unique_ptr.h
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// unique_ptr implementation -*- C++ -*-
// Copyright (C) 2008-2025 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 bits/unique_ptr.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{memory}
*/
#ifndef _UNIQUE_PTR_H
#define _UNIQUE_PTR_H 1
#include <bits/c++config.h>
#include <debug/assertions.h>
#include <type_traits>
#include <tuple>
#include <bits/stl_function.h>
#include <bits/functional_hash.h>
#if __cplusplus >= 202002L
# include <compare>
# if _GLIBCXX_HOSTED
# include <bits/ostream.h>
# endif
#endif
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/**
* @addtogroup pointer_abstractions
* @{
*/
#if _GLIBCXX_USE_DEPRECATED
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
template<typename> class auto_ptr;
#pragma GCC diagnostic pop
#endif
/** Primary template of default_delete, used by unique_ptr for single objects
*
* @headerfile memory
* @since C++11
*/
template<typename _Tp>
struct default_delete
{
/// Default constructor
constexpr default_delete() noexcept = default;
/** @brief Converting constructor.
*
* Allows conversion from a deleter for objects of another type, `_Up`,
* only if `_Up*` is convertible to `_Tp*`.
*/
template<typename _Up,
typename = _Require<is_convertible<_Up*, _Tp*>>>
_GLIBCXX23_CONSTEXPR
default_delete(const default_delete<_Up>&) noexcept { }
/// Calls `delete __ptr`
_GLIBCXX23_CONSTEXPR
void
operator()(_Tp* __ptr) const
{
static_assert(!is_void<_Tp>::value,
"can't delete pointer to incomplete type");
static_assert(sizeof(_Tp)>0,
"can't delete pointer to incomplete type");
delete __ptr;
}
};
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// DR 740 - omit specialization for array objects with a compile time length
/** Specialization of default_delete for arrays, used by `unique_ptr<T[]>`
*
* @headerfile memory
* @since C++11
*/
template<typename _Tp>
struct default_delete<_Tp[]>
{
public:
/// Default constructor
constexpr default_delete() noexcept = default;
/** @brief Converting constructor.
*
* Allows conversion from a deleter for arrays of another type, such as
* a const-qualified version of `_Tp`.
*
* Conversions from types derived from `_Tp` are not allowed because
* it is undefined to `delete[]` an array of derived types through a
* pointer to the base type.
*/
template<typename _Up,
typename = _Require<is_convertible<_Up(*)[], _Tp(*)[]>>>
_GLIBCXX23_CONSTEXPR
default_delete(const default_delete<_Up[]>&) noexcept { }
/// Calls `delete[] __ptr`
template<typename _Up>
_GLIBCXX23_CONSTEXPR
typename enable_if<is_convertible<_Up(*)[], _Tp(*)[]>::value>::type
operator()(_Up* __ptr) const
{
static_assert(sizeof(_Tp)>0,
"can't delete pointer to incomplete type");
delete [] __ptr;
}
};
/// @cond undocumented
// Manages the pointer and deleter of a unique_ptr
template <typename _Tp, typename _Dp>
class __uniq_ptr_impl
{
template <typename _Up, typename _Ep, typename = void>
struct _Ptr
{
using type = _Up*;
};
template <typename _Up, typename _Ep>
struct
_Ptr<_Up, _Ep, __void_t<typename remove_reference<_Ep>::type::pointer>>
{
using type = typename remove_reference<_Ep>::type::pointer;
};
public:
using _DeleterConstraint = enable_if<
__and_<__not_<is_pointer<_Dp>>,
is_default_constructible<_Dp>>::value>;
using pointer = typename _Ptr<_Tp, _Dp>::type;
static_assert( !is_rvalue_reference<_Dp>::value,
"unique_ptr's deleter type must be a function object type"
" or an lvalue reference type" );
__uniq_ptr_impl() = default;
_GLIBCXX23_CONSTEXPR
