strptime.c revision 1.42
1 /* $NetBSD: strptime.c,v 1.42 2015/07/08 19:48:20 ginsbach Exp $ */ 2 3 /*- 4 * Copyright (c) 1997, 1998, 2005, 2008 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code was contributed to The NetBSD Foundation by Klaus Klein. 8 * Heavily optimised by David Laight 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 #if defined(LIBC_SCCS) && !defined(lint) 34 __RCSID("$NetBSD: strptime.c,v 1.42 2015/07/08 19:48:20 ginsbach Exp $"); 35 #endif 36 37 #include "namespace.h" 38 #include <sys/localedef.h> 39 #include <sys/types.h> 40 #include <sys/clock.h> 41 #include <ctype.h> 42 #include <locale.h> 43 #include <string.h> 44 #include <time.h> 45 #include <tzfile.h> 46 #include "private.h" 47 #include "setlocale_local.h" 48 49 #ifdef __weak_alias 50 __weak_alias(strptime,_strptime) 51 __weak_alias(strptime_l, _strptime_l) 52 #endif 53 54 #define _TIME_LOCALE(loc) \ 55 ((_TimeLocale *)((loc)->part_impl[(size_t)LC_TIME])) 56 57 /* 58 * We do not implement alternate representations. However, we always 59 * check whether a given modifier is allowed for a certain conversion. 60 */ 61 #define ALT_E 0x01 62 #define ALT_O 0x02 63 #define LEGAL_ALT(x) { if (alt_format & ~(x)) return NULL; } 64 65 #define S_YEAR (1 << 0) 66 #define S_MON (1 << 1) 67 #define S_YDAY (1 << 2) 68 #define S_MDAY (1 << 3) 69 #define S_WDAY (1 << 4) 70 71 #define HAVE_MDAY(s) (s & S_MDAY) 72 #define HAVE_MON(s) (s & S_MON) 73 #define HAVE_WDAY(s) (s & S_WDAY) 74 #define HAVE_YDAY(s) (s & S_YDAY) 75 #define HAVE_YEAR(s) (s & S_YEAR) 76 77 static char gmt[] = { "GMT" }; 78 static char utc[] = { "UTC" }; 79 /* RFC-822/RFC-2822 */ 80 static const char * const nast[5] = { 81 "EST", "CST", "MST", "PST", "\0\0\0" 82 }; 83 static const char * const nadt[5] = { 84 "EDT", "CDT", "MDT", "PDT", "\0\0\0" 85 }; 86 87 static const u_char *conv_num(const unsigned char *, int *, uint, uint); 88 static const u_char *find_string(const u_char *, int *, const char * const *, 89 const char * const *, int); 90 91 static const int start_of_month[2][13] = { 92 { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 }, 93 { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 } 94 }; 95 96 /* 97 * Calculate the week day of the first day of a year. Valid for 98 * the Gregorian calendar, which began Sept 14, 1752 in the UK 99 * and its colonies. Ref: 100 * http://en.wikipedia.org/wiki/Determination_of_the_day_of_the_week 101 */ 102 103 static int 104 first_wday_of(int yr) 105 { 106 return ((2 * (3 - (yr / 100) % 4)) + (yr % 100) + ((yr % 100) / 4) + 107 (is_leap_year(yr) ? 6 : 0) + 1) % 7; 108 } 109 110 char * 111 strptime(const char *buf, const char *fmt, struct tm *tm) 112 { 113 return strptime_l(buf, fmt, tm, _current_locale()); 114 } 115 116 char * 117 strptime_l(const char *buf, const char *fmt, struct tm *tm, locale_t loc) 118 { 119 unsigned char c; 120 const unsigned char *bp, *ep; 121 int alt_format, i, split_year = 0, neg = 0, state = 0, 122 day_offset = -1, week_offset = 0, offs; 123 const char *new_fmt; 124 125 bp = (const u_char *)buf; 126 127 while (bp != NULL && (c = *fmt++) != '\0') { 128 /* Clear `alternate' modifier prior to new conversion. */ 129 alt_format = 0; 130 i = 0; 131 132 /* Eat up white-space. */ 133 if (isspace(c)) { 134 while (isspace(*bp)) 135 bp++; 136 continue; 137 } 138 139 if (c != '%') 140 goto literal; 141 142 143 again: switch (c = *fmt++) { 144 case '%': /* "%%" is converted to "%". */ 145 literal: 146 if (c != *bp++) 147 return NULL; 148 LEGAL_ALT(0); 149 continue; 150 151 /* 152 * "Alternative" modifiers. Just set the appropriate flag 153 * and start over again. 