Remove unnecessary members for tricky lazy initialization in AudioContext.

Source/modules/webaudio/AudioContext.cpp

 /*
  * Copyright (C) 2010, 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 92 matching lines @@
     audioContext->suspendIfNeeded();
     return audioContext.release();
 }
 
 // Constructor for rendering to the audio hardware.
 AudioContext::AudioContext(Document* document)
     : ActiveDOMObject(document)
     , m_isStopScheduled(false)
     , m_isCleared(false)
     , m_isInitialized(false)
-    , m_isAudioThreadFinished(false)
     , m_destinationNode(nullptr)
     , m_isDeletionScheduled(false)
     , m_automaticPullNodesNeedUpdating(false)
     , m_connectionCount(0)
     , m_audioThread(0)
     , m_graphOwnerThread(UndefinedThreadIdentifier)
     , m_isOfflineContext(false)
 {
+    ScriptWrappable::init(this);
+
     m_destinationNode = DefaultAudioDestinationNode::create(this);
 
-    constructCommon();
+    initialize();
 }
 
 // Constructor for offline (non-realtime) rendering.
 AudioContext::AudioContext(Document* document, unsigned numberOfChannels, size_t numberOfFrames, float sampleRate)
     : ActiveDOMObject(document)
     , m_isStopScheduled(false)
     , m_isCleared(false)
     , m_isInitialized(false)
-    , m_isAudioThreadFinished(false)
     , m_destinationNode(nullptr)
     , m_automaticPullNodesNeedUpdating(false)
     , m_connectionCount(0)
     , m_audioThread(0)
     , m_graphOwnerThread(UndefinedThreadIdentifier)
     , m_isOfflineContext(true)
 {
+    ScriptWrappable::init(this);
+
     // Create a new destination for offline rendering.
     m_renderTarget = AudioBuffer::create(numberOfChannels, numberOfFrames, sampleRate);
     if (m_renderTarget.get())
         m_destinationNode = OfflineAudioDestinationNode::create(this, m_renderTarget.get());
 
-    constructCommon();
-}
-
-void AudioContext::constructCommon()
-{
-    ScriptWrappable::init(this);
-
-    FFTFrame::initialize();
-
-    m_listener = AudioListener::create();
-
     initialize();
 }
 
 AudioContext::~AudioContext()
 {
 #if DEBUG_AUDIONODE_REFERENCES
     fprintf(stderr, "%p: AudioContext::~AudioContext()\n", this);
 #endif
     // AudioNodes keep a reference to their context, so there should be no way to be in the destructor if there are still AudioNodes around.
     ASSERT(!m_isInitialized);
     ASSERT(!m_nodesToDelete.size());
     ASSERT(!m_referencedNodes.size());
     ASSERT(!m_finishedNodes.size());
     ASSERT(!m_automaticPullNodes.size());
     if (m_automaticPullNodesNeedUpdating)
         m_renderingAutomaticPullNodes.resize(m_automaticPullNodes.size());
     ASSERT(!m_renderingAutomaticPullNodes.size());
 }
 
 void AudioContext::initialize()
 {
-    if (!m_isInitialized) {
-        // Don't allow the context to initialize a second time after it's already been explicitly uninitialized.
-        ASSERT(!m_isAudioThreadFinished);
-        if (!m_isAudioThreadFinished) {
-            // Creation of a destination node should not start the audio HW. The
-            // creation of any other AudioNode will initialize the audio HW and start processing
-            if (m_destinationNode.get()) {
-                m_destinationNode->initialize();
+    if (isInitialized())
+        return;
 
-                if (!isOfflineContext()) {
-                    // This starts the audio thread. The destination node's provideInput() method will now be called repeatedly to render audio.
-                    // Each time provideInput() is called, a portion of the audio stream is rendered. Let's call this time period a "render quantum".
-                    // NOTE: for now default AudioContext does not need an explicit startRendering() call from JavaScript.
-                    // We may want to consider requiring it for symmetry with OfflineAudioContext.
-                    m_destinationNode->startRendering();
-                    ++s_hardwareContextCount;
-                }
+    FFTFrame::initialize();
+    m_listener = AudioListener::create();
 
-                m_isInitialized = true;
-            }
+    if (m_destinationNode.get()) {
+        m_destinationNode->initialize();
+
+        if (!isOfflineContext()) {
+            // This starts the audio thread. The destination node's provideInput() method will now be called repeatedly to render audio.
+            // Each time provideInput() is called, a portion of the audio stream is rendered. Let's call this time period a "render quantum".
+            // NOTE: for now default AudioContext does not need an explicit startRendering() call from JavaScript.
+            // We may want to consider requiring it for symmetry with OfflineAudioContext.
+            m_destinationNode->startRendering();
+            ++s_hardwareContextCount;
         }
+
+        m_isInitialized = true;
     }
 }
 
 void AudioContext::clear()
 {
     // We have to release our reference to the destination node before the context will ever be deleted since the destination node holds a reference to the context.
     if (m_destinationNode)
         m_destinationNode.clear();
 
