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 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} ; 144 145/* File scope variables */ 146 147static char **scp; /* scanner - pointer at arglist */ 148static char scc; /* scanner - count of remaining arguments */ 149static char *sct; /* scanner - next char pointer in current argument */ 150static int need; /* scanner - need to advance to next argument */ 151 152static char *sc_token; /* scanner - token buffer */ 153static size_t sc_len; /* scanner - length of token buffer */ 154static int sc_tokid; /* scanner - token id */ 155static int sc_tokplur; /* scanner - is token plural? */ 156 157/* Local functions */ 158 159/* 160 * parse a token, checking if it's something special to us 161 */ 162static int 163parse_token(char *arg) 164{ 165 size_t i; 166 167 for (i=0; i<(sizeof Specials/sizeof Specials[0]); i++) 168 if (strcasecmp(Specials[i].name, arg) == 0) { 169 sc_tokplur = Specials[i].plural; 170 return sc_tokid = Specials[i].value; 171 } 172 173 /* not special - must be some random id */ 174 return ID; 175} /* parse_token */ 176 177 178/* 179 * init_scanner() sets up the scanner to eat arguments 180 */ 181static void 182init_scanner(int argc, char **argv) 183{ 184 scp = argv; 185 scc = argc; 186 need = 1; 187 sc_len = 1; 188 while (argc-- > 0) 189 sc_len += strlen(*argv++); 190 191 if ((sc_token = malloc(sc_len)) == NULL) 192 errx(EXIT_FAILURE, "virtual memory exhausted"); 193} /* init_scanner */ 194 195/* 196 * token() fetches a token from the input stream 197 */ 198static int 199token(void) 200{ 201 int idx; 202 203 while (1) { 204 memset(sc_token, 0, sc_len); 205 sc_tokid = EOF; 206 sc_tokplur = 0; 207 idx = 0; 208 209 /* if we need to read another argument, walk along the argument list; 210 * when we fall off the arglist, we'll just return EOF forever 211 */ 212 if (need) { 213 if (scc < 1) 214 return sc_tokid; 215 sct = *scp; 216 scp++; 217 scc--; 218 need = 0; 219 } 220 /* eat whitespace now - if we walk off the end of the argument, 221 * we'll continue, which puts us up at the top of the while loop 222 * to fetch the next argument in 223 */ 224 while (isspace(*sct)) 225 ++sct; 226 if (!*sct) { 227 need = 1; 228 continue; 229 } 230 231 /* preserve the first character of the new token 232 */ 233 sc_token[0] = *sct++; 234 235 /* then see what it is 236 */ 237 if (isdigit(sc_token[0])) { 238 while (isdigit(*sct)) 239 sc_token[++idx] = *sct++; 240 sc_token[++idx] = 0; 241 return sc_tokid = NUMBER; 242 } 243 else if (isalpha(sc_token[0])) { 244 while (isalpha(*sct)) 245 sc_token[++idx] = *sct++; 246 sc_token[++idx] = 0; 247 return parse_token(sc_token); 248 } 249 else if (sc_token[0] == ':' || sc_token[0] == '.') 250 return sc_tokid = DOT; 251 else if (sc_token[0] == '+') 252 return sc_tokid = PLUS; 253 else if (sc_token[0] == '/') 254 return sc_tokid = SLASH; 255 else if (sc_token[0] == ',') 256 return sc_tokid = COMMA; 257 else 258 return sc_tokid = JUNK; 259 } /* while (1) */ 260} /* token */ 261 262 263/* 264 * plonk() gives an appropriate error message if a token is incorrect 265 */ 266static void 267plonk(int tok) 268{ 269 panic((tok == EOF) ? "incomplete time" 270 : "garbled time"); 271} /* plonk */ 272 273 274/* 275 * expect() gets a token and dies most horribly if it's not the token we want 276 */ 277static void 278expect(int desired) 279{ 280 if (token() != desired) 281 plonk(sc_tokid); /* and we die here... */ 282} /* expect */ 283 284 285/* 286 * plus() parses a now + time 287 * 288 * at [NOW] PLUS NUMBER [MINUTES|HOURS|DAYS|WEEKS|MONTHS|YEARS] 289 * 290 */ 291 292static void 293plus(struct tm *tm) 294{ 295 int delay; 296 int expectplur; 297 298 expect(NUMBER); 299 300 delay = atoi(sc_token); 301 expectplur = (delay != 1) ? 