__uniq_ptr_impl(pointer __p) : _M_t() { _M_ptr() = __p; }
template<typename _Del>
_GLIBCXX23_CONSTEXPR
__uniq_ptr_impl(pointer __p, _Del&& __d)
: _M_t(__p, std::forward<_Del>(__d)) { }
_GLIBCXX23_CONSTEXPR
__uniq_ptr_impl(__uniq_ptr_impl&& __u) noexcept
: _M_t(std::move(__u._M_t))
{ __u._M_ptr() = nullptr; }
_GLIBCXX23_CONSTEXPR
__uniq_ptr_impl& operator=(__uniq_ptr_impl&& __u) noexcept
{
reset(__u.release());
_M_deleter() = std::forward<_Dp>(__u._M_deleter());
return *this;
}
_GLIBCXX23_CONSTEXPR
pointer& _M_ptr() noexcept { return std::get<0>(_M_t); }
_GLIBCXX23_CONSTEXPR
pointer _M_ptr() const noexcept { return std::get<0>(_M_t); }
_GLIBCXX23_CONSTEXPR
_Dp& _M_deleter() noexcept { return std::get<1>(_M_t); }
_GLIBCXX23_CONSTEXPR
const _Dp& _M_deleter() const noexcept { return std::get<1>(_M_t); }
_GLIBCXX23_CONSTEXPR
void reset(pointer __p) noexcept
{
const pointer __old_p = _M_ptr();
_M_ptr() = __p;
if (__old_p)
_M_deleter()(__old_p);
}
_GLIBCXX23_CONSTEXPR
pointer release() noexcept
{
pointer __p = _M_ptr();
_M_ptr() = nullptr;
return __p;
}
_GLIBCXX23_CONSTEXPR
void
swap(__uniq_ptr_impl& __rhs) noexcept
{
using std::swap;
swap(this->_M_ptr(), __rhs._M_ptr());
swap(this->_M_deleter(), __rhs._M_deleter());
}
private:
tuple<pointer, _Dp> _M_t;
};
// Defines move construction + assignment as either defaulted or deleted.
template <typename _Tp, typename _Dp,
bool = is_move_constructible<_Dp>::value,
bool = is_move_assignable<_Dp>::value>
struct __uniq_ptr_data : __uniq_ptr_impl<_Tp, _Dp>
{
using __uniq_ptr_impl<_Tp, _Dp>::__uniq_ptr_impl;
__uniq_ptr_data(__uniq_ptr_data&&) = default;
__uniq_ptr_data& operator=(__uniq_ptr_data&&) = default;
};
template <typename _Tp, typename _Dp>
struct __uniq_ptr_data<_Tp, _Dp, true, false> : __uniq_ptr_impl<_Tp, _Dp>
{
using __uniq_ptr_impl<_Tp, _Dp>::__uniq_ptr_impl;
__uniq_ptr_data(__uniq_ptr_data&&) = default;
__uniq_ptr_data& operator=(__uniq_ptr_data&&) = delete;
};
template <typename _Tp, typename _Dp>
struct __uniq_ptr_data<_Tp, _Dp, false, true> : __uniq_ptr_impl<_Tp, _Dp>
{
using __uniq_ptr_impl<_Tp, _Dp>::__uniq_ptr_impl;
__uniq_ptr_data(__uniq_ptr_data&&) = delete;
__uniq_ptr_data& operator=(__uniq_ptr_data&&) = default;
};
template <typename _Tp, typename _Dp>
struct __uniq_ptr_data<_Tp, _Dp, false, false> : __uniq_ptr_impl<_Tp, _Dp>
{
using __uniq_ptr_impl<_Tp, _Dp>::__uniq_ptr_impl;
__uniq_ptr_data(__uniq_ptr_data&&) = delete;
__uniq_ptr_data& operator=(__uniq_ptr_data&&) = delete;
};
/// @endcond
// 20.7.1.2 unique_ptr for single objects.
/// A move-only smart pointer that manages unique ownership of a resource.
/// @headerfile memory
/// @since C++11
template <typename _Tp, typename _Dp = default_delete<_Tp>>
class unique_ptr
{
template <typename _Up>
using _DeleterConstraint =
typename __uniq_ptr_impl<_Tp, _Up>::_DeleterConstraint::type;
__uniq_ptr_data<_Tp, _Dp> _M_t;
public:
using pointer = typename __uniq_ptr_impl<_Tp, _Dp>::pointer;
using element_type = _Tp;
using deleter_type = _Dp;
private:
// helper template for detecting a safe conversion from another
// unique_ptr
template<typename _Up, typename _Ep>
using __safe_conversion_up = __and_<
is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>,
__not_<is_array<_Up>>
>;
#if ! __cpp_concepts
template<typename _Ptr, typename = void>
struct _Nothrow_deref
: false_type { };
template<typename _Ptr>
struct _Nothrow_deref<_Ptr, __void_t<decltype(*std::declval<_Ptr>())>>
: __bool_constant<noexcept(*std::declval<_Ptr>())> { };
#endif
public:
// Constructors.
