Implement tail processing for AudioNodes

third_party/WebKit/Source/modules/webaudio/DeferredTaskHandler.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 151 matching lines @@
   }
 }
 
 void DeferredTaskHandler::ProcessAutomaticPullNodes(size_t frames_to_process) {
   DCHECK(IsAudioThread());
 
   for (unsigned i = 0; i < rendering_automatic_pull_nodes_.size(); ++i)
     rendering_automatic_pull_nodes_[i]->ProcessIfNecessary(frames_to_process);
 }
 
+void DeferredTaskHandler::AddTailProcessingNode(PassRefPtr<AudioHandler> node) {
+  DCHECK(IsGraphOwner());
+
+  if (!tail_processing_nodes_.Contains(node)) {
+#if DEBUG_AUDIONODE_REFERENCES > 1
+    node->AddTailProcessingDebug();
+#endif
+    tail_processing_nodes_.push_back(std::move(node));
+  }
+}
+
+void DeferredTaskHandler::RemoveTailProcessingNode(
+    PassRefPtr<AudioHandler> node) {
+  DCHECK(IsGraphOwner());
+
+  size_t index = tail_processing_nodes_.Find(node);
+  if (index != kNotFound) {
+#if DEBUG_AUDIONODE_REFERENCES > 1
+    node->RemoveTailProcessingDebug();
+#endif
+    node->ReallyDisableOutputs();
+    tail_processing_nodes_.erase(index);
+  }
+}
+
+void DeferredTaskHandler::UpdateTailProcessingNodes() {
+  DCHECK(IsAudioThread());
+
+  for (unsigned k = tail_processing_nodes_.size(); k > 0; --k) {
+    RefPtr<AudioHandler> node = tail_processing_nodes_[k - 1];
+    if (node->PropagatesSilence()) {
+#if DEBUG_AUDIONODE_REFERENCES
+      fprintf(stderr, "[%16p]: %16p: %2d: updateTail @%.15g\n", node->Context(),
+              node.Get(), node->GetNodeType(), node->Context()->currentTime());
+#endif
+      RemoveTailProcessingNode(node);
+    }
+  }
+}
+
 void DeferredTaskHandler::AddChangedChannelCountMode(AudioHandler* node) {
   DCHECK(IsGraphOwner());
   DCHECK(IsMainThread());
   deferred_count_mode_change_.insert(node);
 }
 
 void DeferredTaskHandler::RemoveChangedChannelCountMode(AudioHandler* node) {
   DCHECK(IsGraphOwner());
 
   deferred_count_mode_change_.erase(node);
@@ skipping 41 matching lines @@
     rendering_automatic_pull_nodes_.resize(automatic_pull_nodes_.size());
   DCHECK(!rendering_automatic_pull_nodes_.size());
 }
 
 void DeferredTaskHandler::HandleDeferredTasks() {
   UpdateChangedChannelCountMode();
   UpdateChangedChannelInterpretation();
   HandleDirtyAudioSummingJunctions();
   HandleDirtyAudioNodeOutputs();
   UpdateAutomaticPullNodes();
+  UpdateTailProcessingNodes();
 }
 
 void DeferredTaskHandler::ContextWillBeDestroyed() {
   for (auto& handler : rendering_orphan_handlers_)
     handler->ClearContext();
   for (auto& handler : deletable_orphan_handlers_)
     handler->ClearContext();
   ClearHandlersToBeDeleted();
   // Some handlers might live because of their cross thread tasks.
 }
@@ skipping 42 matching lines @@
   deletable_orphan_handlers_.clear();
 }
 
 void DeferredTaskHandler::SetAudioThreadToCurrentThread() {
   DCHECK(!IsMainThread());
   ThreadIdentifier thread = CurrentThread();
   ReleaseStore(&audio_thread_, thread);
 }
 
 }  // namespace blink