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media / audio / audio_output_device.cc [blame]
// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "media/audio/audio_output_device.h"
#include <stddef.h>
#include <stdint.h>
#include <cmath>
#include <memory>
#include <utility>
#include "base/functional/callback_helpers.h"
#include "base/logging.h"
#include "base/metrics/histogram_macros.h"
#include "base/synchronization/waitable_event.h"
#include "base/task/bind_post_task.h"
#include "base/task/sequenced_task_runner.h"
#include "base/task/single_thread_task_runner.h"
#include "base/threading/platform_thread.h"
#include "base/threading/thread_restrictions.h"
#include "base/timer/timer.h"
#include "base/trace_event/trace_event.h"
#include "build/build_config.h"
#include "media/audio/audio_device_description.h"
#include "media/audio/audio_output_device_thread_callback.h"
#include "media/base/limits.h"
namespace media {
AudioOutputDevice::AudioOutputDevice(
std::unique_ptr<AudioOutputIPC> ipc,
const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner,
const AudioSinkParameters& sink_params,
base::TimeDelta authorization_timeout)
: io_task_runner_(io_task_runner),
callback_(nullptr),
ipc_(std::move(ipc)),
state_(IDLE),
session_id_(sink_params.session_id),
device_id_(sink_params.device_id),
stopping_hack_(false),
did_receive_auth_(base::WaitableEvent::ResetPolicy::MANUAL,
base::WaitableEvent::InitialState::NOT_SIGNALED),
output_params_(AudioParameters::UnavailableDeviceParams()),
device_status_(OUTPUT_DEVICE_STATUS_ERROR_INTERNAL),
auth_timeout_(authorization_timeout) {
DCHECK(ipc_);
DCHECK(io_task_runner_);
}
void AudioOutputDevice::Initialize(const AudioParameters& params,
RenderCallback* callback) {
CHECK(params.IsValid());
io_task_runner_->PostTask(
FROM_HERE,
base::BindOnce(&AudioOutputDevice::InitializeOnIOThread, this, params,
// The lifecycle of `callback` is controlled by the owner
// who is responsible for calling Stop before deallocating
// it. InitializeOnIOThread verifies this before using
// callback and we would not want to try to persist the
// object here as it would break the ownership model.
base::UnsafeDangling(callback)));
}
void AudioOutputDevice::InitializeOnIOThread(
const AudioParameters& params,
MayBeDangling<RenderCallback> callback) {
DCHECK(!callback_) << "Calling Initialize() twice?";
DCHECK(params.IsValid());
DVLOG(1) << __func__ << ": " << params.AsHumanReadableString();
audio_parameters_ = params;
base::AutoLock auto_lock(audio_thread_lock_);
// If Stop() has already been called, RenderCallback has already been
// destroyed. So |callback| would be a dangling pointer.
if (!stopping_hack_)
callback_ = callback;
}
AudioOutputDevice::~AudioOutputDevice() {
{
// Abort any pending callbacks. Technically we don't need to acquire the
// lock here since there should be no other calls outstanding, but because
// we've used the GUARDED_BY compiler syntax, we'll get an error without it.
base::AutoLock auto_lock(device_info_lock_);
if (pending_device_info_cb_) {
std::move(pending_device_info_cb_)
.Run(OutputDeviceInfo(OUTPUT_DEVICE_STATUS_ERROR_INTERNAL));
}
}
#if DCHECK_IS_ON()
// Make sure we've stopped the stream properly before destructing |this|.
