regress.c

PostgreSQL7.4.6 for Linux

	{
		xid = &fd17a_xid;
		level = &fd17a_level;
		recursion = &fd17a_recursion;
		when = "AFTER ";
	}

	if (!TransactionIdIsCurrentTransactionId(*xid))
	{
		*xid = GetCurrentTransactionId();
		*level = 0;
		*recursion = true;
	}

	if (*level == 17)
	{
		*recursion = false;
		return PointerGetDatum(tuple);
	}

	if (!(*recursion))
		return PointerGetDatum(tuple);

	(*level)++;

	SPI_connect();

	fieldval = SPI_getvalue(tuple, tupdesc, 1);
	fieldtype = SPI_gettype(tupdesc, 1);

	query = (char *) palloc(100 + NAMEDATALEN * 3 +
							strlen(fieldval) + strlen(fieldtype));

	sprintf(query, "insert into %s select * from %s where %s = '%s'::%s",
			SPI_getrelname(rel), SPI_getrelname(rel),
			SPI_fname(tupdesc, 1),
			fieldval, fieldtype);

	if ((ret = SPI_exec(query, 0)) < 0)
		elog(ERROR, "funny_dup17 (fired %s) on level %3d: SPI_exec (insert ...) returned %d",
			 when, *level, ret);

	inserted = SPI_processed;

	sprintf(query, "select count (*) from %s where %s = '%s'::%s",
			SPI_getrelname(rel),
			SPI_fname(tupdesc, 1),
			fieldval, fieldtype);

	if ((ret = SPI_exec(query, 0)) < 0)
		elog(ERROR, "funny_dup17 (fired %s) on level %3d: SPI_exec (select ...) returned %d",
			 when, *level, ret);

	if (SPI_processed > 0)
	{
		selected = DatumGetInt32(DirectFunctionCall1(int4in,
											CStringGetDatum(SPI_getvalue(
												   SPI_tuptable->vals[0],
												   SPI_tuptable->tupdesc,
																		 1
																	))));
	}

	elog(DEBUG4, "funny_dup17 (fired %s) on level %3d: %d/%d tuples inserted/selected",
		 when, *level, inserted, selected);

	SPI_finish();

	(*level)--;

	if (*level == 0)
		*xid = InvalidTransactionId;

	return PointerGetDatum(tuple);
}

extern Datum ttdummy(PG_FUNCTION_ARGS);
extern Datum set_ttdummy(PG_FUNCTION_ARGS);

#define TTDUMMY_INFINITY	999999

static void *splan = NULL;
static bool ttoff = false;

PG_FUNCTION_INFO_V1(ttdummy);

Datum
ttdummy(PG_FUNCTION_ARGS)
{
	TriggerData *trigdata = (TriggerData *) fcinfo->context;
	Trigger    *trigger;		/* to get trigger name */
	char	  **args;			/* arguments */
	int			attnum[2];		/* fnumbers of start/stop columns */
	Datum		oldon,
				oldoff;
	Datum		newon,
				newoff;
	Datum	   *cvals;			/* column values */
	char	   *cnulls;			/* column nulls */
	char	   *relname;		/* triggered relation name */
	Relation	rel;			/* triggered relation */
	HeapTuple	trigtuple;
	HeapTuple	newtuple = NULL;
	HeapTuple	rettuple;
	TupleDesc	tupdesc;		/* tuple description */
	int			natts;			/* # of attributes */
	bool		isnull;			/* to know is some column NULL or not */
	int			ret;
	int			i;

	if (!CALLED_AS_TRIGGER(fcinfo))
		elog(ERROR, "ttdummy: not fired by trigger manager");
	if (TRIGGER_FIRED_FOR_STATEMENT(trigdata->tg_event))
		elog(ERROR, "ttdummy: can't process STATEMENT events");
	if (TRIGGER_FIRED_AFTER(trigdata->tg_event))
		elog(ERROR, "ttdummy: must be fired before event");
	if (TRIGGER_FIRED_BY_INSERT(trigdata->tg_event))
		elog(ERROR, "ttdummy: can't process INSERT event");
	if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
		newtuple = trigdata->tg_newtuple;

	trigtuple = trigdata->tg_trigtuple;

	rel = trigdata->tg_relation;
	relname = SPI_getrelname(rel);

