2 /* Parse a string into an internal time stamp.
4 Copyright (C) 1999, 2000, 2002, 2003, 2004, 2005 Free Software
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software Foundation,
19 Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
21 /* Originally written by Steven M. Bellovin <smb@research.att.com> while
22 at the University of North Carolina at Chapel Hill. Later tweaked by
23 a couple of people on Usenet. Completely overhauled by Rich $alz
24 <rsalz@bbn.com> and Jim Berets <jberets@bbn.com> in August, 1990.
26 Modified by Paul Eggert <eggert@twinsun.com> in August 1999 to do
27 the right thing about local DST. Also modified by Paul Eggert
28 <eggert@cs.ucla.edu> in February 2004 to support
29 nanosecond-resolution time stamps, and in October 2004 to support
30 TZ strings in dates. */
32 /* FIXME: Check for arithmetic overflow in all cases, not just
41 /* There's no need to extend the stack, so there's no need to involve
43 #define YYSTACK_USE_ALLOCA 0
45 /* Tell Bison how much stack space is needed. 20 should be plenty for
46 this grammar, which is not right recursive. Beware setting it too
47 high, since that might cause problems on machines whose
48 implementations have lame stack-overflow checking. */
50 #define YYINITDEPTH YYMAXDEPTH
52 /* Since the code of getdate.y is not included in the Emacs executable
53 itself, there is no need to #define static in this file. Even if
54 the code were included in the Emacs executable, it probably
55 wouldn't do any harm to #undef it here; this will only cause
56 problems if we try to write to a static variable, which I don't
57 think this code needs to do. */
71 #if STDC_HEADERS || (! defined isascii && ! HAVE_ISASCII)
72 # define IN_CTYPE_DOMAIN(c) 1
74 # define IN_CTYPE_DOMAIN(c) isascii (c)
77 #define ISSPACE(c) (IN_CTYPE_DOMAIN (c) && isspace (c))
78 #define ISALPHA(c) (IN_CTYPE_DOMAIN (c) && isalpha (c))
79 #define ISLOWER(c) (IN_CTYPE_DOMAIN (c) && islower (c))
81 /* ISDIGIT differs from isdigit, as follows:
82 - Its arg may be any int or unsigned int; it need not be an unsigned char.
83 - It's guaranteed to evaluate its argument exactly once.
84 - It's typically faster.
85 POSIX says that only '0' through '9' are digits. Prefer ISDIGIT to
86 isdigit unless it's important to use the locale's definition
87 of `digit' even when the host does not conform to POSIX. */
88 #define ISDIGIT(c) ((unsigned int) (c) - '0' <= 9)
90 #if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8) || __STRICT_ANSI__
91 # define __attribute__(x)
94 #ifndef ATTRIBUTE_UNUSED
95 # define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
98 /* Shift A right by B bits portably, by dividing A by 2**B and
99 truncating towards minus infinity. A and B should be free of side
100 effects, and B should be in the range 0 <= B <= INT_BITS - 2, where
101 INT_BITS is the number of useful bits in an int. GNU code can
102 assume that INT_BITS is at least 32.
104 ISO C99 says that A >> B is implementation-defined if A < 0. Some
105 implementations (e.g., UNICOS 9.0 on a Cray Y-MP EL) don't shift
106 right in the usual way when A < 0, so SHR falls back on division if
107 ordinary A >> B doesn't seem to be the usual signed shift. */
111 : (a) / (1 << (b)) - ((a) % (1 << (b)) < 0))
113 #define EPOCH_YEAR 1970
114 #define TM_YEAR_BASE 1900
116 #define HOUR(x) ((x) * 60)
118 /* An integer value, and the number of digits in its textual
127 /* An entry in the lexical lookup table. */
135 /* Meridian: am, pm, or 24-hour style. */
136 enum { MERam, MERpm, MER24 };
138 enum { BILLION = 1000000000, LOG10_BILLION = 9 };
140 /* Information passed to and from the parser. */
143 /* The input string remaining to be parsed. */
146 /* N, if this is the Nth Tuesday. */
147 long int day_ordinal;
149 /* Day of week; Sunday is 0. */
152 /* tm_isdst flag for the local zone. */
155 /* Time zone, in minutes east of UTC. */
158 /* Style used for time. */
161 /* Gregorian year, month, day, hour, minutes, seconds, and nanoseconds. */
