Split "Online" and "Offline" AudioContext processing

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 39 matching lines @@
 #include "modules/webaudio/DefaultAudioDestinationNode.h"
 #include "modules/webaudio/DelayNode.h"
 #include "modules/webaudio/DynamicsCompressorNode.h"
 #include "modules/webaudio/GainNode.h"
 #include "modules/webaudio/MediaElementAudioSourceNode.h"
 #include "modules/webaudio/MediaStreamAudioDestinationNode.h"
 #include "modules/webaudio/MediaStreamAudioSourceNode.h"
 #include "modules/webaudio/OfflineAudioCompletionEvent.h"
 #include "modules/webaudio/OfflineAudioContext.h"
 #include "modules/webaudio/OfflineAudioDestinationNode.h"
+#include "modules/webaudio/OnlineAudioContext.h"
 #include "modules/webaudio/OscillatorNode.h"
 #include "modules/webaudio/PannerNode.h"
 #include "modules/webaudio/PeriodicWave.h"
 #include "modules/webaudio/ScriptProcessorNode.h"
 #include "modules/webaudio/StereoPannerNode.h"
 #include "modules/webaudio/WaveShaperNode.h"
 #include "platform/ThreadSafeFunctional.h"
 #include "public/platform/Platform.h"
 #include "wtf/text/WTFString.h"
 
-#if DEBUG_AUDIONODE_REFERENCES
-#include <stdio.h>
-#endif
-
 namespace blink {
 
-// Don't allow more than this number of simultaneous AudioContexts talking to hardware.
-const unsigned MaxHardwareContexts = 6;
-unsigned AudioContext::s_hardwareContextCount = 0;
-unsigned AudioContext::s_contextId = 0;
-
 AudioContext* AudioContext::create(Document& document, ExceptionState& exceptionState)
 {
-    ASSERT(isMainThread());
-    if (s_hardwareContextCount >= MaxHardwareContexts) {
-        exceptionState.throwDOMException(
-            NotSupportedError,
-            ExceptionMessages::indexExceedsMaximumBound(
-                "number of hardware contexts",
-                s_hardwareContextCount,
-                MaxHardwareContexts));
-        return nullptr;
-    }
+    return OnlineAudioContext::create(document, exceptionState);
+}
 
-    AudioContext* audioContext = new AudioContext(&document);
-    audioContext->suspendIfNeeded();
-    return audioContext;
-}
+// FIXME(dominicc): Devolve these constructors to OnlineAudioContext
+// and OfflineAudioContext respectively.
 
 // Constructor for rendering to the audio hardware.
 AudioContext::AudioContext(Document* document)
     : ActiveDOMObject(document)
     , m_isStopScheduled(false)
     , m_isCleared(false)
     , m_isInitialized(false)
     , m_destinationNode(nullptr)
     , m_isResolvingResumePromises(false)
     , m_connectionCount(0)
     , m_didInitializeContextGraphMutex(false)
     , m_deferredTaskHandler(DeferredTaskHandler::create())
-    , m_isOfflineContext(false)
     , m_contextState(Suspended)
 {
     m_didInitializeContextGraphMutex = true;
     m_destinationNode = DefaultAudioDestinationNode::create(this);
 
     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_destinationNode(nullptr)
     , m_isResolvingResumePromises(false)
     , m_connectionCount(0)
     , m_didInitializeContextGraphMutex(false)
     , m_deferredTaskHandler(DeferredTaskHandler::create())
-    , m_isOfflineContext(true)
     , m_contextState(Suspended)
 {
     m_didInitializeContextGraphMutex = true;
     // 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());
 
     initialize();
 }
 
 AudioContext::~AudioContext()
 {
-#if DEBUG_AUDIONODE_REFERENCES
-    fprintf(stderr, "%p: AudioContext::~AudioContext(): %u\n", this, m_contextId);
-#endif
     deferredTaskHandler().contextWillBeDestroyed();
     // 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_activeSourceNodes.size());
     ASSERT(!m_finishedSourceHandlers.size());
     ASSERT(!m_isResolvingResumePromises);
     ASSERT(!m_resumeResolvers.size());
 }
 
 void AudioContext::initialize()
 {
     if (isInitialized())
         return;
 