	/* check if TT is OFF for this relation */
	if (ttoff)					/* OFF - nothing to do */
	{
		pfree(relname);
		return PointerGetDatum((newtuple != NULL) ? newtuple : trigtuple);
	}

	trigger = trigdata->tg_trigger;

	if (trigger->tgnargs != 2)
		elog(ERROR, "ttdummy (%s): invalid (!= 2) number of arguments %d",
			 relname, trigger->tgnargs);

	args = trigger->tgargs;
	tupdesc = rel->rd_att;
	natts = tupdesc->natts;

	for (i = 0; i < 2; i++)
	{
		attnum[i] = SPI_fnumber(tupdesc, args[i]);
		if (attnum[i] < 0)
			elog(ERROR, "ttdummy (%s): there is no attribute %s", relname, args[i]);
		if (SPI_gettypeid(tupdesc, attnum[i]) != INT4OID)
			elog(ERROR, "ttdummy (%s): attributes %s and %s must be of abstime type",
				 relname, args[0], args[1]);
	}

	oldon = SPI_getbinval(trigtuple, tupdesc, attnum[0], &isnull);
	if (isnull)
		elog(ERROR, "ttdummy (%s): %s must be NOT NULL", relname, args[0]);

	oldoff = SPI_getbinval(trigtuple, tupdesc, attnum[1], &isnull);
	if (isnull)
		elog(ERROR, "ttdummy (%s): %s must be NOT NULL", relname, args[1]);

	if (newtuple != NULL)		/* UPDATE */
	{
		newon = SPI_getbinval(newtuple, tupdesc, attnum[0], &isnull);
		if (isnull)
			elog(ERROR, "ttdummy (%s): %s must be NOT NULL", relname, args[0]);
		newoff = SPI_getbinval(newtuple, tupdesc, attnum[1], &isnull);
		if (isnull)
			elog(ERROR, "ttdummy (%s): %s must be NOT NULL", relname, args[1]);

		if (oldon != newon || oldoff != newoff)
			elog(ERROR, "ttdummy (%s): you can't change %s and/or %s columns (use set_ttdummy)",
				 relname, args[0], args[1]);

		if (newoff != TTDUMMY_INFINITY)
		{
			pfree(relname);		/* allocated in upper executor context */
			return PointerGetDatum(NULL);
		}
	}
	else if (oldoff != TTDUMMY_INFINITY)		/* DELETE */
	{
		pfree(relname);
		return PointerGetDatum(NULL);
	}

	{
		text	   *seqname = DatumGetTextP(DirectFunctionCall1(textin,
										CStringGetDatum("ttdummy_seq")));

		newoff = DirectFunctionCall1(nextval,
									 PointerGetDatum(seqname));
		/* nextval now returns int64; coerce down to int32 */
		newoff = Int32GetDatum((int32) DatumGetInt64(newoff));
		pfree(seqname);
	}

	/* Connect to SPI manager */
	if ((ret = SPI_connect()) < 0)
		elog(ERROR, "ttdummy (%s): SPI_connect returned %d", relname, ret);

	/* Fetch tuple values and nulls */
	cvals = (Datum *) palloc(natts * sizeof(Datum));
	cnulls = (char *) palloc(natts * sizeof(char));
	for (i = 0; i < natts; i++)
	{
		cvals[i] = SPI_getbinval((newtuple != NULL) ? newtuple : trigtuple,
								 tupdesc, i + 1, &isnull);
		cnulls[i] = (isnull) ? 'n' : ' ';
	}

	/* change date column(s) */
	if (newtuple)				/* UPDATE */
	{
		cvals[attnum[0] - 1] = newoff;	/* start_date eq current date */
		cnulls[attnum[0] - 1] = ' ';
		cvals[attnum[1] - 1] = TTDUMMY_INFINITY;		/* stop_date eq INFINITY */
		cnulls[attnum[1] - 1] = ' ';
	}
	else
/* DELETE */
	{
		cvals[attnum[1] - 1] = newoff;	/* stop_date eq current date */
		cnulls[attnum[1] - 1] = ' ';
	}

