3 * March 2005: Further modified and simplified by Tim Kientzle:
4 * Eliminate minutes-based calculations (just do everything in
5 * seconds), have lexer only recognize unsigned integers (handle '+'
6 * and '-' characters in grammar), combine tables into one table with
7 * explicit abbreviation notes, do am/pm adjustments in the grammar
8 * (eliminate some state variables and post-processing). Among other
9 * things, these changes eliminated two shift/reduce conflicts. (Went
14 ** Originally written by Steven M. Bellovin <smb@research.att.com> while
15 ** at the University of North Carolina at Chapel Hill. Later tweaked by
16 ** a couple of people on Usenet. Completely overhauled by Rich $alz
17 ** <rsalz@bbn.com> and Jim Berets <jberets@bbn.com> in August, 1990;
19 ** This grammar has 10 shift/reduce conflicts.
21 ** This code is in the public domain and has no copyright.
23 /* SUPPRESS 287 on yaccpar_sccsid *//* Unused static variable */
24 /* SUPPRESS 288 on yyerrlab *//* Label unused */
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD: src/usr.bin/tar/getdate.y,v 1.6 2006/03/21 17:03:51 kientzle Exp $");
37 #define yyparse getdate_yyparse
38 #define yylex getdate_yylex
39 #define yyerror getdate_yyerror
41 static int yyparse(void);
42 static int yylex(void);
43 static int yyerror(const char *);
45 time_t get_date(char *);
48 #define HOUR(x) ((time_t)(x) * 60)
49 #define SECSPERDAY (24L * 60L * 60L)
52 ** Daylight-savings mode: on, off, or not yet known.
54 typedef enum _DSTMODE {
55 DSTon, DSToff, DSTmaybe
59 ** Meridian: am or pm.
64 ** Global variables. We could get rid of most of these by using a good
65 ** union as the yacc stack. (This routine was originally written before
66 ** yacc had the %union construct.) Maybe someday; right now we only use
67 ** the %union very rarely.
71 static DSTMODE yyDSTmode;
72 static time_t yyDayOrdinal;
73 static time_t yyDayNumber;
74 static int yyHaveDate;
77 static int yyHaveTime;
78 static int yyHaveZone;
79 static time_t yyTimezone;
82 static time_t yyMinutes;
83 static time_t yyMonth;
84 static time_t yySeconds;
86 static time_t yyRelMonth;
87 static time_t yyRelSeconds;
95 %token tAGO tDAY tDAYZONE tAMPM tMONTH tMONTH_UNIT tSEC_UNIT tUNUMBER
98 %type <Number> tDAY tDAYZONE tMONTH tMONTH_UNIT
99 %type <Number> tSEC_UNIT tUNUMBER tZONE tAMPM
107 item : time { yyHaveTime++; }
108 | zone { yyHaveZone++; }
109 | date { yyHaveDate++; }
110 | day { yyHaveDay++; }
111 | rel { yyHaveRel++; }
115 time : tUNUMBER tAMPM {
126 /* "7:12:18" "19:17" */
129 /* "7:12pm", "12:20:13am" */
135 | bare_time '+' tUNUMBER {
138 yyTimezone = - ($3 % 100 + ($3 / 100) * 60);
140 | bare_time '-' tUNUMBER {
141 /* "19:14:12-0530" */
143 yyTimezone = + ($3 % 100 + ($3 / 100) * 60);
147 bare_time : tUNUMBER ':' tUNUMBER {
152 | tUNUMBER ':' tUNUMBER ':' tUNUMBER {
178 /* "tue," "wednesday," */
183 /* "second tues" "3 wed" */
189 date : tUNUMBER '/' tUNUMBER {
194 | tUNUMBER '/' tUNUMBER '/' tUNUMBER {
196 /* First number is big: 2004/01/29, 99/02/17 */
200 } else if (($5 >= 13) || ($3 >= 13)) {
201 /* Last number is big: 01/07/98 */
202 /* Middle number is big: 01/29/04 */
207 /* No significant clues: 02/03/04 */
213 | tUNUMBER '-' tUNUMBER '-' tUNUMBER {
