tclgetdate.y

tcl是工具命令语言

	    if ($1 < 100) {
		yyHour = $1;
		yyMinutes = 0;
	    } else {
		yyHour = $1 / 100;
		yyMinutes = $1 % 100;
	    }
	    yySeconds = 0;
	    yyMeridian = MER24;
	}
    }
;

o_merid : /* NULL */ {
            $$ = MER24;
        }
        | tMERIDIAN {
            $$ = $1;
        }
        ;

%%

/*
 * Month and day table.
 */
static TABLE    MonthDayTable[] = {
    { "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 }
};

/*
 * Time units table.
 */
static TABLE    UnitsTable[] = {
    { "year",           tMONTH_UNIT,    12 },
    { "month",          tMONTH_UNIT,     1 },
    { "fortnight",      tDAY_UNIT,      14 },
    { "week",           tDAY_UNIT,       7 },
    { "day",            tDAY_UNIT,       1 },
    { "hour",           tSEC_UNIT, 60 * 60 },
    { "minute",         tSEC_UNIT,      60 },
    { "min",            tSEC_UNIT,      60 },
    { "second",         tSEC_UNIT,       1 },
    { "sec",            tSEC_UNIT,       1 },
    { NULL }
};

/*
 * Assorted relative-time words.
 */
static TABLE    OtherTable[] = {
    { "tomorrow",       tDAY_UNIT,      1 },
    { "yesterday",      tDAY_UNIT,     -1 },
    { "today",          tDAY_UNIT,      0 },
    { "now",            tSEC_UNIT,      0 },
    { "last",           tUNUMBER,      -1 },
    { "this",           tSEC_UNIT,      0 },
    { "next",           tNEXT,          1 },
#if 0
    { "first",          tUNUMBER,       1 },
    { "second",         tUNUMBER,       2 },
    { "third",          tUNUMBER,       3 },
    { "fourth",         tUNUMBER,       4 },
    { "fifth",          tUNUMBER,       5 },
    { "sixth",          tUNUMBER,       6 },
    { "seventh",        tUNUMBER,       7 },
    { "eighth",         tUNUMBER,       8 },
    { "ninth",          tUNUMBER,       9 },
    { "tenth",          tUNUMBER,       10 },
    { "eleventh",       tUNUMBER,       11 },
    { "twelfth",        tUNUMBER,       12 },
#endif
    { "ago",            tAGO,   1 },
    { "epoch",          tEPOCH,   0 },
    { "stardate",       tSTARDATE, 0},
    { NULL }
};

