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rippled/include/xrpl/basics/IntrusivePointer.ipp
Bart 1d42c4f6de refactor: Remove unnecessary copyright notices already covered by LICENSE.md (#5929)
Per XLS-0095, we are taking steps to rename ripple(d) to xrpl(d).

This change specifically removes all copyright notices referencing Ripple, XRPLF, and certain affiliated contributors upon mutual agreement, so the notice in the LICENSE.md file applies throughout. Copyright notices referencing external contributions remain as-is. Duplicate verbiage is also removed.
2025-11-04 08:33:42 +00:00

724 lines
15 KiB
C++

#ifndef XRPL_BASICS_INTRUSIVEPOINTER_IPP_INCLUDED
#define XRPL_BASICS_INTRUSIVEPOINTER_IPP_INCLUDED
#include <xrpl/basics/IntrusivePointer.h>
#include <xrpl/basics/IntrusiveRefCounts.h>
#include <utility>
namespace ripple {
template <class T>
template <CAdoptTag TAdoptTag>
SharedIntrusive<T>::SharedIntrusive(T* p, TAdoptTag) noexcept : ptr_{p}
{
if constexpr (std::is_same_v<
TAdoptTag,
SharedIntrusiveAdoptIncrementStrongTag>)
{
if (p)
p->addStrongRef();
}
}
template <class T>
SharedIntrusive<T>::SharedIntrusive(SharedIntrusive const& rhs)
: ptr_{[&] {
auto p = rhs.unsafeGetRawPtr();
if (p)
p->addStrongRef();
return p;
}()}
{
}
template <class T>
template <class TT>
requires std::convertible_to<TT*, T*>
SharedIntrusive<T>::SharedIntrusive(SharedIntrusive<TT> const& rhs)
: ptr_{[&] {
auto p = rhs.unsafeGetRawPtr();
if (p)
p->addStrongRef();
return p;
}()}
{
}
template <class T>
SharedIntrusive<T>::SharedIntrusive(SharedIntrusive&& rhs)
: ptr_{rhs.unsafeExchange(nullptr)}
{
}
template <class T>
template <class TT>
requires std::convertible_to<TT*, T*>
SharedIntrusive<T>::SharedIntrusive(SharedIntrusive<TT>&& rhs)
: ptr_{rhs.unsafeExchange(nullptr)}
{
}
template <class T>
SharedIntrusive<T>&
SharedIntrusive<T>::operator=(SharedIntrusive const& rhs)
{
if (this == &rhs)
return *this;
auto p = rhs.unsafeGetRawPtr();
if (p)
p->addStrongRef();
unsafeReleaseAndStore(p);
return *this;
}
template <class T>
template <class TT>
// clang-format off
requires std::convertible_to<TT*, T*>
// clang-format on
SharedIntrusive<T>&
SharedIntrusive<T>::operator=(SharedIntrusive<TT> const& rhs)
{
if constexpr (std::is_same_v<T, TT>)
{
// This case should never be hit. The operator above will run instead.
// (The normal operator= is needed or it will be marked `deleted`)
if (this == &rhs)
return *this;
}
auto p = rhs.unsafeGetRawPtr();
if (p)
p->addStrongRef();
unsafeReleaseAndStore(p);
return *this;
}
template <class T>
SharedIntrusive<T>&
SharedIntrusive<T>::operator=(SharedIntrusive&& rhs)
{
if (this == &rhs)
return *this;
unsafeReleaseAndStore(rhs.unsafeExchange(nullptr));
return *this;
}
template <class T>
template <class TT>
// clang-format off
requires std::convertible_to<TT*, T*>
// clang-format on
SharedIntrusive<T>&
SharedIntrusive<T>::operator=(SharedIntrusive<TT>&& rhs)
{
static_assert(
!std::is_same_v<T, TT>,
"This overload should not be instantiated for T == TT");
unsafeReleaseAndStore(rhs.unsafeExchange(nullptr));
return *this;
}
template <class T>
bool
SharedIntrusive<T>::operator!=(std::nullptr_t) const
{
return this->get() != nullptr;
}
template <class T>
bool
SharedIntrusive<T>::operator==(std::nullptr_t) const
{
return this->get() == nullptr;
}
template <class T>
template <CAdoptTag TAdoptTag>
