gecko-dev/dom/ipc/VsyncParent.cpp

104 lines
3.0 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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 "VsyncParent.h"
#include "mozilla/Unused.h"
#include "nsThreadUtils.h"
#include "nsIThread.h"
namespace mozilla::dom {
VsyncParent::VsyncParent()
: mObservingVsync(false),
mDestroyed(false),
mInitialThread(NS_GetCurrentThread()) {}
void VsyncParent::UpdateVsyncDispatcher(
const RefPtr<VsyncDispatcher>& aVsyncDispatcher) {
if (aVsyncDispatcher == mVsyncDispatcher) {
return;
}
if (mObservingVsync && mVsyncDispatcher) {
mVsyncDispatcher->RemoveVsyncObserver(this);
}
mVsyncDispatcher = aVsyncDispatcher;
if (mObservingVsync) {
mVsyncDispatcher->AddVsyncObserver(this);
}
}
void VsyncParent::NotifyVsync(const VsyncEvent& aVsync) {
if (IsOnInitialThread()) {
DispatchVsyncEvent(aVsync);
return;
}
// Called on hardware vsync thread. We should post to current ipc thread.
nsCOMPtr<nsIRunnable> vsyncEvent = NewRunnableMethod<VsyncEvent>(
"dom::VsyncParent::DispatchVsyncEvent", this,
&VsyncParent::DispatchVsyncEvent, aVsync);
MOZ_ALWAYS_SUCCEEDS(NS_DispatchToThreadQueue(
vsyncEvent.forget(), mInitialThread, EventQueuePriority::Vsync));
}
void VsyncParent::DispatchVsyncEvent(const VsyncEvent& aVsync) {
AssertIsOnInitialThread();
// If we call NotifyVsync() when we handle ActorDestroy() message, we might
// still call DispatchVsyncEvent().
// Similarly, we might also receive RecvUnobserveVsync() when call
// NotifyVsync(). We use mObservingVsync and mDestroyed flags to skip this
// notification.
if (mObservingVsync && !mDestroyed) {
TimeDuration vsyncRate = mVsyncDispatcher->GetVsyncRate();
Unused << SendNotify(aVsync, vsyncRate.ToMilliseconds());
}
}
mozilla::ipc::IPCResult VsyncParent::RecvObserve() {
AssertIsOnInitialThread();
if (!mObservingVsync) {
if (mVsyncDispatcher) {
mVsyncDispatcher->AddVsyncObserver(this);
}
mObservingVsync = true;
return IPC_OK();
}
return IPC_FAIL_NO_REASON(this);
}
mozilla::ipc::IPCResult VsyncParent::RecvUnobserve() {
AssertIsOnInitialThread();
if (mObservingVsync) {
if (mVsyncDispatcher) {
mVsyncDispatcher->RemoveVsyncObserver(this);
}
mObservingVsync = false;
return IPC_OK();
}
return IPC_FAIL_NO_REASON(this);
}
void VsyncParent::ActorDestroy(ActorDestroyReason aActorDestroyReason) {
MOZ_ASSERT(!mDestroyed);
AssertIsOnInitialThread();
if (mObservingVsync && mVsyncDispatcher) {
mVsyncDispatcher->RemoveVsyncObserver(this);
}
mVsyncDispatcher = nullptr;
mDestroyed = true;
}
bool VsyncParent::IsOnInitialThread() {
return NS_GetCurrentThread() == mInitialThread;
}
void VsyncParent::AssertIsOnInitialThread() { MOZ_ASSERT(IsOnInitialThread()); }
} // namespace mozilla::dom