testcases/open_posix_testsuite/conformance/interfaces/clock/1-1.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 clock() returns a clock_t containing the processor time
 * since a specific point in time.
 * Dividing the return value by CLOCKS_PER_SEC gives time in seconds.
 *
 * 12/17/02 - Checking in correction made by
 *            jim.houston REMOVE-THIS AT attbi DOT com
 *            Test needed to do something as opposed to idle sleep to
 *            get the CPU time to increase.
 */
#include <time.h>
#include <stdio.h>
#include <unistd.h>
#include "posixtest.h"

#define LARGENUMBER 8000000
int main(int argc, char *argv[])
{
	clock_t c1, c2;
	double sec1, sec2;
	int i;

	c1 = clock();
	sec1 = c1/CLOCKS_PER_SEC;

	for (i = 0; i < LARGENUMBER; i++)
	{
		// keep busy so CPU time increases
		clock();
	}

	c2 = clock();
	sec2 = c2/CLOCKS_PER_SEC;

	if (sec2 > sec1) {
		printf("Times T1=%.2f, T2=%.2f\n", sec1, sec2);
		printf("Test PASSED\n");
		return PTS_PASS;
	} else {
		if (sec2 < sec1) {
			/*
		 	* probably wrapping happened; however, since
		 	* we do not know the wrap value, results are
		 	* undefined
		 	*/
			printf("TEST AGAIN:  Times probably wrapped\n");
			return PTS_UNRESOLVED;
		} else {
			printf("Error with processor times T1=%.2f, T2=%.2f\n",
					sec1, sec2);
			return PTS_FAIL;
		}
	}

	return PTS_UNRESOLVED;
}