WebCore/bindings/v8/V8LazyEventListener.cpp - WebKit - Git at Google

 /*
  * 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 "config.h"
 #include "V8LazyEventListener.h"

 #include "Frame.h"
 #include "V8Binding.h"
 #include "V8Proxy.h"

 namespace WebCore {

 V8LazyEventListener::V8LazyEventListener(Frame *frame, const String& code, const String& functionName, bool isSVGEvent)
     : V8AbstractEventListener(frame, true)
     , m_code(code)
     , m_functionName(functionName)
     , m_isSVGEvent(isSVGEvent)
     , m_compiled(false)
     , m_wrappedFunctionCompiled(false)
 {
 }

 V8LazyEventListener::~V8LazyEventListener()
 {
     disposeListenerObject();

     // Dispose wrapped function
     if (!m_wrappedFunction.IsEmpty()) {
 #ifndef NDEBUG
         V8GCController::unregisterGlobalHandle(this, m_wrappedFunction);
 #endif
         m_wrappedFunction.Dispose();
         m_wrappedFunction.Clear();
     }
 }

 v8::Local<v8::Function> V8LazyEventListener::getListenerFunction()
 {
     if (m_compiled) {
         ASSERT(m_listener.IsEmpty() || m_listener->IsFunction());
         return m_listener.IsEmpty() ? v8::Local<v8::Function>() : v8::Local<v8::Function>::New(v8::Persistent<v8::Function>::Cast(m_listener));
     }

     m_compiled = true;

     ASSERT(m_frame);

     {
         // Switch to the context of m_frame.
         v8::HandleScope handleScope;

         // Use the outer scope to hold context.
         v8::Handle<v8::Context> v8Context = V8Proxy::context(m_frame);
         // Bail out if we could not get the context.
         if (v8Context.IsEmpty())
             return v8::Local<v8::Function>();

         v8::Context::Scope scope(v8Context);

         // Wrap function around the event code.  The parenthesis around the function are needed so that evaluating the code yields
         // the function value.  Without the parenthesis the function value is thrown away.

         // Make it an anonymous function to avoid name conflict for cases like
         // <body onload='onload()'>
         // <script> function onload() { alert('hi'); } </script>.
         // Set function name to function object instead.
         // See issue 944690.
         //
         // The ECMAScript spec says (very obliquely) that the parameter to an event handler is named "evt".
         //
         // Don't use new lines so that lines in the modified handler
         // have the same numbers as in the original code.
         String code = "(function (evt) {";
         code.append(m_code);
         code.append("\n})");

         v8::Handle<v8::String> codeExternalString = v8ExternalString(code);
         v8::Handle<v8::Script> script = V8Proxy::compileScript(codeExternalString, m_frame->document()->url(), m_lineNumber - 1);
         if (!script.IsEmpty()) {
             V8Proxy* proxy = V8Proxy::retrieve(m_frame);
             ASSERT(proxy);
             v8::Local<v8::Value> value = proxy->runScript(script, false);
             if (!value.IsEmpty()) {
                 ASSERT(value->IsFunction());
                 v8::Local<v8::Function> listenerFunction = v8::Local<v8::Function>::Cast(value);
                 listenerFunction->SetName(v8::String::New(fromWebCoreString(m_functionName), m_functionName.length()));

                 m_listener = v8::Persistent<v8::Function>::New(listenerFunction);
 #ifndef NDEBUG
                 V8GCController::registerGlobalHandle(EVENT_LISTENER, this, m_listener);
 #endif
             }
         }
     }

     ASSERT(m_listener.IsEmpty() || m_listener->IsFunction());
     return m_listener.IsEmpty() ? v8::Local<v8::Function>() : v8::Local<v8::Function>::New(v8::Persistent<v8::Function>::Cast(m_listener));
 }

 v8::Local<v8::Value> V8LazyEventListener::callListenerFunction(v8::Handle<v8::Value> jsEvent, Event* event, bool isWindowEvent)
 {
     v8::Local<v8::Function> handlerFunction = getWrappedListenerFunction();
     v8::Local<v8::Object> receiver = getReceiverObject(event, isWindowEvent);
     if (handlerFunction.IsEmpty() || receiver.IsEmpty())
         return v8::Local<v8::Value>();

     v8::Handle<v8::Value> parameters[1] = { jsEvent };

