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: #include "nsJSUtils.h"
michael@0: #include "nsString.h"
michael@0: #include "nsIServiceManager.h"
michael@0: #include "nsIScriptSecurityManager.h"
michael@0: #include "nsIScriptContext.h"
michael@0: #include "nsIScriptGlobalObject.h"
michael@0: #include "nsIXPConnect.h"
michael@0: #include "nsIMutableArray.h"
michael@0: #include "nsVariant.h"
michael@0: #include "nsIDOMBeforeUnloadEvent.h"
michael@0: #include "nsGkAtoms.h"
michael@0: #include "xpcpublic.h"
michael@0: #include "nsJSEnvironment.h"
michael@0: #include "nsDOMJSUtils.h"
michael@0: #include "WorkerPrivate.h"
michael@0: #include "mozilla/ContentEvents.h"
michael@0: #include "mozilla/CycleCollectedJSRuntime.h"
michael@0: #include "mozilla/HoldDropJSObjects.h"
michael@0: #include "mozilla/JSEventHandler.h"
michael@0: #include "mozilla/Likely.h"
michael@0: #include "mozilla/dom/ErrorEvent.h"
michael@0: #include "mozilla/dom/UnionTypes.h"
michael@0: 
michael@0: namespace mozilla {
michael@0: 
michael@0: using namespace dom;
michael@0: 
michael@0: JSEventHandler::JSEventHandler(nsISupports* aTarget,
michael@0:                                nsIAtom* aType,
michael@0:                                const TypedEventHandler& aTypedHandler)
michael@0:   : mEventName(aType)
michael@0:   , mTypedHandler(aTypedHandler)
michael@0: {
michael@0:   nsCOMPtr<nsISupports> base = do_QueryInterface(aTarget);
michael@0:   mTarget = base.get();
michael@0:   // Note, we call HoldJSObjects to get CanSkip called before CC.
michael@0:   HoldJSObjects(this);
michael@0: }
michael@0: 
michael@0: JSEventHandler::~JSEventHandler()
michael@0: {
michael@0:   NS_ASSERTION(!mTarget, "Should have called Disconnect()!");
michael@0:   DropJSObjects(this);
michael@0: }
michael@0: 
michael@0: NS_IMPL_CYCLE_COLLECTION_CLASS(JSEventHandler)
michael@0: 
michael@0: NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(JSEventHandler)
michael@0:   tmp->mTypedHandler.ForgetHandler();
michael@0: NS_IMPL_CYCLE_COLLECTION_UNLINK_END
michael@0: NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INTERNAL(JSEventHandler)
michael@0:   if (MOZ_UNLIKELY(cb.WantDebugInfo()) && tmp->mEventName) {
michael@0:     nsAutoCString name;
michael@0:     name.AppendLiteral("JSEventHandler handlerName=");
michael@0:     name.Append(
michael@0:       NS_ConvertUTF16toUTF8(nsDependentAtomString(tmp->mEventName)).get());
michael@0:     cb.DescribeRefCountedNode(tmp->mRefCnt.get(), name.get());
michael@0:   } else {
michael@0:     NS_IMPL_CYCLE_COLLECTION_DESCRIBE(JSEventHandler, tmp->mRefCnt.get())
michael@0:   }
michael@0:   NS_IMPL_CYCLE_COLLECTION_TRAVERSE_RAWPTR(mTypedHandler.Ptr())
michael@0:   NS_IMPL_CYCLE_COLLECTION_TRAVERSE_SCRIPT_OBJECTS
michael@0: NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
michael@0: 
michael@0: NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_BEGIN(JSEventHandler)
michael@0:   if (tmp->IsBlackForCC()) {
michael@0:     return true;
michael@0:   }
michael@0:   // If we have a target, it is the one which has tmp as onfoo handler.
michael@0:   if (tmp->mTarget) {
michael@0:     nsXPCOMCycleCollectionParticipant* cp = nullptr;
michael@0:     CallQueryInterface(tmp->mTarget, &cp);
michael@0:     nsISupports* canonical = nullptr;
michael@0:     tmp->mTarget->QueryInterface(NS_GET_IID(nsCycleCollectionISupports),
michael@0:                                  reinterpret_cast<void**>(&canonical));
michael@0:     // Usually CanSkip ends up unmarking the event listeners of mTarget,
michael@0:     // so tmp may become black.
