1/* 2 * parsetime.c - parse time for at(1) 3 * Copyright (C) 1993, 1994 Thomas Koenig 4 * 5 * modifications for English-language times 6 * Copyright (C) 1993 David Parsons 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. The name of the author(s) may not be used to endorse or promote 14 * products derived from this software without specific prior written 15 * permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 * 28 * at [NOW] PLUS NUMBER MINUTES|HOURS|DAYS|WEEKS 29 * DOT ::= ':'|'.' 30 * /NUMBER [DOT NUMBER] [AM|PM]\ /[MONTH NUMBER [NUMBER]] \ 31 * |NOON | |[TOMORROW] | 32 * |MIDNIGHT | |[DAY OF WEEK] | 33 * \TEATIME / |NUMBER [SLASH NUMBER [SLASH NUMBER]]| 34 * \PLUS NUMBER MINUTES|HOURS|DAYS|WEEKS/ 35 */ 36 37#include <sys/cdefs.h> 38__FBSDID("$FreeBSD: /usr/local/www/cvsroot/FreeBSD/src/usr.bin/at/parsetime.c,v 1.28 2011/11/06 17:32:29 ed Exp $"); 39 40/* System Headers */ 41 42#include <sys/types.h> 43#include <ctype.h> 44#include <err.h> 45#include <errno.h> 46#include <stdio.h> 47#include <stdlib.h> 48#include <string.h> 49#include <time.h> 50#include <tzfile.h> 51#include <unistd.h> 52#ifndef __FreeBSD__ 53#include <getopt.h> 54#endif 55 56/* Local headers */ 57 58#include "at.h" 59#include "panic.h" 60#include "parsetime.h" 61 62 63/* Structures and unions */ 64 65enum { /* symbols */ 66 MIDNIGHT, NOON, TEATIME, 67 PM, AM, TOMORROW, TODAY, NOW, 68 MINUTES, HOURS, DAYS, WEEKS, MONTHS, YEARS, 69 NUMBER, PLUS, DOT, COMMA, SLASH, ID, JUNK, 70 JAN, FEB, MAR, APR, MAY, JUN, 71 JUL, AUG, SEP, OCT, NOV, DEC, 72 SUN, MON, TUE, WED, THU, FRI, SAT, 73 UTC, NEXT 74 }; 75 76/* parse translation table - table driven parsers can be your FRIEND! 77 */ 78static const struct { 79 const char *name; /* token name */ 80 int value; /* token id */ 81 int plural; /* is this plural? */ 82} Specials[] = { 83 { "midnight", MIDNIGHT,0 }, /* 00:00:00 of today or tomorrow */ 84 { "noon", NOON,0 }, /* 12:00:00 of today or tomorrow */ 85 { "teatime", TEATIME,0 }, /* 16:00:00 of today or tomorrow */ 86 { "am", AM,0 }, /* morning times for 0-12 clock */ 87 { "pm", PM,0 }, /* evening times for 0-12 clock */ 88 { "tomorrow", TOMORROW,0 }, /* execute 24 hours from time */ 89 { "today", TODAY, 0 }, /* execute today - don't advance time */ 90 { "now", NOW,0 }, /* opt prefix for PLUS */ 91 92 { "minute", MINUTES,0 }, /* minutes multiplier */ 93 { "minutes", MINUTES,1 }, /* (pluralized) */ 94 { "hour", HOURS,0 }, /* hours ... */ 95 { "hours", HOURS,1 }, /* (pluralized) */ 96 { "day", DAYS,0 }, /* days ... */ 97 { "days", DAYS,1 }, /* (pluralized) */ 98 { "week", WEEKS,0 }, /* week ... */ 99 { "weeks", WEEKS,1 }, /* (pluralized) */ 100 { "month", MONTHS,0 }, /* month ... */ 101 { "months", MONTHS,1 }, /* (pluralized) */ 102 { "year", YEARS,0 }, /* year ... */ 103 { "years", YEARS,1 }, /* (pluralized) */ 104 { "jan", JAN,0 }, 105 { "feb", FEB,0 }, 106 { "mar", MAR,0 }, 107 { "apr", APR,0 }, 108 { "may", MAY,0 }, 109 { "jun", JUN,0 }, 110 { "jul", JUL,0 }, 111 { "aug", AUG,0 }, 112 { "sep", SEP,0 }, 113 { "oct", OCT,0 }, 114 { "nov", NOV,0 }, 115 { "dec", DEC,0 }, 116 { "january", JAN,0 }, 117 { "february", FEB,0 }, 118 { "march", MAR,0 }, 119 { "april", APR,0 }, 120 { "may", MAY,0 }, 121 { "june", JUN,0 }, 122 { "july", JUL,0 }, 123 { "august", AUG,0 }, 124 { "september", SEP,0 }, 125 { "october", OCT,0 }, 126 { "november", NOV,0 }, 127 { "december", DEC,0 }, 128 { "sunday", SUN, 0 }, 129 { "sun", SUN, 0 }, 130 { "monday", MON, 0 }, 131 { "mon", MON, 0 }, 132 { "tuesday", TUE, 0 }, 133 { "tue", TUE, 0 }, 134 { "wednesday", WED, 0 }, 135 { "wed", WED, 0 }, 136 { "thursday", THU, 0 }, 137 { "thu", THU, 0 }, 138 { "friday", FRI, 0 }, 139 { "fri", FRI, 0 }, 140 { "saturday", SAT, 0 }, 141 { "sat", SAT, 0 }, 142 { "utc", UTC, 0 }, 143 { "next", NEXT, 0 }, 144} ; 145 146/* File scope variables */ 147 148static char **scp; /* scanner - pointer at arglist */ 149static char scc; /* scanner - count of remaining arguments */ 150static char *sct; /* scanner - next char pointer in current argument */ 151static int need; /* scanner - need to advance to next argument */ 152 153static char *sc_token; /* scanner - token buffer */ 154static size_t sc_len; /* scanner - length of token buffer */ 155static int sc_tokid; /* scanner - token id */ 156static int sc_tokplur; /* scanner - is token plural? */ 157 158/* Local functions */ 159 160/* 161 * parse a token, checking if it's something special to us 162 */ 163static int 164parse_token(char *arg) 165{ 166 size_t i; 167 168 for (i=0; i<(sizeof Specials/sizeof Specials[0]); i++) 169 if (strcasecmp(Specials[i].name, arg) == 0) { 170 sc_tokplur = Specials[i].plural; 171 return sc_tokid = Specials[i].value; 172 } 173 174 /* not special - must be some random id */ 175 return sc_tokid = ID; 176} /* parse_token */ 177 178 179/* 180 * init_scanner() sets up the scanner to eat arguments 181 */ 182static void 183init_scanner(int argc, char **argv) 184{ 185 scp = argv; 186 scc = argc; 187 need = 1; 188 sc_len = 1; 189 while (argc-- > 0) 190 sc_len += strlen(*argv++); 191 192 if ((sc_token = malloc(sc_len)) == NULL) 193 errx(EXIT_FAILURE, "virtual memory exhausted"); 194} /* init_scanner */ 195 196/* 197 * token() fetches a token from the input stream 198 */ 199static int 200token(void) 201{ 202 int idx; 203 204 while (1) { 205 memset(sc_token, 0, sc_len); 206 sc_tokid = EOF; 207 sc_tokplur = 0; 208 idx = 0; 209 210 /* if we need to read another argument, walk along the argument list; 211 * when we fall off the arglist, we'll just return EOF forever 212 */ 213 if (need) { 214 if (scc < 1) 215 return sc_tokid; 216 sct = *scp; 217 scp++; 218 scc--; 219 need = 0; 220 } 221 /* eat whitespace now - if we walk off the end of the argument, 222 * we'll continue, which puts us up at the top of the while loop 223 * to fetch the next argument in 224 */ 225 while (isspace(*sct)) 226 ++sct; 227 if (!*sct) { 228 need = 1; 229 continue; 230 } 231 232 /* preserve the first character of the new token 233 */ 234 sc_token[0] = *sct++; 235 236 /* then see what it is 237 */ 238 if (isdigit(sc_token[0])) { 239 while (isdigit(*sct)) 240 sc_token[++idx] = *sct++; 241 sc_token[++idx] = 0; 242 return sc_tokid = NUMBER; 243 } 244 else if (isalpha(sc_token[0])) { 245 while (isalpha(*sct)) 246 sc_token[++idx] = *sct++; 247 sc_token[++idx] = 0; 248 return parse_token(sc_token); 249 } 250 else if (sc_token[0] == ':' || sc_token[0] == '.') 