167 struct timespec seconds; /* includes nanoseconds */
169 /* Relative year, month, day, hour, minutes, seconds, and nanoseconds. */
174 long int rel_minutes;
175 long int rel_seconds;
178 /* Presence or counts of nonterminals of various flavors parsed so far. */
183 size_t local_zones_seen;
188 /* Table of local time zone abbrevations, terminated by a null entry. */
189 table local_time_zone_table[3];
193 static int yylex (union YYSTYPE *, parser_control *);
194 static int yyerror (parser_control *, char *);
195 static long int time_zone_hhmm (textint, long int);
199 /* We want a reentrant parser, even if the TZ manipulation and the calls to
200 localtime and gmtime are not reentrant. */
202 %parse-param { parser_control *pc }
203 %lex-param { parser_control *pc }
205 /* This grammar has 20 shift/reduce conflicts. */
212 struct timespec timespec;
217 %token <intval> tDAY tDAY_UNIT tDAYZONE tHOUR_UNIT tLOCAL_ZONE tMERIDIAN
218 %token <intval> tMINUTE_UNIT tMONTH tMONTH_UNIT tORDINAL
219 %token <intval> tSEC_UNIT tYEAR_UNIT tZONE
221 %token <textintval> tSNUMBER tUNUMBER
222 %token <timespec> tSDECIMAL_NUMBER tUDECIMAL_NUMBER
224 %type <intval> o_colon_minutes o_merid
225 %type <timespec> seconds signed_seconds unsigned_seconds
238 pc->timespec_seen = true;
249 { pc->times_seen++; }
251 { pc->local_zones_seen++; }
253 { pc->zones_seen++; }
255 { pc->dates_seen++; }
259 { pc->rels_seen = true; }
268 pc->seconds.tv_sec = 0;
269 pc->seconds.tv_nsec = 0;
272 | tUNUMBER ':' tUNUMBER o_merid
275 pc->minutes = $3.value;
276 pc->seconds.tv_sec = 0;
277 pc->seconds.tv_nsec = 0;
280 | tUNUMBER ':' tUNUMBER tSNUMBER o_colon_minutes
283 pc->minutes = $3.value;
284 pc->seconds.tv_sec = 0;
285 pc->seconds.tv_nsec = 0;
286 pc->meridian = MER24;
288 pc->time_zone = time_zone_hhmm ($4, $5);
290 | tUNUMBER ':' tUNUMBER ':' unsigned_seconds o_merid
293 pc->minutes = $3.value;
297 | tUNUMBER ':' tUNUMBER ':' unsigned_seconds tSNUMBER o_colon_minutes
300 pc->minutes = $3.value;
302 pc->meridian = MER24;
304 pc->time_zone = time_zone_hhmm ($6, $7);
311 pc->local_isdst = $1;
312 pc->dsts_seen += (0 < $1);
317 pc->dsts_seen += (0 < $1) + 1;
323 { pc->time_zone = $1; }
324 | tZONE relunit_snumber
325 { pc->time_zone = $1; pc->rels_seen = true; }
326 | tZONE tSNUMBER o_colon_minutes
327 { pc->time_zone = $1 + time_zone_hhmm ($2, $3); }
329 { pc->time_zone = $1 + 60; }
331 { pc->time_zone = $1 + 60; }
347 pc->day_ordinal = $1;
352 pc->day_ordinal = $1.value;
358 tUNUMBER '/' tUNUMBER
360 pc->month = $1.value;
363 | tUNUMBER '/' tUNUMBER '/' tUNUMBER
365 /* Interpret as YYYY/MM/DD if the first value has 4 or more digits,
366 otherwise as MM/DD/YY.
367 The goal in recognizing YYYY/MM/DD is solely to support legacy
368 machine-generated dates like those in an RCS log listing. If
369 you want portability, use the ISO 8601 format. */
373 pc->month = $3.value;
378 pc->month = $1.value;
383 | tUNUMBER tSNUMBER tSNUMBER
385 /* ISO 8601 format. YYYY-MM-DD. */
387 pc->month = -$2.value;
390 | tUNUMBER tMONTH tSNUMBER
392 /* e.g. 17-JUN-1992. */
395 pc->year.value = -$3.value;
396 pc->year.digits = $3.digits;
398 | tMONTH tSNUMBER tSNUMBER
400 /* e.g. JUN-17-1992. */
403 pc->year.value = -$3.value;
404 pc->year.digits = $3.digits;
411 | tMONTH tUNUMBER ',' tUNUMBER
422 | tUNUMBER tMONTH tUNUMBER
433 pc->rel_ns = -pc->rel_ns;
434 pc->rel_seconds = -pc->rel_seconds;
435 pc->rel_minutes = -pc->rel_minutes;
436 pc->rel_hour = -pc->rel_hour;
437 pc->rel_day = -pc->rel_day;
438 pc->rel_month = -pc->rel_month;
439 pc->rel_year = -pc->rel_year;
446 { pc->rel_year += $1 * $2; }
447 | tUNUMBER tYEAR_UNIT
448 { pc->rel_year += $1.value * $2; }
450 { pc->rel_year += $1; }
451 | tORDINAL tMONTH_UNIT
452 { pc->rel_month += $1 * $2; }
453 | tUNUMBER tMONTH_UNIT
454 { pc->rel_month += $1.value * $2; }
456 { pc->rel_month += $1; }
458 { pc->rel_day += $1 * $2; }
460 { pc->rel_day += $1.value * $2; }
462 { pc->rel_day += $1; }
463 | tORDINAL tHOUR_UNIT
