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 "../kselftest.h"
31 
32 #define NSEC_PER_SEC 1000000000LL
33 
34 #define KTIME_MAX	((long long)~((unsigned long long)1 << 63))
35 #define KTIME_SEC_MAX	(KTIME_MAX / NSEC_PER_SEC)
36 
37 #define YEAR_1901 (-0x7fffffffL)
38 #define YEAR_1970 1
39 #define YEAR_2038 0x7fffffffL			/*overflows 32bit time_t */
40 #define YEAR_2262 KTIME_SEC_MAX			/*overflows 64bit ktime_t */
41 #define YEAR_MAX  ((long long)((1ULL<<63)-1))	/*overflows 64bit time_t */
42 
is32bits(void)43 int is32bits(void)
44 {
45 	return (sizeof(long) == 4);
46 }
47 
settime(long long time)48 int settime(long long time)
49 {
50 	struct timeval now;
51 	int ret;
52 
53 	now.tv_sec = (time_t)time;
54 	now.tv_usec  = 0;
55 
56 	ret = settimeofday(&now, NULL);
57 
58 	printf("Setting time to 0x%lx: %d\n", (long)time, ret);
59 	return ret;
60 }
61 
do_tests(void)62 int do_tests(void)
63 {
64 	int ret;
65 
66 	ret = system("date");
67 	ret = system("./inconsistency-check -c 0 -t 20");
68 	ret |= system("./nanosleep");
69 	ret |= system("./nsleep-lat");
70 	return ret;
71 
72 }
73 
main(int argc,char * argv[])74 int main(int argc, char *argv[])
75 {
76 	int ret = 0;
77 	int opt, dangerous = 0;
78 	time_t start;
79 
80 	/* Process arguments */
81 	while ((opt = getopt(argc, argv, "d")) != -1) {
82 		switch (opt) {
83 		case 'd':
84 			dangerous = 1;
85 		}
86 	}
87 
88 	start = time(0);
89 
90 	/* First test that crazy values don't work */
91 	if (!settime(YEAR_1901)) {
92 		ret = -1;
93 		goto out;
94 	}
95 	if (!settime(YEAR_MAX)) {
96 		ret = -1;
97 		goto out;
98 	}
99 	if (!is32bits() && !settime(YEAR_2262)) {
100 		ret = -1;
101 		goto out;
102 	}
103 
104 	/* Now test behavior near edges */
105 	settime(YEAR_1970);
106 	ret = do_tests();
107 	if (ret)
108 		goto out;
109 
110 	settime(YEAR_2038 - 600);
111 	ret = do_tests();
112 	if (ret)
113 		goto out;
114 
115 	/* The rest of the tests can blowup on 32bit systems */
116 	if (is32bits() && !dangerous)
117 		goto out;
118 	/* Test rollover behavior 32bit edge */
119 	settime(YEAR_2038 - 10);
120 	ret = do_tests();
121 	if (ret)
122 		goto out;
123 
124 	settime(YEAR_2262 - 600);
125 	ret = do_tests();
126 
127 out:
128 	/* restore clock */
129 	settime(start);
130 	if (ret)
131 		return ksft_exit_fail();
132 	return ksft_exit_pass();
133 }
134