path: root/generic/tclDate.h

/*
 * tclDate.h --
 *
 *	This header file handles common usage of clock primitives
 *	between tclDate.c (yacc), tclClock.c and tclClockFmt.c.
 *
 * Copyright (c) 2014 Serg G. Brester (aka sebres)
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 */

#ifndef _TCLCLOCK_H
#define _TCLCLOCK_H

/*
 * Constants
 */

#define JULIAN_DAY_POSIX_EPOCH		2440588
#define GREGORIAN_CHANGE_DATE		2361222
#define SECONDS_PER_DAY			86400
#define JULIAN_SEC_POSIX_EPOCH	      (((Tcl_WideInt) JULIAN_DAY_POSIX_EPOCH) \
					* SECONDS_PER_DAY)
#define FOUR_CENTURIES			146097	/* days */
#define JDAY_1_JAN_1_CE_JULIAN		1721424
#define JDAY_1_JAN_1_CE_GREGORIAN	1721426
#define ONE_CENTURY_GREGORIAN		36524	/* days */
#define FOUR_YEARS			1461	/* days */
#define ONE_YEAR			365	/* days */

#define RODDENBERRY			1946	/* Another epoch (Hi, Jeff!) */


#define CLF_OPTIONAL	       (1 << 0) /* token is non mandatory */
#define CLF_POSIXSEC	       (1 << 1)
#define CLF_LOCALSEC	       (1 << 2)
#define CLF_JULIANDAY	       (1 << 3)
#define CLF_TIME	       (1 << 4)
#define CLF_ZONE	       (1 << 5)
#define CLF_CENTURY	       (1 << 6)
#define CLF_DAYOFMONTH	       (1 << 7)
#define CLF_DAYOFYEAR	       (1 << 8)
#define CLF_MONTH	       (1 << 9)
#define CLF_YEAR	       (1 << 10)
#define CLF_DAYOFWEEK	       (1 << 11)
#define CLF_ISO8601YEAR	       (1 << 12)
#define CLF_ISO8601WEAK	       (1 << 13)
#define CLF_ISO8601CENTURY     (1 << 14)

#define CLF_SIGNED	       (1 << 15)

/* extra flags used outside of scan/format-tokens too (int, not a short int) */
#define CLF_RELCONV	       (1 << 17)
#define CLF_ORDINALMONTH       (1 << 18)

/* On demand (lazy) assemble flags */
#define CLF_ASSEMBLE_DATE      (1 << 28) /* assemble year, month, etc. using julianDay */
#define CLF_ASSEMBLE_JULIANDAY (1 << 29) /* assemble julianDay using year, month, etc. */
#define CLF_ASSEMBLE_SECONDS   (1 << 30) /* assemble localSeconds (and seconds at end) */

#define CLF_HAVEDATE	       (CLF_DAYOFMONTH|CLF_MONTH|CLF_YEAR)
#define CLF_DATE	       (CLF_JULIANDAY | CLF_DAYOFMONTH | CLF_DAYOFYEAR | \
				CLF_MONTH | CLF_YEAR | CLF_ISO8601YEAR | \
				CLF_DAYOFWEEK | CLF_ISO8601WEAK)

#define TCL_MIN_SECONDS			-0x00F0000000000000L
#define TCL_MAX_SECONDS			 0x00F0000000000000L
#define TCL_INV_SECONDS			(TCL_MIN_SECONDS-1)

/*
 * Enumeration of the string literals used in [clock]
 */

typedef enum ClockLiteral {
    LIT__NIL,
    LIT__DEFAULT_FORMAT,
    LIT_SYSTEM,		LIT_CURRENT,		LIT_C,
    LIT_BCE,		LIT_CE,
    LIT_DAYOFMONTH,	LIT_DAYOFWEEK,		LIT_DAYOFYEAR,
    LIT_ERA,		LIT_GMT,		LIT_GREGORIAN,
    LIT_INTEGER_VALUE_TOO_LARGE,
    LIT_ISO8601WEEK,	LIT_ISO8601YEAR,
    LIT_JULIANDAY,	LIT_LOCALSECONDS,
    LIT_MONTH,
    LIT_SECONDS,	LIT_TZNAME,		LIT_TZOFFSET,
    LIT_YEAR,
    LIT_TZDATA,
    LIT_GETSYSTEMTIMEZONE,
    LIT_SETUPTIMEZONE,
    LIT_MCGET,
    LIT_GETSYSTEMLOCALE, LIT_GETCURRENTLOCALE,
    LIT_LOCALIZE_FORMAT,
    LIT__END
} ClockLiteral;

