xref: /openbsd-src/usr.bin/gprof/hertz.c (revision d13be5d47e4149db2549a9828e244d59dbc43f15)
1 /*	$OpenBSD: hertz.c,v 1.6 2006/03/25 19:06:36 espie Exp $	*/
2 
3 /*
4  * Copyright (c) 2005 Artur Grabowski <art@openbsd.org>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 
20 #include <sys/param.h>
21 #include <sys/time.h>
22 #include <sys/sysctl.h>
23 
24 #include "gprof.h"
25 
26 /*
27  * Return the tick frequency on the machine or 0 if we can't find out.
28  */
29 
30 int
31 hertz(void)
32 {
33 	struct clockinfo cinfo;
34 	int mib[2];
35 	size_t len;
36 
37 	mib[0] = CTL_KERN;
38 	mib[1] = KERN_CLOCKRATE;
39 	len = sizeof(cinfo);
40 	if (sysctl(mib, 2, &cinfo, &len, NULL, 0) == -1)
41 		return (0);
42 
43 	return (cinfo.hz);
44 }
45