libcxx/include/__memory/shared_ptr.h
2023-10-03 17:20:52 -07:00

2009 lines
60 KiB
C++

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___MEMORY_SHARED_PTR_H
#define _LIBCPP___MEMORY_SHARED_PTR_H
#include <__availability>
#include <__compare/compare_three_way.h>
#include <__compare/ordering.h>
#include <__config>
#include <__functional/binary_function.h>
#include <__functional/operations.h>
#include <__functional/reference_wrapper.h>
#include <__iterator/access.h>
#include <__memory/addressof.h>
#include <__memory/allocation_guard.h>
#include <__memory/allocator.h>
#include <__memory/allocator_destructor.h>
#include <__memory/allocator_traits.h>
#include <__memory/auto_ptr.h>
#include <__memory/compressed_pair.h>
#include <__memory/construct_at.h>
#include <__memory/pointer_traits.h>
#include <__memory/uninitialized_algorithms.h>
#include <__memory/unique_ptr.h>
#include <__utility/forward.h>
#include <__utility/move.h>
#include <__utility/swap.h>
#include <cstddef>
#include <cstdlib> // abort
#include <iosfwd>
#include <new>
#include <stdexcept>
#include <typeinfo>
#if !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
# include <atomic>
#endif
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
// NOTE: Relaxed and acq/rel atomics (for increment and decrement respectively)
// should be sufficient for thread safety.
// See https://llvm.org/PR22803
#if defined(__clang__) && __has_builtin(__atomic_add_fetch) \
&& defined(__ATOMIC_RELAXED) \
&& defined(__ATOMIC_ACQ_REL)
# define _LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT
#elif defined(_LIBCPP_COMPILER_GCC)
# define _LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT
#endif
template <class _ValueType>
inline _LIBCPP_INLINE_VISIBILITY
_ValueType __libcpp_relaxed_load(_ValueType const* __value) {
#if !defined(_LIBCPP_HAS_NO_THREADS) && \
defined(__ATOMIC_RELAXED) && \
(__has_builtin(__atomic_load_n) || defined(_LIBCPP_COMPILER_GCC))
return __atomic_load_n(__value, __ATOMIC_RELAXED);
#else
return *__value;
#endif
}
template <class _ValueType>
inline _LIBCPP_INLINE_VISIBILITY
_ValueType __libcpp_acquire_load(_ValueType const* __value) {
#if !defined(_LIBCPP_HAS_NO_THREADS) && \
defined(__ATOMIC_ACQUIRE) && \
(__has_builtin(__atomic_load_n) || defined(_LIBCPP_COMPILER_GCC))
return __atomic_load_n(__value, __ATOMIC_ACQUIRE);
#else
return *__value;
#endif
}
template <class _Tp>
inline _LIBCPP_INLINE_VISIBILITY _Tp
__libcpp_atomic_refcount_increment(_Tp& __t) _NOEXCEPT
{
#if defined(_LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT) && !defined(_LIBCPP_HAS_NO_THREADS)
return __atomic_add_fetch(&__t, 1, __ATOMIC_RELAXED);
#else
return __t += 1;
#endif
}
template <class _Tp>
inline _LIBCPP_INLINE_VISIBILITY _Tp
__libcpp_atomic_refcount_decrement(_Tp& __t) _NOEXCEPT
{
#if defined(_LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT) && !defined(_LIBCPP_HAS_NO_THREADS)
return __atomic_add_fetch(&__t, -1, __ATOMIC_ACQ_REL);
#else
return __t -= 1;
#endif
}
class _LIBCPP_EXCEPTION_ABI bad_weak_ptr
: public std::exception
{
public:
bad_weak_ptr() _NOEXCEPT = default;
bad_weak_ptr(const bad_weak_ptr&) _NOEXCEPT = default;
~bad_weak_ptr() _NOEXCEPT override;
const char* what() const _NOEXCEPT override;
};
_LIBCPP_NORETURN inline _LIBCPP_INLINE_VISIBILITY
void __throw_bad_weak_ptr()
{
#ifndef _LIBCPP_NO_EXCEPTIONS
throw bad_weak_ptr();
#else
_VSTD::abort();
#endif
}
template<class _Tp> class _LIBCPP_TEMPLATE_VIS weak_ptr;
class _LIBCPP_TYPE_VIS __shared_count
{
__shared_count(const __shared_count&);
__shared_count& operator=(const __shared_count&);
protected:
long __shared_owners_;
virtual ~__shared_count();
private:
virtual void __on_zero_shared() _NOEXCEPT = 0;
public:
_LIBCPP_INLINE_VISIBILITY
explicit __shared_count(long __refs = 0) _NOEXCEPT
: __shared_owners_(__refs) {}
#if defined(_LIBCPP_SHARED_PTR_DEFINE_LEGACY_INLINE_FUNCTIONS)
void __add_shared() noexcept;
bool __release_shared() noexcept;
#else
_LIBCPP_INLINE_VISIBILITY
void __add_shared() _NOEXCEPT {
__libcpp_atomic_refcount_increment(__shared_owners_);
}
_LIBCPP_INLINE_VISIBILITY
bool __release_shared() _NOEXCEPT {
if (__libcpp_atomic_refcount_decrement(__shared_owners_) == -1) {
__on_zero_shared();
return true;
}
return false;
}
#endif
_LIBCPP_INLINE_VISIBILITY
long use_count() const _NOEXCEPT {
return __libcpp_relaxed_load(&__shared_owners_) + 1;
}
};
class _LIBCPP_TYPE_VIS __shared_weak_count
: private __shared_count
{
long __shared_weak_owners_;
public:
_LIBCPP_INLINE_VISIBILITY
explicit __shared_weak_count(long __refs = 0) _NOEXCEPT
: __shared_count(__refs),
__shared_weak_owners_(__refs) {}
protected:
~__shared_weak_count() override;
public:
#if defined(_LIBCPP_SHARED_PTR_DEFINE_LEGACY_INLINE_FUNCTIONS)
void __add_shared() noexcept;
void __add_weak() noexcept;
void __release_shared() noexcept;
#else
_LIBCPP_INLINE_VISIBILITY
void __add_shared() _NOEXCEPT {
__shared_count::__add_shared();
}
_LIBCPP_INLINE_VISIBILITY
void __add_weak() _NOEXCEPT {
__libcpp_atomic_refcount_increment(__shared_weak_owners_);
}
_LIBCPP_INLINE_VISIBILITY
void __release_shared() _NOEXCEPT {
if (__shared_count::__release_shared())
__release_weak();
}
#endif
void __release_weak() _NOEXCEPT;
_LIBCPP_INLINE_VISIBILITY
long use_count() const _NOEXCEPT {return __shared_count::use_count();}
__shared_weak_count* lock() _NOEXCEPT;
virtual const void* __get_deleter(const type_info&) const _NOEXCEPT;
private:
virtual void __on_zero_shared_weak() _NOEXCEPT = 0;
};
template <class _Tp, class _Dp, class _Alloc>
class __shared_ptr_pointer
: public __shared_weak_count
{
__compressed_pair<__compressed_pair<_Tp, _Dp>, _Alloc> __data_;
public:
_LIBCPP_INLINE_VISIBILITY
__shared_ptr_pointer(_Tp __p, _Dp __d, _Alloc __a)
: __data_(__compressed_pair<_Tp, _Dp>(__p, _VSTD::move(__d)), _VSTD::move(__a)) {}
#ifndef _LIBCPP_NO_RTTI
const void* __get_deleter(const type_info&) const _NOEXCEPT override;
#endif
private:
void __on_zero_shared() _NOEXCEPT override;
void __on_zero_shared_weak() _NOEXCEPT override;
};
#ifndef _LIBCPP_NO_RTTI
template <class _Tp, class _Dp, class _Alloc>
const void*
__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__get_deleter(const type_info& __t) const _NOEXCEPT
{
return __t == typeid(_Dp) ? _VSTD::addressof(__data_.first().second()) : nullptr;
}
#endif // _LIBCPP_NO_RTTI
template <class _Tp, class _Dp, class _Alloc>
void
__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__on_zero_shared() _NOEXCEPT
{
__data_.first().second()(__data_.first().first());
__data_.first().second().~_Dp();
}
template <class _Tp, class _Dp, class _Alloc>
void
__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__on_zero_shared_weak() _NOEXCEPT
{
typedef typename __allocator_traits_rebind<_Alloc, __shared_ptr_pointer>::type _Al;
typedef allocator_traits<_Al> _ATraits;
typedef pointer_traits<typename _ATraits::pointer> _PTraits;
_Al __a(__data_.second());
__data_.second().~_Alloc();
__a.deallocate(_PTraits::pointer_to(*this), 1);
}
struct __default_initialize_tag {};
template <class _Tp, class _Alloc>
struct __shared_ptr_emplace
: __shared_weak_count
{
template<class ..._Args>
_LIBCPP_HIDE_FROM_ABI
explicit __shared_ptr_emplace(_Alloc __a, _Args&& ...__args)
: __storage_(_VSTD::move(__a))
{
#if _LIBCPP_STD_VER > 17
using _TpAlloc = typename __allocator_traits_rebind<_Alloc, _Tp>::type;
_TpAlloc __tmp(*__get_alloc());
allocator_traits<_TpAlloc>::construct(__tmp, __get_elem(), _VSTD::forward<_Args>(__args)...);
#else
::new ((void*)__get_elem()) _Tp(_VSTD::forward<_Args>(__args)...);
#endif
}
#if _LIBCPP_STD_VER >= 20
_LIBCPP_HIDE_FROM_ABI
explicit __shared_ptr_emplace(__default_initialize_tag, _Alloc __a)
: __storage_(std::move(__a))
{
::new ((void*)__get_elem()) _Tp;
}
#endif
_LIBCPP_HIDE_FROM_ABI
_Alloc* __get_alloc() _NOEXCEPT { return __storage_.__get_alloc(); }
_LIBCPP_HIDE_FROM_ABI
_Tp* __get_elem() _NOEXCEPT { return __storage_.__get_elem(); }
private:
void __on_zero_shared() _NOEXCEPT override {
#if _LIBCPP_STD_VER > 17
using _TpAlloc = typename __allocator_traits_rebind<_Alloc, _Tp>::type;
_TpAlloc __tmp(*__get_alloc());
allocator_traits<_TpAlloc>::destroy(__tmp, __get_elem());
#else
__get_elem()->~_Tp();
#endif
}
void __on_zero_shared_weak() _NOEXCEPT override {
using _ControlBlockAlloc = typename __allocator_traits_rebind<_Alloc, __shared_ptr_emplace>::type;
using _ControlBlockPointer = typename allocator_traits<_ControlBlockAlloc>::pointer;
_ControlBlockAlloc __tmp(*__get_alloc());
__storage_.~_Storage();
allocator_traits<_ControlBlockAlloc>::deallocate(__tmp,
pointer_traits<_ControlBlockPointer>::pointer_to(*this), 1);
}
// This class implements the control block for non-array shared pointers created
// through `std::allocate_shared` and `std::make_shared`.
