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Diffstat (limited to 'lib/getdate.y')
| -rw-r--r-- | lib/getdate.y | 1520 |
1 files changed, 1520 insertions, 0 deletions
diff --git a/lib/getdate.y b/lib/getdate.y new file mode 100644 index 0000000..cbf3ca1 --- /dev/null +++ b/lib/getdate.y @@ -0,0 +1,1520 @@ +%{ +/* Parse a string into an internal time stamp. + + Copyright (C) 1999, 2000, 2002, 2003, 2004, 2005, 2006, 2007 Free Software + Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software Foundation, + Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ + +/* Originally written by Steven M. Bellovin <smb@research.att.com> while + at the University of North Carolina at Chapel Hill. Later tweaked by + a couple of people on Usenet. Completely overhauled by Rich $alz + <rsalz@bbn.com> and Jim Berets <jberets@bbn.com> in August, 1990. + + Modified by Paul Eggert <eggert@twinsun.com> in August 1999 to do + the right thing about local DST. Also modified by Paul Eggert + <eggert@cs.ucla.edu> in February 2004 to support + nanosecond-resolution time stamps, and in October 2004 to support + TZ strings in dates. */ + +/* FIXME: Check for arithmetic overflow in all cases, not just + some of them. */ + +#include <config.h> + +#include "getdate.h" +#include "timespec.h" + +/* There's no need to extend the stack, so there's no need to involve + alloca. */ +#define YYSTACK_USE_ALLOCA 0 + +/* Tell Bison how much stack space is needed. 20 should be plenty for + this grammar, which is not right recursive. Beware setting it too + high, since that might cause problems on machines whose + implementations have lame stack-overflow checking. */ +#define YYMAXDEPTH 20 +#define YYINITDEPTH YYMAXDEPTH + +/* Since the code of getdate.y is not included in the Emacs executable + itself, there is no need to #define static in this file. Even if + the code were included in the Emacs executable, it probably + wouldn't do any harm to #undef it here; this will only cause + problems if we try to write to a static variable, which I don't + think this code needs to do. */ +#ifdef emacs +# undef static +#endif + +#include <ctype.h> +#include <limits.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "setenv.h" +#include "xalloc.h" + + +/* ISDIGIT differs from isdigit, as follows: + - Its arg may be any int or unsigned int; it need not be an unsigned char + or EOF. + - It's typically faster. + POSIX says that only '0' through '9' are digits. Prefer ISDIGIT to + isdigit unless it's important to use the locale's definition + of `digit' even when the host does not conform to POSIX. */ +#define ISDIGIT(c) ((unsigned int) (c) - '0' <= 9) + +#ifndef __attribute__ +# if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8) || __STRICT_ANSI__ +# define __attribute__(x) +# endif +#endif + +#ifndef ATTRIBUTE_UNUSED +# define ATTRIBUTE_UNUSED __attribute__ ((__unused__)) +#endif + +/* Shift A right by B bits portably, by dividing A by 2**B and + truncating towards minus infinity. A and B should be free of side + effects, and B should be in the range 0 <= B <= INT_BITS - 2, where + INT_BITS is the number of useful bits in an int. GNU code can + assume that INT_BITS is at least 32. + + ISO C99 says that A >> B is implementation-defined if A < 0. Some + implementations (e.g., UNICOS 9.0 on a Cray Y-MP EL) don't shift + right in the usual way when A < 0, so SHR falls back on division if + ordinary A >> B doesn't seem to be the usual signed shift. */ +#define SHR(a, b) \ + (-1 >> 1 == -1 \ + ? (a) >> (b) \ + : (a) / (1 << (b)) - ((a) % (1 << (b)) < 0)) + +#define EPOCH_YEAR 1970 +#define TM_YEAR_BASE 1900 + +#define HOUR(x) ((x) * 60) + +/* An integer value, and the number of digits in its textual + representation. */ +typedef struct +{ + bool negative; + long int value; + size_t digits; +} textint; + +/* An entry in the lexical lookup table. */ +typedef struct +{ + char const *name; + int type; + int value; +} table; + +/* Meridian: am, pm, or 24-hour style. */ +enum { MERam, MERpm, MER24 }; + +enum { BILLION = 1000000000, LOG10_BILLION = 9 }; + +/* Relative times. */ +typedef struct +{ + /* Relative year, month, day, hour, minutes, seconds, and nanoseconds. */ + long int year; + long int month; + long int day; + long int hour; + long int minutes; + long int seconds; + long int ns; +} relative_time; + +#if HAVE_COMPOUND_LITERALS +# define RELATIVE_TIME_0 ((relative_time) { 0, 0, 0, 0, 0, 0, 0 }) +#else +static relative_time const RELATIVE_TIME_0; +#endif + +/* Information passed to and from the parser. */ +typedef struct +{ + /* The input string remaining to be parsed. */ + const char *input; + + /* N, if this is the Nth Tuesday. */ + long int