| // Experimental shared_ptr with array support -*- C++ -*- |
| |
| // Copyright (C) 2015-2020 Free Software Foundation, Inc. |
| // |
| // This file is part of the GNU ISO C++ Library. This library is free |
| // software; you can redistribute it and/or modify it under the |
| // terms of the GNU General Public License as published by the |
| // Free Software Foundation; either version 3, or (at your option) |
| // any later version. |
| |
| // This library is distributed in the hope that it will be useful, |
| // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| // GNU General Public License for more details. |
| |
| // Under Section 7 of GPL version 3, you are granted additional |
| // permissions described in the GCC Runtime Library Exception, version |
| // 3.1, as published by the Free Software Foundation. |
| |
| // You should have received a copy of the GNU General Public License and |
| // a copy of the GCC Runtime Library Exception along with this program; |
| // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
| // <http://www.gnu.org/licenses/>. |
| |
| /** @file experimental/bits/shared_ptr.h |
| * This is an internal header file, included by other library headers. |
| * Do not attempt to use it directly. @headername{experimental/memory} |
| */ |
| |
| #ifndef _GLIBCXX_EXPERIMENTAL_SHARED_PTR_H |
| #define _GLIBCXX_EXPERIMENTAL_SHARED_PTR_H 1 |
| |
| #pragma GCC system_header |
| |
| #if __cplusplus >= 201402L |
| |
| #include <memory> |
| #include <experimental/type_traits> |
| |
| namespace std _GLIBCXX_VISIBILITY(default) |
| { |
| _GLIBCXX_BEGIN_NAMESPACE_VERSION |
| |
| namespace experimental |
| { |
| inline namespace fundamentals_v2 |
| { |
| // 8.2.1 |
| |
| template<typename _Tp> class shared_ptr; |
| template<typename _Tp> class weak_ptr; |
| template<typename _Tp> class enable_shared_from_this; |
| |
| template<typename _Yp, typename _Tp> |
| constexpr bool __sp_compatible_v |
| = std::__sp_compatible_with<_Yp*, _Tp*>::value; |
| |
| template<typename _Tp, typename _Yp> |
| constexpr bool __sp_is_constructible_v |
| = std::__sp_is_constructible<_Tp, _Yp>::value; |
| |
| template<typename _Tp> |
| class shared_ptr : public __shared_ptr<_Tp> |
| { |
| using _Base_type = __shared_ptr<_Tp>; |
| |
| public: |
| using element_type = typename _Base_type::element_type; |
| |
| private: |
| // Constraint for construction from a pointer of type _Yp*: |
| template<typename _Yp> |
| using _SafeConv = enable_if_t<__sp_is_constructible_v<_Tp, _Yp>>; |
| |
| template<typename _Tp1, typename _Res = void> |
| using _Compatible |
| = enable_if_t<__sp_compatible_v<_Tp1, _Tp>, _Res>; |
| |
| template<typename _Tp1, typename _Del, |
| typename _Ptr = typename unique_ptr<_Tp1, _Del>::pointer, |
| typename _Res = void> |
| using _UniqCompatible = enable_if_t< |
| __sp_compatible_v<_Tp1, _Tp> |
| && experimental::is_convertible_v<_Ptr, element_type*>, |
| _Res>; |
| |
| public: |
| |
| // 8.2.1.1, shared_ptr constructors |
| constexpr shared_ptr() noexcept = default; |
| |
| template<typename _Tp1, typename = _SafeConv<_Tp1>> |
| explicit |
| shared_ptr(_Tp1* __p) : _Base_type(__p) |
| { _M_enable_shared_from_this_with(__p); } |
| |
| template<typename _Tp1, typename _Deleter, typename = _SafeConv<_Tp1>> |
| shared_ptr(_Tp1* __p, _Deleter __d) |
| : _Base_type(__p, __d) |
| { _M_enable_shared_from_this_with(__p); } |
| |
| template<typename _Tp1, typename _Deleter, typename _Alloc, |