//
// In previous versions of the library, we used a compressed pair to store
// both the _Alloc and the _Tp. This implies using EBO, which is incompatible
// with Allocator construction for _Tp. To allow implementing P0674 in C++20,
// we now use a properly aligned char buffer while making sure that we maintain
// the same layout that we had when we used a compressed pair.
using _CompressedPair = __compressed_pair<_Alloc, _Tp>;
struct _ALIGNAS_TYPE(_CompressedPair) _Storage {
char __blob_[sizeof(_CompressedPair)];
_LIBCPP_HIDE_FROM_ABI explicit _Storage(_Alloc&& __a) {
::new ((void*)__get_alloc()) _Alloc(_VSTD::move(__a));
}
_LIBCPP_HIDE_FROM_ABI ~_Storage() {
__get_alloc()->~_Alloc();
}
_Alloc* __get_alloc() _NOEXCEPT {
_CompressedPair *__as_pair = reinterpret_cast<_CompressedPair*>(__blob_);
typename _CompressedPair::_Base1* __first = _CompressedPair::__get_first_base(__as_pair);
_Alloc *__alloc = reinterpret_cast<_Alloc*>(__first);
return __alloc;
}
_LIBCPP_NO_CFI _Tp* __get_elem() _NOEXCEPT {
_CompressedPair *__as_pair = reinterpret_cast<_CompressedPair*>(__blob_);
typename _CompressedPair::_Base2* __second = _CompressedPair::__get_second_base(__as_pair);
_Tp *__elem = reinterpret_cast<_Tp*>(__second);
return __elem;
}
};
static_assert(_LIBCPP_ALIGNOF(_Storage) == _LIBCPP_ALIGNOF(_CompressedPair), "");
static_assert(sizeof(_Storage) == sizeof(_CompressedPair), "");
_Storage __storage_;
};
struct __shared_ptr_dummy_rebind_allocator_type;
template <>
class _LIBCPP_TEMPLATE_VIS allocator<__shared_ptr_dummy_rebind_allocator_type>
{
public:
template <class _Other>
struct rebind
{
typedef allocator<_Other> other;
};
};
template<class _Tp> class _LIBCPP_TEMPLATE_VIS enable_shared_from_this;
template<class _Tp, class _Up>
struct __compatible_with
#if _LIBCPP_STD_VER > 14
: is_convertible<remove_extent_t<_Tp>*, remove_extent_t<_Up>*> {};
#else
: is_convertible<_Tp*, _Up*> {};
#endif // _LIBCPP_STD_VER > 14
template <class _Ptr, class = void>
struct __is_deletable : false_type { };
template <class _Ptr>
struct __is_deletable<_Ptr, decltype(delete std::declval<_Ptr>())> : true_type { };
template <class _Ptr, class = void>
struct __is_array_deletable : false_type { };
template <class _Ptr>
struct __is_array_deletable<_Ptr, decltype(delete[] std::declval<_Ptr>())> : true_type { };
template <class _Dp, class _Pt,
class = decltype(std::declval<_Dp>()(std::declval<_Pt>()))>
static true_type __well_formed_deleter_test(int);
template <class, class>
static false_type __well_formed_deleter_test(...);
template <class _Dp, class _Pt>
struct __well_formed_deleter : decltype(std::__well_formed_deleter_test<_Dp, _Pt>(0)) {};
template<class _Dp, class _Tp, class _Yp>
struct __shared_ptr_deleter_ctor_reqs
{
static const bool value = __compatible_with<_Tp, _Yp>::value &&
is_move_constructible<_Dp>::value &&
__well_formed_deleter<_Dp, _Tp*>::value;
};
#if defined(_LIBCPP_ABI_ENABLE_SHARED_PTR_TRIVIAL_ABI)
# define _LIBCPP_SHARED_PTR_TRIVIAL_ABI __attribute__((trivial_abi))
#else
# define _LIBCPP_SHARED_PTR_TRIVIAL_ABI
#endif
template<class _Tp>
class _LIBCPP_SHARED_PTR_TRIVIAL_ABI _LIBCPP_TEMPLATE_VIS shared_ptr
{
public:
#if _LIBCPP_STD_VER > 14
typedef weak_ptr<_Tp> weak_type;
typedef remove_extent_t<_Tp> element_type;
#else
typedef _Tp element_type;
#endif
private:
element_type* __ptr_;
__shared_weak_count* __cntrl_;
public:
_LIBCPP_HIDE_FROM_ABI
_LIBCPP_CONSTEXPR shared_ptr() _NOEXCEPT
: __ptr_(nullptr),
__cntrl_(nullptr)
{ }
_LIBCPP_HIDE_FROM_ABI
_LIBCPP_CONSTEXPR shared_ptr(nullptr_t) _NOEXCEPT
: __ptr_(nullptr),
__cntrl_(nullptr)
{ }
template<class _Yp, class = __enable_if_t<
_And<
__compatible_with<_Yp, _Tp>
// In C++03 we get errors when trying to do SFINAE with the
// delete operator, so we always pretend that it's deletable.
// The same happens on GCC.
#if !defined(_LIBCPP_CXX03_LANG) && !defined(_LIBCPP_COMPILER_GCC)
, _If<is_array<_Tp>::value, __is_array_deletable<_Yp*>, __is_deletable<_Yp*> >
#endif
>::value
> >
explicit shared_ptr(_Yp* __p) : __ptr_(__p) {
unique_ptr<_Yp> __hold(__p);
typedef typename __shared_ptr_default_allocator<_Yp>::type _AllocT;
typedef __shared_ptr_pointer<_Yp*, __shared_ptr_default_delete<_Tp, _Yp>, _AllocT> _CntrlBlk;
__cntrl_ = new _CntrlBlk(__p, __shared_ptr_default_delete<_Tp, _Yp>(), _AllocT());
__hold.release();
__enable_weak_this(__p, __p);
}
template<class _Yp, class _Dp, class = __enable_if_t<__shared_ptr_deleter_ctor_reqs<_Dp, _Yp, element_type>::value> >
_LIBCPP_HIDE_FROM_ABI
shared_ptr(_Yp* __p, _Dp __d)
: __ptr_(__p)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
try
{
#endif // _LIBCPP_NO_EXCEPTIONS
typedef typename __shared_ptr_default_allocator<_Yp>::type _AllocT;
typedef __shared_ptr_pointer<_Yp*, _Dp, _AllocT> _CntrlBlk;
#ifndef _LIBCPP_CXX03_LANG
__cntrl_ = new _CntrlBlk(__p, _VSTD::move(__d), _AllocT());
#else
__cntrl_ = new _CntrlBlk(__p, __d, _AllocT());
#endif // not _LIBCPP_CXX03_LANG
__enable_weak_this(__p, __p);
#ifndef _LIBCPP_NO_EXCEPTIONS
}
catch (...)