#define CLOCK_LITERAL_ARRAY(litarr) static const char *const litarr[] = { \
    "", \
    "%a %b %d %H:%M:%S %Z %Y", \
    "system",		"current",		"C", \
    "BCE",		"CE", \
    "dayOfMonth",	"dayOfWeek",		"dayOfYear", \
    "era",		":GMT",			"gregorian", \
    "integer value too large to represent", \
    "iso8601Week",	"iso8601Year", \
    "julianDay",	"localSeconds", \
    "month", \
    "seconds",		"tzName",		"tzOffset", \
    "year", \
    "::tcl::clock::TZData", \
    "::tcl::clock::GetSystemTimeZone", \
    "::tcl::clock::SetupTimeZone", \
    "::tcl::clock::mcget", \
    "::tcl::clock::GetSystemLocale", "::tcl::clock::mclocale", \
    "::tcl::clock::LocalizeFormat" \
}

/*
 * Enumeration of the msgcat literals used in [clock]
 */

typedef enum ClockMsgCtLiteral {
    MCLIT__NIL, /* placeholder */
    MCLIT_MONTHS_FULL,	MCLIT_MONTHS_ABBREV,  MCLIT_MONTHS_COMB,
    MCLIT_DAYS_OF_WEEK_FULL,  MCLIT_DAYS_OF_WEEK_ABBREV,  MCLIT_DAYS_OF_WEEK_COMB,
    MCLIT_AM,  MCLIT_PM,
    MCLIT_LOCALE_ERAS,
    MCLIT_BCE,	 MCLIT_CE,
    MCLIT_BCE2,	 MCLIT_CE2,
    MCLIT_BCE3,	 MCLIT_CE3,
    MCLIT_LOCALE_NUMERALS,
    MCLIT__END
} ClockMsgCtLiteral;

#define CLOCK_LOCALE_LITERAL_ARRAY(litarr, pref) static const char *const litarr[] = { \
    pref "", \
    pref "MONTHS_FULL", pref "MONTHS_ABBREV", pref "MONTHS_COMB", \
    pref "DAYS_OF_WEEK_FULL", pref "DAYS_OF_WEEK_ABBREV", pref "DAYS_OF_WEEK_COMB", \
    pref "AM", pref "PM", \
    pref "LOCALE_ERAS", \
    pref "BCE",	   pref "CE", \
    pref "b.c.e.", pref "c.e.", \
    pref "b.c.",   pref "a.d.", \
    pref "LOCALE_NUMERALS", \
}

/*
 * Structure containing the fields used in [clock format] and [clock scan]
 */

typedef struct TclDateFields {

    /* Cacheable fields:	 */

    Tcl_WideInt seconds;	/* Time expressed in seconds from the Posix
				 * epoch */
    Tcl_WideInt localSeconds;	/* Local time expressed in nominal seconds
				 * from the Posix epoch */
    int tzOffset;		/* Time zone offset in seconds east of
				 * Greenwich */
    Tcl_WideInt julianDay;	/* Julian Day Number in local time zone */
    int isBce;			/* 1 if BCE */
    int gregorian;		/* Flag == 1 if the date is Gregorian */
    int year;			/* Year of the era */
    int dayOfYear;		/* Day of the year (1 January == 1) */
    int month;			/* Month number */
    int dayOfMonth;		/* Day of the month */
    int iso8601Year;		/* ISO8601 week-based year */
    int iso8601Week;		/* ISO8601 week number */
    int dayOfWeek;		/* Day of the week */
    int hour;			/* Hours of day (in-between time only calculation) */
    int minutes;		/* Minutes of hour (in-between time only calculation) */
    int secondOfMin;		/* Seconds of minute (in-between time only calculation) */
    int secondOfDay;		/* Seconds of day (in-between time only calculation) */

    /* Non cacheable fields:	 */

    Tcl_Obj *tzName;		/* Name (or corresponding DST-abbreviation) of the
				 * time zone, if set the refCount is incremented */
} TclDateFields;

#define ClockCacheableDateFieldsSize \
    offsetof(TclDateFields, tzName)

/*
 * Meridian: am, pm, or 24-hour style.
 */

typedef enum _MERIDIAN {
    MERam, MERpm, MER24
} MERIDIAN;

/*
 * Structure contains return parsed fields.
 */

typedef struct DateInfo {
    const char *dateStart;
    const char *dateInput;
    const char *dateEnd;