154 */ 155 case 'E': /* "%E?" alternative conversion modifier. */ 156 LEGAL_ALT(0); 157 alt_format |= ALT_E; 158 goto again; 159 160 case 'O': /* "%O?" alternative conversion modifier. */ 161 LEGAL_ALT(0); 162 alt_format |= ALT_O; 163 goto again; 164 165 /* 166 * "Complex" conversion rules, implemented through recursion. 167 */ 168 case 'c': /* Date and time, using the locale's format. */ 169 new_fmt = _TIME_LOCALE(loc)->d_t_fmt; 170 state |= S_WDAY | S_MON | S_MDAY | S_YEAR; 171 goto recurse; 172 173 case 'D': /* The date as "%m/%d/%y". */ 174 new_fmt = "%m/%d/%y"; 175 LEGAL_ALT(0); 176 state |= S_MON | S_MDAY | S_YEAR; 177 goto recurse; 178 179 case 'F': /* The date as "%Y-%m-%d". */ 180 new_fmt = "%Y-%m-%d"; 181 LEGAL_ALT(0); 182 state |= S_MON | S_MDAY | S_YEAR; 183 goto recurse; 184 185 case 'R': /* The time as "%H:%M". */ 186 new_fmt = "%H:%M"; 187 LEGAL_ALT(0); 188 goto recurse; 189 190 case 'r': /* The time in 12-hour clock representation. */ 191 new_fmt = _TIME_LOCALE(loc)->t_fmt_ampm; 192 LEGAL_ALT(0); 193 goto recurse; 194 195 case 'T': /* The time as "%H:%M:%S". */ 196 new_fmt = "%H:%M:%S"; 197 LEGAL_ALT(0); 198 goto recurse; 199 200 case 'X': /* The time, using the locale's format. */ 201 new_fmt = _TIME_LOCALE(loc)->t_fmt; 202 goto recurse; 203 204 case 'x': /* The date, using the locale's format. */ 205 new_fmt = _TIME_LOCALE(loc)->d_fmt; 206 state |= S_MON | S_MDAY | S_YEAR; 207 recurse: 208 bp = (const u_char *)strptime((const char *)bp, 209 new_fmt, tm); 210 LEGAL_ALT(ALT_E); 211 continue; 212 213 /* 214 * "Elementary" conversion rules. 215 */ 216 case 'A': /* The day of week, using the locale's form. */ 217 case 'a': 218 bp = find_string(bp, &tm->tm_wday, 219 _TIME_LOCALE(loc)->day, _TIME_LOCALE(loc)->abday, 7); 220 LEGAL_ALT(0); 221 state |= S_WDAY; 222 continue; 223 224 case 'B': /* The month, using the locale's form. */ 225 case 'b': 226 case 'h': 227 bp = find_string(bp, &tm->tm_mon, 228 _TIME_LOCALE(loc)->mon, _TIME_LOCALE(loc)->abmon, 229 12); 230 LEGAL_ALT(0); 231 state |= S_MON; 232 continue; 233 234 case 'C': /* The century number. */ 235 i = 20; 236 bp = conv_num(bp, &i, 0, 99); 237 238 i = i * 100 - TM_YEAR_BASE; 239 if (split_year) 240 i += tm->tm_year % 100; 241 split_year = 1; 242 tm->tm_year = i; 243 LEGAL_ALT(ALT_E); 244 state |= S_YEAR; 245 continue; 246 247 case 'd': /* The day of month. */ 248 case 'e': 249 bp = conv_num(bp, &tm->tm_mday, 1, 31); 250 LEGAL_ALT(ALT_O); 251 state |= S_MDAY; 252 continue; 253 254 case 'k': /* The hour (24-hour clock representation). */ 255 LEGAL_ALT(0); 256 /* FALLTHROUGH */ 257 case 'H': 258 bp = conv_num(bp, &tm->tm_hour, 0, 23); 259 LEGAL_ALT(ALT_O); 260 continue; 261 262 