{
__d(__p);
throw;
}
#endif // _LIBCPP_NO_EXCEPTIONS
}
template<class _Yp, class _Dp, class _Alloc, class = __enable_if_t<__shared_ptr_deleter_ctor_reqs<_Dp, _Yp, element_type>::value> >
_LIBCPP_HIDE_FROM_ABI
shared_ptr(_Yp* __p, _Dp __d, _Alloc __a)
: __ptr_(__p)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
try
{
#endif // _LIBCPP_NO_EXCEPTIONS
typedef __shared_ptr_pointer<_Yp*, _Dp, _Alloc> _CntrlBlk;
typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
typedef __allocator_destructor<_A2> _D2;
_A2 __a2(__a);
unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
::new ((void*)_VSTD::addressof(*__hold2.get()))
#ifndef _LIBCPP_CXX03_LANG
_CntrlBlk(__p, _VSTD::move(__d), __a);
#else
_CntrlBlk(__p, __d, __a);
#endif // not _LIBCPP_CXX03_LANG
__cntrl_ = _VSTD::addressof(*__hold2.release());
__enable_weak_this(__p, __p);
#ifndef _LIBCPP_NO_EXCEPTIONS
}
catch (...)
{
__d(__p);
throw;
}
#endif // _LIBCPP_NO_EXCEPTIONS
}
template<class _Dp>
_LIBCPP_HIDE_FROM_ABI
shared_ptr(nullptr_t __p, _Dp __d)
: __ptr_(nullptr)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
try
{
#endif // _LIBCPP_NO_EXCEPTIONS
typedef typename __shared_ptr_default_allocator<_Tp>::type _AllocT;
typedef __shared_ptr_pointer<nullptr_t, _Dp, _AllocT> _CntrlBlk;
#ifndef _LIBCPP_CXX03_LANG
__cntrl_ = new _CntrlBlk(__p, _VSTD::move(__d), _AllocT());
#else
__cntrl_ = new _CntrlBlk(__p, __d, _AllocT());
#endif // not _LIBCPP_CXX03_LANG
#ifndef _LIBCPP_NO_EXCEPTIONS
}
catch (...)
{
__d(__p);
throw;
}
#endif // _LIBCPP_NO_EXCEPTIONS
}
template<class _Dp, class _Alloc>
_LIBCPP_HIDE_FROM_ABI
shared_ptr(nullptr_t __p, _Dp __d, _Alloc __a)
: __ptr_(nullptr)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
try
{
#endif // _LIBCPP_NO_EXCEPTIONS
typedef __shared_ptr_pointer<nullptr_t, _Dp, _Alloc> _CntrlBlk;
typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
typedef __allocator_destructor<_A2> _D2;
_A2 __a2(__a);
unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
::new ((void*)_VSTD::addressof(*__hold2.get()))
#ifndef _LIBCPP_CXX03_LANG
_CntrlBlk(__p, _VSTD::move(__d), __a);
#else
_CntrlBlk(__p, __d, __a);
#endif // not _LIBCPP_CXX03_LANG
__cntrl_ = _VSTD::addressof(*__hold2.release());
#ifndef _LIBCPP_NO_EXCEPTIONS
}
catch (...)
{
__d(__p);
throw;
}
#endif // _LIBCPP_NO_EXCEPTIONS
}
template<class _Yp>
_LIBCPP_HIDE_FROM_ABI
shared_ptr(const shared_ptr<_Yp>& __r, element_type *__p) _NOEXCEPT
: __ptr_(__p),
__cntrl_(__r.__cntrl_)
{
if (__cntrl_)
__cntrl_->__add_shared();
}
_LIBCPP_HIDE_FROM_ABI
shared_ptr(const shared_ptr& __r) _NOEXCEPT
: __ptr_(__r.__ptr_),
__cntrl_(__r.__cntrl_)
{
if (__cntrl_)
__cntrl_->__add_shared();
}
template<class _Yp, class = __enable_if_t<__compatible_with<_Yp, _Tp>::value> >
_LIBCPP_HIDE_FROM_ABI
shared_ptr(const shared_ptr<_Yp>& __r) _NOEXCEPT
: __ptr_(__r.__ptr_),
__cntrl_(__r.__cntrl_)
{
if (__cntrl_)
__cntrl_->__add_shared();
}
_LIBCPP_HIDE_FROM_ABI
shared_ptr(shared_ptr&& __r) _NOEXCEPT
: __ptr_(__r.__ptr_),
__cntrl_(__r.__cntrl_)
{
__r.__ptr_ = nullptr;
__r.__cntrl_ = nullptr;
}
template<class _Yp, class = __enable_if_t<__compatible_with<_Yp, _Tp>::value> >
_LIBCPP_HIDE_FROM_ABI
shared_ptr(shared_ptr<_Yp>&& __r) _NOEXCEPT
: __ptr_(__r.__ptr_),
__cntrl_(__r.__cntrl_)
{
__r.__ptr_ = nullptr;
__r.__cntrl_ = nullptr;
}
template<class _Yp, class = __enable_if_t<__compatible_with<_Yp, _Tp>::value> >
_LIBCPP_HIDE_FROM_ABI
explicit shared_ptr(const weak_ptr<_Yp>& __r)
: __ptr_(__r.__ptr_),
__cntrl_(__r.__cntrl_ ? __r.__cntrl_->lock() : __r.__cntrl_)
{
if (__cntrl_ == nullptr)
__throw_bad_weak_ptr();
}
#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
template<class _Yp, class = __enable_if_t<is_convertible<_Yp*, element_type*>::value> >
_LIBCPP_HIDE_FROM_ABI
shared_ptr(auto_ptr<_Yp>&& __r)
: __ptr_(__r.get())
{
typedef __shared_ptr_pointer<_Yp*, default_delete<_Yp>, allocator<_Yp> > _CntrlBlk;
__cntrl_ = new _CntrlBlk(__r.get(), default_delete<_Yp>(), allocator<_Yp>());
__enable_weak_this(__r.get(), __r.get());
__r.release();
}
#endif
template <class _Yp, class _Dp, class = __enable_if_t<
!is_lvalue_reference<_Dp>::value &&
is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value
> >
_LIBCPP_HIDE_FROM_ABI
shared_ptr(unique_ptr<_Yp, _Dp>&& __r)
: __ptr_(__r.get())
{
#if _LIBCPP_STD_VER > 11
if (__ptr_ == nullptr)
__cntrl_ = nullptr;
else
#endif
{
typedef typename __shared_ptr_default_allocator<_Yp>::type _AllocT;
typedef __shared_ptr_pointer<typename unique_ptr<_Yp, _Dp>::pointer, _Dp, _AllocT> _CntrlBlk;
__cntrl_ = new _CntrlBlk(__r.get(), std::move(__r.get_deleter()), _AllocT());
__enable_weak_this(__r.get(), __r.get());
}
__r.release();
}
template <class _Yp, class _Dp, class = void, class = __enable_if_t<
is_lvalue_reference<_Dp>::value &&
is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value
> >
_LIBCPP_HIDE_FROM_ABI
shared_ptr(unique_ptr<_Yp, _Dp>&& __r)
: __ptr_(__r.get())
{
#if _LIBCPP_STD_VER > 11
if (__ptr_ == nullptr)
__cntrl_ = nullptr;
else
#endif
{
typedef typename __shared_ptr_default_allocator<_Yp>::type _AllocT;
typedef __shared_ptr_pointer<typename unique_ptr<_Yp, _Dp>::pointer,
reference_wrapper<__libcpp_remove_reference_t<_Dp> >,
_AllocT> _CntrlBlk;
__cntrl_ = new _CntrlBlk(__r.get(), _VSTD::ref(__r.get_deleter()), _AllocT());
__enable_weak_this(__r.get(), __r.get());
}
__r.release();
}
_LIBCPP_HIDE_FROM_ABI
~shared_ptr()
{
if (__cntrl_)
__cntrl_->__release_shared();
}
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp>& operator=(const shared_ptr& __r) _NOEXCEPT
{
shared_ptr(__r).swap(*this);
return *this;
}
template<class _Yp, class = __enable_if_t<__compatible_with<_Yp, _Tp>::value> >
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp>& operator=(const shared_ptr<_Yp>& __r) _NOEXCEPT
{
shared_ptr(__r).swap(*this);
return *this;
}
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp>& operator=(shared_ptr&& __r) _NOEXCEPT
{
shared_ptr(_VSTD::move(__r)).swap(*this);
return *this;
}
template<class _Yp, class = __enable_if_t<__compatible_with<_Yp, _Tp>::value> >
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp>& operator=(shared_ptr<_Yp>&& __r)
{
shared_ptr(_VSTD::move(__r)).swap(*this);
return *this;
}
#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
template<class _Yp, class = __enable_if_t<
!is_array<_Yp>::value &&
is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value
> >
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp>& operator=(auto_ptr<_Yp>&& __r)
{
shared_ptr(_VSTD::move(__r)).swap(*this);
return *this;
}
#endif
template <class _Yp, class _Dp, class = __enable_if_t<
is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value
> >
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp>& operator=(unique_ptr<_Yp, _Dp>&& __r)
{
shared_ptr(_VSTD::move(__r)).swap(*this);
return *this;
}
_LIBCPP_HIDE_FROM_ABI
void swap(shared_ptr& __r) _NOEXCEPT
{
_VSTD::swap(__ptr_, __r.__ptr_);
_VSTD::swap(__cntrl_, __r.__cntrl_);
}
_LIBCPP_HIDE_FROM_ABI
void reset() _NOEXCEPT
{
