af181c91a9
* include/bits/shared_ptr.h (shared_ptr, weak_ptr): Add deduction guides for C++17. * include/bits/std_function.h (function): Likewise. * include/bits/stl_pair.h (pair): Likewise. * include/debug/array (__gnu_debug::array): Likewise. * include/std/array (array): Likewise. * include/std/functional (make_default_searcher) (make_boyer_moore_searcher, make_boyer_moore_horspool_searcher): Remove generator functions. * include/std/tuple (tuple): Add deduction guides. * include/std/valarray (valarray): Likewise. * testsuite/20_util/function_objects/searchers.cc: Adjust to use class template argument deduction instead of generator functions. * testsuite/20_util/function/cons/deduction.cc: New test. * testsuite/20_util/optional/cons/deduction_guide.cc: Rename to ... * testsuite/20_util/optional/cons/deduction.cc: ... here. * testsuite/20_util/pair/cons/deduction.cc: New test. * testsuite/20_util/shared_ptr/cons/deduction.cc: New test. * testsuite/20_util/tuple/cons/deduction.cc: New test. * testsuite/20_util/tuple/element_access/get_neg.cc: Adjust dg-error. * testsuite/20_util/unique_ptr/cons/deduction_neg.cc: New test. * testsuite/20_util/weak_ptr/cons/deduction.cc: New test. * testsuite/23_containers/array/cons/deduction.cc: New test. * testsuite/23_containers/array/cons/deduction_neg.cc: New test. * testsuite/23_containers/array/tuple_interface/get_debug_neg.cc: Adjust dg-error. * testsuite/23_containers/array/tuple_interface/get_neg.cc: Likewise. * testsuite/23_containers/array/tuple_interface/tuple_element_neg.cc: Likewise. * testsuite/26_numerics/valarray/deduction.cc: New test. * testsuite/30_threads/lock_guard/cons/deduction.cc: New test. * testsuite/30_threads/scoped_lock/cons/deduction.cc: New test. * testsuite/30_threads/unique_lock/cons/deduction.cc: New test. From-SVN: r246389
728 lines
22 KiB
C++
728 lines
22 KiB
C++
// shared_ptr and weak_ptr implementation -*- C++ -*-
|
|
|
|
// Copyright (C) 2007-2017 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/>.
|
|
|
|
// GCC Note: Based on files from version 1.32.0 of the Boost library.
|
|
|
|
// shared_count.hpp
|
|
// Copyright (c) 2001, 2002, 2003 Peter Dimov and Multi Media Ltd.
|
|
|
|
// shared_ptr.hpp
|
|
// Copyright (C) 1998, 1999 Greg Colvin and Beman Dawes.
|
|
// Copyright (C) 2001, 2002, 2003 Peter Dimov
|
|
|
|
// weak_ptr.hpp
|
|
// Copyright (C) 2001, 2002, 2003 Peter Dimov
|
|
|
|
// enable_shared_from_this.hpp
|
|
// Copyright (C) 2002 Peter Dimov
|
|
|
|
// Distributed under the Boost Software License, Version 1.0. (See
|
|
// accompanying file LICENSE_1_0.txt or copy at
|
|
// http://www.boost.org/LICENSE_1_0.txt)
|
|
|
|
/** @file
|
|
* This is an internal header file, included by other library headers.
|
|
* Do not attempt to use it directly. @headername{memory}
|
|
*/
|
|
|
|
#ifndef _SHARED_PTR_H
|
|
#define _SHARED_PTR_H 1
|
|
|
|
#include <bits/shared_ptr_base.h>
|
|
|
|
namespace std _GLIBCXX_VISIBILITY(default)
|
|
{
|
|
_GLIBCXX_BEGIN_NAMESPACE_VERSION
|
|
|
|
/**
|
|
* @addtogroup pointer_abstractions
|
|
* @{
|
|
*/
|
|
|
|
/// 20.7.2.2.11 shared_ptr I/O
|
|
template<typename _Ch, typename _Tr, typename _Tp, _Lock_policy _Lp>
|
|
inline std::basic_ostream<_Ch, _Tr>&
|
|
operator<<(std::basic_ostream<_Ch, _Tr>& __os,
|
|
const __shared_ptr<_Tp, _Lp>& __p)
|
|
{
|
|
__os << __p.get();
|
|
return __os;
|
|
}
|
|
|
|
/// 20.7.2.2.10 shared_ptr get_deleter
|
|
template<typename _Del, typename _Tp, _Lock_policy _Lp>
|
|
inline _Del*
|
|
get_deleter(const __shared_ptr<_Tp, _Lp>& __p) noexcept
|
|
{
|
|
#if __cpp_rtti
|
|
return static_cast<_Del*>(__p._M_get_deleter(typeid(_Del)));
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
|
|
/**
|
|
* @brief A smart pointer with reference-counted copy semantics.
