/* SPDX-License-Identifier: BSD-2-Clause */
/**
* @file
*
* @ingroup POSIXAPI
*
* @brief Function Returns the Resolution of any Clock
*/
/*
* COPYRIGHT (c) 1989-2007.
* On-Line Applications Research Corporation (OAR).
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <time.h>
#include <errno.h>
#include <rtems/score/todimpl.h>
#include <rtems/config.h>
#include <rtems/seterr.h>
/*
* 14.2.1 Clocks, P1003.1b-1993, p. 263
*/
int clock_getres(
clockid_t clock_id,
struct timespec *res
)
{
if ( !res )
rtems_set_errno_and_return_minus_one( EINVAL );
switch ( clock_id ) {
/*
* All time in rtems is based on the same clock tick.
*/
case CLOCK_REALTIME:
case CLOCK_PROCESS_CPUTIME_ID:
case CLOCK_THREAD_CPUTIME_ID:
if ( res ) {
res->tv_sec = rtems_configuration_get_microseconds_per_tick() /
TOD_MICROSECONDS_PER_SECOND;
res->tv_nsec = rtems_configuration_get_nanoseconds_per_tick();
}
break;
default:
rtems_set_errno_and_return_minus_one( EINVAL );
}
return 0;
}
