odb: add transaction interface

Transactions are managed via the {begin,end}_odb_transaction() function
in the object-file subsystem and its implementation is specific to the
files object source. Introduce odb_transaction_{begin,commit}() in the
odb subsystem to provide an eventual object source agnostic means to
manage transactions.

Update call sites to instead manage transactions through the odb
subsystem. Also rename {begin,end}_odb_transaction() functions to
object_file_transaction_{begin,commit}() to clarify the object source it
supports.

Signed-off-by: Justin Tobler <jltobler@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/odb.c b/odb.c
index 2a92a018c4..af9534bfe1 100644
--- a/odb.c
+++ b/odb.c
@@ -1051,3 +1051,13 @@ void odb_clear(struct object_database *o)
 	hashmap_clear(&o->pack_map);
 	string_list_clear(&o->submodule_source_paths, 0);
 }
+
+struct odb_transaction *odb_transaction_begin(struct object_database *odb)
+{
+	return object_file_transaction_begin(odb->sources);
+}
+
+void odb_transaction_commit(struct odb_transaction *transaction)
+{
+	object_file_transaction_commit(transaction);
+}