time/tst-clock.c

   1 /* Test program for POSIX clock_* functions.
   2    Copyright (C) 2000-2020 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 2000.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <https://www.gnu.org/licenses/>.  */
  19
  20 #include <stdio.h>
  21 #include <string.h>
  22 #include <time.h>
  23 #include <stdint.h>
  24
  25
  26 /* We want to see output immediately.  */
  27 #define STDOUT_UNBUFFERED
  28
  29 static int
  30 clock_test (clockid_t cl)
  31 {
  32   struct timespec old_ts;
  33   struct timespec ts;
  34   struct timespec waitit;
  35   int result = 0;
  36   int i;
  37
  38   memset (&ts, '\0', sizeof ts);
  39
  40   waitit.tv_sec = 0;
  41   waitit.tv_nsec = 500000000;
  42
  43   /* Get and print resolution of the clock.  */
  44   if (clock_getres (cl, &ts) == 0)
  45     {
  46       if (ts.tv_nsec < 0 || ts.tv_nsec >= 1000000000)
  47         {
  48           printf ("clock %d: nanosecond value of resolution wrong\n", cl);
  49           result = 1;
  50         }
  51       else
  52         printf ("clock %d: resolution = %jd.%09jd secs\n",
  53                 cl, (intmax_t) ts.tv_sec, (intmax_t) ts.tv_nsec);
  54     }
  55   else
  56     {
  57       printf ("clock %d: cannot get resolution\n", cl);
  58       result = 1;
  59     }
  60
  61   memset (&ts, '\0', sizeof ts);
  62   memset (&old_ts, '\0', sizeof old_ts);
  63
  64   /* Next get the current time value a few times.  */
  65   for (i = 0; i < 10; ++i)
  66     {
  67       if (clock_gettime (cl, &ts) == 0)
  68         {
  69           if (ts.tv_nsec < 0 || ts.tv_nsec >= 1000000000)
  70             {
  71               printf ("clock %d: nanosecond value of time wrong (try %d)\n",
  72                       cl, i);
  73               result = 1;
  74             }
  75           else
  76             {
  77               printf ("clock %d: time = %jd.%09jd secs\n",
  78                       cl, (intmax_t) ts.tv_sec, (intmax_t) ts.tv_nsec);
  79
  80               if (memcmp (&ts, &old_ts, sizeof ts) == 0)
  81                 {
  82                   printf ("clock %d: time hasn't changed (try %d)\n", cl, i);
  83                   result = 1;
  84
  85                   old_ts = ts;
  86                 }
  87             }
  88         }
  89       else
  90         {
  91           printf ("clock %d: cannot get time (try %d)\n", cl, i);
  92           result = 1;
  93         }
  94
  95       /* Wait a bit before the next iteration.  */
  96       nanosleep (&waitit, NULL);
  97     }
  98
  99   return result;
 100 }
 101
 102 static int
 103 do_test (void)
 104 {
 105   clockid_t cl;
 106   int result;
 107
 108   result = clock_test (CLOCK_REALTIME);
 109
 110   if (clock_getcpuclockid (0, &cl) == 0)
 111     /* XXX It's not yet a bug when this fails.  */
 112     clock_test (cl);
 113   else
 114           printf("CPU clock unavailble, skipping test\n");
 115
 116   return result;
 117 }
 118 #define TEST_FUNCTION do_test ()
 119
 120
 121 #include "../test-skeleton.c"