📄 dt.c

📁 关系型数据库 Postgresql 6.5.2
💻 C
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					*result = tm->tm_mon;					break;				case DTK_QUARTER:					*result = (tm->tm_mon / 4) + 1;					break;				case DTK_YEAR:					*result = tm->tm_year;					break;				case DTK_DECADE:					*result = (tm->tm_year / 10);					break;				case DTK_CENTURY:					*result = (tm->tm_year / 100);					break;				case DTK_MILLENIUM:					*result = (tm->tm_year / 1000);					break;				default:					elog(ERROR, "Datetime units '%s' not supported", lowunits);					*result = 0;			}		}		else if (type == RESERV)		{			switch (val)			{				case DTK_EPOCH:					DATETIME_EPOCH(*result);					*result = dt - SetDateTime(*result);					break;				case DTK_DOW:					if (datetime2tm(dt, &tz, tm, &fsec, &tzn) != 0)						elog(ERROR, "Unable to encode datetime", NULL);					*result = j2day(date2j(tm->tm_year, tm->tm_mon, tm->tm_mday));					break;				case DTK_DOY:					if (datetime2tm(dt, &tz, tm, &fsec, &tzn) != 0)						elog(ERROR, "Unable to encode datetime", NULL);					*result = (date2j(tm->tm_year, tm->tm_mon, tm->tm_mday)							   - date2j(tm->tm_year, 1, 1) + 1);					break;				default:					elog(ERROR, "Datetime units '%s' not supported", lowunits);					*result = 0;			}		}		else		{			elog(ERROR, "Datetime units '%s' not recognized", lowunits);			*result = 0;		}	}	return result;}	/* datetime_part() *//* timespan_part() * Extract specified field from timespan. */float64timespan_part(text *units, TimeSpan *timespan){	float64		result;	int			type,				val;	int			i;	char	   *up,			   *lp,				lowunits[MAXDATELEN + 1];	double		fsec;	struct tm	tt,			   *tm = &tt;	if ((!PointerIsValid(units)) || (!PointerIsValid(timespan)))		return NULL;	result = palloc(sizeof(float64data));	up = VARDATA(units);	lp = lowunits;	for (i = 0; i < (VARSIZE(units) - VARHDRSZ); i++)		*lp++ = tolower(*up++);	*lp = '\0';	type = DecodeUnits(0, lowunits, &val);	if (type == IGNORE)		type = DecodeSpecial(0, lowunits, &val);#ifdef DATEDEBUG	if (type == IGNORE)		strcpy(lowunits, "(unknown)");	printf("timespan_part- units %s type=%d value=%d\n", lowunits, type, val);#endif	if (TIMESPAN_IS_INVALID(*timespan))	{#if NOT_USED		elog(ERROR, "Timespan is not finite", NULL);#endif		*result = 0;	}	else if (type == UNITS)	{		if (timespan2tm(*timespan, tm, &fsec) == 0)		{			switch (val)			{				case DTK_MICROSEC:					*result = (fsec * 1000000);					break;				case DTK_MILLISEC:					*result = (fsec * 1000);					break;				case DTK_SECOND:					*result = (tm->tm_sec + fsec);					break;				case DTK_MINUTE:					*result = tm->tm_min;					break;				case DTK_HOUR:					*result = tm->tm_hour;					break;				case DTK_DAY:					*result = tm->tm_mday;					break;				case DTK_MONTH:					*result = tm->tm_mon;					break;				case DTK_QUARTER:					*result = (tm->tm_mon / 4) + 1;					break;				case DTK_YEAR:					*result = tm->tm_year;					break;				case DTK_DECADE:					*result = (tm->tm_year / 10);					break;				case DTK_CENTURY:					*result = (tm->tm_year / 100);					break;				case DTK_MILLENIUM:					*result = (tm->tm_year / 1000);					break;				default:					elog(ERROR, "Timespan units '%s' not yet supported", units);					result = NULL;			}		}		else		{			elog(NOTICE, "Timespan out of range", NULL);			*result = 0;		}	}	else if ((type == RESERV) && (val == DTK_EPOCH))	{		*result = timespan->time;		if (timespan->month != 0)		{			*result += ((365.25 * 86400) * (timespan->month / 12));			*result += ((30 * 86400) * (timespan->month % 12));		}	}	else	{		elog(ERROR, "Timespan units '%s' not recognized", units);		*result = 0;	}	return result;}	/* timespan_part() *//* datetime_zone() * Encode datetime type with specified time zone. */text *datetime_zone(text *zone, DateTime *datetime){	text	   *result;	DateTime	dt;	int			tz;	int			type,				val;	int			i;	char	   *up,			   *lp,				lowzone[MAXDATELEN + 1];	char	   *tzn,				upzone[MAXDATELEN + 1];	double		fsec;	struct tm	tt,			   *tm = &tt;	char		buf[MAXDATELEN + 1];	int			len;	if ((!PointerIsValid(zone)) || (!PointerIsValid(datetime)))		return NULL;	up = VARDATA(zone);	lp = lowzone;	for (i = 0; i < (VARSIZE(zone) - VARHDRSZ); i++)		*lp++ = tolower(*up++);	*lp = '\0';	type = DecodeSpecial(0, lowzone, &val);#ifdef DATEDEBUG	if (type == IGNORE)		strcpy(lowzone, "(unknown)");	printf("datetime_zone- zone %s type=%d value=%d\n", lowzone, type, val);#endif	if (DATETIME_NOT_FINITE(*datetime))	{		/*		 * could return null but Postgres doesn't like that currently. -		 * tgl 97/06/12		 */		elog(ERROR, "Datetime is not finite", NULL);		result = NULL;	}	else if ((type == TZ) || (type == DTZ))	{		tm->tm_isdst = ((type == DTZ) ? 1 : 0);		tz = val * 60;		dt = (DATETIME_IS_RELATIVE(*datetime) ? SetDateTime(*datetime) : *datetime);		dt = dt2local(dt, tz);		if (datetime2tm(dt, NULL, tm, &fsec, NULL) != 0)			elog(ERROR, "Datetime not legal", NULL);		up = upzone;		lp = lowzone;		for (i = 0; *lp != '\0'; i++)			*up++ = toupper(*lp++);		*up = '\0';		tzn = upzone;		EncodeDateTime(tm, fsec, &tz, &tzn, DateStyle, buf);		len = (strlen(buf) + VARHDRSZ);		result = palloc(len);		VARSIZE(result) = len;		memmove(VARDATA(result), buf, (len - VARHDRSZ));	}	else	{		elog(ERROR, "Time zone '%s' not recognized", lowzone);		result = NULL;	}	return result;}	/* datetime_zone() *//***************************************************************************** *	 PRIVATE ROUTINES														 * *****************************************************************************//* definitions for squeezing values into "value" */#define ABS_SIGNBIT		(char) 0200#define VALMASK			(char) 0177#define NEG(n)			((n)|ABS_SIGNBIT)#define SIGNEDCHAR(c)	((c)&ABS_SIGNBIT? -((c)&VALMASK): (c))#define FROMVAL(tp)		(-SIGNEDCHAR((tp)->value) * 10) /* uncompress */#define TOVAL(tp, v)	((tp)->value = ((v) < 0? NEG((-(v))/10): (v)/10))/* * to keep this table reasonably small, we divide the lexval for TZ and DTZ * entries by 10 and truncate the text field at MAXTOKLEN characters. * the text field is not guaranteed to be NULL-terminated. */static datetkn datetktbl[] = {/*		text			token	lexval */	{EARLY, RESERV, DTK_EARLY}, /* "-infinity" reserved for "early time" */	{"acsst", DTZ, 63},			/* Cent. Australia */	{"acst", TZ, 57},			/* Cent. Australia */	{DA_D, ADBC, AD},			/* "ad" for years >= 0 */	{"abstime", IGNORE, 0},		/* "abstime" for pre-v6.1 "Invalid								 * Abstime" */	{"adt", DTZ, NEG(18)},		/* Atlantic Daylight Time */	{"aesst", DTZ, 66},			/* E. Australia */	{"aest", TZ, 60},			/* Australia Eastern Std Time */	{"ahst", TZ, NEG(60)},		/* Alaska-Hawaii Std Time */	{"allballs", RESERV, DTK_ZULU},		/* 00:00:00 */	{"am", AMPM, AM},	{"apr", MONTH, 4},	{"april", MONTH, 4},	{"ast", TZ, NEG(24)},		/* Atlantic