michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "MessagePort.h"
michael@0: #include "MessageEvent.h"
michael@0: #include "mozilla/dom/Event.h"
michael@0: #include "mozilla/dom/MessageChannel.h"
michael@0: #include "mozilla/dom/MessagePortBinding.h"
michael@0: #include "mozilla/dom/MessagePortList.h"
michael@0: #include "mozilla/dom/StructuredCloneTags.h"
michael@0: #include "nsContentUtils.h"
michael@0: #include "nsGlobalWindow.h"
michael@0: #include "nsPresContext.h"
michael@0: 
michael@0: #include "nsIDocument.h"
michael@0: #include "nsIDOMFile.h"
michael@0: #include "nsIDOMFileList.h"
michael@0: #include "nsIPresShell.h"
michael@0: 
michael@0: namespace mozilla {
michael@0: namespace dom {
michael@0: 
michael@0: class DispatchEventRunnable : public nsRunnable
michael@0: {
michael@0:   friend class MessagePort;
michael@0: 
michael@0:   public:
michael@0:     DispatchEventRunnable(MessagePort* aPort)
michael@0:       : mPort(aPort)
michael@0:     {
michael@0:     }
michael@0: 
michael@0:     NS_IMETHOD
michael@0:     Run()
michael@0:     {
michael@0:       nsRefPtr<DispatchEventRunnable> mKungFuDeathGrip(this);
michael@0: 
michael@0:       mPort->mDispatchRunnable = nullptr;
michael@0:       mPort->Dispatch();
michael@0: 
michael@0:       return NS_OK;
michael@0:     }
michael@0: 
michael@0:   private:
michael@0:     nsRefPtr<MessagePort> mPort;
michael@0: };
michael@0: 
michael@0: class PostMessageRunnable : public nsRunnable
michael@0: {
michael@0:   friend class MessagePort;
michael@0: 
michael@0:   public:
michael@0:     NS_DECL_NSIRUNNABLE
michael@0: 
michael@0:     PostMessageRunnable()
michael@0:     {
michael@0:     }
michael@0: 
michael@0:     ~PostMessageRunnable()
michael@0:     {
michael@0:     }
michael@0: 
michael@0:     JSAutoStructuredCloneBuffer& Buffer()
michael@0:     {
michael@0:       return mBuffer;
michael@0:     }
michael@0: 
michael@0:     bool StoreISupports(nsISupports* aSupports)
michael@0:     {
michael@0:       mSupportsArray.AppendElement(aSupports);
michael@0:       return true;
michael@0:     }
michael@0: 
michael@0:     void Dispatch(MessagePort* aPort)
michael@0:     {
michael@0:       mPort = aPort;
michael@0:       NS_DispatchToCurrentThread(this);
michael@0:     }
michael@0: 
michael@0:   private:
michael@0:     nsRefPtr<MessagePort> mPort;
michael@0:     JSAutoStructuredCloneBuffer mBuffer;
michael@0: 
michael@0:     nsTArray<nsCOMPtr<nsISupports> > mSupportsArray;
michael@0: };
michael@0: 
michael@0: namespace {
michael@0: 
michael@0: struct StructuredCloneInfo
michael@0: {
michael@0:   PostMessageRunnable* mEvent;
michael@0:   MessagePort* mPort;
michael@0:   nsRefPtrHashtable<nsRefPtrHashKey<MessagePortBase>, MessagePortBase> mPorts;
michael@0: };
michael@0: 
michael@0: static JSObject*
michael@0: PostMessageReadStructuredClone(JSContext* cx,
michael@0:                                JSStructuredCloneReader* reader,
michael@0:                                uint32_t tag,
michael@0:                                uint32_t data,
michael@0:                                void* closure)
michael@0: {
michael@0:   if (tag == SCTAG_DOM_BLOB || tag == SCTAG_DOM_FILELIST) {
