1/*
2 * Copyright (c) 1983, 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#include "gprof.h"
30#include "hertz.h"
31
32
33int
34hertz (void)
35{
36#ifdef HERTZ
37  return HERTZ;
38#else /* ! defined (HERTZ) */
39#ifdef HAVE_SETITIMER
40  struct itimerval tim;
41
42  tim.it_interval.tv_sec = 0;
43  tim.it_interval.tv_usec = 1;
44  tim.it_value.tv_sec = 0;
45  tim.it_value.tv_usec = 0;
46  setitimer (ITIMER_REAL, &tim, 0);
47  setitimer (ITIMER_REAL, 0, &tim);
48  if (tim.it_interval.tv_usec >= 2)
49    {
50      return 1000000 / tim.it_interval.tv_usec;
51    }
52#endif /* ! defined (HAVE_SETITIMER) */
53#if defined (HAVE_SYSCONF) && defined (_SC_CLK_TCK)
54  return sysconf (_SC_CLK_TCK);
55#else /* ! defined (HAVE_SYSCONF) || ! defined (_SC_CLK_TCK) */
56#ifdef __MSDOS__
57  return 18;
58#else  /* ! defined (__MSDOS__) */
59  return HZ_WRONG;
60#endif /* ! defined (__MSDOS__) */
61#endif /* ! defined (HAVE_SYSCONF) || ! defined (_SC_CLK_TCK) */
62#endif /* ! defined (HERTZ) */
63}
64