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#if ISPTR_USE_MODULES
import isptr;
#else
#include <intrusive_shared_ptr/ref_counted.h>
#include <intrusive_shared_ptr/refcnt_ptr.h>
#endif
#include <doctest/doctest.h>
#include <type_traits>
#include <cstdint>
#include <cstddef>
using namespace isptr;
namespace
{
template<class T, class Inner, class Converter>
class ref_counted_delegating_traits;
template<class T, class Inner, class Converter>
struct ref_counted_weak_delegating_traits
{
using strong_value_type = Inner;
using strong_ptr_traits = ref_counted_delegating_traits<T, Inner, Converter>;
static void add_ref(const void * ref) noexcept
{ real_weak_from_delegating_weak(ref)->add_ref(); }
static void sub_ref(const void * ref) noexcept
{ real_weak_from_delegating_weak(ref)->sub_ref(); }
static const Inner * lock(const void * ref) noexcept
{
auto outer_strong = real_weak_from_delegating_weak(ref)->lock_owner();
return outer_strong ? delegating_from_real(outer_strong) : nullptr;
}
static Inner * lock(void * ref) noexcept
{
auto outer_strong = real_weak_from_delegating_weak(ref)->lock_owner();
return outer_strong ? delegating_from_real(outer_strong) : nullptr;
}
private:
static T * real_from_delegating(Inner * pinner)
{ return const_cast<T *>(Converter::real_from_delegating(const_cast<const Inner *>(pinner))); }
static const T * real_from_delegating(const Inner * pinner)
{ return const_cast<const T *>(Converter::real_from_delegating(pinner)); }
static Inner * delegating_from_real(T * pouter)
{ return const_cast<Inner *>(Converter::delegating_from_real(const_cast<const T *>(pouter))); }
static const Inner * delegating_from_real(const T * pouter)
{ return const_cast<const Inner *>(Converter::delegating_from_real(pouter)); }
static typename T::weak_value_type * real_weak_from_delegating_weak(void * ref)
{ return static_cast<typename T::weak_value_type *>(ref); }
static const typename T::weak_value_type * real_weak_from_delegating_weak(const void * ref)
{ return static_cast<const typename T::weak_value_type *>(ref); }
};
template<class T, class Inner, class Converter>
class ref_counted_delegating_traits
{
public:
using weak_value_type = void;
public:
using weak_ptr_traits = std::conditional_t<T::provides_weak_references, ref_counted_weak_delegating_traits<T, Inner, Converter>, void>;
static void add_ref(const Inner * pinner) noexcept
{ real_from_delegating(pinner)->add_ref(); }
static void sub_ref(const Inner * pinner) noexcept
{ real_from_delegating(pinner)->sub_ref(); }
static const void * get_weak_value(const Inner * pinner)
{ return real_from_delegating(pinner)->get_weak_value(); }
static void * get_weak_value(Inner * pinner)
{ return const_cast<void *>(ref_counted_delegating_traits::get_weak_value(const_cast<const Inner *>(pinner))); }
private:
static T * real_from_delegating(Inner * pinner)
{ return const_cast<T *>(Converter::real_from_delegating(const_cast<const Inner *>(pinner))); }
static const T * real_from_delegating(const Inner * pinner)
{ return const_cast<const T *>(Converter::real_from_delegating(pinner)); }
};
template<class T, class Inner, class Converter>
inline
intrusive_shared_ptr<void, ref_counted_weak_delegating_traits<T,Inner, Converter>>
weak_cast(const intrusive_shared_ptr<Inner, ref_counted_delegating_traits<T,Inner, Converter>> & src)
{
using dst_type = intrusive_shared_ptr<void, ref_counted_weak_delegating_traits<T,Inner, Converter>>;
return dst_type::noref(ref_counted_delegating_traits<T,Inner, Converter>::get_weak_value(src.get()));
}
template<class T, class Inner, class Converter>
inline
intrusive_shared_ptr<const void, ref_counted_weak_delegating_traits<T,Inner, Converter>>
weak_cast(const intrusive_shared_ptr<const Inner, ref_counted_delegating_traits<T,Inner, Converter>> & src)
{
using dst_type = intrusive_shared_ptr<const void, ref_counted_weak_delegating_traits<T,Inner, Converter>>;
return dst_type::noref(ref_counted_delegating_traits<T,Inner, Converter>::get_weak_value(src.get()));
}
template<class T, class Inner, class Converter>
inline
intrusive_shared_ptr<Inner, ref_counted_delegating_traits<T,Inner, Converter>>
strong_cast(const intrusive_shared_ptr<void, ref_counted_weak_delegating_traits<T,Inner, Converter>> & src) noexcept
{
