AudioWorklet prototype

third_party/WebKit/Source/modules/webaudio/AudioWorkletMessagingProxy.h

 // 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.
 
 #ifndef AudioWorkletMessagingProxy_h
 #define AudioWorkletMessagingProxy_h
 
 #include <memory>
-#include "core/workers/ThreadedWorkletMessagingProxy.h"
+#include "core/CoreExport.h"
+#include "core/loader/WorkletScriptLoader.h"
+#include "core/workers/ThreadedMessagingProxyBase.h"
+#include "core/workers/WorkletGlobalScopeProxy.h"
+#include "core/workers/WorkletPendingTasks.h"
+#include "platform/wtf/WeakPtr.h"
 
 namespace blink {
 
-class ExecutionContext;
-class WorkerThread;
+class AudioWorkletHandler;
+class AudioWorkletObjectProxy;
+class ScriptSourceCode;
+class WaitableEvent;
+class WebThreadSupportingGC;
 
-class AudioWorkletMessagingProxy final : public ThreadedWorkletMessagingProxy {
+// NOTE: Currently this class is a duplication of ThreadedWorkletMessagingProxy,
+// because it needs to have the ownership of the worker thread.
+// 
+// When rebasing the code, make sure to copy the behavior of
+// |ThreadedWorkletMessagingProxy| instead of inheriting from it. Think of this
+// class is a composition of |ThreadedWorkletMessagingProxy| and
+// |AudioWorkletMessagingProxy|. This is because we need a direct access of
+// |worklet_object_proxy| from BaseAudioContext.
+
+class CORE_EXPORT AudioWorkletMessagingProxy
+    : public ThreadedMessagingProxyBase,
+      public WorkletGlobalScopeProxy {
+  USING_GARBAGE_COLLECTED_MIXIN(AudioWorkletMessagingProxy);
+
  public:
   AudioWorkletMessagingProxy(ExecutionContext*, WorkerClients*);
 
+  // WorkletGlobalScopeProxy implementation.
+  void FetchAndInvokeScript(const KURL& module_url_record,
+                            WebURLRequest::FetchCredentialsMode,
+                            RefPtr<WebTaskRunner> outside_settings_task_runner,
+                            WorkletPendingTasks*) final;
+  void WorkletObjectDestroyed() final;
+  void TerminateWorkletGlobalScope() final;
+
+  void Initialize();
+
+  DECLARE_VIRTUAL_TRACE();
+
+  // This blocks the main thread until the rendering thread completes the
+  // creation of AudioWorkletProcessor.
+  void CreateProcessorInstance(const String& name,
+                               AudioWorkletHandler*,
+                               WaitableEvent*);
+
+  // This returns the rendering thread so it can be passed to AudioDestination.
+  WebThreadSupportingGC* GetRenderingThread();
+
+ protected:
+  std::unique_ptr<WorkerThread> CreateWorkerThread(double origin_time) override;
+
+  AudioWorkletObjectProxy& WorkletObjectProxy() {
+    return *worklet_object_proxy_;
+  }
+
  private:
-  ~AudioWorkletMessagingProxy() override;
+  friend class AudioWorkletMessagingProxyForTest;
+  class LoaderClient;
 
-  std::unique_ptr<WorkerThread> CreateWorkerThread(double origin_time) override;
+  void NotifyLoadingFinished(WorkletScriptLoader*);
+  void EvaluateScript(const ScriptSourceCode&);
+
+  std::unique_ptr<AudioWorkletObjectProxy> worklet_object_proxy_;
+  HeapHashSet<Member<WorkletScriptLoader>> loaders_;
 };
 
 }  // namespace blink
 
 #endif  // AudioWorkletMessagingProxy_h