Bug 834929 - Part 2: Remove FloatArrayWrapper and just copy the curve array when needed; r=roc

content/media/webaudio/AudioEventTimeline.h

@@ -20,15 +20,10 @@ namespace dom {
  * This class will be instantiated with different template arguments for testing and
  * production code.
  *
- * FloatArrayWrapper is a type which satisfies the following:
- *  - Is copy-constructible.
- *  - Implements a Data() method returning a float*, representing an array.
- *  - Implements a Length() method returning a uint32_t, representing the array length.
- *  - Implements an inited() method returning true for valid objects.
  * ErrorResult is a type which satisfies the following:
  *  - Implements a Throw() method taking an nsresult argument, representing an error code.
  */
-template <class FloatArrayWrapper, class ErrorResult>
+template <class ErrorResult>
 class AudioEventTimeline
 {
 private:
@@ -42,16 +37,15 @@ private:
     };
 
     Event(Type aType, double aTime, float aValue, double aTimeConstant = 0.0,
-          float aDuration = 0.0, FloatArrayWrapper aCurve = FloatArrayWrapper())
+          float aDuration = 0.0, float* aCurve = nullptr, uint32_t aCurveLength = 0)
       : mType(aType)
       , mValue(aValue)
       , mTime(aTime)
       , mTimeConstant(aTimeConstant)
       , mDuration(aDuration)
+      , mCurve(aCurve)
+      , mCurveLength(aCurveLength)
     {
-      if (aCurve.inited()) {
-        mCurve = aCurve;
-      }
     }
 
     bool IsValid() const
@@ -67,7 +61,8 @@ private:
     double mTime;
     double mTimeConstant;
     double mDuration;
-    FloatArrayWrapper mCurve;
+    float* mCurve;
+    uint32_t mCurveLength;
 
   private:
     static bool IsValid(float value)
@@ -122,10 +117,11 @@ public:
     InsertEvent(Event(Event::SetTarget, aStartTime, aTarget, aTimeConstant), aRv);
   }
 
-  void SetValueCurveAtTime(const FloatArrayWrapper& aValues, double aStartTime, double aDuration, ErrorResult& aRv)
+  void SetValueCurveAtTime(const float* aValues, uint32_t aValuesLength, double aStartTime, double aDuration, ErrorResult& aRv)
   {
     // TODO: implement
-    // InsertEvent(Event(Event::SetValueCurve, aStartTime, 0.0f, 0.0f, aDuration, aValues), aRv);
+    // Note that we will need to copy the buffer here.
+    // InsertEvent(Event(Event::SetValueCurve, aStartTime, 0.0f, 0.0f, aDuration, aValues, aValuesLength), aRv);
   }
 
   void CancelScheduledValues(double aStartTime)

content/media/webaudio/AudioParam.h

@@ -26,57 +26,7 @@ class ErrorResult;
 
 namespace dom {
 
-namespace detail {
-
-// This class wraps a JS typed array so that AudioEventTimeline does not need
-// to know about JSObjects directly.
-class FloatArrayWrapper
-{
-public:
-  FloatArrayWrapper() // creates an uninitialized object
-  {
-  }
-  FloatArrayWrapper(const Float32Array& array)
-  {
-    mArray.construct(array);
-  }
-  FloatArrayWrapper(const FloatArrayWrapper& rhs)
-  {
-    MOZ_ASSERT(!rhs.mArray.empty());
-    mArray.construct(rhs.mArray.ref());
-  }
-
-  FloatArrayWrapper& operator=(const FloatArrayWrapper& rhs)
-  {
-    MOZ_ASSERT(!rhs.mArray.empty());
-    mArray.destroyIfConstructed();
-    mArray.construct(rhs.mArray.ref());
-    return *this;
-  }
-
-  // Expose the API used by AudioEventTimeline
-  float* Data() const
-  {
-    MOZ_ASSERT(inited());
-    return mArray.ref().Data();
-  }
-  uint32_t Length() const
-  {
-    MOZ_ASSERT(inited());
-    return mArray.ref().Length();
-  }
-  bool inited() const
-  {
-    return !mArray.empty();
-  }
-
-private:
-  Maybe<Float32Array> mArray;
-};
-
-}
-
-typedef AudioEventTimeline<detail::FloatArrayWrapper, ErrorResult> AudioParamTimeline;
+typedef AudioEventTimeline<ErrorResult> AudioParamTimeline;
 
 class AudioParam MOZ_FINAL : public nsWrapperCache,
                              public EnableWebAudioCheck,
@@ -104,7 +54,7 @@ public:
   // object.
   void SetValueCurveAtTime(JSContext* cx, const Float32Array& aValues, double aStartTime, double aDuration, ErrorResult& aRv)
   {
-    AudioParamTimeline::SetValueCurveAtTime(detail::FloatArrayWrapper(aValues),
+    AudioParamTimeline::SetValueCurveAtTime(aValues.Data(), aValues.Length(),
                                             aStartTime, aDuration, aRv);
   }
 

content/media/webaudio/compiledtest/TestAudioEventTimeline.cpp

@@ -53,24 +53,6 @@ void is(const float& a, const float& b, const char* msg)
   ok(fabsf(a - b) < kEpsilon, ss.str().c_str());
 }
 
-class FloatArrayMock
-{
-public:
-  // This implementation is not used for now, so let's just return dummy values.
-  float* Data() const
-  {
-    return nullptr;
-  }
-  uint32_t Length() const
-  {
-    return 0;
-  }
-  bool inited() const
-  {
-    return true;
-  }
-};
-
 class ErrorResultMock
 {
 public:
@@ -92,7 +74,7 @@ private:
   nsresult mRv;
 };
 
-typedef AudioEventTimeline<FloatArrayMock, ErrorResultMock> Timeline;
+typedef AudioEventTimeline<ErrorResultMock> Timeline;
 
 void TestSpecExample()
 {