| typename = _SafeConv<_Tp1>> |
| shared_ptr(_Tp1* __p, _Deleter __d, _Alloc __a) |
| : _Base_type(__p, __d, __a) |
| { _M_enable_shared_from_this_with(__p); } |
| |
| template<typename _Deleter> |
| shared_ptr(nullptr_t __p, _Deleter __d) |
| : _Base_type(__p, __d) { } |
| |
| template<typename _Deleter, typename _Alloc> |
| shared_ptr(nullptr_t __p, _Deleter __d, _Alloc __a) |
| : _Base_type(__p, __d, __a) { } |
| |
| template<typename _Tp1> |
| shared_ptr(const shared_ptr<_Tp1>& __r, element_type* __p) noexcept |
| : _Base_type(__r, __p) { } |
| |
| shared_ptr(const shared_ptr& __r) noexcept |
| : _Base_type(__r) { } |
| |
| template<typename _Tp1, typename = _Compatible<_Tp1>> |
| shared_ptr(const shared_ptr<_Tp1>& __r) noexcept |
| : _Base_type(__r) { } |
| |
| shared_ptr(shared_ptr&& __r) noexcept |
| : _Base_type(std::move(__r)) { } |
| |
| template<typename _Tp1, typename = _Compatible<_Tp1>> |
| shared_ptr(shared_ptr<_Tp1>&& __r) noexcept |
| : _Base_type(std::move(__r)) { } |
| |
| template<typename _Tp1, typename = _Compatible<_Tp1>> |
| explicit |
| shared_ptr(const weak_ptr<_Tp1>& __r) |
| : _Base_type(__r) { } |
| |
| #if _GLIBCXX_USE_DEPRECATED |
| template<typename _Tp1, typename = _Compatible<_Tp1>> |
| shared_ptr(std::auto_ptr<_Tp1>&& __r) |
| : _Base_type(std::move(__r)) |
| { _M_enable_shared_from_this_with(static_cast<_Tp1*>(this->get())); } |
| #endif |
| |
| template<typename _Tp1, typename _Del, |
| typename = _UniqCompatible<_Tp1, _Del>> |
| shared_ptr(unique_ptr<_Tp1, _Del>&& __r) |
| : _Base_type(std::move(__r)) |
| { |
| // XXX assume conversion from __r.get() to this->get() to __elem_t* |
| // is a round trip, which might not be true in all cases. |
| using __elem_t = typename unique_ptr<_Tp1, _Del>::element_type; |
| _M_enable_shared_from_this_with(static_cast<__elem_t*>(this->get())); |
| } |
| |
| constexpr shared_ptr(nullptr_t __p) |
| : _Base_type(__p) { } |
| |
| // C++14 20.8.2.2 |
| ~shared_ptr() = default; |
| |
| // C++14 20.8.2.3 |
| shared_ptr& operator=(const shared_ptr&) noexcept = default; |
| |
| template <typename _Tp1> |
| _Compatible<_Tp1, shared_ptr&> |
| operator=(const shared_ptr<_Tp1>& __r) noexcept |
| { |
| _Base_type::operator=(__r); |
| return *this; |
| } |
| |
| shared_ptr& |
| operator=(shared_ptr&& __r) noexcept |
| { |
| _Base_type::operator=(std::move(__r)); |
| return *this; |
| } |
| |
| template <typename _Tp1> |
| _Compatible<_Tp1, shared_ptr&> |
| operator=(shared_ptr<_Tp1>&& __r) noexcept |
| { |
| _Base_type::operator=(std::move(__r)); |
| return *this; |
| } |
| |
| #if _GLIBCXX_USE_DEPRECATED |
| template<typename _Tp1> |
| _Compatible<_Tp1, shared_ptr&> |
| operator=(std::auto_ptr<_Tp1>&& __r) |
| { |
| __shared_ptr<_Tp>::operator=(std::move(__r)); |
| return *this; |
| } |
| #endif |
| |
| template <typename _Tp1, typename _Del> |
| _UniqCompatible<_Tp1, _Del, shared_ptr&> |
| operator=(unique_ptr<_Tp1, _Del>&& __r) |
| { |
| _Base_type::operator=(std::move(__r)); |
| return *this; |
| } |
| |
| // C++14 20.8.2.2.4 |
| // swap & reset |
| // 8.2.1.2 shared_ptr observers |
| // in __shared_ptr |
| |
| private: |
| template<typename _Alloc, typename... _Args> |
| shared_ptr(_Sp_make_shared_tag __tag, const _Alloc& __a, |
| _Args&&... __args) |
| : _Base_type(__tag, __a, std::forward<_Args>(__args)...) |
| { _M_enable_shared_from_this_with(this->get()); } |
| |