     // Audio thread is dead. Nobody will schedule node deletion action. Let's do it ourselves.
     do {
         m_nodesToDelete.appendVector(m_nodesMarkedForDeletion);
         m_nodesMarkedForDeletion.clear();
         deleteMarkedNodes();
     } while (m_nodesToDelete.size());
 
     m_isCleared = true;
 }
 
 void AudioContext::uninitialize()
 {
     ASSERT(isMainThread());
 
-    if (!m_isInitialized)
+    if (!isInitialized())
         return;
 
     // This stops the audio thread and all audio rendering.
     m_destinationNode->uninitialize();
 
-    // Don't allow the context to initialize a second time after it's already been explicitly uninitialized.
-    m_isAudioThreadFinished = true;
-
     if (!isOfflineContext()) {
         ASSERT(s_hardwareContextCount);
         --s_hardwareContextCount;
     }
 
     // Get rid of the sources which may still be playing.
     derefUnfinishedSourceNodes();
 
     m_isInitialized = false;
 }
 
-bool AudioContext::isInitialized() const
-{
-    return m_isInitialized;
-}
-
 void AudioContext::stopDispatch(void* userData)
 {
     AudioContext* context = reinterpret_cast<AudioContext*>(userData);
     ASSERT(context);
     if (!context)
         return;
 
     context->uninitialize();
     context->clear();
 }
@@ skipping 329 matching lines @@
 
 void AudioContext::notifyNodeFinishedProcessing(AudioNode* node)
 {
     ASSERT(isAudioThread());
     m_finishedNodes.append(node);
 }
 
 void AudioContext::derefFinishedSourceNodes()
 {
     ASSERT(isGraphOwner());
-    ASSERT(isAudioThread() || isAudioThreadFinished());
+    ASSERT(isAudioThread());
     for (unsigned i = 0; i < m_finishedNodes.size(); i++)
         derefNode(m_finishedNodes[i]);
 
     m_finishedNodes.clear();
 }
 
 void AudioContext::refNode(AudioNode* node)
 {
     ASSERT(isMainThread());
     AutoLocker locker(this);
@@ skipping 11 matching lines @@
     for (unsigned i = 0; i < m_referencedNodes.size(); ++i) {
         if (node == m_referencedNodes[i]) {
             m_referencedNodes.remove(i);
             break;
         }
     }
 }
 
 void AudioContext::derefUnfinishedSourceNodes()
 {
-    ASSERT(isMainThread() && isAudioThreadFinished());
+    ASSERT(isMainThread());
     for (unsigned i = 0; i < m_referencedNodes.size(); ++i)
         m_referencedNodes[i]->deref(AudioNode::RefTypeConnection);
 
     m_referencedNodes.clear();
 }
 
 void AudioContext::lock(bool& mustReleaseLock)
 {
     // Don't allow regular lock in real-time audio thread.
     ASSERT(isMainThread());
@@ skipping 10 matching lines @@
         mustReleaseLock = true;
     }
 }
 
 bool AudioContext::tryLock(bool& mustReleaseLock)
 {
     ThreadIdentifier thisThread = currentThread();
     bool isAudioThread = thisThread == audioThread();
 
     // Try to catch cases of using try lock on main thread - it should use regular lock.
-    ASSERT(isAudioThread || isAudioThreadFinished());
+    ASSERT(isAudioThread);
 
     if (!isAudioThread) {
         // In release build treat tryLock() as lock() (since above ASSERT(isAudioThread) never fires) - this is the best we can do.
         lock(mustReleaseLock);
         return true;
     }
 
     bool hasLock;
 
     if (thisThread == m_graphOwnerThread) {
@@ skipping 94 matching lines @@
         node->finishDeref(AudioNode::RefTypeConnection);
     }
 
     m_deferredFinishDerefList.clear();
 }
 
 void AudioContext::markForDeletion(AudioNode* node)
 {
     ASSERT(isGraphOwner());
 
-    if (isAudioThreadFinished())
+    if (!isInitialized())
         m_nodesToDelete.append(node);
     else
         m_nodesMarkedForDeletion.append(node);
 
     // This is probably the best time for us to remove the node from automatic pull list,
     // since all connections are gone and we hold the graph lock. Then when handlePostRenderTasks()
     // gets a chance to schedule the deletion work, updateAutomaticPullNodes() also gets a chance to
     // modify m_renderingAutomaticPullNodes.
     removeAutomaticPullNode(node);
 }
 
 void AudioContext::scheduleNodeDeletion()
 {
-    bool isGood = m_isInitialized && isGraphOwner();
+    bool isGood = isInitialized() && isGraphOwner();
     ASSERT(isGood);
     if (!isGood)
         return;
 
     // Make sure to call deleteMarkedNodes() on main thread.
     if (m_nodesMarkedForDeletion.size() && !m_isDeletionScheduled) {
         m_nodesToDelete.appendVector(m_nodesMarkedForDeletion);
         m_nodesMarkedForDeletion.clear();
 
         m_isDeletionScheduled = true;
@@ skipping 175 matching lines @@
     visitor->trace(m_renderTarget);
     visitor->trace(m_destinationNode);
     visitor->trace(m_listener);
     visitor->trace(m_dirtySummingJunctions);
     EventTargetWithInlineData::trace(visitor);
 }
 
 } // namespace WebCore
 
 #endif // ENABLE(WEB_AUDIO)