| /* Return frequency of ticks reported by profil. Generic version. */ |
| /*- |
| * Copyright (c) 1983, 1992, 1993 |
| * The Regents of the University of California. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 4. Neither the name of the University nor the names of its contributors |
| * may be used to endorse or promote products derived from this software |
| * without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| */ |
| |
| |
| #include <sys/types.h> |
| #include <sys/time.h> |
| #include <libc-internal.h> |
| |
| int |
| __profile_frequency (void) |
| { |
| /* |
| * Discover the tick frequency of the machine if something goes wrong, |
| * we return 0, an impossible hertz. |
| */ |
| struct itimerval tim; |
| |
| tim.it_interval.tv_sec = 0; |
| tim.it_interval.tv_usec = 1; |
| tim.it_value.tv_sec = 0; |
| tim.it_value.tv_usec = 0; |
| __setitimer(ITIMER_REAL, &tim, 0); |
| __setitimer(ITIMER_REAL, 0, &tim); |
| if (tim.it_interval.tv_usec < 2) |
| return 0; |
| return (1000000 / tim.it_interval.tv_usec); |
| } |
| libc_hidden_def (__profile_frequency) |
