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/*
* Copyright (C) 1999-2001 Harri Porten (porten@kde.org)
* Copyright (C) 2001 Peter Kelly (pmk@post.com)
* Copyright (C) 2003, 2007, 2008 Apple Inc. All rights reserved.
*
* 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.
*
*/
#include "config.h"
#include "JSCell.h"
#include "JSFunction.h"
#include "JSString.h"
#include "JSObject.h"
#include <wtf/MathExtras.h>
namespace JSC {
#if defined NAN && defined INFINITY
extern const double NaN = NAN;
extern const double Inf = INFINITY;
#else // !(defined NAN && defined INFINITY)
// The trick is to define the NaN and Inf globals with a different type than the declaration.
// This trick works because the mangled name of the globals does not include the type, although
// I'm not sure that's guaranteed. There could be alignment issues with this, since arrays of
// characters don't necessarily need the same alignment doubles do, but for now it seems to work.
// It would be good to figure out a 100% clean way that still avoids code that runs at init time.
// Note, we have to use union to ensure alignment. Otherwise, NaN_Bytes can start anywhere,
// while NaN_double has to be 4-byte aligned for 32-bits.
// With -fstrict-aliasing enabled, unions are the only safe way to do type masquerading.
static const union {
struct {
unsigned char NaN_Bytes[8];
unsigned char Inf_Bytes[8];
} bytes;
struct {
double NaN_Double;
double Inf_Double;
} doubles;
} NaNInf = { {
#if CPU(BIG_ENDIAN)
{ 0x7f, 0xf8, 0, 0, 0, 0, 0, 0 },
{ 0x7f, 0xf0, 0, 0, 0, 0, 0, 0 }
#elif CPU(MIDDLE_ENDIAN)
{ 0, 0, 0xf8, 0x7f, 0, 0, 0, 0 },
{ 0, 0, 0xf0, 0x7f, 0, 0, 0, 0 }
#else
{ 0, 0, 0, 0, 0, 0, 0xf8, 0x7f },
{ 0, 0, 0, 0, 0, 0, 0xf0, 0x7f }
#endif
} } ;
extern const double NaN = NaNInf.doubles.NaN_Double;
extern const double Inf = NaNInf.doubles.Inf_Double;
#endif // !(defined NAN && defined INFINITY)
bool JSCell::getUInt32(uint32_t&) const
{
return false;
}
bool JSCell::getString(ExecState* exec, UString&stringValue) const
{
if (!isString())
return false;
stringValue = static_cast<const JSString*>(this)->value(exec);
return true;
}
UString JSCell::getString(ExecState* exec) const
{
return isString() ? static_cast<const JSString*>(this)->value(exec) : UString();
}
JSObject* JSCell::getObject()
{
return isObject() ? asObject(this) : 0;
}
const JSObject* JSCell::getObject() const
{
return isObject() ? static_cast<const JSObject*>(this) : 0;
}
CallType JSCell::getCallData(CallData&)
{
return CallTypeNone;
}
ConstructType JSCell::getConstructData(ConstructData&)
{
return ConstructTypeNone;
}
bool JSCell::getOwnPropertySlot(ExecState* exec, const Identifier& identifier, PropertySlot& slot)
{
// This is not a general purpose implementation of getOwnPropertySlot.
// It should only be called by JSValue::get.
// It calls getPropertySlot, not getOwnPropertySlot.
JSObject* object = toObject(exec);
slot.setBase(object);
if (!object->getPropertySlot(exec, identifier, slot))
slot.setUndefined();
return true;
}
bool JSCell::getOwnPropertySlot(ExecState* exec, unsigned identifier, PropertySlot& slot)
{
// This is not a general purpose implementation of getOwnPropertySlot.
// It should only be called by JSValue::get.
// It calls getPropertySlot, not getOwnPropertySlot.
JSObject* object = toObject(exec);
slot.setBase(object);
if (!object->getPropertySlot(exec, identifier, slot))
slot.setUndefined();
return true;
}
void JSCell::put(ExecState* exec, const Identifier& identifier, JSValue value, PutPropertySlot& slot)
{
toObject(exec)->put(exec, identifier, value, slot);
}
void JSCell::put(ExecState* exec, unsigned identifier, JSValue value)
{
toObject(exec)->put(exec, identifier, value);
}
bool JSCell::deleteProperty(ExecState* exec, const Identifier& identifier)
{
return toObject(exec)->deleteProperty(exec, identifier);
}
bool JSCell::deleteProperty(ExecState* exec, unsigned identifier)
{
return toObject(exec)->deleteProperty(exec, identifier);
}
JSObject* JSCell::toThisObject(ExecState* exec) const
{
return toObject(exec);
}
const ClassInfo* JSCell::classInfo() const
{
return 0;
}
JSValue JSCell::getJSNumber()
{
return JSValue();
}
bool JSCell::isGetterSetter() const
{
return false;
}
JSValue JSCell::toPrimitive(ExecState*, PreferredPrimitiveType) const
{
ASSERT_NOT_REACHED();
return JSValue();
}
bool JSCell::getPrimitiveNumber(ExecState*, double&, JSValue&)
{
ASSERT_NOT_REACHED();
return false;
}
bool JSCell::toBoolean(ExecState*) const
{
ASSERT_NOT_REACHED();
return false;
}
double JSCell::toNumber(ExecState*) const
{
ASSERT_NOT_REACHED();
return 0;
}
UString JSCell::toString(ExecState*) const
{
ASSERT_NOT_REACHED();
return UString();
}
JSObject* JSCell::toObject(ExecState*) const
{
ASSERT_NOT_REACHED();
return 0;
}
} // namespace JSC
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