| template<typename _Tp1, typename _Alloc, typename... _Args> |
| friend shared_ptr<_Tp1> |
| allocate_shared(const _Alloc& __a, _Args&&... __args); |
| |
| shared_ptr(const weak_ptr<_Tp>& __r, std::nothrow_t) |
| : _Base_type(__r, std::nothrow) { } |
| |
| friend class weak_ptr<_Tp>; |
| |
| template<typename _Yp> |
| using __esft_base_t = |
| decltype(__expt_enable_shared_from_this_base(std::declval<_Yp*>())); |
| |
| // Detect an accessible and unambiguous enable_shared_from_this base. |
| template<typename _Yp, typename = void> |
| struct __has_esft_base |
| : false_type { }; |
| |
| template<typename _Yp> |
| struct __has_esft_base<_Yp, __void_t<__esft_base_t<_Yp>>> |
| : __bool_constant<!is_array_v<_Tp>> { }; // ignore base for arrays |
| |
| template<typename _Yp> |
| typename enable_if<__has_esft_base<_Yp>::value>::type |
| _M_enable_shared_from_this_with(const _Yp* __p) noexcept |
| { |
| if (auto __base = __expt_enable_shared_from_this_base(__p)) |
| { |
| __base->_M_weak_this |
| = shared_ptr<_Yp>(*this, const_cast<_Yp*>(__p)); |
| } |
| } |
| |
| template<typename _Yp> |
| typename enable_if<!__has_esft_base<_Yp>::value>::type |
| _M_enable_shared_from_this_with(const _Yp*) noexcept |
| { } |
| }; |
| |
| // C++14 20.8.2.2.7 |
| template<typename _Tp1, typename _Tp2> |
| bool operator==(const shared_ptr<_Tp1>& __a, |
| const shared_ptr<_Tp2>& __b) noexcept |
| { return __a.get() == __b.get(); } |
| |
| template<typename _Tp> |
| inline bool |
| operator==(const shared_ptr<_Tp>& __a, nullptr_t) noexcept |
| { return !__a; } |
| |
| template<typename _Tp> |
| inline bool |
| operator==(nullptr_t, const shared_ptr<_Tp>& __a) noexcept |
| { return !__a; } |
| |
| template<typename _Tp1, typename _Tp2> |
| inline bool |
| operator!=(const shared_ptr<_Tp1>& __a, |
| const shared_ptr<_Tp2>& __b) noexcept |
| { return __a.get() != __b.get(); } |
| |
| template<typename _Tp> |
| inline bool |
| operator!=(const shared_ptr<_Tp>& __a, nullptr_t) noexcept |
| { return (bool)__a; } |
| |
| template<typename _Tp> |
| inline bool |
| operator!=(nullptr_t, const shared_ptr<_Tp>& __a) noexcept |
| { return (bool)__a; } |
| |
| template<typename _Tp1, typename _Tp2> |
| inline bool |
| operator<(const shared_ptr<_Tp1>& __a, |
| const shared_ptr<_Tp2>& __b) noexcept |
| { |
| using __elem_t1 = typename shared_ptr<_Tp1>::element_type; |
| using __elem_t2 = typename shared_ptr<_Tp2>::element_type; |
| using _CT = common_type_t<__elem_t1*, __elem_t2*>; |
| return std::less<_CT>()(__a.get(), __b.get()); |
| } |
| |
| template<typename _Tp> |
| inline bool |
| operator<(const shared_ptr<_Tp>& __a, nullptr_t) noexcept |
| { |
| using __elem_t = typename shared_ptr<_Tp>::element_type; |
| return std::less<__elem_t*>()(__a.get(), nullptr); |
| } |
| |
| template<typename _Tp> |
| inline bool |
| operator<(nullptr_t, const shared_ptr<_Tp>& __a) noexcept |
| { |
| using __elem_t = typename shared_ptr<_Tp>::element_type; |
| return std::less<__elem_t*>()(nullptr, __a.get()); |
| } |
| |
| template<typename _Tp1, typename _Tp2> |
| inline bool |
| operator<=(const shared_ptr<_Tp1>& __a, |
| const shared_ptr<_Tp2>& __b) noexcept |
| { return !(__b < __a); } |
| |
| template<typename _Tp> |
| inline bool |
| operator<=(const shared_ptr<_Tp>& __a, nullptr_t) noexcept |
| { return !(nullptr < __a); } |
| |
| template<typename _Tp> |
| inline bool |
| operator<=(nullptr_t, const shared_ptr<_Tp>& __a) noexcept |
