Web MIDI: distributes MIDIPort information asynchronously

content/renderer/media/midi_message_filter.h

 // Copyright (c) 2013 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 CONTENT_RENDERER_MEDIA_MIDI_MESSAGE_FILTER_H_
 #define CONTENT_RENDERER_MEDIA_MIDI_MESSAGE_FILTER_H_
 
 #include <set>
 #include <vector>
 
@@ skipping 49 matching lines @@
   void Send(IPC::Message* message);
 
   // IPC::MessageFilter override. Called on |io_message_loop|.
   bool OnMessageReceived(const IPC::Message& message) override;
   void OnFilterAdded(IPC::Sender* sender) override;
   void OnFilterRemoved() override;
   void OnChannelClosing() override;
 
   // Called when the browser process has approved (or denied) access to
   // MIDI hardware.
-  // TODO(toyoshim): MidiPortInfoList objects should be notified separately
-  // port by port.
-  void OnSessionStarted(media::MidiResult result,
-                        media::MidiPortInfoList inputs,
-                        media::MidiPortInfoList outputs);
+  void OnSessionStarted(media::MidiResult result);
+
+  // These functions are called in 2 cases:
+  //  (1) Just before calling |OnSessionStarted|, to notify the recipient about
+  //      existing ports.
+  //  (2) To notify the recipient that a new device was connected and that new
+  //      ports have been created.
+  void OnAddInputPort(media::MidiPortInfo info);
+  void OnAddOutputPort(media::MidiPortInfo info);
 
   // Called when the browser process has sent MIDI data containing one or
   // more messages.
   void OnDataReceived(uint32 port,
                       const std::vector<uint8>& data,
                       double timestamp);
 
   // From time-to-time, the browser incrementally informs us of how many bytes
   // it has successfully sent. This is part of our throttling process to avoid
   // sending too much data before knowing how much has already been sent.
   void OnAcknowledgeSentData(size_t bytes_sent);
 
   // Following methods, Handle*, run on |main_message_loop_|.
   void HandleClientAdded(media::MidiResult result);
 
+  void HandleAddInputPort(media::MidiPortInfo info);
+  void HandleAddOutputPort(media::MidiPortInfo info);
+
   void HandleDataReceived(uint32 port,
                           const std::vector<uint8>& data,
                           double timestamp);
 
   void HandleAckknowledgeSentData(size_t bytes_sent);
 
   // IPC sender for Send(); must only be accessed on |io_message_loop_|.
   IPC::Sender* sender_;
 
   // Message loop on which IPC calls are driven.
@@ skipping 22 matching lines @@
   media::MidiPortInfoList outputs_;
 
   size_t unacknowledged_bytes_sent_;
 
   DISALLOW_COPY_AND_ASSIGN(MidiMessageFilter);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_MIDI_MESSAGE_FILTER_H_