sd-netlink: introduce sd_netlink_message_append_container_data()

src/libsystemd/libsystemd.sym

@@ -818,6 +818,7 @@ global:
         sd_netlink_message_append_s32;
         sd_netlink_message_append_s64;
         sd_netlink_message_append_data;
+        sd_netlink_message_append_container_data;
         sd_netlink_message_append_in_addr;
         sd_netlink_message_append_in6_addr;
         sd_netlink_message_append_sockaddr_in;

src/libsystemd/sd-netlink/netlink-message-nfnl.c

@@ -290,20 +290,6 @@ int sd_nfnl_nft_message_del_setelems_begin(
         return r;
 }
 
-static int add_data(sd_netlink_message *m, uint16_t attr, const void *data, uint32_t dlen) {
-        int r;
-
-        r = sd_netlink_message_open_container(m, attr);
-        if (r < 0)
-                return r;
-
-        r = sd_netlink_message_append_data(m, NFTA_DATA_VALUE, data, dlen);
-        if (r < 0)
-                return r;
-
-        return sd_netlink_message_close_container(m); /* attr */
-}
-
 int sd_nfnl_nft_message_add_setelem(
                 sd_netlink_message *m,
                 uint32_t index,
@@ -318,12 +304,12 @@ int sd_nfnl_nft_message_add_setelem(
         if (r < 0)
                 return r;
 
-        r = add_data(m, NFTA_SET_ELEM_KEY, key, key_len);
+        r = sd_netlink_message_append_container_data(m, NFTA_SET_ELEM_KEY, NFTA_DATA_VALUE, key, key_len);
         if (r < 0)
                 goto cancel;
 
         if (data) {
-                r = add_data(m, NFTA_SET_ELEM_DATA, data, data_len);
+                r = sd_netlink_message_append_container_data(m, NFTA_SET_ELEM_DATA, NFTA_DATA_VALUE, data, data_len);
                 if (r < 0)
                         goto cancel;
         }

src/libsystemd/sd-netlink/netlink-message.c

@@ -452,6 +452,29 @@ _public_ int sd_netlink_message_append_data(sd_netlink_message *m, unsigned shor
         return 0;
 }
 
+_public_ int sd_netlink_message_append_container_data(
+                sd_netlink_message *m,
+                unsigned short container_type,
+                unsigned short type,
+                const void *data,
+                size_t len) {
+
+        int r;
+
+        assert_return(m, -EINVAL);
+        assert_return(!m->sealed, -EPERM);
+
+        r = sd_netlink_message_open_container(m, container_type);
+        if (r < 0)
+                return r;
+
+        r = sd_netlink_message_append_data(m, type, data, len);
+        if (r < 0)
+                return r;
+
+        return sd_netlink_message_close_container(m);
+}
+
 int netlink_message_append_in_addr_union(sd_netlink_message *m, unsigned short type, int family, const union in_addr_union *data) {
         int r;