timestamp.c

postgresql8.3.4源码,开源数据库

	result = timestamp;

	AdjustTimestampForTypmod(&result, typmod);

	PG_RETURN_TIMESTAMPTZ(result);
}


/* interval_in()
 * Convert a string to internal form.
 *
 * External format(s):
 *	Uses the generic date/time parsing and decoding routines.
 */
Datum
interval_in(PG_FUNCTION_ARGS)
{
	char	   *str = PG_GETARG_CSTRING(0);

#ifdef NOT_USED
	Oid			typelem = PG_GETARG_OID(1);
#endif
	int32		typmod = PG_GETARG_INT32(2);
	Interval   *result;
	fsec_t		fsec;
	struct pg_tm tt,
			   *tm = &tt;
	int			dtype;
	int			nf;
	int			dterr;
	char	   *field[MAXDATEFIELDS];
	int			ftype[MAXDATEFIELDS];
	char		workbuf[256];

	tm->tm_year = 0;
	tm->tm_mon = 0;
	tm->tm_mday = 0;
	tm->tm_hour = 0;
	tm->tm_min = 0;
	tm->tm_sec = 0;
	fsec = 0;

	dterr = ParseDateTime(str, workbuf, sizeof(workbuf), field,
						  ftype, MAXDATEFIELDS, &nf);
	if (dterr == 0)
		dterr = DecodeInterval(field, ftype, nf, &dtype, tm, &fsec);
	if (dterr != 0)
	{
		if (dterr == DTERR_FIELD_OVERFLOW)
			dterr = DTERR_INTERVAL_OVERFLOW;
		DateTimeParseError(dterr, str, "interval");
	}

	result = (Interval *) palloc(sizeof(Interval));

	switch (dtype)
	{
		case DTK_DELTA:
			if (tm2interval(tm, fsec, result) != 0)
				ereport(ERROR,
						(errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
						 errmsg("interval out of range")));
			break;

		case DTK_INVALID:
			ereport(ERROR,
					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
			  errmsg("date/time value \"%s\" is no longer supported", str)));
			break;

		default:
			elog(ERROR, "unexpected dtype %d while parsing interval \"%s\"",
				 dtype, str);
	}

	AdjustIntervalForTypmod(result, typmod);

	PG_RETURN_INTERVAL_P(result);
}

/* interval_out()
 * Convert a time span to external form.
 */
Datum
interval_out(PG_FUNCTION_ARGS)
{
	Interval   *span = PG_GETARG_INTERVAL_P(0);
	char	   *result;
	struct pg_tm tt,
			   *tm = &tt;
	fsec_t		fsec;
	char		buf[MAXDATELEN + 1];

	if (interval2tm(*span, tm, &fsec) != 0)
		elog(ERROR, "could not convert interval to tm");

	if (EncodeInterval(tm, fsec, DateStyle, buf) != 0)
		elog(ERROR, "could not format interval");

	result = pstrdup(buf);
	PG_RETURN_CSTRING(result);
}

/*
 *		interval_recv			- converts external binary format to interval
 */
Datum
interval_recv(PG_FUNCTION_ARGS)
{
	StringInfo	buf = (StringInfo) PG_GETARG_POINTER(0);

#ifdef NOT_USED
	Oid			typelem = PG_GETARG_OID(1);
#endif
	int32		typmod = PG_GETARG_INT32(2);
	Interval   *interval;

	interval = (Interval *) palloc(sizeof(Interval));

#ifdef HAVE_INT64_TIMESTAMP
	interval->time = pq_getmsgint64(buf);
#else
	interval->time = pq_getmsgfloat8(buf);
#endif
	interval->day = pq_getmsgint(buf, sizeof(interval->day));
	interval->month = pq_getmsgint(buf, sizeof(interval->month));

	AdjustIntervalForTypmod(interval, typmod);

	PG_RETURN_INTERVAL_P(interval);
}

/*
 *		interval_send			- converts interval to binary format
 */
Datum
interval_send(PG_FUNCTION_ARGS)
{
	Interval   *interval = PG_GETARG_INTERVAL_P(0);
	StringInfoData buf;

	pq_begintypsend(&buf);
#ifdef HAVE_INT64_TIMESTAMP
	pq_sendint64(&buf, interval->time);
#else
	pq_sendfloat8(&buf, interval->time);
#endif
	pq_sendint(&buf, interval->day, sizeof(interval->day));
	pq_sendint(&buf, interval->month, sizeof(interval->month));
	PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
}

