1 files changed, 69 insertions, 0 deletions
diff --git a/src/backend/commands/lockcmds.c b/src/backend/commands/lockcmds.c
new file mode 100644
index 00000000000..c91669572ef
--- /dev/null
+++ b/src/backend/commands/lockcmds.c
@@ -0,0 +1,69 @@
+/*-------------------------------------------------------------------------
+ *
+ * lockcmds.c
+ *	  Lock command support code
+ *
+ * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *	  $Header: /cvsroot/pgsql/src/backend/commands/lockcmds.c,v 1.1 2002/04/15 05:22:03 tgl Exp $
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include "access/heapam.h"
+#include "catalog/namespace.h"
+#include "commands/lockcmds.h"
+#include "miscadmin.h"
+#include "utils/acl.h"
+
+
+/*
+ * LOCK TABLE
+ */
+void
+LockTableCommand(LockStmt *lockstmt)
+{
+	List	   *p;
+
+	/*
+	 * Iterate over the list and open, lock, and close the relations one
+	 * at a time
+	 */
+
+	foreach(p, lockstmt->relations)
+	{
+		RangeVar   *relation = lfirst(p);
+		Oid			reloid;
+		int32		aclresult;
+		Relation	rel;
+
+		/*
+		 * We don't want to open the relation until we've checked privilege.
+		 * So, manually get the relation OID.
+		 */
+		reloid = RangeVarGetRelid(relation, false);
+
+		if (lockstmt->mode == AccessShareLock)
+			aclresult = pg_class_aclcheck(reloid, GetUserId(),
+										  ACL_SELECT);
+		else
+			aclresult = pg_class_aclcheck(reloid, GetUserId(),
+										  ACL_UPDATE | ACL_DELETE);
+
+		if (aclresult != ACLCHECK_OK)
+			elog(ERROR, "LOCK TABLE: permission denied");
+
+		rel = relation_open(reloid, lockstmt->mode);
+
+		/* Currently, we only allow plain tables to be locked */
+		if (rel->rd_rel->relkind != RELKIND_RELATION)
+			elog(ERROR, "LOCK TABLE: %s is not a table",
+				 relation->relname);
+
+		relation_close(rel, NoLock);	/* close rel, keep lock */
+	}
+}