/**
* @file
*
* @ingroup POSIXAPI
*
* @brief Suspends Execution of calling thread until Time elapses
*/
/*
* COPYRIGHT (c) 1989-2015.
* On-Line Applications Research Corporation (OAR).
*
* Copyright (c) 2016. Gedare Bloom.
*
* 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 <time.h>
#include <rtems/score/threadimpl.h>
#include <rtems/score/threadqimpl.h>
#include <rtems/score/timespec.h>
#include <rtems/score/timecounter.h>
#include <rtems/score/watchdogimpl.h>
#include <rtems/posix/posixapi.h>
static Thread_queue_Control _Nanosleep_Pseudo_queue =
THREAD_QUEUE_INITIALIZER( "Nanosleep" );
/*
* High Resolution Sleep with Specifiable Clock, IEEE Std 1003.1, 2001
*/
int clock_nanosleep(
clockid_t clock_id,
int flags,
const struct timespec *rqtp,
struct timespec *rmtp
)
{
Thread_queue_Context queue_context;
bool absolute;
Thread_Control *executing;
int eno;
if ( clock_id != CLOCK_REALTIME && clock_id != CLOCK_MONOTONIC ) {
return ENOTSUP;
}
_Thread_queue_Context_initialize( &queue_context );
_Thread_queue_Context_set_thread_state(
&queue_context,
STATES_WAITING_FOR_TIME | STATES_INTERRUPTIBLE_BY_SIGNAL
);
if ( ( flags & TIMER_ABSTIME ) != 0 ) {
absolute = true;
rmtp = NULL;
} else {
absolute = false;
}
if ( clock_id == CLOCK_REALTIME ) {
_Thread_queue_Context_set_enqueue_timeout_realtime_timespec(
&queue_context,
rqtp,
absolute
);
} else {
_Thread_queue_Context_set_enqueue_timeout_monotonic_timespec(
&queue_context,
rqtp,
absolute
);
}
_Thread_queue_Acquire( &_Nanosleep_Pseudo_queue, &queue_context );
executing = _Thread_Executing;
_Thread_queue_Enqueue(
&_Nanosleep_Pseudo_queue.Queue,
&_Thread_queue_Operations_FIFO,
executing,
&queue_context
);
eno = _POSIX_Get_error_after_wait( executing );
if ( eno == ETIMEDOUT ) {
eno = 0;
}
if ( rmtp != NULL ) {
#if defined( RTEMS_POSIX_API )
if ( eno == EINTR ) {
struct timespec actual_end;
struct timespec planned_end;
if ( clock_id == CLOCK_REALTIME ) {
_Timecounter_Nanotime( &actual_end );
} else {
_Timecounter_Nanouptime( &actual_end );
}
_Watchdog_Ticks_to_timespec(
executing->Timer.Watchdog.expire,
&planned_end
);
if ( _Timespec_Less_than( &actual_end, &planned_end ) ) {
_Timespec_Subtract( &actual_end, &planned_end, rmtp );
} else {
_Timespec_Set_to_zero( rmtp );
}
} else {
_Timespec_Set_to_zero( rmtp );
}
#else
_Assert( eno != EINTR );
_Timespec_Set_to_zero( rmtp );
#endif
}
return eno;
}