Datum
intervaltypmodin(PG_FUNCTION_ARGS)
{
	ArrayType  *ta = PG_GETARG_ARRAYTYPE_P(0);
	int32	   *tl;
	int			n;
	int32		typmod;

	tl = ArrayGetIntegerTypmods(ta, &n);

	/*
	 * tl[0] - opt_interval tl[1] - Iconst (optional)
	 *
	 * Note we must validate tl[0] even though it's normally guaranteed
	 * correct by the grammar --- consider SELECT 'foo'::"interval"(1000).
	 */
	if (n > 0)
	{
		switch (tl[0])
		{
			case INTERVAL_MASK(YEAR):
			case INTERVAL_MASK(MONTH):
			case INTERVAL_MASK(DAY):
			case INTERVAL_MASK(HOUR):
			case INTERVAL_MASK(MINUTE):
			case INTERVAL_MASK(SECOND):
			case INTERVAL_MASK(YEAR) | INTERVAL_MASK(MONTH):
			case INTERVAL_MASK(DAY) | INTERVAL_MASK(HOUR):
			case INTERVAL_MASK(DAY) | INTERVAL_MASK(HOUR) | INTERVAL_MASK(MINUTE):
			case INTERVAL_MASK(DAY) | INTERVAL_MASK(HOUR) | INTERVAL_MASK(MINUTE) | INTERVAL_MASK(SECOND):
			case INTERVAL_MASK(HOUR) | INTERVAL_MASK(MINUTE):
			case INTERVAL_MASK(HOUR) | INTERVAL_MASK(MINUTE) | INTERVAL_MASK(SECOND):
			case INTERVAL_MASK(MINUTE) | INTERVAL_MASK(SECOND):
			case INTERVAL_FULL_RANGE:
				/* all OK */
				break;
			default:
				ereport(ERROR,
						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
						 errmsg("invalid INTERVAL type modifier")));
		}
	}

	if (n == 1)
	{
		if (tl[0] != INTERVAL_FULL_RANGE)
			typmod = INTERVAL_TYPMOD(INTERVAL_FULL_PRECISION, tl[0]);
		else
			typmod = -1;
	}
	else if (n == 2)
	{
		if (tl[1] < 0)
			ereport(ERROR,
					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
					 errmsg("INTERVAL(%d) precision must not be negative",
							tl[1])));
		if (tl[1] > MAX_INTERVAL_PRECISION)
		{
			ereport(WARNING,
					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
			  errmsg("INTERVAL(%d) precision reduced to maximum allowed, %d",
					 tl[1], MAX_INTERVAL_PRECISION)));
			typmod = INTERVAL_TYPMOD(MAX_INTERVAL_PRECISION, tl[0]);
		}
		else
			typmod = INTERVAL_TYPMOD(tl[1], tl[0]);
	}
	else
	{
		ereport(ERROR,
				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
				 errmsg("invalid INTERVAL type modifier")));
		typmod = 0;				/* keep compiler quiet */
	}

	PG_RETURN_INT32(typmod);
}

Datum
intervaltypmodout(PG_FUNCTION_ARGS)
{
	int32		typmod = PG_GETARG_INT32(0);
	char	   *res = (char *) palloc(64);
	int			fields;
	int			precision;
	const char *fieldstr;

	if (typmod < 0)
	{
		*res = '\0';
		PG_RETURN_CSTRING(res);
	}

	fields = INTERVAL_RANGE(typmod);
	precision = INTERVAL_PRECISION(typmod);

	switch (fields)
	{
		case INTERVAL_MASK(YEAR):
			fieldstr = " year";
			break;
		case INTERVAL_MASK(MONTH):
			fieldstr = " month";
			break;
		case INTERVAL_MASK(DAY):
			fieldstr = " day";
			break;
		case INTERVAL_MASK(HOUR):
			fieldstr = " hour";
			break;
		case INTERVAL_MASK(MINUTE):
			fieldstr = " minute";
			break;
		case INTERVAL_MASK(SECOND):
			fieldstr = " second";
			break;
		case INTERVAL_MASK(YEAR) | INTERVAL_MASK(MONTH):
			fieldstr = " year to month";
			break;
		case INTERVAL_MASK(DAY) | INTERVAL_MASK(HOUR):
			fieldstr = " day to hour";
			break;
		case INTERVAL_MASK(DAY) | INTERVAL_MASK(HOUR) | INTERVAL_MASK(MINUTE):
			fieldstr = " day to minute";
			break;
		case INTERVAL_MASK(DAY) | INTERVAL_MASK(HOUR) | INTERVAL_MASK(MINUTE) | INTERVAL_MASK(SECOND):
			fieldstr = " day to second";
			break;
		case INTERVAL_MASK(HOUR) | INTERVAL_MASK(MINUTE):
			fieldstr = " hour to minute";
			break;
		case INTERVAL_MASK(HOUR) | INTERVAL_MASK(MINUTE) | INTERVAL_MASK(SECOND):
			fieldstr = " hour to second";
			break;
		case INTERVAL_MASK(MINUTE) | INTERVAL_MASK(SECOND):
			fieldstr = " minute to second";
			break;
		case INTERVAL_FULL_RANGE:
			fieldstr = "";
			break;
		default:
			elog(ERROR, "invalid INTERVAL typmod: 0x%x", typmod);
			fieldstr = "";
			break;
	}