/*
 * The timezone table.  (Note: This table was modified to not use any floating
 * point constants to work around an SGI compiler bug).
 */
static TABLE    TimezoneTable[] = {
    { "gmt",    tZONE,     HOUR( 0) },      /* Greenwich Mean */
    { "ut",     tZONE,     HOUR( 0) },      /* Universal (Coordinated) */
    { "utc",    tZONE,     HOUR( 0) },
    { "uct",    tZONE,     HOUR( 0) },      /* Universal Coordinated Time */
    { "wet",    tZONE,     HOUR( 0) },      /* Western European */
    { "bst",    tDAYZONE,  HOUR( 0) },      /* British Summer */
    { "wat",    tZONE,     HOUR( 1) },      /* West Africa */
    { "at",     tZONE,     HOUR( 2) },      /* Azores */
#if     0
    /* For completeness.  BST is also British Summer, and GST is
     * also Guam Standard. */
    { "bst",    tZONE,     HOUR( 3) },      /* Brazil Standard */
    { "gst",    tZONE,     HOUR( 3) },      /* Greenland Standard */
#endif
    { "nft",    tZONE,     HOUR( 7/2) },    /* Newfoundland */
    { "nst",    tZONE,     HOUR( 7/2) },    /* Newfoundland Standard */
    { "ndt",    tDAYZONE,  HOUR( 7/2) },    /* Newfoundland Daylight */
    { "ast",    tZONE,     HOUR( 4) },      /* Atlantic Standard */
    { "adt",    tDAYZONE,  HOUR( 4) },      /* Atlantic Daylight */
    { "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 */
    { "yst",    tZONE,     HOUR( 9) },      /* Yukon Standard */
    { "ydt",    tDAYZONE,  HOUR( 9) },      /* Yukon Daylight */
    { "hst",    tZONE,     HOUR(10) },      /* Hawaii Standard */
    { "hdt",    tDAYZONE,  HOUR(10) },      /* Hawaii Daylight */
    { "cat",    tZONE,     HOUR(10) },      /* Central Alaska */
    { "ahst",   tZONE,     HOUR(10) },      /* Alaska-Hawaii Standard */
    { "nt",     tZONE,     HOUR(11) },      /* Nome */
    { "idlw",   tZONE,     HOUR(12) },      /* International Date Line West */
    { "cet",    tZONE,    -HOUR( 1) },      /* Central European */
    { "cest",   tDAYZONE, -HOUR( 1) },      /* Central European Summer */
    { "met",    tZONE,    -HOUR( 1) },      /* Middle European */
    { "mewt",   tZONE,    -HOUR( 1) },      /* Middle European Winter */
    { "mest",   tDAYZONE, -HOUR( 1) },      /* Middle European Summer */
    { "swt",    tZONE,    -HOUR( 1) },      /* Swedish Winter */
    { "sst",    tDAYZONE, -HOUR( 1) },      /* Swedish Summer */
    { "fwt",    tZONE,    -HOUR( 1) },      /* French Winter */
    { "fst",    tDAYZONE, -HOUR( 1) },      /* French Summer */
    { "eet",    tZONE,    -HOUR( 2) },      /* Eastern Europe, USSR Zone 1 */
    { "bt",     tZONE,    -HOUR( 3) },      /* Baghdad, USSR Zone 2 */
    { "it",     tZONE,    -HOUR( 7/2) },    /* Iran */
    { "zp4",    tZONE,    -HOUR( 4) },      /* USSR Zone 3 */
    { "zp5",    tZONE,    -HOUR( 5) },      /* USSR Zone 4 */
    { "ist",    tZONE,    -HOUR(11/2) },    /* Indian Standard */
    { "zp6",    tZONE,    -HOUR( 6) },      /* USSR Zone 5 */
#if     0
    /* For completeness.  NST is also Newfoundland Stanard, nad SST is
     * also Swedish Summer. */
    { "nst",    tZONE,    -HOUR(13/2) },    /* North Sumatra */
    { "sst",    tZONE,    -HOUR( 7) },      /* South Sumatra, USSR Zone 6 */
#endif  /* 0 */
    { "wast",   tZONE,    -HOUR( 7) },      /* West Australian Standard */
    { "wadt",   tDAYZONE, -HOUR( 7) },      /* West Australian Daylight */
    { "jt",     tZONE,    -HOUR(15/2) },    /* Java (3pm in Cronusland!) */
    { "cct",    tZONE,    -HOUR( 8) },      /* China Coast, USSR Zone 7 */
    { "jst",    tZONE,    -HOUR( 9) },      /* Japan Standard, USSR Zone 8 */
    { "cast",   tZONE,    -HOUR(19/2) },    /* Central Australian Standard */
    { "cadt",   tDAYZONE, -HOUR(19/2) },    /* Central Australian Daylight */
    { "east",   tZONE,    -HOUR(10) },      /* Eastern Australian Standard */
    { "eadt",   tDAYZONE, -HOUR(10) },      /* Eastern Australian Daylight */
    { "gst",    tZONE,    -HOUR(10) },      /* Guam Standard, USSR Zone 9 */
    { "nzt",    tZONE,    -HOUR(12) },      /* New Zealand */
    { "nzst",   tZONE,    -HOUR(12) },      /* New Zealand Standard */
    { "nzdt",   tDAYZONE, -HOUR(12) },      /* New Zealand Daylight */
    { "idle",   tZONE,    -HOUR(12) },      /* International Date Line East */
    /* ADDED BY Marco Nijdam */
    { "dst",    tDST,     HOUR( 0) },       /* DST on (hour is ignored) */
    /* End ADDED */
    {  NULL  }
};

/*
 * Military timezone table.
 */
static TABLE    MilitaryTable[] = {
    { "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 }
};


/*
 * Dump error messages in the bit bucket.
 */
static void
yyerror(s)
    char  *s;
{
}


static time_t
ToSeconds(Hours, Minutes, Seconds, Meridian)
    time_t      Hours;
    time_t      Minutes;
    time_t      Seconds;
    MERIDIAN    Meridian;
{
    if (Minutes < 0 || Minutes > 59 || Seconds < 0 || Seconds > 59)
        return -1;
    switch (Meridian) {
    case MER24:
        if (Hours < 0 || Hours > 23)
            return -1;
        return (Hours * 60L + Minutes) * 60L + Seconds;
    case MERam:
        if (Hours < 1 || Hours > 12)
            return -1;
        return ((Hours % 12) * 60L + Minutes) * 60L + Seconds;
    case MERpm:
        if (Hours < 1 || Hours > 12)
            return -1;
        return (((Hours % 12) + 12) * 60L + Minutes) * 60L + Seconds;
    }
    return -1;  /* Should never be reached */
}