michael@0:     NS_ASSERTION(!data, "Data should be empty");
michael@0: 
michael@0:     nsISupports* supports;
michael@0:     if (JS_ReadBytes(reader, &supports, sizeof(supports))) {
michael@0:       JS::Rooted<JS::Value> val(cx);
michael@0:       if (NS_SUCCEEDED(nsContentUtils::WrapNative(cx, supports, &val))) {
michael@0:         return JSVAL_TO_OBJECT(val);
michael@0:       }
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   const JSStructuredCloneCallbacks* runtimeCallbacks =
michael@0:     js::GetContextStructuredCloneCallbacks(cx);
michael@0: 
michael@0:   if (runtimeCallbacks) {
michael@0:     return runtimeCallbacks->read(cx, reader, tag, data, nullptr);
michael@0:   }
michael@0: 
michael@0:   return nullptr;
michael@0: }
michael@0: 
michael@0: static bool
michael@0: PostMessageWriteStructuredClone(JSContext* cx,
michael@0:                                 JSStructuredCloneWriter* writer,
michael@0:                                 JS::Handle<JSObject*> obj,
michael@0:                                 void *closure)
michael@0: {
michael@0:   StructuredCloneInfo* scInfo = static_cast<StructuredCloneInfo*>(closure);
michael@0:   NS_ASSERTION(scInfo, "Must have scInfo!");
michael@0: 
michael@0:   nsCOMPtr<nsIXPConnectWrappedNative> wrappedNative;
michael@0:   nsContentUtils::XPConnect()->
michael@0:     GetWrappedNativeOfJSObject(cx, obj, getter_AddRefs(wrappedNative));
michael@0:   if (wrappedNative) {
michael@0:     uint32_t scTag = 0;
michael@0:     nsISupports* supports = wrappedNative->Native();
michael@0: 
michael@0:     nsCOMPtr<nsIDOMBlob> blob = do_QueryInterface(supports);
michael@0:     if (blob) {
michael@0:       scTag = SCTAG_DOM_BLOB;
michael@0:     }
michael@0: 
michael@0:     nsCOMPtr<nsIDOMFileList> list = do_QueryInterface(supports);
michael@0:     if (list) {
michael@0:       scTag = SCTAG_DOM_FILELIST;
michael@0:     }
michael@0: 
michael@0:     if (scTag) {
michael@0:       return JS_WriteUint32Pair(writer, scTag, 0) &&
michael@0:              JS_WriteBytes(writer, &supports, sizeof(supports)) &&
michael@0:              scInfo->mEvent->StoreISupports(supports);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   const JSStructuredCloneCallbacks* runtimeCallbacks =
michael@0:     js::GetContextStructuredCloneCallbacks(cx);
michael@0: 
michael@0:   if (runtimeCallbacks) {
michael@0:     return runtimeCallbacks->write(cx, writer, obj, nullptr);
michael@0:   }
michael@0: 
michael@0:   return false;
michael@0: }
michael@0: 
michael@0: static bool
michael@0: PostMessageReadTransferStructuredClone(JSContext* aCx,
michael@0:                                        JSStructuredCloneReader* reader,
michael@0:                                        uint32_t tag, void* data,
michael@0:                                        uint64_t unused,
michael@0:                                        void* aClosure,
michael@0:                                        JS::MutableHandle<JSObject*> returnObject)
michael@0: {
michael@0:   StructuredCloneInfo* scInfo = static_cast<StructuredCloneInfo*>(aClosure);
michael@0:   NS_ASSERTION(scInfo, "Must have scInfo!");
michael@0: 
michael@0:   if (tag == SCTAG_DOM_MAP_MESSAGEPORT) {
