Source/JavaScriptCore/qt/api/qscriptoriginalglobalobject_p.h - platform/external/webkit - Git at Google

 /*
     Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)

     This library is free software; you can redistribute it and/or
     modify it under the terms of the GNU Library General Public
     License as published by the Free Software Foundation; either
     version 2 of the License, or (at your option) any later version.

     This library is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     Library General Public License for more details.

     You should have received a copy of the GNU Library General Public License
     along with this library; see the file COPYING.LIB.  If not, write to
     the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
     Boston, MA 02110-1301, USA.
 */

 #ifndef qscriptoriginalglobalobject_p_h
 #define qscriptoriginalglobalobject_p_h

 #include <JavaScriptCore/JavaScript.h>
 #include <JavaScriptCore/JSRetainPtr.h>
 #include <QtCore/qvector.h>

 /*!
     \internal
     This class is a workaround for missing JSC C API functionality. This class keeps all important
     properties of an original (default) global object, so we can use it even if the global object was
     changed.

     FIXME this class is a container for workarounds :-) it should be replaced by proper JSC C API calls.

     The class have to be created on the QScriptEnginePrivate creation time (before any change got applied to
     global object).
 */
 class QScriptOriginalGlobalObject {
 public:
     inline QScriptOriginalGlobalObject(JSGlobalContextRef context);
     inline ~QScriptOriginalGlobalObject();

     inline bool objectHasOwnProperty(JSObjectRef object, JSStringRef property) const;
     inline QVector<JSStringRef> objectGetOwnPropertyNames(JSObjectRef object) const;

     inline bool isDate(JSValueRef value) const;
     inline bool isArray(JSValueRef value) const;
     inline bool isError(JSValueRef value) const;

     inline JSValueRef functionPrototype() const;
 private:
     inline bool isType(JSValueRef value, JSObjectRef constructor, JSValueRef prototype) const;
     inline void initializeMember(JSObjectRef globalObject, JSStringRef prototypeName, const char* type, JSObjectRef& constructor, JSValueRef& prototype);

     // Copy of the global context reference (the same as in QScriptEnginePrivate).
     JSGlobalContextRef m_context;

     // Copy of constructors and prototypes used in isType functions.
     JSObjectRef m_arrayConstructor;
     JSValueRef m_arrayPrototype;
     JSObjectRef m_errorConstructor;
     JSValueRef m_errorPrototype;
     JSObjectRef m_functionConstructor;
     JSValueRef m_functionPrototype;
     JSObjectRef m_dateConstructor;
     JSValueRef m_datePrototype;

     // Reference to standard JS functions that are not exposed by JSC C API.
     JSObjectRef m_hasOwnPropertyFunction;
     JSObjectRef m_getOwnPropertyNamesFunction;
 };

 QScriptOriginalGlobalObject::QScriptOriginalGlobalObject(JSGlobalContextRef context)
     : m_context(JSGlobalContextRetain(context))
 {
     JSObjectRef globalObject = JSContextGetGlobalObject(m_context);
     JSValueRef exception = 0;
     JSRetainPtr<JSStringRef> propertyName;

     propertyName.adopt(JSStringCreateWithUTF8CString("prototype"));
     initializeMember(globalObject, propertyName.get(), "Array", m_arrayConstructor, m_arrayPrototype);
     initializeMember(globalObject, propertyName.get(), "Error", m_errorConstructor, m_errorPrototype);
     initializeMember(globalObject, propertyName.get(), "Function", m_functionConstructor, m_functionPrototype);
     initializeMember(globalObject, propertyName.get(), "Date", m_dateConstructor, m_datePrototype);

     propertyName.adopt(JSStringCreateWithUTF8CString("hasOwnProperty"));
     m_hasOwnPropertyFunction = const_cast<JSObjectRef>(JSObjectGetProperty(m_context, globalObject, propertyName.get(), &exception));
     JSValueProtect(m_context, m_hasOwnPropertyFunction);
     Q_ASSERT(JSValueIsObject(m_context, m_hasOwnPropertyFunction));
     Q_ASSERT(JSObjectIsFunction(m_context, m_hasOwnPropertyFunction));
     Q_ASSERT(!exception);

