xref: /freebsd/lib/libc/gen/times.c (revision a64729f5077d77e13b9497cb33ecb3c82e606ee8)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1990, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/param.h>
33 #include <sys/time.h>
34 #include <sys/times.h>
35 #include <sys/resource.h>
36 
37 /*
38  * Convert usec to clock ticks; could do (usec * CLK_TCK) / 1000000,
39  * but this would overflow if we switch to nanosec.
40  */
41 #define	CONVTCK(r)	(r.tv_sec * CLK_TCK + r.tv_usec / (1000000 / CLK_TCK))
42 
43 clock_t
44 times(struct tms *tp)
45 {
46 	struct rusage ru;
47 	struct timespec t;
48 	clock_t c;
49 
50 	if (getrusage(RUSAGE_SELF, &ru) < 0)
51 		return ((clock_t)-1);
52 	tp->tms_utime = CONVTCK(ru.ru_utime);
53 	tp->tms_stime = CONVTCK(ru.ru_stime);
54 	if (getrusage(RUSAGE_CHILDREN, &ru) < 0)
55 		return ((clock_t)-1);
56 	tp->tms_cutime = CONVTCK(ru.ru_utime);
57 	tp->tms_cstime = CONVTCK(ru.ru_stime);
58 	if (clock_gettime(CLOCK_MONOTONIC, &t))
59 		return ((clock_t)-1);
60 	c = t.tv_sec * CLK_TCK + t.tv_nsec / (1000000000 / CLK_TCK);
61 	return (c);
62 }
63