Initial revision

1 files changed, 958 insertions, 0 deletions

diff --git a/generic/tclGetDate.y b/generic/tclGetDate.y
new file mode 100644
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--- /dev/null
+++ b/generic/tclGetDate.y
@@ -0,0 +1,958 @@
+/* 
+ * tclGetDate.y --
+ *
+ *	Contains yacc grammar for parsing date and time strings.
+ *	The output of this file should be the file tclDate.c which
+ *	is used directly in the Tcl sources.
+ *
+ * Copyright (c) 1992-1995 Karl Lehenbauer and Mark Diekhans.
+ * Copyright (c) 1995-1997 Sun Microsystems, Inc.
+ *
+ * See the file "license.terms" for information on usage and redistribution
+ * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ *
+ * SCCS: @(#) tclGetDate.y 1.34 97/02/03 14:53:54
+ */
+
+%{
+/* 
+ * tclDate.c --
+ *
+ *	This file is generated from a yacc grammar defined in
+ *	the file tclGetDate.y.  It should not be edited directly.
+ *
+ * Copyright (c) 1992-1995 Karl Lehenbauer and Mark Diekhans.
+ * Copyright (c) 1995-1997 Sun Microsystems, Inc.
+ *
+ * See the file "license.terms" for information on usage and redistribution
+ * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ *
+ * SCCSID
+ */
+
+#include "tclInt.h"
+#include "tclPort.h"
+
+#ifdef MAC_TCL
+#   define EPOCH           1904
+#   define START_OF_TIME   1904
+#   define END_OF_TIME     2039
+#else
+#   define EPOCH           1970
+#   define START_OF_TIME   1902
+#   define END_OF_TIME     2037
+#endif
+
+/*
+ * The offset of tm_year of struct tm returned by localtime, gmtime, etc.
+ * I don't know how universal this is; K&R II, the NetBSD manpages, and
+ * ../compat/strftime.c all agree that tm_year is the year-1900.  However,
+ * some systems may have a different value.  This #define should be the
+ * same as in ../compat/strftime.c.
+ */
+#define TM_YEAR_BASE 1900
+
+#define HOUR(x)         ((int) (60 * x))
+#define SECSPERDAY      (24L * 60L * 60L)
+
+
+/*
+ *  An entry in the lexical lookup table.
+ */
+typedef struct _TABLE {
+    char        *name;
+    int         type;
+    time_t      value;
+} TABLE;
+
+
+/*
+ *  Daylight-savings mode:  on, off, or not yet known.
+ */
+typedef enum _DSTMODE {
+    DSTon, DSToff, DSTmaybe
+} DSTMODE;
+
+/*
+ *  Meridian:  am, pm, or 24-hour style.
+ */
+typedef enum _MERIDIAN {
+    MERam, MERpm, MER24
+} MERIDIAN;
+
+
+/*
+ *  Global variables.  We could get rid of most of these by using a good
+ *  union as the yacc stack.  (This routine was originally written before
+ *  yacc had the %union construct.)  Maybe someday; right now we only use
+ *  the %union very rarely.
+ */
+static char     *yyInput;
+static DSTMODE  yyDSTmode;
+static time_t   yyDayOrdinal;
+static time_t   yyDayNumber;
+static int      yyHaveDate;
+static int      yyHaveDay;
+static int      yyHaveRel;
+static int      yyHaveTime;
+static int      yyHaveZone;
+static time_t   yyTimezone;
+static time_t   yyDay;
+static time_t   yyHour;
+static time_t   yyMinutes;
+static time_t   yyMonth;
+static time_t   yySeconds;
+static time_t   yyYear;
+static MERIDIAN yyMeridian;
+static time_t   yyRelMonth;
+static time_t   yyRelSeconds;
+
+
+/*
+ * Prototypes of internal functions.