|
|
*
|
|
* The object pointed to is deleted when the last shared_ptr pointing to
|
|
* it is destroyed or reset.
|
|
*/
|
|
template<typename _Tp>
|
|
class shared_ptr : public __shared_ptr<_Tp>
|
|
{
|
|
template<typename... _Args>
|
|
using _Constructible = typename enable_if<
|
|
is_constructible<__shared_ptr<_Tp>, _Args...>::value
|
|
>::type;
|
|
|
|
template<typename _Arg>
|
|
using _Assignable = typename enable_if<
|
|
is_assignable<__shared_ptr<_Tp>&, _Arg>::value, shared_ptr&
|
|
>::type;
|
|
|
|
public:
|
|
|
|
using element_type = typename __shared_ptr<_Tp>::element_type;
|
|
|
|
#if __cplusplus > 201402L
|
|
# define __cpp_lib_shared_ptr_weak_type 201606
|
|
using weak_type = weak_ptr<_Tp>;
|
|
#endif
|
|
/**
|
|
* @brief Construct an empty %shared_ptr.
|
|
* @post use_count()==0 && get()==0
|
|
*/
|
|
constexpr shared_ptr() noexcept : __shared_ptr<_Tp>() { }
|
|
|
|
shared_ptr(const shared_ptr&) noexcept = default;
|
|
|
|
/**
|
|
* @brief Construct a %shared_ptr that owns the pointer @a __p.
|
|
* @param __p A pointer that is convertible to element_type*.
|
|
* @post use_count() == 1 && get() == __p
|
|
* @throw std::bad_alloc, in which case @c delete @a __p is called.
|
|
*/
|
|
template<typename _Yp, typename = _Constructible<_Yp*>>
|
|
explicit
|
|
shared_ptr(_Yp* __p) : __shared_ptr<_Tp>(__p) { }
|
|
|
|
/**
|
|
* @brief Construct a %shared_ptr that owns the pointer @a __p
|
|
* and the deleter @a __d.
|
|
* @param __p A pointer.
|
|
* @param __d A deleter.
|
|
* @post use_count() == 1 && get() == __p
|
|
* @throw std::bad_alloc, in which case @a __d(__p) is called.
|
|
*
|
|
* Requirements: _Deleter's copy constructor and destructor must
|
|
* not throw
|
|
*
|
|
* __shared_ptr will release __p by calling __d(__p)
|
|
*/
|
|
template<typename _Yp, typename _Deleter,
|
|
typename = _Constructible<_Yp*, _Deleter>>
|
|
shared_ptr(_Yp* __p, _Deleter __d)
|
|
: __shared_ptr<_Tp>(__p, __d) { }
|
|
|
|
/**
|
|
* @brief Construct a %shared_ptr that owns a null pointer
|
|
* and the deleter @a __d.
|
|
* @param __p A null pointer constant.
|
|
* @param __d A deleter.
|
|
* @post use_count() == 1 && get() == __p
|
|
* @throw std::bad_alloc, in which case @a __d(__p) is called.
|
|
*
|
|
* Requirements: _Deleter's copy constructor and destructor must
|
|
* not throw
|
|
*
|
|
* The last owner will call __d(__p)
|
|
*/
|
|
template<typename _Deleter>
|
|
shared_ptr(nullptr_t __p, _Deleter __d)
|
|
: __shared_ptr<_Tp>(__p, __d) { }
|
|
|
|
/**
|
|
* @brief Construct a %shared_ptr that owns the pointer @a __p
|
|
* and the deleter @a __d.
|
|
* @param __p A pointer.