     FFTFrame::initialize();
     m_listener = AudioListener::create();
 
     if (m_destinationNode.get()) {
         m_destinationNode->handler().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.
-            startRendering();
-            ++s_hardwareContextCount;
-        }
-
-        m_contextId = s_contextId++;
         m_isInitialized = true;
-#if DEBUG_AUDIONODE_REFERENCES
-        fprintf(stderr, "%p: AudioContext::AudioContext(): %u #%u\n",
-            this, m_contextId, AudioContext::s_hardwareContextCount);
-#endif
     }
 }
 
 void AudioContext::clear()
 {
     m_destinationNode.clear();
     // The audio rendering thread is dead.  Nobody will schedule AudioHandler
     // deletion.  Let's do it ourselves.
     deferredTaskHandler().clearHandlersToBeDeleted();
     m_isCleared = true;
 }
 
 void AudioContext::uninitialize()
 {
     ASSERT(isMainThread());
 
     if (!isInitialized())
         return;
 
     m_isInitialized = false;
 
     // This stops the audio thread and all audio rendering.
     if (m_destinationNode)
         m_destinationNode->handler().uninitialize();
 
-    if (!isOfflineContext()) {
-        ASSERT(s_hardwareContextCount);
-        --s_hardwareContextCount;
-    }
-
     // Get rid of the sources which may still be playing.
     releaseActiveSourceNodes();
 
     // Reject any pending resolvers before we go away.
     rejectPendingResolvers();
-
-    // For an offline audio context, the completion event will set the state to closed.  For an
-    // online context, we need to do it here.  We only want to set the closed state once.
-    if (!isOfflineContext())
-        setContextState(Closed);
-
-    // Resolve the promise now, if any
-    if (m_closeResolver)
-        m_closeResolver->resolve();
+    didClose();
 
     ASSERT(m_listener);
     m_listener->waitForHRTFDatabaseLoaderThreadCompletion();
 
     clear();
 }
 
 void AudioContext::stop()
 {
     // Usually ExecutionContext calls stop twice.
@@ skipping 484 matching lines @@
     // Notify context that state changed
     if (executionContext())
         executionContext()->postTask(FROM_HERE, createSameThreadTask(&AudioContext::notifyStateChange, this));
 }
 
 void AudioContext::notifyStateChange()
 {
     dispatchEvent(Event::create(EventTypeNames::statechange));
 }
 
-ScriptPromise AudioContext::suspendContext(ScriptState* scriptState)
-{
-    ASSERT(isMainThread());
-    AutoLocker locker(this);
-
-    if (isOfflineContext()) {
-        return ScriptPromise::rejectWithDOMException(
-            scriptState,
-            DOMException::create(
-                InvalidAccessError,
-                "cannot suspend an OfflineAudioContext"));
-    }
-
-    RefPtrWillBeRawPtr<ScriptPromiseResolver> resolver = ScriptPromiseResolver::create(scriptState);
-    ScriptPromise promise = resolver->promise();
-
-    if (m_contextState == Closed) {
-        resolver->reject(
-            DOMException::create(InvalidStateError, "Cannot suspend a context that has been closed"));
-    } else {
-        // Stop rendering now.
-        if (m_destinationNode)
-            stopRendering();
-
-        // Since we don't have any way of knowing when the hardware actually stops, we'll just
-        // resolve the promise now.
-        resolver->resolve();
-    }
-
-    return promise;
-}
-
-ScriptPromise AudioContext::resumeContext(ScriptState* scriptState)
-{
-    ASSERT(isMainThread());
-    AutoLocker locker(this);
-
-    if (isOfflineContext()) {
-        return ScriptPromise::rejectWithDOMException(
-            scriptState,
-            DOMException::create(
-                InvalidAccessError,
-                "cannot resume an OfflineAudioContext"));
-    }
-
-    if (isContextClosed()) {
-        return ScriptPromise::rejectWithDOMException(
-            scriptState,
-            DOMException::create(
-                InvalidAccessError,
-                "cannot resume a closed AudioContext"));
-    }
-
-    RefPtrWillBeRawPtr<ScriptPromiseResolver> resolver = ScriptPromiseResolver::create(scriptState);
-    ScriptPromise promise = resolver->promise();
-
-    // Restart the destination node to pull on the audio graph.
-    if (m_destinationNode)
-        startRendering();
-
-    // Save the resolver which will get resolved when the destination node starts pulling on the
-    // graph again.
-    m_resumeResolvers.append(resolver);
-
-    return promise;
-}
-
 void AudioContext::notifySourceNodeFinishedProcessing(AudioHandler* handler)
 {
     ASSERT(isAudioThread());
     m_finishedSourceHandlers.append(handler);
 }
 
