#ifndef WeakGCPtr_h
#define WeakGCPtr_h
#include "Collector.h"
#include <wtf/Noncopyable.h>
namespace JSC {
template <typename T> class WeakGCPtr : Noncopyable {
public:
WeakGCPtr() : m_ptr(0) { }
WeakGCPtr(T* ptr) { assign(ptr); }
T* get() const
{
if (!m_ptr || !Heap::isCellMarked(m_ptr))
return 0;
return m_ptr;
}
void clear(JSCell* ptr)
{
if (ptr == m_ptr)
m_ptr = 0;
}
T& operator*() const { return *get(); }
T* operator->() const { return get(); }
bool operator!() const { return !get(); }
#if COMPILER(WINSCW)
operator bool() const { return m_ptr; }
#else
typedef T* WeakGCPtr::*UnspecifiedBoolType;
operator UnspecifiedBoolType() const { return get() ? &WeakGCPtr::m_ptr : 0; }
#endif
WeakGCPtr& operator=(T*);
private:
void assign(T* ptr)
{
if (ptr)
Heap::markCell(ptr);
m_ptr = ptr;
}
T* m_ptr;
};
template <typename T> inline WeakGCPtr<T>& WeakGCPtr<T>::operator=(T* optr)
{
assign(optr);
return *this;
}
template <typename T, typename U> inline bool operator==(const WeakGCPtr<T>& a, const WeakGCPtr<U>& b)
{
return a.get() == b.get();
}
template <typename T, typename U> inline bool operator==(const WeakGCPtr<T>& a, U* b)
{
return a.get() == b;
}
template <typename T, typename U> inline bool operator==(T* a, const WeakGCPtr<U>& b)
{
return a == b.get();
}
template <typename T, typename U> inline bool operator!=(const WeakGCPtr<T>& a, const WeakGCPtr<U>& b)
{
return a.get() != b.get();
}
template <typename T, typename U> inline bool operator!=(const WeakGCPtr<T>& a, U* b)
{
return a.get() != b;
}
template <typename T, typename U> inline bool operator!=(T* a, const WeakGCPtr<U>& b)
{
return a != b.get();
}
template <typename T, typename U> inline WeakGCPtr<T> static_pointer_cast(const WeakGCPtr<U>& p)
{
return WeakGCPtr<T>(static_cast<T*>(p.get()));
}
template <typename T, typename U> inline WeakGCPtr<T> const_pointer_cast(const WeakGCPtr<U>& p)
{
return WeakGCPtr<T>(const_cast<T*>(p.get()));
}
template <typename T> inline T* getPtr(const WeakGCPtr<T>& p)
{
return p.get();
}
}
#endif // WeakGCPtr_h