Patrick Williams | c124f4f | 2015-09-15 14:41:29 -0500 | [diff] [blame] | 1 | /* Parse dates for touch and date. |
| 2 | |
| 3 | Copyright (C) 1989, 1990, 1991, 1998, 2000, 2001, 2002, 2003, 2004, |
| 4 | 2005, 2006, 2007 Free Software Foundation Inc. |
| 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, or (at your option) |
| 9 | 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 | You should have received a copy of the GNU General Public License |
| 17 | along with this program; if not, write to the Free Software Foundation, |
| 18 | Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ |
| 19 | |
| 20 | /* Yacc-based version written by Jim Kingdon and David MacKenzie. |
| 21 | Rewritten by Jim Meyering. */ |
| 22 | |
| 23 | #include <config.h> |
| 24 | |
| 25 | #include "posixtm.h" |
| 26 | |
| 27 | #include <stdio.h> |
| 28 | #include <stdlib.h> |
| 29 | #include <sys/types.h> |
| 30 | #include <string.h> |
| 31 | |
| 32 | #if USE_UNLOCKED_IO |
| 33 | # include "unlocked-io.h" |
| 34 | #endif |
| 35 | |
| 36 | /* ISDIGIT differs from isdigit, as follows: |
| 37 | - Its arg may be any int or unsigned int; it need not be an unsigned char |
| 38 | or EOF. |
| 39 | - It's typically faster. |
| 40 | POSIX says that only '0' through '9' are digits. Prefer ISDIGIT to |
| 41 | isdigit unless it's important to use the locale's definition |
| 42 | of `digit' even when the host does not conform to POSIX. */ |
| 43 | #define ISDIGIT(c) ((unsigned int) (c) - '0' <= 9) |
| 44 | |
| 45 | time_t mktime (); |
| 46 | |
| 47 | /* |
| 48 | POSIX requires: |
| 49 | |
| 50 | touch -t [[CC]YY]mmddhhmm[.ss] FILE... |
| 51 | 8, 10, or 12 digits, followed by optional .ss |
| 52 | (PDS_LEADING_YEAR | PDS_CENTURY | PDS_SECONDS) |
| 53 | |
| 54 | touch mmddhhmm[YY] FILE... (obsoleted by POSIX 1003.1-2001) |
| 55 | 8 or 10 digits, YY (if present) must be in the range 69-99 |
| 56 | (PDS_TRAILING_YEAR | PDS_PRE_2000) |
| 57 | |
| 58 | date mmddhhmm[[CC]YY] |
| 59 | 8, 10, or 12 digits |
| 60 | (PDS_TRAILING_YEAR | PDS_CENTURY) |
| 61 | |
| 62 | */ |
| 63 | |
| 64 | static int |
| 65 | year (struct tm *tm, const int *digit_pair, size_t n, unsigned int syntax_bits) |
| 66 | { |
| 67 | switch (n) |
| 68 | { |
| 69 | case 1: |
| 70 | tm->tm_year = *digit_pair; |
| 71 | /* Deduce the century based on the year. |
| 72 | POSIX requires that 00-68 be interpreted as 2000-2068, |
| 73 | and that 69-99 be interpreted as 1969-1999. */ |
| 74 | if (digit_pair[0] <= 68) |
| 75 | { |
| 76 | if (syntax_bits & PDS_PRE_2000) |
| 77 | return 1; |
| 78 | tm->tm_year += 100; |
| 79 | } |
| 80 | break; |
| 81 | |
| 82 | case 2: |
| 83 | if (! (syntax_bits & PDS_CENTURY)) |
| 84 | return 1; |
| 85 | tm->tm_year = digit_pair[0] * 100 + digit_pair[1] - 1900; |
| 86 | break; |
| 87 | |
| 88 | case 0: |
| 89 | { |
| 90 | time_t now; |
| 91 | struct tm *tmp; |
| 92 | |
| 93 | /* Use current year. */ |
| 94 | time (&now); |
| 95 | tmp = localtime (&now); |
| 96 | if (! tmp) |
| 97 | return 1; |
| 98 | tm->tm_year = tmp->tm_year; |
| 99 | } |
| 100 | break; |
| 101 | |
| 102 | default: |
| 103 | abort (); |
| 104 | } |
| 105 | |
| 106 | return 0; |
| 107 | } |
| 108 | |
| 109 | static int |
| 110 | posix_time_parse (struct tm *tm, const char *s, unsigned int syntax_bits) |
| 111 | { |
| 112 | const char *dot = NULL; |
| 113 | int pair[6]; |
| 114 | int *p; |
| 115 | size_t i; |
| 116 | |
| 117 | size_t s_len = strlen (s); |
| 118 | size_t len = (((syntax_bits & PDS_SECONDS) && (dot = strchr (s, '.'))) |