shared_ptr().swap(*this);
}
template<class _Yp, class = __enable_if_t<
__compatible_with<_Yp, _Tp>::value
> >
_LIBCPP_HIDE_FROM_ABI
void reset(_Yp* __p)
{
shared_ptr(__p).swap(*this);
}
template<class _Yp, class _Dp, class = __enable_if_t<
__compatible_with<_Yp, _Tp>::value
> >
_LIBCPP_HIDE_FROM_ABI
void reset(_Yp* __p, _Dp __d)
{
shared_ptr(__p, __d).swap(*this);
}
template<class _Yp, class _Dp, class _Alloc, class = __enable_if_t<
__compatible_with<_Yp, _Tp>::value
> >
_LIBCPP_HIDE_FROM_ABI
void reset(_Yp* __p, _Dp __d, _Alloc __a)
{
shared_ptr(__p, __d, __a).swap(*this);
}
_LIBCPP_HIDE_FROM_ABI
element_type* get() const _NOEXCEPT
{
return __ptr_;
}
_LIBCPP_HIDE_FROM_ABI
__add_lvalue_reference_t<element_type> operator*() const _NOEXCEPT
{
return *__ptr_;
}
_LIBCPP_HIDE_FROM_ABI
element_type* operator->() const _NOEXCEPT
{
static_assert(!is_array<_Tp>::value,
"std::shared_ptr<T>::operator-> is only valid when T is not an array type.");
return __ptr_;
}
_LIBCPP_HIDE_FROM_ABI
long use_count() const _NOEXCEPT
{
return __cntrl_ ? __cntrl_->use_count() : 0;
}
_LIBCPP_HIDE_FROM_ABI
bool unique() const _NOEXCEPT
{
return use_count() == 1;
}
_LIBCPP_HIDE_FROM_ABI
explicit operator bool() const _NOEXCEPT
{
return get() != nullptr;
}
template <class _Up>
_LIBCPP_HIDE_FROM_ABI
bool owner_before(shared_ptr<_Up> const& __p) const _NOEXCEPT
{
return __cntrl_ < __p.__cntrl_;
}
template <class _Up>
_LIBCPP_HIDE_FROM_ABI
bool owner_before(weak_ptr<_Up> const& __p) const _NOEXCEPT
{
return __cntrl_ < __p.__cntrl_;
}
_LIBCPP_HIDE_FROM_ABI
bool __owner_equivalent(const shared_ptr& __p) const
{
return __cntrl_ == __p.__cntrl_;
}
#if _LIBCPP_STD_VER > 14
_LIBCPP_HIDE_FROM_ABI
__add_lvalue_reference_t<element_type> operator[](ptrdiff_t __i) const
{
static_assert(is_array<_Tp>::value,
"std::shared_ptr<T>::operator[] is only valid when T is an array type.");
return __ptr_[__i];
}
#endif
#ifndef _LIBCPP_NO_RTTI
template <class _Dp>
_LIBCPP_HIDE_FROM_ABI
_Dp* __get_deleter() const _NOEXCEPT
{
return static_cast<_Dp*>(__cntrl_
? const_cast<void *>(__cntrl_->__get_deleter(typeid(_Dp)))
: nullptr);
}
#endif // _LIBCPP_NO_RTTI
template<class _Yp, class _CntrlBlk>
_LIBCPP_HIDE_FROM_ABI
static shared_ptr<_Tp> __create_with_control_block(_Yp* __p, _CntrlBlk* __cntrl) _NOEXCEPT
{
shared_ptr<_Tp> __r;
__r.__ptr_ = __p;
__r.__cntrl_ = __cntrl;
__r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
return __r;
}
private:
template <class _Yp, bool = is_function<_Yp>::value>
struct __shared_ptr_default_allocator
{
typedef allocator<_Yp> type;
};
template <class _Yp>
struct __shared_ptr_default_allocator<_Yp, true>
{
typedef allocator<__shared_ptr_dummy_rebind_allocator_type> type;
};
template <class _Yp, class _OrigPtr, class = __enable_if_t<
is_convertible<_OrigPtr*, const enable_shared_from_this<_Yp>*>::value
> >
_LIBCPP_HIDE_FROM_ABI
void __enable_weak_this(const enable_shared_from_this<_Yp>* __e, _OrigPtr* __ptr) _NOEXCEPT
{
typedef __remove_cv_t<_Yp> _RawYp;
if (__e && __e->__weak_this_.expired())
{
__e->__weak_this_ = shared_ptr<_RawYp>(*this,
const_cast<_RawYp*>(static_cast<const _Yp*>(__ptr)));
}
}
_LIBCPP_HIDE_FROM_ABI void __enable_weak_this(...) _NOEXCEPT { }
template <class, class _Yp>
struct __shared_ptr_default_delete
: default_delete<_Yp>
{ };
template <class _Yp, class _Un, size_t _Sz>
struct __shared_ptr_default_delete<_Yp[_Sz], _Un>
: default_delete<_Yp[]>
{ };
template <class _Yp, class _Un>
struct __shared_ptr_default_delete<_Yp[], _Un>
: default_delete<_Yp[]>
{ };
template <class _Up> friend class _LIBCPP_TEMPLATE_VIS shared_ptr;
template <class _Up> friend class _LIBCPP_TEMPLATE_VIS weak_ptr;
};
#if _LIBCPP_STD_VER > 14
template<class _Tp>
shared_ptr(weak_ptr<_Tp>) -> shared_ptr<_Tp>;
template<class _Tp, class _Dp>
shared_ptr(unique_ptr<_Tp, _Dp>) -> shared_ptr<_Tp>;
#endif
//
// std::allocate_shared and std::make_shared
//
template<class _Tp, class _Alloc, class ..._Args, class = __enable_if_t<!is_array<_Tp>::value> >
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp> allocate_shared(const _Alloc& __a, _Args&& ...__args)
{
using _ControlBlock = __shared_ptr_emplace<_Tp, _Alloc>;
using _ControlBlockAllocator = typename __allocator_traits_rebind<_Alloc, _ControlBlock>::type;
__allocation_guard<_ControlBlockAllocator> __guard(__a, 1);
::new ((void*)_VSTD::addressof(*__guard.__get())) _ControlBlock(__a, _VSTD::forward<_Args>(__args)...);
auto __control_block = __guard.__release_ptr();
return shared_ptr<_Tp>::__create_with_control_block((*__control_block).__get_elem(), _VSTD::addressof(*__control_block));
}
template<class _Tp, class ..._Args, class = __enable_if_t<!is_array<_Tp>::value> >
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp> make_shared(_Args&& ...__args)
{
return _VSTD::allocate_shared<_Tp>(allocator<_Tp>(), _VSTD::forward<_Args>(__args)...);
}
#if _LIBCPP_STD_VER >= 20
template<class _Tp, class _Alloc, __enable_if_t<!is_array<_Tp>::value, int> = 0>
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp> allocate_shared_for_overwrite(const _Alloc& __a)
{
using _ControlBlock = __shared_ptr_emplace<_Tp, _Alloc>;
using _ControlBlockAllocator = typename __allocator_traits_rebind<_Alloc, _ControlBlock>::type;
__allocation_guard<_ControlBlockAllocator> __guard(__a, 1);
::new ((void*)_VSTD::addressof(*__guard.__get())) _ControlBlock(__default_initialize_tag{}, __a);
auto __control_block = __guard.__release_ptr();
return shared_ptr<_Tp>::__create_with_control_block((*__control_block).__get_elem(), _VSTD::addressof(*__control_block));
}
template<class _Tp, __enable_if_t<!is_array<_Tp>::value, int> = 0>
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp> make_shared_for_overwrite()
{
return std::allocate_shared_for_overwrite<_Tp>(allocator<_Tp>());
}
#endif // _LIBCPP_STD_VER >= 20
#if _LIBCPP_STD_VER > 14
template <size_t _Alignment>
struct __sp_aligned_storage {
alignas(_Alignment) char __storage[_Alignment];
};
template <class _Tp, class _Alloc>
struct __unbounded_array_control_block;
template <class _Tp, class _Alloc>
struct __unbounded_array_control_block<_Tp[], _Alloc> : __shared_weak_count
{
_LIBCPP_HIDE_FROM_ABI constexpr
_Tp* __get_data() noexcept { return __data_; }
_LIBCPP_HIDE_FROM_ABI
explicit __unbounded_array_control_block(_Alloc const& __alloc, size_t __count, _Tp const& __arg)
: __alloc_(__alloc), __count_(__count)
{
std::__uninitialized_allocator_fill_n(__alloc_, std::begin(__data_), __count_, __arg);
}
_LIBCPP_HIDE_FROM_ABI
explicit __unbounded_array_control_block(_Alloc const& __alloc, size_t __count)
: __alloc_(__alloc), __count_(__count)
{
std::__uninitialized_allocator_value_construct_n(__alloc_, std::begin(__data_), __count_);
}
#if _LIBCPP_STD_VER >= 20
_LIBCPP_HIDE_FROM_ABI
explicit __unbounded_array_control_block(_Alloc const& __alloc, size_t __count, __default_initialize_tag)
: __alloc_(__alloc), __count_(__count)
{
// We are purposefully not using an allocator-aware default construction because the spec says so.