1 : 0; 302 303 switch (token()) { 304 case YEARS: 305 tm->tm_year += delay; 306 break; 307 case MONTHS: 308 tm->tm_mon += delay; 309 break; 310 case WEEKS: 311 delay *= 7; 312 case DAYS: 313 tm->tm_mday += delay; 314 break; 315 case HOURS: 316 tm->tm_hour += delay; 317 break; 318 case MINUTES: 319 tm->tm_min += delay; 320 break; 321 default: 322 plonk(sc_tokid); 323 break; 324 } 325 326 if (expectplur != sc_tokplur) 327 warnx("pluralization is wrong"); 328 329 tm->tm_isdst = -1; 330 if (mktime(tm) < 0) 331 plonk(sc_tokid); 332 333} /* plus */ 334 335 336/* 337 * tod() computes the time of day 338 * [NUMBER [DOT NUMBER] [AM|PM]] [UTC] 339 */ 340static void 341tod(struct tm *tm) 342{ 343 int hour, minute = 0; 344 size_t tlen; 345 346 hour = atoi(sc_token); 347 tlen = strlen(sc_token); 348 349 /* first pick out the time of day - if it's 4 digits, we assume 350 * a HHMM time, otherwise it's HH DOT MM time 351 */ 352 if (token() == DOT) { 353 expect(NUMBER); 354 minute = atoi(sc_token); 355 if (minute > 59) 356 panic("garbled time"); 357 token(); 358 } 359 else if (tlen == 4) { 360 minute = hour%100; 361 if (minute > 59) 362 panic("garbled time"); 363 hour = hour/100; 364 } 365 366 /* check if an AM or PM specifier was given 367 */ 368 switch (sc_tokid) { 369 case AM: 370 case PM: 371 if (hour > 12) 372 panic("garbled time"); 373 374 if (sc_tokid == PM) { 375 if (hour != 12) /* 12:xx PM is 12:xx, not 24:xx */ 376 hour += 12; 377 } else { 378 if (hour == 12) /* 12:xx AM is 00:xx, not 12:xx */ 379 hour = 0; 380 } 381 if (UTC != token()) 382 break; /* else fallthrough */ 383 384 case UTC: 385 hour += tm->tm_gmtoff/(60*60); 386 while (hour < 0) 387 hour += 24; 388 minute += (tm->tm_gmtoff/60); 389 while (minute < 0) 390 minute += 60; 391 tm->tm_gmtoff = 0; 392 token(); 393 break; 394 default: 395 if (hour > 23) 396 panic("garbled time"); 397 break; 398 } 399 400 /* if we specify an absolute time, we don't want to bump the day even 401 * if we've gone past that time - but if we're specifying a time plus 402 * a relative offset, it's okay to bump things 403 * If minutes are the same assume tomorrow was meant 404 */ 405 if ((sc_tokid == EOF || sc_tokid == PLUS) && 406 ((tm->tm_hour > hour) || ((tm->tm_hour == hour) && (tm->tm_min >= minute)))) { 407 tm->tm_mday++; 408 tm->tm_wday++; 409 } 410 411 tm->tm_hour = hour; 412 tm->tm_min = minute; 413 if (tm->tm_hour == 24) { 414 tm->tm_hour = 0; 415 tm->tm_mday++; 416 } 417} /* tod */ 418 419 420/* 421 * assign_date() assigns a date, wrapping to next year if needed 422 */ 423static void 424assign_date(struct tm *tm, long mday, long mon, long year) 425{ 426 /* 427 * Convert year into tm_year format (year - 1900). 428 * We may be given the year in 2 digit, 4 digit, or tm_year format. 429 */ 430 if (year != -1) { 431 if (year >= TM_YEAR_BASE) 432 year -= TM_YEAR_BASE; /* convert from 4 digit year */ 433 else if (year < 100) { 434 /* convert from 2 digit year */ 435 struct tm *lt; 436 time_t now; 437 438 time(&now); 439 lt = localtime(&now); 440 441 /* Convert to tm_year assuming current century */ 442 year += (lt->tm_year / 100) * 100; 443 444 if (year == lt->tm_year - 1) year++; 445 else if (year < lt->tm_year) 446 year += 100; /* must be in next century */ 447 } 448 } 449 450 if (year < 0 && 451 (tm->tm_mon > mon ||(tm->tm_mon == mon && tm->tm_mday > mday))) 452 year = tm->tm_year + 1; 453 454 tm->tm_mday = mday; 455 tm->tm_mon = mon; 456 457 if (year >= 0) 458 tm->tm_year = year; 459} /* assign_date */ 460 461 462/* 463 * month() picks apart a month specification 464 * 465 * /[<month> NUMBER [NUMBER]] \ 466 * |[TOMORROW] | 467 * |[DAY OF WEEK] | 468 * |NUMBER [SLASH NUMBER [SLASH NUMBER]]| 469 * \PLUS NUMBER MINUTES|HOURS|DAYS|WEEKS/ 470 */ 471static void 472month(struct tm *tm) 473{ 474 long year= (-1); 475 long mday = 0, wday, mon; 476 int tlen; 477 478 switch (sc_tokid) { 479 case PLUS: 480 plus(tm); 481 break; 482 483 case TOMORROW: 