Std Time (Canada) */	{"at", IGNORE, 0},			/* "at" (throwaway) */	{"aug", MONTH, 8},	{"august", MONTH, 8},	{"awsst", DTZ, 54},			/* W. Australia */	{"awst", TZ, 48},			/* W. Australia */	{DB_C, ADBC, BC},			/* "bc" for years < 0 */	{"bst", TZ, 6},				/* British Summer Time */	{"bt", TZ, 18},				/* Baghdad Time */	{"cadt", DTZ, 63},			/* Central Australian DST */	{"cast", TZ, 57},			/* Central Australian ST */	{"cat", TZ, NEG(60)},		/* Central Alaska Time */	{"cct", TZ, 48},			/* China Coast */	{"cdt", DTZ, NEG(30)},		/* Central Daylight Time */	{"cet", TZ, 6},				/* Central European Time */	{"cetdst", DTZ, 12},		/* Central European Dayl.Time */	{"cst", TZ, NEG(36)},		/* Central Standard Time */	{DCURRENT, RESERV, DTK_CURRENT},	/* "current" is always now */	{"dec", MONTH, 12},	{"december", MONTH, 12},	{"dnt", TZ, 6},				/* Dansk Normal Tid */	{"dow", RESERV, DTK_DOW},	/* day of week */	{"doy", RESERV, DTK_DOY},	/* day of year */	{"dst", DTZMOD, 6},	{"east", TZ, NEG(60)},		/* East Australian Std Time */	{"edt", DTZ, NEG(24)},		/* Eastern Daylight Time */	{"eet", TZ, 12},			/* East. Europe, USSR Zone 1 */	{"eetdst", DTZ, 18},		/* Eastern Europe */	{EPOCH, RESERV, DTK_EPOCH}, /* "epoch" reserved for system epoch time */#if USE_AUSTRALIAN_RULES	{"est", TZ, 60},			/* Australia Eastern Std Time */#else	{"est", TZ, NEG(30)},		/* Eastern Standard Time */#endif	{"feb", MONTH, 2},	{"february", MONTH, 2},	{"fri", DOW, 5},	{"friday", DOW, 5},	{"fst", TZ, 6},				/* French Summer Time */	{"fwt", DTZ, 12},			/* French Winter Time  */	{"gmt", TZ, 0},				/* Greenwish Mean Time */	{"gst", TZ, 60},			/* Guam Std Time, USSR Zone 9 */	{"hdt", DTZ, NEG(54)},		/* Hawaii/Alaska */	{"hmt", DTZ, 18},			/* Hellas ? ? */	{"hst", TZ, NEG(60)},		/* Hawaii Std Time */	{"idle", TZ, 72},			/* Intl. Date Line, East */	{"idlw", TZ, NEG(72)},		/* Intl. Date Line, West */	{LATE, RESERV, DTK_LATE},	/* "infinity" reserved for "late time" */	{INVALID, RESERV, DTK_INVALID},	/* "invalid" reserved for invalid time */	{"ist", TZ, 12},			/* Israel */	{"it", TZ, 21},				/* Iran Time */	{"jan", MONTH, 1},	{"january", MONTH, 1},	{"jst", TZ, 54},			/* Japan Std Time,USSR Zone 8 */	{"jt", TZ, 45},				/* Java Time */	{"jul", MONTH, 7},	{"july", MONTH, 7},	{"jun", MONTH, 6},	{"june", MONTH, 6},	{"kst", TZ, 54},			/* Korea Standard Time */	{"ligt", TZ, 60},			/* From Melbourne, Australia */	{"mar", MONTH, 3},	{"march", MONTH, 3},	{"may", MONTH, 5},	{"mdt", DTZ, NEG(36)},		/* Mountain Daylight Time */	{"mest", DTZ, 12},			/* Middle Europe Summer Time */	{"met", TZ, 6},				/* Middle Europe Time */	{"metdst", DTZ, 12},		/* Middle Europe Daylight Time */	{"mewt", TZ, 6},			/* Middle Europe Winter Time */	{"mez", TZ, 6},				/* Middle Europe Zone */	{"mon", DOW, 1},	{"monday", DOW, 1},	{"mst", TZ, NEG(42)},		/* Mountain Standard Time */	{"mt", TZ, 51},				/* Moluccas Time */	{"ndt", DTZ, NEG(15)},		/* Nfld. Daylight Time */	{"nft", TZ, NEG(21)},		/* Newfoundland Standard Time */	{"nor", TZ, 6},				/* Norway Standard Time */	{"nov", MONTH, 11},	{"november", MONTH, 11},	{NOW, RESERV, DTK_NOW},		/* current transaction time */	{"nst", TZ, NEG(21)},		/* Nfld. Standard Time */	{"nt", TZ, NEG(66)},		/* Nome Time */	{"nzdt", DTZ, 78},			/* New Zealand Daylight Time */	{"nzst", TZ, 72},			/* New Zealand Standard Time */	{"nzt", TZ, 72},			