gecko-dev/dom/media/AudioNotificationReceiver.cpp

87 строки
2.6 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* 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/. */
#include "AudioNotificationReceiver.h"
#include "mozilla/Logging.h" // for LazyLogModule
#include "mozilla/StaticMutex.h" // for StaticMutex
#include "mozilla/StaticPtr.h" // for StaticAutoPtr
#include "nsAppRunner.h" // for XRE_IsContentProcess
#include "nsTArray.h" // for nsTArray
static mozilla::LazyLogModule sLogger("AudioNotificationReceiver");
#undef ANR_LOG
#define ANR_LOG(...) MOZ_LOG(sLogger, mozilla::LogLevel::Debug, (__VA_ARGS__))
#undef ANR_LOGW
#define ANR_LOGW(...) MOZ_LOG(sLogger, mozilla::LogLevel::Warning, (__VA_ARGS__))
namespace mozilla {
namespace audio {
/*
* A list containing all clients subscribering the device-changed notifications.
*/
static StaticAutoPtr<nsTArray<DeviceChangeListener*>> sSubscribers;
static StaticMutex sMutex;
/*
* AudioNotificationReceiver Implementation
*/
/* static */ void
AudioNotificationReceiver::Register(DeviceChangeListener* aDeviceChangeListener)
{
MOZ_ASSERT(XRE_IsContentProcess());
StaticMutexAutoLock lock(sMutex);
if (!sSubscribers) {
sSubscribers = new nsTArray<DeviceChangeListener*>();
}
sSubscribers->AppendElement(aDeviceChangeListener);
ANR_LOG("The DeviceChangeListener: %p is registered successfully.",
aDeviceChangeListener);
}
/* static */ void
AudioNotificationReceiver::Unregister(DeviceChangeListener* aDeviceChangeListener)
{
MOZ_ASSERT(XRE_IsContentProcess());
StaticMutexAutoLock lock(sMutex);
MOZ_ASSERT(!sSubscribers->IsEmpty(), "No subscriber.");
sSubscribers->RemoveElement(aDeviceChangeListener);
if (sSubscribers->IsEmpty()) {
// Clear the static pointer here to prevent memory leak.
sSubscribers = nullptr;
}
ANR_LOG("The DeviceChangeListener: %p is unregistered successfully.",
aDeviceChangeListener);
}
/* static */ void
AudioNotificationReceiver::NotifyDefaultDeviceChanged()
{
MOZ_ASSERT(XRE_IsContentProcess());
StaticMutexAutoLock lock(sMutex);
// Do nothing when there is no DeviceChangeListener.
if (!sSubscribers) {
return;
}
for (DeviceChangeListener* stream : *sSubscribers) {
ANR_LOG("Notify the DeviceChangeListener: %p "
"that the default device has been changed.", stream);
stream->ResetDefaultDevice();
}
}
} // namespace audio
} // namespace mozilla