void V8AbstractEventListener::invokeEventHandler(ExecutionContext* context, Event* event, v8::Local<v8::Value> jsEvent)
{
// If jsEvent is empty, attempt to set it as a hidden value would crash v8.
if (jsEvent.IsEmpty())
return;
v8::Local<v8::Context> v8Context = toV8Context(context, world());
if (v8Context.IsEmpty())
return;
// We push the event being processed into the global object, so that it can be exposed by DOMWindow's bindings.
v8::Handle<v8::String> eventSymbol = v8AtomicString(v8Context->GetIsolate(), "event");
v8::Local<v8::Value> returnValue;
{
// Catch exceptions thrown in the event handler so they do not propagate to javascript code that caused the event to fire.
v8::TryCatch tryCatch;
tryCatch.SetVerbose(true);
// Save the old 'event' property so we can restore it later.
v8::Local<v8::Value> savedEvent = getHiddenValue(v8Context->GetIsolate(), v8Context->Global(), eventSymbol);
tryCatch.Reset();
// Make the event available in the global object, so DOMWindow can expose it.
setHiddenValue(v8Context->GetIsolate(), v8Context->Global(), eventSymbol, jsEvent);
tryCatch.Reset();
returnValue = callListenerFunction(context, jsEvent, event);
if (tryCatch.HasCaught())
event->target()->uncaughtExceptionInEventHandler();
if (!tryCatch.CanContinue()) { // Result of TerminateExecution().
if (context->isWorkerGlobalScope())
toWorkerGlobalScope(context)->script()->forbidExecution();
return;
}
tryCatch.Reset();
// Restore the old event. This must be done for all exit paths through this method.
if (savedEvent.IsEmpty())
setHiddenValue(v8Context->GetIsolate(), v8Context->Global(), eventSymbol, v8::Undefined(v8Context->GetIsolate()));
else
setHiddenValue(v8Context->GetIsolate(), v8Context->Global(), eventSymbol, savedEvent);
tryCatch.Reset();
}
ASSERT(!handleOutOfMemory() || returnValue.IsEmpty());
if (returnValue.IsEmpty())
return;
if (!returnValue->IsNull() && !returnValue->IsUndefined() && event->isBeforeUnloadEvent()) {
V8TRYCATCH_FOR_V8STRINGRESOURCE_VOID(V8StringResource<>, stringReturnValue, returnValue);
toBeforeUnloadEvent(event)->setReturnValue(stringReturnValue);
}
if (m_isAttribute && shouldPreventDefault(returnValue))
event->preventDefault();
}
void V8Window::eventAttributeSetterCustom(v8::Local<v8::Value> value, const v8::PropertyCallbackInfo<void>& info)
{
Frame* frame = V8Window::toNative(info.Holder())->frame();
ExceptionState exceptionState(ExceptionState::SetterContext, "event", "Window", info.Holder(), info.GetIsolate());
if (!BindingSecurity::shouldAllowAccessToFrame(info.GetIsolate(), frame, exceptionState)) {
exceptionState.throwIfNeeded();
return;
}
ASSERT(frame);
v8::Local<v8::Context> context = toV8Context(info.GetIsolate(), frame, DOMWrapperWorld::current(info.GetIsolate()));
if (context.IsEmpty())
return;
setHiddenValue(info.GetIsolate(), context->Global(), "event", value);
}
bool setHiddenValue(v8::Isolate* isolate, v8::Handle<v8::Object> object, const char* key, v8::Handle<v8::Value> value)
{
return setHiddenValue(isolate, object, v8AtomicString(isolate, key), value);
}
V8NodeFilterCondition::V8NodeFilterCondition(v8::Handle<v8::Value> filter, v8::Handle<v8::Object> owner, v8::Isolate* isolate)
: m_filter(isolate, filter)
{
setHiddenValue(isolate, owner, "condition", filter);
m_filter.setWeak(this, &setWeakCallback);
}
void V8LazyEventListener::prepareListenerObject(ExecutionContext* context)
{
if (context->isDocument() && !toDocument(context)->allowInlineEventHandlers(m_node, this, m_sourceURL, m_position.m_line)) {
clearListenerObject();
return;
}
if (hasExistingListenerObject())
return;
ASSERT(context->isDocument());
v8::Isolate* isolate = toIsolate(context);
v8::HandleScope handleScope(isolate);
// Use the outer scope to hold context.
v8::Local<v8::Context> v8Context = toV8Context(context, world());
// Bail out if we cannot get the context.
if (v8Context.IsEmpty())
return;
v8::Context::Scope scope(v8Context);
String listenerSource = InspectorInstrumentation::preprocessEventListener(toDocument(context)->frame(), m_code, m_sourceURL, m_functionName);
// FIXME: Remove the following 'with' hack.
