refactor ALTER some-obj SET OWNER implementation

Remove duplicate implementation of catalog munging and miscellaneous
privilege and consistency checks.  Instead rely on already existing data
in objectaddress.c to do the work.

Author: KaiGai Kohei
Tweaked by me
Reviewed by Robert Haas

Author: alvherre

src/backend/catalog/pg_largeobject.c

@@ -139,108 +139,6 @@ LargeObjectDrop(Oid loid)
 	heap_close(pg_lo_meta, RowExclusiveLock);
 }
 
-/*
- * LargeObjectAlterOwner
- *
- * Implementation of ALTER LARGE OBJECT statement
- */
-void
-LargeObjectAlterOwner(Oid loid, Oid newOwnerId)
-{
-	Form_pg_largeobject_metadata form_lo_meta;
-	Relation	pg_lo_meta;
-	ScanKeyData skey[1];
-	SysScanDesc scan;
-	HeapTuple	oldtup;
-	HeapTuple	newtup;
-
-	pg_lo_meta = heap_open(LargeObjectMetadataRelationId,
-						   RowExclusiveLock);
-
-	ScanKeyInit(&skey[0],
-				ObjectIdAttributeNumber,
-				BTEqualStrategyNumber, F_OIDEQ,
-				ObjectIdGetDatum(loid));
-
-	scan = systable_beginscan(pg_lo_meta,
-							  LargeObjectMetadataOidIndexId, true,
-							  SnapshotNow, 1, skey);
-
-	oldtup = systable_getnext(scan);
-	if (!HeapTupleIsValid(oldtup))
-		ereport(ERROR,
-				(errcode(ERRCODE_UNDEFINED_OBJECT),
-				 errmsg("large object %u does not exist", loid)));
-
-	form_lo_meta = (Form_pg_largeobject_metadata) GETSTRUCT(oldtup);
-	if (form_lo_meta->lomowner != newOwnerId)
-	{
-		Datum		values[Natts_pg_largeobject_metadata];
-		bool		nulls[Natts_pg_largeobject_metadata];
-		bool		replaces[Natts_pg_largeobject_metadata];
-		Acl		   *newAcl;
-		Datum		aclDatum;
-		bool		isnull;
-
-		/* Superusers can always do it */
-		if (!superuser())
-		{
-			/*
-			 * lo_compat_privileges is not checked here, because ALTER LARGE
-			 * OBJECT ... OWNER did not exist at all prior to PostgreSQL 9.0.
-			 *
-			 * We must be the owner of the existing object.
-			 */
-			if (!pg_largeobject_ownercheck(loid, GetUserId()))
-				ereport(ERROR,
-						(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
-						 errmsg("must be owner of large object %u", loid)));
-
-			/* Must be able to become new owner */
-			check_is_member_of_role(GetUserId(), newOwnerId);
-		}
-
-		memset(values, 0, sizeof(values));
-		memset(nulls, false, sizeof(nulls));
-		memset(replaces, false, sizeof(nulls));
-
-		values[Anum_pg_largeobject_metadata_lomowner - 1]
-			= ObjectIdGetDatum(newOwnerId);
-		replaces[Anum_pg_largeobject_metadata_lomowner - 1] = true;
-
-		/*
-		 * Determine the modified ACL for the new owner. This is only
-		 * necessary when the ACL is non-null.
-		 */
-		aclDatum = heap_getattr(oldtup,
-								Anum_pg_largeobject_metadata_lomacl,
-								RelationGetDescr(pg_lo_meta), &isnull);
-		if (!isnull)
-		{
-			newAcl = aclnewowner(DatumGetAclP(aclDatum),
-								 form_lo_meta->lomowner, newOwnerId);
-			values[Anum_pg_largeobject_metadata_lomacl - 1]
-				= PointerGetDatum(newAcl);
-			replaces[Anum_pg_largeobject_metadata_lomacl - 1] = true;
-		}
-
-		newtup = heap_modify_tuple(oldtup, RelationGetDescr(pg_lo_meta),
-								   values, nulls, replaces);
-
-		simple_heap_update(pg_lo_meta, &newtup->t_self, newtup);
-		CatalogUpdateIndexes(pg_lo_meta, newtup);
-
-		heap_freetuple(newtup);
-
-		/* Update owner dependency reference */
-		changeDependencyOnOwner(LargeObjectRelationId,
-								loid, newOwnerId);
-	}
-	systable_endscan(scan);
-
-	heap_close(pg_lo_meta, RowExclusiveLock);
-}
-
 /*
  * LargeObjectExists
  *