|
|
* @param __d A deleter.
|
|
* @param __a An allocator.
|
|
* @post use_count() == 1 && get() == __p
|
|
* @throw std::bad_alloc, in which case @a __d(__p) is called.
|
|
*
|
|
* Requirements: _Deleter's copy constructor and destructor must
|
|
* not throw _Alloc's copy constructor and destructor must not
|
|
* throw.
|
|
*
|
|
* __shared_ptr will release __p by calling __d(__p)
|
|
*/
|
|
template<typename _Yp, typename _Deleter, typename _Alloc,
|
|
typename = _Constructible<_Yp*, _Deleter, _Alloc>>
|
|
shared_ptr(_Yp* __p, _Deleter __d, _Alloc __a)
|
|
: __shared_ptr<_Tp>(__p, __d, std::move(__a)) { }
|
|
|
|
/**
|
|
* @brief Construct a %shared_ptr that owns a null pointer
|
|
* and the deleter @a __d.
|
|
* @param __p A null pointer constant.
|
|
* @param __d A deleter.
|
|
* @param __a An allocator.
|
|
* @post use_count() == 1 && get() == __p
|
|
* @throw std::bad_alloc, in which case @a __d(__p) is called.
|
|
*
|
|
* Requirements: _Deleter's copy constructor and destructor must
|
|
* not throw _Alloc's copy constructor and destructor must not
|
|
* throw.
|
|
*
|
|
* The last owner will call __d(__p)
|
|
*/
|
|
template<typename _Deleter, typename _Alloc>
|
|
shared_ptr(nullptr_t __p, _Deleter __d, _Alloc __a)
|
|
: __shared_ptr<_Tp>(__p, __d, std::move(__a)) { }
|
|
|
|
// Aliasing constructor
|
|
|
|
/**
|
|
* @brief Constructs a %shared_ptr instance that stores @a __p
|
|
* and shares ownership with @a __r.
|
|
* @param __r A %shared_ptr.
|
|
* @param __p A pointer that will remain valid while @a *__r is valid.
|
|
* @post get() == __p && use_count() == __r.use_count()
|
|
*
|
|
* This can be used to construct a @c shared_ptr to a sub-object
|
|
* of an object managed by an existing @c shared_ptr.
|
|
*
|
|
* @code
|
|
* shared_ptr< pair<int,int> > pii(new pair<int,int>());
|
|
* shared_ptr<int> pi(pii, &pii->first);
|
|
* assert(pii.use_count() == 2);
|
|
* @endcode
|
|
*/
|
|
template<typename _Yp>
|
|
shared_ptr(const shared_ptr<_Yp>& __r, element_type* __p) noexcept
|
|
: __shared_ptr<_Tp>(__r, __p) { }
|
|
|
|
/**
|
|
* @brief If @a __r is empty, constructs an empty %shared_ptr;
|
|
* otherwise construct a %shared_ptr that shares ownership
|
|
* with @a __r.
|
|
* @param __r A %shared_ptr.
|
|
* @post get() == __r.get() && use_count() == __r.use_count()
|
|
*/
|
|
template<typename _Yp,
|
|
typename = _Constructible<const shared_ptr<_Yp>&>>
|
|
shared_ptr(const shared_ptr<_Yp>& __r) noexcept
|
|
: __shared_ptr<_Tp>(__r) { }
|
|
|
|
/**
|
|
* @brief Move-constructs a %shared_ptr instance from @a __r.
|
|
* @param __r A %shared_ptr rvalue.
|
|
* @post *this contains the old value of @a __r, @a __r is empty.
|
|
*/
|
|
shared_ptr(shared_ptr&& __r) noexcept
|
|
: __shared_ptr<_Tp>(std::move(__r)) { }
|
|
|
|
/**
|
|
* @brief Move-constructs a %shared_ptr instance from @a __r.
|
|
* @param __r A %shared_ptr rvalue.
|
|
* @post *this contains the old value of @a __r, @a __r is empty.
|
|
*/
|
|
template<typename _Yp, typename = _Constructible<shared_ptr<_Yp>>>
|
|
shared_ptr(shared_ptr<_Yp>&& __r) noexcept
|
|
: __shared_ptr<_Tp>(std::move(__r)) { }
|
|
|
|
/**
|
|
* @brief Constructs a %shared_ptr that shares ownership with @a __r
|
|
* and stores a copy of the pointer stored in @a __r.
