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![Andreas Kling](/assets/img/avatar_default.png)
The inode cache was keeping these alive forever. Added a cute little magic trick to Retainable that calls T::one_retain_left() when the retain count is decremented to 1.
73 lines
1.3 KiB
C++
73 lines
1.3 KiB
C++
#pragma once
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#include "Assertions.h"
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#include "StdLibExtras.h"
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namespace AK {
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template<class T>
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constexpr auto call_will_be_destroyed_if_present(T* object) -> decltype(object->will_be_destroyed(), TrueType { })
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{
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object->will_be_destroyed();
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return { };
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}
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constexpr auto call_will_be_destroyed_if_present(...) -> FalseType
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{
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return { };
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}
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template<class T>
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constexpr auto call_one_retain_left_if_present(T* object) -> decltype(object->one_retain_left(), TrueType { })
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{
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object->one_retain_left();
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return { };
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}
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constexpr auto call_one_retain_left_if_present(...) -> FalseType
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{
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return { };
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}
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template<typename T>
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class Retainable {
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public:
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void retain()
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{
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ASSERT(m_retain_count);
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++m_retain_count;
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}
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void release()
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{
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ASSERT(m_retain_count);
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--m_retain_count;
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if (m_retain_count == 0) {
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call_will_be_destroyed_if_present(static_cast<T*>(this));
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delete static_cast<T*>(this);
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} else if (m_retain_count == 1) {
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call_one_retain_left_if_present(static_cast<T*>(this));
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}
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}
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int retain_count() const
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{
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return m_retain_count;
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}
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protected:
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Retainable() { }
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~Retainable()
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{
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ASSERT(!m_retain_count);
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}
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private:
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int m_retain_count { 1 };
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};
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}
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using AK::Retainable;
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