index_file_path = g_build_filename(directory, "index",
index_basename->str, NULL);
mapped_file = g_mapped_file_new(index_file_path, FALSE, NULL);
index_file_path = g_build_filename(directory, "index",
index_basename->str, NULL);
mapped_file = g_mapped_file_new(index_file_path, FALSE, NULL);