464 { pc->rel_hour += $1 * $2; }
465 | tUNUMBER tHOUR_UNIT
466 { pc->rel_hour += $1.value * $2; }
468 { pc->rel_hour += $1; }
469 | tORDINAL tMINUTE_UNIT
470 { pc->rel_minutes += $1 * $2; }
471 | tUNUMBER tMINUTE_UNIT
472 { pc->rel_minutes += $1.value * $2; }
474 { pc->rel_minutes += $1; }
476 { pc->rel_seconds += $1 * $2; }
478 { pc->rel_seconds += $1.value * $2; }
479 | tSDECIMAL_NUMBER tSEC_UNIT
480 { pc->rel_seconds += $1.tv_sec * $2; pc->rel_ns += $1.tv_nsec * $2; }
481 | tUDECIMAL_NUMBER tSEC_UNIT
482 { pc->rel_seconds += $1.tv_sec * $2; pc->rel_ns += $1.tv_nsec * $2; }
484 { pc->rel_seconds += $1; }
490 { pc->rel_year += $1.value * $2; }
491 | tSNUMBER tMONTH_UNIT
492 { pc->rel_month += $1.value * $2; }
494 { pc->rel_day += $1.value * $2; }
495 | tSNUMBER tHOUR_UNIT
496 { pc->rel_hour += $1.value * $2; }
497 | tSNUMBER tMINUTE_UNIT
498 { pc->rel_minutes += $1.value * $2; }
500 { pc->rel_seconds += $1.value * $2; }
503 seconds: signed_seconds | unsigned_seconds;
508 { $$.tv_sec = $1.value; $$.tv_nsec = 0; }
514 { $$.tv_sec = $1.value; $$.tv_nsec = 0; }
520 if (pc->dates_seen && ! pc->year.digits
521 && ! pc->rels_seen && (pc->times_seen || 2 < $1.digits))
528 pc->day = $1.value % 100;
529 pc->month = ($1.value / 100) % 100;
530 pc->year.value = $1.value / 10000;
531 pc->year.digits = $1.digits - 4;
543 pc->hour = $1.value / 100;
544 pc->minutes = $1.value % 100;
546 pc->seconds.tv_sec = 0;
547 pc->seconds.tv_nsec = 0;
548 pc->meridian = MER24;
570 static table const meridian_table[] =
572 { "AM", tMERIDIAN, MERam },
573 { "A.M.", tMERIDIAN, MERam },
574 { "PM", tMERIDIAN, MERpm },
575 { "P.M.", tMERIDIAN, MERpm },
579 static table const dst_table[] =
584 static table const month_and_day_table[] =
586 { "JANUARY", tMONTH, 1 },
587 { "FEBRUARY", tMONTH, 2 },
588 { "MARCH", tMONTH, 3 },
589 { "APRIL", tMONTH, 4 },
590 { "MAY", tMONTH, 5 },
591 { "JUNE", tMONTH, 6 },
592 { "JULY", tMONTH, 7 },
593 { "AUGUST", tMONTH, 8 },
594 { "SEPTEMBER",tMONTH, 9 },
595 { "SEPT", tMONTH, 9 },
596 { "OCTOBER", tMONTH, 10 },
597 { "NOVEMBER", tMONTH, 11 },
598 { "DECEMBER", tMONTH, 12 },
599 { "SUNDAY", tDAY, 0 },
600 { "MONDAY", tDAY, 1 },
601 { "TUESDAY", tDAY, 2 },
603 { "WEDNESDAY",tDAY, 3 },
604 { "WEDNES", tDAY, 3 },
605 { "THURSDAY", tDAY, 4 },
607 { "THURS", tDAY, 4 },
608 { "FRIDAY", tDAY, 5 },
609 { "SATURDAY", tDAY, 6 },
613 static table const time_units_table[] =
615 { "YEAR", tYEAR_UNIT, 1 },
616 { "MONTH", tMONTH_UNIT, 1 },
617 { "FORTNIGHT",tDAY_UNIT, 14 },
618 { "WEEK", tDAY_UNIT, 7 },
619 { "DAY", tDAY_UNIT, 1 },
620 { "HOUR", tHOUR_UNIT, 1 },
621 { "MINUTE", tMINUTE_UNIT, 1 },
622 { "MIN", tMINUTE_UNIT, 1 },
623 { "SECOND", tSEC_UNIT, 1 },
624 { "SEC", tSEC_UNIT, 1 },
628 /* Assorted relative-time words. */
629 static table const relative_time_table[] =
631 { "TOMORROW", tDAY_UNIT, 1 },
632 { "YESTERDAY",tDAY_UNIT, -1 },
633 { "TODAY", tDAY_UNIT, 0 },
634 { "NOW", tDAY_UNIT, 0 },
635 { "LAST", tORDINAL, -1 },
636 { "THIS", tORDINAL, 0 },
637 { "NEXT", tORDINAL, 1 },
638 { "FIRST", tORDINAL, 1 },
639 /*{ "SECOND", tORDINAL, 2 }, */
640 { "THIRD", tORDINAL, 3 },
641 { "FOURTH", tORDINAL, 4 },
642 { "FIFTH", tORDINAL, 5 },
643 { "SIXTH", tORDINAL, 6 },
644 { "SEVENTH", tORDINAL, 7 },
645 { "EIGHTH", tORDINAL, 8 },
646 { "NINTH", tORDINAL, 9 },
647 { "TENTH", tORDINAL, 10 },
648 { "ELEVENTH", tORDINAL, 11 },
649 { "TWELFTH", tORDINAL, 12 },
654 /* The universal time zone table. These labels can be used even for
655 time stamps that would not otherwise be valid, e.g., GMT time
656 stamps in London during summer. */
657 static table const universal_time_zone_table[] =
659 { "GMT", tZONE, HOUR ( 0) }, /* Greenwich Mean */
660 { "UT", tZONE, HOUR ( 0) }, /* Universal (Coordinated) */
661 { "UTC", tZONE, HOUR ( 0) },
665 /* The time zone table. This table is necessarily incomplete, as time
666 zone abbreviations are ambiguous; e.g. Australians interpret "EST"
667 as Eastern time in Australia, not as US Eastern Standard Time.