214 /* ISO 8601 format. yyyy-mm-dd. */
219 | tUNUMBER '-' tMONTH '-' tUNUMBER {
221 /* e.g. 1992-Jun-17 */
226 /* e.g. 17-JUN-1992. */
237 | tMONTH tUNUMBER ',' tUNUMBER {
238 /* "June 17, 2001" */
248 | tUNUMBER tMONTH tUNUMBER {
257 yyRelSeconds = -yyRelSeconds;
258 yyRelMonth = -yyRelMonth;
263 relunit : '-' tUNUMBER tSEC_UNIT {
265 yyRelSeconds -= $2 * $3;
267 | '+' tUNUMBER tSEC_UNIT {
269 yyRelSeconds += $2 * $3;
271 | tUNUMBER tSEC_UNIT {
279 | '-' tUNUMBER tMONTH_UNIT {
281 yyRelMonth -= $2 * $3;
283 | '+' tUNUMBER tMONTH_UNIT {
285 yyRelMonth += $2 * $3;
287 | tUNUMBER tMONTH_UNIT {
289 yyRelMonth += $1 * $2;
298 if (yyHaveTime && yyHaveDate && !yyHaveRel)
305 yyMonth= ($1/100)%100;
309 /* "513" is same as "5:13" */
317 yyMinutes = $1 % 100;
328 static struct TABLE {
333 } const TimeWords[] = {
335 { 0, "am", tAMPM, tAM },
336 { 0, "pm", tAMPM, tPM },
339 { 3, "january", tMONTH, 1 },
340 { 3, "february", tMONTH, 2 },
341 { 3, "march", tMONTH, 3 },
342 { 3, "april", tMONTH, 4 },
343 { 3, "may", tMONTH, 5 },
344 { 3, "june", tMONTH, 6 },
345 { 3, "july", tMONTH, 7 },
346 { 3, "august", tMONTH, 8 },
347 { 3, "september", tMONTH, 9 },
348 { 3, "october", tMONTH, 10 },
349 { 3, "november", tMONTH, 11 },
350 { 3, "december", tMONTH, 12 },
352 /* Days of the week. */
353 { 2, "sunday", tDAY, 0 },
354 { 3, "monday", tDAY, 1 },
355 { 2, "tuesday", tDAY, 2 },
356 { 3, "wednesday", tDAY, 3 },
357 { 2, "thursday", tDAY, 4 },
358 { 2, "friday", tDAY, 5 },
359 { 2, "saturday", tDAY, 6 },
361 /* Timezones: Offsets are in minutes. */
362 { 0, "gmt", tZONE, HOUR( 0) }, /* Greenwich Mean */
363 { 0, "ut", tZONE, HOUR( 0) }, /* Universal (Coordinated) */
364 { 0, "utc", tZONE, HOUR( 0) },
365 { 0, "wet", tZONE, HOUR( 0) }, /* Western European */
366 { 0, "bst", tDAYZONE, HOUR( 0) }, /* British Summer */
367 { 0, "wat", tZONE, HOUR( 1) }, /* West Africa */
368 { 0, "at", tZONE, HOUR( 2) }, /* Azores */
369 /* { 0, "bst", tZONE, HOUR( 3) }, */ /* Brazil Standard: Conflict */
370 /* { 0, "gst", tZONE, HOUR( 3) }, */ /* Greenland Standard: Conflict*/
371 { 0, "nft", tZONE, HOUR(3)+30 }, /* Newfoundland */
372 { 0, "nst", tZONE, HOUR(3)+30 }, /* Newfoundland Standard */
373 { 0, "ndt", tDAYZONE, HOUR(3)+30 }, /* Newfoundland Daylight */
374 { 0, "ast", tZONE, HOUR( 4) }, /* Atlantic Standard */
375 { 0, "adt", tDAYZONE, HOUR( 4) }, /* Atlantic Daylight */
376 { 0, "est", tZONE, HOUR( 5) }, /* Eastern Standard */
377 { 0, "edt", tDAYZONE, HOUR( 5) }, /* Eastern Daylight */
378 { 0, "cst", tZONE, HOUR( 6) }, /* Central Standard */
379 { 0, "cdt", tDAYZONE, HOUR( 6) }, /* Central Daylight */
380 { 0, "mst", tZONE, HOUR( 7) }, /* Mountain Standard */
381 { 0, "mdt", tDAYZONE, HOUR( 7) }, /* Mountain Daylight */
382 { 0, "pst", tZONE, HOUR( 8) }, /* Pacific Standard */
383 { 0, "pdt", tDAYZONE, HOUR( 8) }, /* Pacific Daylight */
384 { 0, "yst", tZONE, HOUR( 9) }, /* Yukon Standard */
385 { 0, "ydt", tDAYZONE, HOUR( 9) }, /* Yukon Daylight */
386 { 0, "hst", tZONE, HOUR(10) }, /* Hawaii Standard */
387 { 0, "hdt", tDAYZONE, HOUR(10) }, /* Hawaii Daylight */
388 { 0, "cat", tZONE, HOUR(10) }, /* Central Alaska */
389 { 0, "ahst", tZONE, HOUR(10) }, /* Alaska-Hawaii Standard */
390 { 0, "nt", tZONE, HOUR(11) }, /* Nome */