     propertyName.adopt(JSStringCreateWithUTF8CString("Object"));
     JSObjectRef objectConstructor
             = const_cast<JSObjectRef>(JSObjectGetProperty(m_context, globalObject, propertyName.get(), &exception));
     propertyName.adopt(JSStringCreateWithUTF8CString("getOwnPropertyNames"));
     m_getOwnPropertyNamesFunction
             = const_cast<JSObjectRef>(JSObjectGetProperty(m_context, objectConstructor, propertyName.get(), &exception));
     JSValueProtect(m_context, m_getOwnPropertyNamesFunction);
     Q_ASSERT(JSValueIsObject(m_context, m_getOwnPropertyNamesFunction));
     Q_ASSERT(JSObjectIsFunction(m_context, m_getOwnPropertyNamesFunction));
     Q_ASSERT(!exception);
 }

 inline void QScriptOriginalGlobalObject::initializeMember(JSObjectRef globalObject, JSStringRef prototypeName, const char* type, JSObjectRef& constructor, JSValueRef& prototype)
 {
     JSRetainPtr<JSStringRef> typeName(Adopt, JSStringCreateWithUTF8CString(type));
     JSValueRef exception = 0;

     // Save references to the Type constructor and prototype.
     JSValueRef typeConstructor = JSObjectGetProperty(m_context, globalObject, typeName.get(), &exception);
     Q_ASSERT(JSValueIsObject(m_context, typeConstructor));
     constructor = JSValueToObject(m_context, typeConstructor, &exception);
     JSValueProtect(m_context, constructor);

     // Note that this is not the [[Prototype]] internal property (which we could
     // get via JSObjectGetPrototype), but the Type.prototype, that will be set
     // as [[Prototype]] of Type instances.
     prototype = JSObjectGetProperty(m_context, constructor, prototypeName, &exception);
     Q_ASSERT(JSValueIsObject(m_context, prototype));
     JSValueProtect(m_context, prototype);
     Q_ASSERT(!exception);
 }

 QScriptOriginalGlobalObject::~QScriptOriginalGlobalObject()
 {
     JSValueUnprotect(m_context, m_arrayConstructor);
     JSValueUnprotect(m_context, m_arrayPrototype);
     JSValueUnprotect(m_context, m_errorConstructor);
     JSValueUnprotect(m_context, m_errorPrototype);
     JSValueUnprotect(m_context, m_functionConstructor);
     JSValueUnprotect(m_context, m_functionPrototype);
     JSValueUnprotect(m_context, m_dateConstructor);
     JSValueUnprotect(m_context, m_datePrototype);
     JSValueUnprotect(m_context, m_hasOwnPropertyFunction);
     JSValueUnprotect(m_context, m_getOwnPropertyNamesFunction);
     JSGlobalContextRelease(m_context);
 }

 inline bool QScriptOriginalGlobalObject::objectHasOwnProperty(JSObjectRef object, JSStringRef property) const
 {
     // FIXME This function should be replaced by JSC C API.
     JSValueRef exception = 0;
     JSValueRef propertyName[] = { JSValueMakeString(m_context, property) };
     JSValueRef result = JSObjectCallAsFunction(m_context, m_hasOwnPropertyFunction, object, 1, propertyName, &exception);
     return exception ? false : JSValueToBoolean(m_context, result);
 }

 /*!
     \internal
     This method gives ownership of all JSStringRefs.
 */
 inline QVector<JSStringRef> QScriptOriginalGlobalObject::objectGetOwnPropertyNames(JSObjectRef object) const
 {
     JSValueRef exception = 0;
     JSObjectRef propertyNames
             = const_cast<JSObjectRef>(JSObjectCallAsFunction(m_context,
                                                             m_getOwnPropertyNamesFunction,
                                                             /* thisObject */ 0,
                                                             /* argumentCount */ 1,
                                                             &object,
                                                             &exception));
     Q_ASSERT(JSValueIsObject(m_context, propertyNames));
     Q_ASSERT(!exception);
     JSStringRef lengthName = QScriptConverter::toString("length");
     int count = JSValueToNumber(m_context, JSObjectGetProperty(m_context, propertyNames, lengthName, &exception), &exception);

