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
28int 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
38int 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
48int 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
58int 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
107err:
108	set_tz(min, dst);
109	return ksft_exit_fail();
110}
111