391 { 0, "idlw", tZONE, HOUR(12) }, /* Intl Date Line West */
392 { 0, "cet", tZONE, -HOUR(1) }, /* Central European */
393 { 0, "met", tZONE, -HOUR(1) }, /* Middle European */
394 { 0, "mewt", tZONE, -HOUR(1) }, /* Middle European Winter */
395 { 0, "mest", tDAYZONE, -HOUR(1) }, /* Middle European Summer */
396 { 0, "swt", tZONE, -HOUR(1) }, /* Swedish Winter */
397 { 0, "sst", tDAYZONE, -HOUR(1) }, /* Swedish Summer */
398 { 0, "fwt", tZONE, -HOUR(1) }, /* French Winter */
399 { 0, "fst", tDAYZONE, -HOUR(1) }, /* French Summer */
400 { 0, "eet", tZONE, -HOUR(2) }, /* Eastern Eur, USSR Zone 1 */
401 { 0, "bt", tZONE, -HOUR(3) }, /* Baghdad, USSR Zone 2 */
402 { 0, "it", tZONE, -HOUR(3)-30 },/* Iran */
403 { 0, "zp4", tZONE, -HOUR(4) }, /* USSR Zone 3 */
404 { 0, "zp5", tZONE, -HOUR(5) }, /* USSR Zone 4 */
405 { 0, "ist", tZONE, -HOUR(5)-30 },/* Indian Standard */
406 { 0, "zp6", tZONE, -HOUR(6) }, /* USSR Zone 5 */
407 /* { 0, "nst", tZONE, -HOUR(6.5) }, */ /* North Sumatra: Conflict */
408 /* { 0, "sst", tZONE, -HOUR(7) }, */ /* So Sumatra, USSR 6: Conflict */
409 { 0, "wast", tZONE, -HOUR(7) }, /* West Australian Standard */
410 { 0, "wadt", tDAYZONE, -HOUR(7) }, /* West Australian Daylight */
411 { 0, "jt", tZONE, -HOUR(7)-30 },/* Java (3pm in Cronusland!)*/
412 { 0, "cct", tZONE, -HOUR(8) }, /* China Coast, USSR Zone 7 */
413 { 0, "jst", tZONE, -HOUR(9) }, /* Japan Std, USSR Zone 8 */
414 { 0, "cast", tZONE, -HOUR(9)-30 },/* Central Australian Std */
415 { 0, "cadt", tDAYZONE, -HOUR(9)-30 },/* Central Australian Daylt */
416 { 0, "east", tZONE, -HOUR(10) }, /* Eastern Australian Std */
417 { 0, "eadt", tDAYZONE, -HOUR(10) }, /* Eastern Australian Daylt */
418 { 0, "gst", tZONE, -HOUR(10) }, /* Guam Std, USSR Zone 9 */
419 { 0, "nzt", tZONE, -HOUR(12) }, /* New Zealand */
420 { 0, "nzst", tZONE, -HOUR(12) }, /* New Zealand Standard */
421 { 0, "nzdt", tDAYZONE, -HOUR(12) }, /* New Zealand Daylight */
422 { 0, "idle", tZONE, -HOUR(12) }, /* Intl Date Line East */
424 { 0, "dst", tDST, 0 },
427 { 4, "years", tMONTH_UNIT, 12 },
428 { 5, "months", tMONTH_UNIT, 1 },
429 { 9, "fortnights", tSEC_UNIT, 14 * 24 * 60 * 60 },
430 { 4, "weeks", tSEC_UNIT, 7 * 24 * 60 * 60 },
431 { 3, "days", tSEC_UNIT, 1 * 24 * 60 * 60 },
432 { 4, "hours", tSEC_UNIT, 60 * 60 },
433 { 3, "minutes", tSEC_UNIT, 60 },
434 { 3, "seconds", tSEC_UNIT, 1 },
436 /* Relative-time words. */
437 { 0, "tomorrow", tSEC_UNIT, 1 * 24 * 60 * 60 },
438 { 0, "yesterday", tSEC_UNIT, -1 * 24 * 60 * 60 },
439 { 0, "today", tSEC_UNIT, 0 },
440 { 0, "now", tSEC_UNIT, 0 },
441 { 0, "last", tUNUMBER, -1 },
442 { 0, "this", tSEC_UNIT, 0 },
443 { 0, "next", tUNUMBER, 2 },
444 { 0, "first", tUNUMBER, 1 },
445 { 0, "1st", tUNUMBER, 1 },
446 /* { 0, "second", tUNUMBER, 2 }, */
447 { 0, "2nd", tUNUMBER, 2 },
448 { 0, "third", tUNUMBER, 3 },
449 { 0, "3rd", tUNUMBER, 3 },
450 { 0, "fourth", tUNUMBER, 4 },
451 { 0, "4th", tUNUMBER, 4 },
452 { 0, "fifth", tUNUMBER, 5 },
453 { 0, "5th", tUNUMBER, 5 },
454 { 0, "sixth", tUNUMBER, 6 },
455 { 0, "seventh", tUNUMBER, 7 },
456 { 0, "eighth", tUNUMBER, 8 },
457 { 0, "ninth", tUNUMBER, 9 },
458 { 0, "tenth", tUNUMBER, 10 },
459 { 0, "eleventh", tUNUMBER, 11 },
460 { 0, "twelfth", tUNUMBER, 12 },
461 { 0, "ago", tAGO, 1 },