668 You cannot rely on getdate to handle arbitrary time zone
669 abbreviations; use numeric abbreviations like `-0500' instead. */
670 static table const time_zone_table[] =
672 { "WET", tZONE, HOUR ( 0) }, /* Western European */
673 { "WEST", tDAYZONE, HOUR ( 0) }, /* Western European Summer */
674 { "BST", tDAYZONE, HOUR ( 0) }, /* British Summer */
675 { "ART", tZONE, -HOUR ( 3) }, /* Argentina */
676 { "BRT", tZONE, -HOUR ( 3) }, /* Brazil */
677 { "BRST", tDAYZONE, -HOUR ( 3) }, /* Brazil Summer */
678 { "NST", tZONE, -(HOUR ( 3) + 30) }, /* Newfoundland Standard */
679 { "NDT", tDAYZONE,-(HOUR ( 3) + 30) }, /* Newfoundland Daylight */
680 { "AST", tZONE, -HOUR ( 4) }, /* Atlantic Standard */
681 { "ADT", tDAYZONE, -HOUR ( 4) }, /* Atlantic Daylight */
682 { "CLT", tZONE, -HOUR ( 4) }, /* Chile */
683 { "CLST", tDAYZONE, -HOUR ( 4) }, /* Chile Summer */
684 { "EST", tZONE, -HOUR ( 5) }, /* Eastern Standard */
685 { "EDT", tDAYZONE, -HOUR ( 5) }, /* Eastern Daylight */
686 { "CST", tZONE, -HOUR ( 6) }, /* Central Standard */
687 { "CDT", tDAYZONE, -HOUR ( 6) }, /* Central Daylight */
688 { "MST", tZONE, -HOUR ( 7) }, /* Mountain Standard */
689 { "MDT", tDAYZONE, -HOUR ( 7) }, /* Mountain Daylight */
690 { "PST", tZONE, -HOUR ( 8) }, /* Pacific Standard */
691 { "PDT", tDAYZONE, -HOUR ( 8) }, /* Pacific Daylight */
692 { "AKST", tZONE, -HOUR ( 9) }, /* Alaska Standard */
693 { "AKDT", tDAYZONE, -HOUR ( 9) }, /* Alaska Daylight */
694 { "HST", tZONE, -HOUR (10) }, /* Hawaii Standard */
695 { "HAST", tZONE, -HOUR (10) }, /* Hawaii-Aleutian Standard */
696 { "HADT", tDAYZONE, -HOUR (10) }, /* Hawaii-Aleutian Daylight */
697 { "SST", tZONE, -HOUR (12) }, /* Samoa Standard */
698 { "WAT", tZONE, HOUR ( 1) }, /* West Africa */
699 { "CET", tZONE, HOUR ( 1) }, /* Central European */
700 { "CEST", tDAYZONE, HOUR ( 1) }, /* Central European Summer */
701 { "MET", tZONE, HOUR ( 1) }, /* Middle European */
702 { "MEZ", tZONE, HOUR ( 1) }, /* Middle European */
703 { "MEST", tDAYZONE, HOUR ( 1) }, /* Middle European Summer */
704 { "MESZ", tDAYZONE, HOUR ( 1) }, /* Middle European Summer */
705 { "EET", tZONE, HOUR ( 2) }, /* Eastern European */
706 { "EEST", tDAYZONE, HOUR ( 2) }, /* Eastern European Summer */
707 { "CAT", tZONE, HOUR ( 2) }, /* Central Africa */
708 { "SAST", tZONE, HOUR ( 2) }, /* South Africa Standard */
709 { "EAT", tZONE, HOUR ( 3) }, /* East Africa */
710 { "MSK", tZONE, HOUR ( 3) }, /* Moscow */
711 { "MSD", tDAYZONE, HOUR ( 3) }, /* Moscow Daylight */
712 { "IST", tZONE, (HOUR ( 5) + 30) }, /* India Standard */
713 { "SGT", tZONE, HOUR ( 8) }, /* Singapore */
714 { "KST", tZONE, HOUR ( 9) }, /* Korea Standard */
715 { "JST", tZONE, HOUR ( 9) }, /* Japan Standard */
716 { "GST", tZONE, HOUR (10) }, /* Guam Standard */
717 { "NZST", tZONE, HOUR (12) }, /* New Zealand Standard */
718 { "NZDT", tDAYZONE, HOUR (12) }, /* New Zealand Daylight */
722 /* Military time zone table. */
723 static table const military_table[] =
725 { "A", tZONE, -HOUR ( 1) },
726 { "B", tZONE, -HOUR ( 2) },
727 { "C", tZONE, -HOUR ( 3) },
728 { "D", tZONE, -HOUR ( 4) },
729 { "E", tZONE, -HOUR ( 5) },
730 { "F", tZONE, -HOUR ( 6) },
731 { "G", tZONE, -HOUR ( 7) },
732 { "H", tZONE, -HOUR ( 8) },
733 { "I", tZONE, -HOUR ( 9) },
734 { "K", tZONE, -HOUR (10) },
735 { "L", tZONE, -HOUR (11) },
736 { "M", tZONE, -HOUR (12) },
737 { "N", tZONE, HOUR ( 1) },
738 { "O", tZONE, HOUR ( 2) },