day_ordinal; + + /* Day of week; Sunday is 0. */ + int day_number; + + /* tm_isdst flag for the local zone. */ + int local_isdst; + + /* Time zone, in minutes east of UTC. */ + long int time_zone; + + /* Style used for time. */ + int meridian; + + /* Gregorian year, month, day, hour, minutes, seconds, and nanoseconds. */ + textint year; + long int month; + long int day; + long int hour; + long int minutes; + struct timespec seconds; /* includes nanoseconds */ + + /* Relative year, month, day, hour, minutes, seconds, and nanoseconds. */ + relative_time rel; + + /* Presence or counts of nonterminals of various flavors parsed so far. */ + bool timespec_seen; + bool rels_seen; + size_t dates_seen; + size_t days_seen; + size_t local_zones_seen; + size_t dsts_seen; + size_t times_seen; + size_t zones_seen; + + /* Table of local time zone abbrevations, terminated by a null entry. */ + table local_time_zone_table[3]; +} parser_control; + +union YYSTYPE; +static int yylex (union YYSTYPE *, parser_control *); +static int yyerror (parser_control const *, char const *); +static long int time_zone_hhmm (textint, long int); + +%} + +/* We want a reentrant parser, even if the TZ manipulation and the calls to + localtime and gmtime are not reentrant. */ +%pure-parser +%parse-param { parser_control *pc } +%lex-param { parser_control *pc } + +/* This grammar has 20 shift/reduce conflicts. */ +%expect 20 + +%union +{ + long int intval; + textint textintval; + struct timespec timespec; + relative_time rel; +} + +%token tAGO tDST + +%token tYEAR_UNIT tMONTH_UNIT tHOUR_UNIT tMINUTE_UNIT tSEC_UNIT +%token <intval> tDAY_UNIT + +%token <intval> tDAY tDAYZONE tLOCAL_ZONE tMERIDIAN +%token <intval> tMONTH tORDINAL tZONE + +%token <textintval> tSNUMBER tUNUMBER +%token <timespec> tSDECIMAL_NUMBER tUDECIMAL_NUMBER + +%type <intval> o_colon_minutes o_merid +%type <timespec> seconds signed_seconds unsigned_seconds + +%type <rel> relunit relunit_snumber + +%% + +spec: + timespec + | items + ; + +timespec: + '@' seconds + { + pc->seconds = $2; + pc->timespec_seen = true; + } + ; + +items: + /* empty */ + | items item + ; + +item: + time + { pc->times_seen++; } + | local_zone + { pc->local_zones_seen++; } + | zone + { pc->zones_seen++; } + | date + { pc->dates_seen++; } + | day + { pc->days_seen++; } + | rel + { pc->rels_seen = true; } + | number + ; + +time: + tUNUMBER tMERIDIAN + { + pc->hour = $1.value; + pc->minutes = 0; + pc->seconds.tv_sec = 0; + pc->seconds.tv_nsec = 0; + pc->meridian = $2; + } + | tUNUMBER ':' tUNUMBER o_merid + { + pc->hour = $1.value; + pc->minutes = $3.value; + pc->seconds.tv_sec = 0; + pc->seconds.tv_nsec = 0; + pc->meridian = $4; + } + | tUNUMBER ':' tUNUMBER tSNUMBER o_colon_minutes + { + pc->hour = $1.value; + pc->minutes = $3.value; + pc->seconds.tv_sec = 0; + pc->seconds.tv_nsec = 0; + pc->meridian = MER24; + pc->zones_seen++; + pc->time_zone = time_zone_hhmm ($4, $5); + } + | tUNUMBER ':' tUNUMBER ':' unsigned_seconds o_merid + { + pc->hour = $1.value; + pc->minutes = $3.value; + pc->seconds = $5; + pc->meridian = $6; + } + | tUNUMBER ':' tUNUMBER ':' unsigned_seconds tSNUMBER o_colon_minutes + { + pc->hour = $1.value; + pc->minutes = $3.value; + pc->seconds = $5; + pc->meridian = MER24; + pc->zones_seen++; + pc->time_zone = time_zone_hhmm ($6, $7); + } + ; + +local_zone: + tLOCAL_ZONE + { + pc->local_isdst = $1; + pc->dsts_seen += (0 < $1); + } + | tLOCAL_ZONE tDST + { + pc->local_isdst = 1; + pc->dsts_seen += (0 < $1) + 1; + } + ; + +zone: + tZONE + { pc->time_zone = $1; } + | tZONE relunit_snumber + { pc->time_zone = $1; + pc->rel.ns += $2.ns; + pc->rel.seconds += $2.seconds; + pc->rel.minutes += $2.minutes; + pc->rel.hour += $2.hour; + pc->rel.day += $2.day; + pc->rel.month += $2.month; + pc->rel.year += $2.year; + pc->rels_seen = true; } + | tZONE tSNUMBER o_colon_minutes + { pc->time_zone = $1 + time_zone_hhmm ($2, $3); } + | tDAYZONE + { pc->time_zone = $1 + 60; } + | tZONE tDST + { pc->time_zone = $1 + 60; } + ; + +day: + tDAY + { + pc->day_ordinal = 1; + pc->day_number = $1; + } + | tDAY ',' + { + pc->day_ordinal = 1; + pc->day_number = $1; + } + | tORDINAL tDAY + { + pc->day_ordinal = $1; + pc->day_number = $2; + } + | tUNUMBER tDAY + { + pc->day_ordinal = $1.value; + pc->day_number = $2; + } + ; + +date: + tUNUMBER '/' tUNUMBER + { + pc->month = $1.value; + pc->day = $3.value; + } + | tUNUMBER '/' tUNUMBER '/' tUNUMBER + { + /* Interpret as YYYY/MM/DD if the first value has 4 or more digits, + otherwise as MM/DD/YY. + The goal in recognizing YYYY/MM/DD is solely to support legacy + machine-generated dates like those in an RCS log listing. If + you want portability, use the ISO 8601 format. */ + if (4 <= $1.digits) + { + pc->year = $1; + pc->month = $3.value; + pc->day = $5.value; + } + else + { + pc->month = $1.value; + pc->day = $3.value; + pc->year = $5; + } + } + | tUNUMBER tSNUMBER tSNUMBER + { + /* ISO 8601 format. YYYY-MM-DD. */ + pc->year = $1; + pc->month = -$2.value; + pc->day = -$3.value; + } + | tUNUMBER tMONTH tSNUMBER + { + /* e.g. 17-JUN-1992. */ + pc->day = $1.value; + pc->month = $2; + pc->year.value = -$3.value; + pc->year.digits = $3.digits; + } + | tMONTH tSNUMBER tSNUMBER + { + /* e.g. JUN-17-1992. */ + pc->month = $1; + pc->day = -$2.value; + pc->year.value = -$3.value; + pc->year.digits = $3.digits; + } + | tMONTH tUNUMBER + { + pc->month = $1; + pc->day = $2.value; + } + | tMONTH tUNUMBER ',' tUNUMBER + { + pc->month = $1; + pc->day = $2.value; + pc->year = $4; + } + | tUNUMBER tMONTH + { + pc->day = $1.value; + pc->month = $2; + } + | tUNUMBER tMONTH tUNUMBER + { + pc->day = $1.value; + pc->month = $2; + pc->year = $3; + } + ; + +rel: + relunit tAGO + { + pc->rel.ns -= $1.ns; + pc->rel.seconds -= $1.seconds; + pc->rel.minutes -= $1.minutes; + pc->rel.hour -= $1.hour; + pc->rel.day -= $1.day; + pc->rel.month -= $1.month; + pc->rel.year -= $1.year; + } + | relunit + { + pc->rel.ns += $1.ns; + pc->rel.seconds += $1.seconds; + pc->rel.minutes += $1.minutes; + pc->rel.hour += $1.hour; + pc->rel.day += $1.day; + pc->rel.month += $1.month; + pc->rel.year += $1.year; + } + ; + +relunit: + tORDINAL tYEAR_UNIT + { $$ = RELATIVE_TIME_0; $$.year = $1; } + | tUNUMBER tYEAR_UNIT + { $$ = RELATIVE_TIME_0; $$.year = $1.value; } + | tYEAR_UNIT + { $$ = RELATIVE_TIME_0; $$.year = 1; } + | tORDINAL tMONTH_UNIT + { $$ = RELATIVE_TIME_0; $$.month = $1; } + | tUNUMBER tMONTH_UNIT + { $$ = RELATIVE_TIME_0; $$.month = $1.value; } + | tMONTH_UNIT + { $$ = RELATIVE_TIME_0; $$.month = 1; } + | tORDINAL tDAY_UNIT + { $$ = RELATIVE_TIME_0; $$.day = $1 * $2; } + | tUNUMBER tDAY_UNIT + { $$ = RELATIVE_TIME_0; $$.day = $1.value * $2; } + | tDAY_UNIT + { $$ = RELATIVE_TIME_0; $$.day = $1; } + | tORDINAL tHOUR_UNIT + { $$ = RELATIVE_TIME_0; $$.hour = $1; } + | tUNUMBER tHOUR_UNIT + { $$ = RELATIVE_TIME_0; $$.hour = $1.value; } + | tHOUR_UNIT + { $$ = RELATIVE_TIME_0; $$.hour = 1; } + | tORDINAL tMINUTE_UNIT + { $$ = RELATIVE_TIME_0; $$.minutes = $1; } + | tUNUMBER tMINUTE_UNIT + { $$ = RELATIVE_TIME_0; $$.minutes = $1.value; } + | tMINUTE_UNIT + { $$ = RELATIVE_TIME_0; $$.minutes = 1; } + | tORDINAL tSEC_UNIT + { $$ = RELATIVE_TIME_0; $$.seconds = $1; } + | tUNUMBER tSEC_UNIT + { $$ = RELATIVE_TIME_0; $$.seconds = $1.value; } + | tSDECIMAL_NUMBER tSEC_UNIT + { $$ = RELATIVE_TIME_0; $$.seconds = $1.tv_sec; $$.ns = $1.tv_nsec; } + | tUDECIMAL_NUMBER tSEC_UNIT + { $$ = RELATIVE_TIME_0; $$.seconds = $1.tv_sec; $$.ns = $1.tv_nsec; } + | tSEC_UNIT + { $$ = RELATIVE_TIME_0; $$.seconds = 1; } + | relunit_snumber + ; + +relunit_snumber: + tSNUMBER tYEAR_UNIT + { $$ = RELATIVE_TIME_0; $$.year = $1.value; } + | tSNUMBER tMONTH_UNIT + { $$ = RELATIVE_TIME_0; $$.month = $1.value; } + | tSNUMBER tDAY_UNIT + { $$ = RELATIVE_TIME_0; $$.day = $1.value * $2; } + | tSNUMBER tHOUR_UNIT + { $$ = RELATIVE_TIME_0; $$.hour = $1.value; } + | tSNUMBER tMINUTE_UNIT + { $$ = RELATIVE_TIME_0; $$.minutes = $1.value; } + | tSNUMBER tSEC_UNIT + { $$ = RELATIVE_TIME_0; $$.seconds = $1.value; } + ; + +seconds: signed_seconds | unsigned_seconds; + +signed_seconds: + tSDECIMAL_NUMBER + | tSNUMBER + { $$.tv_sec = $1.value; $$.tv_nsec = 0; } + ; + +unsigned_seconds: + tUDECIMAL_NUMBER + | tUNUMBER + { $$.tv_sec = $1.value; $$.tv_nsec = 0; } + ; + +number: + tUNUMBER + { + if (pc->dates_seen && ! pc->year.digits + && ! pc->rels_seen && (pc->times_seen || 2 < $1.digits)) + pc->year = $1; + else + { + if (4 < $1.digits) + { + pc->dates_seen++; + pc->day = $1.value % 100; + pc->month = ($1.value / 100) % 100; + pc->year.value = $1.value / 10000; + pc->year.digits = $1.digits - 4; + } + else + { + pc->times_seen++; + if ($1.digits <= 2) + { + pc->hour = $1.value; + pc->minutes = 0; + } + else + { + pc->hour = $1.value / 100; + pc->minutes = $1.value % 100; + } + pc->seconds.tv_sec = 0; + pc->seconds.tv_nsec = 0; + pc->meridian = MER24; + } + } + } + ; + +o_colon_minutes: + /* empty */ + { $$ = -1; } + | ':' tUNUMBER + { $$ = $2.value; } + ; + +o_merid: + /* empty */ + { $$ = MER24; } + | tMERIDIAN + { $$ = $1; } + ; + +%% + +static table const meridian_table[] = +{ + { "AM", tMERIDIAN, MERam }, + { "A.M.", tMERIDIAN, MERam }, + { "PM", tMERIDIAN, MERpm }, + { "P.M.", tMERIDIAN, MERpm }, + { NULL, 0, 0 } +}; + +static table const dst_table[] = +{ + { "DST", tDST, 0 } +}; + +static table const month_and_day_table[] = +{ + { "JANUARY", tMONTH, 