xref: /linux/tools/testing/selftests/timers/set-2038.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 /* Time bounds setting test
2  *		by: john stultz (johnstul@us.ibm.com)
3  *		(C) Copyright IBM 2012
4  *		Licensed under the GPLv2
5  *
6  *  NOTE: This is a meta-test which sets the time to edge cases then
7  *  uses other tests to detect problems. Thus this test requires that
8  *  the inconsistency-check and nanosleep tests be present in the same
9  *  directory it is run from.
10  *
11  *  To build:
12  *	$ gcc set-2038.c -o set-2038 -lrt
13  *
14  *   This program is free software: you can redistribute it and/or modify
15  *   it under the terms of the GNU General Public License as published by
16  *   the Free Software Foundation, either version 2 of the License, or
17  *   (at your option) any later version.
18  *
19  *   This program is distributed in the hope that it will be useful,
20  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
21  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22  *   GNU General Public License for more details.
23  */
24 
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <unistd.h>
28 #include <time.h>
29 #include <sys/time.h>
30 #include <include/vdso/time64.h>
31 #include "../kselftest.h"
32 
33 #define KTIME_MAX	((long long)~((unsigned long long)1 << 63))
34 #define KTIME_SEC_MAX	(KTIME_MAX / NSEC_PER_SEC)
35 
36 #define YEAR_1901 (-0x7fffffffL)
37 #define YEAR_1970 1
38 #define YEAR_2038 0x7fffffffL			/*overflows 32bit time_t */
39 #define YEAR_2262 KTIME_SEC_MAX			/*overflows 64bit ktime_t */
40 #define YEAR_MAX  ((long long)((1ULL<<63)-1))	/*overflows 64bit time_t */
41 
42 int is32bits(void)
43 {
44 	return (sizeof(long) == 4);
45 }
46 
47 int settime(long long time)
48 {
49 	struct timeval now;
50 	int ret;
51 
52 	now.tv_sec = (time_t)time;
53 	now.tv_usec  = 0;
54 
55 	ret = settimeofday(&now, NULL);
56 
57 	printf("Setting time to 0x%lx: %d\n", (long)time, ret);
58 	return ret;
59 }
60 
61 int do_tests(void)
62 {
63 	int ret;
64 
65 	ret = system("date");
66 	ret = system("./inconsistency-check -c 0 -t 20");
67 	ret |= system("./nanosleep");
68 	ret |= system("./nsleep-lat");
69 	return ret;
70 
71 }
72 
73 int main(int argc, char *argv[])
74 {
75 	int ret = 0;
76 	int opt, dangerous = 0;
77 	time_t start;
78 
79 	/* Process arguments */
80 	while ((opt = getopt(argc, argv, "d")) != -1) {
81 		switch (opt) {
82 		case 'd':
83 			dangerous = 1;
84 		}
85 	}
86 
87 	start = time(0);
88 
89 	/* First test that crazy values don't work */
90 	if (!settime(YEAR_1901)) {
91 		ret = -1;
92 		goto out;
93 	}
94 	if (!settime(YEAR_MAX)) {
95 		ret = -1;
96 		goto out;
97 	}
98 	if (!is32bits() && !settime(YEAR_2262)) {
99 		ret = -1;
100 		goto out;
101 	}
102 
103 	/* Now test behavior near edges */
104 	settime(YEAR_1970);
105 	ret = do_tests();
106 	if (ret)
107 		goto out;
108 
109 	settime(YEAR_2038 - 600);
110 	ret = do_tests();
111 	if (ret)
112 		goto out;
113 
114 	/* The rest of the tests can blowup on 32bit systems */
115 	if (is32bits() && !dangerous)
116 		goto out;
117 	/* Test rollover behavior 32bit edge */
118 	settime(YEAR_2038 - 10);
119 	ret = do_tests();
120 	if (ret)
121 		goto out;
122 
123 	settime(YEAR_2262 - 600);
124 	ret = do_tests();
125 
126 out:
127 	/* restore clock */
128 	settime(start);
129 	if (ret)
130 		ksft_exit_fail();
131 	ksft_exit_pass();
132 }
133