1 files changed, 64 insertions, 0 deletions
diff --git a/dom/midi/midirMIDIPlatformService.h b/dom/midi/midirMIDIPlatformService.h
new file mode 100644
index 0000000000..e204b5576a
--- /dev/null
+++ b/dom/midi/midirMIDIPlatformService.h
@@ -0,0 +1,64 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_midirMIDIPlatformService_h
+#define mozilla_dom_midirMIDIPlatformService_h
+
+#include "mozilla/StaticMutex.h"
+#include "mozilla/dom/MIDIPlatformService.h"
+#include "mozilla/dom/MIDITypes.h"
+#include "mozilla/dom/midi/midir_impl_ffi_generated.h"
+
+class nsIThread;
+struct MidirWrapper;
+
+namespace mozilla::dom {
+
+class MIDIPortInterface;
+
+/**
+ * Platform service implementation using the midir crate.
+ */
+class midirMIDIPlatformService : public MIDIPlatformService {
+ public:
+  midirMIDIPlatformService();
+  virtual void Init() override;
+  virtual void Refresh() override;
+  virtual void Open(MIDIPortParent* aPort) override;
+  virtual void Stop() override;
+  virtual void ScheduleSend(const nsAString& aPort) override;
+  virtual void ScheduleClose(MIDIPortParent* aPort) override;
+
+  void SendMessage(const nsAString& aPort, const MIDIMessage& aMessage);
+
+ private:
+  virtual ~midirMIDIPlatformService();
+
+  static void AddPort(const nsString* aId, const nsString* aName, bool aInput);
+  static void RemovePort(const nsString* aId, const nsString* aName,
+                         bool aInput);
+  static void CheckAndReceive(const nsString* aId, const uint8_t* aData,
+                              size_t aLength, const GeckoTimeStamp* aTimeStamp,
+                              uint64_t aMicros);
+
+  // Wrapper around the midir Rust implementation.
+  MidirWrapper* mImplementation;
+
+  // The midir backends can invoke CheckAndReceive on arbitrary background
+  // threads, and so we dispatch events from there to the owner task queue.
+  // It's a little ambiguous whether midir can ever invoke CheckAndReceive
+  // on one of its platform-specific background threads after we've dropped
+  // the main instance. Just in case, we use a static mutex to avoid a potential
+  // race with dropping the primary reference to the task queue via
+  // ClearOnShutdown.
+  static StaticMutex gOwnerThreadMutex;
+  static nsCOMPtr<nsISerialEventTarget> gOwnerThread
+      MOZ_GUARDED_BY(gOwnerThreadMutex);
+};
+
+}  // namespace mozilla::dom
+
+#endif  // mozilla_dom_midirMIDIPlatformService_h