/// Default constructor, creates a unique_ptr that owns nothing.
template<typename _Del = _Dp, typename = _DeleterConstraint<_Del>>
constexpr unique_ptr() noexcept
: _M_t()
{ }
/** Takes ownership of a pointer.
*
* @param __p A pointer to an object of @c element_type
*
* The deleter will be value-initialized.
*/
template<typename _Del = _Dp, typename = _DeleterConstraint<_Del>>
_GLIBCXX23_CONSTEXPR
explicit
unique_ptr(pointer __p) noexcept
: _M_t(__p)
{ }
/** Takes ownership of a pointer.
*
* @param __p A pointer to an object of @c element_type
* @param __d A reference to a deleter.
*
* The deleter will be initialized with @p __d
*/
template<typename _Del = deleter_type,
typename = _Require<is_copy_constructible<_Del>>>
_GLIBCXX23_CONSTEXPR
unique_ptr(pointer __p, const deleter_type& __d) noexcept
: _M_t(__p, __d) { }
/** Takes ownership of a pointer.
*
* @param __p A pointer to an object of @c element_type
* @param __d An rvalue reference to a (non-reference) deleter.
*
* The deleter will be initialized with @p std::move(__d)
*/
template<typename _Del = deleter_type,
typename = _Require<is_move_constructible<_Del>>>
_GLIBCXX23_CONSTEXPR
unique_ptr(pointer __p,
__enable_if_t<!is_lvalue_reference<_Del>::value,
_Del&&> __d) noexcept
: _M_t(__p, std::move(__d))
{ }
template<typename _Del = deleter_type,
typename _DelUnref = typename remove_reference<_Del>::type>
_GLIBCXX23_CONSTEXPR
unique_ptr(pointer,
__enable_if_t<is_lvalue_reference<_Del>::value,
_DelUnref&&>) = delete;
/// Creates a unique_ptr that owns nothing.
template<typename _Del = _Dp, typename = _DeleterConstraint<_Del>>
constexpr unique_ptr(nullptr_t) noexcept
: _M_t()
{ }
// Move constructors.
/// Move constructor.
unique_ptr(unique_ptr&&) = default;
/** @brief Converting constructor from another type
*
* Requires that the pointer owned by @p __u is convertible to the
* type of pointer owned by this object, @p __u does not own an array,
* and @p __u has a compatible deleter type.
*/
template<typename _Up, typename _Ep, typename = _Require<
__safe_conversion_up<_Up, _Ep>,
__conditional_t<is_reference<_Dp>::value,
is_same<_Ep, _Dp>,
is_convertible<_Ep, _Dp>>>>
_GLIBCXX23_CONSTEXPR
unique_ptr(unique_ptr<_Up, _Ep>&& __u) noexcept
: _M_t(__u.release(), std::forward<_Ep>(__u.get_deleter()))
{ }
#if _GLIBCXX_USE_DEPRECATED
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
/// Converting constructor from @c auto_ptr
template<typename _Up,
typename = _Require<is_convertible<_Up*, pointer>,
is_same<_Dp, default_delete<_Tp>>>>
unique_ptr(auto_ptr<_Up>&& __u) noexcept;
#pragma GCC diagnostic pop
#endif
/// Destructor, invokes the deleter if the stored pointer is not null.
#if __cplusplus > 202002L && __cpp_constexpr_dynamic_alloc
constexpr
#endif
~unique_ptr() noexcept
{
static_assert(__is_invocable<deleter_type&, pointer>::value,
"unique_ptr's deleter must be invocable with a pointer");
auto& __ptr = _M_t._M_ptr();
if (__ptr != nullptr)
get_deleter()(std::move(__ptr));
__ptr = pointer();
}
// Assignment.
/** @brief Move assignment operator.
*
* Invokes the deleter if this object owns a pointer.
*/
unique_ptr& operator=(unique_ptr&&) = default;
/** @brief Assignment from another type.
*
* @param __u The object to transfer ownership from, which owns a
* convertible pointer to a non-array object.
*
* Invokes the deleter if this object owns a pointer.
*/
template<typename _Up, typename _Ep>
_GLIBCXX23_CONSTEXPR
typename enable_if< __and_<
__safe_conversion_up<_Up, _Ep>,
is_assignable<deleter_type&, _Ep&&>
>::value,
unique_ptr&>::type
operator=(unique_ptr<_Up, _Ep>&& __u) noexcept
{
reset(__u.release());
get_deleter() = std::forward<_Ep>(__u.get_deleter());
return *this;
}
/// Reset the %unique_ptr to empty, invoking the deleter if necessary.