739 { "P", tZONE, HOUR ( 3) },
740 { "Q", tZONE, HOUR ( 4) },
741 { "R", tZONE, HOUR ( 5) },
742 { "S", tZONE, HOUR ( 6) },
743 { "T", tZONE, HOUR ( 7) },
744 { "U", tZONE, HOUR ( 8) },
745 { "V", tZONE, HOUR ( 9) },
746 { "W", tZONE, HOUR (10) },
747 { "X", tZONE, HOUR (11) },
748 { "Y", tZONE, HOUR (12) },
749 { "Z", tZONE, HOUR ( 0) },
755 /* Convert a time zone expressed as HH:MM into an integer count of
756 minutes. If MM is negative, then S is of the form HHMM and needs
757 to be picked apart; otherwise, S is of the form HH. */
760 time_zone_hhmm (textint s, long int mm)
763 return (s.value / 100) * 60 + s.value % 100;
765 return s.value * 60 + (s.negative ? -mm : mm);
769 to_hour (long int hours, int meridian)
773 default: /* Pacify GCC. */
775 return 0 <= hours && hours < 24 ? hours : -1;
777 return 0 < hours && hours < 12 ? hours : hours == 12 ? 0 : -1;
779 return 0 < hours && hours < 12 ? hours + 12 : hours == 12 ? 12 : -1;
784 to_year (textint textyear)
786 long int year = textyear.value;
791 /* XPG4 suggests that years 00-68 map to 2000-2068, and
792 years 69-99 map to 1969-1999. */
793 else if (textyear.digits == 2)
794 year += year < 69 ? 2000 : 1900;
800 lookup_zone (parser_control const *pc, char const *name)
804 for (tp = universal_time_zone_table; tp->name; tp++)
805 if (strcmp (name, tp->name) == 0)
808 /* Try local zone abbreviations before those in time_zone_table, as
809 the local ones are more likely to be right. */
810 for (tp = pc->local_time_zone_table; tp->name; tp++)
811 if (strcmp (name, tp->name) == 0)
814 for (tp = time_zone_table; tp->name; tp++)
815 if (strcmp (name, tp->name) == 0)
822 /* Yield the difference between *A and *B,
823 measured in seconds, ignoring leap seconds.
824 The body of this function is taken directly from the GNU C Library;
825 see src/strftime.c. */
827 tm_diff (struct tm const *a, struct tm const *b)
829 /* Compute intervening leap days correctly even if year is negative.
830 Take care to avoid int overflow in leap day calculations. */
831 int a4 = SHR (a->tm_year, 2) + SHR (TM_YEAR_BASE, 2) - ! (a->tm_year & 3);
832 int b4 = SHR (b->tm_year, 2) + SHR (TM_YEAR_BASE, 2) - ! (b->tm_year & 3);
833 int a100 = a4 / 25 - (a4 % 25 < 0);
834 int b100 = b4 / 25 - (b4 % 25 < 0);
835 int a400 = SHR (a100, 2);
836 int b400 = SHR (b100, 2);
837 int intervening_leap_days = (a4 - b4) - (a100 - b100) + (a400 - b400);
838 long int ayear = a->tm_year;
839 long int years = ayear - b->tm_year;
840 long int days = (365 * years + intervening_leap_days
841 + (a->tm_yday - b->tm_yday));
842 return (60 * (60 * (24 * days + (a->tm_hour - b->tm_hour))
843 + (a->tm_min - b->tm_min))
844 + (a->tm_sec - b->tm_sec));
846 #endif /* ! HAVE_TM_GMTOFF */
849 lookup_word (parser_control const *pc, char *word)
858 /* Make it uppercase. */
859 for (p = word; *p; p++)
861 unsigned char ch = *p;
866 for (tp = meridian_table; tp->name; tp++)
867 if (strcmp (word, tp->name) == 0)
870 /* See if we have an abbreviation for a month. */
871 wordlen = strlen (word);
872 abbrev = wordlen == 3 || (wordlen == 4 && word[3] == '.');
874 for (tp = month_and_day_table; tp->name; tp++)
875 if ((abbrev ? strncmp (word, tp->name, 3) : strcmp (word, tp->name)) == 0)
878 if ((tp = lookup_zone (pc, word)))
881 if (strcmp (word, dst_table[0].name) == 0)
884 for (tp = time_units_table; tp->name; tp++)
885 if (strcmp (word, tp->name) == 0)
888 /* Strip off any plural and try the units table again. */
