media/midi/usb_midi_output_stream.h

   1 // Copyright 2014 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 MEDIA_MIDI_USB_MIDI_OUTPUT_STREAM_H_
   6 #define MEDIA_MIDI_USB_MIDI_OUTPUT_STREAM_H_
   7
   8 #include <vector>
   9
  10 #include "base/basictypes.h"
  11 #include "media/base/media_export.h"
  12 #include "media/midi/usb_midi_jack.h"
  13
  14 namespace media {
  15
  16 // UsbMidiOutputStream converts MIDI data to USB-MIDI data.
  17 // See "USB Device Class Definition for MIDI Devices" Release 1.0,
  18 // Section 4 "USB-MIDI Event Packets" for details.
  19 class MEDIA_EXPORT UsbMidiOutputStream {
  20  public:
  21   explicit UsbMidiOutputStream(const UsbMidiJack& jack);
  22
  23   // Converts |data| to USB-MIDI data and send it to the jack.
  24   void Send(const std::vector<uint8>& data);
  25
  26   const UsbMidiJack& jack() const { return jack_; }
  27
  28  private:
  29   size_t GetSize(const std::vector<uint8>& data) const;
  30   uint8_t Get(const std::vector<uint8>& data, size_t index) const;
  31
  32   bool PushSysExMessage(const std::vector<uint8>& data,
  33                         size_t* current,
  34                         std::vector<uint8>* data_to_send);
  35   bool PushSysCommonMessage(const std::vector<uint8>& data,
  36                             size_t* current,
  37                             std::vector<uint8>* data_to_send);
  38   void PushSysRTMessage(const std::vector<uint8>& data,
  39                         size_t* current,
  40                         std::vector<uint8>* data_to_send);
  41   bool PushChannelMessage(const std::vector<uint8>& data,
  42                           size_t* current,
  43                           std::vector<uint8>* data_to_send);
  44
  45   static const size_t kPacketContentSize = 3;
  46
  47   UsbMidiJack jack_;
  48   size_t pending_size_;
  49   uint8 pending_data_[kPacketContentSize];
  50   bool is_sending_sysex_;
  51
  52   DISALLOW_COPY_AND_ASSIGN(UsbMidiOutputStream);
  53 };
  54
  55 }  // namespace media
  56
  57 #endif  // MEDIA_MIDI_USB_MIDI_OUTPUT_STREAM_H_