// There's currently no way of expressing default initialization in an allocator-aware manner anyway.
std::uninitialized_default_construct_n(std::begin(__data_), __count_);
}
#endif
// Returns the number of bytes required to store a control block followed by the given number
// of elements of _Tp, with the whole storage being aligned to a multiple of _Tp's alignment.
_LIBCPP_HIDE_FROM_ABI
static constexpr size_t __bytes_for(size_t __elements) {
// When there's 0 elements, the control block alone is enough since it holds one element.
// Otherwise, we allocate one fewer element than requested because the control block already
// holds one. Also, we use the bitwise formula below to ensure that we allocate enough bytes
// for the whole allocation to be a multiple of _Tp's alignment. That formula is taken from [1].
//
// [1]: https://en.wikipedia.org/wiki/Data_structure_alignment#Computing_padding
size_t __bytes = __elements == 0 ? sizeof(__unbounded_array_control_block)
: (__elements - 1) * sizeof(_Tp) + sizeof(__unbounded_array_control_block);
constexpr size_t __align = alignof(_Tp);
return (__bytes + __align - 1) & ~(__align - 1);
}
_LIBCPP_HIDE_FROM_ABI_VIRTUAL
~__unbounded_array_control_block() override { } // can't be `= default` because of the sometimes-non-trivial union member __data_
private:
void __on_zero_shared() _NOEXCEPT override {
__allocator_traits_rebind_t<_Alloc, _Tp> __value_alloc(__alloc_);
std::__allocator_destroy_multidimensional(__value_alloc, __data_, __data_ + __count_);
}
void __on_zero_shared_weak() _NOEXCEPT override {
using _AlignedStorage = __sp_aligned_storage<alignof(__unbounded_array_control_block)>;
using _StorageAlloc = __allocator_traits_rebind_t<_Alloc, _AlignedStorage>;
using _PointerTraits = pointer_traits<typename allocator_traits<_StorageAlloc>::pointer>;
_StorageAlloc __tmp(__alloc_);
__alloc_.~_Alloc();
size_t __size = __unbounded_array_control_block::__bytes_for(__count_);
_AlignedStorage* __storage = reinterpret_cast<_AlignedStorage*>(this);
allocator_traits<_StorageAlloc>::deallocate(__tmp, _PointerTraits::pointer_to(*__storage), __size);
}
_LIBCPP_NO_UNIQUE_ADDRESS _Alloc __alloc_;
size_t __count_;
union {
_Tp __data_[1];
};
};
template<class _Array, class _Alloc, class... _Arg>
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Array> __allocate_shared_unbounded_array(const _Alloc& __a, size_t __n, _Arg&& ...__arg)
{
static_assert(__libcpp_is_unbounded_array<_Array>::value);
// We compute the number of bytes necessary to hold the control block and the
// array elements. Then, we allocate an array of properly-aligned dummy structs
// large enough to hold the control block and array. This allows shifting the
// burden of aligning memory properly from us to the allocator.
using _ControlBlock = __unbounded_array_control_block<_Array, _Alloc>;
using _AlignedStorage = __sp_aligned_storage<alignof(_ControlBlock)>;
using _StorageAlloc = __allocator_traits_rebind_t<_Alloc, _AlignedStorage>;
__allocation_guard<_StorageAlloc> __guard(__a, _ControlBlock::__bytes_for(__n) / sizeof(_AlignedStorage));
_ControlBlock* __control_block = reinterpret_cast<_ControlBlock*>(std::addressof(*__guard.__get()));
std::__construct_at(__control_block, __a, __n, std::forward<_Arg>(__arg)...);
__guard.__release_ptr();
return shared_ptr<_Array>::__create_with_control_block(__control_block->__get_data(), __control_block);
}
template <class _Tp, class _Alloc>
struct __bounded_array_control_block;
template <class _Tp, size_t _Count, class _Alloc>
struct __bounded_array_control_block<_Tp[_Count], _Alloc>
: __shared_weak_count
{
_LIBCPP_HIDE_FROM_ABI constexpr
_Tp* __get_data() noexcept { return __data_; }
_LIBCPP_HIDE_FROM_ABI
explicit __bounded_array_control_block(_Alloc const& __alloc, _Tp const& __arg) : __alloc_(__alloc) {
std::__uninitialized_allocator_fill_n(__alloc_, std::addressof(__data_[0]), _Count, __arg);
}
_LIBCPP_HIDE_FROM_ABI
explicit __bounded_array_control_block(_Alloc const& __alloc) : __alloc_(__alloc) {
std::__uninitialized_allocator_value_construct_n(__alloc_, std::addressof(__data_[0]), _Count);
}
#if _LIBCPP_STD_VER >= 20
_LIBCPP_HIDE_FROM_ABI
explicit __bounded_array_control_block(_Alloc const& __alloc, __default_initialize_tag) : __alloc_(__alloc) {
// We are purposefully not using an allocator-aware default construction because the spec says so.
