libiberty/clock.c

   1 /* ANSI-compatible clock function.
   2    Copyright (C) 1994-2017 Free Software Foundation, Inc.
   3
   4 This file is part of the libiberty library.  This library is free
   5 software; you can redistribute it and/or modify it under the
   6 terms of the GNU General Public License as published by the
   7 Free Software Foundation; either version 2, or (at your option)
   8 any later version.
   9
  10 This library is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with GNU CC; see the file COPYING.  If not, write to
  17 the Free Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.
  18
  19 As a special exception, if you link this library with files
  20 compiled with a GNU compiler to produce an executable, this does not cause
  21 the resulting executable to be covered by the GNU General Public License.
  22 This exception does not however invalidate any other reasons why
  23 the executable file might be covered by the GNU General Public License. */
  24
  25 /*
  26
  27 @deftypefn Supplemental long clock (void)
  28
  29 Returns an approximation of the CPU time used by the process as a
  30 @code{clock_t}; divide this number by @samp{CLOCKS_PER_SEC} to get the
  31 number of seconds used.
  32
  33 @end deftypefn
  34
  35 */
  36
  37 #include "config.h"
  38
  39 #ifdef HAVE_GETRUSAGE
  40 #include <sys/time.h>
  41 #include <sys/resource.h>
  42 #endif
  43
  44 #ifdef HAVE_TIMES
  45 #ifdef HAVE_SYS_PARAM_H
  46 #include <sys/param.h>
  47 #endif
  48 #include <sys/times.h>
  49 #endif
  50
  51 #ifdef HAVE_UNISTD_H
  52 #include <unistd.h>
  53 #endif
  54
  55 #ifdef _SC_CLK_TCK
  56 #define GNU_HZ  sysconf(_SC_CLK_TCK)
  57 #else
  58 #ifdef HZ
  59 #define GNU_HZ  HZ
  60 #else
  61 #ifdef CLOCKS_PER_SEC
  62 #define GNU_HZ  CLOCKS_PER_SEC
  63 #endif
  64 #endif
  65 #endif
  66
  67 /* FIXME: should be able to declare as clock_t. */
  68
  69 long
  70 clock (void)
  71 {
  72 #ifdef HAVE_GETRUSAGE
  73   struct rusage rusage;
  74
  75   getrusage (0, &rusage);
  76   return (rusage.ru_utime.tv_sec * 1000000 + rusage.ru_utime.tv_usec
  77           + rusage.ru_stime.tv_sec * 1000000 + rusage.ru_stime.tv_usec);
  78 #else
  79 #ifdef HAVE_TIMES
  80   struct tms tms;
  81
  82   times (&tms);
  83   return (tms.tms_utime + tms.tms_stime) * (1000000 / GNU_HZ);
  84 #else
  85 #ifdef VMS
  86   struct
  87     {
  88       int proc_user_time;
  89       int proc_system_time;
  90       int child_user_time;
  91       int child_system_time;
  92     } vms_times;
  93
  94   times (&vms_times);
  95   return (vms_times.proc_user_time + vms_times.proc_system_time) * 10000;
  96 #else
  97   /* A fallback, if nothing else available. */
  98   return 0;
  99 #endif /* VMS */
 100 #endif /* HAVE_TIMES */
 101 #endif /* HAVE_GETRUSAGE */
 102 }
 103