refs: add method for initial ref transaction commit

Signed-off-by: Ronnie Sahlberg <rsahlberg@google.com>
Signed-off-by: David Turner <dturner@twopensource.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

refs.c

@@ -1524,3 +1524,11 @@ int reflog_expire(const char *refname, const unsigned char *sha1,
 				       prepare_fn, should_prune_fn,
 				       cleanup_fn, policy_cb_data);
 }
+
+int initial_ref_transaction_commit(struct ref_transaction *transaction,
+				   struct strbuf *err)
+{
+	struct ref_store *refs = get_ref_store(NULL);
+
+	return refs->be->initial_transaction_commit(refs, transaction, err);
+}

refs/files-backend.c

@@ -3829,11 +3829,12 @@ static int ref_present(const char *refname,
 	return string_list_has_string(affected_refnames, refname);
 }
 
-int initial_ref_transaction_commit(struct ref_transaction *transaction,
-				   struct strbuf *err)
+static int files_initial_transaction_commit(struct ref_store *ref_store,
+					    struct ref_transaction *transaction,
+					    struct strbuf *err)
 {
 	struct files_ref_store *refs =
-		get_files_ref_store(NULL, "initial_ref_transaction_commit");
+		files_downcast(ref_store, 0, "initial_ref_transaction_commit");
 	int ret = 0, i;
 	struct string_list affected_refnames = STRING_LIST_INIT_NODUP;
 
@@ -4061,6 +4062,7 @@ struct ref_storage_be refs_be_files = {
 	"files",
 	files_ref_store_create,
 	files_transaction_commit,
+	files_initial_transaction_commit,
 
 	files_pack_refs,
 	files_peel_ref,

refs/refs-internal.h

@@ -582,6 +582,7 @@ struct ref_storage_be {
 	const char *name;
 	ref_store_init_fn *init;
 	ref_transaction_commit_fn *transaction_commit;
+	ref_transaction_commit_fn *initial_transaction_commit;
 
 	pack_refs_fn *pack_refs;
 	peel_ref_fn *peel_ref;