void
SharedIntrusive<T>::adopt(T* p)
{
if constexpr (std::is_same_v<
TAdoptTag,
SharedIntrusiveAdoptIncrementStrongTag>)
{
if (p)
p->addStrongRef();
}
unsafeReleaseAndStore(p);
}
template <class T>
SharedIntrusive<T>::~SharedIntrusive()
{
unsafeReleaseAndStore(nullptr);
};
template <class T>
template <class TT>
SharedIntrusive<T>::SharedIntrusive(
StaticCastTagSharedIntrusive,
SharedIntrusive<TT> const& rhs)
: ptr_{[&] {
auto p = static_cast<T*>(rhs.unsafeGetRawPtr());
if (p)
p->addStrongRef();
return p;
}()}
{
}
template <class T>
template <class TT>
SharedIntrusive<T>::SharedIntrusive(
StaticCastTagSharedIntrusive,
SharedIntrusive<TT>&& rhs)
: ptr_{static_cast<T*>(rhs.unsafeExchange(nullptr))}
{
}
template <class T>
template <class TT>
SharedIntrusive<T>::SharedIntrusive(
DynamicCastTagSharedIntrusive,
SharedIntrusive<TT> const& rhs)
: ptr_{[&] {
auto p = dynamic_cast<T*>(rhs.unsafeGetRawPtr());
if (p)
p->addStrongRef();
return p;
}()}
{
}
template <class T>
template <class TT>
SharedIntrusive<T>::SharedIntrusive(
DynamicCastTagSharedIntrusive,
SharedIntrusive<TT>&& rhs)
{
// This can be simplified without the `exchange`, but the `exchange` is kept
// in anticipation of supporting atomic operations.
auto toSet = rhs.unsafeExchange(nullptr);
if (toSet)
{
ptr_ = dynamic_cast<T*>(toSet);
if (!ptr_)
// need to set the pointer back or will leak
rhs.unsafeExchange(toSet);
}
}
template <class T>
T&
SharedIntrusive<T>::operator*() const noexcept
{
return *unsafeGetRawPtr();
}
template <class T>
T*
SharedIntrusive<T>::operator->() const noexcept
{
return unsafeGetRawPtr();
}
template <class T>
SharedIntrusive<T>::operator bool() const noexcept
{
return bool(unsafeGetRawPtr());
}
template <class T>
void
SharedIntrusive<T>::reset()
{
unsafeReleaseAndStore(nullptr);
}
template <class T>
T*
SharedIntrusive<T>::get() const
{
return unsafeGetRawPtr();
}
template <class T>
std::size_t
SharedIntrusive<T>::use_count() const
{
if (auto p = unsafeGetRawPtr())
return p->use_count();
return 0;
}
template <class T>
T*
SharedIntrusive<T>::unsafeGetRawPtr() const
{
return ptr_;
}
template <class T>
void
SharedIntrusive<T>::unsafeSetRawPtr(T* p)
{
ptr_ = p;
}
template <class T>
T*
SharedIntrusive<T>::unsafeExchange(T* p)
{
return std::exchange(ptr_, p);
}
template <class T>
void
SharedIntrusive<T>::unsafeReleaseAndStore(T* next)
{
auto prev = unsafeExchange(next);
if (!prev)
return;
using enum ReleaseStrongRefAction;
auto action = prev->releaseStrongRef();
switch (action)
{
case noop:
break;
case destroy:
delete prev;
break;
case partialDestroy:
prev->partialDestructor();
partialDestructorFinished(&prev);
// prev is null and may no longer be used
break;
}
}
//------------------------------------------------------------------------------
template <class T>
WeakIntrusive<T>::WeakIntrusive(WeakIntrusive const& rhs) : ptr_{rhs.ptr_}
{
if (ptr_)
ptr_->addWeakRef();
}
template <class T>
WeakIntrusive<T>::WeakIntrusive(WeakIntrusive&& rhs) : ptr_{rhs.ptr_}
{
rhs.ptr_ = nullptr;
}
template <class T>
WeakIntrusive<T>::WeakIntrusive(SharedIntrusive<T> const& rhs)
: ptr_{rhs.unsafeGetRawPtr()}
{
if (ptr_)
ptr_->addWeakRef();
}
template <class T>
template <class TT>
// clang-format off
requires std::convertible_to<TT*, T*>
// clang-format on
WeakIntrusive<T>&
WeakIntrusive<T>::operator=(SharedIntrusive<TT> const& rhs)
