refs: add a `optimize_required` field to `struct ref_storage_be`

To allow users of the refs namespace to check if the reference backend
requires optimization, add a new field `optimize_required` field to
`struct ref_storage_be`. This field is of type `optimize_required_fn`
which is also introduced in this commit.

Modify the debug, files, packed and reftable backend to implement this
field. A following commit will expose this via 'git pack-refs' and 'git
refs optimize'.

Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Acked-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/refs.c b/refs.c
index 0d0831f29b..5583f6e09d 100644
--- a/refs.c
+++ b/refs.c
@@ -2318,6 +2318,13 @@ int refs_optimize(struct ref_store *refs, struct refs_optimize_opts *opts)
 	return refs->be->optimize(refs, opts);
 }
 
+int refs_optimize_required(struct ref_store *refs,
+			   struct refs_optimize_opts *opts,
+			   bool *required)
+{
+	return refs->be->optimize_required(refs, opts, required);
+}
+
 int reference_get_peeled_oid(struct repository *repo,
 			     const struct reference *ref,
 			     struct object_id *peeled_oid)