889 if (word[wordlen - 1] == 'S')
891 word[wordlen - 1] = '\0';
892 for (tp = time_units_table; tp->name; tp++)
893 if (strcmp (word, tp->name) == 0)
895 word[wordlen - 1] = 'S'; /* For "this" in relative_time_table. */
898 for (tp = relative_time_table; tp->name; tp++)
899 if (strcmp (word, tp->name) == 0)
902 /* Military time zones. */
904 for (tp = military_table; tp->name; tp++)
905 if (word[0] == tp->name[0])
908 /* Drop out any periods and try the time zone table again. */
909 for (period_found = false, p = q = word; (*p = *q); q++)
914 if (period_found && (tp = lookup_zone (pc, word)))
921 yylex (YYSTYPE *lvalp, parser_control *pc)
928 while (c = *pc->input, ISSPACE (c))
931 if (ISDIGIT (c) || c == '-' || c == '+')
935 unsigned long int value;
936 if (c == '-' || c == '+')
938 sign = c == '-' ? -1 : 1;
939 while (c = *++pc->input, ISSPACE (c))
942 /* skip the '-' sign */
948 for (value = 0; ; value *= 10)
950 unsigned long int value1 = value + (c - '0');
957 if (ULONG_MAX / 10 < value)
960 if ((c == '.' || c == ',') && ISDIGIT (p[1]))
965 unsigned long int value1;
967 /* Check for overflow when converting value to time_t. */
985 /* Accumulate fraction, to ns precision. */
988 for (digits = 2; digits <= LOG10_BILLION; digits++)
995 /* Skip excess digits, truncating toward -Infinity. */
997 for (; ISDIGIT (*p); p++)
1003 while (ISDIGIT (*p))
1006 /* Adjust to the timespec convention, which is that
1007 tv_nsec is always a positive offset even if tv_sec is
1017 lvalp->timespec.tv_sec = s;
1018 lvalp->timespec.tv_nsec = ns;
1020 return sign ? tSDECIMAL_NUMBER : tUDECIMAL_NUMBER;
1024 lvalp->textintval.negative = sign < 0;
1027 lvalp->textintval.value = - value;
1028 if (0 < lvalp->textintval.value)
1033 lvalp->textintval.value = value;
1034 if (lvalp->textintval.value < 0)
1037 lvalp->textintval.digits = p - pc->input;
1039 return sign ? tSNUMBER : tUNUMBER;
1051 if (p < buff + sizeof buff - 1)
1055 while (ISALPHA (c) || c == '.');
1058 tp = lookup_word (pc, buff);
1061 lvalp->intval = tp->value;
1066 return *pc->input++;
1082 /* Do nothing if the parser reports an error. */
1084 yyerror (parser_control *pc ATTRIBUTE_UNUSED, char *s ATTRIBUTE_UNUSED)
1089 /* If *TM0 is the old and *TM1 is the new value of a struct tm after
1090 passing it to mktime, return true if it's OK that mktime returned T.
1091 It's not OK if *TM0 has out-of-range members. */
1094 mktime_ok (struct tm const *tm0, struct tm const *tm1, time_t t)
1096 if (t == (time_t) -1)
1098 /* Guard against falsely reporting an error when parsing a time
1099 stamp that happens to equal (time_t) -1, on a host that
1100 supports such a time stamp. */
1101 tm1 = localtime (&t);
1106 return ! ((tm0->tm_sec ^ tm1->tm_sec)
1107 | (tm0->tm_min ^ tm1->tm_min)
1108 | (tm0->tm_hour ^ tm1->tm_hour)
1109 | (tm0->tm_mday ^ tm1->tm_mday)
1110 | (tm0->tm_mon ^ tm1->tm_mon)
1111 | (tm0->tm_year ^ tm1->tm_year));
1114 /* A reasonable upper bound for the size of ordinary TZ strings.
1115 Use heap allocation if TZ's length exceeds this. */
1116 enum { TZBUFSIZE = 100 };
1118 /* Return a copy of TZ, stored in TZBUF if it fits, and heap-allocated
1121 get_tz (char tzbuf[TZBUFSIZE])
1123 char *tz = getenv ("TZ");
1126 size_t tzsize = strlen (tz) + 1;
1127 tz = (tzsize <= TZBUFSIZE
1128 ? memcpy (tzbuf, tz, tzsize)
1129 : xmemdup (tz, tzsize));
1134 /* Parse a date/time string, storing the resulting time value into *RESULT.