DCHECK(audio_thread_lock_.Try());
DCHECK_EQ(state_, IDLE);
DCHECK(!audio_thread_);
DCHECK(!audio_callback_);
DCHECK(!stopping_hack_);
audio_thread_lock_.Release();
#endif // DCHECK_IS_ON()
}
void AudioOutputDevice::RequestDeviceAuthorization() {
TRACE_EVENT0("audio", "AudioOutputDevice::RequestDeviceAuthorization");
io_task_runner_->PostTask(
FROM_HERE,
base::BindOnce(&AudioOutputDevice::RequestDeviceAuthorizationOnIOThread,
this));
}
void AudioOutputDevice::Start() {
TRACE_EVENT0("audio", "AudioOutputDevice::Start");
io_task_runner_->PostTask(
FROM_HERE,
base::BindOnce(&AudioOutputDevice::CreateStreamOnIOThread, this));
}
void AudioOutputDevice::Stop() {
TRACE_EVENT0("audio", "AudioOutputDevice::Stop");
{
base::ScopedAllowBaseSyncPrimitives allow;
base::AutoLock auto_lock(audio_thread_lock_);
audio_thread_.reset();
stopping_hack_ = true;
}
io_task_runner_->PostTask(
FROM_HERE, base::BindOnce(&AudioOutputDevice::ShutDownOnIOThread, this));
}
void AudioOutputDevice::Play() {
TRACE_EVENT0("audio", "AudioOutputDevice::Play");
io_task_runner_->PostTask(
FROM_HERE, base::BindOnce(&AudioOutputDevice::PlayOnIOThread, this));
}
void AudioOutputDevice::Pause() {
TRACE_EVENT0("audio", "AudioOutputDevice::Pause");
io_task_runner_->PostTask(
FROM_HERE, base::BindOnce(&AudioOutputDevice::PauseOnIOThread, this));
}
void AudioOutputDevice::Flush() {
TRACE_EVENT0("audio", "AudioOutputDevice::Flush");
io_task_runner_->PostTask(
FROM_HERE, base::BindOnce(&AudioOutputDevice::FlushOnIOThread, this));
}
bool AudioOutputDevice::SetVolume(double volume) {
TRACE_EVENT1("audio", "AudioOutputDevice::Pause", "volume", volume);
if (volume < 0 || volume > 1.0)
return false;
return io_task_runner_->PostTask(
FROM_HERE,
base::BindOnce(&AudioOutputDevice::SetVolumeOnIOThread, this, volume));
}
OutputDeviceInfo AudioOutputDevice::GetOutputDeviceInfo() {
TRACE_EVENT0("audio", "AudioOutputDevice::GetOutputDeviceInfo");
DCHECK(!io_task_runner_->BelongsToCurrentThread());
did_receive_auth_.Wait();
return GetOutputDeviceInfo_Signaled();
}
void AudioOutputDevice::GetOutputDeviceInfoAsync(OutputDeviceInfoCB info_cb) {
{
// Hold the lock while checking the signal and setting the pending callback
// to avoid racing with authorization completion on the IO thread.
base::AutoLock auto_lock(device_info_lock_);
if (!did_receive_auth_.IsSignaled()) {
DCHECK(!pending_device_info_cb_);
pending_device_info_cb_ =
base::BindPostTaskToCurrentDefault(std::move(info_cb));
return;
}
}
// Always post to avoid the caller being reentrant. Local testing shows even
// on a powerful desktop, we haven't received device authorization by this
// point when AOD construction and GetOutputDeviceInfoAsync() happen back to
// back (which is the most common use case).
base::SequencedTaskRunner::GetCurrentDefault()->PostTask(
FROM_HERE,
base::BindOnce(std::move(info_cb), GetOutputDeviceInfo_Signaled()));
}
bool AudioOutputDevice::IsOptimizedForHardwareParameters() {
return true;
}
bool AudioOutputDevice::CurrentThreadIsRenderingThread() {
// Since this function is supposed to be called on the rendering thread,
// it's safe to access |audio_callback_| here. It will always be valid when
// the rendering thread is running.
return audio_callback_->CurrentThreadIsAudioDeviceThread();
}
void AudioOutputDevice::RequestDeviceAuthorizationOnIOThread() {
DCHECK(io_task_runner_->BelongsToCurrentThread());
DCHECK_EQ(state_, IDLE);
state_ = AUTHORIZATION_REQUESTED;
ipc_->RequestDeviceAuthorization(this, session_id_, device_id_);
if (auth_timeout_.is_positive()) {
// Create the timer on the thread it's used on. It's guaranteed to be
// deleted on the same thread since users must call Stop() before deleting
// AudioOutputDevice; see ShutDownOnIOThread().
auth_timeout_action_ = std::make_unique<base::OneShotTimer>();
auth_timeout_action_->Start(
FROM_HERE, auth_timeout_,
base::BindOnce(&AudioOutputDevice::OnDeviceAuthorized, this,
OUTPUT_DEVICE_STATUS_ERROR_TIMED_OUT, AudioParameters(),
std::string()));
}
}
void AudioOutputDevice::CreateStreamOnIOThread() {
TRACE_EVENT0("audio", "AudioOutputDevice::Create");
DCHECK(io_task_runner_->BelongsToCurrentThread());
#if DCHECK_IS_ON()
{
base::AutoLock auto_lock(audio_thread_lock_);
if (!stopping_hack_)
DCHECK(callback_) << "Initialize hasn't been called";
}
#endif
DCHECK_NE(state_, STREAM_CREATION_REQUESTED);
if (!ipc_) {
NotifyRenderCallbackOfError();
return;
}
if (state_ == IDLE && !(did_receive_auth_.IsSignaled() && device_id_.empty()))
RequestDeviceAuthorizationOnIOThread();
ipc_->CreateStream(this, audio_parameters_);
// By default, start playing right away.
