libc/gen/clock.c

1.1  cgd /*
1.1  cgd  * Copyright (c) 1989 The Regents of the University of California.
1.1  cgd  * All rights reserved.
1.1  cgd  *
1.1  cgd  * Redistribution and use in source and binary forms, with or without
1.1  cgd  * modification, are permitted provided that the following conditions
1.1  cgd  * are met:
1.1  cgd  * 1. Redistributions of source code must retain the above copyright
1.1  cgd  *    notice, this list of conditions and the following disclaimer.
1.1  cgd  * 2. Redistributions in binary form must reproduce the above copyright
1.1  cgd  *    notice, this list of conditions and the following disclaimer in the
1.1  cgd  *    documentation and/or other materials provided with the distribution.
1.1  cgd  * 3. All advertising materials mentioning features or use of this software
1.1  cgd  *    must display the following acknowledgement:
1.1  cgd  *	This product includes software developed by the University of
1.1  cgd  *	California, Berkeley and its contributors.
1.1  cgd  * 4. Neither the name of the University nor the names of its contributors
1.1  cgd  *    may be used to endorse or promote products derived from this software
1.1  cgd  *    without specific prior written permission.
1.1  cgd  *
1.1  cgd  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
1.1  cgd  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
1.1  cgd  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
1.1  cgd  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
1.1  cgd  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
1.1  cgd  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
1.1  cgd  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
1.1  cgd  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
1.1  cgd  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
1.1  cgd  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
1.1  cgd  * SUCH DAMAGE.
1.1  cgd  */
1.1  cgd
1.1  cgd #if defined(LIBC_SCCS) && !defined(lint)
1.1  cgd static char sccsid[] = "@(#)clock.c	5.4 (Berkeley) 8/27/90";
1.1  cgd #endif /* LIBC_SCCS and not lint */
1.1  cgd
1.1  cgd #include <sys/param.h>
1.1  cgd #include <sys/time.h>
1.1  cgd #include <sys/resource.h>
1.1  cgd
1.1  cgd /*
1.1  cgd  * Convert usec to clock ticks; could do (usec * CLK_TCK) / 1000000,
1.1  cgd  * but this would overflow if we switch to nanosec.
1.1  cgd  */
1.1  cgd #define	CONVTCK(r)	(r.tv_sec * CLK_TCK + r.tv_usec / (1000000 / CLK_TCK))
1.1  cgd
1.1  cgd clock_t
1.1  cgd clock()
1.1  cgd {
1.1  cgd 	struct rusage ru;
1.1  cgd
1.1  cgd 	if (getrusage(RUSAGE_SELF, &ru))
1.1  cgd 		return ((clock_t) -1);
1.1  cgd 	return((clock_t)((CONVTCK(ru.ru_utime) + CONVTCK(ru.ru_stime))));
1.1  cgd }