src/backend/catalog/pg_shdepend.c

@@ -32,6 +32,7 @@
 #include "catalog/pg_foreign_server.h"
 #include "catalog/pg_language.h"
 #include "catalog/pg_largeobject.h"
+#include "catalog/pg_largeobject_metadata.h"
 #include "catalog/pg_namespace.h"
 #include "catalog/pg_operator.h"
 #include "catalog/pg_opclass.h"
@@ -40,6 +41,7 @@
 #include "catalog/pg_shdepend.h"
 #include "catalog/pg_tablespace.h"
 #include "catalog/pg_type.h"
+#include "commands/alter.h"
 #include "commands/dbcommands.h"
 #include "commands/collationcmds.h"
 #include "commands/conversioncmds.h"
@@ -1335,22 +1337,10 @@ shdepReassignOwned(List *roleids, Oid newrole)
 			/* Issue the appropriate ALTER OWNER call */
 			switch (sdepForm->classid)
 			{
-				case CollationRelationId:
-					AlterCollationOwner_oid(sdepForm->objid, newrole);
-					break;
-
-				case ConversionRelationId:
-					AlterConversionOwner_oid(sdepForm->objid, newrole);
-					break;
-
 				case TypeRelationId:
 					AlterTypeOwnerInternal(sdepForm->objid, newrole, true);
 					break;
 
-				case OperatorRelationId:
-					AlterOperatorOwner_oid(sdepForm->objid, newrole);
-					break;
-
 				case NamespaceRelationId:
 					AlterSchemaOwner_oid(sdepForm->objid, newrole);
 					break;
@@ -1365,18 +1355,6 @@ shdepReassignOwned(List *roleids, Oid newrole)
 					ATExecChangeOwner(sdepForm->objid, newrole, true, AccessExclusiveLock);
 					break;
 
-				case ProcedureRelationId:
-					AlterFunctionOwner_oid(sdepForm->objid, newrole);
-					break;
-
-				case LanguageRelationId:
-					AlterLanguageOwner_oid(sdepForm->objid, newrole);
-					break;
-
-				case LargeObjectRelationId:
-					LargeObjectAlterOwner(sdepForm->objid, newrole);
-					break;
-
 				case DefaultAclRelationId:
 
 					/*
@@ -1385,14 +1363,6 @@ shdepReassignOwned(List *roleids, Oid newrole)
 					 */
 					break;
 
-				case OperatorClassRelationId:
-					AlterOpClassOwner_oid(sdepForm->objid, newrole);
-					break;
-
-				case OperatorFamilyRelationId:
-					AlterOpFamilyOwner_oid(sdepForm->objid, newrole);
-					break;
-
 				case ForeignServerRelationId:
 					AlterForeignServerOwner_oid(sdepForm->objid, newrole);
 					break;
@@ -1401,14 +1371,36 @@ shdepReassignOwned(List *roleids, Oid newrole)
 					AlterForeignDataWrapperOwner_oid(sdepForm->objid, newrole);
 					break;
 
-				case ExtensionRelationId:
-					AlterExtensionOwner_oid(sdepForm->objid, newrole);
-					break;
-
 				case EventTriggerRelationId:
 					AlterEventTriggerOwner_oid(sdepForm->objid, newrole);
 					break;
 
+				/* Generic alter owner cases */
+				case CollationRelationId:
+				case ConversionRelationId:
+				case OperatorRelationId:
+				case ProcedureRelationId:
+				case LanguageRelationId:
+				case LargeObjectRelationId:
+				case OperatorFamilyRelationId:
+				case OperatorClassRelationId:
+				case ExtensionRelationId:
+					{
+						Oid			classId = sdepForm->classid;
+						Relation	catalog;
+
+						if (classId == LargeObjectRelationId)
+							classId = LargeObjectMetadataRelationId;
+
+						catalog = heap_open(classId, RowExclusiveLock);
+
+						AlterObjectOwner_internal(catalog, sdepForm->objid,
+												  newrole);
+
+						heap_close(catalog, NoLock);
+					}
+					break;
+
 				default:
 					elog(ERROR, "unexpected classid %u", sdepForm->classid);
 					break;

src/backend/commands/aggregatecmds.c

@@ -267,18 +267,3 @@ RenameAggregate(List *name, List *args, const char *newname)
 	heap_close(rel, NoLock);
 	heap_freetuple(tup);
 }
-
-/*
- * Change aggregate owner
- */
-void
-AlterAggregateOwner(List *name, List *args, Oid newOwnerId)
-{
-	Oid			procOid;
-
-	/* Look up function and make sure it's an aggregate */
-	procOid = LookupAggNameTypeNames(name, args, false);
-
-	/* The rest is just like a function */
-	AlterFunctionOwner_oid(procOid, newOwnerId);
-}