tools/testing/selftests/timers/set-tz.c

   1 /* Set tz value
   2  *              by: John Stultz <john.stultz@linaro.org>
   3  *              (C) Copyright Linaro 2016
   4  *              Licensed under the GPLv2
   5  *
   6  *   This program is free software: you can redistribute it and/or modify
   7  *   it under the terms of the GNU General Public License as published by
   8  *   the Free Software Foundation, either version 2 of the License, or
   9  *   (at your option) any later version.
  10  *
  11  *   This program 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
  14  *   GNU General Public License for more details.
  15  */
  16
  17
  18 #include <stdio.h>
  19 #include <stdlib.h>
  20 #include <time.h>
  21 #include <sys/time.h>
  22 #include <sys/timex.h>
  23 #include <string.h>
  24 #include <signal.h>
  25 #include <unistd.h>
  26 #include "../kselftest.h"
  27
  28 int set_tz(int min, int dst)
  29 {
  30         struct timezone tz;
  31
  32         tz.tz_minuteswest = min;
  33         tz.tz_dsttime = dst;
  34
  35         return settimeofday(0, &tz);
  36 }
  37
  38 int get_tz_min(void)
  39 {
  40         struct timezone tz;
  41         struct timeval tv;
  42
  43         memset(&tz, 0, sizeof(tz));
  44         gettimeofday(&tv, &tz);
  45         return tz.tz_minuteswest;
  46 }
  47
  48 int get_tz_dst(void)
  49 {
  50         struct timezone tz;
  51         struct timeval tv;
  52
  53         memset(&tz, 0, sizeof(tz));
  54         gettimeofday(&tv, &tz);
  55         return tz.tz_dsttime;
  56 }
  57
  58 int main(int argc, char **argv)
  59 {
  60         int i, ret;
  61         int min, dst;
  62
  63         min = get_tz_min();
  64         dst = get_tz_dst();
  65         printf("tz_minuteswest started at %i, dst at %i\n", min, dst);
  66
  67         printf("Checking tz_minuteswest can be properly set: ");
  68         fflush(stdout);
  69         for (i = -15*60; i < 15*60; i += 30) {
  70                 ret = set_tz(i, dst);
  71                 ret = get_tz_min();
  72                 if (ret != i) {
  73                         printf("[FAILED] expected: %i got %i\n", i, ret);
  74                         goto err;
  75                 }
  76         }
  77         printf("[OK]\n");
  78
  79         printf("Checking invalid tz_minuteswest values are caught: ");
  80         fflush(stdout);
  81
  82         if (!set_tz(-15*60-1, dst)) {
  83                 printf("[FAILED] %i didn't return failure!\n", -15*60-1);
  84                 goto err;
  85         }
  86
  87         if (!set_tz(15*60+1, dst)) {
  88                 printf("[FAILED] %i didn't return failure!\n", 15*60+1);
  89                 goto err;
  90         }
  91
  92         if (!set_tz(-24*60, dst)) {
  93                 printf("[FAILED] %i didn't return failure!\n", -24*60);
  94                 goto err;
  95         }
  96
  97         if (!set_tz(24*60, dst)) {
  98                 printf("[FAILED] %i didn't return failure!\n", 24*60);
  99                 goto err;
 100         }
 101
 102         printf("[OK]\n");
 103
 104         set_tz(min, dst);
 105         return ksft_exit_pass();
 106
 107 err:
 108         set_tz(min, dst);
 109         return ksft_exit_fail();
 110 }