1135 The string itself is pointed to by P. Return true if successful.
1136 P can be an incomplete or relative time specification; if so, use
1137 *NOW as the basis for the returned time. */
1139 get_date (struct timespec *result, char const *p, struct timespec const *now)
1143 struct tm const *tmp;
1147 struct timespec gettime_buffer;
1149 bool tz_was_altered = false;
1151 char tz0buf[TZBUFSIZE];
1156 gettime (&gettime_buffer);
1157 now = &gettime_buffer;
1160 Start = now->tv_sec;
1161 Start_ns = now->tv_nsec;
1163 tmp = localtime (&now->tv_sec);
1167 while (c = *p, ISSPACE (c))
1170 if (strncmp (p, "TZ=\"", 4) == 0)
1172 char const *tzbase = p + 4;
1176 for (s = tzbase; *s; s++, tzsize++)
1180 if (! (*s == '\\' || *s == '"'))
1187 char tz1buf[TZBUFSIZE];
1188 bool large_tz = TZBUFSIZE < tzsize;
1190 tz0 = get_tz (tz0buf);
1191 z = tz1 = large_tz ? xmalloc (tzsize) : tz1buf;
1192 for (s = tzbase; *s != '"'; s++)
1193 *z++ = *(s += *s == '\\');
1195 setenv_ok = setenv ("TZ", tz1, 1) == 0;
1200 tz_was_altered = true;
1206 pc.year.value = tmp->tm_year;
1207 pc.year.value += TM_YEAR_BASE;
1209 pc.month = tmp->tm_mon + 1;
1210 pc.day = tmp->tm_mday;
1211 pc.hour = tmp->tm_hour;
1212 pc.minutes = tmp->tm_min;
1213 pc.seconds.tv_sec = tmp->tm_sec;
1214 pc.seconds.tv_nsec = Start_ns;
1215 tm.tm_isdst = tmp->tm_isdst;
1217 pc.meridian = MER24;
1225 pc.timespec_seen = false;
1226 pc.rels_seen = false;
1230 pc.local_zones_seen = 0;
1234 #if HAVE_STRUCT_TM_TM_ZONE
1235 pc.local_time_zone_table[0].name = tmp->tm_zone;
1236 pc.local_time_zone_table[0].type = tLOCAL_ZONE;
1237 pc.local_time_zone_table[0].value = tmp->tm_isdst;
1238 pc.local_time_zone_table[1].name = NULL;
1240 /* Probe the names used in the next three calendar quarters, looking
1241 for a tm_isdst different from the one we already have. */
1244 for (quarter = 1; quarter <= 3; quarter++)
1246 time_t probe = Start + quarter * (90 * 24 * 60 * 60);
1247 struct tm const *probe_tm = localtime (&probe);
1248 if (probe_tm && probe_tm->tm_zone
1249 && probe_tm->tm_isdst != pc.local_time_zone_table[0].value)
1252 pc.local_time_zone_table[1].name = probe_tm->tm_zone;
1253 pc.local_time_zone_table[1].type = tLOCAL_ZONE;
1254 pc.local_time_zone_table[1].value = probe_tm->tm_isdst;
1255 pc.local_time_zone_table[2].name = NULL;
1265 extern char *tzname[];
1268 for (i = 0; i < 2; i++)
1270 pc.local_time_zone_table[i].name = tzname[i];
1271 pc.local_time_zone_table[i].type = tLOCAL_ZONE;
1272 pc.local_time_zone_table[i].value = i;
1274 pc.local_time_zone_table[i].name = NULL;
1277 pc.local_time_zone_table[0].name = NULL;
1281 if (pc.local_time_zone_table[0].name && pc.local_time_zone_table[1].name
1282 && ! strcmp (pc.local_time_zone_table[0].name,
1283 pc.local_time_zone_table[1].name))
1285 /* This locale uses the same abbrevation for standard and
1286 daylight times. So if we see that abbreviation, we don't
1287 know whether it's daylight time. */
1288 pc.local_time_zone_table[0].value = -1;
1289 pc.local_time_zone_table[1].name = NULL;
1292 if (yyparse (&pc) != 0)
1295 if (pc.timespec_seen)
1296 *result = pc.seconds;
1299 if (1 < (pc.times_seen | pc.dates_seen | pc.days_seen | pc.dsts_seen
1300 | (pc.local_zones_seen + pc.zones_seen)))
1303 tm.tm_year = to_year (pc.year) - TM_YEAR_BASE;
1304 tm.tm_mon = pc.month - 1;
1305 tm.tm_mday = pc.day;
1306 if (pc.times_seen || (pc.rels_seen && ! pc.dates_seen && ! pc.days_seen))
1308 tm.tm_hour = to_hour (pc.hour, pc.meridian);
1311 tm.tm_min = pc.minutes;
1312 tm.tm_sec = pc.seconds.tv_sec;
1316 tm.tm_hour = tm.tm_min = tm.tm_sec = 0;
1317 pc.seconds.tv_nsec = 0;
1320 /* Let mktime deduce tm_isdst if we have an absolute time stamp. */
1324 /* But if the input explicitly specifies local time with or without
1325 DST, give mktime that information. */
1326 if (pc.local_zones_seen)
1327 tm.tm_isdst = pc.local_isdst;