// There's currently no way of expressing default initialization in an allocator-aware manner anyway.
std::uninitialized_default_construct_n(std::addressof(__data_[0]), _Count);
}
#endif
_LIBCPP_HIDE_FROM_ABI_VIRTUAL
~__bounded_array_control_block() override { } // can't be `= default` because of the sometimes-non-trivial union member __data_
private:
void __on_zero_shared() _NOEXCEPT override {
__allocator_traits_rebind_t<_Alloc, _Tp> __value_alloc(__alloc_);
std::__allocator_destroy_multidimensional(__value_alloc, __data_, __data_ + _Count);
}
void __on_zero_shared_weak() _NOEXCEPT override {
using _ControlBlockAlloc = __allocator_traits_rebind_t<_Alloc, __bounded_array_control_block>;
using _PointerTraits = pointer_traits<typename allocator_traits<_ControlBlockAlloc>::pointer>;
_ControlBlockAlloc __tmp(__alloc_);
__alloc_.~_Alloc();
allocator_traits<_ControlBlockAlloc>::deallocate(__tmp, _PointerTraits::pointer_to(*this), sizeof(*this));
}
_LIBCPP_NO_UNIQUE_ADDRESS _Alloc __alloc_;
union {
_Tp __data_[_Count];
};
};
template<class _Array, class _Alloc, class... _Arg>
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Array> __allocate_shared_bounded_array(const _Alloc& __a, _Arg&& ...__arg)
{
static_assert(__libcpp_is_bounded_array<_Array>::value);
using _ControlBlock = __bounded_array_control_block<_Array, _Alloc>;
using _ControlBlockAlloc = __allocator_traits_rebind_t<_Alloc, _ControlBlock>;
__allocation_guard<_ControlBlockAlloc> __guard(__a, 1);
_ControlBlock* __control_block = reinterpret_cast<_ControlBlock*>(std::addressof(*__guard.__get()));
std::__construct_at(__control_block, __a, std::forward<_Arg>(__arg)...);
__guard.__release_ptr();
return shared_ptr<_Array>::__create_with_control_block(__control_block->__get_data(), __control_block);
}
#endif // _LIBCPP_STD_VER > 14
#if _LIBCPP_STD_VER > 17
// bounded array variants
template<class _Tp, class _Alloc, class = __enable_if_t<is_bounded_array<_Tp>::value>>
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp> allocate_shared(const _Alloc& __a)
{
return std::__allocate_shared_bounded_array<_Tp>(__a);
}
template<class _Tp, class _Alloc, class = __enable_if_t<is_bounded_array<_Tp>::value>>
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp> allocate_shared(const _Alloc& __a, const remove_extent_t<_Tp>& __u)
{
return std::__allocate_shared_bounded_array<_Tp>(__a, __u);
}
template<class _Tp, class _Alloc, __enable_if_t<is_bounded_array<_Tp>::value, int> = 0>
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp> allocate_shared_for_overwrite(const _Alloc& __a)
{
return std::__allocate_shared_bounded_array<_Tp>(__a, __default_initialize_tag{});
}
template<class _Tp, class = __enable_if_t<is_bounded_array<_Tp>::value>>
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp> make_shared()
{
return std::__allocate_shared_bounded_array<_Tp>(allocator<_Tp>());
}
template<class _Tp, class = __enable_if_t<is_bounded_array<_Tp>::value>>
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp> make_shared(const remove_extent_t<_Tp>& __u)
{
return std::__allocate_shared_bounded_array<_Tp>(allocator<_Tp>(), __u);
}
template<class _Tp, __enable_if_t<is_bounded_array<_Tp>::value, int> = 0>
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp> make_shared_for_overwrite()
{
return std::__allocate_shared_bounded_array<_Tp>(allocator<_Tp>(), __default_initialize_tag{});
}
// unbounded array variants
template<class _Tp, class _Alloc, class = __enable_if_t<is_unbounded_array<_Tp>::value>>
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp> allocate_shared(const _Alloc& __a, size_t __n)
{
return std::__allocate_shared_unbounded_array<_Tp>(__a, __n);
}
template<class _Tp, class _Alloc, class = __enable_if_t<is_unbounded_array<_Tp>::value>>
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp> allocate_shared(const _Alloc& __a, size_t __n, const remove_extent_t<_Tp>& __u)
{
return std::__allocate_shared_unbounded_array<_Tp>(__a, __n, __u);
}
template<class _Tp, class _Alloc, __enable_if_t<is_unbounded_array<_Tp>::value, int> = 0>
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp> allocate_shared_for_overwrite(const _Alloc& __a, size_t __n)
{
return std::__allocate_shared_unbounded_array<_Tp>(__a, __n, __default_initialize_tag{});
}
template<class _Tp, class = __enable_if_t<is_unbounded_array<_Tp>::value>>
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp> make_shared(size_t __n)
{
return std::__allocate_shared_unbounded_array<_Tp>(allocator<_Tp>(), __n);
}
template<class _Tp, class = __enable_if_t<is_unbounded_array<_Tp>::value>>
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp> make_shared(size_t __n, const remove_extent_t<_Tp>& __u)
{
return std::__allocate_shared_unbounded_array<_Tp>(allocator<_Tp>(), __n, __u);
}
template<class _Tp, __enable_if_t<is_unbounded_array<_Tp>::value, int> = 0>
_LIBCPP_HIDE_FROM_ABI
shared_ptr<_Tp> make_shared_for_overwrite(size_t __n)
{
return std::__allocate_shared_unbounded_array<_Tp>(allocator<_Tp>(), __n, __default_initialize_tag{});
}
#endif // _LIBCPP_STD_VER > 17
template<class _Tp, class _Up>
inline _LIBCPP_INLINE_VISIBILITY
bool
operator==(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
{
return __x.get() == __y.get();
}
#if _LIBCPP_STD_VER <= 17
template<class _Tp, class _Up>
inline _LIBCPP_INLINE_VISIBILITY
bool
operator!=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
{
return !(__x == __y);
}
template<class _Tp, class _Up>
inline _LIBCPP_INLINE_VISIBILITY
bool
operator<(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
{
#if _LIBCPP_STD_VER <= 11
typedef typename common_type<_Tp*, _Up*>::type _Vp;
return less<_Vp>()(__x.get(), __y.get());
#else
return less<>()(__x.get(), __y.get());
#endif
}
template<class _Tp, class _Up>
inline _LIBCPP_INLINE_VISIBILITY
bool
operator>(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
{
return __y < __x;
}
template<class _Tp, class _Up>
inline _LIBCPP_INLINE_VISIBILITY
bool
operator<=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
{
return !(__y < __x);
}
template<class _Tp, class _Up>
inline _LIBCPP_INLINE_VISIBILITY
bool
operator>=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
{
return !(__x < __y);
}
#endif // _LIBCPP_STD_VER <= 17
#if _LIBCPP_STD_VER > 17
template<class _Tp, class _Up>
_LIBCPP_HIDE_FROM_ABI strong_ordering
operator<=>(shared_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) noexcept
{
return compare_three_way()(__x.get(), __y.get());
}
#endif
template<class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
bool
operator==(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
{
return !__x;
}
#if _LIBCPP_STD_VER <= 17
template<class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
bool
operator==(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
{
return !__x;
}
template<class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
bool
operator!=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
{
return static_cast<bool>(__x);
}
template<class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
bool
operator!=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
{
return static_cast<bool>(__x);
}
template<class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
bool
operator<(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
{
return less<_Tp*>()(__x.get(), nullptr);
}
template<class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
bool
operator<(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
{
return less<_Tp*>()(nullptr, __x.get());
}
template<class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
bool
