1 /* Set tz value 2 * by: John Stultz <john.stultz (at) 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 #ifdef KTEST 27 #include "../kselftest.h" 28 #else 29 static inline int ksft_exit_pass(void) 30 { 31 exit(0); 32 } 33 static inline int ksft_exit_fail(void) 34 { 35 exit(1); 36 } 37 #endif 38 39 int set_tz(int min, int dst) 40 { 41 struct timezone tz; 42 43 tz.tz_minuteswest = min; 44 tz.tz_dsttime = dst; 45 46 return settimeofday(0, &tz); 47 } 48 49 int get_tz_min(void) 50 { 51 struct timezone tz; 52 struct timeval tv; 53 54 memset(&tz, 0, sizeof(tz)); 55 gettimeofday(&tv, &tz); 56 return tz.tz_minuteswest; 57 } 58 59 int get_tz_dst(void) 60 { 61 struct timezone tz; 62 struct timeval tv; 63 64 memset(&tz, 0, sizeof(tz)); 65 gettimeofday(&tv, &tz); 66 return tz.tz_dsttime; 67 } 68 69 int main(int argc, char **argv) 70 { 71 int i, ret; 72 int min, dst; 73 74 min = get_tz_min(); 75 dst = get_tz_dst(); 76 printf("tz_minuteswest started at %i, dst at %i\n", min, dst); 77 78 printf("Checking tz_minuteswest can be properly set: "); 79 for (i = -15*60; i < 15*60; i += 30) { 80 ret = set_tz(i, dst); 81 ret = get_tz_min(); 82 if (ret != i) { 83 printf("[FAILED] expected: %i got %i\n", i, ret); 84 goto err; 85 } 86 } 87 printf("[OK]\n"); 88 89 printf("Checking invalid tz_minuteswest values are caught: "); 90 91 if (!set_tz(-15*60-1, dst)) { 92 printf("[FAILED] %i didn't return failure!\n", -15*60-1); 93 goto err; 94 } 95 96 if (!set_tz(15*60+1, dst)) { 97 printf("[FAILED] %i didn't return failure!\n", 15*60+1); 98 goto err; 99 } 100 101 if (!set_tz(-24*60, dst)) { 102 printf("[FAILED] %i didn't return failure!\n", -24*60); 103 goto err; 104 } 105 106 if (!set_tz(24*60, dst)) { 107 printf("[FAILED] %i didn't return failure!\n", 24*60); 108 goto err; 109 } 110 111 printf("[OK]\n"); 112 113 set_tz(min, dst); 114 return ksft_exit_pass(); 115 116 err: 117 set_tz(min, dst); 118 return ksft_exit_fail(); 119 } 120
