| /* |
| * Copyright (C) 2006, 2007, 2008, 2009 Google Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * met: |
| * |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following disclaimer |
| * in the documentation and/or other materials provided with the |
| * distribution. |
| * * Neither the name of Google Inc. nor the names of its |
| * contributors may be used to endorse or promote products derived from |
| * this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "third_party/blink/renderer/bindings/core/v8/v8_abstract_event_handler.h" |
| |
| #include "third_party/blink/renderer/bindings/core/v8/v8_binding_for_core.h" |
| #include "third_party/blink/renderer/bindings/core/v8/v8_event.h" |
| #include "third_party/blink/renderer/bindings/core/v8/v8_event_listener_helper.h" |
| #include "third_party/blink/renderer/bindings/core/v8/v8_event_target.h" |
| #include "third_party/blink/renderer/bindings/core/v8/worker_or_worklet_script_controller.h" |
| #include "third_party/blink/renderer/core/dom/document.h" |
| #include "third_party/blink/renderer/core/dom/document_parser.h" |
| #include "third_party/blink/renderer/core/dom/events/event.h" |
| #include "third_party/blink/renderer/core/dom/events/event_target.h" |
| #include "third_party/blink/renderer/core/events/before_unload_event.h" |
| #include "third_party/blink/renderer/core/execution_context/execution_context.h" |
| #include "third_party/blink/renderer/core/probe/core_probes.h" |
| #include "third_party/blink/renderer/core/workers/worker_or_worklet_global_scope.h" |
| #include "third_party/blink/renderer/platform/bindings/v8_private_property.h" |
| #include "third_party/blink/renderer/platform/instance_counters.h" |
| |
| namespace blink { |
| |
| V8AbstractEventHandler::V8AbstractEventHandler(v8::Isolate* isolate, |
| bool is_attribute, |
| DOMWrapperWorld& world) |
| : EventListener(kJSEventHandlerType), |
| is_attribute_(is_attribute), |
| world_(&world), |
| isolate_(isolate) { |
| if (IsMainThread()) { |
| InstanceCounters::IncrementCounter( |
| InstanceCounters::kJSEventListenerCounter); |
| } |
| } |
| |
| V8AbstractEventHandler::~V8AbstractEventHandler() { |
| // For non-main threads a termination garbage collection clears out the |
| // wrapper links to CustomWrappable which result in CustomWrappable not being |
| // rooted by JavaScript objects anymore. This means that |
| // V8AbstractEventHandler can be collected without while still holding a |
| // valid weak references. |
| if (IsMainThread()) { |
| DCHECK(listener_.IsEmpty()); |
| InstanceCounters::DecrementCounter( |
| InstanceCounters::kJSEventListenerCounter); |
| } |
| } |
| |
| // static |
| v8::Local<v8::Value> V8AbstractEventHandler::GetListenerOrNull( |
| v8::Isolate* isolate, |
| EventTarget* event_target, |
| EventListener* listener) { |
| if (listener && listener->GetType() == kJSEventHandlerType) { |
| v8::Local<v8::Object> v8_listener = |
| static_cast<V8AbstractEventHandler*>(listener) |
| ->GetListenerObjectInternal(event_target->GetExecutionContext()); |
| if (!v8_listener.IsEmpty()) |
| return v8_listener; |
| } |
| return v8::Null(isolate); |
| } |
| |
| void V8AbstractEventHandler::handleEvent(ExecutionContext* execution_context, |
| Event* event) { |
| if (!execution_context) |
| return; |
| // Don't reenter V8 if execution was terminated in this instance of V8. |
| if (execution_context->IsJSExecutionForbidden()) |
| return; |
| |
| // A ScriptState used by the event listener needs to be calculated based on |
| // the ExecutionContext that fired the the event listener and the world |
| // that installed the event listener. |
| DCHECK(event); |
| v8::HandleScope handle_scope(ToIsolate(execution_context)); |
| v8::Local<v8::Context> v8_context = ToV8Context(execution_context, World()); |
| if (v8_context.IsEmpty()) |
| return; |
| ScriptState* script_state = ScriptState::From(v8_context); |
| if (!script_state->ContextIsValid()) |
| return; |
| HandleEvent(script_state, event); |
| } |
| |
| void V8AbstractEventHandler::HandleEvent(ScriptState* script_state, |
| Event* event) { |
| ScriptState::Scope scope(script_state); |
| |
| // Get the V8 wrapper for the event object. |
| v8::Local<v8::Value> js_event = |
| ToV8(event, script_state->GetContext()->Global(), GetIsolate()); |
| if (js_event.IsEmpty()) |
| return; |
| InvokeEventHandler(script_state, event, |
| v8::Local<v8::Value>::New(GetIsolate(), js_event)); |
| } |
| |
| void V8AbstractEventHandler::SetListenerObject( |
| ScriptState* script_state, |
| v8::Local<v8::Object> listener, |
| const V8PrivateProperty::Symbol& property) { |
| DCHECK(listener_.IsEmpty()); |
| listener_.Set(GetIsolate(), listener, this, &WrapperCleared); |
| Attach(script_state, listener, property, this); |
| } |
| |
| void V8AbstractEventHandler::InvokeEventHandler(ScriptState* script_state, |
| Event* event, |
| v8::Local<v8::Value> js_event) { |
| if (!event->CanBeDispatchedInWorld(World())) |
| return; |