|
|
* @param __r A weak_ptr.
|
|
* @post use_count() == __r.use_count()
|
|
* @throw bad_weak_ptr when __r.expired(),
|
|
* in which case the constructor has no effect.
|
|
*/
|
|
template<typename _Yp, typename = _Constructible<const weak_ptr<_Yp>&>>
|
|
explicit shared_ptr(const weak_ptr<_Yp>& __r)
|
|
: __shared_ptr<_Tp>(__r) { }
|
|
|
|
#if _GLIBCXX_USE_DEPRECATED
|
|
template<typename _Yp, typename = _Constructible<auto_ptr<_Yp>>>
|
|
shared_ptr(auto_ptr<_Yp>&& __r);
|
|
#endif
|
|
|
|
// _GLIBCXX_RESOLVE_LIB_DEFECTS
|
|
// 2399. shared_ptr's constructor from unique_ptr should be constrained
|
|
template<typename _Yp, typename _Del,
|
|
typename = _Constructible<unique_ptr<_Yp, _Del>>>
|
|
shared_ptr(unique_ptr<_Yp, _Del>&& __r)
|
|
: __shared_ptr<_Tp>(std::move(__r)) { }
|
|
|
|
#if __cplusplus <= 201402L && _GLIBCXX_USE_DEPRECATED
|
|
// This non-standard constructor exists to support conversions that
|
|
// were possible in C++11 and C++14 but are ill-formed in C++17.
|
|
// If an exception is thrown this constructor has no effect.
|
|
template<typename _Yp, typename _Del,
|
|
_Constructible<unique_ptr<_Yp, _Del>, __sp_array_delete>* = 0>
|
|
shared_ptr(unique_ptr<_Yp, _Del>&& __r)
|
|
: __shared_ptr<_Tp>(std::move(__r), __sp_array_delete()) { }
|
|
#endif
|
|
|
|
/**
|
|
* @brief Construct an empty %shared_ptr.
|
|
* @post use_count() == 0 && get() == nullptr
|
|
*/
|
|
constexpr shared_ptr(nullptr_t) noexcept : shared_ptr() { }
|
|
|
|
shared_ptr& operator=(const shared_ptr&) noexcept = default;
|
|
|
|
template<typename _Yp>
|
|
_Assignable<const shared_ptr<_Yp>&>
|
|
operator=(const shared_ptr<_Yp>& __r) noexcept
|
|
{
|
|
this->__shared_ptr<_Tp>::operator=(__r);
|
|
return *this;
|
|
}
|
|
|
|
#if _GLIBCXX_USE_DEPRECATED
|
|
template<typename _Yp>
|
|
_Assignable<auto_ptr<_Yp>>
|
|
operator=(auto_ptr<_Yp>&& __r)
|
|
{
|
|
this->__shared_ptr<_Tp>::operator=(std::move(__r));
|
|
return *this;
|
|
}
|
|
#endif
|
|
|
|
shared_ptr&
|
|
operator=(shared_ptr&& __r) noexcept
|
|
{
|
|
this->__shared_ptr<_Tp>::operator=(std::move(__r));
|
|
return *this;
|
|
}
|
|
|
|
template<class _Yp>
|
|
_Assignable<shared_ptr<_Yp>>
|
|
operator=(shared_ptr<_Yp>&& __r) noexcept
|
|
{
|
|
this->__shared_ptr<_Tp>::operator=(std::move(__r));
|
|
return *this;
|
|
}
|
|
|
|
template<typename _Yp, typename _Del>
|
|
_Assignable<unique_ptr<_Yp, _Del>>
|
|
operator=(unique_ptr<_Yp, _Del>&& __r)
|
|
{
|
|
this->__shared_ptr<_Tp>::operator=(std::move(__r));
|
|
return *this;
|
|
}
|
|
|
|
private:
|
|
// This constructor is non-standard, it is used by allocate_shared.