_GLIBCXX23_CONSTEXPR
unique_ptr&
operator=(nullptr_t) noexcept
{
reset();
return *this;
}
// Observers.
/// Dereference the stored pointer.
_GLIBCXX23_CONSTEXPR
typename add_lvalue_reference<element_type>::type
operator*() const
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 2762. unique_ptr operator*() should be noexcept
// 4324. unique_ptr<void>::operator* is not SFINAE-friendly
#if __cpp_concepts
noexcept(noexcept(*std::declval<pointer>()))
requires requires { *std::declval<pointer>(); }
#else
noexcept(_Nothrow_deref<pointer>::value)
#endif
{
#if _GLIBCXX_USE_BUILTIN_TRAIT(__reference_converts_from_temporary)
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 4148. unique_ptr::operator* should not allow dangling references
using _ResT = typename add_lvalue_reference<element_type>::type;
using _DerefT = decltype(*get());
static_assert(!__reference_converts_from_temporary(_ResT, _DerefT),
"operator* must not return a dangling reference");
#endif
__glibcxx_assert(get() != pointer());
return *get();
}
/// Return the stored pointer.
_GLIBCXX23_CONSTEXPR
pointer
operator->() const noexcept
{
_GLIBCXX_DEBUG_PEDASSERT(get() != pointer());
return get();
}
/// Return the stored pointer.
_GLIBCXX23_CONSTEXPR
pointer
get() const noexcept
{ return _M_t._M_ptr(); }
/// Return a reference to the stored deleter.
_GLIBCXX23_CONSTEXPR
deleter_type&
get_deleter() noexcept
{ return _M_t._M_deleter(); }
/// Return a reference to the stored deleter.
_GLIBCXX23_CONSTEXPR
const deleter_type&
get_deleter() const noexcept
{ return _M_t._M_deleter(); }
/// Return @c true if the stored pointer is not null.
_GLIBCXX23_CONSTEXPR
explicit operator bool() const noexcept
{ return get() == pointer() ? false : true; }
// Modifiers.
/// Release ownership of any stored pointer.
_GLIBCXX23_CONSTEXPR
pointer
release() noexcept
{ return _M_t.release(); }
/** @brief Replace the stored pointer.
*
* @param __p The new pointer to store.
*
* The deleter will be invoked if a pointer is already owned.
*/
_GLIBCXX23_CONSTEXPR
void
reset(pointer __p = pointer()) noexcept
{
static_assert(__is_invocable<deleter_type&, pointer>::value,
"unique_ptr's deleter must be invocable with a pointer");
_M_t.reset(std::move(__p));
}
/// Exchange the pointer and deleter with another object.
_GLIBCXX23_CONSTEXPR
void
swap(unique_ptr& __u) noexcept
{
static_assert(__is_swappable<_Dp>::value, "deleter must be swappable");
_M_t.swap(__u._M_t);
}
// Disable copy from lvalue.
unique_ptr(const unique_ptr&) = delete;
unique_ptr& operator=(const unique_ptr&) = delete;
private:
#ifdef __glibcxx_out_ptr
template<typename, typename, typename...>
friend class out_ptr_t;
template<typename, typename, typename...>
friend class inout_ptr_t;
#endif
};
// 20.7.1.3 unique_ptr for array objects with a runtime length
// [unique.ptr.runtime]
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// DR 740 - omit specialization for array objects with a compile time length
/// A move-only smart pointer that manages unique ownership of an array.