    TclDateFields date;

    int		flags;		/* Signals parts of date/time get found */
    int		errFlags;	/* Signals error (part of date/time found twice) */

    MERIDIAN dateMeridian;

    int dateTimezone;
    int dateDSTmode;

    int dateRelMonth;
    int dateRelDay;
    int dateRelSeconds;

    int dateMonthOrdinalIncr;
    int dateMonthOrdinal;

    int dateDayOrdinal;

    int *dateRelPointer;

    int dateSpaceCount;
    int dateDigitCount;

    int dateCentury;

    Tcl_Obj* messages;	    /* Error messages */
    const char* separatrix; /* String separating messages */
} DateInfo;

#define yydate	    (info->date)  /* Date fields used for converting */

#define yyDay	    (info->date.dayOfMonth)
#define yyMonth	    (info->date.month)
#define yyYear	    (info->date.year)

#define yyHour	    (info->date.hour)
#define yyMinutes   (info->date.minutes)
#define yySeconds   (info->date.secondOfMin)
#define yySecondOfDay (info->date.secondOfDay)

#define yyDSTmode   (info->dateDSTmode)
#define yyDayOrdinal	(info->dateDayOrdinal)
#define yyDayOfWeek (info->date.dayOfWeek)
#define yyMonthOrdinalIncr  (info->dateMonthOrdinalIncr)
#define yyMonthOrdinal	(info->dateMonthOrdinal)
#define yyTimezone  (info->dateTimezone)
#define yyMeridian  (info->dateMeridian)
#define yyRelMonth  (info->dateRelMonth)
#define yyRelDay    (info->dateRelDay)
#define yyRelSeconds	(info->dateRelSeconds)
#define yyRelPointer	(info->dateRelPointer)
#define yyInput	    (info->dateInput)
#define yyDigitCount	(info->dateDigitCount)
#define yySpaceCount	(info->dateSpaceCount)

static inline void
ClockInitDateInfo(DateInfo *info) {
    memset(info, 0, sizeof(DateInfo));
}

/*
 * Structure containing the command arguments supplied to [clock format] and [clock scan]
 */

#define CLF_VALIDATE	(1 << 2)
#define CLF_EXTENDED	(1 << 4)
#define CLF_STRICT	(1 << 8)
#define CLF_LOCALE_USED (1 << 15)

typedef struct ClockFmtScnCmdArgs {
    void *clientData;  /* Opaque pointer to literal pool, etc. */
    Tcl_Interp *interp;	    /* Tcl interpreter */

    Tcl_Obj *formatObj;	    /* Format */
    Tcl_Obj *localeObj;	    /* Name of the locale where the time will be expressed. */
    Tcl_Obj *timezoneObj;   /* Default time zone in which the time will be expressed */
    Tcl_Obj *baseObj;	    /* Base (scan and add) or clockValue (format) */
    int	     flags;	    /* Flags control scanning */

    Tcl_Obj *mcDictObj;	    /* Current dictionary of tcl::clock package for given localeObj*/
} ClockFmtScnCmdArgs;

/* Last-period cache for fast UTC to local and backwards conversion */
typedef struct ClockLastTZOffs {
    /* keys */
    Tcl_Obj    *timezoneObj;
    int		changeover;
    Tcl_WideInt localSeconds;
    Tcl_WideInt rangesVal[2];   /* Bounds for cached time zone offset */
    /* values */
    int		tzOffset;
    Tcl_Obj    *tzName;		/* Name (abbreviation) of this area in TZ */
} ClockLastTZOffs;

/*
 * Structure containing the client data for [clock]
 */

typedef struct ClockClientData {
    size_t    refCount;		/* Number of live references. */
    Tcl_Obj **literals;		/* Pool of object literals (common, locale independent). */
    Tcl_Obj **mcLiterals;	/* Msgcat object literals with mc-keys for search with locale. */
    Tcl_Obj **mcLitIdxs;	/* Msgcat object indices prefixed with _IDX_,
				 * used for quick dictionary search */

    Tcl_Obj *mcDicts;		/* Msgcat collection, contains weak pointers to locale
				 * catalogs, and owns it references (onetime referenced) */

    /* Cache for current clock parameters, imparted via "configure" */
    size_t lastTZEpoch;
    int currentYearCentury;
    int yearOfCenturySwitch;
    int validMinYear;
    int validMaxYear;
    double maxJDN;