1 }, + { "FEBRUARY", tMONTH, 2 }, + { "MARCH", tMONTH, 3 }, + { "APRIL", tMONTH, 4 }, + { "MAY", tMONTH, 5 }, + { "JUNE", tMONTH, 6 }, + { "JULY", tMONTH, 7 }, + { "AUGUST", tMONTH, 8 }, + { "SEPTEMBER",tMONTH, 9 }, + { "SEPT", tMONTH, 9 }, + { "OCTOBER", tMONTH, 10 }, + { "NOVEMBER", tMONTH, 11 }, + { "DECEMBER", tMONTH, 12 }, + { "SUNDAY", tDAY, 0 }, + { "MONDAY", tDAY, 1 }, + { "TUESDAY", tDAY, 2 }, + { "TUES", tDAY, 2 }, + { "WEDNESDAY",tDAY, 3 }, + { "WEDNES", tDAY, 3 }, + { "THURSDAY", tDAY, 4 }, + { "THUR", tDAY, 4 }, + { "THURS", tDAY, 4 }, + { "FRIDAY", tDAY, 5 }, + { "SATURDAY", tDAY, 6 }, + { NULL, 0, 0 } +}; + +static table const time_units_table[] = +{ + { "YEAR", tYEAR_UNIT, 1 }, + { "MONTH", tMONTH_UNIT, 1 }, + { "FORTNIGHT",tDAY_UNIT, 14 }, + { "WEEK", tDAY_UNIT, 7 }, + { "DAY", tDAY_UNIT, 1 }, + { "HOUR", tHOUR_UNIT, 1 }, + { "MINUTE", tMINUTE_UNIT, 1 }, + { "MIN", tMINUTE_UNIT, 1 }, + { "SECOND", tSEC_UNIT, 1 }, + { "SEC", tSEC_UNIT, 1 }, + { NULL, 0, 0 } +}; + +/* Assorted relative-time words. */ +static table const relative_time_table[] = +{ + { "TOMORROW", tDAY_UNIT, 1 }, + { "YESTERDAY",tDAY_UNIT, -1 }, + { "TODAY", tDAY_UNIT, 0 }, + { "NOW", tDAY_UNIT, 0 }, + { "LAST", tORDINAL, -1 }, + { "THIS", tORDINAL, 0 }, + { "NEXT", tORDINAL, 1 }, + { "FIRST", tORDINAL, 1 }, +/*{ "SECOND", tORDINAL, 2 }, */ + { "THIRD", tORDINAL, 3 }, + { "FOURTH", tORDINAL, 4 }, + { "FIFTH", tORDINAL, 5 }, + { "SIXTH", tORDINAL, 6 }, + { "SEVENTH", tORDINAL, 7 }, + { "EIGHTH", tORDINAL, 8 }, + { "NINTH", tORDINAL, 9 }, + { "TENTH", tORDINAL, 10 }, + { "ELEVENTH", tORDINAL, 11 }, + { "TWELFTH", tORDINAL, 12 }, + { "AGO", tAGO, 1 }, + { NULL, 0, 0 } +}; + +/* The universal time zone table. These labels can be used even for + time stamps that would not otherwise be valid, e.g., GMT time + stamps in London during summer. */ +static table const universal_time_zone_table[] = +{ + { "GMT", tZONE, HOUR ( 0) }, /* Greenwich Mean */ + { "UT", tZONE, HOUR ( 0) }, /* Universal (Coordinated) */ + { "UTC", tZONE, HOUR ( 0) }, + { NULL, 0, 0 } +}; + +/* The time zone table. This table is necessarily incomplete, as time + zone abbreviations are ambiguous; e.g. Australians interpret "EST" + as Eastern time in Australia, not as US Eastern Standard Time. + You cannot rely on getdate to handle arbitrary time zone + abbreviations; use numeric abbreviations like `-0500' instead. */ +static table const time_zone_table[] = +{ + { "WET", tZONE, HOUR ( 0) }, /* Western European */ + { "WEST", tDAYZONE, HOUR ( 0) }, /* Western European Summer */ + { "BST", tDAYZONE, HOUR ( 0) }, /* British Summer */ + { "ART", tZONE, -HOUR ( 3) }, /* Argentina */ + { "BRT", tZONE, -HOUR ( 3) }, /* Brazil */ + { "BRST", tDAYZONE, -HOUR ( 3) }, /* Brazil Summer */ + { "NST", tZONE, -(HOUR ( 3) + 30) }, /* Newfoundland Standard */ + { "NDT", tDAYZONE,-(HOUR ( 3) + 30) }, /* Newfoundland Daylight */ + { "AST", tZONE, -HOUR ( 4) }, /* Atlantic Standard */ + { "ADT", tDAYZONE, -HOUR ( 4) }, /* Atlantic Daylight */ + { "CLT", tZONE, -HOUR ( 4) }, /* Chile */ + { "CLST", tDAYZONE, -HOUR ( 4) }, /* Chile Summer */ + { "EST", tZONE, -HOUR ( 5) }, /* Eastern Standard */ + { "EDT", tDAYZONE, -HOUR ( 5) }, /* Eastern Daylight */ + { "CST", tZONE, -HOUR ( 6) }, /* Central Standard */ + { "CDT", tDAYZONE, -HOUR ( 6) }, /* Central Daylight */ + { "MST", tZONE, -HOUR ( 7) }, /* Mountain Standard */ + { "MDT", tDAYZONE, -HOUR ( 7) }, /* Mountain Daylight */ + { "PST", tZONE, -HOUR ( 8) }, /* Pacific Standard */ + { "PDT", tDAYZONE, -HOUR ( 8) }, /* Pacific Daylight */ + { "AKST", tZONE, -HOUR ( 9) }, /* Alaska Standard */ + { "AKDT", tDAYZONE, -HOUR ( 9) }, /* Alaska Daylight */ + { "HST", tZONE, -HOUR (10) }, /* Hawaii Standard */ + { "HAST", tZONE, -HOUR (10) }, /* Hawaii-Aleutian Standard */ + { "HADT", tDAYZONE, -HOUR (10) }, /* Hawaii-Aleutian Daylight */ + { "SST", tZONE, -HOUR (12) }, /* Samoa Standard */ + { "WAT", tZONE, HOUR ( 1) }, /* West Africa */ + { "CET", tZONE, HOUR ( 1) }, /* Central European */ + { "CEST", tDAYZONE, HOUR ( 1) }, /* Central European Summer */ + { "MET", tZONE, HOUR ( 1) }, /* Middle European */ + { "MEZ", tZONE, HOUR ( 1) }, /* Middle European */ + { "MEST", tDAYZONE, HOUR ( 1) }, /* Middle European Summer */ + { "MESZ", tDAYZONE, HOUR ( 1) }, /* Middle European Summer */ + { "EET", tZONE, HOUR ( 2) }, /* Eastern European */ + { "EEST", tDAYZONE, HOUR ( 2) }, /* Eastern European Summer */ + { "CAT", tZONE, HOUR ( 2) }, /* Central Africa */ + { "SAST", tZONE, HOUR ( 2) }, /* South Africa Standard */ + { "EAT", tZONE, HOUR ( 3) }, /* East Africa */ + { "MSK", tZONE, HOUR ( 3) }, /* Moscow */ + { "MSD", tDAYZONE, HOUR ( 3) }, /* Moscow