Fix previous commit: shellcheck reported a warning

Reference:
https://xmpp.org/rfcs/rfc6121.html#roster-syntax-items-approved

Additionally, when roster contains unknown attribute, discard it and
show a warning

.github/container/ejabberdctl.template

@@ -79,6 +79,9 @@ fi
 if [ -n "$INET_DIST_INTERFACE" ] ; then
     INET_DIST_INTERFACE2=$("$ERL" $ERLANG_OPTS -noshell -eval 'case inet:parse_address("'$INET_DIST_INTERFACE'") of {ok,IP} -> io:format("~p",[IP]); _ -> ok end.' -s erlang halt)
     if [ -n "$INET_DIST_INTERFACE2" ] ; then
+        if [ "$(echo "$INET_DIST_INTERFACE2" | grep -o "," | wc -l)" -eq 7 ] ; then
+            INET_DIST_INTERFACE2="$INET_DIST_INTERFACE2 -proto_dist inet6_tcp"
+        fi
         ERLANG_OPTS="$ERLANG_OPTS -kernel inet_dist_use_interface $INET_DIST_INTERFACE2"
     fi
 fi

ejabberdctl.template

@@ -78,6 +78,9 @@ fi
 if [ -n "$INET_DIST_INTERFACE" ] ; then
     INET_DIST_INTERFACE2=$("$ERL" $ERLANG_OPTS -noshell -eval 'case inet:parse_address("'$INET_DIST_INTERFACE'") of {ok,IP} -> io:format("~p",[IP]); _ -> ok end.' -s erlang halt)
     if [ -n "$INET_DIST_INTERFACE2" ] ; then
+        if [ "$(echo "$INET_DIST_INTERFACE2" | grep -o "," | wc -l)" -eq 7 ] ; then
+            INET_DIST_INTERFACE2="$INET_DIST_INTERFACE2 -proto_dist inet6_tcp"
+        fi
         ERLANG_OPTS="$ERLANG_OPTS -kernel inet_dist_use_interface $INET_DIST_INTERFACE2"
     fi
 fi

src/ejabberd_sql_sup.erl

@@ -37,30 +37,36 @@ start(Host) ->
     case is_started(Host) of
 	true -> ok;
 	false ->
-	    App = case ejabberd_option:sql_type(Host) of
-		      mysql -> p1_mysql;
-		      pgsql -> p1_pgsql;
-		      sqlite -> sqlite3;
-		      _ -> odbc
-		  end,
-	    ejabberd:start_app(App),
-	    Spec = #{id => gen_mod:get_module_proc(Host, ?MODULE),
-		     start => {ejabberd_sql_sup, start_link, [Host]},
-		     restart => transient,
-		     shutdown => infinity,
-		     type => supervisor,
-		     modules => [?MODULE]},
-	    case supervisor:start_child(ejabberd_db_sup, Spec) of
-		{ok, _} ->
-                    ejabberd_sql_schema:start(Host),
-                    ok;
-		{error, {already_started, Pid}} ->
-                    %% Wait for the supervisor to fully start
-                    _ = supervisor:count_children(Pid),
-                    ok;
-		{error, Why} = Err ->
-		    ?ERROR_MSG("Failed to start ~ts: ~p", [?MODULE, Why]),
-		    Err
+	    case lists:member(Host, ejabberd_option:hosts()) of
+		false ->
+		    ?WARNING_MSG("Rejecting start of sql worker for unknown host: ~ts", [Host]),
+		    {error, invalid_host};
+		true ->
+		    App = case ejabberd_option:sql_type(Host) of
+			      mysql -> p1_mysql;
+			      pgsql -> p1_pgsql;
+			      sqlite -> sqlite3;
+			      _ -> odbc
+			  end,
+		    ejabberd:start_app(App),
+		    Spec = #{id => gen_mod:get_module_proc(Host, ?MODULE),
+			start => {ejabberd_sql_sup, start_link, [Host]},
+			restart => transient,
+			shutdown => infinity,
+			type => supervisor,
+			modules => [?MODULE]},
+		    case supervisor:start_child(ejabberd_db_sup, Spec) of
+			{ok, _} ->
+			    ejabberd_sql_schema:start(Host),
+			    ok;
+			{error, {already_started, Pid}} ->
+			    %% Wait for the supervisor to fully start
+			    _ = supervisor:count_children(Pid),
+			    ok;
+			{error, Why} = Err ->
+			    ?ERROR_MSG("Failed to start ~ts: ~p", [?MODULE, Why]),
+			    Err
+		    end
 	    end
     end.
 

src/prosody2ejabberd.erl

@@ -322,8 +322,13 @@ convert_roster_item(LUser, LServer, JIDstring, LuaList) ->
 			  [R#roster{name = Name}];
 		     ({<<"persist">>, false}, _) ->
 			  [];
-		     (_, []) ->
-			  []
+		     ({<<"approved">>, _}, [R]) ->
+			  [R];
+		     (A, [R]) ->
+	                  io:format("Warning: roster of user ~ts@~ts includes unknown "
+                                    "attribute:~n   ~p~nand that one is discarded.~n",
+                                    [LUser, LServer, A]),
+			  [R]
 		  end, [InitR], LuaList)
     catch _:{bad_jid, _} ->
 	    []