C++ PG_RETURN_INT16函数代码示例

Datum
int2up(PG_FUNCTION_ARGS)
{
	int16		arg = PG_GETARG_INT16(0);

	PG_RETURN_INT16(arg);
}

Datum
int2not(PG_FUNCTION_ARGS)
{
	int16		arg1 = PG_GETARG_INT16(0);

	PG_RETURN_INT16(~arg1);
}

/*
 *		int2in			- converts "num" to short
 */
Datum
int2in(PG_FUNCTION_ARGS)
{
	char	   *num = PG_GETARG_CSTRING(0);

	PG_RETURN_INT16(pg_atoi(num, sizeof(int16), '\0'));
}

Datum
int2div(PG_FUNCTION_ARGS)
{
	int16		arg1 = PG_GETARG_INT16(0);
	int16		arg2 = PG_GETARG_INT16(1);
	int16		result;

	if (arg2 == 0)
		ereport(ERROR,
				(errcode(ERRCODE_DIVISION_BY_ZERO),
				 errmsg("division by zero")));

	result = arg1 / arg2;

	/*
	 * Overflow check.	The only possible overflow case is for arg1 =
	 * SHRT_MIN, arg2 = -1, where the correct result is -SHRT_MIN, which can't
	 * be represented on a two's-complement machine.  Most machines produce
	 * SHRT_MIN but it seems some produce zero.
	 */
	if (arg2 == -1 && arg1 < 0 && result <= 0)
		ereport(ERROR,
				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
				 errmsg("smallint out of range")));
	PG_RETURN_INT16(result);
}

/*
 *		int2recv			- converts external binary format to int2
 */
Datum
int2recv(PG_FUNCTION_ARGS)
{
	StringInfo	buf = (StringInfo) PG_GETARG_POINTER(0);

	PG_RETURN_INT16((int16) pq_getmsgint(buf, sizeof(int16)));
}

Datum
int2shl(PG_FUNCTION_ARGS)
{
	int16		arg1 = PG_GETARG_INT16(0);
	int32		arg2 = PG_GETARG_INT32(1);

	PG_RETURN_INT16(arg1 << arg2);
}

Datum
int2xor(PG_FUNCTION_ARGS)
{
	int16		arg1 = PG_GETARG_INT16(0);
	int16		arg2 = PG_GETARG_INT16(1);

	PG_RETURN_INT16(arg1 ^ arg2);
}

Datum
int2smaller(PG_FUNCTION_ARGS)
{
	int16		arg1 = PG_GETARG_INT16(0);
	int16		arg2 = PG_GETARG_INT16(1);

	PG_RETURN_INT16((arg1 < arg2) ? arg1 : arg2);
}

/*
 * Add a master standby.
 *
 * gp_add_master_standby(hostname, address)
 *
 * Args:
 *  hostname - as above
 *  address - as above
 *
 * Returns:
 *  dbid of the new standby
 */
Datum
gp_add_master_standby(PG_FUNCTION_ARGS)
{
	CdbComponentDatabaseInfo *master = NULL;
	Relation	gprel;
	Datum values[Natts_gp_segment_configuration];
	bool nulls[Natts_gp_segment_configuration];
	HeapTuple tuple;
	cqContext	cqc;
	cqContext  *pcqCtx = NULL;

	if (PG_ARGISNULL(0))
		elog(ERROR, "host name cannot be NULL");
	if (PG_ARGISNULL(1))
		elog(ERROR, "address cannot be NULL");

	mirroring_sanity_check(MASTER_ONLY | UTILITY_MODE,
						   "gp_add_master_standby");

	if (standby_exists())
		elog(ERROR, "only a single master standby may be defined");

	/* master */
	master = registration_order_get_dbinfo(MASTER_ORDER_ID);

	/* Lock exclusively to avoid concurrent changes */
	gprel = heap_open(GpSegmentConfigRelationId, AccessExclusiveLock);

	pcqCtx = caql_beginscan(
				caql_addrel(cqclr(&cqc), gprel),
				cql("INSERT INTO gp_segment_configuration ", NULL));

