1 // Copyright 2014 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef MOJO_PUBLIC_CPP_BINDINGS_MESSAGE_FILTER_H_ 6 #define MOJO_PUBLIC_CPP_BINDINGS_MESSAGE_FILTER_H_ 7 8 #include "mojo/public/cpp/bindings/message.h" 9 #include "mojo/public/cpp/system/macros.h" 10 11 namespace mojo { 12 13 // This class is the base class for message filters. Subclasses should 14 // implement the pure virtual method Accept() inherited from MessageReceiver to 15 // process messages and/or forward them to |sink_|. 16 class MessageFilter : public MessageReceiver { 17 public: 18 // Doesn't take ownership of |sink|. Therefore |sink| has to stay alive while 19 // this object is alive. 20 explicit MessageFilter(MessageReceiver* sink = NULL); 21 virtual ~MessageFilter(); 22 set_sink(MessageReceiver * sink)23 void set_sink(MessageReceiver* sink) { sink_ = sink; } 24 25 protected: 26 MessageReceiver* sink_; 27 }; 28 29 // A trivial filter that simply forwards every message it receives to |sink_|. 30 class PassThroughFilter : public MessageFilter { 31 public: 32 explicit PassThroughFilter(MessageReceiver* sink = NULL); 33 34 virtual bool Accept(Message* message) MOJO_OVERRIDE; 35 }; 36 37 } // namespace mojo 38 39 #endif // MOJO_PUBLIC_CPP_BINDINGS_LIB_MESSAGE_FILTER_H_ 40