xref: /freebsd/lib/libc/gen/times.c (revision 076ad2f8)
1 /*-
2  * Copyright (c) 1990, 1993
3  *	The Regents of the University of California.  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. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #if defined(LIBC_SCCS) && !defined(lint)
31 static char sccsid[] = "@(#)times.c	8.1 (Berkeley) 6/4/93";
32 #endif /* LIBC_SCCS and not lint */
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/param.h>
37 #include <sys/time.h>
38 #include <sys/times.h>
39 #include <sys/resource.h>
40 
41 /*
42  * Convert usec to clock ticks; could do (usec * CLK_TCK) / 1000000,
43  * but this would overflow if we switch to nanosec.
44  */
45 #define	CONVTCK(r)	(r.tv_sec * CLK_TCK + r.tv_usec / (1000000 / CLK_TCK))
46 
47 clock_t
48 times(tp)
49 	struct tms *tp;
50 {
51 	struct rusage ru;
52 	struct timespec t;
53 	clock_t c;
54 
55 	if (getrusage(RUSAGE_SELF, &ru) < 0)
56 		return ((clock_t)-1);
57 	tp->tms_utime = CONVTCK(ru.ru_utime);
58 	tp->tms_stime = CONVTCK(ru.ru_stime);
59 	if (getrusage(RUSAGE_CHILDREN, &ru) < 0)
60 		return ((clock_t)-1);
61 	tp->tms_cutime = CONVTCK(ru.ru_utime);
62 	tp->tms_cstime = CONVTCK(ru.ru_stime);
63 	if (clock_gettime(CLOCK_MONOTONIC, &t))
64 		return ((clock_t)-1);
65 	c = t.tv_sec * CLK_TCK + t.tv_nsec / (1000000000 / CLK_TCK);
66 	return (c);
67 }
68