Add multiple results and timeout handling to the Mac OS mDNS native extension

src/pkg/mdns/mdns_extension.cc

 // Copyright (c) 2015, the Fletch project authors. Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE.md file.
 
 #include <assert.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
 #include "include/dart_api.h"
@@ skipping 15 matching lines @@
         request_type->type == Dart_CObject_kInt32) {
       switch (request_type->value.as_int32) {
         case kEchoRequest:
           if (message->value.as_array.length == 3) {
             Dart_CObject* argument = message->value.as_array.values[2];
             HandleEcho(reply_port->value.as_send_port.id, argument);
             return;
           }
 
         case kLookupRequest:
-          if (message->value.as_array.length == 4) {
+          if (message->value.as_array.length == 5) {
             Dart_CObject* type = message->value.as_array.values[2];
             Dart_CObject* name = message->value.as_array.values[3];
+            Dart_CObject* timeout = message->value.as_array.values[4];
             if (type->type == Dart_CObject_kInt32 &&
-                name->type == Dart_CObject_kString) {
+                name->type == Dart_CObject_kString &&
+                timeout->type == Dart_CObject_kInt32) {
               HandleLookup(reply_port->value.as_send_port.id,
                            type->value.as_int32,
-                           name->value.as_string);
+                           name->value.as_string,
+                           timeout->value.as_int32);
             }
             return;
           }
 
         default:
           break;
           // Ignore invalid requests.
       }
     }
     Dart_CObject result;
@@ skipping 52 matching lines @@
     return parent_library;
   }
 
   result_code = Dart_SetNativeResolver(parent_library, ResolveName, NULL);
   if (Dart_IsError(result_code)) {
     return result_code;
   }
 
   return parent_library;
 }