Web MIDI: implement receiving for dynamic manager instantiation on Windows

media/midi/dynamically_initialized_midi_manager_win.h

Index: media/midi/dynamically_initialized_midi_manager_win.h
diff --git a/media/midi/dynamically_initialized_midi_manager_win.h b/media/midi/dynamically_initialized_midi_manager_win.h
index 5c4f65a4010db484b09ff50fa1f6274fdd6fe8a8..fc617c9288987c93473e96ff2f8f317c7996716d 100644
--- a/media/midi/dynamically_initialized_midi_manager_win.h
+++ b/media/midi/dynamically_initialized_midi_manager_win.h
@@ -25,9 +25,24 @@ class DynamicallyInitializedMidiManagerWin final
     : public MidiManager,
       public base::SystemMonitor::DevicesChangedObserver {
  public:
+  class PortManager;
+
   explicit DynamicallyInitializedMidiManagerWin(MidiService* service);
   ~DynamicallyInitializedMidiManagerWin() override;
 
+  // Returns PortManager that implements interfaces to help implementation.
+  // This hides Windows specific structures, i.e. HMIDIIN in the header.
+  PortManager* port_manager() { return port_manager_.get(); }
+
+  // Handles MIDI inport event posted from a thread system provides.
+  void ReceiveMidiData(uint32_t index,
+                       const std::vector<uint8_t>& data,
+                       base::TimeTicks time);
+
+  // Posts a task to TaskRunner, and ensures that the instance keeps alive while

[Takashi Toyoshima, 2017/02/24 08:53:34]

Move from private to public so to use this from PortManager.
Another choice is to make PortManager friend class.

[yhirano, 2017/02/24 12:22:58]

PortManager is an inner class so it can access to private members.

[Takashi Toyoshima, 2017/02/27 06:44:49]

Oh, thanks.
My understanding around access specifiers looks not clear.

And, my previous comment wasn't also accurate.
This is used with PortManager's method, but called outside PortManager, but in a
static callback function. So, this still needs to be public.

But... let me try converting the function to PortManager's static method. That
would help me to avoid making these methods public.

+  // the task is running.
+  void PostTask(const base::Closure&);
+
   // Posts a reply task to the I/O thread that hosts MidiManager instance, runs
   // it safely, and ensures that the instance keeps alive while the task is
   // running.
@@ -48,10 +63,6 @@ class DynamicallyInitializedMidiManagerWin final
   class InPort;
   class OutPort;
 
-  // Posts a task to TaskRunner, and ensures that the instance keeps alive while
-  // the task is running.
-  void PostTask(const base::Closure&);
-
   // Initializes instance asynchronously on TaskRunner.
   void InitializeOnTaskRunner();
 
@@ -71,11 +82,9 @@ class DynamicallyInitializedMidiManagerWin final
   // Keeps a TaskRunner for the I/O thread.
   scoped_refptr<base::SingleThreadTaskRunner> thread_runner_;
 
-  // Following members should be accessed only on TaskRunner.
-
-  // Holds all MIDI input or output ports connected once.
-  std::vector<std::unique_ptr<InPort>> input_ports_;
-  std::vector<std::unique_ptr<OutPort>> output_ports_;
+  // Manages platform dependent implementation for port managegent. Should be
+  // accessed with the task lock.
+  std::unique_ptr<PortManager> port_manager_;
 
   DISALLOW_COPY_AND_ASSIGN(DynamicallyInitializedMidiManagerWin);
 };