[PATCH v4 08/21] refs: add methods to init refs db

@@ -178,13 +178,7 @@ static int create_default_files(const char *template_path)
 	char junk[2];
 	int reinit;
 	int filemode;
-
-	/*
-	 * Create .git/refs/{heads,tags}
-	 */
-	safe_create_dir(git_path_buf(&buf, "refs"), 1);
-	safe_create_dir(git_path_buf(&buf, "refs/heads"), 1);
-	safe_create_dir(git_path_buf(&buf, "refs/tags"), 1);
+	struct strbuf err = STRBUF_INIT;
 
 	/* Just look for `init.templatedir` */
 	git_config(git_init_db_config, NULL);

@@ -208,12 +202,18 @@ static int create_default_files(const char *template_path)
 	 */
 	if (shared_repository) {
 		adjust_shared_perm(get_git_dir());
-		adjust_shared_perm(git_path_buf(&buf, "refs"));
-		adjust_shared_perm(git_path_buf(&buf, "refs/heads"));
-		adjust_shared_perm(git_path_buf(&buf, "refs/tags"));
 	}
 
 	/*
+	 * We need to create a "refs" dir in any case so that older
+	 * versions of git can tell that this is a repository.
+	 */
+	safe_create_dir(git_path("refs"), 1);
+	
+	if (refs_init_db(&err, shared_repository))
+		die("failed to set up refs db: %s", err.buf);
+
+	/*
 	 * Create the default symlink from ".git/HEAD" to the "master"
 	 * branch, if it does not exist yet.
 	 */

@@ -1117,6 +1117,11 @@ int rename_ref_available(const char *oldname, const char *newname)
 }
 
 /* backend functions */
+int refs_init_db(struct strbuf *err, int shared)
+{
+	return the_refs_backend->init_db(err, shared);
+}
+
 int ref_transaction_commit(struct ref_transaction *transaction,
 			   struct strbuf *err)
 {

@@ -66,6 +66,8 @@ extern int ref_exists(const char *refname);
 
 extern int is_branch(const char *refname);
 
+extern int refs_init_db(struct strbuf *err, int shared);
+
 /*
  * If refname is a non-symbolic reference that refers to a tag object,
  * and the tag can be (recursively) dereferenced to a non-tag object,

@@ -3558,9 +3558,25 @@ static int files_reflog_expire(const char *refname, const unsigned char *sha1,
 	return -1;
 }
 
+static int files_init_db(struct strbuf *err, int shared)
+{
+	/*
+	 * Create .git/refs/{heads,tags}
+	 */
+	safe_create_dir(git_path("refs/heads"), 1);
+	safe_create_dir(git_path("refs/tags"), 1);
+	if (shared) {
+		adjust_shared_perm(git_path("refs"));
+		adjust_shared_perm(git_path("refs/heads"));
+		adjust_shared_perm(git_path("refs/tags"));
+	}
+	return 0;
+}
+
 struct ref_storage_be refs_be_files = {
 	NULL,
 	"files",
+	files_init_db,
 	files_transaction_commit,
 	files_initial_transaction_commit,
 

@@ -208,6 +208,7 @@ const char *find_descendant_ref(const char *dirname,
 int rename_ref_available(const char *oldname, const char *newname);
 
 /* refs backends */
+typedef int ref_init_db_fn(struct strbuf *err, int shared);
 typedef int ref_transaction_commit_fn(struct ref_transaction *transaction,
 				      struct strbuf *err);
 

@@ -267,6 +268,7 @@ typedef int for_each_replace_ref_fn(each_ref_fn fn, void *cb_data);
 struct ref_storage_be {
 	struct ref_storage_be *next;
 	const char *name;
+	ref_init_db_fn *init_db;
 	ref_transaction_commit_fn *transaction_commit;
 	ref_transaction_commit_fn *initial_transaction_commit;