dom/midi/midirMIDIPlatformService.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim:set ts=2 sw=2 sts=2 et cindent: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_dom_midirMIDIPlatformService_h
   8 #define mozilla_dom_midirMIDIPlatformService_h
   9
  10 #include "mozilla/StaticMutex.h"
  11 #include "mozilla/dom/MIDIPlatformService.h"
  12 #include "mozilla/dom/MIDITypes.h"
  13 #include "mozilla/dom/midi/midir_impl_ffi_generated.h"
  14
  15 class nsIThread;
  16 struct MidirWrapper;
  17
  18 namespace mozilla::dom {
  19
  20 class MIDIPortInterface;
  21
  22 /**
  23  * Platform service implementation using the midir crate.
  24  */
  25 class midirMIDIPlatformService : public MIDIPlatformService {
  26  public:
  27   midirMIDIPlatformService();
  28   virtual void Init() override;
  29   virtual void Refresh() override;
  30   virtual void Open(MIDIPortParent* aPort) override;
  31   virtual void Stop() override;
  32   virtual void ScheduleSend(const nsAString& aPort) override;
  33   virtual void ScheduleClose(MIDIPortParent* aPort) override;
  34
  35   void SendMessage(const nsAString& aPort, const MIDIMessage& aMessage);
  36
  37  private:
  38   virtual ~midirMIDIPlatformService();
  39
  40   static void AddPort(const nsString* aId, const nsString* aName, bool aInput);
  41   static void RemovePort(const nsString* aId, const nsString* aName,
  42                          bool aInput);
  43   static void CheckAndReceive(const nsString* aId, const uint8_t* aData,
  44                               size_t aLength, const GeckoTimeStamp* aTimeStamp,
  45                               uint64_t aMicros);
  46
  47   // Wrapper around the midir Rust implementation.
  48   MidirWrapper* mImplementation;
  49
  50   // The midir backends can invoke CheckAndReceive on arbitrary background
  51   // threads, and so we dispatch events from there to the owner task queue.
  52   // It's a little ambiguous whether midir can ever invoke CheckAndReceive
  53   // on one of its platform-specific background threads after we've dropped
  54   // the main instance. Just in case, we use a static mutex to avoid a potential
  55   // race with dropping the primary reference to the task queue via
  56   // ClearOnShutdown.
  57   static StaticMutex gOwnerThreadMutex;
  58   static nsCOMPtr<nsISerialEventTarget> gOwnerThread
  59       MOZ_GUARDED_BY(gOwnerThreadMutex);
  60 };
  61
  62 }  // namespace mozilla::dom
  63
  64 #endif  // mozilla_dom_midirMIDIPlatformService_h