Replace TupleTableSlot convention for whole-row variables and function

results with tuples as ordinary varlena Datums.  This commit does not
in itself do much for us, except eliminate the horrid memory leak
associated with evaluation of whole-row variables.  However, it lays the
groundwork for allowing composite types as table columns, and perhaps
some other useful features as well.  Per my proposal of a few days ago.

6 files changed, 25 insertions, 60 deletions

diff --git a/contrib/dblink/dblink.c b/contrib/dblink/dblink.c
index ac941598be..4a521a0fac 100644
--- a/contrib/dblink/dblink.c
+++ b/contrib/dblink/dblink.c
@@ -447,7 +447,6 @@ dblink_fetch(PG_FUNCTION_ARGS)
 	TupleDesc	tupdesc = NULL;
 	int			call_cntr;
 	int			max_calls;
-	TupleTableSlot *slot;
 	AttInMetadata *attinmeta;
 	char	   *msg;
 	PGresult   *res = NULL;
@@ -566,9 +565,10 @@ dblink_fetch(PG_FUNCTION_ARGS)
 
 		if (functyptype == 'c')
 			tupdesc = TypeGetTupleDesc(functypeid, NIL);
-		else if (functyptype == 'p' && functypeid == RECORDOID)
+		else if (functypeid == RECORDOID)
 		{
-			if (!rsinfo || !IsA(rsinfo, ReturnSetInfo))
+			if (!rsinfo || !IsA(rsinfo, ReturnSetInfo) ||
+				rsinfo->expectedDesc == NULL)
 				ereport(ERROR,
 						(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 						 errmsg("function returning record called in context "
@@ -582,8 +582,6 @@ dblink_fetch(PG_FUNCTION_ARGS)
 			elog(ERROR, "return type must be a row type");
 
 		/* store needed metadata for subsequent calls */
-		slot = TupleDescGetSlot(tupdesc);
-		funcctx->slot = slot;
 		attinmeta = TupleDescGetAttInMetadata(tupdesc);
 		funcctx->attinmeta = attinmeta;
 
@@ -599,8 +597,6 @@ dblink_fetch(PG_FUNCTION_ARGS)
 	call_cntr = funcctx->call_cntr;
 	max_calls = funcctx->max_calls;
 
-	slot = funcctx->slot;
-
 	res = (PGresult *) funcctx->user_fctx;
 	attinmeta = funcctx->attinmeta;
 	tupdesc = attinmeta->tupdesc;
@@ -626,7 +622,7 @@ dblink_fetch(PG_FUNCTION_ARGS)
 		tuple = BuildTupleFromCStrings(attinmeta, values);
 
 		/* make the tuple into a datum */
-		result = TupleGetDatum(slot, tuple);
+		result = HeapTupleGetDatum(tuple);
 
 		SRF_RETURN_NEXT(funcctx, result);
 	}
@@ -649,7 +645,6 @@ dblink_record(PG_FUNCTION_ARGS)
 	TupleDesc	tupdesc = NULL;
 	int			call_cntr;
 	int			max_calls;
-	TupleTableSlot *slot;
 	AttInMetadata *attinmeta;
 	char	   *msg;
 	PGresult   *res = NULL;
@@ -741,7 +736,7 @@ dblink_record(PG_FUNCTION_ARGS)
 			/* need a tuple descriptor representing one TEXT column */
 			tupdesc = CreateTemplateTupleDesc(1, false);
 			TupleDescInitEntry(tupdesc, (AttrNumber) 1, "status",
-							   TEXTOID, -1, 0, false);
+							   TEXTOID, -1, 0);
 
 			/*
 			 * and save a copy of the command status string to return as
@@ -776,9 +771,10 @@ dblink_record(PG_FUNCTION_ARGS)
 		{
 			if (functyptype == 'c')
 				tupdesc = TypeGetTupleDesc(functypeid, NIL);
-			else if (functyptype == 'p' && functypeid == RECORDOID)
+			else if (functypeid == RECORDOID)
 			{
-				if (!rsinfo || !IsA(rsinfo, ReturnSetInfo))
+				if (!rsinfo || !IsA(rsinfo, ReturnSetInfo) ||
+					rsinfo->expectedDesc == NULL)
 					ereport(ERROR,
 							(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 							 errmsg("function returning record called in context "
@@ -793,8 +789,6 @@ dblink_record(PG_FUNCTION_ARGS)
 		}
 