+ */
+static void	yyerror _ANSI_ARGS_((char *s));
+static time_t	ToSeconds _ANSI_ARGS_((time_t Hours, time_t Minutes,
+		    time_t Seconds, MERIDIAN Meridian));
+static int	Convert _ANSI_ARGS_((time_t Month, time_t Day, time_t Year,
+		    time_t Hours, time_t Minutes, time_t Seconds,
+		    MERIDIAN Meridia, DSTMODE DSTmode, time_t *TimePtr));
+static time_t	DSTcorrect _ANSI_ARGS_((time_t Start, time_t Future));
+static time_t	RelativeDate _ANSI_ARGS_((time_t Start, time_t DayOrdinal,
+		    time_t DayNumber));
+static int	RelativeMonth _ANSI_ARGS_((time_t Start, time_t RelMonth,
+		    time_t *TimePtr));
+static int	LookupWord _ANSI_ARGS_((char *buff));
+static int	yylex _ANSI_ARGS_((void));
+
+int
+yyparse _ANSI_ARGS_((void));
+%}
+
+%union {
+    time_t              Number;
+    enum _MERIDIAN      Meridian;
+}
+
+%token  tAGO tDAY tDAYZONE tID tMERIDIAN tMINUTE_UNIT tMONTH tMONTH_UNIT
+%token  tSEC_UNIT tSNUMBER tUNUMBER tZONE tEPOCH tDST
+
+%type   <Number>        tDAY tDAYZONE tMINUTE_UNIT tMONTH tMONTH_UNIT tDST
+%type   <Number>        tSEC_UNIT tSNUMBER tUNUMBER tZONE
+%type   <Meridian>      tMERIDIAN o_merid
+
+%%
+
+spec    : /* NULL */
+        | spec item
+        ;
+
+item    : time {
+            yyHaveTime++;
+        }
+        | zone {
+            yyHaveZone++;
+        }
+        | date {
+            yyHaveDate++;
+        }
+        | day {
+            yyHaveDay++;
+        }
+        | rel {
+            yyHaveRel++;
+        }
+        | number
+        ;
+
+time    : tUNUMBER tMERIDIAN {
+            yyHour = $1;
+            yyMinutes = 0;
+            yySeconds = 0;
+            yyMeridian = $2;
+        }
+        | tUNUMBER ':' tUNUMBER o_merid {
+            yyHour = $1;
+            yyMinutes = $3;
+            yySeconds = 0;
+            yyMeridian = $4;
+        }
+        | tUNUMBER ':' tUNUMBER tSNUMBER {
+            yyHour = $1;
+            yyMinutes = $3;
+            yyMeridian = MER24;
+            yyDSTmode = DSToff;
+            yyTimezone = - ($4 % 100 + ($4 / 100) * 60);
+        }
+        | tUNUMBER ':' tUNUMBER ':' tUNUMBER o_merid {
+            yyHour = $1;
+            yyMinutes = $3;
+            yySeconds = $5;
+            yyMeridian = $6;
+        }
+        | tUNUMBER ':' tUNUMBER ':' tUNUMBER tSNUMBER {
+            yyHour = $1;
+            yyMinutes = $3;
+            yySeconds = $5;
+            yyMeridian = MER24;
+            yyDSTmode = DSToff;
+            yyTimezone = - ($6 % 100 + ($6 / 100) * 60);
+        }
+        ;
+
+zone    : tZONE tDST {
+            yyTimezone = $1;
+            yyDSTmode = DSTon;
+        }
+        | tZONE {
+            yyTimezone = $1;
+            yyDSTmode = DSToff;
+        }
