lua: Ensure LuaGetState will always be called with a valid extension

Otherwise the returned state wouldn't be stored in the extension, and
would eventually be leaked

modules/lua/extension.c

@@ -540,6 +540,8 @@ static int Control( extensions_manager_t *p_mgr, int i_control, va_list args )
             p_ext = ( extension_t* ) va_arg( args, extension_t* );
             pppsz = ( char*** ) va_arg( args, char*** );
             ppus = ( uint16_t** ) va_arg( args, uint16_t** );
+            if( p_ext == NULL )
+                return VLC_EGENERIC;
             return GetMenuEntries( p_mgr, p_ext, pppsz, ppus );
 
         case EXTENSION_TRIGGER_ONLY:
@@ -794,9 +796,8 @@ exit:
 static lua_State* GetLuaState( extensions_manager_t *p_mgr,
                                extension_t *p_ext )
 {
-    lua_State *L = NULL;
-    if( p_ext )
-        L = p_ext->p_sys->L;
+    assert( p_ext != NULL );
+    lua_State *L = p_ext->p_sys->L;
 
     if( !L )
     {
@@ -815,69 +816,66 @@ static lua_State* GetLuaState( extensions_manager_t *p_mgr,
         luaL_register_namespace( L, "vlc", p_reg );
         luaopen_msg( L );
 
-        if( p_ext )
+        /* Load more libraries */
+        luaopen_config( L );
+        luaopen_dialog( L, p_ext );
+        luaopen_input( L );
+        luaopen_msg( L );
+        if( vlclua_fd_init( L, &p_ext->p_sys->dtable ) )
         {
-            /* Load more libraries */
-            luaopen_config( L );
-            luaopen_dialog( L, p_ext );
-            luaopen_input( L );
-            luaopen_msg( L );
-            if( vlclua_fd_init( L, &p_ext->p_sys->dtable ) )
-            {
-                lua_close( L );
-                return NULL;
-            }
-            luaopen_object( L );
-            luaopen_osd( L );
-            luaopen_playlist( L );
-            luaopen_sd_intf( L );
-            luaopen_stream( L );
-            luaopen_strings( L );
-            luaopen_variables( L );
-            luaopen_video( L );
-            luaopen_vlm( L );
-            luaopen_volume( L );
-            luaopen_xml( L );
+            lua_close( L );
+            return NULL;
+        }
+        luaopen_object( L );
+        luaopen_osd( L );
+        luaopen_playlist( L );
+        luaopen_sd_intf( L );
+        luaopen_stream( L );
+        luaopen_strings( L );
+        luaopen_variables( L );
+        luaopen_video( L );
+        luaopen_vlm( L );
+        luaopen_volume( L );
+        luaopen_xml( L );
 #if defined(_WIN32) && !VLC_WINSTORE_APP
-            luaopen_win( L );
+        luaopen_win( L );
 #endif
 
-            /* Register extension specific functions */
-            lua_getglobal( L, "vlc" );
-            lua_pushcfunction( L, vlclua_extension_deactivate );
-            lua_setfield( L, -2, "deactivate" );
-            lua_pushcfunction( L, vlclua_extension_keep_alive );
-            lua_setfield( L, -2, "keep_alive" );
+        /* Register extension specific functions */
+        lua_getglobal( L, "vlc" );
+        lua_pushcfunction( L, vlclua_extension_deactivate );
+        lua_setfield( L, -2, "deactivate" );
+        lua_pushcfunction( L, vlclua_extension_keep_alive );
+        lua_setfield( L, -2, "keep_alive" );
 
-            /* Setup the module search path */
-            if( !strncmp( p_ext->psz_name, "zip://", 6 ) )
-            {
-                /* Load all required modules manually */
-                lua_register( L, "require", &vlclua_extension_require );
-            }
-            else
-            {
-                if( vlclua_add_modules_path( L, p_ext->psz_name ) )
-                {
-                    msg_Warn( p_mgr, "Error while setting the module "
-                              "search path for %s", p_ext->psz_name );
-                    vlclua_fd_cleanup( &p_ext->p_sys->dtable );
-                    lua_close( L );
-                    return NULL;
-                }
-            }
-            /* Load and run the script(s) */
-            if( vlclua_dofile( VLC_OBJECT( p_mgr ), L, p_ext->psz_name ) )
+        /* Setup the module search path */
+        if( !strncmp( p_ext->psz_name, "zip://", 6 ) )
+        {
+            /* Load all required modules manually */
+            lua_register( L, "require", &vlclua_extension_require );
+        }
+        else
+        {
+            if( vlclua_add_modules_path( L, p_ext->psz_name ) )
             {
-                msg_Warn( p_mgr, "Error loading script %s: %s", p_ext->psz_name,
-                          lua_tostring( L, lua_gettop( L ) ) );
+                msg_Warn( p_mgr, "Error while setting the module "
+                          "search path for %s", p_ext->psz_name );
                 vlclua_fd_cleanup( &p_ext->p_sys->dtable );
                 lua_close( L );
                 return NULL;
             }
-
-            p_ext->p_sys->L = L;
         }
+        /* Load and run the script(s) */
+        if( vlclua_dofile( VLC_OBJECT( p_mgr ), L, p_ext->psz_name ) )
+        {
+            msg_Warn( p_mgr, "Error loading script %s: %s", p_ext->psz_name,
+                      lua_tostring( L, lua_gettop( L ) ) );
+            vlclua_fd_cleanup( &p_ext->p_sys->dtable );
+            lua_close( L );
+            return NULL;
+        }
+
+        p_ext->p_sys->L = L;
     }
 
     return L;