 		/* store needed metadata for subsequent calls */
-		slot = TupleDescGetSlot(tupdesc);
-		funcctx->slot = slot;
 		attinmeta = TupleDescGetAttInMetadata(tupdesc);
 		funcctx->attinmeta = attinmeta;
 
@@ -810,8 +804,6 @@ dblink_record(PG_FUNCTION_ARGS)
 	call_cntr = funcctx->call_cntr;
 	max_calls = funcctx->max_calls;
 
-	slot = funcctx->slot;
-
 	res = (PGresult *) funcctx->user_fctx;
 	attinmeta = funcctx->attinmeta;
 	tupdesc = attinmeta->tupdesc;
@@ -846,7 +838,7 @@ dblink_record(PG_FUNCTION_ARGS)
 		tuple = BuildTupleFromCStrings(attinmeta, values);
 
 		/* make the tuple into a datum */
-		result = TupleGetDatum(slot, tuple);
+		result = HeapTupleGetDatum(tuple);
 
 		SRF_RETURN_NEXT(funcctx, result);
 	}
@@ -925,7 +917,7 @@ dblink_exec(PG_FUNCTION_ARGS)
 		/* need a tuple descriptor representing one TEXT column */
 		tupdesc = CreateTemplateTupleDesc(1, false);
 		TupleDescInitEntry(tupdesc, (AttrNumber) 1, "status",
-						   TEXTOID, -1, 0, false);
+						   TEXTOID, -1, 0);
 
 		/*
 		 * and save a copy of the command status string to return as our
@@ -939,7 +931,7 @@ dblink_exec(PG_FUNCTION_ARGS)
 		/* need a tuple descriptor representing one TEXT column */
 		tupdesc = CreateTemplateTupleDesc(1, false);
 		TupleDescInitEntry(tupdesc, (AttrNumber) 1, "status",
-						   TEXTOID, -1, 0, false);
+						   TEXTOID, -1, 0);
 
 		/*
 		 * and save a copy of the command status string to return as our
@@ -978,7 +970,6 @@ dblink_get_pkey(PG_FUNCTION_ARGS)
 	FuncCallContext *funcctx;
 	int32		call_cntr;
 	int32		max_calls;
-	TupleTableSlot *slot;
 	AttInMetadata *attinmeta;
 	MemoryContext oldcontext;
 
@@ -1010,15 +1001,9 @@ dblink_get_pkey(PG_FUNCTION_ARGS)
 		 */
 		tupdesc = CreateTemplateTupleDesc(2, false);
 		TupleDescInitEntry(tupdesc, (AttrNumber) 1, "position",
-						   INT4OID, -1, 0, false);
+						   INT4OID, -1, 0);
 		TupleDescInitEntry(tupdesc, (AttrNumber) 2, "colname",
-						   TEXTOID, -1, 0, false);
-
-		/* allocate a slot for a tuple with this tupdesc */
-		slot = TupleDescGetSlot(tupdesc);
-
-		/* assign slot to function context */
-		funcctx->slot = slot;
+						   TEXTOID, -1, 0);
 
 		/*
 		 * Generate attribute metadata needed later to produce tuples from
@@ -1053,8 +1038,6 @@ dblink_get_pkey(PG_FUNCTION_ARGS)
 	call_cntr = funcctx->call_cntr;
 	max_calls = funcctx->max_calls;
 
-	slot = funcctx->slot;
-
 	results = (char **) funcctx->user_fctx;
 	attinmeta = funcctx->attinmeta;
 
@@ -1075,7 +1058,7 @@ dblink_get_pkey(PG_FUNCTION_ARGS)
 		tuple = BuildTupleFromCStrings(attinmeta, values);
 
 		/* make the tuple into a datum */
-		result = TupleGetDatum(slot, tuple);
+		result = HeapTupleGetDatum(tuple);
 
