| 1 | /* A helper tool for perl's 2038 support. |
| 2 | * See Porting/README.y2038 for details |
| 3 | */ |
| 4 | |
| 5 | #include <sys/types.h> |
| 6 | #include <stdio.h> |
| 7 | #include <time.h> |
| 8 | #include <errno.h> |
| 9 | #include <values.h> |
| 10 | |
| 11 | int opt_v = 0; |
| 12 | int i; |
| 13 | struct tm *tmp; |
| 14 | time_t pt, pt_max, pt_min; |
| 15 | |
| 16 | static char hexbuf[80]; |
| 17 | char *hex (time_t t) |
| 18 | { |
| 19 | if ((long long)t < 0) |
| 20 | sprintf (hexbuf, " -0x%016lx", -t); |
| 21 | else |
| 22 | sprintf (hexbuf, " 0x%016lx", t); |
| 23 | return (hexbuf); |
| 24 | } /* hex */ |
| 25 | |
| 26 | void gm_check (time_t t, int min_year, int max_year) |
| 27 | { |
| 28 | tmp = gmtime (&t); |
| 29 | if ( tmp == NULL || |
| 30 | /* Check tm_year overflow */ |
| 31 | tmp->tm_year < min_year || tmp->tm_year > max_year) { |
| 32 | if (opt_v) |
| 33 | fprintf (stderr, "gmtime (%ld) failed with errno %d\n", t, errno); |
| 34 | } |
| 35 | else { |
| 36 | if (opt_v) |
| 37 | fprintf (stderr, "%3d:%s: %12ld-%02d-%02d %02d:%02d:%02d\n", |
| 38 | i, hex (t), |
| 39 | tmp->tm_year + 1900, tmp->tm_mon + 1, tmp->tm_mday, |
| 40 | tmp->tm_hour, tmp->tm_min, tmp->tm_sec); |
| 41 | pt = t; |
| 42 | } |
| 43 | } /* gm_check */ |
| 44 | |
| 45 | int check_gm_max () |
| 46 | { |
| 47 | tmp = NULL; |
| 48 | pt = 0; |
| 49 | if (tmp == NULL || tmp->tm_year < 0) { |
| 50 | for (i = 63; i >= 0; i--) { |
| 51 | time_t x = pt | ((time_t)1 << i); |
| 52 | if (x < 0 || x < pt) continue; |
| 53 | gm_check (x, 69, 0x7fffffff); |
| 54 | } |
| 55 | } |
| 56 | pt_max = pt; |
| 57 | return (0); |
| 58 | } /* check_gm_max */ |
| 59 | |
| 60 | int check_gm_min () |
| 61 | { |
| 62 | tmp = NULL; |
| 63 | pt = 0; |
| 64 | if (tmp == NULL) { |
| 65 | for (i = 36; i >= 0; i--) { |
| 66 | time_t x = pt - ((time_t)1 << i); |
| 67 | if (x > 0) continue; |
| 68 | gm_check (x, -1900, 70); |
| 69 | } |
| 70 | } |
| 71 | pt_min = pt; |
| 72 | return (0); |
| 73 | } /* check_gm_min */ |
| 74 | |
| 75 | void lt_check (time_t t, int min_year, int max_year) |
| 76 | { |
| 77 | if (sizeof (time_t) > 4 && t > 0x7ffffffffffff000LL) |
| 78 | tmp = NULL; |
| 79 | else |
| 80 | tmp = localtime (&t); |
| 81 | if ( tmp == NULL || |
| 82 | /* Check tm_year overflow */ |
| 83 | tmp->tm_year < min_year || tmp->tm_year > max_year) { |
| 84 | if (opt_v) |
| 85 | fprintf (stderr, "localtime (%ld) failed with errno %d\n", t, errno); |
| 86 | } |
| 87 | else { |
| 88 | if (opt_v) |
| 89 | fprintf (stderr, "%3d:%s: %12ld-%02d-%02d %02d:%02d:%02d\n", |
| 90 | i, hex (t), |
| 91 | tmp->tm_year + 1900, tmp->tm_mon + 1, tmp->tm_mday, |
| 92 | tmp->tm_hour, tmp->tm_min, tmp->tm_sec); |
| 93 | pt = t; |
| 94 | } |
| 95 | } /* lt_check */ |
| 96 | |
| 97 | int check_lt_max () |
| 98 | { |
| 99 | tmp = NULL; |
| 100 | pt = 0; |
| 101 | if (tmp == NULL || tmp->tm_year < 0) { |
| 102 | for (i = 63; i >= 0; i--) { |
| 103 | time_t x = pt | ((time_t)1 << i); |
| 104 | if (x < 0 || x < pt) continue; |
| 105 | lt_check (x, 69, 0x7fffffff); |
| 106 | } |
| 107 | } |
| 108 | pt_max = pt; |
| 109 | return (0); |
| 110 | } /* check_lt_max */ |
| 111 | |
| 112 | int check_lt_min () |
| 113 | { |
| 114 | tmp = NULL; |
| 115 | pt = 0; |
| 116 | if (tmp == NULL) { |
| 117 | for (i = 36; i >= 0; i--) { |
| 118 | time_t x = pt - ((time_t)1 << i); |
| 119 | if (x > 0) continue; |
| 120 | lt_check (x, -1900, 70); |
| 121 | } |
| 122 | } |
| 123 | pt_min = pt; |
| 124 | return (0); |
| 125 | } /* check_lt_min */ |
| 126 | |
| 127 | int main (int argc, char *argv[]) |
| 128 | { |
| 129 | time_t gm_max, gm_min, lt_max, lt_min; |
| 130 | if (argc > 1 && strcmp (argv[1], "-v") == 0) opt_v++; |
| 131 | |
| 132 | check_gm_max (); gm_max = pt_max; |
| 133 | check_gm_min (); gm_min = pt_min; |
| 134 | check_lt_max (); lt_max = pt_max; |
| 135 | check_lt_min (); lt_min = pt_min; |
| 136 | |
| 137 | opt_v++; |
| 138 | printf ("======================\n"); |
| 139 | printf ("Sizeof time_t = %ld\n", (i = sizeof (time_t))); |
| 140 | printf ("gmtime () boundaries:\n"); |
| 141 | gm_check (gm_max, 69, 0x7fffffff); |
| 142 | gm_check (gm_min, -1900, 70); |
| 143 | printf ("localtime () boundaries:\n"); |
| 144 | lt_check (lt_max, 69, 0x7fffffff); |
| 145 | lt_check (lt_min, -1900, 70); |
| 146 | printf ("Configure variables:\n"); |
| 147 | printf ("sGMTIME_max='%ld'\n", gm_max); |
| 148 | printf ("sGMTIME_min='%ld'\n", gm_min); |
| 149 | printf ("sLOCALTIME_max='%ld'\n", lt_max); |
| 150 | printf ("sLOCALTIME_min='%ld'\n", lt_min); |
| 151 | return (0); |
| 152 | } /* main */ |