//
// Nodes other than the document object, when executing inline event
// handlers push document, form owner, and the target node on the scope chain.
// We do this by using 'with' statement.
// See chrome/fast/forms/form-action.html
// chrome/fast/forms/selected-index-value.html
// base/fast/overflow/onscroll-layer-self-destruct.html
//
// Don't use new lines so that lines in the modified handler
// have the same numbers as in the original code.
// FIXME: V8 does not allow us to programmatically create object environments so
// we have to do this hack! What if m_code escapes to run arbitrary script?
//
// Call with 4 arguments instead of 3, pass additional null as the last parameter.
// By calling the function with 4 arguments, we create a setter on arguments object
// which would shadow property "3" on the prototype.
String code = "(function() {"
"with (this[2]) {"
"with (this[1]) {"
"with (this[0]) {"
"return function(" + m_eventParameterName + ") {" +
listenerSource + "\n" // Insert '\n' otherwise //-style comments could break the handler.
"};"
"}}}})";
v8::Handle<v8::String> codeExternalString = v8String(isolate, code);
v8::Local<v8::Value> result = V8ScriptRunner::compileAndRunInternalScript(codeExternalString, isolate, m_sourceURL, m_position, 0);
if (result.IsEmpty())
return;
// Call the outer function to get the inner function.
ASSERT(result->IsFunction());
v8::Local<v8::Function> intermediateFunction = result.As<v8::Function>();
HTMLFormElement* formElement = 0;
if (m_node && m_node->isHTMLElement())
formElement = toHTMLElement(m_node)->formOwner();
v8::Handle<v8::Object> nodeWrapper = toObjectWrapper<Node>(m_node, isolate);
v8::Handle<v8::Object> formWrapper = toObjectWrapper<HTMLFormElement>(formElement, isolate);
v8::Handle<v8::Object> documentWrapper = toObjectWrapper<Document>(m_node ? m_node->ownerDocument() : 0, isolate);
v8::Local<v8::Object> thisObject = v8::Object::New(isolate);
if (thisObject.IsEmpty())
return;
if (!thisObject->ForceSet(v8::Integer::New(isolate, 0), nodeWrapper))
return;
if (!thisObject->ForceSet(v8::Integer::New(isolate, 1), formWrapper))
return;
if (!thisObject->ForceSet(v8::Integer::New(isolate, 2), documentWrapper))
return;
// FIXME: Remove this code when we stop doing the 'with' hack above.
v8::Local<v8::Value> innerValue = V8ScriptRunner::callInternalFunction(intermediateFunction, thisObject, 0, 0, isolate);
if (innerValue.IsEmpty() || !innerValue->IsFunction())
return;
v8::Local<v8::Function> wrappedFunction = innerValue.As<v8::Function>();
// Change the toString function on the wrapper function to avoid it
// returning the source for the actual wrapper function. Instead it
// returns source for a clean wrapper function with the event
// argument wrapping the event source code. The reason for this is
// that some web sites use toString on event functions and eval the
// source returned (sometimes a RegExp is applied as well) for some
// other use. That fails miserably if the actual wrapper source is
// returned.
v8::Local<v8::Function> toStringFunction = v8::Function::New(isolate, V8LazyEventListenerToString);
ASSERT(!toStringFunction.IsEmpty());
String toStringString = "function " + m_functionName + "(" + m_eventParameterName + ") {\n " + m_code + "\n}";
setHiddenValue(isolate, wrappedFunction, "toStringString", v8String(isolate, toStringString));
wrappedFunction->Set(v8AtomicString(isolate, "toString"), toStringFunction);
wrappedFunction->SetName(v8String(isolate, m_functionName));
// FIXME: Remove the following comment-outs.
// See https://bugs.webkit.org/show_bug.cgi?id=85152 for more details.
//
// For the time being, we comment out the following code since the
// second parsing can happen.
// // Since we only parse once, there's no need to keep data used for parsing around anymore.
// m_functionName = String();
// m_code = String();
// m_eventParameterName = String();
// m_sourceURL = String();
setListenerObject(wrappedFunction);
}
