LXR linux/tools/testing/selftests/timers/set-2038.c

   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#ifdef KTEST
  31#include "../kselftest.h"
  32#else
  33static inline int ksft_exit_pass(void)
  34{
  35        exit(0);
  36}
  37static inline int ksft_exit_fail(void)
  38{
  39        exit(1);
  40}
  41#endif
  42
  43#define NSEC_PER_SEC 1000000000LL
  44
  45#define KTIME_MAX       ((long long)~((unsigned long long)1 << 63))
  46#define KTIME_SEC_MAX   (KTIME_MAX / NSEC_PER_SEC)
  47
  48#define YEAR_1901 (-0x7fffffffL)
  49#define YEAR_1970 1
  50#define YEAR_2038 0x7fffffffL                   /*overflows 32bit time_t */
  51#define YEAR_2262 KTIME_SEC_MAX                 /*overflows 64bit ktime_t */
  52#define YEAR_MAX  ((long long)((1ULL<<63)-1))   /*overflows 64bit time_t */
  53
  54int is32bits(void)
  55{
  56        return (sizeof(long) == 4);
  57}
  58
  59int settime(long long time)
  60{
  61        struct timeval now;
  62        int ret;
  63
  64        now.tv_sec = (time_t)time;
  65        now.tv_usec  = 0;
  66
  67        ret = settimeofday(&now, NULL);
  68
  69        printf("Setting time to 0x%lx: %d\n", (long)time, ret);
  70        return ret;
  71}
  72
  73int do_tests(void)
  74{
  75        int ret;
  76
  77        ret = system("date");
  78        ret = system("./inconsistency-check -c 0 -t 20");
  79        ret |= system("./nanosleep");
  80        ret |= system("./nsleep-lat");
  81        return ret;
  82
  83}
  84
  85int main(int argc, char *argv[])
  86{
  87        int ret = 0;
  88        int opt, dangerous = 0;
  89        time_t start;
  90
  91        /* Process arguments */
  92        while ((opt = getopt(argc, argv, "d")) != -1) {
  93                switch (opt) {
  94                case 'd':
  95                        dangerous = 1;
  96                }
  97        }
  98
  99        start = time(0);
 100
 101        /* First test that crazy values don't work */
 102        if (!settime(YEAR_1901)) {
 103                ret = -1;
 104                goto out;
 105        }
 106        if (!settime(YEAR_MAX)) {
 107                ret = -1;
 108                goto out;
 109        }
 110        if (!is32bits() && !settime(YEAR_2262)) {
 111                ret = -1;
 112                goto out;
 113        }
 114
 115        /* Now test behavior near edges */
 116        settime(YEAR_1970);
 117        ret = do_tests();
 118        if (ret)
 119                goto out;
 120
 121        settime(YEAR_2038 - 600);
 122        ret = do_tests();
 123        if (ret)
 124                goto out;
 125
 126        /* The rest of the tests can blowup on 32bit systems */
 127        if (is32bits() && !dangerous)
 128                goto out;
 129        /* Test rollover behavior 32bit edge */
 130        settime(YEAR_2038 - 10);
 131        ret = do_tests();
 132        if (ret)
 133                goto out;
 134
 135        settime(YEAR_2262 - 600);
 136        ret = do_tests();
 137
 138out:
 139        /* restore clock */
 140        settime(start);
 141        if (ret)
 142                return ksft_exit_fail();
 143        return ksft_exit_pass();
 144}
 145