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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-*/
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef MOZILLA_MEDIATRACKGRAPHIMPL_H_
#define MOZILLA_MEDIATRACKGRAPHIMPL_H_
#include "MediaTrackGraph.h"
#include "AudioMixer.h"
#include "GraphDriver.h"
#include "mozilla/Atomics.h"
#include "mozilla/Monitor.h"
#include "mozilla/TimeStamp.h"
#include "mozilla/UniquePtr.h"
#include "mozilla/WeakPtr.h"
#include "nsClassHashtable.h"
#include "nsIMemoryReporter.h"
#include "nsINamed.h"
#include "nsIRunnable.h"
#include "nsIThreadInternal.h"
#include "nsITimer.h"
#include "AsyncLogger.h"
namespace mozilla {
namespace media {
class ShutdownBlocker;
}
class AudioContextOperationControlMessage;
template <typename T>
class LinkedList;
class GraphRunner;
/**
* A per-track update message passed from the media graph thread to the
* main thread.
*/
struct TrackUpdate {
RefPtr<MediaTrack> mTrack;
TrackTime mNextMainThreadCurrentTime;
bool mNextMainThreadEnded;
};
/**
* This represents a message run on the graph thread to modify track or graph
* state. These are passed from main thread to graph thread through
* AppendMessage(), or scheduled on the graph thread with
* RunMessageAfterProcessing(). A ControlMessage
* always has a weak reference to a particular affected track.
*/
class ControlMessage {
public:
explicit ControlMessage(MediaTrack* aTrack) : mTrack(aTrack) {
MOZ_COUNT_CTOR(ControlMessage);
}
// All these run on the graph thread
MOZ_COUNTED_DTOR_VIRTUAL(ControlMessage)
// Do the action of this message on the MediaTrackGraph thread. Any actions
// affecting graph processing should take effect at mProcessedTime.
// All track data for times < mProcessedTime has already been
// computed.
virtual void Run() = 0;
// RunDuringShutdown() is only relevant to messages generated on the main
// thread (for AppendMessage()).
// When we're shutting down the application, most messages are ignored but
// some cleanup messages should still be processed (on the main thread).
// This must not add new control messages to the graph.
virtual void RunDuringShutdown() {}
MediaTrack* GetTrack() { return mTrack; }
protected:
// We do not hold a reference to mTrack. The graph will be holding a reference
// to the track until the Destroy message is processed. The last message
// referencing a track is the Destroy message for that track.
MediaTrack* mTrack;
};
class MessageBlock {
public:
nsTArray<UniquePtr<ControlMessage>> mMessages;
};
/**
* The implementation of a media track graph. This class is private to this
* file. It's not in the anonymous namespace because MediaTrack needs to
* be able to friend it.
*
* There can be multiple MediaTrackGraph per process: one per document.
* Additionaly, each OfflineAudioContext object creates its own MediaTrackGraph
* object too.
*/
class MediaTrackGraphImpl : public MediaTrackGraph,
public GraphInterface,
public nsIMemoryReporter,
public nsIThreadObserver,
public nsITimerCallback,
public nsINamed {
public:
NS_DECL_THREADSAFE_ISUPPORTS
NS_DECL_NSIMEMORYREPORTER
NS_DECL_NSITHREADOBSERVER
NS_DECL_NSITIMERCALLBACK
NS_DECL_NSINAMED
/**
* Use aGraphDriverRequested with SYSTEM_THREAD_DRIVER or AUDIO_THREAD_DRIVER
* to create a MediaTrackGraph which provides support for real-time audio
* and/or video. Set it to OFFLINE_THREAD_DRIVER in order to create a
* non-realtime instance which just churns through its inputs and produces
* output. Those objects currently only support audio, and are used to
* implement OfflineAudioContext. They do not support MediaTrack inputs.
*/
explicit MediaTrackGraphImpl(GraphDriverType aGraphDriverRequested,
GraphRunType aRunTypeRequested,
TrackRate aSampleRate, uint32_t aChannelCount,
CubebUtils::AudioDeviceID aOutputDeviceID,
AbstractThread* aWindow);
// Intended only for assertions, either on graph thread or not running (in
// which case we must be on the main thread).
bool OnGraphThreadOrNotRunning() const override;
bool OnGraphThread() const override;
bool Destroyed() const override;
#ifdef DEBUG
/**
* True if we're on aDriver's thread, or if we're on mGraphRunner's thread
* and mGraphRunner is currently run by aDriver.
*/
bool InDriverIteration(GraphDriver* aDriver) override;
#endif
/**
* Unregisters memory reporting and deletes this instance. This should be
* called instead of calling the destructor directly.
