parsetime.c revision 1.15.8.1
1 /* $NetBSD: parsetime.c,v 1.15.8.1 2008/03/24 07:16:34 keiichi Exp $ */ 2 3 /* 4 * parsetime.c - parse time for at(1) 5 * Copyright (C) 1993, 1994 Thomas Koenig 6 * 7 * modifications for english-language times 8 * Copyright (C) 1993 David Parsons 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. The name of the author(s) may not be used to endorse or promote 16 * products derived from this software without specific prior written 17 * permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 * 30 * at [NOW] PLUS NUMBER MINUTES|HOURS|DAYS|WEEKS 31 * /NUMBER [DOT NUMBER] [AM|PM]\ /[MONTH NUMBER [NUMBER]] \ 32 * |NOON | |[TOMORROW] | 33 * |MIDNIGHT | |[DAY OF WEEK] | 34 * \TEATIME / |NUMBER [SLASH NUMBER [SLASH NUMBER]]| 35 * \PLUS NUMBER MINUTES|HOURS|DAYS|WEEKS/ 36 */ 37 38 /* System Headers */ 39 40 #include <sys/types.h> 41 #include <err.h> 42 #include <ctype.h> 43 #include <errno.h> 44 #include <stdio.h> 45 #include <stdlib.h> 46 #include <string.h> 47 #include <time.h> 48 #include <tzfile.h> 49 #include <unistd.h> 50 51 /* Local headers */ 52 53 #include "at.h" 54 #include "panic.h" 55 #include "parsetime.h" 56 57 58 /* Structures and unions */ 59 60 enum { /* symbols */ 61 MIDNIGHT, NOON, TEATIME, 62 PM, AM, TOMORROW, TODAY, NOW, 63 MINUTES, HOURS, DAYS, WEEKS, MONTHS, YEARS, 64 NUMBER, PLUS, DOT, SLASH, ID, JUNK, 65 JAN, FEB, MAR, APR, MAY, JUN, 66 JUL, AUG, SEP, OCT, NOV, DEC, 67 SUN, MON, TUE, WED, THU, FRI, SAT 68 }; 69 70 /* 71 * parse translation table - table driven parsers can be your FRIEND! 72 */ 73 struct { 74 char *name; /* token name */ 75 int value; /* token id */ 76 int plural; /* is this plural? */ 77 } Specials[] = { 78 { "midnight", MIDNIGHT, 0 }, /* 00:00:00 of today or tomorrow */ 79 { "noon", NOON, 0 }, /* 12:00:00 of today or tomorrow */ 80 { "teatime", TEATIME, 0 }, /* 16:00:00 of today or tomorrow */ 81 { "am", AM, 0 }, /* morning times for 0-12 clock */ 82 { "pm", PM, 0 }, /* evening times for 0-12 clock */ 83 { "tomorrow", TOMORROW, 0 }, /* execute 24 hours from time */ 84 { "today", TODAY, 0 }, /* execute today - don't advance time */ 85 { "now", NOW, 0 }, /* opt prefix for PLUS */ 86 87 { "minute", MINUTES, 0 }, /* minutes multiplier */ 88 { "min", MINUTES, 0 }, 89 { "m", MINUTES, 0 }, 90 { "minutes", MINUTES, 1 }, /* (pluralized) */ 91 { "hour", HOURS, 0 }, /* hours ... */ 92 { "hr", HOURS, 0 }, /* abbreviated */ 93 { "h", HOURS, 0 }, 94 { "hours", HOURS, 1 }, /* (pluralized) */ 95 { "day", DAYS, 0 }, /* days ... */ 96 { "d", DAYS, 0 }, 97 { "days", DAYS, 1 }, /* (pluralized) */ 98 { "week", WEEKS, 0 }, /* week ... */ 99 { "w", WEEKS, 0 }, 100 { "weeks", WEEKS, 1 }, /* (pluralized) */ 101 { "month", MONTHS, 0 }, /* month ... */ 102 { "months", MONTHS, 1 }, /* (pluralized) */ 103 { "year", YEARS, 0 }, /* year ... */ 104 { "years", YEARS, 1 }, /* (pluralized) */ 105 { "jan", JAN, 0 }, 106 { "feb", FEB, 0 }, 107 { "mar", MAR, 0 }, 108 { "apr", APR, 0 }, 109 { "may", MAY, 0 }, 110 { "jun", JUN, 0 }, 111 { "jul", JUL, 0 }, 112 { "aug", AUG, 0 }, 113 { "sep", SEP, 0 }, 114 { "oct", OCT, 0 }, 115 { "nov", NOV, 0 }, 116 { "dec", DEC, 0 }, 117 { "january", JAN, 0 }, 118 { "february", FEB, 0 }, 119 { "march", MAR, 0 }, 120 { "april", APR, 0 }, 121 { "may", MAY, 0 }, 122 { "june", JUN, 0 }, 123 { "july", JUL, 0 }, 124 { "august", AUG, 0 }, 125 { "september", SEP, 0 }, 126 { "october", OCT, 0 }, 127 { "november", NOV, 0 }, 128 { "december", DEC, 0 }, 129 { "sunday", SUN, 0 }, 130 { "sun", SUN, 0 }, 131 { "monday", MON, 0 }, 132 { "mon", MON, 0 }, 133 { "tuesday", TUE, 0 }, 134 { "tue", TUE, 0 }, 135 { "wednesday", WED, 0 }, 136 { "wed", WED, 0 }, 137 { "thursday", THU, 0 }, 138 { "thu", THU, 0 }, 139 { "friday", FRI, 0 }, 140 { "fri", FRI, 0 }, 141 { "saturday", SAT, 0 }, 142 { "sat", SAT, 0 }, 143 }; 144 145 /* File scope variables */ 146 147 static char **scp; /* scanner - pointer at arglist */ 148 static char scc; /* scanner - count of remaining arguments */ 149 static char *sct; /* scanner - next char pointer in current argument */ 150 static int need; /* scanner - need to advance to next argument */ 151 152 static char *sc_token; /* scanner - token buffer */ 153 static size_t sc_len; /* scanner - length of token buffer */ 154 static int sc_tokid; /* scanner - token id */ 155 static int sc_tokplur; /* scanner - is token plural? */ 156 157 #ifndef lint 158 #if 0 159 static char rcsid[] = "$OpenBSD: parsetime.c,v 1.4 1997/03/01 23:40:10 millert Exp $"; 160 #else 161 __RCSID("$NetBSD: parsetime.c,v 1.15.8.1 2008/03/24 07:16:34 keiichi Exp $"); 162 #endif 163 #endif 164 165 /* Local functions */ 166 static void assign_date (struct tm *, long, long, long); 167 static void expect (int); 168 static void init_scanner (int, char **); 169 static void month (struct tm *); 170 static int parse_token (char *); 171 static void plonk (int); 172 static void plus (struct tm *); 173 static void tod (struct tm *); 174 static int token (void); 175 176 /* 177 * parse a token, checking if it's something special to us 178 */ 179 static int 180 parse_token(char *arg) 181 { 182 int i; 183 184 for (i=0; i < sizeof(Specials) / sizeof(Specials[0]); i++) { 185 if (strcasecmp(Specials[i].name, arg) == 0) { 186 sc_tokplur = Specials[i].plural; 187 return (sc_tokid = Specials[i].value); 188 } 189 } 190 191 /* not special - must be some random id */ 192 return (ID); 193 } /* parse_token */ 194 195 196 /* 197 * init_scanner() sets up the scanner to eat arguments 198 */ 199 static void 200 init_scanner(int argc, char **argv) 201 { 202 scp = argv; 203 scc = argc; 204 need = 1; 205 sc_len = 1; 206 while (argc-- > 0) 207 sc_len += strlen(*argv++); 208 209 if ((sc_token = (char *) malloc(sc_len)) == NULL) 210 panic("Insufficient virtual memory"); 211 } /* init_scanner */ 212 213 /* 214 * token() fetches a token from the input stream 215 */ 216 static int 217 token(void) 218 { 219 int idx; 220 221 while (1) { 222 (void)memset(sc_token, 0, sc_len); 223 sc_tokid = EOF; 224 sc_tokplur = 0; 225 idx = 