michael@0:     MessagePort* port = static_cast<MessagePort*>(data);
michael@0:     port->BindToOwner(scInfo->mPort->GetOwner());
michael@0:     scInfo->mPorts.Put(port, nullptr);
michael@0: 
michael@0:     JS::Rooted<JSObject*> obj(aCx, port->WrapObject(aCx));
michael@0:     if (JS_WrapObject(aCx, &obj)) {
michael@0:       MOZ_ASSERT(port->GetOwner() == scInfo->mPort->GetOwner());
michael@0:       returnObject.set(obj);
michael@0:     }
michael@0:     return true;
michael@0:   }
michael@0: 
michael@0:   return false;
michael@0: }
michael@0: 
michael@0: static bool
michael@0: PostMessageTransferStructuredClone(JSContext* aCx,
michael@0:                                    JS::Handle<JSObject*> aObj,
michael@0:                                    void* aClosure,
michael@0:                                    uint32_t* aTag,
michael@0:                                    JS::TransferableOwnership* aOwnership,
michael@0:                                    void** aContent,
michael@0:                                    uint64_t *aExtraData)
michael@0: {
michael@0:   StructuredCloneInfo* scInfo = static_cast<StructuredCloneInfo*>(aClosure);
michael@0:   NS_ASSERTION(scInfo, "Must have scInfo!");
michael@0: 
michael@0:   MessagePortBase *port = nullptr;
michael@0:   nsresult rv = UNWRAP_OBJECT(MessagePort, aObj, port);
michael@0:   if (NS_SUCCEEDED(rv)) {
michael@0:     nsRefPtr<MessagePortBase> newPort;
michael@0:     if (scInfo->mPorts.Get(port, getter_AddRefs(newPort))) {
michael@0:       // No duplicate.
michael@0:       return false;
michael@0:     }
michael@0: 
michael@0:     newPort = port->Clone();
michael@0:     scInfo->mPorts.Put(port, newPort);
michael@0: 
michael@0:     *aTag = SCTAG_DOM_MAP_MESSAGEPORT;
michael@0:     *aOwnership = JS::SCTAG_TMO_CUSTOM;
michael@0:     *aContent = newPort;
michael@0:     *aExtraData = 0;
michael@0: 
michael@0:     return true;
michael@0:   }
michael@0: 
michael@0:   return false;
michael@0: }
michael@0: 
michael@0: static void
michael@0: PostMessageFreeTransferStructuredClone(uint32_t aTag, JS::TransferableOwnership aOwnership,
michael@0:                                        void* aData,
michael@0:                                        uint64_t aExtraData,
michael@0:                                        void* aClosure)
michael@0: {
michael@0:   StructuredCloneInfo* scInfo = static_cast<StructuredCloneInfo*>(aClosure);
michael@0:   NS_ASSERTION(scInfo, "Must have scInfo!");
michael@0: 
michael@0:   if (aTag == SCTAG_DOM_MAP_MESSAGEPORT) {
michael@0:     MOZ_ASSERT(aOwnership == JS::SCTAG_TMO_CUSTOM);
michael@0:     nsRefPtr<MessagePort> port(static_cast<MessagePort*>(aData));
michael@0:     scInfo->mPorts.Remove(port);
michael@0:   }
michael@0: }
michael@0: 
michael@0: JSStructuredCloneCallbacks kPostMessageCallbacks = {
michael@0:   PostMessageReadStructuredClone,
michael@0:   PostMessageWriteStructuredClone,
michael@0:   nullptr,
michael@0:   PostMessageReadTransferStructuredClone,
michael@0:   PostMessageTransferStructuredClone,
michael@0:   PostMessageFreeTransferStructuredClone
michael@0: };
michael@0: 
michael@0: } // anonymous namespace
michael@0: 