     V8Proxy* proxy = V8Proxy::retrieve(m_frame);
     return proxy->callFunction(handlerFunction, receiver, 1, parameters);
 }


 static v8::Handle<v8::Value> V8LazyEventListenerToString(const v8::Arguments& args)
 {
     return args.Callee()->GetHiddenValue(v8::String::New("toStringString"));
 }


 v8::Local<v8::Function> V8LazyEventListener::getWrappedListenerFunction()
 {
     if (m_wrappedFunctionCompiled) {
         ASSERT(m_wrappedFunction.IsEmpty() || m_wrappedFunction->IsFunction());
         return m_wrappedFunction.IsEmpty() ? v8::Local<v8::Function>() : v8::Local<v8::Function>::New(m_wrappedFunction);
     }

     m_wrappedFunctionCompiled = true;

     {
         // Switch to the context of m_frame.
         v8::HandleScope handleScope;

         // Use the outer scope to hold context.
         v8::Handle<v8::Context> v8Context = V8Proxy::context(m_frame);
         // Bail out if we cannot get the context.
         if (v8Context.IsEmpty())
             return v8::Local<v8::Function>();

         v8::Context::Scope scope(v8Context);

         // FIXME: cache the wrapper function.

         // Nodes other than the document object, when executing inline event handlers push document, form, 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.
         String code = "(function (evt) {" \
                       "with (this.ownerDocument ? this.ownerDocument : {}) {" \
                       "with (this.form ? this.form : {}) {" \
                       "with (this) {" \
                       "return (function(evt){";
         code.append(m_code);
         // Insert '\n' otherwise //-style comments could break the handler.
         code.append(  "\n}).call(this, evt);}}}})");
         v8::Handle<v8::String> codeExternalString = v8ExternalString(code);
         v8::Handle<v8::Script> script = V8Proxy::compileScript(codeExternalString, m_frame->document()->url(), m_lineNumber);
         if (!script.IsEmpty()) {
             V8Proxy* proxy = V8Proxy::retrieve(m_frame);
             ASSERT(proxy);
             v8::Local<v8::Value> value = proxy->runScript(script, false);
             if (!value.IsEmpty()) {
                 ASSERT(value->IsFunction());

                 m_wrappedFunction = v8::Persistent<v8::Function>::New(v8::Local<v8::Function>::Cast(value));

                 // 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 uses toString on event functions and the evals the source returned (some times a RegExp is applied as
                 // well) for some other use. That fails miserably if the actual wrapper source is returned.
                 v8::Local<v8::FunctionTemplate> toStringTemplate = v8::FunctionTemplate::New(V8LazyEventListenerToString);
                 v8::Local<v8::Function> toStringFunction;
                 if (!toStringTemplate.IsEmpty())
                     toStringFunction = toStringTemplate->GetFunction();
                 if (!toStringFunction.IsEmpty()) {
                     String toStringResult = "function ";
                     toStringResult.append(m_functionName);
                     toStringResult.append("(");
                     if (m_isSVGEvent)
                         toStringResult.append("evt");
                     else
                         toStringResult.append("event");
                     toStringResult.append(") {\n  ");
                     toStringResult.append(m_code);
                     toStringResult.append("\n}");
                     toStringFunction->SetHiddenValue(v8::String::New("toStringString"), v8ExternalString(toStringResult));
                     m_wrappedFunction->Set(v8::String::New("toString"), toStringFunction);
                 }

 #ifndef NDEBUG
                 V8GCController::registerGlobalHandle(EVENT_LISTENER, this, m_wrappedFunction);
 #endif
                 m_wrappedFunction->SetName(v8::String::New(fromWebCoreString(m_functionName), m_functionName.length()));
             }
         }
     }

     return v8::Local<v8::Function>::New(m_wrappedFunction);
 }

 } // namespace WebCore
	/*
	* 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 "config.h"
	#include "V8LazyEventListener.h"