{
unsafeReleaseNoStore();
auto p = rhs.unsafeGetRawPtr();
if (p)
p->addWeakRef();
return *this;
}
template <class T>
void
WeakIntrusive<T>::adopt(T* ptr)
{
unsafeReleaseNoStore();
if (ptr)
ptr->addWeakRef();
ptr_ = ptr;
}
template <class T>
WeakIntrusive<T>::~WeakIntrusive()
{
unsafeReleaseNoStore();
}
template <class T>
SharedIntrusive<T>
WeakIntrusive<T>::lock() const
{
if (ptr_ && ptr_->checkoutStrongRefFromWeak())
{
return SharedIntrusive<T>{ptr_, SharedIntrusiveAdoptNoIncrementTag{}};
}
return {};
}
template <class T>
bool
WeakIntrusive<T>::expired() const
{
return (!ptr_ || ptr_->expired());
}
template <class T>
void
WeakIntrusive<T>::reset()
{
unsafeReleaseNoStore();
ptr_ = nullptr;
}
template <class T>
void
WeakIntrusive<T>::unsafeReleaseNoStore()
{
if (!ptr_)
return;
using enum ReleaseWeakRefAction;
auto action = ptr_->releaseWeakRef();
switch (action)
{
case noop:
break;
case destroy:
delete ptr_;
break;
}
}
//------------------------------------------------------------------------------
template <class T>
SharedWeakUnion<T>::SharedWeakUnion(SharedWeakUnion const& rhs) : tp_{rhs.tp_}
{
auto p = rhs.unsafeGetRawPtr();
if (!p)
return;
if (rhs.isStrong())
p->addStrongRef();
else
p->addWeakRef();
}
template <class T>
template <class TT>
requires std::convertible_to<TT*, T*>
SharedWeakUnion<T>::SharedWeakUnion(SharedIntrusive<TT> const& rhs)
{
auto p = rhs.unsafeGetRawPtr();
if (p)
p->addStrongRef();
unsafeSetRawPtr(p, RefStrength::strong);
}
template <class T>
SharedWeakUnion<T>::SharedWeakUnion(SharedWeakUnion&& rhs) : tp_{rhs.tp_}
{
rhs.unsafeSetRawPtr(nullptr);
}
template <class T>
template <class TT>
requires std::convertible_to<TT*, T*>
SharedWeakUnion<T>::SharedWeakUnion(SharedIntrusive<TT>&& rhs)
{
auto p = rhs.unsafeGetRawPtr();
if (p)
unsafeSetRawPtr(p, RefStrength::strong);
rhs.unsafeSetRawPtr(nullptr);
}
template <class T>
SharedWeakUnion<T>&
SharedWeakUnion<T>::operator=(SharedWeakUnion const& rhs)
{
if (this == &rhs)
return *this;
unsafeReleaseNoStore();
if (auto p = rhs.unsafeGetRawPtr())
{
if (rhs.isStrong())
{
p->addStrongRef();
unsafeSetRawPtr(p, RefStrength::strong);
}
else
{
p->addWeakRef();
unsafeSetRawPtr(p, RefStrength::weak);
}
}
else
{
unsafeSetRawPtr(nullptr);
}
return *this;
}
template <class T>
template <class TT>
// clang-format off
requires std::convertible_to<TT*, T*>
// clang-format on
SharedWeakUnion<T>&
SharedWeakUnion<T>::operator=(SharedIntrusive<TT> const& rhs)
{
unsafeReleaseNoStore();
auto p = rhs.unsafeGetRawPtr();
if (p)
p->addStrongRef();
unsafeSetRawPtr(p, RefStrength::strong);
return *this;
}
template <class T>
template <class TT>
// clang-format off
requires std::convertible_to<TT*, T*>
// clang-format on
SharedWeakUnion<T>&
SharedWeakUnion<T>::operator=(SharedIntrusive<TT>&& rhs)
{
unsafeReleaseNoStore();
unsafeSetRawPtr(rhs.unsafeGetRawPtr(), RefStrength::strong);
rhs.unsafeSetRawPtr(nullptr);
return *this;
}
template <class T>
SharedWeakUnion<T>::~SharedWeakUnion()
{
unsafeReleaseNoStore();
};
// Return a strong pointer if this is already a strong pointer (i.e. don't
// lock the weak pointer. Use the `lock` method if that's what's needed)
template <class T>
SharedIntrusive<T>
SharedWeakUnion<T>::getStrong() const
{
SharedIntrusive<T> result;
auto p = unsafeGetRawPtr();
if (p && isStrong())
{
