1 files changed, 58 insertions, 0 deletions
diff --git a/dom/midi/MIDIMessageQueue.h b/dom/midi/MIDIMessageQueue.h
new file mode 100644
index 0000000000..cadfc1b249
--- /dev/null
+++ b/dom/midi/MIDIMessageQueue.h
@@ -0,0 +1,58 @@
+/* -*- 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_MIDIMessageQueue_h
+#define mozilla_dom_MIDIMessageQueue_h
+
+#include "mozilla/Mutex.h"
+#include "nsTArray.h"
+
+// XXX Avoid including this here by moving function implementations to the cpp
+// file.
+#include "mozilla/dom/MIDITypes.h"
+
+namespace mozilla {
+
+class TimeStamp;
+
+namespace dom {
+
+class MIDIMessage;
+
+/**
+ * Since some MIDI Messages can be scheduled to be sent in the future, the
+ * MIDIMessageQueue is responsible for making sure all MIDI messages are
+ * scheduled and sent in order.
+ */
+class MIDIMessageQueue {
+ public:
+  MIDIMessageQueue();
+  ~MIDIMessageQueue() = default;
+  // Adds an array of possibly out-of-order messages to our queue.
+  void Add(nsTArray<MIDIMessage>& aMsg);
+  // Retrieve all pending messages before the time specified.
+  void GetMessagesBefore(TimeStamp aTimestamp,
+                         nsTArray<MIDIMessage>& aMsgQueue);
+  // Get all pending messages.
+  void GetMessages(nsTArray<MIDIMessage>& aMsgQueue);
+  // Erase all pending messages.
+  void Clear();
+  // Erase all pending messages that would be sent in the future. Useful for
+  // when ports are closed, as we must send all messages with timestamps in the
+  // past.
+  void ClearAfterNow();
+
+ private:
+  // Array of messages to be sent.
+  nsTArray<MIDIMessage> mMessageQueue;
+  // Mutex for coordinating cross thread array access.
+  Mutex mMutex MOZ_UNANNOTATED;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_MIDIMessageQueue_h