*/
void Destroy();
// Main thread only.
/**
* This runs every time we need to sync state from the media graph thread
* to the main thread while the main thread is not in the middle
* of a script. It runs during a "stable state" (per HTML5) or during
* an event posted to the main thread.
* The boolean affects which boolean controlling runnable dispatch is cleared
*/
void RunInStableState(bool aSourceIsMTG);
/**
* Ensure a runnable to run RunInStableState is posted to the appshell to
* run at the next stable state (per HTML5).
* See EnsureStableStateEventPosted.
*/
void EnsureRunInStableState();
/**
* Called to apply a TrackUpdate to its track.
*/
void ApplyTrackUpdate(TrackUpdate* aUpdate);
/**
* Append a ControlMessage to the message queue. This queue is drained
* during RunInStableState; the messages will run on the graph thread.
*/
void AppendMessage(UniquePtr<ControlMessage> aMessage);
/**
* Dispatches a runnable from any thread to the correct main thread for this
* MediaTrackGraph.
*/
void Dispatch(already_AddRefed<nsIRunnable>&& aRunnable);
/**
* Make this MediaTrackGraph enter forced-shutdown state. This state
* will be noticed by the media graph thread, which will shut down all tracks
* and other state controlled by the media graph thread.
* This is called during application shutdown, and on document unload if an
* AudioContext is using the graph.
*/
void ForceShutDown();
/**
* Sets mShutdownBlocker and makes it block shutdown.
* Main thread only. Not idempotent.
*/
void AddShutdownBlocker();
/**
* Removes mShutdownBlocker and unblocks shutdown.
* Main thread only. Idempotent.
*/
void RemoveShutdownBlocker();
/**
* Called before the thread runs.
*/
void Init();
/**
* Respond to CollectReports with sizes collected on the graph thread.
*/
static void FinishCollectReports(
nsIHandleReportCallback* aHandleReport, nsISupports* aData,
const nsTArray<AudioNodeSizes>& aAudioTrackSizes);
// The following methods run on the graph thread (or possibly the main thread
// if mLifecycleState > LIFECYCLE_RUNNING)
void CollectSizesForMemoryReport(
already_AddRefed<nsIHandleReportCallback> aHandleReport,
already_AddRefed<nsISupports> aHandlerData);
/**
* Returns true if this MediaTrackGraph should keep running
*/
bool UpdateMainThreadState();
/**
* Proxy method called by GraphDriver to iterate the graph.
* If this graph was created with GraphRunType SINGLE_THREAD, mGraphRunner
* will take care of calling OneIterationImpl from its thread. Otherwise,
* OneIterationImpl is called directly. Output from the graph gets mixed into
* aMixer, if it is non-null.
*/
IterationResult OneIteration(GraphTime aStateEnd, GraphTime aIterationEnd,
AudioMixer* aMixer) override;
/**
* Returns true if this MediaTrackGraph should keep running
*/
IterationResult OneIterationImpl(GraphTime aStateEnd, GraphTime aIterationEnd,
AudioMixer* aMixer);
/**
* Called from the driver, when the graph thread is about to stop, to tell
* the main thread to attempt to begin cleanup. The main thread may either
* shutdown or revive the graph depending on whether it receives new
* messages.
*/
void SignalMainThreadCleanup();
/* This is the end of the current iteration, that is, the current time of the
* graph. */
GraphTime IterationEnd() const;
/**
* Ensure there is an event posted to the main thread to run RunInStableState.
* mMonitor must be held.
* See EnsureRunInStableState
*/
void EnsureStableStateEventPosted();
/**
* Generate messages to the main thread to update it for all state changes.
* mMonitor must be held.
*/
void PrepareUpdatesToMainThreadState(bool aFinalUpdate);
/**
* If we are rendering in non-realtime mode, we don't want to send messages to
* the main thread at each iteration for performance reasons. We instead
* notify the main thread at the same rate
*/
bool ShouldUpdateMainThread();
// The following methods are the various stages of RunThread processing.
/**
* Advance all track state to mStateComputedTime.
*/
void UpdateCurrentTimeForTracks(GraphTime aPrevCurrentTime);
/**
* Process chunks for all tracks and raise events for properties that have
* changed, such as principalId.
*/
void ProcessChunkMetadata(GraphTime aPrevCurrentTime);
/**
* Process chunks for the given track and interval, and raise events for
* properties that have changed, such as principalHandle.
*/
template <typename C, typename Chunk>
void ProcessChunkMetadataForInterval(MediaTrack* aTrack, C& aSegment,
TrackTime aStart, TrackTime aEnd);
/**
* Process graph messages in mFrontMessageQueue.