	#include "Frame.h"
	#include "V8Binding.h"
	#include "V8Proxy.h"

	namespace WebCore {

	V8LazyEventListener::V8LazyEventListener(Frame *frame, const String& code, const String& functionName, bool isSVGEvent)
	: V8AbstractEventListener(frame, true)
	, m_code(code)
	, m_functionName(functionName)
	, m_isSVGEvent(isSVGEvent)
	, m_compiled(false)
	, m_wrappedFunctionCompiled(false)
	{
	}

	V8LazyEventListener::~V8LazyEventListener()
	{
	disposeListenerObject();

	// Dispose wrapped function
	if (!m_wrappedFunction.IsEmpty()) {
	#ifndef NDEBUG
	V8GCController::unregisterGlobalHandle(this, m_wrappedFunction);
	#endif
	m_wrappedFunction.Dispose();
	m_wrappedFunction.Clear();
	}
	}

	v8::Local<v8::Function> V8LazyEventListener::getListenerFunction()
	{
	if (m_compiled) {
	ASSERT(m_listener.IsEmpty() \|\| m_listener->IsFunction());
	return m_listener.IsEmpty() ? v8::Local<v8::Function>() : v8::Local<v8::Function>::New(v8::Persistent<v8::Function>::Cast(m_listener));
	}

	m_compiled = true;

	ASSERT(m_frame);

	{
	// Switch to the context of m_frame.
	v8::HandleScope handleScope;

	// Use the outer scope to hold context.
	v8::Handle<v8::Context> v8Context = V8Proxy::context(m_frame);
	// Bail out if we could not get the context.
	if (v8Context.IsEmpty())
	return v8::Local<v8::Function>();

	v8::Context::Scope scope(v8Context);

	// Wrap function around the event code. The parenthesis around the function are needed so that evaluating the code yields
	// the function value. Without the parenthesis the function value is thrown away.

	// Make it an anonymous function to avoid name conflict for cases like
	// <body onload='onload()'>
	// <script> function onload() { alert('hi'); } </script>.
	// Set function name to function object instead.
	// See issue 944690.
	//
	// The ECMAScript spec says (very obliquely) that the parameter to an event handler is named "evt".
	//
	// Don't use new lines so that lines in the modified handler
	// have the same numbers as in the original code.
	String code = "(function (evt) {";
	code.append(m_code);
	code.append("\n})");

	v8::Handle<v8::String> codeExternalString = v8ExternalString(code);
	v8::Handle<v8::Script> script = V8Proxy::compileScript(codeExternalString, m_frame->document()->url(), m_lineNumber - 1);
	if (!script.IsEmpty()) {
	V8Proxy* proxy = V8Proxy::retrieve(m_frame);
	ASSERT(proxy);
	v8::Local<v8::Value> value = proxy->runScript(script, false);
	if (!value.IsEmpty()) {
	ASSERT(value->IsFunction());
	v8::Local<v8::Function> listenerFunction = v8::Local<v8::Function>::Cast(value);
	listenerFunction->SetName(v8::String::New(fromWebCoreString(m_functionName), m_functionName.length()));

	m_listener = v8::Persistent<v8::Function>::New(listenerFunction);
	#ifndef NDEBUG
	V8GCController::registerGlobalHandle(EVENT_LISTENER, this, m_listener);
	#endif
	}
	}
	}

	ASSERT(m_listener.IsEmpty() \|\| m_listener->IsFunction());
	return m_listener.IsEmpty() ? v8::Local<v8::Function>() : v8::Local<v8::Function>::New(v8::Persistent<v8::Function>::Cast(m_listener));
	}

	v8::Local<v8::Value> V8LazyEventListener::callListenerFunction(v8::Handle<v8::Value> jsEvent, Event* event, bool isWindowEvent)
	{
	v8::Local<v8::Function> handlerFunction = getWrappedListenerFunction();
	v8::Local<v8::Object> receiver = getReceiverObject(event, isWindowEvent);
	if (handlerFunction.IsEmpty() \|\| receiver.IsEmpty())
	return v8::Local<v8::Value>();

	v8::Handle<v8::Value> parameters[1] = { jsEvent };