	MemSet(nulls, false, sizeof(nulls));

	values[Anum_gp_segment_configuration_registration_order - 1] = Int32GetDatum(STANDBY_ORDER_ID);
	values[Anum_gp_segment_configuration_role - 1] = CharGetDatum(SEGMENT_ROLE_STANDBY_CONFIG);
	values[Anum_gp_segment_configuration_status - 1] = CharGetDatum('u');
	values[Anum_gp_segment_configuration_port - 1] = Int32GetDatum(master->port);
	values[Anum_gp_segment_configuration_hostname - 1] = PG_GETARG_DATUM(0);
	values[Anum_gp_segment_configuration_address - 1] = PG_GETARG_DATUM(1);
	nulls[Anum_gp_segment_configuration_description - 1] = true;

	tuple = caql_form_tuple(pcqCtx, values, nulls);

	/* insert a new tuple */
	caql_insert(pcqCtx, tuple); /* implicit update of index as well */

	caql_endscan(pcqCtx);

	if(master)
		pfree(master);

	heap_close(gprel, NoLock);

	PG_RETURN_INT16(1);
}

Datum
int2um(PG_FUNCTION_ARGS)
{
	int16		arg = PG_GETARG_INT16(0);

	if (unlikely(arg == PG_INT16_MIN))
		ereport(ERROR,
				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
				 errmsg("smallint out of range")));
	PG_RETURN_INT16(-arg);
}

Datum
i4toi2(PG_FUNCTION_ARGS)
{
	int32		arg1 = PG_GETARG_INT32(0);

	if (arg1 < SHRT_MIN || arg1 > SHRT_MAX)
		ereport(ERROR,
				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
				 errmsg("smallint out of range")));

	PG_RETURN_INT16((int16) arg1);
}

Datum
int2mi(PG_FUNCTION_ARGS)
{
	int16		arg1 = PG_GETARG_INT16(0);
	int16		arg2 = PG_GETARG_INT16(1);
	int16		result;

	if (unlikely(pg_sub_s16_overflow(arg1, arg2, &result)))
		ereport(ERROR,
				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
				 errmsg("smallint out of range")));
	PG_RETURN_INT16(result);
}

Datum
int2abs(PG_FUNCTION_ARGS)
{
	int16		arg1 = PG_GETARG_INT16(0);
	int16		result;

	if (unlikely(arg1 == PG_INT16_MIN))
		ereport(ERROR,
				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
				 errmsg("smallint out of range")));
	result = (arg1 < 0) ? -arg1 : arg1;
	PG_RETURN_INT16(result);
}

Datum
int2div(PG_FUNCTION_ARGS)
{
	int16		arg1 = PG_GETARG_INT16(0);
	int16		arg2 = PG_GETARG_INT16(1);
	int16		result;

	if (arg2 == 0)
	{
		ereport(ERROR,
				(errcode(ERRCODE_DIVISION_BY_ZERO),
				 errmsg("division by zero")));
		/* ensure compiler realizes we mustn't reach the division (gcc bug) */
		PG_RETURN_NULL();
	}

	/*
	 * SHRT_MIN / -1 is problematic, since the result can't be represented on
	 * a two's-complement machine.  Some machines produce SHRT_MIN, some
	 * produce zero, some throw an exception.  We can dodge the problem by
	 * recognizing that division by -1 is the same as negation.
	 */
	if (arg2 == -1)
	{
		result = -arg1;
		/* overflow check (needed for SHRT_MIN) */
		if (arg1 != 0 && SAMESIGN(result, arg1))
			ereport(ERROR,
					(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
					 errmsg("smallint out of range")));
		PG_RETURN_INT16(result);
	}

	/* No overflow is possible */

	result = arg1 / arg2;

	PG_RETURN_INT16(result);
}

Datum
int2mod(PG_FUNCTION_ARGS)
{
	int16		arg1 = PG_GETARG_INT16(0);
	int16		arg2 = PG_GETARG_INT16(1);

	if (arg2 == 0)
		ereport(ERROR,
				(errcode(ERRCODE_DIVISION_BY_ZERO),
				 errmsg("division by zero")));
	/* No overflow is possible */

	PG_RETURN_INT16(arg1 % arg2);
}