Add constructor for MediaStreamAudioDestinationNode

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

 /*
  * Copyright (C) 2012, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1.  Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 10 matching lines @@
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
  * DAMAGE.
  */
 
 #include "modules/webaudio/MediaStreamAudioDestinationNode.h"
 #include "bindings/core/v8/ExceptionMessages.h"
 #include "bindings/core/v8/ExceptionState.h"
 #include "core/dom/ExceptionCode.h"
 #include "modules/webaudio/AudioNodeInput.h"
+#include "modules/webaudio/AudioNodeOptions.h"
 #include "modules/webaudio/BaseAudioContext.h"
 #include "platform/UUID.h"
 #include "platform/mediastream/MediaStreamCenter.h"
 #include "public/platform/WebRTCPeerConnectionHandler.h"
 #include "wtf/Locker.h"
 
 namespace blink {
 
 // WebAudioCapturerSource ignores the channel count beyond 8, so we set the
 // block here to avoid anything can cause the crash.
@@ skipping 67 matching lines @@
 
 void MediaStreamAudioDestinationHandler::setChannelCount(
     unsigned long channelCount,
     ExceptionState& exceptionState) {
   DCHECK(isMainThread());
 
   // Currently the maximum channel count supported for this node is 8,
   // which is constrained by m_source (WebAudioCapturereSource). Although
   // it has its own safety check for the excessive channels, throwing an
   // exception here is useful to developers.
-  if (channelCount > maxChannelCount()) {
+  if (channelCount < 1 || channelCount > maxChannelCount()) {
     exceptionState.throwDOMException(
-        IndexSizeError,
+        NotSupportedError,
         ExceptionMessages::indexOutsideRange<unsigned>(
             "channel count", channelCount, 1, ExceptionMessages::InclusiveBound,
             maxChannelCount(), ExceptionMessages::InclusiveBound));
     return;
   }
 
   // Synchronize changes in the channel count with process() which
   // needs to update m_mixBus.
   MutexLocker locker(m_processLock);
 
@@ skipping 21 matching lines @@
   DCHECK(isMainThread());
 
   if (context.isContextClosed()) {
     context.throwExceptionForClosedState(exceptionState);
     return nullptr;
   }
 
   return new MediaStreamAudioDestinationNode(context, numberOfChannels);
 }
 
+MediaStreamAudioDestinationNode* MediaStreamAudioDestinationNode::create(
+    BaseAudioContext* context,
+    const AudioNodeOptions& options,
+    ExceptionState& exceptionState) {
+  DCHECK(isMainThread());
+
+  // Default to stereo; |options| will update it approriately if needed.
+  MediaStreamAudioDestinationNode* node =
+      new MediaStreamAudioDestinationNode(*context, 2);
+
+  if (!node)

[tkent, 2016/12/19 23:35:01]

|new| operator never returns nullptr. This check is unnecessary.

+    return nullptr;
+
+  // Need to handle channelCount here ourselves because the upper
+  // limit is different from the normal AudioNode::setChannelCount
+  // limit of 32.  Error messages will sometimes show the wrong
+  // limits.
+  if (options.hasChannelCount())
+    node->setChannelCount(options.channelCount(), exceptionState);
+
+  node->handleChannelOptions(options, exceptionState);
+
+  return node;
+}
+
 MediaStream* MediaStreamAudioDestinationNode::stream() const {
   return static_cast<MediaStreamAudioDestinationHandler&>(handler()).stream();
 }
 
 }  // namespace blink