/**
* @file
*
* @ingroup RTEMSImplClassicSemaphore
*
* @brief This source file contains the implementation of
* rtems_semaphore_obtain().
*/
/*
* COPYRIGHT (c) 1989-2014.
* 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.org/license/LICENSE.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <rtems/rtems/semimpl.h>
#include <rtems/rtems/optionsimpl.h>
#include <rtems/rtems/statusimpl.h>
THREAD_QUEUE_OBJECT_ASSERT(
Semaphore_Control,
Core_control.Wait_queue,
SEMAPHORE_CONTROL_GENERIC
);
THREAD_QUEUE_OBJECT_ASSERT(
Semaphore_Control,
Core_control.Mutex.Recursive.Mutex.Wait_queue,
SEMAPHORE_CONTROL_MUTEX
);
THREAD_QUEUE_OBJECT_ASSERT(
Semaphore_Control,
Core_control.Semaphore.Wait_queue,
SEMAPHORE_CONTROL_SEMAPHORE
);
#if defined(RTEMS_SMP)
THREAD_QUEUE_OBJECT_ASSERT(
Semaphore_Control,
Core_control.MRSP.Wait_queue,
SEMAPHORE_CONTROL_MRSP
);
#endif
rtems_status_code rtems_semaphore_obtain(
rtems_id id,
rtems_option option_set,
rtems_interval timeout
)
{
Semaphore_Control *the_semaphore;
Thread_queue_Context queue_context;
Thread_Control *executing;
bool wait;
uintptr_t flags;
Semaphore_Variant variant;
Status_Control status;
the_semaphore = _Semaphore_Get( id, &queue_context );
if ( the_semaphore == NULL ) {
#if defined(RTEMS_MULTIPROCESSING)
return _Semaphore_MP_Obtain( id, option_set, timeout );
#else
return RTEMS_INVALID_ID;
#endif
}
executing = _Thread_Executing;
wait = !_Options_Is_no_wait( option_set );
if ( wait ) {
_Thread_queue_Context_set_enqueue_timeout_ticks( &queue_context, timeout );
} else {
_Thread_queue_Context_set_enqueue_do_nothing_extra( &queue_context );
}
flags = _Semaphore_Get_flags( the_semaphore );
variant = _Semaphore_Get_variant( flags );
switch ( variant ) {
case SEMAPHORE_VARIANT_MUTEX_INHERIT_PRIORITY:
status = _CORE_recursive_mutex_Seize(
&the_semaphore->Core_control.Mutex.Recursive,
CORE_MUTEX_TQ_PRIORITY_INHERIT_OPERATIONS,
executing,
wait,
_CORE_recursive_mutex_Seize_nested,
&queue_context
);
break;
case SEMAPHORE_VARIANT_MUTEX_PRIORITY_CEILING:
status = _CORE_ceiling_mutex_Seize(
&the_semaphore->Core_control.Mutex,
executing,
wait,
_CORE_recursive_mutex_Seize_nested,
&queue_context
);
break;
case SEMAPHORE_VARIANT_MUTEX_NO_PROTOCOL:
status = _CORE_recursive_mutex_Seize(
&the_semaphore->Core_control.Mutex.Recursive,
_Semaphore_Get_operations( flags ),
executing,
wait,
_CORE_recursive_mutex_Seize_nested,
&queue_context
);
break;
#if defined(RTEMS_SMP)
case SEMAPHORE_VARIANT_MRSP:
status = _MRSP_Seize(
&the_semaphore->Core_control.MRSP,
executing,
wait,
&queue_context
);
break;
#endif
default:
_Assert(
variant == SEMAPHORE_VARIANT_SIMPLE_BINARY
|| variant == SEMAPHORE_VARIANT_COUNTING
);
status = _CORE_semaphore_Seize(
&the_semaphore->Core_control.Semaphore,
_Semaphore_Get_operations( flags ),
executing,
wait,
&queue_context
);
break;
}
return _Status_Get( status );
}