     Q_ASSERT(!exception);
     QVector<JSStringRef> names;
     names.reserve(count);
     for (int i = 0; i < count; ++i) {
         JSValueRef tmp = JSObjectGetPropertyAtIndex(m_context, propertyNames, i, &exception);
         names.append(JSValueToStringCopy(m_context, tmp, &exception));
         Q_ASSERT(!exception);
     }
     return names;
 }

 inline bool QScriptOriginalGlobalObject::isDate(JSValueRef value) const
 {
     return isType(value, m_dateConstructor, m_datePrototype);
 }

 inline bool QScriptOriginalGlobalObject::isArray(JSValueRef value) const
 {
     return isType(value, m_arrayConstructor, m_arrayPrototype);
 }

 inline bool QScriptOriginalGlobalObject::isError(JSValueRef value) const
 {
     return isType(value, m_errorConstructor, m_errorPrototype);
 }

 inline JSValueRef QScriptOriginalGlobalObject::functionPrototype() const
 {
     return m_functionPrototype;
 }

 inline bool QScriptOriginalGlobalObject::isType(JSValueRef value, JSObjectRef constructor, JSValueRef prototype) const
 {
     // JSC API doesn't export the [[Class]] information for the builtins. But we know that a value
     // is an object of the Type if it was created with the Type constructor or if it is the Type.prototype.
     JSValueRef exception = 0;
     bool result = JSValueIsInstanceOfConstructor(m_context, value, constructor, &exception) || JSValueIsStrictEqual(m_context, value, prototype);
     Q_ASSERT(!exception);
     return result;
 }

 #endif // qscriptoriginalglobalobject_p_h
	/*
	Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)

	This library is free software; you can redistribute it and/or
	modify it under the terms of the GNU Library General Public
	License as published by the Free Software Foundation; either
	version 2 of the License, or (at your option) any later version.

	This library is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	Library General Public License for more details.

	You should have received a copy of the GNU Library General Public License
	along with this library; see the file COPYING.LIB. If not, write to
	the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
	Boston, MA 02110-1301, USA.
	*/

	#ifndef qscriptoriginalglobalobject_p_h
	#define qscriptoriginalglobalobject_p_h

	#include <JavaScriptCore/JavaScript.h>
	#include <JavaScriptCore/JSRetainPtr.h>
	#include <QtCore/qvector.h>

	/*!
	\internal
	This class is a workaround for missing JSC C API functionality. This class keeps all important
	properties of an original (default) global object, so we can use it even if the global object was
	changed.

	FIXME this class is a container for workarounds :-) it should be replaced by proper JSC C API calls.

	The class have to be created on the QScriptEnginePrivate creation time (before any change got applied to
	global object).
	*/
	class QScriptOriginalGlobalObject {
	public:
	inline QScriptOriginalGlobalObject(JSGlobalContextRef context);
	inline ~QScriptOriginalGlobalObject();

	inline bool objectHasOwnProperty(JSObjectRef object, JSStringRef property) const;
	inline QVector<JSStringRef> objectGetOwnPropertyNames(JSObjectRef object) const;

	inline bool isDate(JSValueRef value) const;
	inline bool isArray(JSValueRef value) const;
	inline bool isError(JSValueRef value) const;

	inline JSValueRef functionPrototype() const;
	private:
	inline bool isType(JSValueRef value, JSObjectRef constructor, JSValueRef prototype) const;
	inline void initializeMember(JSObjectRef globalObject, JSStringRef prototypeName, const char* type, JSObjectRef& constructor, JSValueRef& prototype);