	/* if there is no plan ... */
	if (splan == NULL)
	{
		void	   *pplan;
		Oid		   *ctypes;
		char	   *query;

		/* allocate space in preparation */
		ctypes = (Oid *) palloc(natts * sizeof(Oid));
		query = (char *) palloc(100 + 16 * natts);

		/*
		 * Construct query: INSERT INTO _relation_ VALUES ($1, ...)
		 */
		sprintf(query, "INSERT INTO %s VALUES (", relname);
		for (i = 1; i <= natts; i++)
		{
			sprintf(query + strlen(query), "$%d%s",
					i, (i < natts) ? ", " : ")");
			ctypes[i - 1] = SPI_gettypeid(tupdesc, i);
		}

		/* Prepare plan for query */
		pplan = SPI_prepare(query, natts, ctypes);
		if (pplan == NULL)
			elog(ERROR, "ttdummy (%s): SPI_prepare returned %d", relname, SPI_result);

		pplan = SPI_saveplan(pplan);
		if (pplan == NULL)
			elog(ERROR, "ttdummy (%s): SPI_saveplan returned %d", relname, SPI_result);

		splan = pplan;
	}

	ret = SPI_execp(splan, cvals, cnulls, 0);

	if (ret < 0)
		elog(ERROR, "ttdummy (%s): SPI_execp returned %d", relname, ret);

	/* Tuple to return to upper Executor ... */
	if (newtuple)				/* UPDATE */
	{
		HeapTuple	tmptuple;

		tmptuple = SPI_copytuple(trigtuple);
		rettuple = SPI_modifytuple(rel, tmptuple, 1, &(attnum[1]), &newoff, NULL);
		SPI_freetuple(tmptuple);
	}
	else
/* DELETE */
		rettuple = trigtuple;

	SPI_finish();				/* don't forget say Bye to SPI mgr */

	pfree(relname);

	return PointerGetDatum(rettuple);
}

PG_FUNCTION_INFO_V1(set_ttdummy);

Datum
set_ttdummy(PG_FUNCTION_ARGS)
{
	int32		on = PG_GETARG_INT32(0);

	if (ttoff)					/* OFF currently */
	{
		if (on == 0)
			PG_RETURN_INT32(0);

		/* turn ON */
		ttoff = false;
		PG_RETURN_INT32(0);
	}

	/* ON currently */
	if (on != 0)
		PG_RETURN_INT32(1);

	/* turn OFF */
	ttoff = true;

	PG_RETURN_INT32(1);
}


/*
 * Type int44 has no real-world use, but the regression tests use it.
 * It's a four-element vector of int4's.
 */

/*
 *		int44in			- converts "num num ..." to internal form
 *
 *		Note: Fills any missing positions with zeroes.
 */
PG_FUNCTION_INFO_V1(int44in);

Datum
int44in(PG_FUNCTION_ARGS)
{
	char	   *input_string = PG_GETARG_CSTRING(0);
	int32	   *result = (int32 *) palloc(4 * sizeof(int32));
	int			i;

	i = sscanf(input_string,
			   "%d, %d, %d, %d",
			   &result[0],
			   &result[1],
			   &result[2],
			   &result[3]);
	while (i < 4)
		result[i++] = 0;

	PG_RETURN_POINTER(result);
}

/*
 *		int44out		- converts internal form to "num num ..."
 */
PG_FUNCTION_INFO_V1(int44out);

Datum
int44out(PG_FUNCTION_ARGS)
{
	int32	   *an_array = (int32 *) PG_GETARG_POINTER(0);
	char	   *result = (char *) palloc(16 * 4);		/* Allow 14 digits +
														 * sign */
	int			i;
	char	   *walk;

	walk = result;
	for (i = 0; i < 4; i++)
	{
		pg_ltoa(an_array[i], walk);
		while (*++walk != '\0')
			;
		*walk++ = ' ';
	}
	*--walk = '\0';
	PG_RETURN_CSTRING(result);
}