media/midi/midi_manager_alsa.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_MIDI_MANAGER_ALSA_H_
   6 #define MEDIA_MIDI_MIDI_MANAGER_ALSA_H_
   7
   8 #include <alsa/asoundlib.h>
   9 #include <map>
  10 #include <vector>
  11
  12 #include "base/basictypes.h"
  13 #include "base/gtest_prod_util.h"
  14 #include "base/memory/scoped_ptr.h"
  15 #include "base/synchronization/lock.h"
  16 #include "base/threading/thread.h"
  17 #include "media/midi/midi_manager.h"
  18
  19 #if defined(USE_UDEV)
  20 #include "device/udev_linux/scoped_udev.h"
  21 #endif  // defined(USE_UDEV)
  22
  23 namespace media {
  24
  25 class MEDIA_EXPORT MidiManagerAlsa : public MidiManager {
  26  public:
  27   MidiManagerAlsa();
  28   ~MidiManagerAlsa() override;
  29
  30   // MidiManager implementation.
  31   void StartInitialization() override;
  32   void DispatchSendMidiData(MidiManagerClient* client,
  33                             uint32 port_index,
  34                             const std::vector<uint8>& data,
  35                             double timestamp) override;
  36
  37  private:
  38   FRIEND_TEST_ALL_PREFIXES(MidiManagerAlsaTest, ExtractManufacturer);
  39   FRIEND_TEST_ALL_PREFIXES(MidiManagerAlsaTest, UdevEscape);
  40
  41   class CardInfo {
  42    public:
  43     CardInfo(const MidiManagerAlsa* outer,
  44              const std::string& alsa_name, const std::string& alsa_longname,
  45              const std::string& alsa_driver, int card_index);
  46     ~CardInfo();
  47
  48     const std::string alsa_name() const;
  49     const std::string manufacturer() const;
  50     const std::string alsa_driver() const;
  51     const std::string udev_id_path() const;
  52     const std::string udev_id_id() const;
  53
  54    private:
  55     FRIEND_TEST_ALL_PREFIXES(MidiManagerAlsaTest, ExtractManufacturer);
  56     FRIEND_TEST_ALL_PREFIXES(MidiManagerAlsaTest, UdevEscape);
  57
  58     // Extracts the manufacturer using heuristics and a variety of sources.
  59     static std::string ExtractManufacturerString(
  60         const std::string& udev_id_vendor,
  61         const std::string& udev_id_vendor_id,
  62         const std::string& udev_id_vendor_from_database,
  63         const std::string& alsa_name,
  64         const std::string& alsa_longname);
  65
  66     std::string alsa_name_;
  67     std::string manufacturer_;
  68     std::string alsa_driver_;
  69     std::string udev_id_path_;
  70     std::string udev_id_id_;
  71   };
  72
  73   // An internal callback that runs on MidiSendThread.
  74   void SendMidiData(uint32 port_index,
  75                     const std::vector<uint8>& data);
  76
  77   void EventReset();
  78   void EventLoop();
  79
  80   // Alsa seq handles.
  81   snd_seq_t* in_client_;
  82   snd_seq_t* out_client_;
  83   int out_client_id_;
  84
  85   // One input port, many output ports.
  86   int in_port_;
  87   std::vector<int> out_ports_;
  88
  89   // Mapping from Alsa client:port to our index.
  90   typedef std::map<int, uint32> SourceMap;
  91   SourceMap source_map_;
  92
  93   // Alsa event <-> MIDI coders.
  94   snd_midi_event_t* decoder_;
  95   typedef std::vector<snd_midi_event_t*> EncoderList;
  96   EncoderList encoders_;
  97
  98   // udev, for querying hardware devices.
  99 #if defined(USE_UDEV)
 100   device::ScopedUdevPtr udev_;
 101 #endif  // defined(USE_UDEV)
 102
 103   base::Thread send_thread_;
 104   base::Thread event_thread_;
 105
 106   bool event_thread_shutdown_; // guarded by shutdown_lock_
 107   base::Lock shutdown_lock_; // guards event_thread_shutdown_
 108
 109   DISALLOW_COPY_AND_ASSIGN(MidiManagerAlsa);
 110 };
 111
 112 }  // namespace media
 113
 114 #endif  // MEDIA_MIDI_MIDI_MANAGER_ALSA_H_