 		SRF_RETURN_NEXT(funcctx, result);
 	}
diff --git a/contrib/intagg/int_aggregate.c b/contrib/intagg/int_aggregate.c
index 2bb06ff73a..bd03f5c0c3 100644
--- a/contrib/intagg/int_aggregate.c
+++ b/contrib/intagg/int_aggregate.c
@@ -25,7 +25,6 @@
 #include "catalog/pg_proc.h"
 #include "catalog/pg_type.h"
 #include "executor/executor.h"
-#include "utils/sets.h"
 #include "utils/syscache.h"
 #include "access/tupmacs.h"
 #include "access/xact.h"
diff --git a/contrib/pgstattuple/pgstattuple.c b/contrib/pgstattuple/pgstattuple.c
index abc2249aed..ca08261856 100644
--- a/contrib/pgstattuple/pgstattuple.c
+++ b/contrib/pgstattuple/pgstattuple.c
@@ -1,5 +1,5 @@
 /*
- * $PostgreSQL: pgsql/contrib/pgstattuple/pgstattuple.c,v 1.13 2003/11/29 19:51:35 pgsql Exp $
+ * $PostgreSQL: pgsql/contrib/pgstattuple/pgstattuple.c,v 1.14 2004/04/01 21:28:43 tgl Exp $
  *
  * Copyright (c) 2001,2002	Tatsuo Ishii
  *
@@ -111,7 +111,6 @@ pgstattuple_real(Relation rel)
 	uint64		free_space = 0; /* free/reusable space in bytes */
 	double		free_percent;	/* free/reusable space in % */
 	TupleDesc	tupdesc;
-	TupleTableSlot *slot;
 	AttInMetadata *attinmeta;
 	char	  **values;
 	int			i;
@@ -122,9 +121,6 @@ pgstattuple_real(Relation rel)
 	 */
 	tupdesc = RelationNameGetTupleDesc(DUMMY_TUPLE);
 
-	/* allocate a slot for a tuple with this tupdesc */
-	slot = TupleDescGetSlot(tupdesc);
-
 	/*
 	 * Generate attribute metadata needed later to produce tuples from raw
 	 * C strings
@@ -192,7 +188,7 @@ pgstattuple_real(Relation rel)
 	}
 
 	/*
-	 * Prepare a values array for storage in our slot. This should be an
+	 * Prepare a values array for constructing the tuple. This should be an
 	 * array of C strings which will be processed later by the appropriate
 	 * "in" functions.
 	 */
@@ -214,7 +210,7 @@ pgstattuple_real(Relation rel)
 	tuple = BuildTupleFromCStrings(attinmeta, values);
 
 	/* make the tuple into a datum */
-	result = TupleGetDatum(slot, tuple);
+	result = HeapTupleGetDatum(tuple);
 
 	/* Clean up */
 	for (i = 0; i < NCOLUMNS; i++)
diff --git a/contrib/tablefunc/tablefunc.c b/contrib/tablefunc/tablefunc.c
index 622164b91b..3eccebf476 100644
--- a/contrib/tablefunc/tablefunc.c
+++ b/contrib/tablefunc/tablefunc.c
@@ -351,7 +351,6 @@ crosstab(PG_FUNCTION_ARGS)
 	TupleDesc	ret_tupdesc;
 	int			call_cntr;
 	int			max_calls;
-	TupleTableSlot *slot;
 	AttInMetadata *attinmeta;
 	SPITupleTable *spi_tuptable = NULL;
 	TupleDesc	spi_tupdesc;
@@ -429,10 +428,10 @@ crosstab(PG_FUNCTION_ARGS)
 
 		if (functyptype == 'c')
 		{
-			/* Build a tuple description for a functypeid tuple */
+			/* Build a tuple description for a named composite type */
 			tupdesc = TypeGetTupleDesc(functypeid, NIL);
 		}
-		else if (functyptype == 'p' && functypeid == RECORDOID)
+		else if (functypeid == RECORDOID)
 		{
 			if (fcinfo->nargs != 2)
 				ereport(ERROR,
@@ -461,12 +460,6 @@ crosstab(PG_FUNCTION_ARGS)
 					 errmsg("return and sql tuple descriptions are " \
 							"incompatible")));
 
-		/* allocate a slot for a tuple with this tupdesc */
-		slot = TupleDescGetSlot(tupdesc);
-
-		/* assign slot to function context */
-		funcctx->slot = slot;
-
 		/*
 		 * Generate attribute metadata needed later to produce tuples from
 		 * raw C strings
@@ -499,9 +492,6 @@ crosstab(PG_FUNCTION_ARGS)
 	call_cntr = funcctx->call_cntr;
 	max_calls = funcctx->max_calls;
 
-	/* return slot for our tuple */
-	slot = funcctx->slot;
-
 	/* user context info */
 	fctx = (crosstab_fctx *) funcctx->user_fctx;
 	lastrowid = fctx->lastrowid;
@@ -621,7 +611,7 @@ crosstab(PG_FUNCTION_ARGS)
 				tuple = BuildTupleFromCStrings(attinmeta, values);
 