|
|
template<typename _Alloc, typename... _Args>
|
|
shared_ptr(_Sp_make_shared_tag __tag, const _Alloc& __a,
|
|
_Args&&... __args)
|
|
: __shared_ptr<_Tp>(__tag, __a, std::forward<_Args>(__args)...)
|
|
{ }
|
|
|
|
template<typename _Yp, typename _Alloc, typename... _Args>
|
|
friend shared_ptr<_Yp>
|
|
allocate_shared(const _Alloc& __a, _Args&&... __args);
|
|
|
|
// This constructor is non-standard, it is used by weak_ptr::lock().
|
|
shared_ptr(const weak_ptr<_Tp>& __r, std::nothrow_t)
|
|
: __shared_ptr<_Tp>(__r, std::nothrow) { }
|
|
|
|
friend class weak_ptr<_Tp>;
|
|
};
|
|
|
|
#if __cpp_deduction_guides >= 201606
|
|
template<typename _Tp>
|
|
shared_ptr(weak_ptr<_Tp>) -> shared_ptr<_Tp>;
|
|
template<typename _Tp, typename _Del>
|
|
shared_ptr(unique_ptr<_Tp, _Del>) -> shared_ptr<_Tp>;
|
|
#endif
|
|
|
|
// 20.7.2.2.7 shared_ptr comparisons
|
|
template<typename _Tp, typename _Up>
|
|
inline bool
|
|
operator==(const shared_ptr<_Tp>& __a, const shared_ptr<_Up>& __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 _Tp, typename _Up>
|
|
inline bool
|
|
operator!=(const shared_ptr<_Tp>& __a, const shared_ptr<_Up>& __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 _Tp, typename _Up>
|
|
inline bool
|
|
operator<(const shared_ptr<_Tp>& __a, const shared_ptr<_Up>& __b) noexcept
|
|
{
|
|
using _Tp_elt = typename shared_ptr<_Tp>::element_type;
|
|
using _Up_elt = typename shared_ptr<_Up>::element_type;
|
|
using _Vp = typename common_type<_Tp_elt*, _Up_elt*>::type;
|
|
return less<_Vp>()(__a.get(), __b.get());
|
|
}
|
|
|
|
template<typename _Tp>
|
|
inline bool
|
|
operator<(const shared_ptr<_Tp>& __a, nullptr_t) noexcept
|
|
{
|
|
using _Tp_elt = typename shared_ptr<_Tp>::element_type;
|
|
return less<_Tp_elt*>()(__a.get(), nullptr);
|
|
}
|
|
|
|
template<typename _Tp>
|
|
inline bool
|
|
operator<(nullptr_t, const shared_ptr<_Tp>& __a) noexcept
|
|
{
|
|
using _Tp_elt = typename shared_ptr<_Tp>::element_type;
|
|
return less<_Tp_elt*>()(nullptr, __a.get());
|
|
}
|
|
|
|
template<typename _Tp, typename _Up>
|
|
inline bool
|
|
operator<=(const shared_ptr<_Tp>& __a, const shared_ptr<_Up>& __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 _Tp, typename _Up>
|
|
inline bool
|
|
operator>(const shared_ptr<_Tp>& __a, const shared_ptr<_Up>& __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 _Tp, typename _Up>
|
|
inline bool
|
|
operator>=(const shared_ptr<_Tp>& __a, const shared_ptr<_Up>& __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); }
|
|
|
|
template<typename _Tp>
|
|
struct less<shared_ptr<_Tp>> : public _Sp_less<shared_ptr<_Tp>>
|
|
{ };
|
|
|
|
// 20.7.2.2.8 shared_ptr specialized algorithms.
|
|
template<typename _Tp>
|
|
inline void
|
|
swap(shared_ptr<_Tp>& __a, shared_ptr<_Tp>& __b) noexcept
|
|
{ __a.swap(__b); }
|
|
|
|
// 20.7.2.2.9 shared_ptr casts.