463 /* Military timezones. */
464 { 0, "a", tZONE, HOUR( 1) },
465 { 0, "b", tZONE, HOUR( 2) },
466 { 0, "c", tZONE, HOUR( 3) },
467 { 0, "d", tZONE, HOUR( 4) },
468 { 0, "e", tZONE, HOUR( 5) },
469 { 0, "f", tZONE, HOUR( 6) },
470 { 0, "g", tZONE, HOUR( 7) },
471 { 0, "h", tZONE, HOUR( 8) },
472 { 0, "i", tZONE, HOUR( 9) },
473 { 0, "k", tZONE, HOUR( 10) },
474 { 0, "l", tZONE, HOUR( 11) },
475 { 0, "m", tZONE, HOUR( 12) },
476 { 0, "n", tZONE, HOUR(- 1) },
477 { 0, "o", tZONE, HOUR(- 2) },
478 { 0, "p", tZONE, HOUR(- 3) },
479 { 0, "q", tZONE, HOUR(- 4) },
480 { 0, "r", tZONE, HOUR(- 5) },
481 { 0, "s", tZONE, HOUR(- 6) },
482 { 0, "t", tZONE, HOUR(- 7) },
483 { 0, "u", tZONE, HOUR(- 8) },
484 { 0, "v", tZONE, HOUR(- 9) },
485 { 0, "w", tZONE, HOUR(-10) },
486 { 0, "x", tZONE, HOUR(-11) },
487 { 0, "y", tZONE, HOUR(-12) },
488 { 0, "z", tZONE, HOUR( 0) },
499 yyerror(const char *s)
506 ToSeconds(time_t Hours, time_t Minutes, time_t Seconds)
508 if (Minutes < 0 || Minutes > 59 || Seconds < 0 || Seconds > 59)
510 if (Hours < 0 || Hours > 23)
512 return (Hours * 60L + Minutes) * 60L + Seconds;
517 * A number from 0 to 99, which means a year from 1970 to 2069, or
518 * The actual year (>=100). */
520 Convert(time_t Month, time_t Day, time_t Year,
521 time_t Hours, time_t Minutes, time_t Seconds, DSTMODE DSTmode)
523 static int DaysInMonth[12] = {
524 31, 0, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
534 DaysInMonth[1] = Year % 4 == 0 && (Year % 100 != 0 || Year % 400 == 0)
536 /* Checking for 2038 bogusly assumes that time_t is 32 bits. But
537 I'm too lazy to try to check for time_t overflow in another way. */
538 if (Year < EPOCH || Year > 2038
539 || Month < 1 || Month > 12
540 /* Lint fluff: "conversion from long may lose accuracy" */
541 || Day < 1 || Day > DaysInMonth[(int)--Month])
545 for (i = 0; i < Month; i++)
546 Julian += DaysInMonth[i];
547 for (i = EPOCH; i < Year; i++)
548 Julian += 365 + (i % 4 == 0);
549 Julian *= SECSPERDAY;
550 Julian += yyTimezone * 60L;
551 if ((tod = ToSeconds(Hours, Minutes, Seconds)) < 0)
555 || (DSTmode == DSTmaybe && localtime(&Julian)->tm_isdst))
562 DSTcorrect(time_t Start, time_t Future)
567 StartDay = (localtime(&Start)->tm_hour + 1) % 24;
568 FutureDay = (localtime(&Future)->tm_hour + 1) % 24;
569 return (Future - Start) + (StartDay - FutureDay) * 60L * 60L;
574 RelativeDate(time_t Start, time_t DayOrdinal, time_t DayNumber)
580 tm = localtime(&now);
581 now += SECSPERDAY * ((DayNumber - tm->tm_wday + 7) % 7);
582 now += 7 * SECSPERDAY * (DayOrdinal <= 0 ? DayOrdinal : DayOrdinal - 1);
583 return DSTcorrect(Start, now);
588 RelativeMonth(time_t Start, time_t RelMonth)
596 tm = localtime(&Start);
597 Month = 12 * (tm->tm_year + 1900) + tm->tm_mon + RelMonth;
599 Month = Month % 12 + 1;
600 return DSTcorrect(Start,
601 Convert(Month, (time_t)tm->tm_mday, Year,
602 (time_t)tm->tm_hour, (time_t)tm->tm_min, (time_t)tm->tm_sec,
613 while (isspace(*yyInput))
616 /* Skip parenthesized comments. */
617 if (*yyInput == '(') {
631 /* Try the next token in the word table first. */
632 /* This allows us to match "2nd", for example. */
635 const struct TABLE *tp;
638 /* Force to lowercase and strip '.' characters. */
640 && (isalnum(*src) || *src == '.')