operator>(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
{
return nullptr < __x;
}
template<class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
bool
operator>(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
{
return __x < nullptr;
}
template<class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
bool
operator<=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
{
return !(nullptr < __x);
}
template<class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
bool
operator<=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
{
return !(__x < nullptr);
}
template<class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
bool
operator>=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
{
return !(__x < nullptr);
}
template<class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
bool
operator>=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
{
return !(nullptr < __x);
}
#endif // _LIBCPP_STD_VER <= 17
#if _LIBCPP_STD_VER > 17
template<class _Tp>
_LIBCPP_HIDE_FROM_ABI strong_ordering
operator<=>(shared_ptr<_Tp> const& __x, nullptr_t) noexcept
{
return compare_three_way()(__x.get(), static_cast<typename shared_ptr<_Tp>::element_type*>(nullptr));
}
#endif
template<class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
void
swap(shared_ptr<_Tp>& __x, shared_ptr<_Tp>& __y) _NOEXCEPT
{
__x.swap(__y);
}
template<class _Tp, class _Up>
inline _LIBCPP_INLINE_VISIBILITY
shared_ptr<_Tp>
static_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
{
return shared_ptr<_Tp>(__r,
static_cast<
typename shared_ptr<_Tp>::element_type*>(__r.get()));
}
template<class _Tp, class _Up>
inline _LIBCPP_INLINE_VISIBILITY
shared_ptr<_Tp>
dynamic_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
{
typedef typename shared_ptr<_Tp>::element_type _ET;
_ET* __p = dynamic_cast<_ET*>(__r.get());
return __p ? shared_ptr<_Tp>(__r, __p) : shared_ptr<_Tp>();
}
template<class _Tp, class _Up>
_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp>
const_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
{
typedef typename shared_ptr<_Tp>::element_type _RTp;
return shared_ptr<_Tp>(__r, const_cast<_RTp*>(__r.get()));
}
template<class _Tp, class _Up>
_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp>
reinterpret_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
{
return shared_ptr<_Tp>(__r,
reinterpret_cast<
typename shared_ptr<_Tp>::element_type*>(__r.get()));
}
#ifndef _LIBCPP_NO_RTTI
template<class _Dp, class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
_Dp*
get_deleter(const shared_ptr<_Tp>& __p) _NOEXCEPT
{
return __p.template __get_deleter<_Dp>();
}
#endif // _LIBCPP_NO_RTTI
template<class _Tp>
class _LIBCPP_SHARED_PTR_TRIVIAL_ABI _LIBCPP_TEMPLATE_VIS weak_ptr
{
public:
#if _LIBCPP_STD_VER > 14
typedef remove_extent_t<_Tp> element_type;
#else
typedef _Tp element_type;
#endif
private:
element_type* __ptr_;
__shared_weak_count* __cntrl_;
public:
_LIBCPP_INLINE_VISIBILITY
_LIBCPP_CONSTEXPR weak_ptr() _NOEXCEPT;
template<class _Yp> _LIBCPP_INLINE_VISIBILITY weak_ptr(shared_ptr<_Yp> const& __r,
typename enable_if<__compatible_with<_Yp, _Tp>::value, __nat*>::type = 0)
_NOEXCEPT;
_LIBCPP_INLINE_VISIBILITY
weak_ptr(weak_ptr const& __r) _NOEXCEPT;
template<class _Yp> _LIBCPP_INLINE_VISIBILITY weak_ptr(weak_ptr<_Yp> const& __r,
typename enable_if<__compatible_with<_Yp, _Tp>::value, __nat*>::type = 0)
_NOEXCEPT;
_LIBCPP_INLINE_VISIBILITY
weak_ptr(weak_ptr&& __r) _NOEXCEPT;
template<class _Yp> _LIBCPP_INLINE_VISIBILITY weak_ptr(weak_ptr<_Yp>&& __r,
typename enable_if<__compatible_with<_Yp, _Tp>::value, __nat*>::type = 0)
_NOEXCEPT;
~weak_ptr();
_LIBCPP_INLINE_VISIBILITY
weak_ptr& operator=(weak_ptr const& __r) _NOEXCEPT;
template<class _Yp>
typename enable_if
<
__compatible_with<_Yp, _Tp>::value,
weak_ptr&
>::type
_LIBCPP_INLINE_VISIBILITY
operator=(weak_ptr<_Yp> const& __r) _NOEXCEPT;
_LIBCPP_INLINE_VISIBILITY
weak_ptr& operator=(weak_ptr&& __r) _NOEXCEPT;
template<class _Yp>
typename enable_if
<
__compatible_with<_Yp, _Tp>::value,
weak_ptr&
>::type
_LIBCPP_INLINE_VISIBILITY
operator=(weak_ptr<_Yp>&& __r) _NOEXCEPT;
template<class _Yp>
typename enable_if
<
__compatible_with<_Yp, _Tp>::value,
weak_ptr&
>::type
_LIBCPP_INLINE_VISIBILITY
operator=(shared_ptr<_Yp> const& __r) _NOEXCEPT;
_LIBCPP_INLINE_VISIBILITY
void swap(weak_ptr& __r) _NOEXCEPT;
_LIBCPP_INLINE_VISIBILITY
void reset() _NOEXCEPT;
_LIBCPP_INLINE_VISIBILITY
long use_count() const _NOEXCEPT
{return __cntrl_ ? __cntrl_->use_count() : 0;}
_LIBCPP_INLINE_VISIBILITY
bool expired() const _NOEXCEPT
{return __cntrl_ == nullptr || __cntrl_->use_count() == 0;}
shared_ptr<_Tp> lock() const _NOEXCEPT;
template<class _Up>
_LIBCPP_INLINE_VISIBILITY
bool owner_before(const shared_ptr<_Up>& __r) const _NOEXCEPT
{return __cntrl_ < __r.__cntrl_;}
template<class _Up>
_LIBCPP_INLINE_VISIBILITY
bool owner_before(const weak_ptr<_Up>& __r) const _NOEXCEPT
{return __cntrl_ < __r.__cntrl_;}
template <class _Up> friend class _LIBCPP_TEMPLATE_VIS weak_ptr;
template <class _Up> friend class _LIBCPP_TEMPLATE_VIS shared_ptr;
};
#if _LIBCPP_STD_VER > 14
template<class _Tp>
weak_ptr(shared_ptr<_Tp>) -> weak_ptr<_Tp>;
#endif
template<class _Tp>
inline
_LIBCPP_CONSTEXPR
weak_ptr<_Tp>::weak_ptr() _NOEXCEPT
: __ptr_(nullptr),
__cntrl_(nullptr)
{
}
template<class _Tp>
inline
weak_ptr<_Tp>::weak_ptr(weak_ptr const& __r) _NOEXCEPT
: __ptr_(__r.__ptr_),
__cntrl_(__r.__cntrl_)
{
if (__cntrl_)
__cntrl_->__add_weak();
}
template<class _Tp>
template<class _Yp>
inline
weak_ptr<_Tp>::weak_ptr(shared_ptr<_Yp> const& __r,
typename enable_if<__compatible_with<_Yp, _Tp>::value, __nat*>::type)
_NOEXCEPT
: __ptr_(__r.__ptr_),
__cntrl_(__r.__cntrl_)
{
if (__cntrl_)
__cntrl_->__add_weak();
}
template<class _Tp>
template<class _Yp>
inline
weak_ptr<_Tp>::weak_ptr(weak_ptr<_Yp> const& __r,
typename enable_if<__compatible_with<_Yp, _Tp>::value, __nat*>::type)
_NOEXCEPT
: __ptr_(__r.__ptr_),
__cntrl_(__r.__cntrl_)
{
if (__cntrl_)
__cntrl_->__add_weak();
}
template<class _Tp>
inline
weak_ptr<_Tp>::weak_ptr(weak_ptr&& __r) _NOEXCEPT
: __ptr_(__r.__ptr_),
__cntrl_(__r.__cntrl_)
{
__r.__ptr_ = nullptr;
__r.__cntrl_ = nullptr;
}
template<class _Tp>
template<class _Yp>
inline
weak_ptr<_Tp>::weak_ptr(weak_ptr<_Yp>&& __r,
typename enable_if<__compatible_with<_Yp, _Tp>::value, __nat*>::type)
_NOEXCEPT
: __ptr_(__r.__ptr_),
__cntrl_(__r.__cntrl_)
{
__r.__ptr_ = nullptr;
__r.__cntrl_ = nullptr;
}
template<class _Tp>
weak_ptr<_Tp>::~weak_ptr()
{
if (__cntrl_)
__cntrl_->__release_weak();
}
template<class _Tp>
inline
weak_ptr<_Tp>&
weak_ptr<_Tp>::operator=(weak_ptr const& __r) _NOEXCEPT
{
weak_ptr(__r).swap(*this);
return *this;
}
template<class _Tp>
template<class _Yp>
inline
typename enable_if
<
__compatible_with<_Yp, _Tp>::value,
weak_ptr<_Tp>&
>::type
weak_ptr<_Tp>::operator=(weak_ptr<_Yp> const& __r) _NOEXCEPT
{
weak_ptr(__r).swap(*this);
return *this;
}
template<class _Tp>
inline
weak_ptr<_Tp>&
weak_ptr<_Tp>::operator=(weak_ptr&& __r) _NOEXCEPT
{
weak_ptr(_VSTD::move(__r)).swap(*this);
return *this;
}
template<class _Tp>
template<class _Yp>
inline
typename enable_if
<
__compatible_with<_Yp, _Tp>::value,
weak_ptr<_Tp>&
>::type
weak_ptr<_Tp>::operator=(weak_ptr<_Yp>&& __r) _NOEXCEPT
{
weak_ptr(_VSTD::move(__r)).swap(*this);
return *this;
}
template<class _Tp>
template<class _Yp>
inline
typename enable_if
<
__compatible_with<_Yp, _Tp>::value,
weak_ptr<_Tp>&
>::type
weak_ptr<_Tp>::operator=(shared_ptr<_Yp> const& __r) _NOEXCEPT
{
weak_ptr(__r).swap(*this);
return *this;
}
template<class _Tp>
inline
void
weak_ptr<_Tp>::swap(weak_ptr& __r) _NOEXCEPT
{
_VSTD::swap(__ptr_, __r.__ptr_);