case 'l': /* The hour (12-hour clock representation). */ 263 LEGAL_ALT(0); 264 /* FALLTHROUGH */ 265 case 'I': 266 bp = conv_num(bp, &tm->tm_hour, 1, 12); 267 if (tm->tm_hour == 12) 268 tm->tm_hour = 0; 269 LEGAL_ALT(ALT_O); 270 continue; 271 272 case 'j': /* The day of year. */ 273 i = 1; 274 bp = conv_num(bp, &i, 1, 366); 275 tm->tm_yday = i - 1; 276 LEGAL_ALT(0); 277 state |= S_YDAY; 278 continue; 279 280 case 'M': /* The minute. */ 281 bp = conv_num(bp, &tm->tm_min, 0, 59); 282 LEGAL_ALT(ALT_O); 283 continue; 284 285 case 'm': /* The month. */ 286 i = 1; 287 bp = conv_num(bp, &i, 1, 12); 288 tm->tm_mon = i - 1; 289 LEGAL_ALT(ALT_O); 290 state |= S_MON; 291 continue; 292 293 case 'p': /* The locale's equivalent of AM/PM. */ 294 bp = find_string(bp, &i, _TIME_LOCALE(loc)->am_pm, 295 NULL, 2); 296 if (tm->tm_hour > 11) 297 return NULL; 298 tm->tm_hour += i * 12; 299 LEGAL_ALT(0); 300 continue; 301 302 case 'S': /* The seconds. */ 303 bp = conv_num(bp, &tm->tm_sec, 0, 61); 304 LEGAL_ALT(ALT_O); 305 continue; 306 307 #ifndef TIME_MAX 308 #define TIME_MAX INT64_MAX 309 #endif 310 case 's': /* seconds since the epoch */ 311 { 312 time_t sse = 0; 313 uint64_t rulim = TIME_MAX; 314 315 if (*bp < '0' || *bp > '9') { 316 bp = NULL; 317 continue; 318 } 319 320 do { 321 sse *= 10; 322 sse += *bp++ - '0'; 323 rulim /= 10; 324 } while ((sse * 10 <= TIME_MAX) && 325 rulim && *bp >= '0' && *bp <= '9'); 326 327 if (sse < 0 || (uint64_t)sse > TIME_MAX) { 328 bp = NULL; 329 continue; 330 } 331 332 if (localtime_r(&sse, tm) == NULL) 333 bp = NULL; 334 else 335 state |= S_YDAY | S_WDAY | 336 S_MON | S_MDAY | S_YEAR; 337 } 338 continue; 339 340 case 'U': /* The week of year, beginning on sunday. */ 341 case 'W': /* The week of year, beginning on monday. */ 342 /* 343 * XXX This is bogus, as we can not assume any valid 344 * information present in the tm structure at this 345 * point to calculate a real value, so just check the 346 * range for now. 347 */ 348 bp = conv_num(bp, &i, 0, 53); 349 LEGAL_ALT(ALT_O); 350 if (c == 'U') 351 day_offset = TM_SUNDAY; 352 else 353 day_offset = TM_MONDAY; 354 week_offset = i; 355 continue; 356 357 case 'w': /* The day of week, beginning on sunday. */ 358 bp = conv_num(bp, &tm->tm_wday, 0, 6); 359 LEGAL_ALT(ALT_O); 360 state |= S_WDAY; 361 continue; 362 363 case 'u': /* The day of week, monday = 1. */ 364 bp = conv_num(bp, &i, 1, 7); 365 tm->tm_wday = i % 7; 366 LEGAL_ALT(ALT_O); 367 continue; 368 369 case 'g': /* The year corresponding to the ISO week 370 * number but without the century. 371 */ 372 bp = conv_num(bp, &i, 0, 99); 373 continue; 374 375 case 'G': /* The year corresponding to the ISO week 376 * number with century. 