|
|
template<typename _Tp, typename _Up>
|
|
inline shared_ptr<_Tp>
|
|
static_pointer_cast(const shared_ptr<_Up>& __r) noexcept
|
|
{
|
|
using _Sp = shared_ptr<_Tp>;
|
|
return _Sp(__r, static_cast<typename _Sp::element_type*>(__r.get()));
|
|
}
|
|
|
|
template<typename _Tp, typename _Up>
|
|
inline shared_ptr<_Tp>
|
|
const_pointer_cast(const shared_ptr<_Up>& __r) noexcept
|
|
{
|
|
using _Sp = shared_ptr<_Tp>;
|
|
return _Sp(__r, const_cast<typename _Sp::element_type*>(__r.get()));
|
|
}
|
|
|
|
template<typename _Tp, typename _Up>
|
|
inline shared_ptr<_Tp>
|
|
dynamic_pointer_cast(const shared_ptr<_Up>& __r) noexcept
|
|
{
|
|
using _Sp = shared_ptr<_Tp>;
|
|
if (auto* __p = dynamic_cast<typename _Sp::element_type*>(__r.get()))
|
|
return _Sp(__r, __p);
|
|
return _Sp();
|
|
}
|
|
|
|
#if __cplusplus > 201402L
|
|
template<typename _Tp, typename _Up>
|
|
inline shared_ptr<_Tp>
|
|
reinterpret_pointer_cast(const shared_ptr<_Up>& __r) noexcept
|
|
{
|
|
using _Sp = shared_ptr<_Tp>;
|
|
return _Sp(__r, reinterpret_cast<typename _Sp::element_type*>(__r.get()));
|
|
}
|
|
#endif
|
|
|
|
/**
|
|
* @brief A smart pointer with weak semantics.
|
|
*
|
|
* With forwarding constructors and assignment operators.
|
|
*/
|
|
template<typename _Tp>
|
|
class weak_ptr : public __weak_ptr<_Tp>
|
|
{
|
|
template<typename _Arg>
|
|
using _Constructible = typename enable_if<
|
|
is_constructible<__weak_ptr<_Tp>, _Arg>::value
|
|
>::type;
|
|
|
|
template<typename _Arg>
|
|
using _Assignable = typename enable_if<
|
|
is_assignable<__weak_ptr<_Tp>&, _Arg>::value, weak_ptr&
|
|
>::type;
|
|
|
|
public:
|
|
constexpr weak_ptr() noexcept = default;
|
|
|
|
template<typename _Yp,
|
|
typename = _Constructible<const shared_ptr<_Yp>&>>
|
|
weak_ptr(const shared_ptr<_Yp>& __r) noexcept
|
|
: __weak_ptr<_Tp>(__r) { }
|
|
|
|
weak_ptr(const weak_ptr&) noexcept = default;
|
|
|
|
template<typename _Yp, typename = _Constructible<const weak_ptr<_Yp>&>>
|
|
weak_ptr(const weak_ptr<_Yp>& __r) noexcept
|
|
: __weak_ptr<_Tp>(__r) { }
|
|
|
|
weak_ptr(weak_ptr&&) noexcept = default;
|
|
|
|
template<typename _Yp, typename = _Constructible<weak_ptr<_Yp>>>
|
|
weak_ptr(weak_ptr<_Yp>&& __r) noexcept
|
|
: __weak_ptr<_Tp>(std::move(__r)) { }
|
|
|
|
weak_ptr&
|
|
operator=(const weak_ptr& __r) noexcept = default;
|
|
|
|
template<typename _Yp>
|
|
_Assignable<const weak_ptr<_Yp>&>
|
|
operator=(const weak_ptr<_Yp>& __r) noexcept
|
|
{
|
|
this->__weak_ptr<_Tp>::operator=(__r);
|
|
return *this;
|
|
}
|
|
|
|
template<typename _Yp>
|
|
_Assignable<const shared_ptr<_Yp>&>
|
|
operator=(const shared_ptr<_Yp>& __r) noexcept
|
|
{
|
|
this->__weak_ptr<_Tp>::operator=(__r);
|
|
return *this;
|
|
}
|
|
|
|
weak_ptr&
|
|
operator=(weak_ptr&& __r) noexcept = default;
|
|
|
|
template<typename _Yp>
|
|
_Assignable<weak_ptr<_Yp>>
|
|
operator=(weak_ptr<_Yp>&& __r) noexcept
|
|
{
|
|
this->__weak_ptr<_Tp>::operator=(std::move(__r));
|
|
return *this;
|
|
}
|
|
|
|
shared_ptr<_Tp>
|
|
lock() const noexcept
|
|
{ return shared_ptr<_Tp>(*this, std::nothrow); }
|
|
};
|
|
|
|
#if __cpp_deduction_guides >= 201606
|
|
template<typename _Tp>
|
|
weak_ptr(shared_ptr<_Tp>) -> weak_ptr<_Tp>;
|
|
#endif
|
|
|
|
// 20.7.2.3.6 weak_ptr specialized algorithms.