| { return !(__a < nullptr); } |
| |
| template<typename _Tp1, typename _Tp2> |
| inline bool |
| operator>(const shared_ptr<_Tp1>& __a, |
| const shared_ptr<_Tp2>& __b) noexcept |
| { return (__b < __a); } |
| |
| template<typename _Tp> |
| inline bool |
| operator>(const shared_ptr<_Tp>& __a, nullptr_t) noexcept |
| { |
| using __elem_t = typename shared_ptr<_Tp>::element_type; |
| return std::less<__elem_t*>()(nullptr, __a.get()); |
| } |
| |
| template<typename _Tp> |
| inline bool |
| operator>(nullptr_t, const shared_ptr<_Tp>& __a) noexcept |
| { |
| using __elem_t = typename shared_ptr<_Tp>::element_type; |
| return std::less<__elem_t*>()(__a.get(), nullptr); |
| } |
| |
| template<typename _Tp1, typename _Tp2> |
| inline bool |
| operator>=(const shared_ptr<_Tp1>& __a, |
| const shared_ptr<_Tp2>& __b) noexcept |
| { return !(__a < __b); } |
| |
| template<typename _Tp> |
| inline bool |
| operator>=(const shared_ptr<_Tp>& __a, nullptr_t) noexcept |
| { return !(__a < nullptr); } |
| |
| template<typename _Tp> |
| inline bool |
| operator>=(nullptr_t, const shared_ptr<_Tp>& __a) noexcept |
| { return !(nullptr < __a); } |
| |
| // C++14 20.8.2.2.8 |
| template<typename _Tp> |
| inline void |
| swap(shared_ptr<_Tp>& __a, shared_ptr<_Tp>& __b) noexcept |
| { __a.swap(__b); } |
| |
| // 8.2.1.3, shared_ptr casts |
| template<typename _Tp, typename _Tp1> |
| inline shared_ptr<_Tp> |
| static_pointer_cast(const shared_ptr<_Tp1>& __r) noexcept |
| { |
| using __elem_t = typename shared_ptr<_Tp>::element_type; |
| return shared_ptr<_Tp>(__r, static_cast<__elem_t*>(__r.get())); |
| } |
| |
| template<typename _Tp, typename _Tp1> |
| inline shared_ptr<_Tp> |
| dynamic_pointer_cast(const shared_ptr<_Tp1>& __r) noexcept |
| { |
| using __elem_t = typename shared_ptr<_Tp>::element_type; |
| if (_Tp* __p = dynamic_cast<__elem_t*>(__r.get())) |
| return shared_ptr<_Tp>(__r, __p); |
| return shared_ptr<_Tp>(); |
| } |
| |
| template<typename _Tp, typename _Tp1> |
| inline shared_ptr<_Tp> |
| const_pointer_cast(const shared_ptr<_Tp1>& __r) noexcept |
| { |
| using __elem_t = typename shared_ptr<_Tp>::element_type; |
| return shared_ptr<_Tp>(__r, const_cast<__elem_t*>(__r.get())); |
| } |
| |
| template<typename _Tp, typename _Tp1> |
| inline shared_ptr<_Tp> |
| reinterpret_pointer_cast(const shared_ptr<_Tp1>& __r) noexcept |
| { |
| using __elem_t = typename shared_ptr<_Tp>::element_type; |
| return shared_ptr<_Tp>(__r, reinterpret_cast<__elem_t*>(__r.get())); |
| } |
| |
| // C++14 20.8.2.3 |
| template<typename _Tp> |
| class weak_ptr : public __weak_ptr<_Tp> |
| { |
| template<typename _Tp1, typename _Res = void> |
| using _Compatible = enable_if_t<__sp_compatible_v<_Tp1, _Tp>, _Res>; |
| |
| using _Base_type = __weak_ptr<_Tp>; |
| |
| public: |
| constexpr weak_ptr() noexcept = default; |
| |
| template<typename _Tp1, typename = _Compatible<_Tp1>> |
| weak_ptr(const shared_ptr<_Tp1>& __r) noexcept |
| : _Base_type(__r) { } |
| |
| weak_ptr(const weak_ptr&) noexcept = default; |
| |
| template<typename _Tp1, typename = _Compatible<_Tp1>> |
| weak_ptr(const weak_ptr<_Tp1>& __r) noexcept |
| : _Base_type(__r) { } |
| |
| weak_ptr(weak_ptr&&) noexcept = default; |
| |
| template<typename _Tp1, typename = _Compatible<_Tp1>> |
| weak_ptr(weak_ptr<_Tp1>&& __r) noexcept |
| : _Base_type(std::move(__r)) { } |
| |
| weak_ptr& |