377 */ 378 do 379 bp++; 380 while (isdigit(*bp)); 381 continue; 382 383 case 'V': /* The ISO 8601:1988 week number as decimal */ 384 bp = conv_num(bp, &i, 0, 53); 385 continue; 386 387 case 'Y': /* The year. */ 388 i = TM_YEAR_BASE; /* just for data sanity... */ 389 bp = conv_num(bp, &i, 0, 9999); 390 tm->tm_year = i - TM_YEAR_BASE; 391 LEGAL_ALT(ALT_E); 392 state |= S_YEAR; 393 continue; 394 395 case 'y': /* The year within 100 years of the epoch. */ 396 /* LEGAL_ALT(ALT_E | ALT_O); */ 397 bp = conv_num(bp, &i, 0, 99); 398 399 if (split_year) 400 /* preserve century */ 401 i += (tm->tm_year / 100) * 100; 402 else { 403 split_year = 1; 404 if (i <= 68) 405 i = i + 2000 - TM_YEAR_BASE; 406 else 407 i = i + 1900 - TM_YEAR_BASE; 408 } 409 tm->tm_year = i; 410 state |= S_YEAR; 411 continue; 412 413 case 'Z': 414 tzset(); 415 if (strncmp((const char *)bp, gmt, 3) == 0 || 416 strncmp((const char *)bp, utc, 3) == 0) { 417 tm->tm_isdst = 0; 418 #ifdef TM_GMTOFF 419 tm->TM_GMTOFF = 0; 420 #endif 421 #ifdef TM_ZONE 422 tm->TM_ZONE = gmt; 423 #endif 424 bp += 3; 425 } else { 426 ep = find_string(bp, &i, 427 (const char * const *)tzname, 428 NULL, 2); 429 if (ep != NULL) { 430 tm->tm_isdst = i; 431 #ifdef TM_GMTOFF 432 tm->TM_GMTOFF = -(timezone); 433 #endif 434 #ifdef TM_ZONE 435 tm->TM_ZONE = tzname[i]; 436 #endif 437 } 438 bp = ep; 439 } 440 continue; 441 442 case 'z': 443 /* 444 * We recognize all ISO 8601 formats: 445 * Z = Zulu time/UTC 446 * [+-]hhmm 447 * [+-]hh:mm 448 * [+-]hh 449 * We recognize all RFC-822/RFC-2822 formats: 450 * UT|GMT 451 * North American : UTC offsets 452 * E[DS]T = Eastern : -4 | -5 453 * C[DS]T = Central : -5 | -6 454 * M[DS]T = Mountain: -6 | -7 455 * P[DS]T = Pacific : -7 | -8 456 * Military 457 * [A-IL-M] = -1 ... -9 (J not used) 458 * [N-Y] = +1 ... +12 459 */ 460 while (isspace(*bp)) 461 bp++; 462 463 switch (*bp++) { 464 case 'G': 465 if (*bp++ != 'M') 466 return NULL; 467 /*FALLTHROUGH*/ 468 case 'U': 469 if (*bp++ != 'T') 470 return NULL; 471 /*FALLTHROUGH*/ 472 case 'Z': 473 tm->tm_isdst = 0; 474 #ifdef TM_GMTOFF 475 tm->TM_GMTOFF = 0; 476 #endif 477 #ifdef TM_ZONE 478 tm->TM_ZONE = utc; 479 #endif 480 continue; 481 case '+': 482 neg = 0; 483 state |= S_WDAY | S_MON | S_MDAY | S_YEAR; 484 break; 485 case '-': 486 neg = 1; 487 break; 488 default: 489 --bp; 490 ep = find_string(bp, &i, nast, NULL, 4); 491 if (ep != NULL) { 492 #ifdef TM_GMTOFF 493 tm->TM_GMTOFF = -5 - i; 494 #endif 495 #ifdef TM_ZONE 496 tm->TM_ZONE = __UNCONST(nast[i]); 497 #endif 498 bp = ep; 499 continue; 500 } 501 ep = find_string(bp, &i, nadt, NULL, 4); 502 if (ep != NULL) { 503 tm->tm_isdst = 1; 504 #ifdef TM_GMTOFF 505 tm->TM_GMTOFF = -4 - i; 506 #endif 507 #ifdef TM_ZONE 508 tm->TM_ZONE = __UNCONST(nadt[i]); 509 #endif 510 bp = ep; 511 continue; 512 } 513 514 if ((*bp >= 'A' && *bp <= 'I') || 515 (*bp >= 'L' && *bp <= 'Y')) { 516 #ifdef TM_GMTOFF 517 /* Argh! No 'J'! */ 518 if (*bp >= 'A' && *bp <= 'I') 519 tm->TM_GMTOFF = 520 ('A' - 1) - (int)*bp; 521 else if (*bp >= 'L' && *bp <= 'M') 522 tm->TM_GMTOFF = 'A' - (int)*bp; 523 else if (*bp >= 'N' && *bp <= 'Y') 524 tm->TM_GMTOFF = (int)*bp - 'M'; 525 #endif 526 #ifdef TM_ZONE 527 tm->TM_ZONE = NULL; /* XXX */ 528 #endif 529 bp++; 530 continue; 531 } 532 return NULL; 533 } 534 offs = 0; 535 for (i = 0; i < 4; ) { 536 if (isdigit(*bp)) { 537 offs = offs * 10 + (*bp++ - '0'); 538 i++; 539 continue; 540 } 541 if (i == 2 && *bp == ':') { 542 bp++; 543 continue; 544 } 545 break; 546 } 547 switch (i) { 548 case 2: 549 offs *= 100; 550 break; 551 case 4: 552 i = offs % 100; 553 if (i >= 60) 554 return NULL; 555 /* Convert minutes into decimal */ 556 offs = (offs / 100) * 100 + (i * 50) / 30; 557 break; 558 default: 559 return NULL; 560 } 561 if (neg) 562 offs = -offs; 563 tm->tm_isdst = 0; /* XXX */ 564 #ifdef TM_GMTOFF 565 tm->TM_GMTOFF = offs; 566 #endif 567 #ifdef TM_ZONE 568 tm->TM_ZONE = NULL; /* XXX */ 569 #endif 570 continue; 571 572 /* 573 * Miscellaneous conversions. 