|
|
template<typename _Tp>
|
|
inline void
|
|
swap(weak_ptr<_Tp>& __a, weak_ptr<_Tp>& __b) noexcept
|
|
{ __a.swap(__b); }
|
|
|
|
|
|
/// Primary template owner_less
|
|
template<typename _Tp = void>
|
|
struct owner_less;
|
|
|
|
/// Void specialization of owner_less
|
|
template<>
|
|
struct owner_less<void> : _Sp_owner_less<void, void>
|
|
{ };
|
|
|
|
/// 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>>
|
|
{ };
|
|
|
|
/**
|
|
* @brief Base class allowing use of member function 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); }
|
|
|
|
#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
|
|
#define __cpp_lib_enable_shared_from_this 201603
|
|
weak_ptr<_Tp>
|
|
weak_from_this() noexcept
|
|
{ return this->_M_weak_this; }
|
|
|
|
weak_ptr<const _Tp>
|
|
weak_from_this() const noexcept
|
|
{ return this->_M_weak_this; }
|
|
#endif
|
|
|
|
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*
|
|
__enable_shared_from_this_base(const __shared_count<>&,
|
|
const enable_shared_from_this* __p)
|
|
{ return __p; }
|
|
|
|
template<typename, _Lock_policy>
|
|
friend class __shared_ptr;
|
|
|
|
mutable weak_ptr<_Tp> _M_weak_this;
|
|
};
|
|
|
|
/**
|
|
* @brief Create an object that is owned by a shared_ptr.
|
|
* @param __a An allocator.
|
|
* @param __args Arguments for the @a _Tp object's constructor.
|
|
* @return A shared_ptr that owns the newly created object.
|
|
* @throw An exception thrown from @a _Alloc::allocate or from the
|
|
* constructor of @a _Tp.
|
|
*
|
|
* A copy of @a __a will be used to allocate memory for the shared_ptr
|
|
* and the new object.
|
|
*/
|
|
template<typename _Tp, typename _Alloc, typename... _Args>
|
|
inline shared_ptr<_Tp>
|
|
allocate_shared(const _Alloc& __a, _Args&&... __args)
|
|
{
|
|
return shared_ptr<_Tp>(_Sp_make_shared_tag(), __a,
|
|
std::forward<_Args>(__args)...);
|
|
}
|
|
|
|
/**
|
|
* @brief Create an object that is owned by a shared_ptr.
|
|
* @param __args Arguments for the @a _Tp object's constructor.
|
|
* @return A shared_ptr that owns the newly created object.
|
|
* @throw std::bad_alloc, or an exception thrown from the
|
|
* constructor of @a _Tp.
|
|
*/
|
|
template<typename _Tp, typename... _Args>
|
|
inline shared_ptr<_Tp>
|
|
make_shared(_Args&&... __args)
|
|
{
|
|
typedef typename std::remove_const<_Tp>::type _Tp_nc;
|
|
return std::allocate_shared<_Tp>(std::allocator<_Tp_nc>(),
|
|
std::forward<_Args>(__args)...);
|
|
}
|
|
|
|
/// std::hash specialization for shared_ptr.
|
|
template<typename _Tp>
|
|
struct hash<shared_ptr<_Tp>>
|
|
: public __hash_base<size_t, shared_ptr<_Tp>>
|
|
{
|
|
size_t
|
|
operator()(const shared_ptr<_Tp>& __s) const noexcept
|
|
{
|
|
return std::hash<typename shared_ptr<_Tp>::element_type*>()(__s.get());
|
|
}
|
|
};
|
|
|
|
// @} group pointer_abstractions
|
|
|
|
_GLIBCXX_END_NAMESPACE_VERSION
|
|
} // namespace
|
|
|
|
#endif // _SHARED_PTR_H
|