using dst_type = intrusive_shared_ptr<Inner, ref_counted_delegating_traits<T,Inner, Converter>>;
return dst_type::noref(ref_counted_weak_delegating_traits<T,Inner, Converter>::lock(src.get()));
}
template<class T, class Inner, class Converter>
inline
intrusive_shared_ptr<const Inner, ref_counted_delegating_traits<T,Inner, Converter>>
strong_cast(const intrusive_shared_ptr<const void, ref_counted_weak_delegating_traits<T,Inner, Converter>> & src) noexcept
{
using dst_type = intrusive_shared_ptr<const Inner, ref_counted_delegating_traits<T,Inner, Converter>>;
return dst_type::noref(ref_counted_weak_delegating_traits<T,Inner, Converter>::lock(src.get()));
}
class outer : public ref_counted<outer>
{
friend ref_counted;
private:
struct inner_converter
{
static const outer * real_from_delegating(const int * pinner) noexcept
{
outer * dummy = nullptr;
size_t distance = (uintptr_t)&(dummy->_inner) - (uintptr_t)dummy;
return (const outer *)((std::byte *)pinner - distance);
//return offsetof(outer, _inner);
}
};
using inner_traits = ref_counted_delegating_traits<outer, int, inner_converter>;
friend ref_counted_delegating_traits<outer, int, inner_converter>;
public:
using inner_ptr = intrusive_shared_ptr<int, inner_traits>;
using const_inner_ptr = intrusive_shared_ptr<const int, inner_traits>;
inner_ptr get_inner_ptr() noexcept
{
return inner_ptr::ref(&_inner);
}
const_inner_ptr get_inner_ptr() const noexcept
{
return const_inner_ptr::ref(&_inner);
}
int & inner()
{ return _inner; }
private:
int _inner = 0;
};
class weak_outer : public ref_counted<weak_outer, ref_counted_flags::provide_weak_references>
{
friend ref_counted;
private:
struct inner_converter
{
static const weak_outer * real_from_delegating(const int * pinner) noexcept
{
weak_outer * dummy = nullptr;
size_t distance = (uintptr_t)&(dummy->_inner) - (uintptr_t)dummy;
return (const weak_outer *)((std::byte *)pinner - distance);
//return offsetof(outer, _inner);
}
static const int * delegating_from_real(const weak_outer * pouter) noexcept
{ return &pouter->_inner; }
};
using inner_traits = ref_counted_delegating_traits<weak_outer, int, inner_converter>;
friend ref_counted_delegating_traits<weak_outer, int, inner_converter>;
public:
using inner_ptr = intrusive_shared_ptr<int, inner_traits>;
using const_inner_ptr = intrusive_shared_ptr<const int, inner_traits>;
using weak_inner_ptr = intrusive_shared_ptr<void, inner_traits::weak_ptr_traits>;
using const_weak_inner_ptr = intrusive_shared_ptr<const void, inner_traits::weak_ptr_traits>;
class weak_value_type : public weak_reference<weak_outer>
{
friend weak_outer;
friend ref_counted_weak_delegating_traits<weak_outer, int, inner_converter>;
private:
weak_value_type(intptr_t count, weak_outer * owner): weak_reference(count, owner)
{};
};
inner_ptr get_inner_ptr() noexcept
{
return inner_ptr::ref(&_inner);
}
const_inner_ptr get_inner_ptr() const noexcept
{
return const_inner_ptr::ref(&_inner);
}
weak_inner_ptr get_weak_inner_ptr()
{
return weak_inner_ptr::noref(inner_traits::get_weak_value(&_inner));
}
const_weak_inner_ptr get_weak_inner_ptr() const
{
return const_weak_inner_ptr::noref(inner_traits::get_weak_value(&_inner));
}
weak_value_type * make_weak_reference(intptr_t count) const
{
return new weak_value_type(count, const_cast<weak_outer *>(this));
}
int & inner()
{ return _inner; }
private:
int _inner = 0;
};
}
TEST_SUITE("inner_ref_counted") {
TEST_CASE( "Inner counting" ) {
auto pouter = refcnt_attach(new outer());
auto pinner = pouter->get_inner_ptr();
CHECK(pinner);
*pinner = 3;
CHECK(pouter->inner() == 3);
}
TEST_CASE( "Weak inner counting" ) {
SUBCASE( "Non const" ) {
auto pouter = refcnt_attach(new weak_outer());
auto pinner1 = pouter->get_inner_ptr();
CHECK(pinner1);
auto weak1 = pouter->get_weak_inner_ptr();
CHECK(weak1);
auto weak2 = weak_cast(pinner1);
CHECK(weak1 == weak2);
auto pinner2 = strong_cast(weak2);
CHECK(pinner2 == pinner1);
}
SUBCASE( "Const" ) {
auto pouter = refcnt_attach(const_cast<const weak_outer *>(new weak_outer()));
auto pinner1 = pouter->get_inner_ptr();
CHECK(pinner1);
auto weak1 = pouter->get_weak_inner_ptr();
CHECK(weak1);
auto weak2 = weak_cast(pinner1);
CHECK(weak1 == weak2);
auto pinner2 = strong_cast(weak2);
CHECK(pinner2 == pinner1);
}
}
}
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