*/
void RunMessagesInQueue();
/**
* Update track processing order and recompute track blocking until
* aEndBlockingDecisions.
*/
void UpdateGraph(GraphTime aEndBlockingDecisions);
void SwapMessageQueues() {
MOZ_ASSERT(OnGraphThreadOrNotRunning());
mMonitor.AssertCurrentThreadOwns();
MOZ_ASSERT(mFrontMessageQueue.IsEmpty());
mFrontMessageQueue.SwapElements(mBackMessageQueue);
if (!mFrontMessageQueue.IsEmpty()) {
EnsureNextIteration();
}
}
/**
* Do all the processing and play the audio and video, from
* mProcessedTime to mStateComputedTime.
*/
void Process(AudioMixer* aMixer);
/**
* For use during ProcessedMediaTrack::ProcessInput() or
* MediaTrackListener callbacks, when graph state cannot be changed.
* Schedules |aMessage| to run after processing, at a time when graph state
* can be changed. Graph thread.
*/
void RunMessageAfterProcessing(UniquePtr<ControlMessage> aMessage);
/**
* Resolve the GraphStartedPromise when the driver has started processing on
* the audio thread after the device has started.
*/
void NotifyWhenGraphStarted(RefPtr<MediaTrack> aTrack,
MozPromiseHolder<GraphStartedPromise>&& aHolder);
/**
* Apply an AudioContext operation (suspend/resume/close), on the graph
* thread.
*/
void ApplyAudioContextOperationImpl(
AudioContextOperationControlMessage* aMessage);
/**
* Determine if we have any audio tracks, or are about to add any audiotracks.
*/
bool AudioTrackPresent();
/**
* Schedules a replacement GraphDriver in mNextDriver, if necessary.
*/
void CheckDriver();
/**
* Sort mTracks so that every track not in a cycle is after any tracks
* it depends on, and every track in a cycle is marked as being in a cycle.
*/
void UpdateTrackOrder();
/**
* Returns smallest value of t such that t is a multiple of
* WEBAUDIO_BLOCK_SIZE and t >= aTime.
*/
static GraphTime RoundUpToEndOfAudioBlock(GraphTime aTime);
/**
* Returns smallest value of t such that t is a multiple of
* WEBAUDIO_BLOCK_SIZE and t > aTime.
*/
static GraphTime RoundUpToNextAudioBlock(GraphTime aTime);
/**
* Produce data for all tracks >= aTrackIndex for the current time interval.
* Advances block by block, each iteration producing data for all tracks
* for a single block.
* This is called whenever we have an AudioNodeTrack in the graph.
*/
void ProduceDataForTracksBlockByBlock(uint32_t aTrackIndex,
TrackRate aSampleRate);
/**
* If aTrack will underrun between aTime, and aEndBlockingDecisions, returns
* the time at which the underrun will start. Otherwise return
* aEndBlockingDecisions.
*/
GraphTime WillUnderrun(MediaTrack* aTrack, GraphTime aEndBlockingDecisions);
/**
* Given a graph time aTime, convert it to a track time taking into
* account the time during which aTrack is scheduled to be blocked.
*/
TrackTime GraphTimeToTrackTimeWithBlocking(const MediaTrack* aTrack,
GraphTime aTime) const;
/**
* If aTrack needs an audio track but doesn't have one, create it.
* If aTrack doesn't need an audio track but has one, destroy it.
*/
void CreateOrDestroyAudioTracks(MediaTrack* aTrack);
/**
* Queue audio (mix of track audio and silence for blocked intervals)
* to the audio output track. Returns the number of frames played.
*/
struct TrackKeyAndVolume {
MediaTrack* mTrack;
void* mKey;
float mVolume;
};
TrackTime PlayAudio(AudioMixer* aMixer, const TrackKeyAndVolume& aTkv,
GraphTime aPlayedTime);
/* Runs off a message on the graph thread when something requests audio from
* an input audio device of ID aID, and delivers the input audio frames to
* aListener. */
void OpenAudioInputImpl(CubebUtils::AudioDeviceID aID,
AudioDataListener* aListener);
/* Called on the main thread when something requests audio from an input
* audio device aID. */
virtual nsresult OpenAudioInput(CubebUtils::AudioDeviceID aID,
AudioDataListener* aListener) override;
/* Runs off a message on the graph when input audio from aID is not needed
* anymore, for a particular track. It can be that other tracks still need
* audio from this audio input device. */
void CloseAudioInputImpl(Maybe<CubebUtils::AudioDeviceID>& aID,
AudioDataListener* aListener);
/* Called on the main thread when input audio from aID is not needed
* anymore, for a particular track. It can be that other tracks still need
* audio from this audio input device. */
virtual void CloseAudioInput(Maybe<CubebUtils::AudioDeviceID>& aID,
AudioDataListener* aListener) override;
/* Add or remove an audio output for this track. All tracks that have an
* audio output are mixed and written to a single audio output stream. */
void RegisterAudioOutput(MediaTrack* aTrack, void* aKey);
void UnregisterAudioOutput(MediaTrack* aTrack, void* aKey);
void UnregisterAllAudioOutputs(MediaTrack* aTrack);
void SetAudioOutputVolume(MediaTrack* aTrack, void* aKey, float aVolume);
/* Called on the graph thread when the input device settings should be
* reevaluated, for example, if the channel count of the input track should
* be changed. */
void ReevaluateInputDevice();
/* Called on the graph thread when there is new output data for listeners.
