| // 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 <map> |
| #include <vector> |
| |
| #include "base/memory/scoped_ptr.h" |
| #include "content/common/content_export.h" |
| #include "ipc/message_filter.h" |
| #include "media/midi/midi_port_info.h" |
| #include "media/midi/midi_result.h" |
| #include "third_party/WebKit/public/platform/WebMIDIAccessorClient.h" |
| |
| namespace base { |
| class MessageLoopProxy; |
| } |
| |
| namespace content { |
| |
| // MessageFilter that handles MIDI messages. |
| class CONTENT_EXPORT MidiMessageFilter : public IPC::MessageFilter { |
| public: |
| explicit MidiMessageFilter( |
| const scoped_refptr<base::MessageLoopProxy>& io_message_loop); |
| |
| // Each client registers for MIDI access here. |
| // If permission is granted, then the client's |
| // addInputPort() and addOutputPort() methods will be called, |
| // giving the client access to receive and send data. |
| void StartSession(blink::WebMIDIAccessorClient* client); |
| void RemoveClient(blink::WebMIDIAccessorClient* client); |
| |
| // A client will only be able to call this method if it has a suitable |
| // output port (from addOutputPort()). |
| void SendMidiData(uint32 port, |
| const uint8* data, |
| size_t length, |
| double timestamp); |
| |
| // IO message loop associated with this message filter. |
| scoped_refptr<base::MessageLoopProxy> io_message_loop() const { |
| return io_message_loop_; |
| } |
| |
| protected: |
| virtual ~MidiMessageFilter(); |
| |
| private: |
| // Sends an IPC message using |sender_|. |
| void Send(IPC::Message* message); |
| |
| // IPC::MessageFilter override. Called on |io_message_loop|. |
| virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE; |
| virtual void OnFilterAdded(IPC::Sender* sender) OVERRIDE; |
| virtual void OnFilterRemoved() OVERRIDE; |
| virtual void OnChannelClosing() OVERRIDE; |
| |
| // Called when the browser process has approved (or denied) access to |
| // MIDI hardware. |
| void OnSessionStarted(int client_id, |
| media::MidiResult result, |
| media::MidiPortInfoList inputs, |
| media::MidiPortInfoList outputs); |
| |
| // 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); |
| |
| void HandleSessionStarted(int client_id, |
| media::MidiResult result, |
| media::MidiPortInfoList inputs, |
| media::MidiPortInfoList outputs); |
| |
| void HandleDataReceived(uint32 port, |
| const std::vector<uint8>& data, |
| double timestamp); |
| |
| void StartSessionOnIOThread(int client_id); |
| |
| void SendMidiDataOnIOThread(uint32 port, |
| const std::vector<uint8>& data, |
| double timestamp); |
| |
| blink::WebMIDIAccessorClient* GetClientFromId(int client_id); |
| |
| // IPC sender for Send(); must only be accessed on |io_message_loop_|. |
| IPC::Sender* sender_; |
| |
| // Message loop on which IPC calls are driven. |
| const scoped_refptr<base::MessageLoopProxy> io_message_loop_; |
| |
| // Main thread's message loop. |
| scoped_refptr<base::MessageLoopProxy> main_message_loop_; |
| |
| // Keeps track of all MIDI clients. |
| // We map client to "client id" used to track permission. |
| // When access has been approved, we add the input and output ports to |
| // the client, allowing it to actually receive and send MIDI data. |
| typedef std::map<blink::WebMIDIAccessorClient*, int> ClientsMap; |
| ClientsMap clients_; |
| |
| // Dishes out client ids. |
| int next_available_id_; |
| |
| size_t unacknowledged_bytes_sent_; |
| |
| DISALLOW_COPY_AND_ASSIGN(MidiMessageFilter); |
| }; |
| |
| } // namespace content |
| |
| #endif // CONTENT_RENDERER_MEDIA_MIDI_MESSAGE_FILTER_H_ |