Merge pull request #5652 from taosdata/fix/TD-3642

[TD-3642]<fix>: fix staging directory resource leak

src/dnode/src/dnodeMain.c

@@ -238,9 +238,11 @@ static int32_t dnodeInitStorage() {
   }
 
   TDIR *tdir = tfsOpendir("vnode_bak/.staging");
-  if (tfsReaddir(tdir) != NULL) {
-    dError("vnode_bak/.staging dir not empty, fix it first.");
+  bool stagingNotEmpty = tfsReaddir(tdir) != NULL;
   tfsClosedir(tdir);
+
+  if (stagingNotEmpty) {
+    dError("vnode_bak/.staging dir not empty, fix it first.");
     return -1;
   }