* This is the mixed audio output of this MediaTrackGraph. */
void NotifyOutputData(AudioDataValue* aBuffer, size_t aFrames,
TrackRate aRate, uint32_t aChannels) override;
/* Called on the graph thread before the first Notify*Data after an
* AudioCallbackDriver starts. */
void NotifyStarted() override;
/* Called on the audio callback thread when there is new input data for
* listeners. This is the raw audio input for this MediaTrackGraph. Actual
* processing happens in ProcessInputData */
void NotifyInputData(const AudioDataValue* aBuffer, size_t aFrames,
TrackRate aRate, uint32_t aChannels) override;
/* Called on the graph thread to process the input data delivered in each
* iteration by NotifyInputData. */
void ProcessInputData();
/* Called every time there are changes to input/output audio devices like
* plug/unplug etc. This can be called on any thread, and posts a message to
* the main thread so that it can post a message to the graph thread. */
void DeviceChanged() override;
/* Called every time there are changes to input/output audio devices. This is
* called on the graph thread. */
void DeviceChangedImpl();
/**
* Compute how much track data we would like to buffer for aTrack.
*/
TrackTime GetDesiredBufferEnd(MediaTrack* aTrack);
/**
* Returns true when there are no active tracks.
*/
bool IsEmpty() const {
MOZ_ASSERT(
OnGraphThreadOrNotRunning() ||
(NS_IsMainThread() &&
LifecycleStateRef() >= LIFECYCLE_WAITING_FOR_MAIN_THREAD_CLEANUP));
return mTracks.IsEmpty() && mSuspendedTracks.IsEmpty() && mPortCount == 0;
}
/**
* Add aTrack to the graph and initializes its graph-specific state.
*/
void AddTrackGraphThread(MediaTrack* aTrack);
/**
* Remove aTrack from the graph. Ensures that pending messages about the
* track back to the main thread are flushed.
*/
void RemoveTrackGraphThread(MediaTrack* aTrack);
/**
* Remove a track from the graph. Main thread.
*/
void RemoveTrack(MediaTrack* aTrack);
/**
* Remove aPort from the graph and release it.
*/
void DestroyPort(MediaInputPort* aPort);
/**
* Mark the media track order as dirty.
*/
void SetTrackOrderDirty() {
MOZ_ASSERT(OnGraphThreadOrNotRunning());
mTrackOrderDirty = true;
}
// Get the current maximum channel count. Graph thread only.
uint32_t AudioOutputChannelCount() const;
// Set a new maximum channel count. Graph thread only.
void SetMaxOutputChannelCount(uint32_t aMaxChannelCount);
double AudioOutputLatency();
/**
* The audio input channel count for a MediaTrackGraph is the max of all the
* channel counts requested by the listeners. The max channel count is
* delivered to the listeners themselves, and they take care of downmixing.
*/
uint32_t AudioInputChannelCount() {
MOZ_ASSERT(OnGraphThreadOrNotRunning());
#ifdef ANDROID
if (!mInputDeviceUsers.GetValue(mInputDeviceID)) {
return 0;
}
#else
if (!mInputDeviceID) {
MOZ_ASSERT(mInputDeviceUsers.Count() == 0,
"If running on a platform other than android,"
"an explicit device id should be present");
return 0;
}
#endif
uint32_t maxInputChannels = 0;
// When/if we decide to support multiple input device per graph, this needs
// loop over them.