/* New Zealand Time */	{"oct", MONTH, 10},	{"october", MONTH, 10},	{"on", IGNORE, 0},			/* "on" (throwaway) */	{"pdt", DTZ, NEG(42)},		/* Pacific Daylight Time */	{"pm", AMPM, PM},	{"pst", TZ, NEG(48)},		/* Pacific Standard Time */	{"sadt", DTZ, 63},			/* S. Australian Dayl. Time */	{"sast", TZ, 57},			/* South Australian Std Time */	{"sat", DOW, 6},	{"saturday", DOW, 6},	{"sep", MONTH, 9},	{"sept", MONTH, 9},	{"september", MONTH, 9},	{"set", TZ, NEG(6)},		/* Seychelles Time ?? */	{"sst", DTZ, 12},			/* Swedish Summer Time */	{"sun", DOW, 0},	{"sunday", DOW, 0},	{"swt", TZ, 6},				/* Swedish Winter Time	*/	{"thu", DOW, 4},	{"thur", DOW, 4},	{"thurs", DOW, 4},	{"thursday", DOW, 4},	{TODAY, RESERV, DTK_TODAY}, /* midnight */	{TOMORROW, RESERV, DTK_TOMORROW},	/* tomorrow midnight */	{"tue", DOW, 2},	{"tues", DOW, 2},	{"tuesday", DOW, 2},	{"undefined", RESERV, DTK_INVALID}, /* "undefined" pre-v6.1 invalid										 * time */	{"ut", TZ, 0},	{"utc", TZ, 0},	{"wadt", DTZ, 48},			/* West Australian DST */	{"wast", TZ, 42},			/* West Australian Std Time */	{"wat", TZ, NEG(6)},		/* West Africa Time */	{"wdt", DTZ, 54},			/* West Australian DST */	{"wed", DOW, 3},	{"wednesday", DOW, 3},	{"weds", DOW, 3},	{"wet", TZ, 0},				/* Western Europe */	{"wetdst", DTZ, 6},			/* Western Europe */	{"wst", TZ, 48},			/* West Australian Std Time */	{"ydt", DTZ, NEG(48)},		/* Yukon Daylight Time */	{YESTERDAY, RESERV, DTK_YESTERDAY}, /* yesterday midnight */	{"yst", TZ, NEG(54)},		/* Yukon Standard Time */	{"zp4", TZ, NEG(24)},		/* GMT +4  hours. */	{"zp5", TZ, NEG(30)},		/* GMT +5  hours. */	{"zp6", TZ, NEG(36)},		/* GMT +6  hours. */	{"z", RESERV, DTK_ZULU},	/* 00:00:00 */	{ZULU, RESERV, DTK_ZULU},	/* 00:00:00 */};static unsigned int szdatetktbl = sizeof datetktbl / sizeof datetktbl[0];static datetkn deltatktbl[] = {/*		text			token	lexval */	{"@", IGNORE, 0},			/* postgres relative time prefix */	{DAGO, AGO, 0},				/* "ago" indicates negative time offset */	{"c", UNITS, DTK_CENTURY},	/* "century" relative time units */	{"cent", UNITS, DTK_CENTURY},		/* "century" relative time units */	{"centuries", UNITS, DTK_CENTURY},	/* "centuries" relative time units */	{DCENTURY, UNITS, DTK_CENTURY},		/* "century" relative time units */	{"d", UNITS, DTK_DAY},		/* "day" relative time units */	{DDAY, UNITS, DTK_DAY},		/* "day" relative time units */	{"days", UNITS, DTK_DAY},	/* "days" relative time units */	{"dec", UNITS, DTK_DECADE}, /* "decade" relative time units */	{"decs", UNITS, DTK_DECADE},/* "decades" relative time units */	{DDECADE, UNITS, DTK_DECADE},		/* "decade" relative time units */	{"decades", UNITS, DTK_DECADE},		/* "decades" relative time units */	{"h", UNITS, DTK_HOUR},		/* "hour" relative time units */	{DHOUR, UNITS, DTK_HOUR},	/* "hour" relative time units */	{"hours", UNITS, DTK_HOUR}, /* "hours" relative time units */	{"hr", UNITS, DTK_HOUR},	/* "hour" relative time units */	{"hrs", UNITS, DTK_HOUR},	/* "hours" relative time units */	{INVALID, RESERV, DTK_INVALID},		/* "invalid" reserved for invalid										 * time */	{"m", UNITS, DTK_MINUTE},	/* "minute" relative time units */	{"microsecon", UNITS, DTK_MICROSEC},		/* "microsecond" relative												 * time units */	{"mil", UNITS, DTK_MILLENIUM},		/* "millenium" relative time units */	{"mils", UNITS, DTK_MILLENIUM},		/* "millenia" relative