michael@0:     if (cp && canonical && cp->CanSkip(canonical, true)) {
michael@0:       return tmp->IsBlackForCC();
michael@0:     }
michael@0:   }
michael@0: NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_END
michael@0: 
michael@0: NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_IN_CC_BEGIN(JSEventHandler)
michael@0:   return tmp->IsBlackForCC();
michael@0: NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_IN_CC_END
michael@0: 
michael@0: NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_THIS_BEGIN(JSEventHandler)
michael@0:   return tmp->IsBlackForCC();
michael@0: NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_THIS_END
michael@0: 
michael@0: NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(JSEventHandler)
michael@0:   NS_INTERFACE_MAP_ENTRY(nsIDOMEventListener)
michael@0:   NS_INTERFACE_MAP_ENTRY(nsISupports)
michael@0:   NS_INTERFACE_MAP_ENTRY(JSEventHandler)
michael@0: NS_INTERFACE_MAP_END
michael@0: 
michael@0: NS_IMPL_CYCLE_COLLECTING_ADDREF(JSEventHandler)
michael@0: NS_IMPL_CYCLE_COLLECTING_RELEASE(JSEventHandler)
michael@0: 
michael@0: bool
michael@0: JSEventHandler::IsBlackForCC()
michael@0: {
michael@0:   // We can claim to be black if all the things we reference are
michael@0:   // effectively black already.
michael@0:   return !mTypedHandler.HasEventHandler() ||
michael@0:          !mTypedHandler.Ptr()->HasGrayCallable();
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: JSEventHandler::HandleEvent(nsIDOMEvent* aEvent)
michael@0: {
michael@0:   nsCOMPtr<EventTarget> target = do_QueryInterface(mTarget);
michael@0:   if (!target || !mTypedHandler.HasEventHandler() ||
michael@0:       !GetTypedEventHandler().Ptr()->CallbackPreserveColor()) {
michael@0:     return NS_ERROR_FAILURE;
michael@0:   }
michael@0: 
michael@0:   Event* event = aEvent->InternalDOMEvent();
michael@0:   bool isMainThread = event->IsMainThreadEvent();
michael@0:   bool isChromeHandler =
michael@0:     isMainThread ?
michael@0:       nsContentUtils::GetObjectPrincipal(
michael@0:         GetTypedEventHandler().Ptr()->CallbackPreserveColor()) ==
michael@0:         nsContentUtils::GetSystemPrincipal() :
michael@0:       mozilla::dom::workers::IsCurrentThreadRunningChromeWorker();
michael@0: 
michael@0:   if (mTypedHandler.Type() == TypedEventHandler::eOnError) {
michael@0:     MOZ_ASSERT_IF(mEventName, mEventName == nsGkAtoms::onerror);
michael@0: 
michael@0:     nsString errorMsg, file;
michael@0:     EventOrString msgOrEvent;
michael@0:     Optional<nsAString> fileName;
michael@0:     Optional<uint32_t> lineNumber;
michael@0:     Optional<uint32_t> columnNumber;
michael@0:     Optional<JS::Handle<JS::Value>> error;
michael@0: 
michael@0:     NS_ENSURE_TRUE(aEvent, NS_ERROR_UNEXPECTED);
michael@0:     ErrorEvent* scriptEvent = aEvent->InternalDOMEvent()->AsErrorEvent();
michael@0:     if (scriptEvent) {
michael@0:       scriptEvent->GetMessage(errorMsg);
michael@0:       msgOrEvent.SetAsString().SetData(errorMsg.Data(), errorMsg.Length());
michael@0: 
michael@0:       scriptEvent->GetFilename(file);
michael@0:       fileName = &file;
michael@0: 
michael@0:       lineNumber.Construct();
michael@0:       lineNumber.Value() = scriptEvent->Lineno();
michael@0: 
michael@0:       columnNumber.Construct();
michael@0:       columnNumber.Value() = scriptEvent->Colno();
michael@0: 
michael@0:       ThreadsafeAutoJSContext cx;
michael@0:       error.Construct(cx);
michael@0:       scriptEvent->GetError(cx, &error.Value());
michael@0:     } else {
michael@0:       msgOrEvent.SetAsEvent() = aEvent->InternalDOMEvent();
michael@0:     }
michael@0: 
