller never blocked.
*/
if ( !wait ) {
_ISR_Enable( level );
executing->Wait.return_code = CORE_SEMAPHORE_STATUS_UNSATISFIED_NOWAIT;
return;
}
/*
* If the semaphore is not available and the caller is willing to
* block, then we now block the caller with optional timeout.
*/
_Thread_queue_Enter_critical_section( &the_semaphore->Wait_queue );
executing->Wait.queue = &the_semaphore->Wait_queue;
executing->Wait.id = id;
_ISR_Enable( level );
_Thread_queue_Enqueue( &the_semaphore->Wait_queue, executing, timeout );
}
#endif
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