641 && i < sizeof(buff)-1) {
644 buff[i++] = tolower(*src);
653 * Find the first match. If the word can be
654 * abbreviated, make sure we match at least
655 * the minimum abbreviation.
657 for (tp = TimeWords; tp->name; tp++) {
658 size_t abbrev = tp->abbrev;
660 abbrev = strlen(tp->name);
661 if (strlen(buff) >= abbrev
662 && strncmp(tp->name, buff, strlen(buff))
664 /* Skip over token. */
666 /* Return the match. */
667 yylval.Number = tp->value;
674 * Not in the word table, maybe it's a number. Note:
675 * Because '-' and '+' have other special meanings, I
676 * don't deal with signed numbers here.
678 if (isdigit(c = *yyInput)) {
679 for (yylval.Number = 0; isdigit(c = *yyInput++); )
680 yylval.Number = 10 * yylval.Number + c - '0';
689 #define TM_YEAR_ORIGIN 1900
691 /* Yield A - B, measured in seconds. */
693 difftm (struct tm *a, struct tm *b)
695 int ay = a->tm_year + (TM_YEAR_ORIGIN - 1);
696 int by = b->tm_year + (TM_YEAR_ORIGIN - 1);
698 /* difference in day of year */
699 a->tm_yday - b->tm_yday
700 /* + intervening leap days */
701 + ((ay >> 2) - (by >> 2))
703 + ((ay/100 >> 2) - (by/100 >> 2))
704 /* + difference in years * 365 */
705 + (long)(ay-by) * 365
707 return (60*(60*(24*days + (a->tm_hour - b->tm_hour))
708 + (a->tm_min - b->tm_min))
709 + (a->tm_sec - b->tm_sec));
716 struct tm gmt, *gmt_ptr;
722 memset(&gmt, 0, sizeof(gmt));
725 (void)time (&nowtime);
727 gmt_ptr = gmtime (&nowtime);
728 if (gmt_ptr != NULL) {
729 /* Copy, in case localtime and gmtime use the same buffer. */
733 if (! (tm = localtime (&nowtime)))
737 tzone = difftm (&gmt, tm) / 60;
739 /* This system doesn't understand timezones; fake it. */
744 yyYear = tm->tm_year + 1900;
745 yyMonth = tm->tm_mon + 1;
748 yyDSTmode = DSTmaybe;
761 || yyHaveTime > 1 || yyHaveZone > 1
762 || yyHaveDate > 1 || yyHaveDay > 1)
765 if (yyHaveDate || yyHaveTime || yyHaveDay) {
766 Start = Convert(yyMonth, yyDay, yyYear,
767 yyHour, yyMinutes, yySeconds, yyDSTmode);
773 Start -= ((tm->tm_hour * 60L + tm->tm_min) * 60L) + tm->tm_sec;
776 Start += yyRelSeconds;
777 Start += RelativeMonth(Start, yyRelMonth);
779 if (yyHaveDay && !yyHaveDate) {
780 tod = RelativeDate(Start, yyDayOrdinal, yyDayNumber);
784 /* Have to do *something* with a legitimate -1 so it's
785 * distinguishable from the error return value. (Alternately
786 * could set errno on error.) */
787 return Start == -1 ? 0 : Start;
795 main(int argc, char **argv)
799 while (*++argv != NULL) {
800 (void)printf("Input: %s\n", *argv);
803 (void)printf("Bad format - couldn't convert.\n");
805 (void)printf("Output: %s\n", ctime(&d));
810 #endif /* defined(TEST) */