+        | tDAYZONE {
+            yyTimezone = $1;
+            yyDSTmode = DSTon;
+        }
+        ;
+
+day     : tDAY {
+            yyDayOrdinal = 1;
+            yyDayNumber = $1;
+        }
+        | tDAY ',' {
+            yyDayOrdinal = 1;
+            yyDayNumber = $1;
+        }
+        | tUNUMBER tDAY {
+            yyDayOrdinal = $1;
+            yyDayNumber = $2;
+        }
+        ;
+
+date    : tUNUMBER '/' tUNUMBER {
+            yyMonth = $1;
+            yyDay = $3;
+        }
+        | tUNUMBER '/' tUNUMBER '/' tUNUMBER {
+            yyMonth = $1;
+            yyDay = $3;
+            yyYear = $5;
+        }
+        | tMONTH tUNUMBER {
+            yyMonth = $1;
+            yyDay = $2;
+        }
+        | tMONTH tUNUMBER ',' tUNUMBER {
+            yyMonth = $1;
+            yyDay = $2;
+            yyYear = $4;
+        }
+        | tUNUMBER tMONTH {
+            yyMonth = $2;
+            yyDay = $1;
+        }
+		  | tEPOCH {
+				yyMonth = 1;
+				yyDay = 1;
+				yyYear = EPOCH;
+		  }
+        | tUNUMBER tMONTH tUNUMBER {
+            yyMonth = $2;
+            yyDay = $1;
+            yyYear = $3;
+        }
+        ;
+
+rel     : relunit tAGO {
+            yyRelSeconds = -yyRelSeconds;
+            yyRelMonth = -yyRelMonth;
+        }
+        | relunit
+        ;
+
+relunit : tUNUMBER tMINUTE_UNIT {
+            yyRelSeconds += $1 * $2 * 60L;
+        }
+        | tSNUMBER tMINUTE_UNIT {
+            yyRelSeconds += $1 * $2 * 60L;
+        }
+        | tMINUTE_UNIT {
+            yyRelSeconds += $1 * 60L;
+        }
+        | tSNUMBER tSEC_UNIT {
+            yyRelSeconds += $1;
+        }
+        | tUNUMBER tSEC_UNIT {
+            yyRelSeconds += $1;
+        }
+        | tSEC_UNIT {
+            yyRelSeconds++;
+        }
+        | tSNUMBER tMONTH_UNIT {
+            yyRelMonth += $1 * $2;
+        }
+        | tUNUMBER tMONTH_UNIT {
+            yyRelMonth += $1 * $2;
+        }
+        | tMONTH_UNIT {
+            yyRelMonth += $1;
+        }
+        ;
+
+number  : tUNUMBER
+    {
+	if (yyHaveTime && yyHaveDate && !yyHaveRel) {
+	    yyYear = $1;
+	} else {
+	    yyHaveTime++;
+	    if ($1 < 100) {
+		yyHour = 0;
+		yyMinutes = $1;
+	    } 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",      tMINUTE_UNIT,   14 * 24 * 60 },
+    { "week",           tMINUTE_UNIT,   7 * 24 * 60 },
+    { "day",            tMINUTE_UNIT,   1 * 24 * 60 },
+    { "hour",           tMINUTE_UNIT,   60 },
+    { "minute",         tMINUTE_UNIT,   1 },
+    { "min",            tMINUTE_UNIT,   1 },
+    { "second",         tSEC_UNIT,      1 },
+    { "sec",            tSEC_UNIT,      1 },
+    { NULL }
+};
+
+/*
+ * Assorted relative-time words.