/*
 *-----------------------------------------------------------------------------
 *
 * Convert --
 *
 *      Convert a {month, day, year, hours, minutes, seconds, meridian, dst}
 *      tuple into a clock seconds value.
 *
 * Results:
 *      0 or -1 indicating success or failure.
 *
 * Side effects:
 *      Fills TimePtr with the computed value.
 *
 *-----------------------------------------------------------------------------
 */
static int
Convert(Month, Day, Year, Hours, Minutes, Seconds, Meridian, DSTmode, TimePtr)
    time_t      Month;
    time_t      Day;
    time_t      Year;
    time_t      Hours;
    time_t      Minutes;
    time_t      Seconds;
    MERIDIAN    Meridian;
    DSTMODE     DSTmode;
    time_t     *TimePtr;
{
    static int  DaysInMonth[12] = {
        31, 0, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
    };
    time_t tod;
    time_t Julian;
    int i;

    /* Figure out how many days are in February for the given year.
     * Every year divisible by 4 is a leap year.
     * But, every year divisible by 100 is not a leap year.
     * But, every year divisible by 400 is a leap year after all.
     */
    DaysInMonth[1] = IsLeapYear(Year) ? 29 : 28;

    /* Check the inputs for validity */
    if (Month < 1 || Month > 12
	    || Year < START_OF_TIME || Year > END_OF_TIME
	    || Day < 1 || Day > DaysInMonth[(int)--Month])
        return -1;

    /* Start computing the value.  First determine the number of days
     * represented by the date, then multiply by the number of seconds/day.
     */
    for (Julian = Day - 1, i = 0; i < Month; i++)
        Julian += DaysInMonth[i];
    if (Year >= EPOCH) {
        for (i = EPOCH; i < Year; i++)
            Julian += 365 + IsLeapYear(i);
    } else {
        for (i = Year; i < EPOCH; i++)
            Julian -= 365 + IsLeapYear(i);
    }
    Julian *= SECSPERDAY;

    /* Add the timezone offset ?? */
    Julian += yyTimezone * 60L;

    /* Add the number of seconds represented by the time component */
    if ((tod = ToSeconds(Hours, Minutes, Seconds, Meridian)) < 0)
        return -1;
    Julian += tod;

    /* Perform a preliminary DST compensation ?? */
    if (DSTmode == DSTon
     || (DSTmode == DSTmaybe && TclpGetDate((TclpTime_t)&Julian, 0)->tm_isdst))
        Julian -= 60 * 60;
    *TimePtr = Julian;
    return 0;
}


static time_t
DSTcorrect(Start, Future)
    time_t      Start;
    time_t      Future;
{
    time_t      StartDay;
    time_t      FutureDay;
    StartDay = (TclpGetDate((TclpTime_t)&Start, 0)->tm_hour + 1) % 24;
    FutureDay = (TclpGetDate((TclpTime_t)&Future, 0)->tm_hour + 1) % 24;
    return (Future - Start) + (StartDay - FutureDay) * 60L * 60L;
}


static time_t
NamedDay(Start, DayOrdinal, DayNumber)
    time_t      Start;
    time_t      DayOrdinal;
    time_t      DayNumber;
{
    struct tm   *tm;
    time_t      now;

    now = Start;
    tm = TclpGetDate((TclpTime_t)&now, 0);
    now += SECSPERDAY * ((DayNumber - tm->tm_wday + 7) % 7);
    now += 7 * SECSPERDAY * (DayOrdinal <= 0 ? DayOrdinal : DayOrdinal - 1);
    return DSTcorrect(Start, now);
}

static time_t
NamedMonth(Start, MonthOrdinal, MonthNumber)
    time_t Start;
    time_t MonthOrdinal;
    time_t MonthNumber;
{
    struct tm *tm;
    time_t now;
    int result;
    
    now = Start;
    tm = TclpGetDate((TclpTime_t)&now, 0);
    /* To compute the next n'th month, we use this alg:
     * add n to year value
     * if currentMonth < requestedMonth decrement year value by 1 (so that
     *  doing next february from january gives us february of the current year)
     * set day to 1, time to 0
     */
    tm->tm_year += MonthOrdinal;
    if (tm->tm_mon < MonthNumber - 1) {
	tm->tm_year--;
    }
    result = Convert(MonthNumber, (time_t) 1, tm->tm_year + TM_YEAR_BASE,
	    (time_t) 0, (time_t) 0, (time_t) 0, MER24, DSTmaybe, &now);
    if (result < 0) {