 				/* make the tuple into a datum */
-				result = TupleGetDatum(slot, tuple);
+				result = HeapTupleGetDatum(tuple);
 
 				/* Clean up */
 				for (i = 0; i < num_categories + 1; i++)
@@ -1675,7 +1665,7 @@ make_crosstab_tupledesc(TupleDesc spi_tupdesc, int num_categories)
 	strcpy(attname, "rowname");
 
 	TupleDescInitEntry(tupdesc, attnum, attname, sql_atttypid,
-					   -1, 0, false);
+					   -1, 0);
 
 	/* now the category values columns */
 	sql_attr = spi_tupdesc->attrs[2];
@@ -1687,7 +1677,7 @@ make_crosstab_tupledesc(TupleDesc spi_tupdesc, int num_categories)
 
 		sprintf(attname, "category_%d", i + 1);
 		TupleDescInitEntry(tupdesc, attnum, attname, sql_atttypid,
-						   -1, 0, false);
+						   -1, 0);
 	}
 
 	return tupdesc;
diff --git a/contrib/tsearch2/ts_stat.c b/contrib/tsearch2/ts_stat.c
index 732f25b6bd..a6518e3439 100644
--- a/contrib/tsearch2/ts_stat.c
+++ b/contrib/tsearch2/ts_stat.c
@@ -303,7 +303,6 @@ ts_setup_firstcall(FuncCallContext *funcctx, tsstat * stat)
 	memcpy(st->stat, stat, stat->len);
 	funcctx->user_fctx = (void *) st;
 	tupdesc = RelationNameGetTupleDesc("statinfo");
-	funcctx->slot = TupleDescGetSlot(tupdesc);
 	funcctx->attinmeta = TupleDescGetAttInMetadata(tupdesc);
 	MemoryContextSwitchTo(oldcontext);
 }
@@ -334,7 +333,7 @@ ts_process_call(FuncCallContext *funcctx)
 		(values[0])[entry->len] = '\0';
 
 		tuple = BuildTupleFromCStrings(funcctx->attinmeta, values);
-		result = TupleGetDatum(funcctx->slot, tuple);
+		result = HeapTupleGetDatum(tuple);
 
 		pfree(values[0]);
 		st->cur++;
diff --git a/contrib/tsearch2/wparser.c b/contrib/tsearch2/wparser.c
index b7e45e5188..9c3c443048 100644
--- a/contrib/tsearch2/wparser.c
+++ b/contrib/tsearch2/wparser.c
@@ -187,7 +187,6 @@ setup_firstcall(FuncCallContext *funcctx, Oid prsid)
 		);
 	funcctx->user_fctx = (void *) st;
 	tupdesc = RelationNameGetTupleDesc("tokentype");
-	funcctx->slot = TupleDescGetSlot(tupdesc);
 	funcctx->attinmeta = TupleDescGetAttInMetadata(tupdesc);
 	MemoryContextSwitchTo(oldcontext);
 }
@@ -211,7 +210,7 @@ process_call(FuncCallContext *funcctx)
 		values[2] = st->list[st->cur].descr;
 
 		tuple = BuildTupleFromCStrings(funcctx->attinmeta, values);
-		result = TupleGetDatum(funcctx->slot, tuple);
+		result = HeapTupleGetDatum(tuple);
 
 		pfree(values[1]);
 		pfree(values[2]);
@@ -391,7 +390,6 @@ prs_setup_firstcall(FuncCallContext *funcctx, int prsid, text *txt)
 
 	funcctx->user_fctx = (void *) st;
 	tupdesc = RelationNameGetTupleDesc("tokenout");
-	funcctx->slot = TupleDescGetSlot(tupdesc);
 	funcctx->attinmeta = TupleDescGetAttInMetadata(tupdesc);
 	MemoryContextSwitchTo(oldcontext);
 }
@@ -413,7 +411,7 @@ prs_process_call(FuncCallContext *funcctx)
 		sprintf(tid, "%d", st->list[st->cur].type);
 		values[1] = st->list[st->cur].lexem;
 		tuple = BuildTupleFromCStrings(funcctx->attinmeta, values);
-		result = TupleGetDatum(funcctx->slot, tuple);
+		result = HeapTupleGetDatum(tuple);
 
 		pfree(values[1]);
 		st->cur++;