time/tst-clock.c

   1 /* Test program for POSIX clock_* functions.
   2    Copyright (C) 2000-2024 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C 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 GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <stdio.h>
  20 #include <string.h>
  21 #include <time.h>
  22 #include <stdint.h>
  23
  24
  25 /* We want to see output immediately.  */
  26 #define STDOUT_UNBUFFERED
  27
  28 static int
  29 clock_test (clockid_t cl)
  30 {
  31   struct timespec old_ts;
  32   struct timespec ts;
  33   struct timespec waitit;
  34   int result = 0;
  35   int i;
  36
  37   memset (&ts, '\0', sizeof ts);
  38
  39   waitit.tv_sec = 0;
  40   waitit.tv_nsec = 500000000;
  41
  42   /* Get and print resolution of the clock.  */
  43   if (clock_getres (cl, &ts) == 0)
  44     {
  45       if (ts.tv_nsec < 0 || ts.tv_nsec >= 1000000000)
  46         {
  47           printf ("clock %d: nanosecond value of resolution wrong\n", cl);
  48           result = 1;
  49         }
  50       else
  51         printf ("clock %d: resolution = %jd.%09jd secs\n",
  52                 cl, (intmax_t) ts.tv_sec, (intmax_t) ts.tv_nsec);
  53     }
  54   else
  55     {
  56       printf ("clock %d: cannot get resolution\n", cl);
  57       result = 1;
  58     }
  59
  60   memset (&ts, '\0', sizeof ts);
  61   memset (&old_ts, '\0', sizeof old_ts);
  62
  63   /* Next get the current time value a few times.  */
  64   for (i = 0; i < 10; ++i)
  65     {
  66       if (clock_gettime (cl, &ts) == 0)
  67         {
  68           if (ts.tv_nsec < 0 || ts.tv_nsec >= 1000000000)
  69             {
  70               printf ("clock %d: nanosecond value of time wrong (try %d)\n",
  71                       cl, i);
  72               result = 1;
  73             }
  74           else
  75             {
  76               printf ("clock %d: time = %jd.%09jd secs\n",
  77                       cl, (intmax_t) ts.tv_sec, (intmax_t) ts.tv_nsec);
  78
  79               if (memcmp (&ts, &old_ts, sizeof ts) == 0)
  80                 {
  81                   printf ("clock %d: time hasn't changed (try %d)\n", cl, i);
  82                   result = 1;
  83
  84                   old_ts = ts;
  85                 }
  86             }
  87         }
  88       else
  89         {
  90           printf ("clock %d: cannot get time (try %d)\n", cl, i);
  91           result = 1;
  92         }
  93
  94       /* Wait a bit before the next iteration.  */
  95       nanosleep (&waitit, NULL);
  96     }
  97
  98   return result;
  99 }
 100
 101 static int
 102 do_test (void)
 103 {
 104   clockid_t cl;
 105   int result;
 106
 107   result = clock_test (CLOCK_REALTIME);
 108
 109   if (clock_getcpuclockid (0, &cl) == 0)
 110     /* XXX It's not yet a bug when this fails.  */
 111     clock_test (cl);
 112   else
 113           printf("CPU clock unavailable, skipping test\n");
 114
 115   return result;
 116 }
 117 #define TEST_FUNCTION do_test ()
 118
 119
 120 #include "../test-skeleton.c"