Function add_object_entry_from_pack

builtin/pack-objects.c:3787–3832

static int stdin_packs_hints_nr;

static int add_object_entry_from_pack(const struct object_id *oid,
				      struct packed_git *p,
				      uint32_t pos,
				      void *_data)
{
	off_t ofs;
	struct object_info oi = OBJECT_INFO_INIT;
	enum object_type type = OBJ_NONE;

	display_progress(progress_state, ++nr_seen);

	if (have_duplicate_entry(oid, 0))
		return 0;

	stdin_packs_found_nr++;

	ofs = nth_packed_object_offset(p, pos);

	oi.typep = &type;
	if (packed_object_info(p, ofs, &oi) < 0) {
		die(_("could not get type of object %s in pack %s"),
		    oid_to_hex(oid), p->pack_name);
	} else if (type == OBJ_COMMIT) {
		struct rev_info *revs = _data;
		/*
		 * commits in included packs are used as starting points
		 * for the subsequent revision walk
		 *
		 * Note that we do want to walk through commits that are
		 * present in excluded-open ('!') packs to pick up any
		 * objects reachable from them not present in the
		 * excluded-closed ('^') packs.
		 *
		 * However, we'll only add those objects to the packing
		 * list after checking `want_object_in_pack()` below.
		 */
		add_pending_oid(revs, NULL, oid, 0);
	}

	if (!want_object_in_pack(oid, 0, &p, &ofs))
		return 0;

	create_object_entry(oid, type, 0, 0, 0, p, ofs);

	return 0;
}

static void show_object_pack_hint(struct object *object, const char *name,
				  void *data)