Home | History | Annotate | Line # | Download | only in gen
clock.c revision 1.4.4.1 
      1 /*
      2  * Copyright (c) 1989 The Regents of the University of California.
      3  * All rights reserved.
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that the following conditions
      7  * are met:
      8  * 1. Redistributions of source code must retain the above copyright
      9  *    notice, this list of conditions and the following disclaimer.
     10  * 2. Redistributions in binary form must reproduce the above copyright
     11  *    notice, this list of conditions and the following disclaimer in the
     12  *    documentation and/or other materials provided with the distribution.
     13  * 3. All advertising materials mentioning features or use of this software
     14  *    must display the following acknowledgement:
     15  *	This product includes software developed by the University of
     16  *	California, Berkeley and its contributors.
     17  * 4. Neither the name of the University nor the names of its contributors
     18  *    may be used to endorse or promote products derived from this software
     19  *    without specific prior written permission.
     20  *
     21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     31  * SUCH DAMAGE.
     32  */
     33 
     34 #if defined(LIBC_SCCS) && !defined(lint)
     35 /*static char *sccsid = "from: @(#)clock.c	5.4 (Berkeley) 8/27/90";*/
     36 static char *rcsid = "$Id: clock.c,v 1.4.4.1 1995/04/26 00:17:52 jtc Exp $";
     37 #endif /* LIBC_SCCS and not lint */
     38 
     39 #include "namespace.h"
     40 #include <sys/param.h>
     41 #include <sys/time.h>
     42 #include <sys/resource.h>
     43 
     44 /*
     45  * Convert usec to clock ticks; could do (usec * CLOCKS_PER_SEC) / 1000000,
     46  * but this would overflow if we switch to nanosec.
     47  */
     48 #define	CONVTCK(r)	(r.tv_sec * CLOCKS_PER_SEC + \
     49 			 r.tv_usec / (1000000 / CLOCKS_PER_SEC))
     50 
     51 clock_t
     52 clock()
     53 {
     54 	struct rusage ru;
     55 
     56 	if (getrusage(RUSAGE_SELF, &ru))
     57 		return ((clock_t) -1);
     58 	return((clock_t)((CONVTCK(ru.ru_utime) + CONVTCK(ru.ru_stime))));
     59 }
     60