mirror of
https://github.com/LadybirdBrowser/ladybird.git
synced 2024-11-25 17:10:23 +00:00
e475263113
Instead of having two separate implementations of AK::RefCounted, one for userspace and one for kernelspace, there is now RefCounted and AtomicRefCounted.
57 lines
1.7 KiB
C++
57 lines
1.7 KiB
C++
/*
|
|
* Copyright (c) 2021, Andreas Kling <kling@serenityos.org>
|
|
*
|
|
* SPDX-License-Identifier: BSD-2-Clause
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include <AK/AtomicRefCounted.h>
|
|
|
|
namespace Kernel {
|
|
|
|
// ListedRefCounted<T> is a slot-in replacement for RefCounted<T> to use in classes
|
|
// that add themselves to a {Spinlock, Mutex}Protected<IntrusiveList> when constructed.
|
|
// The custom unref() implementation here ensures that the list is locked during
|
|
// unref(), and that the T is removed from the list before ~T() is invoked.
|
|
|
|
enum class LockType {
|
|
Spinlock,
|
|
Mutex,
|
|
};
|
|
|
|
template<typename T, LockType Lock>
|
|
class ListedRefCounted : public AtomicRefCountedBase {
|
|
public:
|
|
bool unref() const
|
|
{
|
|
auto* that = const_cast<T*>(static_cast<T const*>(this));
|
|
|
|
auto callback = [&](auto& list) {
|
|
auto new_ref_count = deref_base();
|
|
if (new_ref_count == 0) {
|
|
list.remove(const_cast<T&>(*that));
|
|
if constexpr (requires { that->revoke_weak_ptrs(); }) {
|
|
that->revoke_weak_ptrs();
|
|
}
|
|
if constexpr (requires { that->remove_from_secondary_lists(); })
|
|
that->remove_from_secondary_lists();
|
|
}
|
|
return new_ref_count;
|
|
};
|
|
|
|
RefCountType new_ref_count;
|
|
if constexpr (Lock == LockType::Spinlock)
|
|
new_ref_count = T::all_instances().with(callback);
|
|
else if constexpr (Lock == LockType::Mutex)
|
|
new_ref_count = T::all_instances().with_exclusive(callback);
|
|
if (new_ref_count == 0) {
|
|
if constexpr (requires { that->will_be_destroyed(); })
|
|
that->will_be_destroyed();
|
|
delete that;
|
|
}
|
|
return new_ref_count == 0;
|
|
}
|
|
};
|
|
|
|
}
|