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/midi/usb_midi_export.h"
  12 #include "media/midi/usb_midi_jack.h"
  13
  14 namespace media {
  15 namespace midi {
  16
  17 // UsbMidiOutputStream converts MIDI data to USB-MIDI data.
  18 // See "USB Device Class Definition for MIDI Devices" Release 1.0,
  19 // Section 4 "USB-MIDI Event Packets" for details.
  20 class USB_MIDI_EXPORT UsbMidiOutputStream {
  21  public:
  22   explicit UsbMidiOutputStream(const UsbMidiJack& jack);
  23
  24   // Converts |data| to USB-MIDI data and send it to the jack.
  25   void Send(const std::vector<uint8>& data);
  26
  27   const UsbMidiJack& jack() const { return jack_; }
  28
  29  private:
  30   size_t GetSize(const std::vector<uint8>& data) const;
  31   uint8_t Get(const std::vector<uint8>& data, size_t index) const;
  32
  33   bool PushSysExMessage(const std::vector<uint8>& data,
  34                         size_t* current,
  35                         std::vector<uint8>* data_to_send);
  36   bool PushSysCommonMessage(const std::vector<uint8>& data,
  37                             size_t* current,
  38                             std::vector<uint8>* data_to_send);
  39   void PushSysRTMessage(const std::vector<uint8>& data,
  40                         size_t* current,
  41                         std::vector<uint8>* data_to_send);
  42   bool PushChannelMessage(const std::vector<uint8>& data,
  43                           size_t* current,
  44                           std::vector<uint8>* data_to_send);
  45
  46   static const size_t kPacketContentSize = 3;
  47
  48   UsbMidiJack jack_;
  49   size_t pending_size_;
  50   uint8 pending_data_[kPacketContentSize];
  51   bool is_sending_sysex_;
  52
  53   DISALLOW_COPY_AND_ASSIGN(UsbMidiOutputStream);
  54 };
  55
  56 }  // namespace midi
  57 }  // namespace media
  58
  59 #endif  // MEDIA_MIDI_USB_MIDI_OUTPUT_STREAM_H_