251 return sc_tokid = DOT; 252 else if (sc_token[0] == '+') 253 return sc_tokid = PLUS; 254 else if (sc_token[0] == '/') 255 return sc_tokid = SLASH; 256 else if (sc_token[0] == ',') 257 return sc_tokid = COMMA; 258 else 259 return sc_tokid = JUNK; 260 } /* while (1) */ 261} /* token */ 262 263 264/* 265 * plonk() gives an appropriate error message if a token is incorrect 266 */ 267static void 268plonk(int tok) 269{ 270 panic((tok == EOF) ? "incomplete time" 271 : "garbled time"); 272} /* plonk */ 273 274 275/* 276 * expect() gets a token and dies most horribly if it's not the token we want 277 */ 278static void 279expect(int desired) 280{ 281 if (token() != desired) 282 plonk(sc_tokid); /* and we die here... */ 283} /* expect */ 284 285 286/* 287 * plus() parses a now + time 288 * 289 * at [NOW] PLUS NUMBER [MINUTES|HOURS|DAYS|WEEKS|MONTHS|YEARS] 290 * 291 */ 292 293static void 294plus(struct tm *tm) 295{ 296 int delay; 297 int expectplur; 298 299 expect(NUMBER); 300 301 delay = atoi(sc_token); 302 expectplur = (delay != 1) ? 1 : 0; 303 304 switch (token()) { 305 case YEARS: 306 tm->tm_year += delay; 307 break; 308 case MONTHS: 309 tm->tm_mon += delay; 310 break; 311 case WEEKS: 312 delay *= 7; 313 case DAYS: 314 tm->tm_mday += delay; 315 break; 316 case HOURS: 317 tm->tm_hour += delay; 318 break; 319 case MINUTES: 320 tm->tm_min += delay; 321 break; 322 default: 323 plonk(sc_tokid); 324 break; 325 } 326 327 if (expectplur != sc_tokplur) 328 warnx("pluralization is wrong"); 329 330 tm->tm_isdst = -1; 331 if (mktime(tm) < 0) 332 plonk(sc_tokid); 333 334} /* plus */ 335 336/* 337 * at [NOW] NEXT [MINUTES|HOURS|DAYS|WEEKS|MONTHS|YEARS] 338 */ 339static void 340next(struct tm *tm) 341{ 342 switch (token()) { 343 case YEARS: 344 tm->tm_year++; 345 break; 346 347 case MONTHS: 348 tm->tm_mon++; 349 break; 350 351 case WEEKS: 352 tm->tm_mday += 7; 353 break; 354 355 case DAYS: 356 tm->tm_mday++; 357 break; 358 359 case HOURS: 360 tm->tm_hour++; 361 break; 362 363 case MINUTES: 364 tm->tm_min++; 365 break; 366 367 default: 368 plonk(sc_tokid); 369 break; 370 } 371 372 if (sc_tokplur) { 373 warnx("pluralization is wrong"); 374 } 375 tm->tm_isdst = -1; 376 if (mktime(tm) < 0) { 377 plonk(sc_tokid); 378 } 379} /* next */ 380 381/* 382 * tod() computes the time of day 383 * [NUMBER [DOT NUMBER] [AM|PM]] [UTC] 384 */ 385static void 386tod(struct tm *tm) 387{ 388 int hour, minute = 0; 389 size_t tlen; 390 391 hour = atoi(sc_token); 392 tlen = strlen(sc_token); 393 394 /* first pick out the time of day - if it's 4 digits, we assume 395 * a HHMM time, otherwise it's HH DOT MM time 396 */ 397 if (token() == DOT) { 398 expect(NUMBER); 399 minute = atoi(sc_token); 400 if (minute > 59) 401 panic("garbled time"); 402 token(); 403 } 404 else if (tlen == 4) { 405 minute = hour%100; 406 if (minute > 59) 407 panic("garbled time"); 408 hour = hour/100; 409 } 410 411 /* check if an AM or PM specifier was given 412 */ 413 switch (sc_tokid) { 414 case AM: 415 case PM: 416 if (hour > 12) 417 panic("garbled time"); 418 419 if (sc_tokid == PM) { 420 if (hour != 12) /* 12:xx PM is 12:xx, not 24:xx */ 421 hour += 12; 422 } else { 423 if (hour == 12) /* 12:xx AM is 00:xx, not 12:xx */ 424 hour = 0; 425 } 426 if (UTC != token()) 427 break; /* else fallthrough */ 428 429 case UTC: 430 hour += tm->tm_gmtoff/(60*60); 431 while (hour < 0) 432 