mirror of
https://github.com/SerenityOS/serenity
synced 2024-09-06 08:56:40 +00:00
105 lines
2.8 KiB
C++
105 lines
2.8 KiB
C++
/*
|
|
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions are met:
|
|
*
|
|
* 1. Redistributions of source code must retain the above copyright notice, this
|
|
* list of conditions and the following disclaimer.
|
|
*
|
|
* 2. Redistributions in binary form must reproduce the above copyright notice,
|
|
* this list of conditions and the following disclaimer in the documentation
|
|
* and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
|
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
|
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
|
|
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
|
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include <AK/Assertions.h>
|
|
#include <AK/StdLibExtras.h>
|
|
|
|
namespace AK {
|
|
|
|
template<class T>
|
|
constexpr auto call_will_be_destroyed_if_present(T* object) -> decltype(object->will_be_destroyed(), TrueType {})
|
|
{
|
|
object->will_be_destroyed();
|
|
return {};
|
|
}
|
|
|
|
constexpr auto call_will_be_destroyed_if_present(...) -> FalseType
|
|
{
|
|
return {};
|
|
}
|
|
|
|
template<class T>
|
|
constexpr auto call_one_ref_left_if_present(T* object) -> decltype(object->one_ref_left(), TrueType {})
|
|
{
|
|
object->one_ref_left();
|
|
return {};
|
|
}
|
|
|
|
constexpr auto call_one_ref_left_if_present(...) -> FalseType
|
|
{
|
|
return {};
|
|
}
|
|
|
|
class RefCountedBase {
|
|
public:
|
|
void ref()
|
|
{
|
|
ASSERT(m_ref_count);
|
|
++m_ref_count;
|
|
}
|
|
|
|
int ref_count() const
|
|
{
|
|
return m_ref_count;
|
|
}
|
|
|
|
protected:
|
|
RefCountedBase() {}
|
|
~RefCountedBase()
|
|
{
|
|
ASSERT(!m_ref_count);
|
|
}
|
|
|
|
void deref_base()
|
|
{
|
|
ASSERT(m_ref_count);
|
|
--m_ref_count;
|
|
}
|
|
|
|
int m_ref_count { 1 };
|
|
};
|
|
|
|
template<typename T>
|
|
class RefCounted : public RefCountedBase {
|
|
public:
|
|
void unref()
|
|
{
|
|
deref_base();
|
|
if (m_ref_count == 0) {
|
|
call_will_be_destroyed_if_present(static_cast<T*>(this));
|
|
delete static_cast<T*>(this);
|
|
} else if (m_ref_count == 1) {
|
|
call_one_ref_left_if_present(static_cast<T*>(this));
|
|
}
|
|
}
|
|
};
|
|
|
|
}
|
|
|
|
using AK::RefCounted;
|