484 /* do something tomorrow */ 485 tm->tm_mday ++; 486 tm->tm_wday ++; 487 case TODAY: /* force ourselves to stay in today - no further processing */ 488 token(); 489 break; 490 491 case JAN: case FEB: case MAR: case APR: case MAY: case JUN: 492 case JUL: case AUG: case SEP: case OCT: case NOV: case DEC: 493 /* do month mday [,year] 494 */ 495 mon = (sc_tokid-JAN); 496 expect(NUMBER); 497 mday = atol(sc_token); 498 if (token() == COMMA) { 499 if (token() == NUMBER) { 500 year = atol(sc_token); 501 token(); 502 } 503 } 504 assign_date(tm, mday, mon, year); 505 if (sc_tokid == PLUS) 506 plus(tm); 507 break; 508 509 case SUN: case MON: case TUE: 510 case WED: case THU: case FRI: 511 case SAT: 512 /* do a particular day of the week 513 */ 514 wday = (sc_tokid-SUN); 515 516 mday = tm->tm_mday; 517 518 /* if this day is < today, then roll to next week 519 */ 520 if (wday < tm->tm_wday) 521 mday += 7 - (tm->tm_wday - wday); 522 else 523 mday += (wday - tm->tm_wday); 524 525 tm->tm_wday = wday; 526 527 assign_date(tm, mday, tm->tm_mon, tm->tm_year); 528 break; 529 530 case NUMBER: 531 /* get numeric MMDDYY, mm/dd/yy, or dd.mm.yy 532 */ 533 tlen = strlen(sc_token); 534 mon = atol(sc_token); 535 token(); 536 537 if (sc_tokid == SLASH || sc_tokid == DOT) { 538 int sep; 539 540 sep = sc_tokid; 541 expect(NUMBER); 542 mday = atol(sc_token); 543 if (token() == sep) { 544 expect(NUMBER); 545 year = atol(sc_token); 546 token(); 547 } 548 549 /* flip months and days for European timing 550 */ 551 if (sep == DOT) { 552 int x = mday; 553 mday = mon; 554 mon = x; 555 } 556 } 557 else if (tlen == 6 || tlen == 8) { 558 if (tlen == 8) { 559 year = (mon % 10000) - TM_YEAR_BASE; 560 mon /= 10000; 561 } 562 else { 563 year = mon % 100; 564 mon /= 100; 565 } 566 mday = mon % 100; 567 mon /= 100; 568 } 569 else 570 panic("garbled time"); 571 572 mon--; 573 if (mon < 0 || mon > 11 || mday < 1 || mday > 31) 574 panic("garbled time"); 575 576 assign_date(tm, mday, mon, year); 577 break; 578 } /* case */ 579} /* month */ 580 581 582/* Global functions */ 583 584time_t 585parsetime(int argc, char **argv) 586{ 587/* Do the argument parsing, die if necessary, and return the time the job 588 * should be run. 589 */ 590 time_t nowtimer, runtimer; 591 struct tm nowtime, runtime; 592 int hr = 0; 593 /* this MUST be initialized to zero for midnight/noon/teatime */ 594 595 nowtimer = time(NULL); 596 nowtime = *localtime(&nowtimer); 597 598 runtime = nowtime; 599 runtime.tm_sec = 0; 600 runtime.tm_isdst = 0; 601 602 if (argc <= optind) 603 usage(); 604 605 init_scanner(argc-optind, argv+optind); 606 607 switch (token()) { 608 case NOW: 609 if (scc < 1) { 610 return nowtimer; 611 } 612 /* now is optional prefix for PLUS tree */ 613 expect(PLUS); 614 case PLUS: 615 plus(&runtime); 616 break; 617 618 case NUMBER: 619 tod(&runtime); 620 month(&runtime); 621 break; 622 623 /* evil coding for TEATIME|NOON|MIDNIGHT - we've initialised 624 * hr to zero up above, then fall into this case in such a 625 * way so we add +12 +4 hours to it for teatime, +12 hours 626 * to it for noon, and nothing at all for midnight, then 627 * set our runtime to that hour before leaping into the 628 * month scanner 629 */ 630 case TEATIME: 631 hr += 4; 632 case NOON: 633 hr += 12; 634 case MIDNIGHT: 635 if (runtime.tm_hour >= hr) { 636 runtime.tm_mday++; 637 runtime.tm_wday++; 638 } 639 runtime.tm_hour = hr; 640 runtime.tm_min = 0; 641 token(); 642 /* FALLTHROUGH to month setting */ 643 default: 644 month(&runtime); 645 break; 646 } /* ugly case statement */ 647 expect(EOF); 648 649 /* convert back to time_t 650 */ 651 runtime.tm_isdst = -1; 652 runtimer = mktime(&runtime); 653 654 if (runtimer < 0) 655 panic("garbled time"); 656 657 if (nowtimer > runtimer) 658 panic("trying to travel back in time"); 659 660 return runtimer; 661} /* parsetime */ 662