+static void add_refs_to_oidset(struct oidset *oids, struct ref *refs)
+{
+ for (; refs; refs = refs->next)
+ oidset_insert(oids, &refs->old_oid);
+}
+
+static int tip_oids_contain(struct oidset *tip_oids,
+ struct ref *unmatched, struct ref *newlist,
+ const struct object_id *id)
+{
+ /*
+ * Note that this only looks at the ref lists the first time it's
+ * called. This works out in filter_refs() because even though it may
+ * add to "newlist" between calls, the additions will always be for
+ * oids that are already in the set.
+ */
+ if (!tip_oids->map.tablesize) {
+ add_refs_to_oidset(tip_oids, unmatched);
+ add_refs_to_oidset(tip_oids, newlist);
+ }
+ return oidset_contains(tip_oids, id);
+}
+