1 files changed, 127 insertions, 0 deletions
diff --git a/dom/media/webaudio/MediaStreamAudioSourceNode.h b/dom/media/webaudio/MediaStreamAudioSourceNode.h
new file mode 100644
index 0000000000..1875fc2e83
--- /dev/null
+++ b/dom/media/webaudio/MediaStreamAudioSourceNode.h
@@ -0,0 +1,127 @@
+/* -*- 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 MediaStreamAudioSourceNode_h_
+#define MediaStreamAudioSourceNode_h_
+
+#include "AudioNode.h"
+#include "AudioNodeEngine.h"
+#include "DOMMediaStream.h"
+#include "PrincipalChangeObserver.h"
+
+namespace mozilla::dom {
+
+class AudioContext;
+struct MediaStreamAudioSourceOptions;
+
+class MediaStreamAudioSourceNodeEngine final : public AudioNodeEngine {
+ public:
+  explicit MediaStreamAudioSourceNodeEngine(AudioNode* aNode)
+      : AudioNodeEngine(aNode), mEnabled(false) {}
+
+  bool IsEnabled() const { return mEnabled; }
+  enum Parameters { ENABLE };
+  void SetInt32Parameter(uint32_t aIndex, int32_t aValue) override {
+    switch (aIndex) {
+      case ENABLE:
+        mEnabled = !!aValue;
+        break;
+      default:
+        NS_ERROR("MediaStreamAudioSourceNodeEngine bad parameter index");
+    }
+  }
+
+ private:
+  bool mEnabled;
+};
+
+class MediaStreamAudioSourceNode
+    : public AudioNode,
+      public DOMMediaStream::TrackListener,
+      public PrincipalChangeObserver<MediaStreamTrack> {
+ public:
+  static already_AddRefed<MediaStreamAudioSourceNode> Create(
+      AudioContext& aContext, const MediaStreamAudioSourceOptions& aOptions,
+      ErrorResult& aRv);
+
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(MediaStreamAudioSourceNode,
+                                           AudioNode)
+
+  static already_AddRefed<MediaStreamAudioSourceNode> Constructor(
+      const GlobalObject& aGlobal, AudioContext& aAudioContext,
+      const MediaStreamAudioSourceOptions& aOptions, ErrorResult& aRv) {
+    return Create(aAudioContext, aOptions, aRv);
+  }
+
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
+  void DestroyMediaTrack() override;
+
+  uint16_t NumberOfInputs() const override { return 0; }
+
+  DOMMediaStream* GetMediaStream() { return mInputStream; }
+
+  const char* NodeType() const override { return "MediaStreamAudioSourceNode"; }
+
+  virtual const char* CrossOriginErrorString() const {
+    return "MediaStreamAudioSourceNodeCrossOrigin";
+  }
+
+  size_t SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const override;
+  size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const override;
+
+  // Attaches to aTrack so that its audio content will be used as input.
+  void AttachToTrack(const RefPtr<MediaStreamTrack>& aTrack, ErrorResult& aRv);
+
+  // Detaches from the currently attached track if there is one.
+  void DetachFromTrack();
+
+  // Attaches to the first audio track in the MediaStream, when the tracks are
+  // ordered by id.
+  void AttachToRightTrack(const RefPtr<DOMMediaStream>& aMediaStream,
+                          ErrorResult& aRv);
+
+  // From DOMMediaStream::TrackListener.
+  void NotifyTrackAdded(const RefPtr<MediaStreamTrack>& aTrack) override;
+  void NotifyTrackRemoved(const RefPtr<MediaStreamTrack>& aTrack) override;
+  void NotifyAudible() override;
+
+  // From PrincipalChangeObserver<MediaStreamTrack>.
+  void PrincipalChanged(MediaStreamTrack* aMediaStreamTrack) override;
+
+  // This allows implementing the correct behaviour for both
+  // MediaElementAudioSourceNode and MediaStreamAudioSourceNode, that have most
+  // of their behaviour shared.
+  enum TrackChangeBehavior {
+    // MediaStreamAudioSourceNode locks on the track it picked, and never
+    // changes.
+    LockOnTrackPicked,
+    // MediaElementAudioSourceNode can change track, depending on what the
+    // HTMLMediaElement does.
+    FollowChanges
+  };
+
+ protected:
+  MediaStreamAudioSourceNode(AudioContext* aContext,
+                             TrackChangeBehavior aBehavior);
+  void Init(DOMMediaStream& aMediaStream, ErrorResult& aRv);
+  virtual void Destroy();
+  virtual ~MediaStreamAudioSourceNode();
+
+ private:
+  const TrackChangeBehavior mBehavior;
+  RefPtr<MediaInputPort> mInputPort;
+  RefPtr<DOMMediaStream> mInputStream;
+
+  // On construction we set this to the first audio track of mInputStream.
+  RefPtr<MediaStreamTrack> mInputTrack;
+};
+
+}  // namespace mozilla::dom
+
+#endif