michael@0: static PLDHashOperator
michael@0: PopulateMessagePortList(MessagePortBase* aKey, MessagePortBase* aValue, void* aClosure)
michael@0: {
michael@0:   nsTArray<nsRefPtr<MessagePortBase> > *array =
michael@0:     static_cast<nsTArray<nsRefPtr<MessagePortBase> > *>(aClosure);
michael@0: 
michael@0:   array->AppendElement(aKey);
michael@0:   return PL_DHASH_NEXT;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: PostMessageRunnable::Run()
michael@0: {
michael@0:   MOZ_ASSERT(mPort);
michael@0: 
michael@0:   // Get the JSContext for the target window
michael@0:   nsCOMPtr<nsIScriptGlobalObject> sgo = do_QueryInterface(mPort->GetOwner());
michael@0:   NS_ENSURE_STATE(sgo);
michael@0:   nsCOMPtr<nsIScriptContext> scriptContext = sgo->GetContext();
michael@0:   AutoPushJSContext cx(scriptContext ? scriptContext->GetNativeContext()
michael@0:                                      : nsContentUtils::GetSafeJSContext());
michael@0: 
michael@0:   MOZ_ASSERT(cx);
michael@0: 
michael@0:   // Deserialize the structured clone data
michael@0:   JS::Rooted<JS::Value> messageData(cx);
michael@0:   StructuredCloneInfo scInfo;
michael@0:   scInfo.mEvent = this;
michael@0:   scInfo.mPort = mPort;
michael@0: 
michael@0:   if (!mBuffer.read(cx, &messageData, &kPostMessageCallbacks, &scInfo)) {
michael@0:     return NS_ERROR_DOM_DATA_CLONE_ERR;
michael@0:   }
michael@0: 
michael@0:   // Create the event
michael@0:   nsCOMPtr<mozilla::dom::EventTarget> eventTarget =
michael@0:     do_QueryInterface(mPort->GetOwner());
michael@0:   nsRefPtr<MessageEvent> event =
michael@0:     new MessageEvent(eventTarget, nullptr, nullptr);
michael@0: 
michael@0:   event->InitMessageEvent(NS_LITERAL_STRING("message"), false /* non-bubbling */,
michael@0:                           false /* cancelable */, messageData, EmptyString(),
michael@0:                           EmptyString(), nullptr);
michael@0:   event->SetTrusted(true);
michael@0:   event->SetSource(mPort);
michael@0: 
michael@0:   nsTArray<nsRefPtr<MessagePortBase> > ports;
michael@0:   scInfo.mPorts.EnumerateRead(PopulateMessagePortList, &ports);
michael@0:   event->SetPorts(new MessagePortList(static_cast<dom::Event*>(event.get()), ports));
michael@0: 
michael@0:   bool status;
michael@0:   mPort->DispatchEvent(static_cast<dom::Event*>(event.get()), &status);
michael@0:   return status ? NS_OK : NS_ERROR_FAILURE;
michael@0: }
michael@0: 
michael@0: MessagePortBase::MessagePortBase(nsPIDOMWindow* aWindow)
michael@0:   : DOMEventTargetHelper(aWindow)
michael@0: {
michael@0:   // SetIsDOMBinding() is called by DOMEventTargetHelper's ctor.
michael@0: }
michael@0: 
michael@0: MessagePortBase::MessagePortBase()
michael@0: {
michael@0:   SetIsDOMBinding();
michael@0: }
michael@0: 
michael@0: NS_IMPL_CYCLE_COLLECTION_CLASS(MessagePort)
michael@0: 
michael@0: NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(MessagePort,
michael@0:                                                 DOMEventTargetHelper)
michael@0:   NS_IMPL_CYCLE_COLLECTION_UNLINK(mEntangledPort)
michael@0: 
michael@0:   // Custom unlink loop because this array contains nsRunnable objects
michael@0:   // which are not cycle colleactable.