nsTArray<RefPtr<AudioDataListener>>* listeners =
mInputDeviceUsers.GetValue(mInputDeviceID);
MOZ_ASSERT(listeners);
for (const auto& listener : *listeners) {
maxInputChannels = std::max(maxInputChannels,
listener->RequestedInputChannelCount(this));
}
return maxInputChannels;
}
AudioInputType AudioInputDevicePreference() {
MOZ_ASSERT(OnGraphThreadOrNotRunning());
if (!mInputDeviceUsers.GetValue(mInputDeviceID)) {
return AudioInputType::Unknown;
}
bool voiceInput = false;
// When/if we decide to support multiple input device per graph, this needs
// loop over them.
nsTArray<RefPtr<AudioDataListener>>* listeners =
mInputDeviceUsers.GetValue(mInputDeviceID);
MOZ_ASSERT(listeners);
// If at least one track is considered to be voice,
for (const auto& listener : *listeners) {
voiceInput |= listener->IsVoiceInput(this);
}
if (voiceInput) {
return AudioInputType::Voice;
}
return AudioInputType::Unknown;
}
CubebUtils::AudioDeviceID InputDeviceID() { return mInputDeviceID; }
double MediaTimeToSeconds(GraphTime aTime) const {
NS_ASSERTION(aTime > -TRACK_TIME_MAX && aTime <= TRACK_TIME_MAX,
"Bad time");
return static_cast<double>(aTime) / GraphRate();
}
/**
* Signal to the graph that the thread has paused indefinitly,
* or resumed.
*/
void PausedIndefinitly();
void ResumedFromPaused();
/**
* Not safe to call off the MediaTrackGraph thread unless monitor is held!
*/
GraphDriver* CurrentDriver() const {
#ifdef DEBUG
if (!OnGraphThreadOrNotRunning()) {
mMonitor.AssertCurrentThreadOwns();
}
#endif
return mDriver;
}
/**
* Effectively set the new driver, while we are switching.
* It is only safe to call this at the very end of an iteration, when there
* has been a SwitchAtNextIteration call during the iteration. The driver
* should return and pass the control to the new driver shortly after.
* Monitor must be held.
*/
void SetCurrentDriver(GraphDriver* aDriver) {
MOZ_ASSERT_IF(mGraphDriverRunning, InDriverIteration(mDriver));
MOZ_ASSERT_IF(!mGraphDriverRunning, NS_IsMainThread());
MonitorAutoLock lock(GetMonitor());
mDriver = aDriver;
}
GraphDriver* NextDriver() const {
MOZ_ASSERT(OnGraphThread());
return mNextDriver;
}
bool Switching() const { return NextDriver(); }
void SwitchAtNextIteration(GraphDriver* aNextDriver);
Monitor& GetMonitor() { return mMonitor; }
void EnsureNextIteration() { CurrentDriver()->EnsureNextIteration(); }
// Capture API. This allows to get a mixed-down output for a window.
void RegisterCaptureTrackForWindow(uint64_t aWindowId,
ProcessedMediaTrack* aCaptureTrack);
void UnregisterCaptureTrackForWindow(uint64_t aWindowId);
already_AddRefed<MediaInputPort> ConnectToCaptureTrack(
uint64_t aWindowId, MediaTrack* aMediaTrack);
Watchable<GraphTime>& CurrentTime() override;
/**
* Interrupt any JS running on the graph thread.
* Called on the main thread when shutting down the graph.
*/
void InterruptJS();
class TrackSet {
public:
class iterator {
public:
explicit iterator(MediaTrackGraphImpl& aGraph)
: mGraph(&aGraph), mArrayNum(-1), mArrayIndex(0) {
++(*this);
}
iterator() : mGraph(nullptr), mArrayNum(2), mArrayIndex(0) {}
MediaTrack* operator*() { return Array()->ElementAt(mArrayIndex); }
iterator operator++() {
++mArrayIndex;
while (mArrayNum < 2 &&
(mArrayNum < 0 || mArrayIndex >= Array()->Length())) {
++mArrayNum;
mArrayIndex = 0;
}
return *this;
}
bool operator==(const iterator& aOther) const {
return mArrayNum == aOther.mArrayNum &&
mArrayIndex == aOther.mArrayIndex;
}
bool operator!=(const iterator& aOther) const {
return !(*this == aOther);
}
private:
nsTArray<MediaTrack*>* Array() {
return mArrayNum == 0 ? &mGraph->mTracks : &mGraph->mSuspendedTracks;
}
MediaTrackGraphImpl* mGraph;
int mArrayNum;
uint32_t mArrayIndex;
};
explicit TrackSet(MediaTrackGraphImpl& aGraph) : mGraph(aGraph) {}
iterator begin() { return iterator(mGraph); }
iterator end() { return iterator(); }
private:
MediaTrackGraphImpl& mGraph;
};
TrackSet AllTracks() { return TrackSet(*this); }
// Data members
/*
* If set, the GraphRunner class handles handing over data from audio
* callbacks to a common single thread, shared across GraphDrivers.