	// Copy of the global context reference (the same as in QScriptEnginePrivate).
	JSGlobalContextRef m_context;

	// Copy of constructors and prototypes used in isType functions.
	JSObjectRef m_arrayConstructor;
	JSValueRef m_arrayPrototype;
	JSObjectRef m_errorConstructor;
	JSValueRef m_errorPrototype;
	JSObjectRef m_functionConstructor;
	JSValueRef m_functionPrototype;
	JSObjectRef m_dateConstructor;
	JSValueRef m_datePrototype;

	// Reference to standard JS functions that are not exposed by JSC C API.
	JSObjectRef m_hasOwnPropertyFunction;
	JSObjectRef m_getOwnPropertyNamesFunction;
	};

	QScriptOriginalGlobalObject::QScriptOriginalGlobalObject(JSGlobalContextRef context)
	: m_context(JSGlobalContextRetain(context))
	{
	JSObjectRef globalObject = JSContextGetGlobalObject(m_context);
	JSValueRef exception = 0;
	JSRetainPtr<JSStringRef> propertyName;

	propertyName.adopt(JSStringCreateWithUTF8CString("prototype"));
	initializeMember(globalObject, propertyName.get(), "Array", m_arrayConstructor, m_arrayPrototype);
	initializeMember(globalObject, propertyName.get(), "Error", m_errorConstructor, m_errorPrototype);
	initializeMember(globalObject, propertyName.get(), "Function", m_functionConstructor, m_functionPrototype);
	initializeMember(globalObject, propertyName.get(), "Date", m_dateConstructor, m_datePrototype);

	propertyName.adopt(JSStringCreateWithUTF8CString("hasOwnProperty"));
	m_hasOwnPropertyFunction = const_cast<JSObjectRef>(JSObjectGetProperty(m_context, globalObject, propertyName.get(), &exception));
	JSValueProtect(m_context, m_hasOwnPropertyFunction);
	Q_ASSERT(JSValueIsObject(m_context, m_hasOwnPropertyFunction));
	Q_ASSERT(JSObjectIsFunction(m_context, m_hasOwnPropertyFunction));
	Q_ASSERT(!exception);

	propertyName.adopt(JSStringCreateWithUTF8CString("Object"));
	JSObjectRef objectConstructor
	= const_cast<JSObjectRef>(JSObjectGetProperty(m_context, globalObject, propertyName.get(), &exception));
	propertyName.adopt(JSStringCreateWithUTF8CString("getOwnPropertyNames"));
	m_getOwnPropertyNamesFunction
	= const_cast<JSObjectRef>(JSObjectGetProperty(m_context, objectConstructor, propertyName.get(), &exception));
	JSValueProtect(m_context, m_getOwnPropertyNamesFunction);
	Q_ASSERT(JSValueIsObject(m_context, m_getOwnPropertyNamesFunction));
	Q_ASSERT(JSObjectIsFunction(m_context, m_getOwnPropertyNamesFunction));
	Q_ASSERT(!exception);
	}

	inline void QScriptOriginalGlobalObject::initializeMember(JSObjectRef globalObject, JSStringRef prototypeName, const char* type, JSObjectRef& constructor, JSValueRef& prototype)
	{
	JSRetainPtr<JSStringRef> typeName(Adopt, JSStringCreateWithUTF8CString(type));
	JSValueRef exception = 0;

	// Save references to the Type constructor and prototype.
	JSValueRef typeConstructor = JSObjectGetProperty(m_context, globalObject, typeName.get(), &exception);
	Q_ASSERT(JSValueIsObject(m_context, typeConstructor));
	constructor = JSValueToObject(m_context, typeConstructor, &exception);
	JSValueProtect(m_context, constructor);

	// Note that this is not the [[Prototype]] internal property (which we could
	// get via JSObjectGetPrototype), but the Type.prototype, that will be set
	// as [[Prototype]] of Type instances.
	prototype = JSObjectGetProperty(m_context, constructor, prototypeName, &exception);
	Q_ASSERT(JSValueIsObject(m_context, prototype));
	JSValueProtect(m_context, prototype);
	Q_ASSERT(!exception);
	}

