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/* -*- 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 "mozilla/dom/WorkerRef.h"
#include "nsDebug.h"
#include "WorkerRunnable.h"
#include "WorkerPrivate.h"
namespace mozilla::dom {
namespace {
// This runnable is used to release the StrongWorkerRef on the worker thread
// when a ThreadSafeWorkerRef is released.
class ReleaseRefControlRunnable final : public WorkerControlRunnable {
public:
ReleaseRefControlRunnable(WorkerPrivate* aWorkerPrivate,
already_AddRefed<StrongWorkerRef> aRef)
: WorkerControlRunnable("ReleaseRefControlRunnable"),
mRef(std::move(aRef)) {
MOZ_ASSERT(mRef);
}
bool PreDispatch(WorkerPrivate* aWorkerPrivate) override { return true; }
void PostDispatch(WorkerPrivate* aWorkerPrivate,
bool aDispatchResult) override {}
bool WorkerRun(JSContext* aCx, WorkerPrivate* aWorkerPrivate) override {
mRef = nullptr;
return true;
}
private:
RefPtr<StrongWorkerRef> mRef;
};
} // namespace
// ----------------------------------------------------------------------------
// WorkerRef
WorkerRef::WorkerRef(WorkerPrivate* aWorkerPrivate, const char* aName,
bool aIsPreventingShutdown)
:
#ifdef DEBUG
mDebugMutex("WorkerRef"),
#endif
mWorkerPrivate(aWorkerPrivate),
mName(aName),
mIsPreventingShutdown(aIsPreventingShutdown),
mHolding(false) {
MOZ_ASSERT(aWorkerPrivate);
MOZ_ASSERT(aName);
aWorkerPrivate->AssertIsOnWorkerThread();
}
WorkerRef::~WorkerRef() {
NS_ASSERT_OWNINGTHREAD(WorkerRef);
ReleaseWorker();
}
void WorkerRef::ReleaseWorker() {
if (mHolding) {
MOZ_ASSERT(mWorkerPrivate);
if (mIsPreventingShutdown) {
mWorkerPrivate->AssertIsNotPotentiallyLastGCCCRunning();
}
mWorkerPrivate->RemoveWorkerRef(this);
mWorkerPrivate = nullptr;
mHolding = false;
}
}
bool WorkerRef::HoldWorker(WorkerStatus aStatus) {
MOZ_ASSERT(mWorkerPrivate);
MOZ_ASSERT(!mHolding);
if (NS_WARN_IF(!mWorkerPrivate->AddWorkerRef(this, aStatus))) {
return false;
}
mHolding = true;
return true;
}
void WorkerRef::Notify() {
NS_ASSERT_OWNINGTHREAD(WorkerRef);
if (!mCallback) {
return;
}
MoveOnlyFunction<void()> callback = std::move(mCallback);
MOZ_ASSERT(!mCallback);
callback();
}
// ----------------------------------------------------------------------------
// WeakWorkerRef
/* static */
already_AddRefed<WeakWorkerRef> WeakWorkerRef::Create(
WorkerPrivate* aWorkerPrivate, MoveOnlyFunction<void()>&& aCallback) {
MOZ_ASSERT(aWorkerPrivate);
aWorkerPrivate->AssertIsOnWorkerThread();
RefPtr<WeakWorkerRef> ref = new WeakWorkerRef(aWorkerPrivate);
if (!ref->HoldWorker(Canceling)) {
return nullptr;
}
ref->mCallback = std::move(aCallback);
return ref.forget();
}
WeakWorkerRef::WeakWorkerRef(WorkerPrivate* aWorkerPrivate)
: WorkerRef(aWorkerPrivate, "WeakWorkerRef", false) {}
WeakWorkerRef::~WeakWorkerRef() = default;
void WeakWorkerRef::Notify() {
MOZ_ASSERT(mHolding);
MOZ_ASSERT(mWorkerPrivate);
// Notify could drop the last reference to this object. We must keep it alive
// in order to call ReleaseWorker() immediately after.