time units */	{"millenia", UNITS, DTK_MILLENIUM}, /* "millenia" relative time units */	{DMILLENIUM, UNITS, DTK_MILLENIUM}, /* "millenium" relative time units */	{"millisecon", UNITS, DTK_MILLISEC},		/* relative time units */	{"min", UNITS, DTK_MINUTE}, /* "minute" relative time units */	{"mins", UNITS, DTK_MINUTE},/* "minutes" relative time units */	{"mins", UNITS, DTK_MINUTE},/* "minutes" relative time units */	{DMINUTE, UNITS, DTK_MINUTE},		/* "minute" relative time units */	{"minutes", UNITS, DTK_MINUTE},		/* "minutes" relative time units */	{"mon", UNITS, DTK_MONTH},	/* "months" relative time units */	{"mons", UNITS, DTK_MONTH}, /* "months" relative time units */	{DMONTH, UNITS, DTK_MONTH}, /* "month" relative time units */	{"months", UNITS, DTK_MONTH},	{"ms", UNITS, DTK_MILLISEC},	{"msec", UNITS, DTK_MILLISEC},	{DMILLISEC, UNITS, DTK_MILLISEC},	{"mseconds", UNITS, DTK_MILLISEC},	{"msecs", UNITS, DTK_MILLISEC},	{"qtr", UNITS, DTK_QUARTER},/* "quarter" relative time */	{DQUARTER, UNITS, DTK_QUARTER},		/* "quarter" relative time */	{"reltime", IGNORE, 0},		/* for pre-v6.1 "Undefined Reltime" */	{"s", UNITS, DTK_SECOND},	{"sec", UNITS, DTK_SECOND},	{DSECOND, UNITS, DTK_SECOND},	{"seconds", UNITS, DTK_SECOND},	{"secs", UNITS, DTK_SECOND},	{DTIMEZONE, UNITS, DTK_TZ}, /* "timezone" time offset */	{"tz", UNITS, DTK_TZ},		/* "timezone" time offset */	{"tz_hour", UNITS, DTK_TZ_HOUR},	/* timezone hour units */	{"tz_minute", UNITS, DTK_TZ_MINUTE},		/* timezone minutes units */	{"undefined", RESERV, DTK_INVALID}, /* pre-v6.1 invalid time */	{"us", UNITS, DTK_MICROSEC},/* "microsecond" relative time units */	{"usec", UNITS, DTK_MICROSEC},		/* "microsecond" relative time										 * units */	{DMICROSEC, UNITS, DTK_MICROSEC},	/* "microsecond" relative time										 * units */	{"useconds", UNITS, DTK_MICROSEC},	/* "microseconds" relative time										 * units */	{"usecs", UNITS, DTK_MICROSEC},		/* "microseconds" relative time										 * units */	{"w", UNITS, DTK_WEEK},		/* "week" relative time units */	{DWEEK, UNITS, DTK_WEEK},	/* "week" relative time units */	{"weeks", UNITS, DTK_WEEK}, /* "weeks" relative time units */	{"y", UNITS, DTK_YEAR},		/* "year" relative time units */	{DYEAR, UNITS, DTK_YEAR},	/* "year" relative time units */	{"years", UNITS, DTK_YEAR}, /* "years" relative time units */	{"yr", UNITS, DTK_YEAR},	/* "year" relative time units */	{"yrs", UNITS, DTK_YEAR},	/* "years" relative time units */};static unsigned int szdeltatktbl = sizeof deltatktbl / sizeof deltatktbl[0];#if USE_DATE_CACHEdatetkn    *datecache[MAXDATEFIELDS] = {NULL};datetkn    *deltacache[MAXDATEFIELDS] = {NULL};#endif/* * Calendar time to Julian date conversions. * Julian date is commonly used in astronomical applications, *	since it is numerically accurate and computationally simple. * The algorithms here will accurately convert between Julian day *	and calendar date for all non-negative Julian days *	(i.e. from Nov 23, -4713 on). * * Ref: Explanatory Supplement to the Astronomical Almanac, 1992. *	University Science Books, 20 Edgehill Rd. Mill Valley CA 94941. * * Use the algorithm by Henry Fliegel, a former NASA/JPL colleague *	now at Aerospace Corp. (hi, Henry!) * * These routines will be used by other date/time packages - tgl 97/02/25 */int
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