| 119 | ? (size_t) (dot - s) |
| 120 | : s_len); |
| 121 | |
| 122 | if (len != 8 && len != 10 && len != 12) |
| 123 | return 1; |
| 124 | |
| 125 | if (dot) |
| 126 | { |
| 127 | if (!(syntax_bits & PDS_SECONDS)) |
| 128 | return 1; |
| 129 | |
| 130 | if (s_len - len != 3) |
| 131 | return 1; |
| 132 | } |
| 133 | |
| 134 | for (i = 0; i < len; i++) |
| 135 | if (!ISDIGIT (s[i])) |
| 136 | return 1; |
| 137 | |
| 138 | len /= 2; |
| 139 | for (i = 0; i < len; i++) |
| 140 | pair[i] = 10 * (s[2*i] - '0') + s[2*i + 1] - '0'; |
| 141 | |
| 142 | p = pair; |
| 143 | if (syntax_bits & PDS_LEADING_YEAR) |
| 144 | { |
| 145 | if (year (tm, p, len - 4, syntax_bits)) |
| 146 | return 1; |
| 147 | p += len - 4; |
| 148 | len = 4; |
| 149 | } |
| 150 | |
| 151 | /* Handle 8 digits worth of `MMDDhhmm'. */ |
| 152 | tm->tm_mon = *p++ - 1; |
| 153 | tm->tm_mday = *p++; |
| 154 | tm->tm_hour = *p++; |
| 155 | tm->tm_min = *p++; |
| 156 | len -= 4; |
| 157 | |
| 158 | /* Handle any trailing year. */ |
| 159 | if (syntax_bits & PDS_TRAILING_YEAR) |
| 160 | { |
| 161 | if (year (tm, p, len, syntax_bits)) |
| 162 | return 1; |
| 163 | } |
| 164 | |
| 165 | /* Handle seconds. */ |
| 166 | if (!dot) |
| 167 | { |
| 168 | tm->tm_sec = 0; |
| 169 | } |
| 170 | else |
| 171 | { |
| 172 | int seconds; |
| 173 | |
| 174 | ++dot; |
| 175 | if (!ISDIGIT (dot[0]) || !ISDIGIT (dot[1])) |
| 176 | return 1; |
| 177 | seconds = 10 * (dot[0] - '0') + dot[1] - '0'; |
| 178 | |
| 179 | tm->tm_sec = seconds; |
| 180 | } |
| 181 | |
| 182 | return 0; |
| 183 | } |
| 184 | |
| 185 | /* Parse a POSIX-style date, returning true if successful. */ |
| 186 | |
| 187 | bool |
| 188 | posixtime (time_t *p, const char *s, unsigned int syntax_bits) |
| 189 | { |
| 190 | struct tm tm0 |
| 191 | #ifdef lint |
| 192 | /* Placate gcc-4's -Wuninitialized. |
| 193 | posix_time_parse fails to set all of tm0 only when it returns |
| 194 | nonzero (due to year() returning nonzero), and in that case, |
| 195 | this code doesn't use the tm0 at all. */ |
| 196 | = { 0, } |
| 197 | #endif |
| 198 | ; |
| 199 | struct tm tm1; |
| 200 | struct tm const *tm; |
| 201 | time_t t; |
| 202 | |
| 203 | if (posix_time_parse (&tm0, s, syntax_bits)) |
| 204 | return false; |
| 205 | |
| 206 | tm1 = tm0; |
| 207 | tm1.tm_isdst = -1; |
| 208 | t = mktime (&tm1); |
| 209 | |
| 210 | if (t != (time_t) -1) |
| 211 | tm = &tm1; |
| 212 | else |
| 213 | { |
| 214 | /* mktime returns -1 for errors, but -1 is also a valid time_t |
| 215 | value. Check whether an error really occurred. */ |
| 216 | tm = localtime (&t); |
| 217 | if (! tm) |
| 218 | return false; |
| 219 | } |
| 220 | |
| 221 | /* Reject dates like "September 31" and times like "25:61". */ |
| 222 | if ((tm0.tm_year ^ tm->tm_year) |
| 223 | | (tm0.tm_mon ^ tm->tm_mon) |
| 224 | | (tm0.tm_mday ^ tm->tm_mday) |
| 225 | | (tm0.tm_hour ^ tm->tm_hour) |
| 226 | | (tm0.tm_min ^ tm->tm_min) |
| 227 | | (tm0.tm_sec ^ tm->tm_sec)) |
| 228 | return false; |
| 229 | |
| 230 | *p = t; |
| 231 | return true; |
| 232 | } |
| 233 | |
| 234 | #ifdef TEST_POSIXTIME |
| 235 | /* |
| 236 | Test mainly with syntax_bits == 13 |
| 237 | (aka: (PDS_LEADING_YEAR | PDS_CENTURY | PDS_SECONDS)) |
| 238 | |
| 239 | This test data assumes Universal Time, e.g., TZ="UTC0". |
| 240 | |
| 241 | This test data also assumes that time_t is signed and is at least |
| 242 | 39 bits wide, so that it can represent all years from 0000 through |
| 243 | 9999. A host with 32-bit signed time_t can represent only time |
