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