ipc_->PlayStream();
state_ = STREAM_CREATION_REQUESTED;
}
void AudioOutputDevice::PlayOnIOThread() {
DCHECK(io_task_runner_->BelongsToCurrentThread());
if (audio_callback_)
audio_callback_->InitializePlayStartTime();
if (ipc_)
ipc_->PlayStream();
}
void AudioOutputDevice::PauseOnIOThread() {
DCHECK(io_task_runner_->BelongsToCurrentThread());
if (ipc_)
ipc_->PauseStream();
}
void AudioOutputDevice::FlushOnIOThread() {
DCHECK(io_task_runner_->BelongsToCurrentThread());
if (ipc_)
ipc_->FlushStream();
}
void AudioOutputDevice::ShutDownOnIOThread() {
DCHECK(io_task_runner_->BelongsToCurrentThread());
if (ipc_)
ipc_->CloseStream();
state_ = IDLE;
// Destoy the timer on the thread it's used on.
auth_timeout_action_.reset();
UMA_HISTOGRAM_ENUMERATION("Media.Audio.Render.StreamCallbackError2",
had_error_);
had_error_ = kNoError;
// We can run into an issue where ShutDownOnIOThread is called right after
// OnStreamCreated is called in cases where Start/Stop are called before we
// get the OnStreamCreated callback. To handle that corner case, we call
// Stop(). In most cases, the thread will already be stopped.
//
// Another situation is when the IO thread goes away before Stop() is called
// in which case, we cannot use the message loop to close the thread handle
// and can't rely on the main thread existing either.
base::AutoLock auto_lock_(audio_thread_lock_);
base::ScopedAllowBaseSyncPrimitivesOutsideBlockingScope allow_thread_join;
audio_thread_.reset();
audio_callback_.reset();
stopping_hack_ = false;
}
void AudioOutputDevice::SetVolumeOnIOThread(double volume) {
DCHECK(io_task_runner_->BelongsToCurrentThread());
if (ipc_)
ipc_->SetVolume(volume);
}
void AudioOutputDevice::OnError() {
TRACE_EVENT0("audio", "AudioOutputDevice::OnError");
DCHECK(io_task_runner_->BelongsToCurrentThread());
// Do nothing if the stream has been closed.
if (state_ == IDLE)
return;
// Don't dereference the callback object if the audio thread
// is stopped or stopping. That could mean that the callback
// object has been deleted.
// TODO(tommi): Add an explicit contract for clearing the callback
// object. Possibly require calling Initialize again or provide
// a callback object via Start() and clear it in Stop().
NotifyRenderCallbackOfError();
}
void AudioOutputDevice::OnDeviceAuthorized(
OutputDeviceStatus device_status,
const AudioParameters& output_params,
const std::string& matched_device_id) {
DCHECK(io_task_runner_->BelongsToCurrentThread());
auth_timeout_action_.reset();
// Do nothing if late authorization is received after timeout.
if (!ipc_)
return;
UMA_HISTOGRAM_BOOLEAN("Media.Audio.Render.OutputDeviceAuthorizationTimedOut",
device_status == OUTPUT_DEVICE_STATUS_ERROR_TIMED_OUT);
LOG_IF(WARNING, device_status == OUTPUT_DEVICE_STATUS_ERROR_TIMED_OUT)
<< "Output device authorization timed out";
// It may happen that a second authorization is received as a result to a
// call to Start() after Stop(). If the status for the second authorization
// differs from the first, it will not be reflected in |device_status_|
// to avoid a race.
// This scenario is unlikely. If it occurs, the new value will be
// different from OUTPUT_DEVICE_STATUS_OK, so the AudioOutputDevice
// will enter the |ipc_| == nullptr state anyway, which is the safe thing to
// do. This is preferable to holding a lock.
if (!did_receive_auth_.IsSignaled()) {
device_status_ = device_status;
UMA_HISTOGRAM_ENUMERATION("Media.Audio.Render.OutputDeviceStatus",
device_status, OUTPUT_DEVICE_STATUS_MAX + 1);
}
if (device_status == OUTPUT_DEVICE_STATUS_OK) {
TRACE_EVENT0("audio", "AudioOutputDevice authorized");
if (!did_receive_auth_.IsSignaled()) {
output_params_ = output_params;
// It's possible to not have a matched device obtained via session id. It
// means matching output device through |session_id_| failed and the
// default device is used.