_VSTD::swap(__cntrl_, __r.__cntrl_);
}
template<class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
void
swap(weak_ptr<_Tp>& __x, weak_ptr<_Tp>& __y) _NOEXCEPT
{
__x.swap(__y);
}
template<class _Tp>
inline
void
weak_ptr<_Tp>::reset() _NOEXCEPT
{
weak_ptr().swap(*this);
}
template<class _Tp>
shared_ptr<_Tp>
weak_ptr<_Tp>::lock() const _NOEXCEPT
{
shared_ptr<_Tp> __r;
__r.__cntrl_ = __cntrl_ ? __cntrl_->lock() : __cntrl_;
if (__r.__cntrl_)
__r.__ptr_ = __ptr_;
return __r;
}
#if _LIBCPP_STD_VER > 14
template <class _Tp = void> struct owner_less;
#else
template <class _Tp> struct owner_less;
#endif
template <class _Tp>
struct _LIBCPP_TEMPLATE_VIS owner_less<shared_ptr<_Tp> >
: __binary_function<shared_ptr<_Tp>, shared_ptr<_Tp>, bool>
{
_LIBCPP_INLINE_VISIBILITY
bool operator()(shared_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const _NOEXCEPT
{return __x.owner_before(__y);}
_LIBCPP_INLINE_VISIBILITY
bool operator()(shared_ptr<_Tp> const& __x, weak_ptr<_Tp> const& __y) const _NOEXCEPT
{return __x.owner_before(__y);}
_LIBCPP_INLINE_VISIBILITY
bool operator()( weak_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const _NOEXCEPT
{return __x.owner_before(__y);}
};
template <class _Tp>
struct _LIBCPP_TEMPLATE_VIS owner_less<weak_ptr<_Tp> >
: __binary_function<weak_ptr<_Tp>, weak_ptr<_Tp>, bool>
{
_LIBCPP_INLINE_VISIBILITY
bool operator()( weak_ptr<_Tp> const& __x, weak_ptr<_Tp> const& __y) const _NOEXCEPT
{return __x.owner_before(__y);}
_LIBCPP_INLINE_VISIBILITY
bool operator()(shared_ptr<_Tp> const& __x, weak_ptr<_Tp> const& __y) const _NOEXCEPT
{return __x.owner_before(__y);}
_LIBCPP_INLINE_VISIBILITY
bool operator()( weak_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const _NOEXCEPT
{return __x.owner_before(__y);}
};
#if _LIBCPP_STD_VER > 14
template <>
struct _LIBCPP_TEMPLATE_VIS owner_less<void>
{
template <class _Tp, class _Up>
_LIBCPP_INLINE_VISIBILITY
bool operator()( shared_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const _NOEXCEPT
{return __x.owner_before(__y);}
template <class _Tp, class _Up>
_LIBCPP_INLINE_VISIBILITY
bool operator()( shared_ptr<_Tp> const& __x, weak_ptr<_Up> const& __y) const _NOEXCEPT
{return __x.owner_before(__y);}
template <class _Tp, class _Up>
_LIBCPP_INLINE_VISIBILITY
bool operator()( weak_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const _NOEXCEPT
{return __x.owner_before(__y);}
template <class _Tp, class _Up>
_LIBCPP_INLINE_VISIBILITY
bool operator()( weak_ptr<_Tp> const& __x, weak_ptr<_Up> const& __y) const _NOEXCEPT
{return __x.owner_before(__y);}
typedef void is_transparent;
};
#endif
template<class _Tp>
class _LIBCPP_TEMPLATE_VIS enable_shared_from_this
{
mutable weak_ptr<_Tp> __weak_this_;
protected:
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
enable_shared_from_this() _NOEXCEPT {}
_LIBCPP_INLINE_VISIBILITY
enable_shared_from_this(enable_shared_from_this const&) _NOEXCEPT {}
_LIBCPP_INLINE_VISIBILITY
enable_shared_from_this& operator=(enable_shared_from_this const&) _NOEXCEPT
{return *this;}
_LIBCPP_INLINE_VISIBILITY
~enable_shared_from_this() {}
public:
_LIBCPP_INLINE_VISIBILITY
shared_ptr<_Tp> shared_from_this()
{return shared_ptr<_Tp>(__weak_this_);}
_LIBCPP_INLINE_VISIBILITY
shared_ptr<_Tp const> shared_from_this() const
{return shared_ptr<const _Tp>(__weak_this_);}
#if _LIBCPP_STD_VER > 14
_LIBCPP_INLINE_VISIBILITY
weak_ptr<_Tp> weak_from_this() _NOEXCEPT
{ return __weak_this_; }
_LIBCPP_INLINE_VISIBILITY
weak_ptr<const _Tp> weak_from_this() const _NOEXCEPT
{ return __weak_this_; }
#endif // _LIBCPP_STD_VER > 14
template <class _Up> friend class shared_ptr;
};
template <class _Tp> struct _LIBCPP_TEMPLATE_VIS hash;
template <class _Tp>
struct _LIBCPP_TEMPLATE_VIS hash<shared_ptr<_Tp> >
{
#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
_LIBCPP_DEPRECATED_IN_CXX17 typedef shared_ptr<_Tp> argument_type;
_LIBCPP_DEPRECATED_IN_CXX17 typedef size_t result_type;
#endif
_LIBCPP_INLINE_VISIBILITY
size_t operator()(const shared_ptr<_Tp>& __ptr) const _NOEXCEPT
{
return hash<typename shared_ptr<_Tp>::element_type*>()(__ptr.get());
}
};
template<class _CharT, class _Traits, class _Yp>
inline _LIBCPP_INLINE_VISIBILITY
basic_ostream<_CharT, _Traits>&
operator<<(basic_ostream<_CharT, _Traits>& __os, shared_ptr<_Yp> const& __p);
#if !defined(_LIBCPP_HAS_NO_THREADS)
class _LIBCPP_TYPE_VIS __sp_mut
{
void* __lx_;
public:
void lock() _NOEXCEPT;
void unlock() _NOEXCEPT;
private:
_LIBCPP_CONSTEXPR __sp_mut(void*) _NOEXCEPT;
__sp_mut(const __sp_mut&);
__sp_mut& operator=(const __sp_mut&);
friend _LIBCPP_FUNC_VIS __sp_mut& __get_sp_mut(const void*);
};
_LIBCPP_FUNC_VIS _LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
__sp_mut& __get_sp_mut(const void*);
template <class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
bool
atomic_is_lock_free(const shared_ptr<_Tp>*)
{
return false;
}
template <class _Tp>
_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp>
atomic_load(const shared_ptr<_Tp>* __p)
{
__sp_mut& __m = std::__get_sp_mut(__p);
__m.lock();
shared_ptr<_Tp> __q = *__p;
__m.unlock();
return __q;
}
template <class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
shared_ptr<_Tp>
atomic_load_explicit(const shared_ptr<_Tp>* __p, memory_order)
{
return std::atomic_load(__p);
}
template <class _Tp>
_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
_LIBCPP_HIDE_FROM_ABI void
atomic_store(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r)
{
__sp_mut& __m = std::__get_sp_mut(__p);
__m.lock();
__p->swap(__r);
__m.unlock();
}
template <class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
void
atomic_store_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r, memory_order)
{
std::atomic_store(__p, __r);
}
template <class _Tp>
_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
_LIBCPP_HIDE_FROM_ABI shared_ptr<_Tp>
atomic_exchange(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r)
{
__sp_mut& __m = std::__get_sp_mut(__p);
__m.lock();
__p->swap(__r);
__m.unlock();
return __r;
}
template <class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
shared_ptr<_Tp>
atomic_exchange_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r, memory_order)
{
return std::atomic_exchange(__p, __r);
}
template <class _Tp>
_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
_LIBCPP_HIDE_FROM_ABI bool
atomic_compare_exchange_strong(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v, shared_ptr<_Tp> __w)
{
shared_ptr<_Tp> __temp;
__sp_mut& __m = std::__get_sp_mut(__p);
__m.lock();
if (__p->__owner_equivalent(*__v))
{
_VSTD::swap(__temp, *__p);
*__p = __w;
__m.unlock();
return true;
}
_VSTD::swap(__temp, *__v);
*__v = *__p;
__m.unlock();
return false;
}
template <class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
bool
atomic_compare_exchange_weak(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v, shared_ptr<_Tp> __w)
{
return std::atomic_compare_exchange_strong(__p, __v, __w);
}
template <class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
bool
atomic_compare_exchange_strong_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v,
shared_ptr<_Tp> __w, memory_order, memory_order)
{
return std::atomic_compare_exchange_strong(__p, __v, __w);
}
template <class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
bool
atomic_compare_exchange_weak_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v,
shared_ptr<_Tp> __w, memory_order, memory_order)
{
return std::atomic_compare_exchange_weak(__p, __v, __w);
}
#endif // !defined(_LIBCPP_HAS_NO_THREADS)
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___MEMORY_SHARED_PTR_H