*/
const RefPtr<GraphRunner> mGraphRunner;
/**
* Main-thread view of the number of tracks in this graph, for lifetime
* management.
*
* When this becomes zero, the graph is marked as forbidden to add more
* tracks to. It will be shut down shortly after.
*/
size_t mMainThreadTrackCount = 0;
/**
* Main-thread view of the number of ports in this graph, to catch bugs.
*
* When this becomes zero, and mMainThreadTrackCount is 0, the graph is
* marked as forbidden to add more ControlMessages to. It will be shut down
* shortly after.
*/
size_t mMainThreadPortCount = 0;
/**
* Graphs own owning references to their driver, until shutdown. When a driver
* switch occur, previous driver is either deleted, or it's ownership is
* passed to a event that will take care of the asynchronous cleanup, as
* audio track can take some time to shut down.
* Accessed on both the main thread and the graph thread; both read and write.
* Must hold monitor to access it.
*/
RefPtr<GraphDriver> mDriver;
// Set during an iteration to switch driver after the iteration has finished.
// Should the current iteration be the last iteration, the next driver will be
// discarded. Access through SwitchAtNextIteration()/NextDriver(). Graph
// thread only.
RefPtr<GraphDriver> mNextDriver;
// The following state is managed on the graph thread only, unless
// mLifecycleState > LIFECYCLE_RUNNING in which case the graph thread
// is not running and this state can be used from the main thread.
/**
* The graph keeps a reference to each track.
* References are maintained manually to simplify reordering without
* unnecessary thread-safe refcount changes.
* Must satisfy OnGraphThreadOrNotRunning().
*/
nsTArray<MediaTrack*> mTracks;
/**
* This stores MediaTracks that are part of suspended AudioContexts.
* mTracks and mSuspendTracks are disjoint sets: a track is either suspended
* or not suspended. Suspended tracks are not ordered in UpdateTrackOrder,
* and are therefore not doing any processing.
* Must satisfy OnGraphThreadOrNotRunning().
*/
nsTArray<MediaTrack*> mSuspendedTracks;
/**
* Tracks from mFirstCycleBreaker to the end of mTracks produce output before
* they receive input. They correspond to DelayNodes that are in cycles.
*/
uint32_t mFirstCycleBreaker;
/**
* Blocking decisions have been computed up to this time.
* Between each iteration, this is the same as mProcessedTime.
*/
GraphTime mStateComputedTime = 0;
/**
* All track contents have been computed up to this time.
* The next batch of updates from the main thread will be processed
* at this time. This is behind mStateComputedTime during processing.
*/
GraphTime mProcessedTime = 0;
/**
* The end of the current iteration. Only access on the graph thread.
*/
GraphTime mIterationEndTime = 0;
/**
* The graph should stop processing at this time.
*/
GraphTime mEndTime;
/**
* Date of the last time we updated the main thread with the graph state.
*/
TimeStamp mLastMainThreadUpdate;
/**
* Number of active MediaInputPorts
*/
int32_t mPortCount;
/**
* Runnables to run after the next update to main thread state, but that are
* still waiting for the next iteration to finish.
*/
nsTArray<nsCOMPtr<nsIRunnable>> mPendingUpdateRunnables;
/**
* Devices to use for cubeb input & output, or nullptr for default device.
* A MediaTrackGraph always has an output (even if silent).
* If `mInputDeviceUsers.Count() != 0`, this MediaTrackGraph wants audio
* input.
*
* All mInputDeviceID access is on the graph thread except for reads via
* InputDeviceID(), which are racy but used only for comparison.
*
* In any case, the number of channels to use can be queried (on the graph
* thread) by AudioInputChannelCount() and AudioOutputChannelCount().
*/
std::atomic<CubebUtils::AudioDeviceID> mInputDeviceID;
CubebUtils::AudioDeviceID mOutputDeviceID;
// Maps AudioDeviceID to an array of their users (that are listeners). This is
// used to deliver audio input frames and to notify the listeners that the
// audio device that delivers the audio frames has changed.
// This is only touched on the graph thread.
nsDataHashtable<nsVoidPtrHashKey, nsTArray<RefPtr<AudioDataListener>>>
mInputDeviceUsers;
// Only valid for the current iteration: if non nullptr, there is input data.
const AudioDataValue* mInputData;
uint32_t mInputChannelCount;
uint32_t mInputFrames;
/**
* List of resume operations waiting for a switch to an AudioCallbackDriver.
