diff options
Diffstat (limited to 'dom/messagechannel/MessagePort.cpp')
| -rw-r--r-- | dom/messagechannel/MessagePort.cpp | 874 |
1 files changed, 874 insertions, 0 deletions
diff --git a/dom/messagechannel/MessagePort.cpp b/dom/messagechannel/MessagePort.cpp new file mode 100644 index 0000000000..736909bc2d --- /dev/null +++ b/dom/messagechannel/MessagePort.cpp @@ -0,0 +1,874 @@ +/* -*- 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 "MessagePort.h" + +#include "MessageEvent.h" +#include "MessagePortChild.h" +#include "mozilla/dom/BlobBinding.h" +#include "mozilla/dom/Event.h" +#include "mozilla/dom/File.h" +#include "mozilla/dom/MessageChannel.h" +#include "mozilla/dom/MessageEventBinding.h" +#include "mozilla/dom/MessagePortBinding.h" +#include "mozilla/dom/MessagePortChild.h" +#include "mozilla/dom/PMessagePort.h" +#include "mozilla/dom/RootedDictionary.h" +#include "mozilla/dom/ScriptSettings.h" +#include "mozilla/dom/StructuredCloneTags.h" +#include "mozilla/dom/WorkerCommon.h" +#include "mozilla/dom/WorkerRef.h" +#include "mozilla/dom/WorkerScope.h" +#include "mozilla/ipc/BackgroundChild.h" +#include "mozilla/dom/RefMessageBodyService.h" +#include "mozilla/dom/SharedMessageBody.h" +#include "mozilla/ipc/PBackgroundChild.h" +#include "mozilla/MessagePortTimelineMarker.h" +#include "mozilla/ScopeExit.h" +#include "mozilla/TimelineConsumers.h" +#include "mozilla/TimelineMarker.h" +#include "mozilla/Unused.h" +#include "nsContentUtils.h" +#include "nsGlobalWindow.h" +#include "nsPresContext.h" + +#ifdef XP_WIN +# undef PostMessage +#endif + +namespace mozilla::dom { + +void UniqueMessagePortId::ForceClose() { + if (!mIdentifier.neutered()) { + MessagePort::ForceClose(mIdentifier); + mIdentifier.neutered() = true; + } +} + +class PostMessageRunnable final : public CancelableRunnable { + friend class MessagePort; + + public: + PostMessageRunnable(MessagePort* aPort, SharedMessageBody* aData) + : CancelableRunnable("dom::PostMessageRunnable"), + mPort(aPort), + mData(aData) { + MOZ_ASSERT(aPort); + MOZ_ASSERT(aData); + } + + NS_IMETHOD + Run() override { + NS_ASSERT_OWNINGTHREAD(Runnable); + + // The port can be cycle collected while this runnable is pending in + // the event queue. + if (!mPort) { + return NS_OK; + } + + MOZ_ASSERT(mPort->mPostMessageRunnable == this); + + DispatchMessage(); + + // We must check if we were waiting for this message in order to shutdown + // the port. + mPort->UpdateMustKeepAlive(); + + mPort->mPostMessageRunnable = nullptr; + mPort->Dispatch(); + + return NS_OK; + } + + nsresult Cancel() override { + NS_ASSERT_OWNINGTHREAD(Runnable); + + mPort = nullptr; + mData = nullptr; + return NS_OK; + } + + private: + void DispatchMessage() const { + NS_ASSERT_OWNINGTHREAD(Runnable); + + if (NS_FAILED(mPort->CheckCurrentGlobalCorrectness())) { + return; + } + + nsCOMPtr<nsIGlobalObject> globalObject = mPort->GetParentObject(); + + AutoJSAPI jsapi; + if (!globalObject || !jsapi.Init(globalObject)) { + NS_WARNING("Failed to initialize AutoJSAPI object."); + return; + } + + JSContext* cx = jsapi.cx(); + + IgnoredErrorResult rv; + JS::Rooted<JS::Value> value(cx); + + UniquePtr<AbstractTimelineMarker> start; + UniquePtr<AbstractTimelineMarker> end; + bool isTimelineRecording = !TimelineConsumers::IsEmpty(); + + if (isTimelineRecording) { + start = MakeUnique<MessagePortTimelineMarker>( + ProfileTimelineMessagePortOperationType::DeserializeData, + MarkerTracingType::START); + } + + mData->Read(cx, &value, mPort->mRefMessageBodyService, + SharedMessageBody::ReadMethod::StealRefMessageBody, rv); + + if (isTimelineRecording) { + end = MakeUnique<MessagePortTimelineMarker>( + ProfileTimelineMessagePortOperationType::DeserializeData, + MarkerTracingType::END); + TimelineConsumers::AddMarkerForAllObservedDocShells(start); + TimelineConsumers::AddMarkerForAllObservedDocShells(end); + } + + if (NS_WARN_IF(rv.Failed())) { + JS_ClearPendingException(cx); + mPort->DispatchError(); + return; + } + + // Create the event + nsCOMPtr<mozilla::dom::EventTarget> eventTarget = + do_QueryInterface(mPort->GetOwner()); + RefPtr<MessageEvent> event = + new MessageEvent(eventTarget, nullptr, nullptr); + + Sequence<OwningNonNull<MessagePort>> ports; + if (!mData->TakeTransferredPortsAsSequence(ports)) { + mPort->DispatchError(); + return; + } + + event->InitMessageEvent(nullptr, u"message"_ns, CanBubble::eNo, + Cancelable::eNo, value, u""_ns, u""_ns, nullptr, + ports); + event->SetTrusted(true); + + mPort->DispatchEvent(*event); + } + + private: + ~PostMessageRunnable() = default; + + RefPtr<MessagePort> mPort; + RefPtr<SharedMessageBody> mData; +}; + +NS_IMPL_CYCLE_COLLECTION_CLASS(MessagePort) + +NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(MessagePort, + DOMEventTargetHelper) + if (tmp->mPostMessageRunnable) { + NS_IMPL_CYCLE_COLLECTION_UNLINK(mPostMessageRunnable->mPort); + } + + NS_IMPL_CYCLE_COLLECTION_UNLINK(mMessagesForTheOtherPort); + + tmp->CloseForced(); +NS_IMPL_CYCLE_COLLECTION_UNLINK_END + +NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(MessagePort, + DOMEventTargetHelper) + if (tmp->mPostMessageRunnable) { + NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPostMessageRunnable->mPort); + } + + NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mUnshippedEntangledPort); +NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END + +NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(MessagePort) +NS_INTERFACE_MAP_END_INHERITING(DOMEventTargetHelper) + +NS_IMPL_ADDREF_INHERITED(MessagePort, DOMEventTargetHelper) +NS_IMPL_RELEASE_INHERITED(MessagePort, DOMEventTargetHelper) + +MessagePort::MessagePort(nsIGlobalObject* aGlobal, State aState) + : DOMEventTargetHelper(aGlobal), + mRefMessageBodyService(RefMessageBodyService::GetOrCreate()), + mState(aState), + mMessageQueueEnabled(false), + mIsKeptAlive(false), + mHasBeenTransferredOrClosed(false) { + MOZ_ASSERT(aGlobal); + + mIdentifier = MakeUnique<MessagePortIdentifier>(); + mIdentifier->neutered() = true; + mIdentifier->sequenceId() = 0; +} + +MessagePort::~MessagePort() { + CloseForced(); + MOZ_ASSERT(!mActor); + if (mActor) { + mActor->SetPort(nullptr); + mActor = nullptr; + } + MOZ_ASSERT(!mWorkerRef); +} + +/* static */ +already_AddRefed<MessagePort> MessagePort::Create(nsIGlobalObject* aGlobal, + const nsID& aUUID, + const nsID& aDestinationUUID, + ErrorResult& aRv) { + MOZ_ASSERT(aGlobal); + + RefPtr<MessagePort> mp = new MessagePort(aGlobal, eStateUnshippedEntangled); + mp->Initialize(aUUID, aDestinationUUID, 1 /* 0 is an invalid sequence ID */, + false /* Neutered */, aRv); + return mp.forget(); +} + +/* static */ +already_AddRefed<MessagePort> MessagePort::Create( + nsIGlobalObject* aGlobal, UniqueMessagePortId& aIdentifier, + ErrorResult& aRv) { + MOZ_ASSERT(aGlobal); + + RefPtr<MessagePort> mp = new MessagePort(aGlobal, eStateEntangling); + mp->Initialize(aIdentifier.uuid(), aIdentifier.destinationUuid(), + aIdentifier.sequenceId(), aIdentifier.neutered(), aRv); + aIdentifier.neutered() = true; + return