+ */
+static TABLE    OtherTable[] = {
+    { "tomorrow",       tMINUTE_UNIT,   1 * 24 * 60 },
+    { "yesterday",      tMINUTE_UNIT,   -1 * 24 * 60 },
+    { "today",          tMINUTE_UNIT,   0 },
+    { "now",            tMINUTE_UNIT,   0 },
+    { "last",           tUNUMBER,       -1 },
+    { "this",           tMINUTE_UNIT,   0 },
+    { "next",           tUNUMBER,       2 },
+#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 },
+    { 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) },
+    { "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 */
+    { "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 */
+}
+
+
+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;
+
+    DaysInMonth[1] = Year % 4 == 0 && (Year % 100 != 0 || Year % 400 == 0)
+                    ? 29 : 28;
+    if (Month < 1 || Month > 12
+     || Year < START_OF_TIME || Year > END_OF_TIME
+     || Day < 1 || Day > DaysInMonth[(int)--Month])
+        return -1;
+
+    for (Julian = Day - 1, i = 0; i < Month; i++)
+        Julian += DaysInMonth[i];
+    if (Year >= EPOCH) {
+        for (i = EPOCH; i < Year; i++)
+            Julian += 365 + (i % 4 == 0);
+    } else {
+        for (i = Year; i < EPOCH; i++)
+            Julian -= 365 + (i % 4 == 0);
+    }
+    Julian *= SECSPERDAY;
+    Julian += yyTimezone * 60L;
+    if ((tod = ToSeconds(Hours, Minutes, Seconds, Meridian)) < 0)
+        return -1;
+    Julian += tod;
+    if (DSTmode == DSTon
+     || (DSTmode == DSTmaybe && TclpGetDate(&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(&Start, 0)->tm_hour + 1) % 24;
+    FutureDay = (TclpGetDate(&Future, 0)->tm_hour + 1) % 24;
+    return (Future - Start) + (StartDay - FutureDay) * 60L * 60L;
+}
+
+
+static time_t
+RelativeDate(Start, DayOrdinal, DayNumber)
+    time_t      Start;
+    time_t      DayOrdinal;
+    time_t      DayNumber;
+{
+    struct tm   *tm;
+    time_t      now;
+
+    now = Start;
+    tm = TclpGetDate(&now, 0);
+    now += SECSPERDAY * ((DayNumber - tm->tm_wday + 7) % 7);
+    now += 7 * SECSPERDAY * (DayOrdinal <= 0 ? DayOrdinal : DayOrdinal - 1);
+    return DSTcorrect(Start, now);
+}
+
+
+static int
+RelativeMonth(Start, RelMonth, TimePtr)
+    time_t Start;
+    time_t RelMonth;
+    time_t *TimePtr;
+{
+    struct tm *tm;
+    time_t Month;
+    time_t Year;
+    time_t Julian;
+    int result;
+
+    if (RelMonth == 0) {
+        *TimePtr = 0;
+        return 0;
+    }
+    tm = TclpGetDate(&Start, 0);
+    Month = 12 * (tm->tm_year + TM_YEAR_BASE) + tm->tm_mon + RelMonth;
+    Year = Month / 12;
+    Month = Month % 12 + 1;
+    result = Convert(Month, (time_t) tm->tm_mday, Year,
+	    (time_t) tm->tm_hour, (time_t) tm->tm_min, (time_t) tm->tm_sec,
+	    MER24, DSTmaybe, &Julian);
+    /*
+     * The following iteration takes into account the case were we jump
+     * into a "short month".  Far example, "one month from Jan 31" will
+     * fail because there is no Feb 31.  The code below will reduce the
+     * day and try converting the date until we succed or the date equals
+     * 28 (which always works unless the date is bad in another way).
+     */
+
+    while ((result != 0) && (tm->tm_mday > 28)) {
+	tm->tm_mday--;
+	result = Convert(Month, (time_t) tm->tm_mday, Year,
+		(time_t) tm->tm_hour, (time_t) tm->tm_min, (time_t) tm->tm_sec,
+		MER24, DSTmaybe, &Julian);
+    }
+    if (result != 0) {
+	return -1;
+    }
+    *TimePtr = DSTcorrect(Start, Julian);
+    return 0;
+}
+
+
+static int
+LookupWord(buff)
+    char                *buff;
+{
+    register char *p;
+    register char *q;
+    register TABLE *tp;
+    int i;
+    int abbrev;
+
+    /*
+     * Make it lowercase.
