refs: pass NULL to refs_read_ref_full() because object ID is not needed

refs_read_ref_full() wraps refs_resolve_ref_unsafe(), which handles a
NULL oid pointer of callers not interested in the resolved object ID.
Pass NULL from files_copy_or_rename_ref() to clarify that it is one
such caller.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/refs/files-backend.c b/refs/files-backend.c
index d60767ab739f0e20e45c700368f7f9f24a52c3f8..0ea66a28b6c9b951041c050c5489c8110905549c 100644 (file)
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -1327,7 +1327,7 @@ static int files_copy_or_rename_ref(struct ref_store *ref_store,
 {
        struct files_ref_store *refs =
                files_downcast(ref_store, REF_STORE_WRITE, "rename_ref");
-       struct object_id oid, orig_oid;
+       struct object_id orig_oid;
        int flag = 0, logmoved = 0;
        struct ref_lock *lock;
        struct stat loginfo;
@@ -1395,7 +1395,7 @@ static int files_copy_or_rename_ref(struct ref_store *ref_store,
         */
        if (!copy && !refs_read_ref_full(&refs->base, newrefname,
                                RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE,
-                               &oid, NULL) &&
+                               NULL, NULL) &&
            refs_delete_ref(&refs->base, NULL, newrefname,
                            NULL, REF_NO_DEREF)) {
                if (errno == EISDIR) {