*/
class PendingResumeOperation {
public:
explicit PendingResumeOperation(
AudioContextOperationControlMessage* aMessage);
void Apply(MediaTrackGraphImpl* aGraph);
void Abort();
MediaTrack* DestinationTrack() const { return mDestinationTrack; }
private:
RefPtr<MediaTrack> mDestinationTrack;
nsTArray<RefPtr<MediaTrack>> mTracks;
MozPromiseHolder<AudioContextOperationPromise> mHolder;
};
AutoTArray<PendingResumeOperation, 1> mPendingResumeOperations;
// mMonitor guards the data below.
// MediaTrackGraph normally does its work without holding mMonitor, so it is
// not safe to just grab mMonitor from some thread and start monkeying with
// the graph. Instead, communicate with the graph thread using provided
// mechanisms such as the ControlMessage queue.
Monitor mMonitor;
// Data guarded by mMonitor (must always be accessed with mMonitor held,
// regardless of the value of mLifecycleState).
/**
* State to copy to main thread
*/
nsTArray<TrackUpdate> mTrackUpdates;
/**
* Runnables to run after the next update to main thread state.
*/
nsTArray<nsCOMPtr<nsIRunnable>> mUpdateRunnables;
/**
* A list of batches of messages to process. Each batch is processed
* as an atomic unit.
*/
/*
* Message queue processed by the MTG thread during an iteration.
* Accessed on graph thread only.
*/
nsTArray<MessageBlock> mFrontMessageQueue;
/*
* Message queue in which the main thread appends messages.
* Access guarded by mMonitor.
*/
nsTArray<MessageBlock> mBackMessageQueue;
/* True if there will messages to process if we swap the message queues. */
bool MessagesQueued() const {
mMonitor.AssertCurrentThreadOwns();
return !mBackMessageQueue.IsEmpty();
}
/**
* This enum specifies where this graph is in its lifecycle. This is used
* to control shutdown.
* Shutdown is tricky because it can happen in two different ways:
* 1) Shutdown due to inactivity. RunThread() detects that it has no
* pending messages and no tracks, and exits. The next RunInStableState()
* checks if there are new pending messages from the main thread (true only
* if new track creation raced with shutdown); if there are, it revives
* RunThread(), otherwise it commits to shutting down the graph. New track
* creation after this point will create a new graph. An async event is
* dispatched to Shutdown() the graph's threads and then delete the graph
* object.
* 2) Forced shutdown at application shutdown, completion of a non-realtime
* graph, or document unload. A flag is set, RunThread() detects the flag
* and exits, the next RunInStableState() detects the flag, and dispatches
* the async event to Shutdown() the graph's threads. However the graph
* object is not deleted. New messages for the graph are processed
* synchronously on the main thread if necessary. When the last track is
* destroyed, the graph object is deleted.
*
* This should be kept in sync with the LifecycleState_str array in
* MediaTrackGraph.cpp
*/
enum LifecycleState {
// The graph thread hasn't started yet.
LIFECYCLE_THREAD_NOT_STARTED,
// RunThread() is running normally.
LIFECYCLE_RUNNING,
// In the following states, the graph thread is not running so
// all "graph thread only" state in this class can be used safely
// on the main thread.
// RunThread() has exited and we're waiting for the next
// RunInStableState(), at which point we can clean up the main-thread
// side of the graph.
LIFECYCLE_WAITING_FOR_MAIN_THREAD_CLEANUP,
// RunInStableState() posted a ShutdownRunnable, and we're waiting for it
// to shut down the graph thread(s).
LIFECYCLE_WAITING_FOR_THREAD_SHUTDOWN,
// Graph threads have shut down but we're waiting for remaining tracks
// to be destroyed. Only happens during application shutdown and on
// completed non-realtime graphs, since normally we'd only shut down a
// realtime graph when it has no tracks.
LIFECYCLE_WAITING_FOR_TRACK_DESTRUCTION
};
/**
* Modified only in mMonitor. Transitions to
* LIFECYCLE_WAITING_FOR_MAIN_THREAD_CLEANUP occur on the graph thread at
* the end of an iteration. All other transitions occur on the main thread.
*/
LifecycleState mLifecycleState;
LifecycleState& LifecycleStateRef() {
#if DEBUG
if (mGraphDriverRunning) {
mMonitor.AssertCurrentThreadOwns();
} else {
MOZ_ASSERT(NS_IsMainThread());
}
#endif
return mLifecycleState;
}
const LifecycleState& LifecycleStateRef() const {
#if DEBUG
if (mGraphDriverRunning) {
mMonitor.AssertCurrentThreadOwns();
} else {
MOZ_ASSERT(NS_IsMainThread());
}
#endif
return mLifecycleState;
}
/**
* True once the graph thread has received the message from ForceShutDown().
