1 /* 2 * Copyright (C) 2001 Peter Kelly (pmk (at) post.com) 3 * Copyright (C) 2003, 2008, 2009 Apple Inc. All rights reserved. 4 * 5 * This library is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU Lesser General Public 7 * License as published by the Free Software Foundation; either 8 * version 2 of the License, or (at your option) any later version. 9 * 10 * This library is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 * Lesser General Public License for more details. 14 * 15 * You should have received a copy of the GNU Lesser General Public 16 * License along with this library; if not, write to the Free Software 17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 18 */ 19 20 #ifndef JSEventListener_h 21 #define JSEventListener_h 22 23 #include "EventListener.h" 24 #include "JSDOMWindow.h" 25 #include <heap/Weak.h> 26 27 namespace WebCore { 28 29 class JSDOMGlobalObject; 30 31 class JSEventListener : public EventListener { 32 public: 33 static PassRefPtr<JSEventListener> create(JSC::JSObject* listener, JSC::JSObject* wrapper, bool isAttribute, DOMWrapperWorld* isolatedWorld) 34 { 35 return adoptRef(new JSEventListener(listener, wrapper, isAttribute, isolatedWorld)); 36 } 37 38 static const JSEventListener* cast(const EventListener* listener) 39 { 40 return listener->type() == JSEventListenerType 41 ? static_cast<const JSEventListener*>(listener) 42 : 0; 43 } 44 45 virtual ~JSEventListener(); 46 47 virtual bool operator==(const EventListener& other); 48 49 // Returns true if this event listener was created for an event handler attribute, like "onload" or "onclick". 50 bool isAttribute() const { return m_isAttribute; } 51 52 JSC::JSObject* jsFunction(ScriptExecutionContext*) const; 53 DOMWrapperWorld* isolatedWorld() const { return m_isolatedWorld.get(); } 54 55 JSC::JSObject* wrapper() const { return m_wrapper.get(); } 56 void setWrapper(JSC::JSGlobalData& globalData, JSC::JSObject* wrapper) const { m_wrapper.set(globalData, wrapper, 0); } 57 58 private: 59 virtual JSC::JSObject* initializeJSFunction(ScriptExecutionContext*) const; 60 virtual void markJSFunction(JSC::MarkStack&); 61 virtual bool virtualisAttribute() const; 62 63 protected: 64 JSEventListener(JSC::JSObject* function, JSC::JSObject* wrapper, bool isAttribute, DOMWrapperWorld* isolatedWorld); 65 virtual void handleEvent(ScriptExecutionContext*, Event*); 66 67 private: 68 mutable JSC::WriteBarrier<JSC::JSObject> m_jsFunction; 69 mutable JSC::Weak<JSC::JSObject> m_wrapper; 70 71 bool m_isAttribute; 72 RefPtr<DOMWrapperWorld> m_isolatedWorld; 73 }; 74 75 inline JSC::JSObject* JSEventListener::jsFunction(ScriptExecutionContext* scriptExecutionContext) const 76 { 77 if (!m_jsFunction) 78 m_jsFunction.set(*scriptExecutionContext->globalData(), m_wrapper.get(), initializeJSFunction(scriptExecutionContext)); 79 80 // Verify that we have a valid wrapper protecting our function from 81 // garbage collection. 82 ASSERT(m_wrapper || !m_jsFunction); 83 if (!m_wrapper) 84 return 0; 85 86 // Try to verify that m_jsFunction wasn't recycled. (Not exact, since an 87 // event listener can be almost anything, but this makes test-writing easier). 88 ASSERT(!m_jsFunction || static_cast<JSC::JSCell*>(m_jsFunction.get())->isObject()); 89 90 return m_jsFunction.get(); 91 } 92 93 // Creates a JS EventListener for an "onXXX" event attribute. 94 inline PassRefPtr<JSEventListener> createJSAttributeEventListener(JSC::ExecState* exec, JSC::JSValue listener, JSC::JSObject* wrapper) 95 { 96 if (!listener.isObject()) 97 return 0; 98 99 return JSEventListener::create(asObject(listener), wrapper, true, currentWorld(exec)); 100 } 101 102 103 } // namespace WebCore 104 105 #endif // JSEventListener_h 106