Mega-commit to make heap_open/heap_openr/heap_close take an

additional argument specifying the kind of lock to acquire/release (or
'NoLock' to do no lock processing).  Ensure that all relations are locked
with some appropriate lock level before being examined --- this ensures
that relevant shared-inval messages have been processed and should prevent
problems caused by concurrent VACUUM.  Fix several bugs having to do with
mismatched increment/decrement of relation ref count and mismatched
heap_open/close (which amounts to the same thing).  A bogus ref count on
a relation doesn't matter much *unless* a SI Inval message happens to
arrive at the wrong time, which is probably why we got away with this
sloppiness for so long.  Repair missing grab of AccessExclusiveLock in
DROP TABLE, ALTER/RENAME TABLE, etc, as noted by Hiroshi.
Recommend 'make clean all' after pulling this update; I modified the
Relation struct layout slightly.
Will post further discussion to pghackers list shortly.

5 files changed, 41 insertions, 55 deletions

diff --git a/src/backend/parser/analyze.c b/src/backend/parser/analyze.c
index 2c4d1c7a7e8..276d28b3aa1 100644
--- a/src/backend/parser/analyze.c
+++ b/src/backend/parser/analyze.c
@@ -5,7 +5,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- *	$Id: analyze.c,v 1.118 1999/08/21 03:48:55 tgl Exp $
+ *	$Id: analyze.c,v 1.119 1999/09/18 19:07:12 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -64,7 +64,7 @@ parse_analyze(List *pl, ParseState *parentParseState)
 
 		parsetree = transformStmt(pstate, lfirst(pl));
 		if (pstate->p_target_relation != NULL)
-			heap_close(pstate->p_target_relation);
+			heap_close(pstate->p_target_relation, AccessShareLock);
 		pstate->p_target_relation = NULL;
 		pstate->p_target_rangetblentry = NULL;
 
@@ -73,7 +73,7 @@ parse_analyze(List *pl, ParseState *parentParseState)
 			result = lappend(result,
 							 transformStmt(pstate, lfirst(extras_before)));
 			if (pstate->p_target_relation != NULL)
-				heap_close(pstate->p_target_relation);
+				heap_close(pstate->p_target_relation, AccessShareLock);
 			pstate->p_target_relation = NULL;
 			pstate->p_target_rangetblentry = NULL;
 			extras_before = lnext(extras_before);
@@ -86,7 +86,7 @@ parse_analyze(List *pl, ParseState *parentParseState)
 			result = lappend(result,
 							 transformStmt(pstate, lfirst(extras_after)));
 			if (pstate->p_target_relation != NULL)
-				heap_close(pstate->p_target_relation);
+				heap_close(pstate->p_target_relation, AccessShareLock);
 			pstate->p_target_relation = NULL;
 			pstate->p_target_rangetblentry = NULL;
 			extras_after = lnext(extras_after);
diff --git a/src/backend/parser/parse_clause.c b/src/backend/parser/parse_clause.c
index 234987fb5f0..bae53ebbd87 100644
--- a/src/backend/parser/parse_clause.c
+++ b/src/backend/parser/parse_clause.c
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_clause.c,v 1.44 1999/08/21 03:48:55 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_clause.c,v 1.45 1999/09/18 19:07:12 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -75,11 +75,11 @@ setTargetTable(ParseState *pstate, char *relname)
 
 	/* This could only happen for multi-action rules */
 	if (pstate->p_target_relation != NULL)
-		heap_close(pstate->p_target_relation);
+		heap_close(pstate->p_target_relation, AccessShareLock);
 
 	pstate->p_target_rangetblentry = rte;
-	pstate->p_target_relation = heap_open(rte->relid);
-	/* will close relation later */
+	pstate->p_target_relation = heap_open(rte->relid, AccessShareLock);
+	/* will close relation later, see analyze.c */
 }
 
 /*
diff --git a/src/backend/parser/parse_func.c b/src/backend/parser/parse_func.c
index 19a287d99e8..15e63f7c98f 100644
--- a/src/backend/parser/parse_func.c
+++ b/src/backend/parser/parse_func.c
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_func.c,v 1.54 1999/08/22 20:15:03 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_func.c,v 1.55 1999/09/18 19:07:12 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -139,7 +139,7 @@ agg_get_candidates(char *aggname,
 	fmgr_info(F_NAMEEQ, (FmgrInfo *) &aggKey[0].sk_func);
 	aggKey[0].sk_argument = NameGetDatum(aggname);
 