result.template adopt<SharedIntrusiveAdoptIncrementStrongTag>(p);
}
return result;
}
template <class T>
SharedWeakUnion<T>::operator bool() const noexcept
{
return bool(get());
}
template <class T>
void
SharedWeakUnion<T>::reset()
{
unsafeReleaseNoStore();
unsafeSetRawPtr(nullptr);
}
template <class T>
T*
SharedWeakUnion<T>::get() const
{
return isStrong() ? unsafeGetRawPtr() : nullptr;
}
template <class T>
std::size_t
SharedWeakUnion<T>::use_count() const
{
if (auto p = get())
return p->use_count();
return 0;
}
template <class T>
bool
SharedWeakUnion<T>::expired() const
{
auto p = unsafeGetRawPtr();
return (!p || p->expired());
}
template <class T>
SharedIntrusive<T>
SharedWeakUnion<T>::lock() const
{
SharedIntrusive<T> result;
auto p = unsafeGetRawPtr();
if (!p)
return result;
if (isStrong())
{
result.template adopt<SharedIntrusiveAdoptIncrementStrongTag>(p);
return result;
}
if (p->checkoutStrongRefFromWeak())
{
result.template adopt<SharedIntrusiveAdoptNoIncrementTag>(p);
return result;
}
return result;
}
template <class T>
bool
SharedWeakUnion<T>::isStrong() const
{
return !(tp_ & tagMask);
}
template <class T>
bool
SharedWeakUnion<T>::isWeak() const
{
return tp_ & tagMask;
}
template <class T>
bool
SharedWeakUnion<T>::convertToStrong()
{
if (isStrong())
return true;
auto p = unsafeGetRawPtr();
if (p && p->checkoutStrongRefFromWeak())
{
[[maybe_unused]] auto action = p->releaseWeakRef();
XRPL_ASSERT(
(action == ReleaseWeakRefAction::noop),
"ripple::SharedWeakUnion::convertToStrong : "
"action is noop");
unsafeSetRawPtr(p, RefStrength::strong);
return true;
}
return false;
}
template <class T>
bool
SharedWeakUnion<T>::convertToWeak()
{
if (isWeak())
return true;
auto p = unsafeGetRawPtr();
if (!p)
return false;
using enum ReleaseStrongRefAction;
auto action = p->addWeakReleaseStrongRef();
switch (action)
{
case noop:
break;
case destroy:
// We just added a weak ref. How could we destroy?
// LCOV_EXCL_START
UNREACHABLE(
"ripple::SharedWeakUnion::convertToWeak : destroying freshly "
"added ref");
delete p;
unsafeSetRawPtr(nullptr);
return true; // Should never happen
// LCOV_EXCL_STOP
case partialDestroy:
// This is a weird case. We just converted the last strong
// pointer to a weak pointer.
p->partialDestructor();
partialDestructorFinished(&p);
// p is null and may no longer be used
break;
}
unsafeSetRawPtr(p, RefStrength::weak);
return true;
}
template <class T>
T*
SharedWeakUnion<T>::unsafeGetRawPtr() const
{
return reinterpret_cast<T*>(tp_ & ptrMask);
}
template <class T>
void
SharedWeakUnion<T>::unsafeSetRawPtr(T* p, RefStrength rs)
{
tp_ = reinterpret_cast<std::uintptr_t>(p);
if (tp_ && rs == RefStrength::weak)
tp_ |= tagMask;
}
template <class T>
void
SharedWeakUnion<T>::unsafeSetRawPtr(std::nullptr_t)
{
tp_ = 0;
}
template <class T>
void
SharedWeakUnion<T>::unsafeReleaseNoStore()
{
auto p = unsafeGetRawPtr();
if (!p)
return;
if (isStrong())
{
using enum ReleaseStrongRefAction;
auto strongAction = p->releaseStrongRef();
switch (strongAction)
{
case noop:
break;
case destroy:
delete p;
break;
case partialDestroy:
p->partialDestructor();
partialDestructorFinished(&p);
// p is null and may no longer be used
break;
}
}
else
{
using enum ReleaseWeakRefAction;
auto weakAction = p->releaseWeakRef();
switch (weakAction)
{
case noop:
break;
case destroy:
delete p;
break;
}
}
}
} // namespace ripple
#endif