ladybird/AK/Weakable.h

47 lines
775 B
C++

#pragma once
#include "Assertions.h"
#include "Retainable.h"
#include "RetainPtr.h"
namespace AK {
template<typename T> class Weakable;
template<typename T> class WeakPtr;
template<typename T>
class WeakLink : public Retainable<WeakLink<T>> {
friend class Weakable<T>;
public:
T* ptr() { return static_cast<T*>(m_ptr); }
const T* ptr() const { return static_cast<const T*>(m_ptr); }
private:
explicit WeakLink(T& weakable) : m_ptr(&weakable) { }
T* m_ptr;
};
template<typename T>
class Weakable {
private:
class Link;
public:
WeakPtr<T> makeWeakPtr();
protected:
Weakable() { }
~Weakable()
{
if (m_link)
m_link->m_ptr = nullptr;
}
private:
RetainPtr<WeakLink<T>> m_link;
};
}
using AK::Weakable;