michael@0:   while (!tmp->mMessageQueue.IsEmpty()) {
michael@0:     NS_IMPL_CYCLE_COLLECTION_UNLINK(mMessageQueue[0]->mPort);
michael@0:     NS_IMPL_CYCLE_COLLECTION_UNLINK(mMessageQueue[0]->mSupportsArray);
michael@0:     tmp->mMessageQueue.RemoveElementAt(0);
michael@0:   }
michael@0: 
michael@0:   if (tmp->mDispatchRunnable) {
michael@0:     NS_IMPL_CYCLE_COLLECTION_UNLINK(mDispatchRunnable->mPort);
michael@0:   }
michael@0: 
michael@0: NS_IMPL_CYCLE_COLLECTION_UNLINK_END
michael@0: 
michael@0: NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(MessagePort,
michael@0:                                                   DOMEventTargetHelper)
michael@0:   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mEntangledPort)
michael@0: 
michael@0:   // Custom unlink loop because this array contains nsRunnable objects
michael@0:   // which are not cycle colleactable.
michael@0:   for (uint32_t i = 0, len = tmp->mMessageQueue.Length(); i < len; ++i) {
michael@0:     NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mMessageQueue[i]->mPort);
michael@0:     NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mMessageQueue[i]->mSupportsArray);
michael@0:   }
michael@0: 
michael@0:   if (tmp->mDispatchRunnable) {
michael@0:     NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDispatchRunnable->mPort);
michael@0:   }
michael@0: 
michael@0: NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
michael@0: 
michael@0: NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION_INHERITED(MessagePort)
michael@0: NS_INTERFACE_MAP_END_INHERITING(DOMEventTargetHelper)
michael@0: 
michael@0: NS_IMPL_ADDREF_INHERITED(MessagePort, DOMEventTargetHelper)
michael@0: NS_IMPL_RELEASE_INHERITED(MessagePort, DOMEventTargetHelper)
michael@0: 
michael@0: MessagePort::MessagePort(nsPIDOMWindow* aWindow)
michael@0:   : MessagePortBase(aWindow)
michael@0:   , mMessageQueueEnabled(false)
michael@0: {
michael@0: }
michael@0: 
michael@0: MessagePort::~MessagePort()
michael@0: {
michael@0:   Close();
michael@0: }
michael@0: 
michael@0: JSObject*
michael@0: MessagePort::WrapObject(JSContext* aCx)
michael@0: {
michael@0:   return MessagePortBinding::Wrap(aCx, this);
michael@0: }
michael@0: 
michael@0: void
michael@0: MessagePort::PostMessageMoz(JSContext* aCx, JS::Handle<JS::Value> aMessage,
michael@0:                             const Optional<Sequence<JS::Value>>& aTransferable,
michael@0:                             ErrorResult& aRv)
michael@0: {
michael@0:   nsRefPtr<PostMessageRunnable> event = new PostMessageRunnable();
michael@0: 
michael@0:   // We *must* clone the data here, or the JS::Value could be modified
michael@0:   // by script
michael@0:   StructuredCloneInfo scInfo;
michael@0:   scInfo.mEvent = event;
michael@0:   scInfo.mPort = this;
michael@0: 
michael@0:   JS::Rooted<JS::Value> transferable(aCx, JS::UndefinedValue());
michael@0:   if (aTransferable.WasPassed()) {
michael@0:     const Sequence<JS::Value>& realTransferable = aTransferable.Value();
michael@0: 
michael@0:     // The input sequence only comes from the generated bindings code, which
michael@0:     // ensures it is rooted.