	V8Proxy* proxy = V8Proxy::retrieve(m_frame);
	return proxy->callFunction(handlerFunction, receiver, 1, parameters);
	}


	static v8::Handle<v8::Value> V8LazyEventListenerToString(const v8::Arguments& args)
	{
	return args.Callee()->GetHiddenValue(v8::String::New("toStringString"));
	}


	v8::Local<v8::Function> V8LazyEventListener::getWrappedListenerFunction()
	{
	if (m_wrappedFunctionCompiled) {
	ASSERT(m_wrappedFunction.IsEmpty() \|\| m_wrappedFunction->IsFunction());
	return m_wrappedFunction.IsEmpty() ? v8::Local<v8::Function>() : v8::Local<v8::Function>::New(m_wrappedFunction);
	}

	m_wrappedFunctionCompiled = true;

	{
	// Switch to the context of m_frame.
	v8::HandleScope handleScope;

	// Use the outer scope to hold context.
	v8::Handle<v8::Context> v8Context = V8Proxy::context(m_frame);
	// Bail out if we cannot get the context.
	if (v8Context.IsEmpty())
	return v8::Local<v8::Function>();

	v8::Context::Scope scope(v8Context);

	// FIXME: cache the wrapper function.

	// Nodes other than the document object, when executing inline event handlers push document, form, 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.
	String code = "(function (evt) {" \
	"with (this.ownerDocument ? this.ownerDocument : {}) {" \
	"with (this.form ? this.form : {}) {" \
	"with (this) {" \
	"return (function(evt){";
	code.append(m_code);
	// Insert '\n' otherwise //-style comments could break the handler.
	code.append( "\n}).call(this, evt);}}}})");
	v8::Handle<v8::String> codeExternalString = v8ExternalString(code);
	v8::Handle<v8::Script> script = V8Proxy::compileScript(codeExternalString, m_frame->document()->url(), m_lineNumber);
	if (!script.IsEmpty()) {
	V8Proxy* proxy = V8Proxy::retrieve(m_frame);
	ASSERT(proxy);
	v8::Local<v8::Value> value = proxy->runScript(script, false);
	if (!value.IsEmpty()) {
	ASSERT(value->IsFunction());

	m_wrappedFunction = v8::Persistent<v8::Function>::New(v8::Local<v8::Function>::Cast(value));

	// 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 uses toString on event functions and the evals the source returned (some times a RegExp is applied as
	// well) for some other use. That fails miserably if the actual wrapper source is returned.
	v8::Local<v8::FunctionTemplate> toStringTemplate = v8::FunctionTemplate::New(V8LazyEventListenerToString);
	v8::Local<v8::Function> toStringFunction;
	if (!toStringTemplate.IsEmpty())
	toStringFunction = toStringTemplate->GetFunction();
	if (!toStringFunction.IsEmpty()) {
	String toStringResult = "function ";
	toStringResult.append(m_functionName);
	toStringResult.append("(");
	if (m_isSVGEvent)
	toStringResult.append("evt");
	else
	toStringResult.append("event");
	toStringResult.append(") {\n ");
	toStringResult.append(m_code);
	toStringResult.append("\n}");
	toStringFunction->SetHiddenValue(v8::String::New("toStringString"), v8ExternalString(toStringResult));
	m_wrappedFunction->Set(v8::String::New("toString"), toStringFunction);
	}

	#ifndef NDEBUG
	V8GCController::registerGlobalHandle(EVENT_LISTENER, this, m_wrappedFunction);
	#endif
	m_wrappedFunction->SetName(v8::String::New(fromWebCoreString(m_functionName), m_functionName.length()));
	}
	}
	}

	return v8::Local<v8::Function>::New(m_wrappedFunction);
	}

	} // namespace WebCore