| operator=(const weak_ptr& __r) noexcept = default; |
| |
| template<typename _Tp1> |
| _Compatible<_Tp1, weak_ptr&> |
| operator=(const weak_ptr<_Tp1>& __r) noexcept |
| { |
| this->_Base_type::operator=(__r); |
| return *this; |
| } |
| |
| template<typename _Tp1> |
| _Compatible<_Tp1, weak_ptr&> |
| operator=(const shared_ptr<_Tp1>& __r) noexcept |
| { |
| this->_Base_type::operator=(__r); |
| return *this; |
| } |
| |
| weak_ptr& |
| operator=(weak_ptr&& __r) noexcept = default; |
| |
| template<typename _Tp1> |
| _Compatible<_Tp1, weak_ptr&> |
| operator=(weak_ptr<_Tp1>&& __r) noexcept |
| { |
| this->_Base_type::operator=(std::move(__r)); |
| return *this; |
| } |
| |
| shared_ptr<_Tp> |
| lock() const noexcept |
| { return shared_ptr<_Tp>(*this, std::nothrow); } |
| |
| friend class enable_shared_from_this<_Tp>; |
| }; |
| |
| // C++14 20.8.2.3.6 |
| template<typename _Tp> |
| inline void |
| swap(weak_ptr<_Tp>& __a, weak_ptr<_Tp>& __b) noexcept |
| { __a.swap(__b); } |
| |
| /// C++14 20.8.2.2.10 |
| template<typename _Del, typename _Tp> |
| inline _Del* |
| get_deleter(const shared_ptr<_Tp>& __p) noexcept |
| { return std::get_deleter<_Del>(__p); } |
| |
| // C++14 20.8.2.2.11 |
| template<typename _Ch, typename _Tr, typename _Tp> |
| inline std::basic_ostream<_Ch, _Tr>& |
| operator<<(std::basic_ostream<_Ch, _Tr>& __os, const shared_ptr<_Tp>& __p) |
| { |
| __os << __p.get(); |
| return __os; |
| } |
| |
| // C++14 20.8.2.4 |
| template<typename _Tp = void> class owner_less; |
| |
| /// Partial specialization of owner_less for shared_ptr. |
| template<typename _Tp> |
| struct owner_less<shared_ptr<_Tp>> |
| : public _Sp_owner_less<shared_ptr<_Tp>, weak_ptr<_Tp>> |
| { }; |
| |
| /// Partial specialization of owner_less for weak_ptr. |
| template<typename _Tp> |
| struct owner_less<weak_ptr<_Tp>> |
| : public _Sp_owner_less<weak_ptr<_Tp>, shared_ptr<_Tp>> |
| { }; |
| |
| template<> |
| class owner_less<void> |
| { |
| template<typename _Tp, typename _Up> |
| bool |
| operator()(shared_ptr<_Tp> const& __lhs, |
| shared_ptr<_Up> const& __rhs) const |
| { return __lhs.owner_before(__rhs); } |
| |
| template<typename _Tp, typename _Up> |
| bool |
| operator()(shared_ptr<_Tp> const& __lhs, |
| weak_ptr<_Up> const& __rhs) const |
| { return __lhs.owner_before(__rhs); } |
| |
| template<typename _Tp, typename _Up> |
| bool |
| operator()(weak_ptr<_Tp> const& __lhs, |
| shared_ptr<_Up> const& __rhs) const |
| { return __lhs.owner_before(__rhs); } |
| |
| template<typename _Tp, typename _Up> |
| bool |
| operator()(weak_ptr<_Tp> const& __lhs, |
| weak_ptr<_Up> const& __rhs) const |
| { return __lhs.owner_before(__rhs); } |
| |
| typedef void is_transparent; |
| }; |
| |
| // C++14 20.8.2.6 |
| template<typename _Tp> |
| inline bool |
| atomic_is_lock_free(const shared_ptr<_Tp>* __p) |
| { return std::atomic_is_lock_free<_Tp, __default_lock_policy>(__p); } |
| |
| template<typename _Tp> |
| shared_ptr<_Tp> atomic_load(const shared_ptr<_Tp>* __p) |
| { return std::atomic_load<_Tp>(__p); } |
| |
| template<typename _Tp> |
| shared_ptr<_Tp> |
| atomic_load_explicit(const shared_ptr<_Tp>* __p, memory_order __mo) |
| { return std::atomic_load_explicit<_Tp>(__p, __mo); } |
| |
| template<typename _Tp> |
| void atomic_store(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r) |
| { return std::atomic_store<_Tp>(__p, __r); } |
| |
| template<typename _Tp> |
| shared_ptr<_Tp> |