-	pg_aggregate_desc = heap_openr(AggregateRelationName);
+	pg_aggregate_desc = heap_openr(AggregateRelationName, AccessShareLock);
 	pg_aggregate_scan = heap_beginscan(pg_aggregate_desc,
 									   0,
 									   SnapshotSelf,	/* ??? */
@@ -159,7 +159,7 @@ agg_get_candidates(char *aggname,
 	}
 
 	heap_endscan(pg_aggregate_scan);
-	heap_close(pg_aggregate_desc);
+	heap_close(pg_aggregate_desc, AccessShareLock);
 
 	return ncandidates;
 }	/* agg_get_candidates() */
@@ -310,11 +310,11 @@ ParseFuncOrColumn(ParseState *pstate, char *funcname, List *fargs,
 			if (attisset)
 			{
 				toid = exprType(first_arg);
-				rd = heap_openr(typeidTypeName(toid));
+				rd = heap_openr(typeidTypeName(toid), NoLock);
 				if (RelationIsValid(rd))
 				{
 					relname = RelationGetRelationName(rd)->data;
-					heap_close(rd);
+					heap_close(rd, NoLock);
 				}
 				else
 					elog(ERROR, "Type '%s' is not a relation type",
@@ -646,7 +646,7 @@ func_get_candidates(char *funcname, int nargs)
 	CandidateList current_candidate;
 	int			i;
 
-	heapRelation = heap_openr(ProcedureRelationName);
+	heapRelation = heap_openr(ProcedureRelationName, AccessShareLock);
 	ScanKeyEntryInitialize(&skey,
 						   (bits16) 0x0,
 						   (AttrNumber) 1,
@@ -690,7 +690,7 @@ func_get_candidates(char *funcname, int nargs)
 
 	index_endscan(sd);
 	index_close(idesc);
-	heap_close(heapRelation);
+	heap_close(heapRelation, AccessShareLock);
 
 	return candidates;
 }
@@ -1086,7 +1086,7 @@ find_inheritors(Oid relid, Oid **supervec)
 	visited = DLNewList();
 
 
-	inhrel = heap_openr(InheritsRelationName);
+	inhrel = heap_openr(InheritsRelationName, AccessShareLock);
 	inhtupdesc = RelationGetDescr(inhrel);
 
 	/*
@@ -1140,12 +1140,12 @@ find_inheritors(Oid relid, Oid **supervec)
 
 		if (qentry != (SuperQE *) NULL)
 		{
-
 			/* save the type id, rather than the relation id */
-			if ((rd = heap_open(qentry->sqe_relid)) == (Relation) NULL)
+			rd = heap_open(qentry->sqe_relid, NoLock);
+			if (! RelationIsValid(rd))
 				elog(ERROR, "Relid %u does not exist", qentry->sqe_relid);
 			qentry->sqe_relid = typeTypeId(typenameType(RelationGetRelationName(rd)->data));
-			heap_close(rd);
+			heap_close(rd, NoLock);
 
 			DLAddTail(visited, qe);
 
@@ -1153,7 +1153,7 @@ find_inheritors(Oid relid, Oid **supervec)
 		}
 	} while (qentry != (SuperQE *) NULL);
 
-	heap_close(inhrel);
+	heap_close(inhrel, AccessShareLock);
 
 	if (nvisited > 0)
 	{
@@ -1370,16 +1370,13 @@ ParseComplexProjection(ParseState *pstate,
 					 */
 
 					/* add a tlist to the func node and return the Iter */
-					rd = heap_openr(typeidTypeName(argtype));
+					rd = heap_openr(typeidTypeName(argtype), NoLock);
 					if (RelationIsValid(rd))
 					{
 						relid = RelationGetRelid(rd);
-						heap_close(rd);
-					}
-					if (RelationIsValid(rd))
-					{
 						func->func_tlist = setup_tlist(funcname, argrelid);
 						iter->itertype = attnumTypeId(rd, attnum);
+						heap_close(rd, NoLock);
 						return (Node *) iter;
 					}
 					else
@@ -1427,16 +1424,12 @@ ParseComplexProjection(ParseState *pstate,
 				{
 
 					/* add a tlist to the func node */
-					rd = heap_openr(typeidTypeName(argtype));
-					if (RelationIsValid(rd))
-					{
-						relid = RelationGetRelid(rd);
-						heap_close(rd);
-					}
+					rd = heap_openr(typeidTypeName(argtype), NoLock);
 					if (RelationIsValid(rd))
 					{
 						Expr	   *newexpr;
 
+						relid = RelationGetRelid(rd);
 						funcnode->func_tlist = setup_tlist(funcname, argrelid);
 						funcnode->functype = attnumTypeId(rd, attnum);
 
@@ -1446,8 +1439,11 @@ ParseComplexProjection(ParseState *pstate,
 						newexpr->oper = (Node *) funcnode;
 						newexpr->args = expr->args;
 
+						heap_close(rd, NoLock);
+
 						return (Node *) newexpr;
 					}
+					/* XXX why not an error condition if it's not there? */
 