0; 226 227 /* 228 * if we need to read another argument, walk along the 229 * argument list; when we fall off the arglist, we'll 230 * just return EOF forever 231 */ 232 if (need) { 233 if (scc < 1) 234 return (sc_tokid); 235 sct = *scp; 236 scp++; 237 scc--; 238 need = 0; 239 } 240 /* 241 * eat whitespace now - if we walk off the end of the argument, 242 * we'll continue, which puts us up at the top of the while loop 243 * to fetch the next argument in 244 */ 245 while (isspace((unsigned char)*sct)) 246 ++sct; 247 if (!*sct) { 248 need = 1; 249 continue; 250 } 251 252 /* 253 * preserve the first character of the new token 254 */ 255 sc_token[0] = *sct++; 256 257 /* 258 * then see what it is 259 */ 260 if (isdigit((unsigned char)sc_token[0])) { 261 while (isdigit((unsigned char)*sct)) 262 sc_token[++idx] = *sct++; 263 sc_token[++idx] = 0; 264 return ((sc_tokid = NUMBER)); 265 } else if (isalpha((unsigned char)sc_token[0])) { 266 while (isalpha((unsigned char)*sct)) 267 sc_token[++idx] = *sct++; 268 sc_token[++idx] = 0; 269 return (parse_token(sc_token)); 270 } 271 else if (sc_token[0] == ':' || sc_token[0] == '.') 272 return ((sc_tokid = DOT)); 273 else if (sc_token[0] == '+') 274 return ((sc_tokid = PLUS)); 275 else if (sc_token[0] == '/') 276 return ((sc_tokid = SLASH)); 277 else 278 return ((sc_tokid = JUNK)); 279 } /* while (1) */ 280 } /* token */ 281 282 283 /* 284 * plonk() gives an appropriate error message if a token is incorrect 285 */ 286 static void 287 plonk(int tok) 288 { 289 panic((tok == EOF) ? "incomplete time" : "garbled time"); 290 } /* plonk */ 291 292 293 /* 294 * expect() gets a token and dies most horribly if it's not the token we want 295 */ 296 static void 297 expect(int desired) 298 { 299 if (token() != desired) 300 plonk(sc_tokid); /* and we die here... */ 301 } /* expect */ 302 303 304 /* 305 * plus() parses a now + time 306 * 307 * at [NOW] PLUS NUMBER [MINUTES|HOURS|DAYS|WEEKS|MONTHS|YEARS] 308 * 309 */ 310 static void 311 plus(struct tm *tm) 312 { 313 int delay; 314 int expectplur; 315 316 expect(NUMBER); 317 318 delay = atoi(sc_token); 319 expectplur = (delay != 1) ? 1 : 0; 320 321 switch (token()) { 322 case YEARS: 323 tm->tm_year += delay; 324 break; 325 case MONTHS: 326 tm->tm_mon += delay; 327 break; 328 case WEEKS: 329 delay *= 7; 330 case DAYS: 331 tm->tm_mday += delay; 332 break; 333 case HOURS: 334 tm->tm_hour += delay; 335 break; 336 case MINUTES: 337 tm->tm_min += delay; 338 break; 339 default: 340 plonk(sc_tokid); 341 break; 342 } 343 344 if (expectplur != sc_tokplur) 345 warnx("pluralization is wrong"); 346 347 tm->tm_isdst = -1; 348 if (mktime(tm) == -1) 349 plonk(sc_tokid); 350 } /* plus */ 351 352 353 /* 354 * tod() computes the time of day 355 * [NUMBER [DOT NUMBER] [AM|PM]] 356 */ 357 static void 358 tod(struct tm *tm) 359 { 360 int hour, minute = 0; 361 size_t tlen; 362 363 hour = atoi(sc_token); 364 tlen = strlen(sc_token); 365 366 /* 367 * first pick out the time of day - if it's 4 digits, we assume 368 * a