	if (precision != INTERVAL_FULL_PRECISION)
		snprintf(res, 64, "(%d)%s", precision, fieldstr);
	else
		snprintf(res, 64, "%s", fieldstr);

	PG_RETURN_CSTRING(res);
}


/* interval_scale()
 * Adjust interval type for specified fields.
 * Used by PostgreSQL type system to stuff columns.
 */
Datum
interval_scale(PG_FUNCTION_ARGS)
{
	Interval   *interval = PG_GETARG_INTERVAL_P(0);
	int32		typmod = PG_GETARG_INT32(1);
	Interval   *result;

	result = palloc(sizeof(Interval));
	*result = *interval;

	AdjustIntervalForTypmod(result, typmod);

	PG_RETURN_INTERVAL_P(result);
}

/*
 *	Adjust interval for specified precision, in both YEAR to SECOND
 *	range and sub-second precision.
 */
static void
AdjustIntervalForTypmod(Interval *interval, int32 typmod)
{
#ifdef HAVE_INT64_TIMESTAMP
	static const int64 IntervalScales[MAX_INTERVAL_PRECISION + 1] = {
		INT64CONST(1000000),
		INT64CONST(100000),
		INT64CONST(10000),
		INT64CONST(1000),
		INT64CONST(100),
		INT64CONST(10),
		INT64CONST(1)
	};

	static const int64 IntervalOffsets[MAX_INTERVAL_PRECISION + 1] = {
		INT64CONST(500000),
		INT64CONST(50000),
		INT64CONST(5000),
		INT64CONST(500),
		INT64CONST(50),
		INT64CONST(5),
		INT64CONST(0)
	};
#else
	static const double IntervalScales[MAX_INTERVAL_PRECISION + 1] = {
		1,
		10,
		100,
		1000,
		10000,
		100000,
		1000000
	};
#endif

	/*
	 * Unspecified range and precision? Then not necessary to adjust. Setting
	 * typmod to -1 is the convention for all types.
	 */
	if (typmod != -1)
	{
		int			range = INTERVAL_RANGE(typmod);
		int			precision = INTERVAL_PRECISION(typmod);

		if (range == INTERVAL_FULL_RANGE)
		{
			/* Do nothing... */
		}
		else if (range == INTERVAL_MASK(YEAR))
		{
			interval->month = (interval->month / MONTHS_PER_YEAR) * MONTHS_PER_YEAR;
			interval->day = 0;
			interval->time = 0;
		}
		else if (range == INTERVAL_MASK(MONTH))
		{
			interval->month %= MONTHS_PER_YEAR;
			interval->day = 0;
			interval->time = 0;
		}
		/* YEAR TO MONTH */
		else if (range == (INTERVAL_MASK(YEAR) | INTERVAL_MASK(MONTH)))
		{
			/* month is already year to month */
			interval->day = 0;
			interval->time = 0;
		}
		else if (range == INTERVAL_MASK(DAY))
		{
			interval->month = 0;
			interval->time = 0;
		}
		else if (range == INTERVAL_MASK(HOUR))
		{
			interval->month = 0;
			interval->day = 0;

#ifdef HAVE_INT64_TIMESTAMP
			interval->time = (interval->time / USECS_PER_HOUR) *
				USECS_PER_HOUR;
#else
			interval->time = ((int) (interval->time / SECS_PER_HOUR)) * (double) SECS_PER_HOUR;
#endif
		}
		else if (range == INTERVAL_MASK(MINUTE))
		{
#ifdef HAVE_INT64_TIMESTAMP
			int64		hour;
#else
			double		hour;
#endif

			interval->month = 0;
			interval->day = 0;