| atomic_store_explicit(const shared_ptr<_Tp>* __p, |
| shared_ptr<_Tp> __r, |
| memory_order __mo) |
| { return std::atomic_store_explicit<_Tp>(__p, __r, __mo); } |
| |
| template<typename _Tp> |
| void atomic_exchange(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r) |
| { return std::atomic_exchange<_Tp>(__p, __r); } |
| |
| template<typename _Tp> |
| shared_ptr<_Tp> |
| atomic_exchange_explicit(const shared_ptr<_Tp>* __p, |
| shared_ptr<_Tp> __r, |
| memory_order __mo) |
| { return std::atomic_exchange_explicit<_Tp>(__p, __r, __mo); } |
| |
| template<typename _Tp> |
| bool atomic_compare_exchange_weak(shared_ptr<_Tp>* __p, |
| shared_ptr<_Tp>* __v, |
| shared_ptr<_Tp> __w) |
| { return std::atomic_compare_exchange_weak<_Tp>(__p, __v, __w); } |
| |
| template<typename _Tp> |
| bool atomic_compare_exchange_strong(shared_ptr<_Tp>* __p, |
| shared_ptr<_Tp>* __v, |
| shared_ptr<_Tp> __w) |
| { return std::atomic_compare_exchange_strong<_Tp>(__p, __v, __w); } |
| |
| template<typename _Tp> |
| bool atomic_compare_exchange_weak_explicit(shared_ptr<_Tp>* __p, |
| shared_ptr<_Tp>* __v, |
| shared_ptr<_Tp> __w, |
| memory_order __success, |
| memory_order __failure) |
| { return std::atomic_compare_exchange_weak_explicit<_Tp>(__p, __v, __w, |
| __success, |
| __failure); } |
| |
| template<typename _Tp> |
| bool atomic_compare_exchange_strong_explicit(shared_ptr<_Tp>* __p, |
| shared_ptr<_Tp>* __v, |
| shared_ptr<_Tp> __w, |
| memory_order __success, |
| memory_order __failure) |
| { return std::atomic_compare_exchange_strong_explicit<_Tp>(__p, __v, __w, |
| __success, |
| __failure); } |
| |
| //enable_shared_from_this |
| template<typename _Tp> |
| class enable_shared_from_this |
| { |
| protected: |
| constexpr enable_shared_from_this() noexcept { } |
| |
| enable_shared_from_this(const enable_shared_from_this&) noexcept { } |
| |
| enable_shared_from_this& |
| operator=(const enable_shared_from_this&) noexcept |
| { return *this; } |
| |
| ~enable_shared_from_this() { } |
| |
| public: |
| shared_ptr<_Tp> |
| shared_from_this() |
| { return shared_ptr<_Tp>(this->_M_weak_this); } |
| |
| shared_ptr<const _Tp> |
| shared_from_this() const |
| { return shared_ptr<const _Tp>(this->_M_weak_this); } |
| |
| weak_ptr<_Tp> |
| weak_from_this() noexcept |
| { return _M_weak_this; } |
| |
| weak_ptr<const _Tp> |
| weak_from_this() const noexcept |
| { return _M_weak_this; } |
| |
| private: |
| template<typename _Tp1> |
| void |
| _M_weak_assign(_Tp1* __p, const __shared_count<>& __n) const noexcept |
| { _M_weak_this._M_assign(__p, __n); } |
| |
| // Found by ADL when this is an associated class. |
| friend const enable_shared_from_this* |
| __expt_enable_shared_from_this_base(const enable_shared_from_this* __p) |
| { return __p; } |
| |
| template<typename> |
| friend class shared_ptr; |
| |
| mutable weak_ptr<_Tp> _M_weak_this; |
| }; |
| } // namespace fundamentals_v2 |
| } // namespace experimental |
| |
| /// std::hash specialization for shared_ptr. |
| template<typename _Tp> |
| struct hash<experimental::shared_ptr<_Tp>> |
| : public __hash_base<size_t, experimental::shared_ptr<_Tp>> |
| { |
| size_t |
| operator()(const experimental::shared_ptr<_Tp>& __s) const noexcept |
| { return std::hash<_Tp*>()(__s.get()); } |
| }; |
| |
| _GLIBCXX_END_NAMESPACE_VERSION |
| } // namespace std |
| |
| #endif // __cplusplus <= 201103L |
| |
| #endif // _GLIBCXX_EXPERIMENTAL_SHARED_PTR_H |