HHMM time, otherwise it's HH DOT MM time 369 */ 370 if (token() == DOT) { 371 expect(NUMBER); 372 minute = atoi(sc_token); 373 token(); 374 } else if (tlen == 4) { 375 minute = hour % 100; 376 hour = hour / 100; 377 } 378 379 if (minute > 59) 380 panic("garbled time"); 381 382 /* 383 * check if an AM or PM specifier was given 384 */ 385 if (sc_tokid == AM || sc_tokid == PM) { 386 if (hour > 12) 387 panic("garbled time"); 388 389 if (sc_tokid == PM) { 390 if (hour != 12) /* 12:xx PM is 12:xx, not 24:xx */ 391 hour += 12; 392 } else { 393 if (hour == 12) /* 12:xx AM is 00:xx, not 12:xx */ 394 hour = 0; 395 } 396 token(); 397 } else if (hour > 23) 398 panic("garbled time"); 399 400 /* 401 * if we specify an absolute time, we don't want to bump the day even 402 * if we've gone past that time - but if we're specifying a time plus 403 * a relative offset, it's okay to bump things 404 */ 405 if ((sc_tokid == EOF || sc_tokid == PLUS) && tm->tm_hour > hour) { 406 tm->tm_mday++; 407 tm->tm_wday++; 408 } 409 410 tm->tm_hour = hour; 411 tm->tm_min = minute; 412 } /* tod */ 413 414 415 /* 416 * assign_date() assigns a date, wrapping to next year if needed 417 */ 418 static void 419 assign_date(struct tm *tm, long mday, long mon, long year) 420 { 421 if (year > 99) { 422 if (year >= TM_YEAR_BASE) 423 year -= TM_YEAR_BASE; 424 else 425 panic("garbled time"); 426 } 427 428 if (year >= 0) { 429 if (year < 70) 430 tm->tm_year = year + 2000 - TM_YEAR_BASE; 431 else 432 tm->tm_year = year + 1900 - TM_YEAR_BASE; 433 } 434 else { /* year < 0 */ 435 if (tm->tm_mon > mon || 436 (tm->tm_mon == mon && tm->tm_mday > mday)) 437 tm->tm_year++; 438 } 439 440 tm->tm_mday = mday; 441 tm->tm_mon = mon; 442 } /* assign_date */ 443 444 445 /* 446 * month() picks apart a month specification 447 * 448 * /[<month> NUMBER [NUMBER]] \ 449 * |[TOMORROW] | 450 * |[DAY OF WEEK] | 451 * |NUMBER [SLASH NUMBER [SLASH NUMBER]]| 452 * \PLUS NUMBER MINUTES|HOURS|DAYS|WEEKS/ 453 */ 454 static void 455 month(struct tm *tm) 456 { 457 int year = (-1); 458 int mday, wday, mon; 459 size_t tlen; 460 461 mday = 0; 462 switch (sc_tokid) { 463 case PLUS: 464 plus(tm); 465 break; 466 467 case TOMORROW: 468 /* do something tomorrow */ 469 tm->tm_mday++; 470 tm->tm_wday++; 471 case TODAY: 472 /* force ourselves to stay in today - no further processing */ 473 token(); 474 break; 475 476 case JAN: case FEB: case MAR: case APR: case MAY: case JUN: 477 case JUL: case AUG: case SEP: case OCT: case NOV: case DEC: 478 /* 479 * do month mday [year] 480 */ 481 mon = sc_tokid - JAN; 482 expect(NUMBER); 483 mday = atoi(sc_token); 484 if (token() == NUMBER) { 485 year = atoi(sc_token); 486 token(); 487 } 488 assign_date(tm, mday, mon, year); 489 break; 490 491 case SUN: case MON: case TUE: 492 case WED: case THU: case FRI: 493 case SAT: 494 /* do a particular day of the week */ 495 wday = sc_tokid - SUN; 496 497 mday = tm->tm_mday; 498 499 /* if this day is < today, then roll to next week */ 500 if (wday < tm->tm_wday) 501 mday += 7 - (tm->tm_wday - wday); 502 else 503 mday += (wday - tm->tm_wday); 504 505 tm->tm_wday = wday; 506 507 assign_date(tm, mday, tm->tm_mon, tm->tm_year + TM_YEAR_BASE); 508 break; 509 510 case NUMBER: 511 /* 512 * get numeric MMDDYY, mm/dd/yy, or dd.mm.yy 513 */ 514 tlen = strlen(sc_token); 515 mon = atoi(sc_token); 516 token(); 517 518 if (sc_tokid == SLASH || sc_tokid == DOT) { 519 int sep; 520 521 sep = sc_tokid; 522 expect(NUMBER); 523 mday = atoi(sc_token); 524 if (token() == sep) { 525 expect(NUMBER); 526 year = atoi(sc_token); 527 token(); 528 } 529 530 /* 531 * flip months and days for european timing 532 */ 533 if (sep == DOT) { 534 int x = mday; 535 mday = mon; 536 mon = x; 537 } 538 } else if (tlen == 6 || tlen == 8) { 539 if (tlen == 8) { 540 year = (mon % 10000) - 1900; 541 mon /= 10000; 542 } else { 543 year = mon % 100; 544 mon /= 100; 545 } 546 mday = mon % 100; 547 mon /= 100; 548 } else 549 panic("garbled time"); 550 551 mon--; 552 if (mon < 0 || mon > 11 || mday < 1 || mday > 31) 553 panic("garbled time"); 554 555 assign_date(tm, mday, mon, year); 556 break; 557 } /* case */ 558 } /* month */ 559 560 561 /* Global functions */ 562 563 time_t 564 parsetime(int argc, char **argv) 565 { 566 /* 567 * Do the argument parsing, die if necessary, and return the 568 * time the job should be run. 569 */ 570 time_t nowtimer, runtimer; 571 struct tm nowtime, runtime; 572 int hr = 0; /* this MUST be initialized to zero for 573 midnight/noon/teatime */ 574 575 nowtimer = time(NULL); 576 nowtime = *localtime(&nowtimer); 577 578 runtime = nowtime; 579 runtime.tm_sec = 0; 580 581 if (argc <= optind) 582 usage(); 583 584 init_scanner(argc - optind, argv + optind); 585 586 switch (token()) { 587 case NOW: 588 if (scc < 1) 589 return nowtimer; 590 591 /* now is optional prefix for PLUS tree */ 592 expect(PLUS); 593 /*FALLTHROUGH*/ 594 case PLUS: 595 plus(&runtime); 596 break; 597 598 case NUMBER: 599 tod(&runtime); 600 month(&runtime); 601 break; 602 603 /* 604 * evil coding for TEATIME|NOON|MIDNIGHT - we've initialised 605 * hr to zero up above, then fall into this case in such a 606 * way so we add +12 +4 hours to it for teatime, +12 hours 607 * to it for noon, and nothing at all for midnight, then 608 * set our runtime to that hour before leaping into the 609 * month scanner 610 */ 611 case TEATIME: 612 hr += 4; 613 case NOON: 614 hr += 12; 615 case MIDNIGHT: 616 if (runtime.tm_hour >= hr) { 617 runtime.tm_mday++; 618 runtime.tm_wday++; 619 } 620 runtime.tm_hour = hr; 621 runtime.tm_min = 0; 622 token(); 623 /* fall through to month setting */ 624 default: 625 month(&runtime); 626 break; 627 } /* ugly case statement */ 628 expect(EOF); 629 630 /* 631 * convert back to time_t 632 */ 633 runtime.tm_isdst = -1; 634 runtimer = mktime(&runtime); 635 636 if (runtimer < 0) 637 panic("Invalid time"); 638 639 if (nowtimer > runtimer) 640 panic("Trying to travel back in time"); 641 642 return (runtimer); 643 } /* parsetime */ 644
Indexes created Mon Oct 20 20:10:13 GMT 2025