+     */
+    for (p = buff; *p; p++) {
+        if (isupper(UCHAR(*p))) {
+            *p = (char) tolower(UCHAR(*p));
+	}
+    }
+
+    if (strcmp(buff, "am") == 0 || strcmp(buff, "a.m.") == 0) {
+        yylval.Meridian = MERam;
+        return tMERIDIAN;
+    }
+    if (strcmp(buff, "pm") == 0 || strcmp(buff, "p.m.") == 0) {
+        yylval.Meridian = MERpm;
+        return tMERIDIAN;
+    }
+
+    /*
+     * See if we have an abbreviation for a month.
+     */
+    if (strlen(buff) == 3) {
+        abbrev = 1;
+    } else if (strlen(buff) == 4 && buff[3] == '.') {
+        abbrev = 1;
+        buff[3] = '\0';
+    } else {
+        abbrev = 0;
+    }
+
+    for (tp = MonthDayTable; tp->name; tp++) {
+        if (abbrev) {
+            if (strncmp(buff, tp->name, 3) == 0) {
+                yylval.Number = tp->value;
+                return tp->type;
+            }
+        } else if (strcmp(buff, tp->name) == 0) {
+            yylval.Number = tp->value;
+            return tp->type;
+        }
+    }
+
+    for (tp = TimezoneTable; tp->name; tp++) {
+        if (strcmp(buff, tp->name) == 0) {
+            yylval.Number = tp->value;
+            return tp->type;
+        }
+    }
+
+    for (tp = UnitsTable; tp->name; tp++) {
+        if (strcmp(buff, tp->name) == 0) {
+            yylval.Number = tp->value;
+            return tp->type;
+        }
+    }
+
+    /*
+     * Strip off any plural and try the units table again.
+     */
+    i = strlen(buff) - 1;
+    if (buff[i] == 's') {
+        buff[i] = '\0';
+        for (tp = UnitsTable; tp->name; tp++) {
+            if (strcmp(buff, tp->name) == 0) {
+                yylval.Number = tp->value;
+                return tp->type;
+            }
+	}
+    }
+
+    for (tp = OtherTable; tp->name; tp++) {
+        if (strcmp(buff, tp->name) == 0) {
+            yylval.Number = tp->value;
+            return tp->type;
+        }
+    }
+
+    /*
+     * Military timezones.
+     */
+    if (buff[1] == '\0' && isalpha(UCHAR(*buff))) {
+        for (tp = MilitaryTable; tp->name; tp++) {
+            if (strcmp(buff, tp->name) == 0) {
+                yylval.Number = tp->value;
+                return tp->type;
+            }
+	}
+    }
+
+    /*
+     * Drop out any periods and try the timezone table again.
+     */
+    for (i = 0, p = q = buff; *q; q++)
+        if (*q != '.') {
+            *p++ = *q;
+        } else {
+            i++;
+	}
+    *p = '\0';
+    if (i) {
+        for (tp = TimezoneTable; tp->name; tp++) {
+            if (strcmp(buff, tp->name) == 0) {
+                yylval.Number = tp->value;
+                return tp->type;
+            }
+	}
+    }
+    
+    return tID;
+}
+
+
+static int
+yylex()
+{
+    register char       c;
+    register char       *p;
+    char                buff[20];
+    int                 Count;
+    int                 sign;
+
+    for ( ; ; ) {
+        while (isspace((unsigned char) (*yyInput))) {
+            yyInput++;
+	}
+
+        if (isdigit(c = *yyInput) || c == '-' || c == '+') {
+            if (c == '-' || c == '+') {
+                sign = c == '-' ? -1 : 1;
+                if (!isdigit(*++yyInput)) {
+                    /*
+		     * skip the '-' sign
+		     */
+                    continue;
+		}
+            } else {
+                sign = 0;
+	    }
+            for (yylval.Number = 0; isdigit(c = *yyInput++); ) {
+                yylval.Number = 10 * yylval.Number + c - '0';
+	    }
+            yyInput--;
+            if (sign < 0) {
+                yylval.Number = -yylval.Number;
+	    }
+            return sign ? tSNUMBER : tUNUMBER;
+        }
+        if (isalpha(UCHAR(c))) {
+            for (p = buff; isalpha(c = *yyInput++) || c == '.'; ) {
+                if (p < &buff[sizeof buff - 1]) {
+                    *p++ = c;
+		}
+	    }
+            *p = '\0';
+            yyInput--;
+            return LookupWord(buff);
+        }
+        if (c != '(') {
+            return *yyInput++;
+	}
+        Count = 0;
+        do {
+            c = *yyInput++;
+            if (c == '\0') {
+                return c;
+	    } else if (c == '(') {
+                Count++;
+	    } else if (c == ')') {
+                Count--;
+	    }
+        } while (Count > 0);
+    }
+}
+
+/*
+ * Specify zone is of -50000 to force GMT.  (This allows BST to work).