    Tcl_Obj *systemTimeZone;
    Tcl_Obj *systemSetupTZData;
    Tcl_Obj *gmtSetupTimeZoneUnnorm;
    Tcl_Obj *gmtSetupTimeZone;
    Tcl_Obj *gmtSetupTZData;
    Tcl_Obj *gmtTZName;
    Tcl_Obj *lastSetupTimeZoneUnnorm;
    Tcl_Obj *lastSetupTimeZone;
    Tcl_Obj *lastSetupTZData;
    Tcl_Obj *prevSetupTimeZoneUnnorm;
    Tcl_Obj *prevSetupTimeZone;
    Tcl_Obj *prevSetupTZData;

    Tcl_Obj *defaultLocale;
    Tcl_Obj *defaultLocaleDict;
    Tcl_Obj *currentLocale;
    Tcl_Obj *currentLocaleDict;
    Tcl_Obj *lastUsedLocaleUnnorm;
    Tcl_Obj *lastUsedLocale;
    Tcl_Obj *lastUsedLocaleDict;
    Tcl_Obj *prevUsedLocaleUnnorm;
    Tcl_Obj *prevUsedLocale;
    Tcl_Obj *prevUsedLocaleDict;

    /* Cache for last base (last-second fast convert if base/tz not changed) */
    struct {
	Tcl_Obj *timezoneObj;
	TclDateFields date;
    } lastBase;

    /* Last-period cache for fast UTC to Local and backwards conversion */
    ClockLastTZOffs lastTZOffsCache[2];

    int defFlags;		    /* Default flags (from configure), ATM
				     * only CLF_VALIDATE supported */
} ClockClientData;

#define ClockDefaultYearCentury 2000
#define ClockDefaultCenturySwitch 38

/*
 * Clock scan and format facilities.
 */

#define CLOCK_FMT_SCN_STORAGE_GC_SIZE 32

#define CLOCK_MIN_TOK_CHAIN_BLOCK_SIZE 2

typedef struct ClockScanToken ClockScanToken;


typedef int ClockScanTokenProc(
	ClockFmtScnCmdArgs *opts,
	DateInfo *info,
	ClockScanToken *tok);


typedef enum _CLCKTOK_TYPE {
   CTOKT_INT = 1, CTOKT_WIDE, CTOKT_PARSER, CTOKT_SPACE, CTOKT_WORD, CTOKT_CHAR,
   CFMTT_PROC
} CLCKTOK_TYPE;

typedef struct ClockScanTokenMap {
    unsigned short int	type;
    unsigned short int	flags;
    unsigned short int	clearFlags;
    unsigned short int	minSize;
    unsigned short int	maxSize;
    unsigned short int	offs;
    ClockScanTokenProc *parser;
    const void	       *data;
} ClockScanTokenMap;

struct ClockScanToken {
    ClockScanTokenMap  *map;
    struct {
	const char *start;
	const char *end;
    } tokWord;
    unsigned short int	endDistance;
    unsigned short int	lookAhMin;
    unsigned short int	lookAhMax;
    unsigned short int	lookAhTok;
};


#define MIN_FMT_RESULT_BLOCK_ALLOC 80
#define MIN_FMT_RESULT_BLOCK_DELTA 0
/* Maximal permitted threshold (buffer size > result size) in percent,
 * to directly return the buffer without reallocate */
#define MAX_FMT_RESULT_THRESHOLD   2

typedef struct DateFormat {
    char *resMem;
    char *resEnd;
    char *output;

    TclDateFields date;

    Tcl_Obj *localeEra;
} DateFormat;

#define CLFMT_INCR	    (1 << 3)
#define CLFMT_DECR	    (1 << 4)
#define CLFMT_CALC	    (1 << 5)
#define CLFMT_LOCALE_INDX   (1 << 8)

typedef struct ClockFormatToken ClockFormatToken;

typedef int ClockFormatTokenProc(
	ClockFmtScnCmdArgs *opts,
	DateFormat *dateFmt,
	ClockFormatToken *tok,
	int *val);

typedef struct ClockFormatTokenMap {
    unsigned short int	type;
    const char	       *tostr;
    unsigned short int	width;
    unsigned short int	flags;
    unsigned short int	divider;
    unsigned short int	divmod;
    unsigned short int	offs;
    ClockFormatTokenProc *fmtproc;
    void	       *data;
} ClockFormatTokenMap;

struct ClockFormatToken {
    ClockFormatTokenMap *map;
    struct {
	const char *start;
	const char *end;
    } tokWord;
};


typedef struct ClockFmtScnStorage ClockFmtScnStorage;