 void AudioContext::releaseFinishedSourceNodes()
 {
     ASSERT(isGraphOwner());
     ASSERT(isAudioThread());
@@ skipping 141 matching lines @@
     // This is called for both online and offline contexts.
     ASSERT(isMainThread());
     ASSERT(m_destinationNode);
 
     if (m_contextState == Suspended) {
         destination()->audioDestinationHandler().startRendering();
         setContextState(Running);
     }
 }
 
-void AudioContext::stopRendering()
-{
-    ASSERT(isMainThread());
-    ASSERT(m_destinationNode);
-    ASSERT(!isOfflineContext());
-
-    if (m_contextState == Running) {
-        destination()->audioDestinationHandler().stopRendering();
-        setContextState(Suspended);
-        deferredTaskHandler().clearHandlersToBeDeleted();
-    }
-}
-
 void AudioContext::fireCompletionEvent()
 {
     ASSERT(isMainThread());
     if (!isMainThread())
         return;
 
     AudioBuffer* renderedBuffer = m_renderTarget.get();
 
     // For an offline context, we set the state to closed here so that the oncomplete handler sees
     // that the context has been closed.
     setContextState(Closed);
 
     ASSERT(renderedBuffer);
     if (!renderedBuffer)
         return;
 
     // Avoid firing the event if the document has already gone away.
     if (executionContext()) {
         // Call the offline rendering completion event listener and resolve the promise too.
         dispatchEvent(OfflineAudioCompletionEvent::create(renderedBuffer));
         m_offlineResolver->resolve(renderedBuffer);
     }
 }
 
 DEFINE_TRACE(AudioContext)
 {
-    visitor->trace(m_closeResolver);
     visitor->trace(m_offlineResolver);
     visitor->trace(m_renderTarget);
     visitor->trace(m_destinationNode);
     visitor->trace(m_listener);
     // trace() can be called in AudioContext constructor, and
     // m_contextGraphMutex might be unavailable.
     if (m_didInitializeContextGraphMutex) {
         AutoLocker lock(this);
         visitor->trace(m_activeSourceNodes);
     } else {
         visitor->trace(m_activeSourceNodes);
     }
     visitor->trace(m_resumeResolvers);
     RefCountedGarbageCollectedEventTargetWithInlineData<AudioContext>::trace(visitor);
     ActiveDOMObject::trace(visitor);
 }
 
 SecurityOrigin* AudioContext::securityOrigin() const
 {
     if (executionContext())
         return executionContext()->securityOrigin();
 
     return nullptr;
 }
 
-ScriptPromise AudioContext::closeContext(ScriptState* scriptState)
-{
-    if (isOfflineContext()) {
-        return ScriptPromise::rejectWithDOMException(
-            scriptState,
-            DOMException::create(InvalidAccessError, "cannot close an OfflineAudioContext."));
-    }
-
-    if (isContextClosed()) {
-        // We've already closed the context previously, but it hasn't yet been resolved, so just
-        // create a new promise and reject it.
-        return ScriptPromise::rejectWithDOMException(
-            scriptState,
-            DOMException::create(InvalidStateError,
-                "Cannot close a context that is being closed or has already been closed."));
-    }
-
-    m_closeResolver = ScriptPromiseResolver::create(scriptState);
-    ScriptPromise promise = m_closeResolver->promise();
-
-    // Stop the audio context. This will stop the destination node from pulling audio anymore. And
-    // since we have disconnected the destination from the audio graph, and thus has no references,
-    // the destination node can GCed if JS has no references. stop() will also resolve the Promise
-    // created here.
-    stop();
-
-    return promise;
-}
-
 } // namespace blink
 
 #endif // ENABLE(WEB_AUDIO)