// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef IPC_IPC_LISTENER_H_
#define IPC_IPC_LISTENER_H_

#include "base/basictypes.h"
#include "build/build_config.h"
#include "ipc/ipc_export.h"

namespace IPC {

class Message;

// Implemented by consumers of a Channel to receive messages.
class IPC_EXPORT Listener {
 public:
  // Called when a message is received.  Returns true iff the message was
  // handled.
  virtual bool OnMessageReceived(const Message& message) = 0;

  // Called when the channel is connected and we have received the internal
  // Hello message from the peer.
  virtual void OnChannelConnected(int32 peer_pid) {}

  // Called when an error is detected that causes the channel to close.
  // This method is not called when a channel is closed normally.
  virtual void OnChannelError() {}

  // Called when a message's deserialization failed.
  virtual void OnBadMessageReceived(const Message& message) {}

#if defined(OS_POSIX)
  // Called on the server side when a channel that listens for connections
  // denies an attempt to connect.
  virtual void OnChannelDenied() {}

  // Called on the server side when a channel that listens for connections
  // has an error that causes the listening channel to close.
  virtual void OnChannelListenError() {}
#endif  // OS_POSIX

 protected:
  virtual ~Listener() {}
};

}  // namespace IPC

#endif  // IPC_IPC_LISTENER_H_