| 244 | stamps in the range 1901-12-13 20:45:52 through 2038-01-18 |
| 245 | 03:14:07 UTC, assuming POSIX time_t with no leap seconds, so test |
| 246 | cases outside this range will not work on such a host. |
| 247 | |
| 248 | Also, the first two lines of test data assume that the current |
| 249 | year is 2002. |
| 250 | |
| 251 | BEGIN-DATA |
| 252 | 12131415.16 13 1039788916 Fri Dec 13 14:15:16 2002 |
| 253 | 12131415.16 13 1039788916 Fri Dec 13 14:15:16 2002 |
| 254 | 000001010000.00 13 -62167132800 Sun Jan 1 00:00:00 0000 |
| 255 | 190112132045.52 13 -2147483648 Fri Dec 13 20:45:52 1901 |
| 256 | 190112132045.53 13 -2147483647 Fri Dec 13 20:45:53 1901 |
| 257 | 190112132046.52 13 -2147483588 Fri Dec 13 20:46:52 1901 |
| 258 | 190112132145.52 13 -2147480048 Fri Dec 13 21:45:52 1901 |
| 259 | 190112142045.52 13 -2147397248 Sat Dec 14 20:45:52 1901 |
| 260 | 190201132045.52 13 -2144805248 Mon Jan 13 20:45:52 1902 |
| 261 | 196912312359.59 13 -1 Wed Dec 31 23:59:59 1969 |
| 262 | 197001010000.00 13 0 Thu Jan 1 00:00:00 1970 |
| 263 | 197001010000.01 13 1 Thu Jan 1 00:00:01 1970 |
| 264 | 197001010001.00 13 60 Thu Jan 1 00:01:00 1970 |
| 265 | 197001010100.00 13 3600 Thu Jan 1 01:00:00 1970 |
| 266 | 197001020000.00 13 86400 Fri Jan 2 00:00:00 1970 |
| 267 | 197002010000.00 13 2678400 Sun Feb 1 00:00:00 1970 |
| 268 | 197101010000.00 13 31536000 Fri Jan 1 00:00:00 1971 |
| 269 | 197001000000.00 13 * * |
| 270 | 197000010000.00 13 * * |
| 271 | 197001010000.60 13 * * |
| 272 | 197001010060.00 13 * * |
| 273 | 197001012400.00 13 * * |
| 274 | 197001320000.00 13 * * |
| 275 | 197013010000.00 13 * * |
| 276 | 203801190314.06 13 2147483646 Tue Jan 19 03:14:06 2038 |
| 277 | 203801190314.07 13 2147483647 Tue Jan 19 03:14:07 2038 |
| 278 | 203801190314.08 13 2147483648 Tue Jan 19 03:14:08 2038 |
| 279 | 999912312359.59 13 253402300799 Fri Dec 31 23:59:59 9999 |
| 280 | 1112131415 13 1323785700 Tue Dec 13 14:15:00 2011 |
| 281 | 1112131415.16 13 1323785716 Tue Dec 13 14:15:16 2011 |
| 282 | 201112131415.16 13 1323785716 Tue Dec 13 14:15:16 2011 |
| 283 | 191112131415.16 13 -1831974284 Wed Dec 13 14:15:16 1911 |
| 284 | 203712131415.16 13 2144326516 Sun Dec 13 14:15:16 2037 |
| 285 | 3712131415.16 13 2144326516 Sun Dec 13 14:15:16 2037 |
| 286 | 6812131415.16 13 3122633716 Thu Dec 13 14:15:16 2068 |
| 287 | 6912131415.16 13 -1590284 Sat Dec 13 14:15:16 1969 |
| 288 | 7012131415.16 13 29945716 Sun Dec 13 14:15:16 1970 |
| 289 | 1213141599 2 945094500 Mon Dec 13 14:15:00 1999 |
| 290 | 1213141500 2 976716900 Wed Dec 13 14:15:00 2000 |
| 291 | END-DATA |
| 292 | |
| 293 | */ |
| 294 | |
| 295 | # define MAX_BUFF_LEN 1024 |
| 296 | |
| 297 | int |
| 298 | main (void) |
| 299 | { |
| 300 | char buff[MAX_BUFF_LEN + 1]; |
| 301 | |
| 302 | buff[MAX_BUFF_LEN] = 0; |
| 303 | while (fgets (buff, MAX_BUFF_LEN, stdin) && buff[0]) |
| 304 | { |
| 305 | char time_str[MAX_BUFF_LEN]; |
| 306 | unsigned int syntax_bits; |
| 307 | time_t t; |
| 308 | if (sscanf (buff, "%s %u", time_str, &syntax_bits) != 2) |
| 309 | printf ("*\n"); |
| 310 | else |
| 311 | { |
| 312 | printf ("%-15s %2u ", time_str, syntax_bits); |
| 313 | if (posixtime (&t, time_str, syntax_bits)) |
| 314 | printf ("%12ld %s", (long int) t, ctime (&t)); |
| 315 | else |
| 316 | printf ("%12s %s", "*", "*\n"); |
| 317 | } |
| 318 | } |
| 319 | exit (0); |
| 320 | |
| 321 | } |
| 322 | #endif |
| 323 | |
| 324 | /* |
| 325 | Local Variables: |
| 326 | compile-command: "gcc -DTEST_POSIXTIME -g -O -Wall -W posixtm.c" |
| 327 | End: |
| 328 | */ |