Implement IIRFilter node for WebAudio.

third_party/WebKit/Source/modules/webaudio/IIRFilterNode.cpp

Index: third_party/WebKit/Source/modules/webaudio/IIRFilterNode.cpp
diff --git a/third_party/WebKit/Source/modules/webaudio/IIRFilterNode.cpp b/third_party/WebKit/Source/modules/webaudio/IIRFilterNode.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..0cf20480324d354b2f7beddd9f74b94e074f3051
--- /dev/null
+++ b/third_party/WebKit/Source/modules/webaudio/IIRFilterNode.cpp
@@ -0,0 +1,80 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "modules/webaudio/IIRFilterNode.h"
+
+#include "bindings/core/v8/ExceptionMessages.h"
+#include "bindings/core/v8/ExceptionState.h"
+#include "core/dom/ExceptionCode.h"
+#include "modules/webaudio/AudioBasicProcessorHandler.h"
+
+namespace blink {
+
+IIRFilterNode::IIRFilterNode(AbstractAudioContext& context, float sampleRate, const Vector<double> feedforwardCoef, const Vector<double> feedbackCoef)
+    : AudioNode(context)
+{
+    setHandler(AudioBasicProcessorHandler::create(
+        AudioHandler::NodeTypeIIRFilter, *this, sampleRate,
+        adoptPtr(new IIRProcessor(sampleRate, 1, feedforwardCoef, feedbackCoef))));
+}
+
+DEFINE_TRACE(IIRFilterNode)
+{
+    AudioNode::trace(visitor);
+}
+
+IIRProcessor* IIRFilterNode::iirProcessor() const
+{
+    return static_cast<IIRProcessor*>(static_cast<AudioBasicProcessorHandler&>(handler()).processor());
+}
+
+void IIRFilterNode::getFrequencyResponse(const DOMFloat32Array* frequencyHz, DOMFloat32Array* magResponse, DOMFloat32Array* phaseResponse, ExceptionState& exceptionState)
+{
+    if (!frequencyHz) {
+        exceptionState.throwDOMException(
+            NotSupportedError,
+            "frequencyHz array cannot be null");
+        return;
+    }
+
+    if (!magResponse) {
+        exceptionState.throwDOMException(
+            NotSupportedError,
+            "magResponse array cannot be null");
+        return;
+    }
+
+    if (!phaseResponse) {
+        exceptionState.throwDOMException(
+            NotSupportedError,
+            "phaseResponse array cannot be null");
+        return;
+    }
+
+    unsigned frequencyHzLength = frequencyHz->length();
+
+    if (magResponse->length() < frequencyHzLength) {
+        exceptionState.throwDOMException(
+            NotSupportedError,
+            ExceptionMessages::indexExceedsMinimumBound(
+                "magResponse length",
+                magResponse->length(),
+                frequencyHzLength));
+        return;
+    }
+
+    if (phaseResponse->length() < frequencyHzLength) {
+        exceptionState.throwDOMException(
+            NotSupportedError,
+            ExceptionMessages::indexExceedsMinimumBound(
+                "phaseResponse length",
+                phaseResponse->length(),
+                frequencyHzLength));
+        return;
+    }
+
+    iirProcessor()->getFrequencyResponse(frequencyHzLength, frequencyHz->data(), magResponse->data(), phaseResponse->data());
+}
+
+} // namespace blink