struct ClockFmtScnStorage {
    int			 objRefCount;	/* Reference count shared across threads */
    ClockScanToken	*scnTok;
    unsigned int	 scnTokC;
    unsigned int	 scnSpaceCount; /* Count of mandatory spaces used in format */
    ClockFormatToken	*fmtTok;
    unsigned int	 fmtTokC;
#if CLOCK_FMT_SCN_STORAGE_GC_SIZE > 0
    ClockFmtScnStorage	*nextPtr;
    ClockFmtScnStorage	*prevPtr;
#endif
    size_t		 fmtMinAlloc;
#if 0
   +Tcl_HashEntry    hashEntry		/* ClockFmtScnStorage is a derivate of Tcl_HashEntry,
					 * stored by offset +sizeof(self) */
#endif
};

/*
 * Clock macros.
 */

/*
 * Extracts Julian day and seconds of the day from posix seconds (tm).
 */
#define ClockExtractJDAndSODFromSeconds(jd, sod, tm) \
    if (1) { \
	jd = (tm + JULIAN_SEC_POSIX_EPOCH); \
	if (jd >= SECONDS_PER_DAY || jd <= -SECONDS_PER_DAY) { \
	    jd /= SECONDS_PER_DAY; \
	    sod = (int)(tm % SECONDS_PER_DAY); \
	} else { \
	    sod = (int)jd, jd = 0; \
	} \
	if (sod < 0) { \
	    sod += SECONDS_PER_DAY; \
	    /* JD is affected, if switched into negative (avoid 24 hours difference) */ \
	    if (jd <= 0) { \
		jd--; \
	    } \
	} \
    }

/*
 * Prototypes of module functions.
 */

MODULE_SCOPE int    ToSeconds(int Hours, int Minutes,
			    int Seconds, MERIDIAN Meridian);
MODULE_SCOPE int    IsGregorianLeapYear(TclDateFields *);
MODULE_SCOPE void
		    GetJulianDayFromEraYearWeekDay(
			    TclDateFields *fields, int changeover);
MODULE_SCOPE void
		    GetJulianDayFromEraYearMonthDay(
			    TclDateFields *fields, int changeover);
MODULE_SCOPE void
		    GetJulianDayFromEraYearDay(
			    TclDateFields *fields, int changeover);
MODULE_SCOPE int    ConvertUTCToLocal(void *clientData, Tcl_Interp *,
			    TclDateFields *, Tcl_Obj *timezoneObj, int);
MODULE_SCOPE Tcl_Obj *
		    LookupLastTransition(Tcl_Interp *, Tcl_WideInt,
			    int, Tcl_Obj *const *, Tcl_WideInt *rangesVal);

MODULE_SCOPE int    TclClockFreeScan(Tcl_Interp *interp, DateInfo *info);

/* tclClock.c module declarations */

MODULE_SCOPE Tcl_Obj *
		    ClockSetupTimeZone(void *clientData,
		Tcl_Interp *interp, Tcl_Obj *timezoneObj);

MODULE_SCOPE Tcl_Obj *
		    ClockMCDict(ClockFmtScnCmdArgs *opts);
MODULE_SCOPE Tcl_Obj *
		    ClockMCGet(ClockFmtScnCmdArgs *opts, int mcKey);
MODULE_SCOPE Tcl_Obj *
		    ClockMCGetIdx(ClockFmtScnCmdArgs *opts, int mcKey);
MODULE_SCOPE int    ClockMCSetIdx(ClockFmtScnCmdArgs *opts, int mcKey,
			Tcl_Obj *valObj);

/* tclClockFmt.c module declarations */

MODULE_SCOPE Tcl_Obj*
		    ClockFrmObjGetLocFmtKey(Tcl_Interp *interp,
			Tcl_Obj *objPtr);

MODULE_SCOPE ClockFmtScnStorage *
		    Tcl_GetClockFrmScnFromObj(Tcl_Interp *interp,
			Tcl_Obj *objPtr);
MODULE_SCOPE Tcl_Obj *
		    ClockLocalizeFormat(ClockFmtScnCmdArgs *opts);

MODULE_SCOPE int    ClockScan(DateInfo *info,
			Tcl_Obj *strObj, ClockFmtScnCmdArgs *opts);

MODULE_SCOPE int    ClockFormat(DateFormat *dateFmt,
			ClockFmtScnCmdArgs *opts);

MODULE_SCOPE void   ClockFrmScnClearCaches(void);

#endif /* _TCLCLOCK_H */