+ return offset;
+}
+
+static int message_attribute_has_type(sd_rtnl_message *m, uint16_t attribute_type, uint16_t data_type) {
+ const NLType *type;
+ int r;
+
+ r = type_system_get_type(m->container_type_system[m->n_containers], &type, attribute_type);
+ if (r < 0)
+ return r;
+
+ if (type->type != data_type)
+ return -EINVAL;
+
+ return type->size;
+}
+
+int sd_rtnl_message_append_string(sd_rtnl_message *m, unsigned short type, const char *data) {
+ size_t length, size;
+ int r;
+
+ assert_return(m, -EINVAL);
+ assert_return(!m->sealed, -EPERM);
+ assert_return(data, -EINVAL);
+
+ r = message_attribute_has_type(m, type, NLA_STRING);
+ if (r < 0)
+ return r;
+ else
+ size = (size_t)r;
+
+ if (size) {
+ length = strnlen(data, size+1);
+ if (length > size)
+ return -EINVAL;
+ } else
+ length = strlen(data);
+
+ r = add_rtattr(m, type, data, length + 1);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+int sd_rtnl_message_append_u8(sd_rtnl_message *m, unsigned short type, uint8_t data) {
+ int r;
+
+ assert_return(m, -EINVAL);
+ assert_return(!m->sealed, -EPERM);
+
+ r = message_attribute_has_type(m, type, NLA_U8);
+ if (r < 0)
+ return r;
+
+ r = add_rtattr(m, type, &data, sizeof(uint8_t));
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+
+int sd_rtnl_message_append_u16(sd_rtnl_message *m, unsigned short type, uint16_t data) {
+ int r;
+
+ assert_return(m, -EINVAL);
+ assert_return(!m->sealed, -EPERM);
+
+ r = message_attribute_has_type(m, type, NLA_U16);
+ if (r < 0)
+ return r;
+
+ r = add_rtattr(m, type, &data, sizeof(uint16_t));
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+int sd_rtnl_message_append_u32(sd_rtnl_message *m, unsigned short type, uint32_t data) {
+ int r;
+
+ assert_return(m, -EINVAL);
+ assert_return(!m->sealed, -EPERM);
+
+ r = message_attribute_has_type(m, type, NLA_U32);
+ if (r < 0)
+ return r;
+
+ r = add_rtattr(m, type, &data, sizeof(uint32_t));
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+int sd_rtnl_message_append_in_addr(sd_rtnl_message *m, unsigned short type, const struct in_addr *data) {
+ int r;
+
+ assert_return(m, -EINVAL);
+ assert_return(!m->sealed, -EPERM);
+ assert_return(data, -EINVAL);
+
+ r = message_attribute_has_type(m, type, NLA_IN_ADDR);
+ if (r < 0)
+ return r;
+
+ r = add_rtattr(m, type, data, sizeof(struct in_addr));
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+int sd_rtnl_message_append_in6_addr(sd_rtnl_message *m, unsigned short type, const struct in6_addr *data) {
+ int r;
+
+ assert_return(m, -EINVAL);
+ assert_return(!m->sealed, -EPERM);
+ assert_return(data, -EINVAL);
+
+ r = message_attribute_has_type(m, type, NLA_IN_ADDR);
+ if (r < 0)
+ return r;
+
+ r = add_rtattr(m, type, data, sizeof(struct in6_addr));
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+int sd_rtnl_message_append_ether_addr(sd_rtnl_message *m, unsigned short type, const struct ether_addr *data) {
+ int r;
+
+ assert_return(m, -EINVAL);
+ assert_return(!m->sealed, -EPERM);
+ assert_return(data, -EINVAL);
+
+ r = message_attribute_has_type(m, type, NLA_ETHER_ADDR);
+ if (r < 0)
+ return r;
+
+ r = add_rtattr(m, type, data, ETH_ALEN);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+int sd_rtnl_message_append_cache_info(sd_rtnl_message *m, unsigned short type, const struct ifa_cacheinfo *info) {
+ int r;
+
+ assert_return(m, -EINVAL);
+ assert_return(!m->sealed, -EPERM);
+ assert_return(info, -EINVAL);
+
+ r = message_attribute_has_type(m, type, NLA_CACHE_INFO);
+ if (r < 0)
+ return r;
+
+ r = add_rtattr(m, type, info, sizeof(struct ifa_cacheinfo));
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+int sd_rtnl_message_open_container(sd_rtnl_message *m, unsigned short type) {
+ size_t size;
+ int r;
+
+ assert_return(m, -EINVAL);
+ assert_return(!m->sealed, -EPERM);
+ assert_return(m->n_containers < RTNL_CONTAINER_DEPTH, -ERANGE);
+
+ r = message_attribute_has_type(m, type, NLA_NESTED);
+ if (r < 0) {
+ const NLTypeSystemUnion *type_system_union;
+ int family;
+
+ r = message_attribute_has_type(m, type, NLA_UNION);
+ if (r < 0)
+ return r;
+ size = (size_t) r;
+
+ r = sd_rtnl_message_get_family(m, &family);
+ if (r < 0)
+ return r;
+
+ r = type_system_get_type_system_union(m->container_type_system[m->n_containers], &type_system_union, type);
+ if (r < 0)
+ return r;
+
+ r = type_system_union_protocol_get_type_system(type_system_union,
+ &m->container_type_system[m->n_containers + 1],
+ family);
+ if (r < 0)
+ return r;
+ } else {
+ size = (size_t)r;
+
+ r = type_system_get_type_system(m->container_type_system[m->n_containers],
+ &m->container_type_system[m->n_containers + 1],
+ type);
+ if (r < 0)
+ return r;
+ }
+
+ r = add_rtattr(m, type | NLA_F_NESTED, NULL, size);
+ if (r < 0)
+ return r;
+
+ m->container_offsets[m->n_containers ++] = r;
+
+ return 0;
+}
+
+int sd_rtnl_message_open_container_union(sd_rtnl_message *m, unsigned short type, const char *key) {
+ const NLTypeSystemUnion *type_system_union;
+ int r;
+
+ assert_return(m, -EINVAL);
+ assert_return(!m->sealed, -EPERM);
+
+ r = type_system_get_type_system_union(m->container_type_system[m->n_containers], &type_system_union, type);
+ if (r < 0)
+ return r;
+
+ r = type_system_union_get_type_system(type_system_union,
+ &m->container_type_system[m->n_containers + 1],
+ key);
+ if (r < 0)
+ return r;
+
+ r = sd_rtnl_message_append_string(m, type_system_union->match, key);
+ if (r < 0)
+ return r;
+
+ /* do we evere need non-null size */
+ r = add_rtattr(m, type, NULL, 0);
+ if (r < 0)
+ return r;
+
+ m->container_offsets[m->n_containers ++] = r;
+
+ return 0;
+}
+
+
+int sd_rtnl_message_close_container(sd_rtnl_message *m) {
+ assert_return(m, -EINVAL);
+ assert_return(!m->sealed, -EPERM);
+ assert_return(m->n_containers > 0, -EINVAL);
+
+ m->container_type_system[m->n_containers] = NULL;
+ m->n_containers --;
+