+ */
+
+int
+TclGetDate(p, now, zone, timePtr)
+    char *p;
+    unsigned long now;
+    long zone;
+    unsigned long *timePtr;
+{
+    struct tm *tm;
+    time_t Start;
+    time_t Time;
+    time_t tod;
+    int thisyear;
+
+    yyInput = p;
+    tm = TclpGetDate((time_t *) &now, 0);
+    thisyear = tm->tm_year + TM_YEAR_BASE;
+    yyYear = thisyear;
+    yyMonth = tm->tm_mon + 1;
+    yyDay = tm->tm_mday;
+    yyTimezone = zone;
+    if (zone == -50000) {
+        yyDSTmode = DSToff;  /* assume GMT */
+        yyTimezone = 0;
+    } else {
+        yyDSTmode = DSTmaybe;
+    }
+    yyHour = 0;
+    yyMinutes = 0;
+    yySeconds = 0;
+    yyMeridian = MER24;
+    yyRelSeconds = 0;
+    yyRelMonth = 0;
+    yyHaveDate = 0;
+    yyHaveDay = 0;
+    yyHaveRel = 0;
+    yyHaveTime = 0;
+    yyHaveZone = 0;
+
+    if (yyparse() || yyHaveTime > 1 || yyHaveZone > 1 || yyHaveDate > 1 ||
+	    yyHaveDay > 1) {
+        return -1;
+    }
+    
+    if (yyHaveDate || yyHaveTime || yyHaveDay) {
+	if (TclDateYear < 0) {
+	    TclDateYear = -TclDateYear;
+	}
+	/*
+	 * The following line handles years that are specified using
+	 * only two digits.  The line of code below implements a policy
+	 * defined by the X/Open workgroup on the millinium rollover.
+	 * Note: some of those dates may not actually be valid on some
+	 * platforms.  The POSIX standard startes that the dates 70-99
+	 * shall refer to 1970-1999 and 00-38 shall refer to 2000-2038.
+	 * This later definition should work on all platforms.
+	 */
+
+	if (TclDateYear < 100) {
+	    if (TclDateYear >= 69) {
+		TclDateYear += 1900;
+	    } else {
+		TclDateYear += 2000;
+	    }
+	}
+	if (Convert(yyMonth, yyDay, yyYear, yyHour, yyMinutes, yySeconds,
+		yyMeridian, yyDSTmode, &Start) < 0) {
+            return -1;
+	}
+    } else {
+        Start = now;
+        if (!yyHaveRel) {
+            Start -= ((tm->tm_hour * 60L) + tm->tm_min * 60L) + tm->tm_sec;
+	}
+    }
+
+    Start += yyRelSeconds;
+    if (RelativeMonth(Start, yyRelMonth, &Time) < 0) {
+        return -1;
+    }
+    Start += Time;
+
+    if (yyHaveDay && !yyHaveDate) {
+        tod = RelativeDate(Start, yyDayOrdinal, yyDayNumber);
+        Start += tod;
+    }
+
+    *timePtr = Start;
+    return 0;
+}