 				}
 
@@ -1461,18 +1457,19 @@ ParseComplexProjection(ParseState *pstate,
 				 * If the Param is a complex type, this could be a
 				 * projection
 				 */
-				rd = heap_openr(typeidTypeName(param->paramtype));
+				rd = heap_openr(typeidTypeName(param->paramtype), NoLock);
 				if (RelationIsValid(rd))
 				{
 					relid = RelationGetRelid(rd);
-					heap_close(rd);
 					if ((attnum = get_attnum(relid, funcname))
 						!= InvalidAttrNumber)
 					{
 						param->paramtype = attnumTypeId(rd, attnum);
 						param->param_tlist = setup_tlist(funcname, relid);
+						heap_close(rd, NoLock);
 						return (Node *) param;
 					}
+					heap_close(rd, NoLock);
 				}
 				break;
 			}
diff --git a/src/backend/parser/parse_oper.c b/src/backend/parser/parse_oper.c
index 8f82e58517d..5a5c8709969 100644
--- a/src/backend/parser/parse_oper.c
+++ b/src/backend/parser/parse_oper.c
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_oper.c,v 1.31 1999/08/26 04:59:15 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_oper.c,v 1.32 1999/09/18 19:07:12 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -75,7 +75,6 @@ binary_oper_get_candidates(char *opname,
 	HeapScanDesc pg_operator_scan;
 	HeapTuple	tup;
 	Form_pg_operator oper;
-	int			nkeys;
 	int			ncandidates = 0;
 	ScanKeyData opKey[3];
 
@@ -91,13 +90,11 @@ binary_oper_get_candidates(char *opname,
 						   F_CHAREQ,
 						   CharGetDatum('b'));
 
-	nkeys = 2;
-
-	pg_operator_desc = heap_openr(OperatorRelationName);
+	pg_operator_desc = heap_openr(OperatorRelationName, AccessShareLock);
 	pg_operator_scan = heap_beginscan(pg_operator_desc,
 									  0,
 									  SnapshotSelf,		/* ??? */
-									  nkeys,
+									  2,
 									  opKey);
 
 	while (HeapTupleIsValid(tup = heap_getnext(pg_operator_scan, 0)))
@@ -114,7 +111,7 @@ binary_oper_get_candidates(char *opname,
 	}
 
 	heap_endscan(pg_operator_scan);
-	heap_close(pg_operator_desc);
+	heap_close(pg_operator_desc, AccessShareLock);
 
 	return ncandidates;
 }	/* binary_oper_get_candidates() */
@@ -522,7 +519,7 @@ unary_oper_get_candidates(char *op,
 	fmgr_info(F_CHAREQ, (FmgrInfo *) &opKey[1].sk_func);
 	opKey[1].sk_argument = CharGetDatum(rightleft);
 
-	pg_operator_desc = heap_openr(OperatorRelationName);
+	pg_operator_desc = heap_openr(OperatorRelationName, AccessShareLock);
 	pg_operator_scan = heap_beginscan(pg_operator_desc,
 									  0,
 									  SnapshotSelf,		/* ??? */
@@ -545,7 +542,7 @@ unary_oper_get_candidates(char *op,
 	}
 
 	heap_endscan(pg_operator_scan);
-	heap_close(pg_operator_desc);
+	heap_close(pg_operator_desc, AccessShareLock);
 
 	return ncandidates;
 }	/* unary_oper_get_candidates() */
diff --git a/src/backend/parser/parse_relation.c b/src/backend/parser/parse_relation.c
index 79b08635f02..af18087aa58 100644
--- a/src/backend/parser/parse_relation.c
+++ b/src/backend/parser/parse_relation.c
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_relation.c,v 1.26 1999/07/19 00:26:20 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_relation.c,v 1.27 1999/09/18 19:07:12 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -202,14 +202,9 @@ addRangeTableEntry(ParseState *pstate,
 	rte->relname = pstrdup(relname);
 	rte->refname = pstrdup(refname);
 
-	relation = heap_openr(relname);
-	if (relation == NULL)
-		elog(ERROR, "%s: %s",
-			 relname, aclcheck_error_strings[ACLCHECK_NO_CLASS]);
-
+	relation = heap_openr(relname, AccessShareLock);
 	rte->relid = RelationGetRelid(relation);
-
-	heap_close(relation);
+	heap_close(relation, AccessShareLock);
 
 	/*
 	 * Flags - zero or more from inheritance,union,version or recursive
@@ -246,10 +241,7 @@ expandAll(ParseState *pstate, char *relname, char *refname, int *this_resno)
 	if (rte == NULL)
 		rte = addRangeTableEntry(pstate, relname, refname, FALSE, FALSE);
 
-	rel = heap_open(rte->relid);
-	if (rel == NULL)
-		elog(ERROR, "Unable to expand all -- heap_open failed on %s",
-			 rte->refname);
+	rel = heap_open(rte->relid, AccessShareLock);
 
 	maxattrs = RelationGetNumberOfAttributes(rel);
 
@@ -278,7 +270,7 @@ expandAll(ParseState *pstate, char *relname, char *refname, int *this_resno)
 		te_list = lappend(te_list, te);
 	}
 
-	heap_close(rel);
+	heap_close(rel, AccessShareLock);
 
 	return te_list;
 }