Daylight */ + { "IST", tZONE, (HOUR ( 5) + 30) }, /* India Standard */ + { "SGT", tZONE, HOUR ( 8) }, /* Singapore */ + { "KST", tZONE, HOUR ( 9) }, /* Korea Standard */ + { "JST", tZONE, HOUR ( 9) }, /* Japan Standard */ + { "GST", tZONE, HOUR (10) }, /* Guam Standard */ + { "NZST", tZONE, HOUR (12) }, /* New Zealand Standard */ + { "NZDT", tDAYZONE, HOUR (12) }, /* New Zealand Daylight */ + { NULL, 0, 0 } +}; + +/* Military time zone table. */ +static table const military_table[] = +{ + { "A", tZONE, -HOUR ( 1) }, + { "B", tZONE, -HOUR ( 2) }, + { "C", tZONE, -HOUR ( 3) }, + { "D", tZONE, -HOUR ( 4) }, + { "E", tZONE, -HOUR ( 5) }, + { "F", tZONE, -HOUR ( 6) }, + { "G", tZONE, -HOUR ( 7) }, + { "H", tZONE, -HOUR ( 8) }, + { "I", tZONE, -HOUR ( 9) }, + { "K", tZONE, -HOUR (10) }, + { "L", tZONE, -HOUR (11) }, + { "M", tZONE, -HOUR (12) }, + { "N", tZONE, HOUR ( 1) }, + { "O", tZONE, HOUR ( 2) }, + { "P", tZONE, HOUR ( 3) }, + { "Q", tZONE, HOUR ( 4) }, + { "R", tZONE, HOUR ( 5) }, + { "S", tZONE, HOUR ( 6) }, + { "T", tZONE, HOUR ( 7) }, + { "U", tZONE, HOUR ( 8) }, + { "V", tZONE, HOUR ( 9) }, + { "W", tZONE, HOUR (10) }, + { "X", tZONE, HOUR (11) }, + { "Y", tZONE, HOUR (12) }, + { "Z", tZONE, HOUR ( 0) }, + { NULL, 0, 0 } +}; + + + +/* Convert a time zone expressed as HH:MM into an integer count of + minutes. If MM is negative, then S is of the form HHMM and needs + to be picked apart; otherwise, S is of the form HH. */ + +static long int +time_zone_hhmm (textint s, long int mm) +{ + if (mm < 0) + return (s.value / 100) * 60 + s.value % 100; + else + return s.value * 60 + (s.negative ? -mm : mm); +} + +static int +to_hour (long int hours, int meridian) +{ + switch (meridian) + { + default: /* Pacify GCC. */ + case MER24: + return 0 <= hours && hours < 24 ? hours : -1; + case MERam: + return 0 < hours && hours < 12 ? hours : hours == 12 ? 0 : -1; + case MERpm: + return 0 < hours && hours < 12 ? hours + 12 : hours == 12 ? 12 : -1; + } +} + +static long int +to_year (textint textyear) +{ + long int year = textyear.value; + + if (year < 0) + year = -year; + + /* XPG4 suggests that years 00-68 map to 2000-2068, and + years 69-99 map to 1969-1999. */ + else if (textyear.digits == 2) + year += year < 69 ? 2000 : 1900; + + return year; +} + +static table const * +lookup_zone (parser_control const *pc, char const *name) +{ + table const *tp; + + for (tp = universal_time_zone_table; tp->name; tp++) + if (strcmp (name, tp->name) == 0) + return tp; + + /* Try local zone abbreviations before those in time_zone_table, as + the local ones are more likely to be right. */ + for (tp = pc->local_time_zone_table; tp->name; tp++) + if (strcmp (name, tp->name) == 0) + return tp; + + for (tp = time_zone_table; tp->name; tp++) + if (strcmp (name, tp->name) == 0) + return tp; + + return NULL; +} + +#if ! HAVE_TM_GMTOFF +/* Yield the difference between *A and *B, + measured in seconds, ignoring leap seconds. + The body of this function is taken directly from the GNU C Library; + see src/strftime.c. */ +static long int +tm_diff (struct tm const *a, struct tm const *b) +{ + /* Compute intervening leap days correctly even if year is negative. + Take care to avoid int overflow in leap day calculations. */ + int a4 = SHR (a->tm_year, 2) + SHR (TM_YEAR_BASE, 2) - ! (a->tm_year & 3); + int b4 = SHR (b->tm_year, 2) + SHR (TM_YEAR_BASE, 2) - ! (b->tm_year & 3); + int a100 = a4 / 25 - (a4 % 25 < 0); + int b100 = b4 / 25 - (b4 % 25 < 0); + int a400 = SHR (a100, 2); + int b400 = SHR (b100, 2); + int intervening_leap_days = (a4 - b4) - (a100 - b100) + (a400 - b400); + long int ayear = a->tm_year; + long int years = ayear - b->tm_year; + long int days = (365 * years + intervening_leap_days + + (a->tm_yday - b->tm_yday)); + return (60 * (60 * (24 * days + (a->tm_hour - b->tm_hour)) + + (a->tm_min - b->tm_min)) + + (a->tm_sec - b->tm_sec)); +} +#endif /* ! HAVE_TM_GMTOFF */ + +static table const * +lookup_word (parser_control const *pc, char *word) +{ + char *p; + char *q; + size_t wordlen; + table const *tp; + bool period_found; + bool abbrev; + + /* Make it uppercase. */ + for (p = word; *p; p++) + { + unsigned char ch = *p; + *p = toupper (ch); + } + + for (tp = meridian_table; tp->name; tp++) + if (strcmp (word, tp->name) == 0) + return tp; + + /* See if we have an abbreviation for a month. */ + wordlen = strlen (word); + abbrev = wordlen == 3 || (wordlen == 4 && word[3] == '.'); + + for (tp = month_and_day_table; tp->name; tp++) + if ((abbrev ? strncmp (word, tp->name, 3) : strcmp (word, tp->name)) == 0) + return tp; + + if ((tp = lookup_zone (pc, word))) + return tp; + + if (strcmp (word, dst_table[0].name) == 0) + return dst_table; + + for (tp = time_units_table; tp->name; tp++) + if (strcmp (word, tp->name) == 0) + return tp; + + /* Strip off any plural and try the units table again. */ + if (word[wordlen - 1] == 'S') + { + word[wordlen - 1] = '\0'; + for (tp = time_units_table; tp->name; tp++) + if (strcmp (word, tp->name) == 0) + return tp; + word[wordlen - 1] = 'S'; /* For "this" in relative_time_table. */ + } + + for (tp = relative_time_table; tp->name; tp++) + if (strcmp (word, tp->name) == 0) + return tp; + + /* Military time zones. */ + if (wordlen == 1) + for (tp = military_table; tp->name; tp++) + if (word[0] == tp->name[0]) + return tp; + + /* Drop out any periods and try the time zone table again. */ + for (period_found = false, p = q = word; (*p = *q); q++) + if (*q == '.') + period_found = true; + else + p++; + if (period_found && (tp = lookup_zone (pc, word))) + return tp; + + return NULL; +} + +static int +yylex (YYSTYPE *lvalp, parser_control *pc) +{ + unsigned char c; + size_t count; + + for (;;) + { + while (c = *pc->input, isspace (c)) + pc->input++; + + if (ISDIGIT (c) || c == '-' || c == '+') + { + char const *p; + int sign; + unsigned long int value; + if (c == '-' || c == '+') + { + sign = c == '-' ? -1 : 1; + while (c = *++pc->input, isspace (c)) + continue; + if (! ISDIGIT (c)) + /* skip the '-' sign */ + continue; + } + else + sign = 0; + p = pc->input; + for (value = 0; ; value *= 10) + { + unsigned long int value1 = value + (c - '0'); + if (value1 < value) + return '?'; + value = value1; + c = *++p; + if (! ISDIGIT (c)) + break; + if (ULONG_MAX / 10 < value) + return '?'; + } + if ((c == '.' || c == ',') && ISDIGIT (p[1])) + { + time_t s; + int ns; + int digits; + unsigned long int value1; + + /* Check for overflow when converting value to time_t. */ + if (sign < 0) + { + s = - value; + if (0 < s) + return '?'; + value1 = -s; + } + else + { + s = value; + if (s < 0) + return '?'; + value1 = s; + } + if (value != value1) + return '?'; + + /* Accumulate fraction, to ns precision. */ + p++; + ns = *p++ - '0'; + for (digits = 2; digits <= LOG10_BILLION; digits++) + { + ns *= 10; + if (ISDIGIT (*p)) + ns += *p++ - '0'; + } + + /* Skip excess digits, truncating toward -Infinity. */ + if (sign < 0) + for (; ISDIGIT (*p); p++) + if (*p != '0') + { + ns++; + break; + } + while (ISDIGIT (*p)) + p++; + + /* Adjust to the timespec convention, which is that + tv_nsec is always a positive offset even if tv_sec is + negative. */ + if (sign < 0 && ns) + { + s--; + if (! (s < 0)) + return '?'; + ns = BILLION - ns; + } + + lvalp->timespec.tv_sec = s; + lvalp->timespec.tv_nsec = ns; + pc->input = p; + return sign ? tSDECIMAL_NUMBER : tUDECIMAL_NUMBER; + } + else + { + lvalp->textintval.negative = sign < 0; + if (sign < 0) + { + lvalp->textintval.value = - value; + if (0 < lvalp->textintval.value) + return '?'; + } + else + { + lvalp->textintval.value = value; + if (lvalp->textintval.value < 0) + return '?'; + } + lvalp->textintval.digits = p - pc->input; + pc->input = p; + return sign ? tSNUMBER : tUNUMBER; + } + } + + if (isalpha (c)) + { + char buff[20]; + char *p = buff; + table const *tp; + + do + { + if (p < buff + sizeof buff - 1) + *p++ = c; + c = *++pc->input; + } + while (isalpha (c) || c == '.'); + + *p = '\0'; + tp = lookup_word (pc, buff); + if (! tp) + return '?'; + lvalp->intval = tp->value; + return tp->type; + } + + if (c != '(') + return *pc->input++; + count = 0; + do + { + c = *pc->input++; + if (c == '\0') + return c; + if (c == '(') + count++; + else if (c == ')') + count--; + } + while (count != 0); + } +} + +/* Do nothing if the parser reports an error. */ +static int +yyerror (parser_control const *pc ATTRIBUTE_UNUSED, + char const *s ATTRIBUTE_UNUSED) +{ + return 0; +} + +/* If *TM0 is the old and *TM1 is the new value of a struct tm after + passing it to mktime, return true if it's OK that mktime returned T. + It's not OK if *TM0 has out-of-range members. */ + +static bool +mktime_ok (struct tm const *tm0, struct tm const *tm1, time_t t) +{ + if (t == (time_t) -1) + { + /* Guard against falsely reporting an error when parsing a time + stamp that happens to equal (time_t) -1, on a host that + supports such a time stamp. */ + tm1 = localtime (&t); + if (!tm1) + return false; + } + + return ! ((tm0->tm_sec ^ tm1->tm_sec) + | (tm0->tm_min ^ tm1->tm_min) + | (tm0->tm_hour ^ tm1->tm_hour) + | (tm0->tm_mday ^ tm1->tm_mday) + | (tm0->tm_mon ^ tm1->tm_mon) + | (tm0->tm_year ^ tm1->tm_year)); +} + +/* A reasonable upper bound for the size of ordinary TZ strings. + Use heap allocation if TZ's length exceeds this. */ +enum { TZBUFSIZE = 100 }; + +/* Return a copy of TZ, stored in TZBUF if it fits, and heap-allocated + otherwise. */ +static char * +get_tz (char tzbuf[TZBUFSIZE]) +{ + char *tz = getenv ("TZ"); + if (tz) + { + size_t tzsize = strlen (tz) + 1; + tz = (tzsize <= TZBUFSIZE + ? memcpy (tzbuf, tz, tzsize) + : xmemdup (tz, tzsize)); + } + return tz; +} + +/* Parse a date/time string, storing the resulting time value into *RESULT. + The string itself is pointed to by P. Return true if successful. + P can be an incomplete or relative time specification; if so, use + *NOW as the basis for the returned time. */ +bool +get_date (struct timespec *result, char const *p, struct timespec const *now) +{ + time_t Start; + long int Start_ns; + struct tm const *tmp; + struct tm tm; + struct tm tm0; + parser_control pc; + struct timespec gettime_buffer; + unsigned char c; + bool tz_was_altered = false; + char *tz0 = NULL; + char tz0buf[TZBUFSIZE]; + bool ok = true; + + if (! now) + { + gettime (&gettime_buffer); + now = &gettime_buffer; + } + + Start = now->tv_sec; + Start_ns = now->tv_nsec; + + tmp = localtime (&now->tv_sec); + if (! tmp) + return false; + + while (c = *p, isspace (c)) + p++; + + if (strncmp (p, "TZ=\"", 4) == 0) + { + char const *tzbase = p + 4; + size_t tzsize = 1; + char const *s; + + for (s = tzbase; *s; s++, tzsize++) + if (*s == '\\') + { + s++; + if (! (*s == '\\' || *s == '"')) + break; + } + else if (*s == '"') + { + char *z; + char *tz1; + char tz1buf[TZBUFSIZE]; + bool large_tz = TZBUFSIZE < tzsize; + bool setenv_ok; + tz0 = get_tz (tz0buf); + z = tz1 = large_tz ? xmalloc (tzsize) : tz1buf; + for (s = tzbase; *s != '"'; s++) + *z++ = *(s += *s == '\\'); + *z = '\0'; + setenv_ok = setenv ("TZ", tz1, 1) == 0; + if (large_tz) + free (tz1); + if (!setenv_ok) + goto fail; + tz_was_altered = true; + p = s + 1; + } + } + + pc.input = p; + pc.year.value = tmp->tm_year; + pc.year.value += TM_YEAR_BASE; + pc.year.digits = 0; + pc.month = tmp->tm_mon + 1; + pc.day = tmp->tm_mday; + pc.hour = tmp->tm_hour; + pc.minutes = tmp->tm_min; + pc.seconds.tv_sec = tmp->tm_sec; + pc.seconds.tv_nsec = Start_ns; + tm.tm_isdst = tmp->tm_isdst; + + pc.meridian = MER24; + pc.rel = RELATIVE_TIME_0; + pc.timespec_seen = false; + pc.rels_seen = false; + pc.dates_seen = 0; + pc.days_seen = 0; + pc.times_seen = 0; + pc.local_zones_seen = 0; + pc.dsts_seen = 0; + pc.zones_seen = 0; + +#if HAVE_STRUCT_TM_TM_ZONE + pc.local_time_zone_table[0].name = tmp->tm_zone; + pc.local_time_zone_table[0].type = tLOCAL_ZONE; + pc.local_time_zone_table[0].value = tmp->tm_isdst; + pc.local_time_zone_table[1].name = NULL; + + /* Probe the names used in the next three calendar quarters, looking + for a tm_isdst different from the one we already have. */ + { + int quarter; + for (quarter = 1; quarter <= 3; quarter++) + { + time_t probe = Start + quarter * (90 * 24 * 60 * 60); + struct tm const *probe_tm = localtime (&probe); + if (probe_tm && probe_tm->tm_zone + && probe_tm->tm_isdst != pc.local_time_zone_table[0].value) + { + { + pc.local_time_zone_table[1].name = probe_tm->tm_zone; + pc.local_time_zone_table[1].type = tLOCAL_ZONE; + pc.local_time_zone_table[1].value = probe_tm->tm_isdst; + pc.local_time_zone_table[2].name = NULL; + } + break; + } + } + } +#else +#if HAVE_TZNAME + { +# ifndef tzname + extern char *tzname[]; +# endif + int i; + for (i = 0; i < 2; i++) + { + pc.local_time_zone_table[i].name = tzname[i]; + pc.local_time_zone_table[i].type = tLOCAL_ZONE; + pc.local_time_zone_table[i].value = i; + } + pc.local_time_zone_table[i].name = NULL; + } +#else + pc.local_time_zone_table[0].name = NULL; +#endif +#endif + + if (pc.local_time_zone_table[0].name && pc.local_time_zone_table[1].name + && ! strcmp (pc.local_time_zone_table[0].name, + pc.local_time_zone_table[1].name)) + { + /* This locale uses the same abbrevation for standard and + daylight times. So if we see that abbreviation, we don't + know whether it's daylight time. */ + pc.local_time_zone_table[0].value = -1; + pc.local_time_zone_table[1].name = NULL; + } + + if (yyparse (&pc) != 0) + goto fail; + + if (pc.timespec_seen) + *result = pc.seconds; + else + { + if (1 < (pc.times_seen | pc.dates_seen | pc.days_seen | pc.dsts_seen + | (pc.local_zones_seen + pc.zones_seen))) + goto fail; + + tm.tm_year = to_year (pc.year) - TM_YEAR_BASE; + tm.tm_mon = pc.month - 1; + tm.tm_mday = pc.day; + if (pc.times_seen || (pc.rels_seen && ! pc.dates_seen && ! pc.days_seen)) + { + tm.tm_hour = to_hour (pc.hour, pc.meridian); + if (tm.tm_hour < 0) + goto fail; + tm.tm_min = pc.minutes; + tm.tm_sec = pc.seconds.tv_sec; + } + else + { + tm.tm_hour = tm.tm_min = tm.tm_sec = 0; + pc.seconds.tv_nsec = 0; + } + + /* Let mktime deduce tm_isdst if we have an absolute time stamp. */ + if (pc.dates_seen | pc.days_seen | pc.times_seen) + tm.tm_isdst = -1; + + /* But if the input explicitly specifies local time with or without + DST, give mktime that information. */ + if (pc.local_zones_seen) + tm.tm_isdst = pc.local_isdst; + + tm0 = tm; + + Start = mktime (&tm); + + if (! mktime_ok (&tm0, &tm, Start)) + { + if (! pc.zones_seen) + goto fail; + else + { + /* Guard against falsely reporting errors near the time_t + boundaries when parsing times in other time zones. For + example, suppose the input string "1969-12-31 23:00:00 -0100", + the current time zone is 8 hours ahead of UTC, and the min + time_t value is 1970-01-01 00:00:00 UTC. Then the min + localtime value is 1970-01-01 08:00:00, and mktime will + therefore fail on 1969-12-31 23:00:00. To work around the + problem, set the time zone to 1 hour behind UTC temporarily + by setting TZ="XXX1:00" and try mktime again. */ + + long int time_zone = pc.time_zone; + long int abs_time_zone = time_zone < 0 ? - time_zone : time_zone; + long int abs_time_zone_hour = abs_time_zone / 60; + int abs_time_zone_min = abs_time_zone % 60; + char tz1buf[sizeof "XXX+0:00" + + sizeof pc.time_zone * CHAR_BIT / 3]; + if (!tz_was_altered) + tz0 = get_tz (tz0buf); + sprintf (tz1buf, "XXX%s%ld:%02d", "-" + (time_zone < 0), + abs_time_zone_hour, abs_time_zone_min); + if (setenv ("TZ", tz1buf, 1) != 0) + goto fail; + tz_was_altered = true; + tm = tm0; + Start = mktime (&tm); + if (! mktime_ok (&tm0, &tm, Start)) + goto fail; + } + } + + if (pc.days_seen && ! pc.dates_seen) + { + tm.tm_mday += ((pc.day_number - tm.tm_wday + 7) % 7 + + 7 * (pc.day_ordinal - (0 < pc.day_ordinal))); + tm.tm_isdst = -1; + Start = mktime (&tm); + if (Start == (time_t) -1) + goto fail; + } + + if (pc.zones_seen) + { + long int delta = pc.time_zone * 60; + time_t t1; +#ifdef HAVE_TM_GMTOFF + delta -= tm.tm_gmtoff; +#else + time_t t = Start; + struct tm const *gmt = gmtime (&t); + if (! gmt) + goto fail; + delta -= tm_diff (&tm, gmt); +#endif + t1 = Start - delta; + if ((Start < t1) != (delta < 0)) + goto fail; /* time_t overflow */ + Start = t1; + } + + /* Add relative date. */ + if (pc.rel.year | pc.rel.month | pc.rel.day) + { + int year = tm.tm_year + pc.rel.year; + int month = tm.tm_mon + pc.rel.month; + int day = tm.tm_mday + pc.rel.day; + if (((year < tm.tm_year) ^ (pc.rel.year < 0)) + | ((month < tm.tm_mon) ^ (pc.rel.month < 0)) + | ((day < tm.tm_mday) ^ (pc.rel.day < 0))) + goto fail; + tm.tm_year = year; + tm.tm_mon = month; + tm.tm_mday = day; + tm.tm_hour = tm0.tm_hour; + tm.tm_min = tm0.tm_min; + tm.tm_sec = tm0.tm_sec; + tm.tm_isdst = tm0.tm_isdst; + Start = mktime (&tm); + if (Start == (time_t) -1) + goto fail; + } + + /* Add relative hours, minutes, and seconds. On hosts that support + leap seconds, ignore the possibility of leap seconds; e.g., + "+ 10 minutes" adds 600 seconds, even if one of them is a + leap second. Typically this is not what the user wants, but it's + too hard to do it the other way, because the time zone indicator + must be applied before relative times, and if mktime is applied + again the time zone will be lost. */ + { + long int sum_ns = pc.seconds.tv_nsec + pc.rel.ns; + long int normalized_ns = (sum_ns % BILLION + BILLION) % BILLION; + time_t t0 = Start; + long int d1 = 60 * 60 * pc.rel.hour; + time_t t1 = t0 + d1; + long int d2 = 60 * pc.rel.minutes; + time_t t2 = t1 + d2; + long int d3 = pc.rel.seconds; + time_t t3 = t2 + d3; + long int d4 = (sum_ns - normalized_ns) / BILLION; + time_t t4 = t3 + d4; + + if ((d1 / (60 * 60) ^ pc.rel.hour) + | (d2 / 60 ^ pc.rel.minutes) + | ((t1 < t0) ^ (d1 < 0)) + | ((t2 < t1) ^ (d2 < 0)) + | ((t3 < t2) ^ (d3 < 0)) + | ((t4 < t3) ^ (d4 < 0))) + goto fail; + + result->tv_sec = t4; + result->tv_nsec = normalized_ns; + } + } + + goto done; + + fail: + ok = false; + done: + if (tz_was_altered) + ok &= (tz0 ? setenv ("TZ", tz0, 1) : unsetenv ("TZ")) == 0; + if (tz0 != tz0buf) + free (tz0); + return ok; +} + +#if TEST + +int +main (int ac, char **av) +{ + char buff[BUFSIZ]; + + printf ("Enter date, or blank line to exit.\n\t> "); + fflush (stdout); + + buff[BUFSIZ - 1] = '\0'; + while (fgets (buff, BUFSIZ - 1, stdin) && buff[0]) + { + struct timespec d; + struct tm const *tm; + if (! get_date (&d, buff, NULL)) + printf ("Bad format - couldn't convert.\n"); + else if (! (tm = localtime (&d.tv_sec))) + { + long int sec = d.tv_sec; + printf ("localtime (%ld) failed\n", sec); + } + else + { + int ns = d.tv_nsec; + printf ("%04ld-%02d-%02d %02d:%02d:%02d.%09d\n", + tm->tm_year + 1900L, tm->tm_mon + 1, tm->tm_mday, + tm->tm_hour, tm->tm_min, tm->tm_sec, ns); + } + printf ("\t> "); + fflush (stdout); + } + return 0; +} +#endif /* TEST */ |