michael@0:     JS::HandleValueArray elements =
michael@0:       JS::HandleValueArray::fromMarkedLocation(realTransferable.Length(),
michael@0:                                                realTransferable.Elements());
michael@0: 
michael@0:     JSObject* array =
michael@0:       JS_NewArrayObject(aCx, elements);
michael@0:     if (!array) {
michael@0:       aRv.Throw(NS_ERROR_OUT_OF_MEMORY);
michael@0:       return;
michael@0:     }
michael@0:     transferable.setObject(*array);
michael@0:   }
michael@0: 
michael@0:   if (!event->Buffer().write(aCx, aMessage, transferable,
michael@0:                              &kPostMessageCallbacks, &scInfo)) {
michael@0:     aRv.Throw(NS_ERROR_DOM_DATA_CLONE_ERR);
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   if (!mEntangledPort) {
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   mEntangledPort->mMessageQueue.AppendElement(event);
michael@0:   mEntangledPort->Dispatch();
michael@0: }
michael@0: 
michael@0: void
michael@0: MessagePort::Start()
michael@0: {
michael@0:   if (mMessageQueueEnabled) {
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   mMessageQueueEnabled = true;
michael@0:   Dispatch();
michael@0: }
michael@0: 
michael@0: void
michael@0: MessagePort::Dispatch()
michael@0: {
michael@0:   if (!mMessageQueueEnabled || mMessageQueue.IsEmpty() || mDispatchRunnable) {
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   nsRefPtr<PostMessageRunnable> event = mMessageQueue.ElementAt(0);
michael@0:   mMessageQueue.RemoveElementAt(0);
michael@0: 
michael@0:   event->Dispatch(this);
michael@0: 
michael@0:   mDispatchRunnable = new DispatchEventRunnable(this);
michael@0:   NS_DispatchToCurrentThread(mDispatchRunnable);
michael@0: }
michael@0: 
michael@0: void
michael@0: MessagePort::Close()
michael@0: {
michael@0:   if (!mEntangledPort) {
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   // This avoids loops.
michael@0:   nsRefPtr<MessagePort> port = mEntangledPort;
michael@0:   mEntangledPort = nullptr;
michael@0: 
michael@0:   // Let's disentangle the 2 ports symmetrically.
michael@0:   port->Close();
michael@0: }
michael@0: 
michael@0: EventHandlerNonNull*
michael@0: MessagePort::GetOnmessage()
michael@0: {
michael@0:   if (NS_IsMainThread()) {
michael@0:     return GetEventHandler(nsGkAtoms::onmessage, EmptyString());
michael@0:   }
michael@0:   return GetEventHandler(nullptr, NS_LITERAL_STRING("message"));
michael@0: }
michael@0: 
michael@0: void
michael@0: MessagePort::SetOnmessage(EventHandlerNonNull* aCallback)
michael@0: {
michael@0:   if (NS_IsMainThread()) {
michael@0:     SetEventHandler(nsGkAtoms::onmessage, EmptyString(), aCallback);
michael@0:   } else {
michael@0:     SetEventHandler(nullptr, NS_LITERAL_STRING("message"), aCallback);
michael@0:   }
michael@0: 
michael@0:   // When using onmessage, the call to start() is implied.
michael@0:   Start();
michael@0: }
michael@0: 
michael@0: void
michael@0: MessagePort::Entangle(MessagePort* aMessagePort)
michael@0: {
michael@0:   MOZ_ASSERT(aMessagePort);
michael@0:   MOZ_ASSERT(aMessagePort != this);
michael@0: 
michael@0:   Close();
michael@0: 
michael@0:   mEntangledPort = aMessagePort;
michael@0: }
michael@0: 
michael@0: already_AddRefed<MessagePortBase>
michael@0: MessagePort::Clone()
michael@0: {
michael@0:   nsRefPtr<MessagePort> newPort = new MessagePort(nullptr);
michael@0: 
michael@0:   // Move all the events in the port message queue of original port.
michael@0:   newPort->mMessageQueue.SwapElements(mMessageQueue);
michael@0: 
michael@0:   if (mEntangledPort) {
michael@0:     nsRefPtr<MessagePort> port = mEntangledPort;
michael@0:     mEntangledPort = nullptr;
michael@0: 
michael@0:     newPort->Entangle(port);
michael@0:     port->Entangle(newPort);
michael@0:   }
michael@0: 
michael@0:   return newPort.forget();
michael@0: }
michael@0: 
michael@0: } // namespace dom
michael@0: } // namespace mozilla