DCHECK(AudioDeviceDescription::UseSessionIdToSelectDevice(session_id_,
device_id_) ||
matched_device_id_.empty());
matched_device_id_ = matched_device_id;
DVLOG(1) << "AudioOutputDevice authorized, session_id: " << session_id_
<< ", device_id: " << device_id_
<< ", matched_device_id: " << matched_device_id_;
OnAuthSignal();
}
} else {
TRACE_EVENT1("audio", "AudioOutputDevice not authorized", "auth status",
device_status_);
// Closing IPC forces a Signal(), so no clients are locked waiting
// indefinitely after this method returns.
ipc_->CloseStream();
OnIPCClosed();
NotifyRenderCallbackOfError();
}
}
void AudioOutputDevice::OnStreamCreated(
base::UnsafeSharedMemoryRegion shared_memory_region,
base::SyncSocket::ScopedHandle socket_handle,
bool playing_automatically) {
TRACE_EVENT0("audio", "AudioOutputDevice::OnStreamCreated");
DCHECK(io_task_runner_->BelongsToCurrentThread());
DCHECK(shared_memory_region.IsValid());
#if BUILDFLAG(IS_WIN)
DCHECK(socket_handle.IsValid());
#else
DCHECK(socket_handle.is_valid());
#endif
DCHECK_GT(shared_memory_region.GetSize(), 0u);
if (state_ != STREAM_CREATION_REQUESTED)
return;
// We can receive OnStreamCreated() on the IO thread after the client has
// called Stop() but before ShutDownOnIOThread() is processed. In such a
// situation |callback_| might point to freed memory. Instead of starting
// |audio_thread_| do nothing and wait for ShutDownOnIOThread() to get called.
//
// TODO(scherkus): The real fix is to have sane ownership semantics. The fact
// that |callback_| (which should own and outlive this object!) can point to
// freed memory is a mess. AudioRendererSink should be non-refcounted so that
// owners (WebRtcAudioDeviceImpl, AudioRendererImpl, etc...) can Stop() and
// delete as they see fit. AudioOutputDevice should internally use WeakPtr
// to handle teardown and thread hopping. See http://crbug.com/151051 for
// details.
{
base::AutoLock auto_lock(audio_thread_lock_);
if (stopping_hack_)
return;
DCHECK(!audio_thread_);
DCHECK(!audio_callback_);
audio_callback_ = std::make_unique<AudioOutputDeviceThreadCallback>(
audio_parameters_, std::move(shared_memory_region), callback_);
if (playing_automatically)
audio_callback_->InitializePlayStartTime();
audio_thread_ = std::make_unique<AudioDeviceThread>(
audio_callback_.get(), std::move(socket_handle), "AudioOutputDevice",
base::ThreadType::kRealtimeAudio);
}
}
void AudioOutputDevice::OnIPCClosed() {
TRACE_EVENT0("audio", "AudioOutputDevice::OnIPCClosed");
DCHECK(io_task_runner_->BelongsToCurrentThread());
ipc_.reset();
state_ = IDLE;
OnAuthSignal();
}
OutputDeviceInfo AudioOutputDevice::GetOutputDeviceInfo_Signaled() {
DCHECK(did_receive_auth_.IsSignaled());
OutputDeviceInfo info(AudioDeviceDescription::UseSessionIdToSelectDevice(
session_id_, device_id_)
? matched_device_id_
: device_id_,
device_status_, output_params_);
TRACE_EVENT1("audio", "AudioOutputDevice::GetOutputDeviceInfo_Signaled",
"info", info.AsHumanReadableString());
return info;
}
void AudioOutputDevice::OnAuthSignal() {
DCHECK(io_task_runner_->BelongsToCurrentThread());
// This lock is held while signaling to avoid any thread safety issues while
// GetOutputDeviceInfoAsync() may be checking the signal and modifying the
// |pending_device_info_cb_| on another thread.
//
// We might be able to get away with signaling outside of the lock, but this
// requires more careful construction for anyone checking the signal and
// using the result to set or get the pending callback value. The failure
// mode is also more subtle, callbacks will be lost versus a thread hang which
// is more easily detectable in the production population.
base::AutoLock auto_lock(device_info_lock_);
// Signal to unblock any blocked threads waiting for parameters.
did_receive_auth_.Signal();
// The callback is always posted by way base::BindPostTaskToCurrentDefault()
// usage upon receipt, so this is safe to run under the lock.
if (pending_device_info_cb_)
std::move(pending_device_info_cb_).Run(GetOutputDeviceInfo_Signaled());
}
void AudioOutputDevice::NotifyRenderCallbackOfError() {
TRACE_EVENT0("audio", "AudioOutputDevice::NotifyRenderCallbackOfError");
DCHECK(io_task_runner_->BelongsToCurrentThread());
base::AutoLock auto_lock(audio_thread_lock_);
// Avoid signaling error if Initialize() hasn't been called yet, or if
// Stop() has already been called.
if (callback_ && !stopping_hack_) {
// Update |had_error_| for UMA stats.
if (audio_callback_)
had_error_ = kErrorDuringRendering;
else
had_error_ = kErrorDuringCreation;
callback_->OnRenderError();
}
}
} // namespace media