From 3ff71a888619335878820bca28285fee56fccfde Mon Sep 17 00:00:00 2001
From: Patrick Steinhardt <ps@pks.im>
Date: Tue, 24 Mar 2020 19:43:43 +0100
Subject: wire up reftable

---
 include/git2/sys/refdb_backend.h |  4 ++++
 src/refdb.c                      | 35 ++++++++++++++++++++++++-----------
 src/refdb_reftable.c             |  2 --
 3 files changed, 28 insertions(+), 13 deletions(-)

diff --git a/include/git2/sys/refdb_backend.h b/include/git2/sys/refdb_backend.h
index 8e22c4f02..0bdd2242c 100644
--- a/include/git2/sys/refdb_backend.h
+++ b/include/git2/sys/refdb_backend.h
@@ -235,6 +235,10 @@ GIT_EXTERN(int) git_refdb_backend_fs(
 	git_refdb_backend **backend_out,
 	git_repository *repo);
 
+GIT_EXTERN(int) git_refdb_backend_reftable(
+	git_refdb_backend **out,
+	git_repository *repository);
+
 /**
  * Sets the custom backend to an existing reference DB
  *
diff --git a/src/refdb.c b/src/refdb.c
index fbbf5193c..82284b2de 100644
--- a/src/refdb.c
+++ b/src/refdb.c
@@ -35,27 +35,40 @@ int git_refdb_new(git_refdb **out, git_repository *repo)
 
 int git_refdb_open(git_refdb **out, git_repository *repo)
 {
+	git_buf refs = GIT_BUF_INIT;
+	git_refdb_backend *backend;
 	git_refdb *db;
-	git_refdb_backend *dir;
+	int error;
 
 	assert(out && repo);
 
 	*out = NULL;
 
-	if (git_refdb_new(&db, repo) < 0)
-		return -1;
-
-	/* Add the default (filesystem) backend */
-	if (git_refdb_backend_fs(&dir, repo) < 0) {
-		git_refdb_free(db);
-		return -1;
+	if ((error = git_refdb_new(&db, repo)) < 0)
+		goto out;
+
+	if ((error = git_buf_joinpath(&refs, git_repository_path(repo), "refs")) < 0)
+		goto out;
+
+	/*
+	 * Use filesystem-based backend in case ".git/refs" is a directory,
+	 * otherwise use the reftable backend.
+	 */
+	if (git_path_isfile(refs.ptr)) {
+		if ((error = git_refdb_backend_reftable(&backend, repo)) < 0)
+			goto out;
+	} else {
+		if ((error = git_refdb_backend_fs(&backend, repo)) < 0)
+			goto out;
 	}
 
 	db->repo = repo;
-	db->backend = dir;
-
+	db->backend = backend;
 	*out = db;
-	return 0;
+out:
+	if (error)
+		git_refdb_free(db);
+	return error;
 }
 
 static void refdb_free_backend(git_refdb *db)
diff --git a/src/refdb_reftable.c b/src/refdb_reftable.c
index 601f3bb9e..74d0462b4 100644
--- a/src/refdb_reftable.c
+++ b/src/refdb_reftable.c
@@ -5,8 +5,6 @@
  * a Linking Exception. For full terms see the included COPYING file.
  */
 
-#include "refdb_fs.h"
-
 #include "git2/sys/refdb_backend.h"
 #include "git2/sys/refs.h"
 #include "wildmatch.h"
-- 
cgit v1.2.1