tests/test-localtime_r-mt.c

   1 /* Multithread-safety test for localtime_r().
   2    Copyright (C) 2024-2025 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Bruno Haible <bruno@clisp.org>, 2024.  */
  18
  19 #include <config.h>
  20
  21 /* Work around GCC bug 44511.  */
  22 #if _GL_GNUC_PREREQ (4, 3)
  23 # pragma GCC diagnostic ignored "-Wreturn-type"
  24 #endif
  25
  26 #if USE_ISOC_THREADS || USE_POSIX_THREADS || USE_ISOC_AND_POSIX_THREADS || USE_WINDOWS_THREADS
  27
  28 /* Specification.  */
  29 #include <time.h>
  30
  31 #include <stdio.h>
  32 #include <stdlib.h>
  33
  34 #include "glthread/thread.h"
  35 #include "macros.h"
  36
  37
  38 /* Some common time zone name.  */
  39
  40 #if defined _WIN32 && !defined __CYGWIN__
  41 /* Cf. <https://learn.microsoft.com/en-us/windows-hardware/manufacture/desktop/default-time-zones>
  42    or <https://ss64.com/timezones.html>  */
  43 # define FRENCH_TZ  "Romance Standard Time"
  44 #else
  45 /* Cf. <https://en.wikipedia.org/wiki/List_of_tz_database_time_zones>  */
  46 # define FRENCH_TZ  "Europe/Paris"
  47 #endif
  48
  49
  50 static void *
  51 thread1_func (void *arg)
  52 {
  53   for (;;)
  54     {
  55
  56       time_t t = 1178467200; /* 2007-05-06 18:00:00 */
  57       struct tm tm;
  58       struct tm *result = localtime_r (&t, &tm);
  59       ASSERT (result == &tm);
  60       if (!(result->tm_sec == 0
  61             && result->tm_min == 0
  62             && result->tm_hour == 18
  63             && result->tm_mday == 6
  64             && result->tm_mon == 5 - 1
  65             && result->tm_year == 2007 - 1900
  66             && result->tm_wday == 0
  67             && result->tm_yday == 125
  68             && result->tm_isdst == 1))
  69         {
  70           fprintf (stderr, "thread1 disturbed by thread2!\n"); fflush (stderr);
  71           abort ();
  72         }
  73     }
  74
  75   /*NOTREACHED*/
  76 }
  77
  78 static void *
  79 thread2_func (void *arg)
  80 {
  81   for (;;)
  82     {
  83       time_t t = 1336320000; /* 2012-05-06 18:00:00 */
  84       struct tm tm;
  85       struct tm *result = localtime_r (&t, &tm);
  86       ASSERT (result == &tm);
  87       if (!(result->tm_sec == 0
  88             && result->tm_min == 0
  89             && result->tm_hour == 18
  90             && result->tm_mday == 6
  91             && result->tm_mon == 5 - 1
  92             && result->tm_year == 2012 - 1900
  93             && result->tm_wday == 0
  94             && result->tm_yday == 126
  95             && result->tm_isdst == 1))
  96         {
  97           fprintf (stderr, "thread2 disturbed by thread1!\n"); fflush (stderr);
  98           abort ();
  99         }
 100     }
 101
 102   /*NOTREACHED*/
 103 }
 104
 105 int
 106 main (int argc, char *argv[])
 107 {
 108   setenv ("TZ", FRENCH_TZ, 1);
 109
 110   /* Check that this TZ works.  */
 111   {
 112     time_t t = 0; /* 1970-01-01 01:00:00 */
 113     struct tm *result = localtime (&t);
 114     if (! (result
 115            && result->tm_sec == 0
 116            && result->tm_min == 0
 117            && result->tm_hour == 1
 118            && result->tm_mday == 1
 119            && result->tm_mon == 1 - 1
 120            && result->tm_year == 1970 - 1900
 121            && result->tm_wday == 4
 122            && result->tm_yday == 0
 123            && result->tm_isdst == 0))
 124       {
 125         fputs ("Skipping test: TZ='" FRENCH_TZ "' is not Paris time\n",
 126                stderr);
 127         return 77;
 128       }
 129   }
 130
 131   /* Create the threads.  */
 132   gl_thread_create (thread1_func, NULL);
 133   gl_thread_create (thread2_func, NULL);
 134
 135   /* Let them run for 1 second.  */
 136   {
 137     struct timespec duration;
 138     duration.tv_sec = (argc > 1 ? atoi (argv[1]) : 1);
 139     duration.tv_nsec = 0;
 140
 141     nanosleep (&duration, NULL);
 142   }
 143
 144   return test_exit_status;
 145 }
 146
 147 #else
 148
 149 /* No multithreading available.  */
 150
 151 #include <stdio.h>
 152
 153 int
 154 main ()
 155 {
 156   fputs ("Skipping test: multithreading not enabled\n", stderr);
 157   return 77;
 158 }
 159
 160 #endif