1331 Start = mktime (&tm);
1333 if (! mktime_ok (&tm0, &tm, Start))
1335 if (! pc.zones_seen)
1339 /* Guard against falsely reporting errors near the time_t
1340 boundaries when parsing times in other time zones. For
1341 example, suppose the input string "1969-12-31 23:00:00 -0100",
1342 the current time zone is 8 hours ahead of UTC, and the min
1343 time_t value is 1970-01-01 00:00:00 UTC. Then the min
1344 localtime value is 1970-01-01 08:00:00, and mktime will
1345 therefore fail on 1969-12-31 23:00:00. To work around the
1346 problem, set the time zone to 1 hour behind UTC temporarily
1347 by setting TZ="XXX1:00" and try mktime again. */
1349 long int time_zone = pc.time_zone;
1350 long int abs_time_zone = time_zone < 0 ? - time_zone : time_zone;
1351 long int abs_time_zone_hour = abs_time_zone / 60;
1352 int abs_time_zone_min = abs_time_zone % 60;
1353 char tz1buf[sizeof "XXX+0:00"
1354 + sizeof pc.time_zone * CHAR_BIT / 3];
1355 if (!tz_was_altered)
1356 tz0 = get_tz (tz0buf);
1357 sprintf (tz1buf, "XXX%s%ld:%02d", "-" + (time_zone < 0),
1358 abs_time_zone_hour, abs_time_zone_min);
1359 if (setenv ("TZ", tz1buf, 1) != 0)
1361 tz_was_altered = true;
1363 Start = mktime (&tm);
1364 if (! mktime_ok (&tm0, &tm, Start))
1369 if (pc.days_seen && ! pc.dates_seen)
1371 tm.tm_mday += ((pc.day_number - tm.tm_wday + 7) % 7
1372 + 7 * (pc.day_ordinal - (0 < pc.day_ordinal)));
1374 Start = mktime (&tm);
1375 if (Start == (time_t) -1)
1381 long int delta = pc.time_zone * 60;
1383 #ifdef HAVE_TM_GMTOFF
1384 delta -= tm.tm_gmtoff;
1387 struct tm const *gmt = gmtime (&t);
1390 delta -= tm_diff (&tm, gmt);
1393 if ((Start < t1) != (delta < 0))
1394 goto fail; /* time_t overflow */
1398 /* Add relative date. */
1399 if (pc.rel_year | pc.rel_month | pc.rel_day)
1401 int year = tm.tm_year + pc.rel_year;
1402 int month = tm.tm_mon + pc.rel_month;
1403 int day = tm.tm_mday + pc.rel_day;
1404 if (((year < tm.tm_year) ^ (pc.rel_year < 0))
1405 | ((month < tm.tm_mon) ^ (pc.rel_month < 0))
1406 | ((day < tm.tm_mday) ^ (pc.rel_day < 0)))
1411 Start = mktime (&tm);
1412 if (Start == (time_t) -1)
1416 /* Add relative hours, minutes, and seconds. On hosts that support
1417 leap seconds, ignore the possibility of leap seconds; e.g.,
1418 "+ 10 minutes" adds 600 seconds, even if one of them is a
1419 leap second. Typically this is not what the user wants, but it's
1420 too hard to do it the other way, because the time zone indicator
1421 must be applied before relative times, and if mktime is applied
1422 again the time zone will be lost. */
1424 long int sum_ns = pc.seconds.tv_nsec + pc.rel_ns;
1425 long int normalized_ns = (sum_ns % BILLION + BILLION) % BILLION;
1427 long int d1 = 60 * 60 * pc.rel_hour;
1428 time_t t1 = t0 + d1;
1429 long int d2 = 60 * pc.rel_minutes;
1430 time_t t2 = t1 + d2;
1431 long int d3 = pc.rel_seconds;
1432 time_t t3 = t2 + d3;
1433 long int d4 = (sum_ns - normalized_ns) / BILLION;
1434 time_t t4 = t3 + d4;
1436 if ((d1 / (60 * 60) ^ pc.rel_hour)
1437 | (d2 / 60 ^ pc.rel_minutes)
1438 | ((t1 < t0) ^ (d1 < 0))
1439 | ((t2 < t1) ^ (d2 < 0))
1440 | ((t3 < t2) ^ (d3 < 0))
1441 | ((t4 < t3) ^ (d4 < 0)))
1444 result->tv_sec = t4;
1445 result->tv_nsec = normalized_ns;
1455 ok &= (tz0 ? setenv ("TZ", tz0, 1) : unsetenv ("TZ")) == 0;
1464 main (int ac, char **av)
1468 printf ("Enter date, or blank line to exit.\n\t> ");
1471 buff[BUFSIZ - 1] = '\0';
1472 while (fgets (buff, BUFSIZ - 1, stdin) && buff[0])
1475 struct tm const *tm;
1476 if (! get_date (&d, buff, NULL))
1477 printf ("Bad format - couldn't convert.\n");
1478 else if (! (tm = localtime (&d.tv_sec)))
1480 long int sec = d.tv_sec;
1481 printf ("localtime (%ld) failed\n", sec);
1486 printf ("%04ld-%02d-%02d %02d:%02d:%02d.%09d\n",
1487 tm->tm_year + 1900L, tm->tm_mon + 1, tm->tm_mday,
1488 tm->tm_hour, tm->tm_min, tm->tm_sec, ns);