hour += 24; 433 minute += (tm->tm_gmtoff/60); 434 while (minute < 0) 435 minute += 60; 436 tm->tm_gmtoff = 0; 437 token(); 438 break; 439 default: 440 if (hour > 23) 441 panic("garbled time"); 442 break; 443 } 444 445 /* if we specify an absolute time, we don't want to bump the day even 446 * if we've gone past that time - but if we're specifying a time plus 447 * a relative offset, it's okay to bump things 448 * If minutes are the same assume tomorrow was meant 449 */ 450 if ((sc_tokid == EOF || sc_tokid == PLUS) && 451 ((tm->tm_hour > hour) || ((tm->tm_hour == hour) && (tm->tm_min >= minute)))) { 452 tm->tm_mday++; 453 tm->tm_wday++; 454 } 455 456 tm->tm_hour = hour; 457 tm->tm_min = minute; 458 if (tm->tm_hour == 24) { 459 tm->tm_hour = 0; 460 tm->tm_mday++; 461 } 462} /* tod */ 463 464 465/* 466 * assign_date() assigns a date, wrapping to next year if needed 467 */ 468static void 469assign_date(struct tm *tm, int mday, int mon, int year) 470{ 471 /* 472 * Convert year into tm_year format (year - 1900). 473 * We may be given the year in 2 digit, 4 digit, or tm_year format. 474 */ 475 if (year != -1) { 476 if (year >= TM_YEAR_BASE) 477 year -= TM_YEAR_BASE; /* convert from 4 digit year */ 478 else if (year < 100) { 479 /* convert from 2 digit year */ 480 struct tm *lt; 481 time_t now; 482 483 time(&now); 484 lt = localtime(&now); 485 486 /* Convert to tm_year assuming current century */ 487 year += (lt->tm_year / 100) * 100; 488 489 if (year == lt->tm_year - 1) year++; 490 else if (year < lt->tm_year) 491 year += 100; /* must be in next century */ 492 } 493 } 494 495 if (year < 0 && 496 (tm->tm_mon > mon ||(tm->tm_mon == mon && tm->tm_mday > mday))) 497 year = tm->tm_year + 1; 498 499 tm->tm_mday = mday; 500 tm->tm_mon = mon; 501 502 if (year >= 0) 503 tm->tm_year = year; 504} /* assign_date */ 505 506 507/* 508 * month() picks apart a month specification 509 * 510 * /[<month> NUMBER [NUMBER]] \ 511 * |[TOMORROW] | 512 * |[DAY OF WEEK] | 513 * |NUMBER [SLASH NUMBER [SLASH NUMBER]]| 514 * |NEXT MINUTES|HOURS|DAYS|WEEKS|MONTHS|YEARS| 515 * \PLUS NUMBER MINUTES|HOURS|DAYS|WEEKS/ 516 */ 517static void 518month(struct tm *tm) 519{ 520 int year= (-1); 521 int mday = 0, wday, mon; 522 int tlen; 523 524 switch (sc_tokid) { 525 case PLUS: 526 plus(tm); 527 break; 528 529 case NEXT: 530 next(tm); 531 break; 532 533 case TOMORROW: 534 /* do something tomorrow */ 535 tm->tm_mday ++; 536 tm->tm_wday ++; 537 case TODAY: /* force ourselves to stay in today - no further processing */ 538 token(); 539 break; 540 541 case JAN: case FEB: case MAR: case APR: case MAY: case JUN: 542 case JUL: case AUG: case SEP: case OCT: case NOV: case DEC: 543 /* do month mday [,year] 544 */ 545 mon = (sc_tokid-JAN); 546 expect(NUMBER); 547 mday = atoi(sc_token); 548 if (token() == COMMA) { 549 if (token() == NUMBER) { 550 year = atoi(sc_token); 551 token(); 552 } 553 } 554 assign_date(tm, mday, mon, year); 555 if (sc_tokid == PLUS) 556 plus(tm); 557 break; 558 559 case SUN: case MON: case TUE: 560 case WED: case THU: case FRI: 561 case SAT: 562 /* do a particular day of the week 563 */ 564 wday = (sc_tokid-SUN); 565 566 mday = tm->tm_mday; 567 568 /* if this day is < today, then roll to next week 569 */ 570 if (wday < tm->tm_wday) 571 