| |
| v8::Local<v8::Value> return_value; |
| v8::Local<v8::Context> context = script_state->GetContext(); |
| { |
| // Catch exceptions thrown in the event handler so they do not propagate to |
| // javascript code that caused the event to fire. |
| v8::TryCatch try_catch(GetIsolate()); |
| try_catch.SetVerbose(true); |
| |
| v8::Local<v8::Object> global = context->Global(); |
| V8PrivateProperty::Symbol event_symbol = |
| V8PrivateProperty::GetGlobalEvent(GetIsolate()); |
| // Save the old 'event' property so we can restore it later. |
| v8::Local<v8::Value> saved_event; |
| if (!event_symbol.GetOrUndefined(global).ToLocal(&saved_event)) |
| return; |
| try_catch.Reset(); |
| |
| // Expose the event object as |window.event|, except when the event's target |
| // is in a V1 shadow tree, in which case |window.event| should be |
| // |undefined|. |
| Node* target_node = event->target()->ToNode(); |
| if (target_node && target_node->IsInV1ShadowTree()) { |
| event_symbol.Set(global, v8::Undefined(GetIsolate())); |
| } else { |
| event_symbol.Set(global, js_event); |
| } |
| try_catch.Reset(); |
| |
| return_value = CallListenerFunction(script_state, js_event, event); |
| if (try_catch.HasCaught()) |
| event->LegacySetDidListenersThrowFlag(); |
| |
| if (!try_catch.CanContinue()) { // Result of TerminateExecution(). |
| ExecutionContext* execution_context = ToExecutionContext(context); |
| if (auto* scope = |
| DynamicTo<WorkerOrWorkletGlobalScope>(execution_context)) |
| scope->ScriptController()->ForbidExecution(); |
| return; |
| } |
| try_catch.Reset(); |
| |
| // Restore the old event. This must be done for all exit paths through this |
| // method. |
| event_symbol.Set(global, saved_event); |
| try_catch.Reset(); |
| } |
| |
| if (return_value.IsEmpty()) |
| return; |
| |
| // Because OnBeforeUnloadEventHandler is currently not implemented, the |
| // following special handling of BeforeUnloadEvents and events with the type |
| // beforeunload is needed in accordance with the spec at |
| // https://html.spec.whatwg.org/multipage/webappapis.html#the-event-handler-processing-algorithm |
| // TODO(rakina): remove special handling after OnBeforeUnloadEventHandler |
| // is implemented |
| |
| if (!is_attribute_) { |
| return; |
| } |
| |
| if (event->IsBeforeUnloadEvent() && |
| event->type() == EventTypeNames::beforeunload) { |
| if (!return_value->IsUndefined() && !return_value->IsNull()) { |
| event->preventDefault(); |
| if (ToBeforeUnloadEvent(event)->returnValue().IsEmpty()) { |
| TOSTRING_VOID(V8StringResource<>, string_return_value, return_value); |
| ToBeforeUnloadEvent(event)->setReturnValue(string_return_value); |
| } |
| } |
| } else if (ShouldPreventDefault(return_value, event) && |
| event->type() != EventTypeNames::beforeunload) { |
| event->preventDefault(); |
| } |
| } |
| |
| bool V8AbstractEventHandler::ShouldPreventDefault( |
| v8::Local<v8::Value> return_value, |
| Event*) { |
| // Prevent default action if the return value is false in accord with the spec |
| // http://www.w3.org/TR/html5/webappapis.html#event-handler-attributes |
| return return_value->IsBoolean() && !return_value.As<v8::Boolean>()->Value(); |
| } |
| |
| v8::Local<v8::Object> V8AbstractEventHandler::GetReceiverObject( |
| ScriptState* script_state, |
| Event* event) { |
| v8::Local<v8::Object> listener = listener_.NewLocal(GetIsolate()); |
| if (!listener_.IsEmpty() && !listener->IsFunction()) |
| return listener; |
| |
| EventTarget* target = event->currentTarget(); |
| v8::Local<v8::Value> value = |
| ToV8(target, script_state->GetContext()->Global(), GetIsolate()); |
| if (value.IsEmpty()) |
| return v8::Local<v8::Object>(); |
| return v8::Local<v8::Object>::New(GetIsolate(), |
| v8::Local<v8::Object>::Cast(value)); |
| } |
| |
| bool V8AbstractEventHandler::BelongsToTheCurrentWorld( |
| ExecutionContext* execution_context) const { |
| if (!GetIsolate()->GetCurrentContext().IsEmpty() && |
| &World() == &DOMWrapperWorld::Current(GetIsolate())) |
| return true; |
| // If currently parsing, the parser could be accessing this listener |
| // outside of any v8 context; check if it belongs to the main world. |
| if (GetIsolate()->InContext()) |
| return false; |
| auto* document = DynamicTo<Document>(execution_context); |
| if (!document) |
| return false; |
| return document->Parser() && document->Parser()->IsParsing() && |
| World().IsMainWorld(); |
| } |
| |
| void V8AbstractEventHandler::ClearListenerObject() { |
| if (!HasExistingListenerObject()) |
| return; |
| probe::AsyncTaskCanceled(GetIsolate(), this); |
| listener_.Clear(); |
| } |
| |
| void V8AbstractEventHandler::WrapperCleared( |
| const v8::WeakCallbackInfo<V8AbstractEventHandler>& data) { |
| data.GetParameter()->ClearListenerObject(); |
| } |
| |
| void V8AbstractEventHandler::Trace(blink::Visitor* visitor) { |
| visitor->Trace(listener_.Cast<v8::Value>()); |
| EventListener::Trace(visitor); |
| } |
| |
| } // namespace blink |