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.

1 files changed, 26 insertions, 4 deletions

diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c
index 5c302e18d39..85ad6ffe788 100644
--- a/src/backend/utils/cache/relcache.c
+++ b/src/backend/utils/cache/relcache.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/cache/relcache.c,v 1.200 2004/03/16 05:05:58 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/cache/relcache.c,v 1.201 2004/04/01 21:28:45 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -63,6 +63,7 @@
 #include "utils/lsyscache.h"
 #include "utils/relcache.h"
 #include "utils/syscache.h"
+#include "utils/typcache.h"
 
 
 /*
@@ -432,7 +433,10 @@ RelationBuildTupleDesc(RelationBuildDescInfo buildinfo,
 	AttrDefault *attrdef = NULL;
 	int			ndef = 0;
 
-	relation->rd_att->tdhasoid = RelationGetForm(relation)->relhasoids;
+	/* copy some fields from pg_class row to rd_att */
+	relation->rd_att->tdtypeid = relation->rd_rel->reltype;
+	relation->rd_att->tdtypmod = -1;	/* unnecessary, but... */
+	relation->rd_att->tdhasoid = relation->rd_rel->relhasoids;
 
 	constr = (TupleConstr *) MemoryContextAlloc(CacheMemoryContext,
 												sizeof(TupleConstr));
@@ -1312,9 +1316,12 @@ formrdesc(const char *relationName,
 	 * Unlike the case with the relation tuple, this data had better be right
 	 * because it will never be replaced.  The input values must be
 	 * correctly defined by macros in src/include/catalog/ headers.
+	 *
+	 * Note however that rd_att's tdtypeid, tdtypmod, tdhasoid fields are
+	 * not right at this point.  They will be fixed later when the real
+	 * pg_class row is loaded.
 	 */
-	relation->rd_att = CreateTemplateTupleDesc(natts,
-										   relation->rd_rel->relhasoids);
+	relation->rd_att = CreateTemplateTupleDesc(natts, false);
 
 	/*
 	 * initialize tuple desc info
@@ -1595,6 +1602,7 @@ RelationReloadClassinfo(Relation relation)
 static void
 RelationClearRelation(Relation relation, bool rebuild)
 {
+	Oid			old_reltype = relation->rd_rel->reltype;
 	MemoryContext oldcxt;
 
 	/*
@@ -1679,6 +1687,7 @@ RelationClearRelation(Relation relation, bool rebuild)
 	if (!rebuild)
 	{
 		/* ok to zap remaining substructure */
+		flush_rowtype_cache(old_reltype);
 		FreeTupleDesc(relation->rd_att);
 		if (relation->rd_rulescxt)
 			MemoryContextDelete(relation->rd_rulescxt);
@@ -1704,6 +1713,7 @@ RelationClearRelation(Relation relation, bool rebuild)
 		if (RelationBuildDesc(buildinfo, relation) != relation)
 		{
 			/* Should only get here if relation was deleted */
+			flush_rowtype_cache(old_reltype);
 			FreeTupleDesc(old_att);
 			if (old_rulescxt)
 				MemoryContextDelete(old_rulescxt);
@@ -1715,11 +1725,15 @@ RelationClearRelation(Relation relation, bool rebuild)
 		relation->rd_isnew = old_isnew;
 		if (equalTupleDescs(old_att, relation->rd_att))
 		{
+			/* needn't flush typcache here */
 			FreeTupleDesc(relation->rd_att);
 			relation->rd_att = old_att;
 		}
 		else
+		{
+			flush_rowtype_cache(old_reltype);
 			FreeTupleDesc(old_att);
+		}
 		if (equalRuleLocks(old_rules, relation->rd_rules))
 		{
 			if (relation->rd_rulescxt)
@@ -2329,6 +2343,12 @@ RelationCacheInitializePhase2(void)
 			 */
 			Assert(relation->rd_rel != NULL);
 			memcpy((char *) relation->rd_rel, (char *) relp, CLASS_TUPLE_SIZE);
+
+			/*
+			 * Also update the derived fields in rd_att.
+			 */
+			relation->rd_att->tdtypeid = relp->reltype;
+			relation->rd_att->tdtypmod = -1;	/* unnecessary, but... */
 			relation->rd_att->tdhasoid = relp->relhasoids;
 
 			ReleaseSysCache(htup);
@@ -2918,6 +2938,8 @@ load_relcache_init_file(void)
 		/* initialize attribute tuple forms */
 		rel->rd_att = CreateTemplateTupleDesc(relform->relnatts,
 											  relform->relhasoids);
+		rel->rd_att->tdtypeid = relform->reltype;
+		rel->rd_att->tdtypmod = -1;			/* unnecessary, but... */
 
 		/* next read all the attribute tuple form data entries */
 		has_not_null = false;