#ifdef HAVE_INT64_TIMESTAMP
			hour = interval->time / USECS_PER_HOUR;
			interval->time -= hour * USECS_PER_HOUR;
			interval->time = (interval->time / USECS_PER_MINUTE) *
				USECS_PER_MINUTE;
#else
			TMODULO(interval->time, hour, (double) SECS_PER_HOUR);
			interval->time = ((int) (interval->time / SECS_PER_MINUTE)) * (double) SECS_PER_MINUTE;
#endif
		}
		else if (range == INTERVAL_MASK(SECOND))
		{
#ifdef HAVE_INT64_TIMESTAMP
			int64		minute;
#else
			double		minute;
#endif

			interval->month = 0;
			interval->day = 0;

#ifdef HAVE_INT64_TIMESTAMP
			minute = interval->time / USECS_PER_MINUTE;
			interval->time -= minute * USECS_PER_MINUTE;
#else
			TMODULO(interval->time, minute, (double) SECS_PER_MINUTE);
			/* return subseconds too */
#endif
		}
		/* DAY TO HOUR */
		else if (range == (INTERVAL_MASK(DAY) |
						   INTERVAL_MASK(HOUR)))
		{
			interval->month = 0;

#ifdef HAVE_INT64_TIMESTAMP
			interval->time = (interval->time / USECS_PER_HOUR) *
				USECS_PER_HOUR;
#else
			interval->time = ((int) (interval->time / SECS_PER_HOUR)) * (double) SECS_PER_HOUR;
#endif
		}
		/* DAY TO MINUTE */
		else if (range == (INTERVAL_MASK(DAY) |
						   INTERVAL_MASK(HOUR) |
						   INTERVAL_MASK(MINUTE)))
		{
			interval->month = 0;

#ifdef HAVE_INT64_TIMESTAMP
			interval->time = (interval->time / USECS_PER_MINUTE) *
				USECS_PER_MINUTE;
#else
			interval->time = ((int) (interval->time / SECS_PER_MINUTE)) * (double) SECS_PER_MINUTE;
#endif
		}
		/* DAY TO SECOND */
		else if (range == (INTERVAL_MASK(DAY) |
						   INTERVAL_MASK(HOUR) |
						   INTERVAL_MASK(MINUTE) |
						   INTERVAL_MASK(SECOND)))
			interval->month = 0;

		/* HOUR TO MINUTE */
		else if (range == (INTERVAL_MASK(HOUR) |
						   INTERVAL_MASK(MINUTE)))
		{
			interval->month = 0;
			interval->day = 0;

#ifdef HAVE_INT64_TIMESTAMP
			interval->time = (interval->time / USECS_PER_MINUTE) *
				USECS_PER_MINUTE;
#else
			interval->time = ((int) (interval->time / SECS_PER_MINUTE)) * (double) SECS_PER_MINUTE;
#endif
		}
		/* HOUR TO SECOND */
		else if (range == (INTERVAL_MASK(HOUR) |
						   INTERVAL_MASK(MINUTE) |
						   INTERVAL_MASK(SECOND)))
		{
			interval->month = 0;
			interval->day = 0;
			/* return subseconds too */
		}
		/* MINUTE TO SECOND */
		else if (range == (INTERVAL_MASK(MINUTE) |
						   INTERVAL_MASK(SECOND)))
		{
#ifdef HAVE_INT64_TIMESTAMP
			int64		hour;
#else
			double		hour;
#endif

			interval->month = 0;
			interval->day = 0;

#ifdef HAVE_INT64_TIMESTAMP
			hour = interval->time / USECS_PER_HOUR;
			interval->time -= hour * USECS_PER_HOUR;
#else
			TMODULO(interval->time, hour, (double) SECS_PER_HOUR);
#endif
		}
		else
			elog(ERROR, "unrecognized interval typmod: %d", typmod);

		/* Need to adjust subsecond precision? */
		if (precision != INTERVAL_FULL_PRECISION)
		{
			if (precision < 0 || precision > MAX_INTERVAL_PRECISION)
				ereport(ERROR,
						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
				   errmsg("interval(%d) precision must be between %d and %d",
						  precision, 0, MAX_INTERVAL_PRECISION)));

			/*
			 * Note: this round-to-nearest code is not completely consistent
			 * about rounding values that are exactly halfway between integral
			 * values.	On most platforms, rint() will implement
			 * round-to-nearest-even, but the integer code always rounds up
			 * (away from zero).  Is it worth trying to be consistent?
			 */
#ifdef HAVE_INT64_TIMESTAMP
			if (interval->time >= INT64CONST(0))
			{
				interval->time = ((interval->time +
								   IntervalOffsets[precision]) /
								  IntervalScales[precision]) *
					IntervalScales[precision];
			}
			else
			{
				interval->time = -(((-interval->time +