Don't validate an option in gen_mod:get*opt() functions

The changes are very similar to those from previous commit:
* Now there is no need to pass validating function in
  gen_mod:get_opt() and gen_mod:get_module_opt() functions,
  because the modules' configuration keeps already validated values.
* New functions gen_mod:get_opt/2 and gen_mod:get_module_opt/3 are
  introduced.
* Functions gen_mod:get_opt/4 and get_module_opt/5 are deprecated.
  If the functions are still called, the "function" argument is
  simply ignored.
* Validating callback Mod:listen_opt_type/1 is introduced to validate
  listening options at startup.

1 files changed, 45 insertions, 18 deletions

diff --git a/src/ejabberd_listener.erl b/src/ejabberd_listener.erl
index 64e7f83b0..653ad931a 100644
--- a/src/ejabberd_listener.erl
+++ b/src/ejabberd_listener.erl
@@ -52,7 +52,6 @@ listeners_childspec() ->
     Ls = ejabberd_config:get_option(listen, []),
     Specs = lists:map(
 	      fun({Port, Module, Opts}) ->
-		      maybe_start_sip(Module),
 		      ets:insert(?MODULE, {Port, Module, Opts}),
 		      {Port,
 		       {?MODULE, start, [Port, Module, Opts]},
@@ -82,10 +81,11 @@ report_duplicated_portips(L) ->
   end.
 
 start(Port, Module, Opts) ->
+    NewOpts = validate_module_options(Module, Opts),
     %% Check if the module is an ejabberd listener or an independent listener
     case Module:socket_type() of
-	independent -> Module:start_listener(Port, Opts);
-	_ -> start_dependent(Port, Module, Opts)
+	independent -> Module:start_listener(Port, NewOpts);
+	_ -> start_dependent(Port, Module, NewOpts)
     end.
 
 %% @spec(Port, Module, Opts) -> {ok, Pid} | {error, ErrorMessage}
@@ -356,7 +356,6 @@ start_listener2(Port, Module, Opts) ->
     %% It is only required to start the supervisor in some cases.
     %% But it doesn't hurt to attempt to start it for any listener.
     %% So, it's normal (and harmless) that in most cases this call returns: {error, {already_started, pid()}}
-    maybe_start_sip(Module),
     start_listener_sup(Port, Module, Opts).
 
 start_module_sup(_Port, Module) ->
@@ -427,12 +426,6 @@ delete_listener(PortIP, Module, Opts) ->
     PortIP1 = {Port, IPT, Proto},
     stop_listener(PortIP1, Module).
 
-
-maybe_start_sip(esip_socket) ->
-    ejabberd:start_app(esip);
-maybe_start_sip(_) ->
-    ok.
-
 config_reloaded() ->
     New = ejabberd_config:get_option(listen, []),
     Old = ets:tab2list(?MODULE),
@@ -626,6 +619,47 @@ transform_options({listen, LOpts}, Opts) ->
 transform_options(Opt, Opts) ->
     [Opt|Opts].
 
+-spec validate_module_options(module(), [{atom(), any()}]) -> [{atom(), any()}].
+validate_module_options(Module, Opts) ->
+    try Module:listen_opt_type('') of
+	_ ->
+	    lists:filtermap(
+	      fun({Opt, Val}) ->
+		      case validate_module_option(Module, Opt, Val) of
+			  {ok, NewVal} -> {true, {Opt, NewVal}};
+			  error -> false
+		      end
+	      end, Opts)
+    catch _:undef ->
+	    ?WARNING_MSG("module '~s' doesn't export listen_opt_type/1",
+			 [Module]),
+	    Opts
+    end.
+
+-spec validate_module_option(module(), atom(), any()) -> {ok, any()} | error.
+validate_module_option(Module, Opt, Val) ->
+    case Module:listen_opt_type(Opt) of
+	VFun when is_function(VFun) ->
+	    try VFun(Val) of
+		NewVal -> {ok, NewVal}
+	    catch {invalid_syntax, Error} ->
+		    ?ERROR_MSG("ignoring listen option '~s' with "
+			       "invalid value: ~p: ~s",
+			       [Opt, Val, Error]),
+		    error;
+		  _:_ ->
+		    ?ERROR_MSG("ignoring listen option '~s' with "
+			       "invalid value: ~p",
+			       [Opt, Val]),
+		    error
+	    end;
+	KnownOpts when is_list(KnownOpts) ->
+	    ?ERROR_MSG("unknown listen option '~s' for '~s' will be likely "
+		       "ignored, available options are: ~s",
+		       [Opt, Module, misc:join_atoms(KnownOpts, <<", ">>)]),
+	    {ok, Val}
+    end.
+
 -type transport() :: udp | tcp.
 -type port_ip_transport() :: inet:port_number() |
                              {inet:port_number(), transport()} |
@@ -647,7 +681,7 @@ validate_cfg(L) ->
                         true = ?IS_TRANSPORT(T),
                         {{Port, IP, T}, Mod, Opts};
                    ({module, Mod}, {Port, _, Opts}) ->
-                        {Port, prepare_mod(Mod), Opts};
+                        {Port, Mod, Opts};
                    (Opt, {Port, Mod, Opts}) ->
                         {Port, Mod, [Opt|Opts]}
                 end, {{5222, all_zero_ip(LOpts), tcp}, ejabberd_c2s, []}, LOpts)
@@ -666,13 +700,6 @@ prepare_ip(IP) when is_list(IP) ->
 prepare_ip(IP) when is_binary(IP) ->
     prepare_ip(binary_to_list(IP)).
 
-prepare_mod(ejabberd_sip) ->
-    prepare_mod(sip);
-prepare_mod(sip) ->
-    esip_socket;
-prepare_mod(Mod) when is_atom(Mod) ->
-    Mod.
-
 all_zero_ip(Opts) ->
     case proplists:get_bool(inet6, Opts) of
 	true -> {0,0,0,0,0,0,0,0};