	QScriptOriginalGlobalObject::~QScriptOriginalGlobalObject()
	{
	JSValueUnprotect(m_context, m_arrayConstructor);
	JSValueUnprotect(m_context, m_arrayPrototype);
	JSValueUnprotect(m_context, m_errorConstructor);
	JSValueUnprotect(m_context, m_errorPrototype);
	JSValueUnprotect(m_context, m_functionConstructor);
	JSValueUnprotect(m_context, m_functionPrototype);
	JSValueUnprotect(m_context, m_dateConstructor);
	JSValueUnprotect(m_context, m_datePrototype);
	JSValueUnprotect(m_context, m_hasOwnPropertyFunction);
	JSValueUnprotect(m_context, m_getOwnPropertyNamesFunction);
	JSGlobalContextRelease(m_context);
	}

	inline bool QScriptOriginalGlobalObject::objectHasOwnProperty(JSObjectRef object, JSStringRef property) const
	{
	// FIXME This function should be replaced by JSC C API.
	JSValueRef exception = 0;
	JSValueRef propertyName[] = { JSValueMakeString(m_context, property) };
	JSValueRef result = JSObjectCallAsFunction(m_context, m_hasOwnPropertyFunction, object, 1, propertyName, &exception);
	return exception ? false : JSValueToBoolean(m_context, result);
	}

	/*!
	\internal
	This method gives ownership of all JSStringRefs.
	*/
	inline QVector<JSStringRef> QScriptOriginalGlobalObject::objectGetOwnPropertyNames(JSObjectRef object) const
	{
	JSValueRef exception = 0;
	JSObjectRef propertyNames
	= const_cast<JSObjectRef>(JSObjectCallAsFunction(m_context,
	m_getOwnPropertyNamesFunction,
	/* thisObject */ 0,
	/* argumentCount */ 1,
	&object,
	&exception));
	Q_ASSERT(JSValueIsObject(m_context, propertyNames));
	Q_ASSERT(!exception);
	JSStringRef lengthName = QScriptConverter::toString("length");
	int count = JSValueToNumber(m_context, JSObjectGetProperty(m_context, propertyNames, lengthName, &exception), &exception);

	Q_ASSERT(!exception);
	QVector<JSStringRef> names;
	names.reserve(count);
	for (int i = 0; i < count; ++i) {
	JSValueRef tmp = JSObjectGetPropertyAtIndex(m_context, propertyNames, i, &exception);
	names.append(JSValueToStringCopy(m_context, tmp, &exception));
	Q_ASSERT(!exception);
	}
	return names;
	}

	inline bool QScriptOriginalGlobalObject::isDate(JSValueRef value) const
	{
	return isType(value, m_dateConstructor, m_datePrototype);
	}

	inline bool QScriptOriginalGlobalObject::isArray(JSValueRef value) const
	{
	return isType(value, m_arrayConstructor, m_arrayPrototype);
	}

	inline bool QScriptOriginalGlobalObject::isError(JSValueRef value) const
	{
	return isType(value, m_errorConstructor, m_errorPrototype);
	}

	inline JSValueRef QScriptOriginalGlobalObject::functionPrototype() const
	{
	return m_functionPrototype;
	}

	inline bool QScriptOriginalGlobalObject::isType(JSValueRef value, JSObjectRef constructor, JSValueRef prototype) const
	{
	// JSC API doesn't export the [[Class]] information for the builtins. But we know that a value
	// is an object of the Type if it was created with the Type constructor or if it is the Type.prototype.
	JSValueRef exception = 0;
	bool result = JSValueIsInstanceOfConstructor(m_context, value, constructor, &exception) \|\| JSValueIsStrictEqual(m_context, value, prototype);
	Q_ASSERT(!exception);
	return result;
	}

	#endif // qscriptoriginalglobalobject_p_h