mp.forget(); +} + +void MessagePort::UnshippedEntangle(MessagePort* aEntangledPort) { + MOZ_DIAGNOSTIC_ASSERT(aEntangledPort); + MOZ_DIAGNOSTIC_ASSERT(!mUnshippedEntangledPort); + + mUnshippedEntangledPort = aEntangledPort; +} + +void MessagePort::Initialize(const nsID& aUUID, const nsID& aDestinationUUID, + uint32_t aSequenceID, bool aNeutered, + ErrorResult& aRv) { + MOZ_ASSERT(mIdentifier); + mIdentifier->uuid() = aUUID; + mIdentifier->destinationUuid() = aDestinationUUID; + mIdentifier->sequenceId() = aSequenceID; + + if (aNeutered) { + // If this port is neutered we don't want to keep it alive artificially nor + // we want to add listeners or WorkerRefs. + mState = eStateDisentangled; + return; + } + + if (mState == eStateEntangling) { + if (!ConnectToPBackground()) { + aRv.Throw(NS_ERROR_FAILURE); + return; + } + } else { + MOZ_ASSERT(mState == eStateUnshippedEntangled); + } + + // The port has to keep itself alive until it's entangled. + UpdateMustKeepAlive(); + + if (WorkerPrivate* workerPrivate = GetCurrentThreadWorkerPrivate()) { + RefPtr<MessagePort> self = this; + + // When the callback is executed, we cannot process messages anymore because + // we cannot dispatch new runnables. Let's force a Close(). + RefPtr<StrongWorkerRef> strongWorkerRef = StrongWorkerRef::Create( + workerPrivate, "MessagePort", [self]() { self->CloseForced(); }); + if (NS_WARN_IF(!strongWorkerRef)) { + // The worker is shutting down. + CloseForced(); + aRv.Throw(NS_ERROR_FAILURE); + return; + } + + MOZ_ASSERT(!mWorkerRef); + mWorkerRef = std::move(strongWorkerRef); + } +} + +JSObject* MessagePort::WrapObject(JSContext* aCx, + JS::Handle<JSObject*> aGivenProto) { + return MessagePort_Binding::Wrap(aCx, this, aGivenProto); +} + +void MessagePort::PostMessage(JSContext* aCx, JS::Handle<JS::Value> aMessage, + const Sequence<JSObject*>& aTransferable, + ErrorResult& aRv) { + // We *must* clone the data here, or the JS::Value could be modified + // by script + + // Here we want to check if the transerable object list contains + // this port. + for (uint32_t i = 0; i < aTransferable.Length(); ++i) { + JS::Rooted<JSObject*> object(aCx, aTransferable[i]); + if (!object) { + continue; + } + + MessagePort* port = nullptr; + nsresult rv = UNWRAP_OBJECT(MessagePort, &object, port); + if (NS_SUCCEEDED(rv) && port == this) { + aRv.Throw(NS_ERROR_DOM_DATA_CLONE_ERR); + return; + } + } + + JS::Rooted<JS::Value> transferable(aCx, JS::UndefinedValue()); + + aRv = nsContentUtils::CreateJSValueFromSequenceOfObject(aCx, aTransferable, + &transferable); + if (NS_WARN_IF(aRv.Failed())) { + return; + } + + Maybe<nsID> agentClusterId; + nsCOMPtr<nsIGlobalObject> global = GetOwnerGlobal(); + if (global) { + agentClusterId = global->GetAgentClusterId(); + } + + RefPtr<SharedMessageBody> data = new SharedMessageBody( + StructuredCloneHolder::TransferringSupported, agentClusterId); + + UniquePtr<AbstractTimelineMarker> start; + UniquePtr<AbstractTimelineMarker> end; + bool isTimelineRecording = !TimelineConsumers::IsEmpty(); + + if (isTimelineRecording) { + start = MakeUnique<MessagePortTimelineMarker>( + ProfileTimelineMessagePortOperationType::SerializeData, + MarkerTracingType::START); + } + + data->Write(aCx, aMessage, transferable, mIdentifier->uuid(), + mRefMessageBodyService, aRv); + + if (isTimelineRecording) { + end = MakeUnique<MessagePortTimelineMarker>( + ProfileTimelineMessagePortOperationType::SerializeData, + MarkerTracingType::END); + TimelineConsumers::AddMarkerForAllObservedDocShells(start); + TimelineConsumers::AddMarkerForAllObservedDocShells(end); + } + + if (NS_WARN_IF(aRv.Failed())) { + return; + } + + // This message has to be ignored. + if (mState > eStateEntangled) { + return; + } + + // If we are unshipped we are connected to the other port on the same thread. + if (mState == eStateUnshippedEntangled) { + MOZ_DIAGNOSTIC_ASSERT(mUnshippedEntangledPort); + mUnshippedEntangledPort->mMessages.AppendElement(data); + mUnshippedEntangledPort->Dispatch(); + return; + } + + // Not entangled yet, but already closed/disentangled. + if (mState == eStateEntanglingForDisentangle || + mState == eStateEntanglingForClose) { + return; + } + + RemoveDocFromBFCache(); + + // Not entangled yet. + if (mState == eStateEntangling) { + mMessagesForTheOtherPort.AppendElement(data); + return; + } + + MOZ_ASSERT(mActor); + MOZ_ASSERT(mMessagesForTheOtherPort.IsEmpty()); + + AutoTArray<RefPtr<SharedMessageBody>, 1> array; + array.AppendElement(data); + + AutoTArray<MessageData, 1> messages; + // note: `messages` will borrow the underlying buffer, but this is okay + // because reverse destruction order means `messages` will be destroyed prior + // to `array`/`data`. + SharedMessageBody::FromSharedToMessagesChild(mActor->Manager(), array, + messages); + mActor->SendPostMessages(messages); +} + +void MessagePort::PostMessage(JSContext* aCx, JS::Handle<JS::Value> aMessage, + const StructuredSerializeOptions& aOptions, + ErrorResult& aRv) { + PostMessage(aCx, aMessage, aOptions.mTransfer, aRv); +} + +void MessagePort::Start() { + if (mMessageQueueEnabled) { + return; + } + + mMessageQueueEnabled = true; + Dispatch(); +} + +void MessagePort::Dispatch() { + if (!mMessageQueueEnabled || mMessages.IsEmpty() || mPostMessageRunnable) { + return; + } + + switch (mState) { + case eStateUnshippedEntangled: + // Everything is fine here. We have messages because the other + // port populates our queue directly. + break; + + case eStateEntangling: + // Everything is fine here as well. We have messages because the other + // port populated our queue directly when we were in the + // eStateUnshippedEntangled state. + break; + + case eStateEntanglingForDisentangle: + // Here we don't want to ship messages because these messages must be + // delivered by the cloned version of this one. They will be sent in the + // SendDisentangle(). + return; + + case eStateEntanglingForClose: + // We still want to deliver messages if we are closing. These messages + // are here from the previous eStateUnshippedEntangled state. + break; + + case eStateEntangled: + // This port is up and running. + break; + + case eStateDisentangling: + // If we are in the process to disentangle the port, we cannot dispatch + // messages. They will be sent to the cloned version of this port via + // SendDisentangle(); + return; + + case eStateDisentangled: + MOZ_CRASH("This cannot happen."); + // It cannot happen because Disentangle should take off all the pending + // messages. + break; + + case eStateDisentangledForClose: + // If we are here is because the port has been closed. We can still + // process the pending messages. + break; + } + + RefPtr<SharedMessageBody> data = mMessages.ElementAt(0); + mMessages.RemoveElementAt(0); + + mPostMessageRunnable = new PostMessageRunnable(this, data); + + nsCOMPtr<nsIGlobalObject> global = GetOwnerGlobal(); + if (NS_IsMainThread() && global) { + MOZ_ALWAYS_SUCCEEDS( + global->Dispatch(TaskCategory::Other, do_AddRef(mPostMessageRunnable))); + return; + } + + MOZ_ALWAYS_SUCCEEDS(NS_DispatchToCurrentThread(mPostMessageRunnable)); +} + +void MessagePort::Close() { + mHasBeenTransferredOrClosed = true; + CloseInternal(true /* aSoftly */); +} + +void MessagePort::CloseForced() { CloseInternal(false /* aSoftly */); } + +void MessagePort::CloseInternal(bool aSoftly) { + // If we have some messages to send but we don't want a 'soft' close, we have + // to flush them now. + if (!aSoftly) { + mMessages.Clear(); + } + + // Let's inform the RefMessageBodyService that any our shared messages are + // now invalid. + mRefMessageBodyService->ForgetPort(mIdentifier->uuid()); + + if (mState == eStateUnshippedEntangled) { + MOZ_DIAGNOSTIC_ASSERT(mUnshippedEntangledPort); + + // This avoids loops. + RefPtr<MessagePort> port = std::move(mUnshippedEntangledPort); + + mState = eStateDisentangledForClose; + port->CloseInternal(aSoftly); + + UpdateMustKeepAlive(); + return; + } + + // Not entangled yet, we have to wait. + if (mState == eStateEntangling) { + mState = eStateEntanglingForClose; + return; + } + + // Not entangled but already cloned or closed + if (mState == eStateEntanglingForDisentangle || + mState == eStateEntanglingForClose) { + return; + } + + // Maybe we were already closing the port but softly. In this case we call + // UpdateMustKeepAlive() to consider the empty pending message queue. + if (mState == eStateDisentangledForClose && !aSoftly) { + UpdateMustKeepAlive(); + return; + } + + if (mState > eStateEntangled) { + return; + } + + // We don't care about stopping the sending of messages because from now all + // the incoming messages will be ignored. + mState = eStateDisentangledForClose; + + MOZ_ASSERT(mActor); + + mActor->SendClose(); + mActor->SetPort(nullptr); + mActor = nullptr; + + UpdateMustKeepAlive(); +} + +EventHandlerNonNull* MessagePort::GetOnmessage() { + return GetEventHandler(nsGkAtoms::onmessage); +} + +void MessagePort::SetOnmessage(EventHandlerNonNull* aCallback) { + SetEventHandler(nsGkAtoms::onmessage, aCallback); + + // When using onmessage, the call to start() is implied. + Start(); +} + +// This method is called when the PMessagePortChild actor is entangled to +// another actor. It receives a list of messages to be dispatch. It can be that +// we were waiting for this entangling step in order to disentangle the port or +// to close it. +void MessagePort::Entangled(nsTArray<MessageData>& aMessages) { + MOZ_ASSERT(mState == eStateEntangling || + mState == eStateEntanglingForDisentangle || + mState == eStateEntanglingForClose); + + State oldState = mState; + mState = eStateEntangled; + + // If we have pending messages, these have to be sent. + if (!mMessagesForTheOtherPort.IsEmpty()) { + { + nsTArray<MessageData> messages; + SharedMessageBody::FromSharedToMessagesChild( + mActor->Manager(), mMessagesForTheOtherPort, messages); + mActor->SendPostMessages(messages); + } + // Because `messages` borrow the underlying JSStructuredCloneData buffers, + // only clear after `messages` have gone out of scope. + mMessagesForTheOtherPort.Clear(); + } + + // We must convert the messages into SharedMessageBodys to avoid leaks. + FallibleTArray<RefPtr<SharedMessageBody>> data; + if (NS_WARN_IF( + !SharedMessageBody::FromMessagesToSharedChild(aMessages, data))) { + DispatchError(); + return; + } + + // If the next step is to close the port, we do it ignoring the received + // messages. + if (oldState == eStateEntanglingForClose) { + CloseForced(); + return; + } + + mMessages.AppendElements(data); + + // We were waiting for the entangling callback in order to disentangle this + // port immediately after. + if (oldState == eStateEntanglingForDisentangle) { + StartDisentangling(); + return; + } + + Dispatch(); +} + +void MessagePort::StartDisentangling() { + MOZ_ASSERT(mActor); + MOZ_ASSERT(mState == eStateEntangled); + + mState = eStateDisentangling; + + // Sending this message we communicate to the parent actor that we don't want + // to receive any new messages. It is possible that a message has been + // already sent but not received yet. So we have to collect all of them and + // we send them in the SendDispatch() request. + mActor->SendStopSendingData(); +} + +void MessagePort::MessagesReceived(nsTArray<MessageData>& aMessages) { + MOZ_ASSERT(mState == eStateEntangled || mState == eStateDisentangling || + // This last step can happen only if Close() has been called + // manually. At this point SendClose() is sent but we can still + // receive something until the Closing request is processed. + mState == eStateDisentangledForClose); + MOZ_ASSERT(mMessagesForTheOtherPort.IsEmpty()); + + RemoveDocFromBFCache(); + + FallibleTArray<RefPtr<SharedMessageBody>> data; + if (NS_WARN_IF( + !SharedMessageBody::FromMessagesToSharedChild(aMessages, data))) { + DispatchError(); + return; + } + + mMessages.AppendElements(data); + + if (mState == eStateEntangled) { + Dispatch(); + } +} + +void MessagePort::StopSendingDataConfirmed() { + MOZ_ASSERT(mState == eStateDisentangling); + MOZ_ASSERT(mActor); + + Disentangle(); +} + +void MessagePort::Disentangle() { + MOZ_ASSERT(mState == eStateDisentangling); + MOZ_ASSERT(mActor); + + mState = eStateDisentangled; + + { + nsTArray<MessageData> messages; + SharedMessageBody::FromSharedToMessagesChild(mActor->Manager(), mMessages, + messages); + mActor->SendDisentangle(messages); + } + + // Let's inform the RefMessageBodyService that any our shared messages are + // now invalid. + mRefMessageBodyService->ForgetPort(mIdentifier->uuid()); + + // Only clear mMessages after the MessageData instances have gone out of scope + // because they borrow mMessages' underlying JSStructuredCloneDatas. + mMessages.Clear(); + + mActor->SetPort(nullptr); + mActor = nullptr; + + UpdateMustKeepAlive(); +} + +void MessagePort::CloneAndDisentangle(UniqueMessagePortId& aIdentifier) { + MOZ_ASSERT(mIdentifier); + MOZ_ASSERT(!mHasBeenTransferredOrClosed); + + mHasBeenTransferredOrClosed = true; + + // We can clone a port that has already been transfered. In this case, on the + // otherside will have a neutered port. Here we set neutered to true so that + // we are safe in case a early return. + aIdentifier.neutered() = true; + + if (mState > eStateEntangled) { + return; + } + + // We already have a 'next step'. We have to consider this port as already + // cloned/closed/disentangled. + if (mState == eStateEntanglingForDisentangle || + mState == eStateEntanglingForClose) { + return; + } + + aIdentifier.uuid() = mIdentifier->uuid(); + aIdentifier.destinationUuid() = mIdentifier->destinationUuid(); + aIdentifier.sequenceId() = mIdentifier->sequenceId() + 1; + aIdentifier.neutered() = false; + + // We have to entangle first. + if (mState == eStateUnshippedEntangled) { + MOZ_ASSERT(mUnshippedEntangledPort); + MOZ_ASSERT(mMessagesForTheOtherPort.IsEmpty()); + + RefPtr<MessagePort> port = std::move(mUnshippedEntangledPort); + + // Disconnect the entangled port and connect it to PBackground. + if (!port->ConnectToPBackground()) { + // We are probably shutting down. We cannot proceed. + mState = eStateDisentangled; + UpdateMustKeepAlive(); + return; + } + + // In this case, we don't need to be connected to the PBackground service. + if (mMessages.IsEmpty()) { + aIdentifier.sequenceId() = mIdentifier->sequenceId(); + + mState = eStateDisentangled; + UpdateMustKeepAlive(); + return; + } + + // Register this component to PBackground. + if (!ConnectToPBackground()) { + // We are probably shutting down. We cannot proceed. + return; + } + + mState = eStateEntanglingForDisentangle; + return; + } + + // Not entangled yet, we have to wait. + if (mState == eStateEntangling) { + mState = eStateEntanglingForDisentangle; + return; + } + + MOZ_ASSERT(mState == eStateEntangled); + StartDisentangling(); +} + +void MessagePort::Closed() { + if (mState >= eStateDisentangled) { + return; + } + + mState = eStateDisentangledForClose; + + if (mActor) { + mActor->SetPort(nullptr); + mActor = nullptr; + } + + UpdateMustKeepAlive(); +} + +bool MessagePort::ConnectToPBackground() { + RefPtr<MessagePort> self = this; + auto raii = MakeScopeExit([self] { + self->mState = eStateDisentangled; + self->UpdateMustKeepAlive(); + }); + + mozilla::ipc::PBackgroundChild* actorChild = + mozilla::ipc::BackgroundChild::GetOrCreateForCurrentThread(); + if (NS_WARN_IF(!actorChild)) { + return false; + } + + PMessagePortChild* actor = actorChild->SendPMessagePortConstructor( + mIdentifier->uuid(), mIdentifier->destinationUuid(), + mIdentifier->sequenceId()); + if (NS_WARN_IF(!actor)) { + return false; + } + + mActor = static_cast<MessagePortChild*>(actor); + MOZ_ASSERT(mActor); + + mActor->SetPort(this); + mState = eStateEntangling; + + raii.release(); + return true; +} + +void MessagePort::UpdateMustKeepAlive() { + if (mState >= eStateDisentangled && mMessages.IsEmpty() && mIsKeptAlive) { + mIsKeptAlive = false; + + // The DTOR of this WorkerRef will release the worker for us. + mWorkerRef = nullptr; + + Release(); + return; + } + + if (mState < eStateDisentangled && !mIsKeptAlive) { + mIsKeptAlive = true; + AddRef(); + } +} + +void MessagePort::DisconnectFromOwner() { + CloseForced(); + DOMEventTargetHelper::DisconnectFromOwner(); +} + +void MessagePort::RemoveDocFromBFCache() { + if (!NS_IsMainThread()) { + return; + } + + if (nsPIDOMWindowInner* window = GetOwner()) { + window->RemoveFromBFCacheSync(); + } +} + +/* static */ +void MessagePort::ForceClose(const MessagePortIdentifier& aIdentifier) { + mozilla::ipc::PBackgroundChild* actorChild = + mozilla::ipc::BackgroundChild::GetOrCreateForCurrentThread(); + if (NS_WARN_IF(!actorChild)) { + MOZ_CRASH("Failed to create a PBackgroundChild actor!"); + } + + Unused << actorChild->SendMessagePortForceClose(aIdentifier.uuid(), + aIdentifier.destinationUuid(), + aIdentifier.sequenceId()); +} + +void MessagePort::DispatchError() { + nsCOMPtr<nsIGlobalObject> globalObject = GetParentObject(); + + AutoJSAPI jsapi; + if (!globalObject || !jsapi.Init(globalObject)) { + NS_WARNING("Failed to initialize AutoJSAPI object."); + return; + } + + RootedDictionary<MessageEventInit> init(jsapi.cx()); + init.mBubbles = false; + init.mCancelable = false; + + RefPtr<Event> event = + MessageEvent::Constructor(this, u"messageerror"_ns, init); + event->SetTrusted(true); + + DispatchEvent(*event); +} + +} // namespace mozilla::dom |