testcases/open_posix_testsuite/conformance/interfaces/timer_gettime/1-3.c

/*
 * Copyright (c) 2002, Intel Corporation. All rights reserved.
 * Created by:  julie.n.fleischer REMOVE-THIS AT intel DOT com
 * This file is licensed under the GPL license.  For the full content
 * of this license, see the COPYING file at the top level of this
 * source tree.

 * Test that timer_gettime() sets sets itimerspec.it_value to the
 * amount of time remaining in the middle of a timer.
 * - Create and arm a timer for TIMERNSEC nanoseconds.
 * - Sleep for SLEEPNSEC < TIMERNSEC.
 * - Call timer_gettime().
 * - Ensure the value returned is within ACCEPTABLEDELTA less than
 *   TIMERNSEC-SLEEPNSEC.
 *
 * Signal SIGCONT will be used so that it will not affect the test if
 * the timer expires.
 * Clock CLOCK_REALTIME will be used.
 */

#include <time.h>
#include <signal.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include "posixtest.h"

#define TIMERNSEC 800000000
#define SLEEPNSEC 400000000
#define ACCEPTABLEDELTA 30000000

int main(int argc, char *argv[])
{
	struct sigevent ev;
	timer_t tid;
	struct itimerspec itsset, itsget;
	struct timespec ts;
	int deltans;

	ev.sigev_notify = SIGEV_SIGNAL;
	ev.sigev_signo = SIGCONT;

	itsset.it_interval.tv_sec = 0;
	itsset.it_interval.tv_nsec = 0;
	itsset.it_value.tv_sec = 0;
	itsset.it_value.tv_nsec = TIMERNSEC;

	if (timer_create(CLOCK_REALTIME, &ev, &tid)) {
		perror("timer_create()");
		return PTS_UNRESOLVED;
	}

	if (timer_settime(tid, 0, &itsset, NULL)) {
		perror("timer_settime()");
		return PTS_UNRESOLVED;
	}

	ts.tv_sec = 0;
	ts.tv_nsec = SLEEPNSEC;
	if (nanosleep(&ts, NULL)) {
		perror("nanosleep()");
		return PTS_UNRESOLVED;
	}

	if (timer_gettime(tid, &itsget)) {
		perror("timer_gettime()");
		return PTS_UNRESOLVED;
	}

	/*
	 * Algorithm for determining success:
	 * - itsget must be < itsset
	 * - itsset-itsget nsec must be <= ACCEPTABLEDELTA
	 */

	if (itsget.it_value.tv_sec) {
		printf("FAIL:  timer_gettime tv_sec: %lu seconds > 0 seconds\n",
			itsget.it_value.tv_sec);
		return PTS_FAIL;
	}

	deltans = (itsset.it_value.tv_nsec - ts.tv_nsec) -
					itsget.it_value.tv_nsec;

	if (deltans < 0 || deltans > ACCEPTABLEDELTA) {
		printf("FAIL:  timer_gettime() deltans: %d allowed: %u\n",
			deltans, ACCEPTABLEDELTA);
		return PTS_FAIL;
	}

	printf("Test PASSED\n");
	return PTS_PASS;
}