michael@0:     nsRefPtr<OnErrorEventHandlerNonNull> handler =
michael@0:       mTypedHandler.OnErrorEventHandler();
michael@0:     ErrorResult rv;
michael@0:     bool handled = handler->Call(mTarget, msgOrEvent, fileName, lineNumber,
michael@0:                                  columnNumber, error, rv);
michael@0:     if (rv.Failed()) {
michael@0:       return rv.ErrorCode();
michael@0:     }
michael@0: 
michael@0:     if (handled) {
michael@0:       event->PreventDefaultInternal(isChromeHandler);
michael@0:     }
michael@0:     return NS_OK;
michael@0:   }
michael@0: 
michael@0:   if (mTypedHandler.Type() == TypedEventHandler::eOnBeforeUnload) {
michael@0:     MOZ_ASSERT(mEventName == nsGkAtoms::onbeforeunload);
michael@0: 
michael@0:     nsRefPtr<OnBeforeUnloadEventHandlerNonNull> handler =
michael@0:       mTypedHandler.OnBeforeUnloadEventHandler();
michael@0:     ErrorResult rv;
michael@0:     nsString retval;
michael@0:     handler->Call(mTarget, *(aEvent->InternalDOMEvent()), retval, rv);
michael@0:     if (rv.Failed()) {
michael@0:       return rv.ErrorCode();
michael@0:     }
michael@0: 
michael@0:     nsCOMPtr<nsIDOMBeforeUnloadEvent> beforeUnload = do_QueryInterface(aEvent);
michael@0:     NS_ENSURE_STATE(beforeUnload);
michael@0: 
michael@0:     if (!DOMStringIsNull(retval)) {
michael@0:       event->PreventDefaultInternal(isChromeHandler);
michael@0: 
michael@0:       nsAutoString text;
michael@0:       beforeUnload->GetReturnValue(text);
michael@0: 
michael@0:       // Set the text in the beforeUnload event as long as it wasn't
michael@0:       // already set (through event.returnValue, which takes
michael@0:       // precedence over a value returned from a JS function in IE)
michael@0:       if (text.IsEmpty()) {
michael@0:         beforeUnload->SetReturnValue(retval);
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     return NS_OK;
michael@0:   }
michael@0: 
michael@0:   MOZ_ASSERT(mTypedHandler.Type() == TypedEventHandler::eNormal);
michael@0:   ErrorResult rv;
michael@0:   nsRefPtr<EventHandlerNonNull> handler = mTypedHandler.NormalEventHandler();
michael@0:   JS::Rooted<JS::Value> retval(CycleCollectedJSRuntime::Get()->Runtime());
michael@0:   handler->Call(mTarget, *(aEvent->InternalDOMEvent()), &retval, rv);
michael@0:   if (rv.Failed()) {
michael@0:     return rv.ErrorCode();
michael@0:   }
michael@0: 
michael@0:   // If the handler returned false and its sense is not reversed,
michael@0:   // or the handler returned true and its sense is reversed from
michael@0:   // the usual (false means cancel), then prevent default.
michael@0:   if (retval.isBoolean() &&
michael@0:       retval.toBoolean() == (mEventName == nsGkAtoms::onerror ||
michael@0:                              mEventName == nsGkAtoms::onmouseover)) {
michael@0:     event->PreventDefaultInternal(isChromeHandler);
michael@0:   }
michael@0: 
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: } // namespace mozilla
michael@0: 
michael@0: using namespace mozilla;
michael@0: 
michael@0: /*
michael@0:  * Factory functions
michael@0:  */
michael@0: 
michael@0: nsresult
michael@0: NS_NewJSEventHandler(nsISupports* aTarget,
michael@0:                      nsIAtom* aEventType,
michael@0:                      const TypedEventHandler& aTypedHandler,
michael@0:                      JSEventHandler** aReturn)
michael@0: {
michael@0:   NS_ENSURE_ARG(aEventType || !NS_IsMainThread());
michael@0:   JSEventHandler* it =
michael@0:     new JSEventHandler(aTarget, aEventType, aTypedHandler);
michael@0:   NS_ADDREF(*aReturn = it);
michael@0: 
michael@0:   return NS_OK;
michael@0: }