blob: 55e131054ebd42a10dcd3bf540bc6f32e33f23e0 [file] [log] [blame] [edit]
// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef IPC_MESSAGE_FILTER_H_
#define IPC_MESSAGE_FILTER_H_
#include <stdint.h>
#include <vector>
#include "base/component_export.h"
#include "base/memory/ref_counted.h"
#include "ipc/ipc_channel.h"
namespace IPC {
class Message;
// A class that receives messages on the thread where the IPC channel is
// running. It can choose to prevent the default action for an IPC message.
class COMPONENT_EXPORT(IPC) MessageFilter
: public base::RefCountedThreadSafe<MessageFilter> {
public:
MessageFilter();
// Called on the background thread to provide the filter with access to the
// channel. Called when the IPC channel is initialized or when AddFilter
// is called if the channel is already initialized.
virtual void OnFilterAdded(Channel* channel);
// Called on the background thread when the filter has been removed from
// the ChannelProxy and when the Channel is closing. After a filter is
// removed, it will not be called again.
virtual void OnFilterRemoved();
// Called to inform the filter that the IPC channel is connected and we
// have received the internal Hello message from the peer.
virtual void OnChannelConnected(int32_t peer_pid);
// Called when there is an error on the channel, typically that the channel
// has been closed.
virtual void OnChannelError();
// Called to inform the filter that the IPC channel will be destroyed.
// OnFilterRemoved is called immediately after this.
virtual void OnChannelClosing();
// Return true to indicate that the message was handled, or false to let
// the message be handled in the default way.
virtual bool OnMessageReceived(const Message& message);
// Called to query the Message classes supported by the filter. Return
// false to indicate that all message types should reach the filter, or true
// if the resulting contents of |supported_message_classes| may be used to
// selectively offer messages of a particular class to the filter.
virtual bool GetSupportedMessageClasses(
std::vector<uint32_t>* supported_message_classes) const;
protected:
virtual ~MessageFilter();
private:
friend class base::RefCountedThreadSafe<MessageFilter>;
};
} // namespace IPC
#endif // IPC_MESSAGE_FILTER_H_