* This is checked in the decision to shut down the
* graph thread so that control messages dispatched before forced shutdown
* are processed on the graph thread.
* Only set on the graph thread.
* Can be read safely on the thread currently owning the graph, as indicated
* by mLifecycleState.
*/
bool mForceShutDownReceived = false;
/**
* true when InterruptJS() has been called, because shutdown (normal or
* forced) has commenced. Set on the main thread under mMonitor and read on
* the graph thread under mMonitor.
**/
bool mInterruptJSCalled = false;
/**
* Remove this blocker to unblock shutdown.
* Only accessed on the main thread.
**/
RefPtr<media::ShutdownBlocker> mShutdownBlocker;
/**
* True when we have posted an event to the main thread to run
* RunInStableState() and the event hasn't run yet.
* Accessed on both main and MTG thread, mMonitor must be held.
*/
bool mPostedRunInStableStateEvent;
/**
* The JSContext of the graph thread. Set under mMonitor on only the graph
* or GraphRunner thread. Once set this does not change until reset when
* the thread is about to exit. Read under mMonitor on the main thread to
* interrupt running JS for forced shutdown.
**/
JSContext* mJSContext = nullptr;
// Main thread only
/**
* Messages posted by the current event loop task. These are forwarded to
* the media graph thread during RunInStableState. We can't forward them
* immediately because we want all messages between stable states to be
* processed as an atomic batch.
*/
nsTArray<UniquePtr<ControlMessage>> mCurrentTaskMessageQueue;
/**
* True from when RunInStableState sets mLifecycleState to LIFECYCLE_RUNNING,
* until RunInStableState has determined that mLifecycleState is >
* LIFECYCLE_RUNNING.
*/
Atomic<bool> mGraphDriverRunning;
/**
* True when a stable state runner has been posted to the appshell to run
* RunInStableState at the next stable state.
* Only accessed on the main thread.
*/
bool mPostedRunInStableState;
/**
* True when processing real-time audio/video. False when processing
* non-realtime audio.
*/
const bool mRealtime;
/**
* True when a change has happened which requires us to recompute the track
* blocking order.
*/
bool mTrackOrderDirty;
const RefPtr<AbstractThread> mAbstractMainThread;
// used to limit graph shutdown time
// Only accessed on the main thread.
nsCOMPtr<nsITimer> mShutdownTimer;
private:
virtual ~MediaTrackGraphImpl();
MOZ_DEFINE_MALLOC_SIZE_OF(MallocSizeOf)
/**
* This class uses manual memory management, and all pointers to it are raw
* pointers. However, in order for it to implement nsIMemoryReporter, it needs
* to implement nsISupports and so be ref-counted. So it maintains a single
* nsRefPtr to itself, giving it a ref-count of 1 during its entire lifetime,
* and Destroy() nulls this self-reference in order to trigger self-deletion.
*/
RefPtr<MediaTrackGraphImpl> mSelfRef;
struct WindowAndTrack {
uint64_t mWindowId;
RefPtr<ProcessedMediaTrack> mCaptureTrackSink;
};
/**
* Track for window audio capture.
*/
nsTArray<WindowAndTrack> mWindowCaptureTracks;
/**
* Tracks that have their audio output mixed and written to an audio output
* device.
*/
nsTArray<TrackKeyAndVolume> mAudioOutputs;
/**
* Global volume scale. Used when running tests so that the output is not too
* loud.
*/
const float mGlobalVolume;
#ifdef DEBUG
/**
* Used to assert when AppendMessage() runs ControlMessages synchronously.
*/
bool mCanRunMessagesSynchronously;
#endif
/**
* The graph's main-thread observable graph time.
* Updated by the stable state runnable after each iteration.
*/
Watchable<GraphTime> mMainThreadGraphTime;
/**
* Set based on mProcessedTime at end of iteration.
* Read by stable state runnable on main thread. Protected by mMonitor.
*/
GraphTime mNextMainThreadGraphTime = 0;
/**
* Cached audio output latency, in seconds. Main thread only. This is reset
* whenever the audio device running this MediaTrackGraph changes.
*/
double mAudioOutputLatency;
/**
* The max audio output channel count the default audio output device
* supports. This is cached here because it can be expensive to query. The
* cache is invalidated when the device is changed. This is initialized in the
* ctor, and the read/write only on the graph thread.
*/
uint32_t mMaxOutputChannelCount;
};
} // namespace mozilla
#endif /* MEDIATRACKGRAPHIMPL_H_ */