574 */ 575 case 'n': /* Any kind of white-space. */ 576 case 't': 577 while (isspace(*bp)) 578 bp++; 579 LEGAL_ALT(0); 580 continue; 581 582 583 default: /* Unknown/unsupported conversion. */ 584 return NULL; 585 } 586 } 587 588 if (!HAVE_YDAY(state) && HAVE_YEAR(state)) { 589 if (HAVE_MON(state) && HAVE_MDAY(state)) { 590 tm->tm_yday = start_of_month[is_leap_year(tm->tm_year + 591 TM_YEAR_BASE)][tm->tm_mon] + (tm->tm_mday - 1); 592 state |= S_YDAY; 593 } else if (day_offset != -1) { 594 /* Set the date to the first Sunday (or Monday) 595 * of the specified week of the year. 596 */ 597 if (!HAVE_WDAY(state)) { 598 tm->tm_wday = day_offset; 599 state |= S_WDAY; 600 } 601 tm->tm_yday = (7 - 602 first_wday_of(tm->tm_year + TM_YEAR_BASE) + 603 day_offset) % 7 + (week_offset - 1) * 7 + 604 tm->tm_wday - day_offset; 605 state |= S_YDAY; 606 } 607 } 608 609 if (HAVE_YDAY(state) && HAVE_YEAR(state)) { 610 int isleap; 611 if (!HAVE_MON(state)) { 612 i = 0; 613 isleap = is_leap_year(tm->tm_year + TM_YEAR_BASE); 614 while (tm->tm_yday >= start_of_month[isleap][i]) 615 i++; 616 if (i > 12) { 617 i = 1; 618 tm->tm_yday -= start_of_month[isleap][12]; 619 tm->tm_year++; 620 } 621 tm->tm_mon = i - 1; 622 state |= S_MON; 623 } 624 if (!HAVE_MDAY(state)) { 625 isleap = is_leap_year(tm->tm_year + TM_YEAR_BASE); 626 tm->tm_mday = tm->tm_yday - 627 start_of_month[isleap][tm->tm_mon] + 1; 628 state |= S_MDAY; 629 } 630 if (!HAVE_WDAY(state)) { 631 i = 0; 632 week_offset = first_wday_of(tm->tm_year); 633 while (i++ <= tm->tm_yday) { 634 if (week_offset++ >= 6) 635 week_offset = 0; 636 } 637 tm->tm_wday = week_offset; 638 state |= S_WDAY; 639 } 640 } 641 642 return __UNCONST(bp); 643 } 644 645 646 static const u_char * 647 conv_num(const unsigned char *buf, int *dest, uint llim, uint ulim) 648 { 649 uint result = 0; 650 unsigned char ch; 651 652 /* The limit also determines the number of valid digits. */ 653 uint rulim = ulim; 654 655 ch = *buf; 656 if (ch < '0' || ch > '9') 657 return NULL; 658 659 do { 660 result *= 10; 661 result += ch - '0'; 662 rulim /= 10; 663 ch = *++buf; 664 } while ((result * 10 <= ulim) && rulim && ch >= '0' && ch <= '9'); 665 666 if (result < llim || result > ulim) 667 return NULL; 668 669 *dest = result; 670 return buf; 671 } 672 673 static const u_char * 674 find_string(const u_char *bp, int *tgt, const char * const *n1, 675 const char * const *n2, int c) 676 { 677 int i; 678 size_t len; 679 680 /* check full name - then abbreviated ones */ 681 for (; n1 != NULL; n1 = n2, n2 = NULL) { 682 for (i = 0; i < c; i++, n1++) { 683 len = strlen(*n1); 684 if (strncasecmp(*n1, (const char *)bp, len) == 0) { 685 *tgt = i; 686 return bp + len; 687 } 688 } 689 } 690 691 /* Nothing matched */ 692 return NULL; 693 } 694
Indexes created Fri Sep 26 08:10:20 GMT 2025