ppapi/proxy/plugin_message_filter.h

   1 // Copyright (c) 2011 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 PPAPI_PROXY_PLUGIN_MESSAGE_FILTER_H_
   6 #define PPAPI_PROXY_PLUGIN_MESSAGE_FILTER_H_
   7
   8 #include <set>
   9
  10 #include "base/compiler_specific.h"
  11 #include "ipc/ipc_channel_proxy.h"
  12 #include "ipc/ipc_sender.h"
  13 #include "ppapi/c/pp_instance.h"
  14
  15 namespace ppapi {
  16 namespace proxy {
  17
  18 // Listens for messages on the I/O thread of the plugin and handles some of
  19 // them to avoid needing to block on the plugin.
  20 //
  21 // There is one instance of this class for each renderer channel (same as for
  22 // the PluginDispatchers).
  23 class PluginMessageFilter : public IPC::ChannelProxy::MessageFilter,
  24                             public IPC::Sender {
  25  public:
  26   // The input is a pointer to a set that will be used to uniquify PP_Instances
  27   // across all renderer channels. The same pointer should be passed to each
  28   // MessageFilter to ensure uniqueness, and the value should outlive this
  29   // class.
  30   PluginMessageFilter(std::set<PP_Instance>* seen_instance_ids);
  31   virtual ~PluginMessageFilter();
  32
  33   // MessageFilter implementation.
  34   virtual void OnFilterAdded(IPC::Channel* channel) OVERRIDE;
  35   virtual void OnFilterRemoved() OVERRIDE;
  36   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
  37
  38   // IPC::Sender implementation.
  39   virtual bool Send(IPC::Message* msg) OVERRIDE;
  40
  41  private:
  42   void OnMsgReserveInstanceId(PP_Instance instance, bool* usable);
  43
  44   // All instance IDs every queried by any renderer on this plugin. This is
  45   // used to make sure that new instance IDs are unique. This is a non-owning
  46   // pointer, it will be managed by the later that creates this class.
  47   std::set<PP_Instance>* seen_instance_ids_;
  48
  49   // The IPC channel to the renderer. May be NULL if we're not currently
  50   // attached as a filter.
  51   IPC::Channel* channel_;
  52 };
  53
  54 }  // namespace proxy
  55 }  // namespace ppapi
  56
  57 #endif  // PPAPI_PROXY_PLUGIN_MESSAGE_FILTER_H_