mday += 7 - (tm->tm_wday - wday); 572 else 573 mday += (wday - tm->tm_wday); 574 575 tm->tm_wday = wday; 576 577 assign_date(tm, mday, tm->tm_mon, tm->tm_year); 578 break; 579 580 case NUMBER: 581 /* get numeric MMDDYY, mm/dd/yy, or dd.mm.yy 582 */ 583 tlen = (int)strlen(sc_token); 584 mon = atoi(sc_token); 585 token(); 586 587 if (sc_tokid == SLASH || sc_tokid == DOT) { 588 int sep; 589 590 sep = sc_tokid; 591 expect(NUMBER); 592 mday = atoi(sc_token); 593 if (token() == sep) { 594 expect(NUMBER); 595 year = atoi(sc_token); 596 token(); 597 } 598 599 /* flip months and days for European timing 600 */ 601 if (sep == DOT) { 602 int x = mday; 603 mday = mon; 604 mon = x; 605 } 606 } 607 else if (tlen == 6 || tlen == 8) { 608 if (tlen == 8) { 609 year = (mon % 10000) - TM_YEAR_BASE; 610 mon /= 10000; 611 } 612 else { 613 year = mon % 100; 614 mon /= 100; 615 } 616 mday = mon % 100; 617 mon /= 100; 618 } 619 else 620 panic("garbled time"); 621 622 mon--; 623 if (mon < 0 || mon > 11 || mday < 1 || mday > 31) 624 panic("garbled time"); 625 626 assign_date(tm, mday, mon, year); 627 break; 628 629 case EOF: 630 break; 631 632 default: 633 plonk(sc_tokid); 634 break; 635 } /* case */ 636} /* month */ 637 638 639/* Global functions */ 640 641time_t 642parsetime(int argc, char **argv) 643{ 644 /* Do the argument parsing, die if necessary, and return the time the job 645 * should be run. 646 */ 647 time_t nowtimer, runtimer; 648 struct tm nowtime, runtime; 649 int hr = 0; 650 /* this MUST be initialized to zero for midnight/noon/teatime */ 651 652 nowtimer = time(NULL); 653 nowtime = *localtime(&nowtimer); 654 655 runtime = nowtime; 656 runtime.tm_sec = 0; 657 runtime.tm_isdst = 0; 658 659 if (argc <= optind) 660 usage(); 661 662 init_scanner(argc-optind, argv+optind); 663 664 switch (token()) { 665 case NOW: 666 if (scc < 1) { 667 return nowtimer; 668 } 669 /* now is optional prefix for PLUS/NEXT tree */ 670 switch (token()) { 671 case PLUS: 672 plus(&runtime); 673 break; 674 675 case NEXT: 676 next(&runtime); 677 break; 678 679 default: 680 plonk(sc_token); 681 break; 682 } 683 break; 684 685 case PLUS: 686 plus(&runtime); 687 break; 688 689 case NEXT: 690 next(&runtime); 691 break; 692 693 case NUMBER: 694 tod(&runtime); 695 month(&runtime); 696 break; 697 698 /* evil coding for TEATIME|NOON|MIDNIGHT - we've initialised 699 * hr to zero up above, then fall into this case in such a 700 * way so we add +12 +4 hours to it for teatime, +12 hours 701 * to it for noon, and nothing at all for midnight, then 702 * set our runtime to that hour before leaping into the 703 * month scanner 704 */ 705 case TEATIME: 706 hr += 4; 707 case NOON: 708 hr += 12; 709 case MIDNIGHT: 710 if (runtime.tm_hour >= hr) { 711 runtime.tm_mday++; 712 runtime.tm_wday++; 713 } 714 runtime.tm_hour = hr; 715 runtime.tm_min = 0; 716 token(); 717 /* FALLTHROUGH to month setting */ 718 default: 719 month(&runtime); 720 break; 721 } /* ugly case statement */ 722 expect(EOF); 723 724 /* convert back to time_t 725 */ 726 runtime.tm_isdst = -1; 727 runtimer = mktime(&runtime); 728 729 if (runtimer < 0) 730 panic("garbled time"); 731 732 if (nowtimer > runtimer) 733 panic("trying to travel back in time"); 734 735 return runtimer; 736} /* parsetime */ 737