RefPtr<WeakWorkerRef> kungFuGrip = this;
WorkerRef::Notify();
ReleaseWorker();
}
WorkerPrivate* WeakWorkerRef::GetPrivate() const {
NS_ASSERT_OWNINGTHREAD(WeakWorkerRef);
return mWorkerPrivate;
}
WorkerPrivate* WeakWorkerRef::GetUnsafePrivate() const {
return mWorkerPrivate;
}
// ----------------------------------------------------------------------------
// StrongWorkerRef
/* static */
already_AddRefed<StrongWorkerRef> StrongWorkerRef::Create(
WorkerPrivate* const aWorkerPrivate, const char* const aName,
MoveOnlyFunction<void()>&& aCallback) {
if (RefPtr<StrongWorkerRef> ref =
CreateImpl(aWorkerPrivate, aName, Canceling)) {
ref->mCallback = std::move(aCallback);
return ref.forget();
}
return nullptr;
}
/* static */
already_AddRefed<StrongWorkerRef> StrongWorkerRef::CreateForcibly(
WorkerPrivate* const aWorkerPrivate, const char* const aName) {
return CreateImpl(aWorkerPrivate, aName, Killing);
}
/* static */
already_AddRefed<StrongWorkerRef> StrongWorkerRef::CreateImpl(
WorkerPrivate* const aWorkerPrivate, const char* const aName,
WorkerStatus const aFailStatus) {
MOZ_ASSERT(aWorkerPrivate);
MOZ_ASSERT(aName);
RefPtr<StrongWorkerRef> ref = new StrongWorkerRef(aWorkerPrivate, aName);
if (!ref->HoldWorker(aFailStatus)) {
return nullptr;
}
return ref.forget();
}
StrongWorkerRef::StrongWorkerRef(WorkerPrivate* aWorkerPrivate,
const char* aName)
: WorkerRef(aWorkerPrivate, aName, true) {}
StrongWorkerRef::~StrongWorkerRef() = default;
WorkerPrivate* StrongWorkerRef::Private() const {
NS_ASSERT_OWNINGTHREAD(StrongWorkerRef);
return mWorkerPrivate;
}
// ----------------------------------------------------------------------------
// ThreadSafeWorkerRef
ThreadSafeWorkerRef::ThreadSafeWorkerRef(StrongWorkerRef* aRef) : mRef(aRef) {
MOZ_ASSERT(aRef);
aRef->Private()->AssertIsOnWorkerThread();
}
ThreadSafeWorkerRef::~ThreadSafeWorkerRef() {
// Let's release the StrongWorkerRef on the correct thread.
if (!mRef->mWorkerPrivate->IsOnWorkerThread()) {
WorkerPrivate* workerPrivate = mRef->mWorkerPrivate;
RefPtr<ReleaseRefControlRunnable> r =
new ReleaseRefControlRunnable(workerPrivate, mRef.forget());
r->Dispatch(workerPrivate);
return;
}
}
WorkerPrivate* ThreadSafeWorkerRef::Private() const {
return mRef->mWorkerPrivate;
}
// ----------------------------------------------------------------------------
// IPCWorkerRef
/* static */
already_AddRefed<IPCWorkerRef> IPCWorkerRef::Create(
WorkerPrivate* aWorkerPrivate, const char* aName,
MoveOnlyFunction<void()>&& aCallback) {
MOZ_ASSERT(aWorkerPrivate);
aWorkerPrivate->AssertIsOnWorkerThread();
RefPtr<IPCWorkerRef> ref = new IPCWorkerRef(aWorkerPrivate, aName);
if (!ref->HoldWorker(Canceling)) {
return nullptr;
}
ref->SetActorCount(1);
ref->mCallback = std::move(aCallback);
return ref.forget();
}
IPCWorkerRef::IPCWorkerRef(WorkerPrivate* aWorkerPrivate, const char* aName)
: WorkerRef(aWorkerPrivate, aName, false), mActorCount(0) {}
IPCWorkerRef::~IPCWorkerRef() {
NS_ASSERT_OWNINGTHREAD(IPCWorkerRef);
// explicit type convertion to avoid undefined behavior of uint32_t overflow.
mWorkerPrivate->AdjustNonblockingCCBackgroundActorCount(
(int32_t)-mActorCount);
ReleaseWorker();
};
WorkerPrivate* IPCWorkerRef::Private() const {
NS_ASSERT_OWNINGTHREAD(IPCWorkerRef);
return mWorkerPrivate;
}
void IPCWorkerRef::SetActorCount(uint32_t aCount) {
NS_ASSERT_OWNINGTHREAD(IPCWorkerRef);
// explicit type convertion to avoid undefined behavior of uint32_t overflow.
mWorkerPrivate->AdjustNonblockingCCBackgroundActorCount((int32_t)aCount -
(int32_t)mActorCount);
mActorCount = aCount;
}
} // namespace mozilla::dom