/// @headerfile memory
/// @since C++11
template<typename _Tp, typename _Dp>
class unique_ptr<_Tp[], _Dp>
{
template <typename _Up>
using _DeleterConstraint =
typename __uniq_ptr_impl<_Tp, _Up>::_DeleterConstraint::type;
__uniq_ptr_data<_Tp, _Dp> _M_t;
// like is_base_of<_Tp, _Up> but false if unqualified types are the same
template<typename _Up>
using __is_derived_Tp
= __and_< is_base_of<_Tp, _Up>,
__not_<is_same<__remove_cv_t<_Tp>, __remove_cv_t<_Up>>> >;
public:
using pointer = typename __uniq_ptr_impl<_Tp, _Dp>::pointer;
using element_type = _Tp;
using deleter_type = _Dp;
// helper template for detecting a safe conversion from another
// unique_ptr
template<typename _Up, typename _Ep,
typename _UPtr = unique_ptr<_Up, _Ep>,
typename _UP_pointer = typename _UPtr::pointer,
typename _UP_element_type = typename _UPtr::element_type>
using __safe_conversion_up = __and_<
is_array<_Up>,
is_same<pointer, element_type*>,
is_same<_UP_pointer, _UP_element_type*>,
is_convertible<_UP_element_type(*)[], element_type(*)[]>
>;
// helper template for detecting a safe conversion from a raw pointer
template<typename _Up>
using __safe_conversion_raw = __and_<
__or_<__or_<is_same<_Up, pointer>,
is_same<_Up, nullptr_t>>,
__and_<is_pointer<_Up>,
is_same<pointer, element_type*>,
is_convertible<
typename remove_pointer<_Up>::type(*)[],
element_type(*)[]>
>
>
>;
// Constructors.
/// Default constructor, creates a unique_ptr that owns nothing.
template<typename _Del = _Dp, typename = _DeleterConstraint<_Del>>
constexpr unique_ptr() noexcept
: _M_t()
{ }
/** Takes ownership of a pointer.
*
* @param __p A pointer to an array of a type safely convertible
* to an array of @c element_type
*
* The deleter will be value-initialized.
*/
template<typename _Up,
typename _Vp = _Dp,
typename = _DeleterConstraint<_Vp>,
typename = typename enable_if<
__safe_conversion_raw<_Up>::value, bool>::type>
_GLIBCXX23_CONSTEXPR
explicit
unique_ptr(_Up __p) noexcept
: _M_t(__p)
{ }
/** Takes ownership of a pointer.
*
* @param __p A pointer to an array of a type safely convertible
* to an array of @c element_type
* @param __d A reference to a deleter.
*
* The deleter will be initialized with @p __d
*/
template<typename _Up, typename _Del = deleter_type,
typename = _Require<__safe_conversion_raw<_Up>,
is_copy_constructible<_Del>>>
_GLIBCXX23_CONSTEXPR
unique_ptr(_Up __p, const deleter_type& __d) noexcept
: _M_t(__p, __d) { }
/** Takes ownership of a pointer.
*
* @param __p A pointer to an array of a type safely convertible
* to an array of @c element_type
* @param __d A reference to a deleter.
*
* The deleter will be initialized with @p std::move(__d)
*/
template<typename _Up, typename _Del = deleter_type,
typename = _Require<__safe_conversion_raw<_Up>,
is_move_constructible<_Del>>>
_GLIBCXX23_CONSTEXPR
unique_ptr(_Up __p,
__enable_if_t<!is_lvalue_reference<_Del>::value,
_Del&&> __d) noexcept
: _M_t(std::move(__p), std::move(__d))
{ }
template<typename _Up, typename _Del = deleter_type,
typename _DelUnref = typename remove_reference<_Del>::type,
typename = _Require<__safe_conversion_raw<_Up>>>
unique_ptr(_Up,
__enable_if_t<is_lvalue_reference<_Del>::value,
_DelUnref&&>) = delete;
/// Move constructor.
unique_ptr(unique_ptr&&) = default;
/// Creates a unique_ptr that owns nothing.
template<typename _Del = _Dp, typename = _DeleterConstraint<_Del>>
constexpr unique_ptr(nullptr_t) noexcept
: _M_t()
{ }
template<typename _Up, typename _Ep, typename = _Require<
__safe_conversion_up<_Up, _Ep>,
__conditional_t<is_reference<_Dp>::value,
is_same<_Ep, _Dp>,
is_convertible<_Ep, _Dp>>>>
_GLIBCXX23_CONSTEXPR
unique_ptr(unique_ptr<_Up, _Ep>&& __u) noexcept
: _M_t(__u.release(), std::forward<_Ep>(__u.get_deleter()))
{ }
/// Destructor, invokes the deleter if the stored pointer is not null.
#if __cplusplus > 202002L && __cpp_constexpr_dynamic_alloc
constexpr
#endif
~unique_ptr()
{
auto& __ptr = _M_t._M_ptr();
if (__ptr != nullptr)
get_deleter()(__ptr);
__ptr = pointer();
}
// Assignment.
/** @brief Move assignment operator.
*
* Invokes the deleter if this object owns a pointer.
*/
unique_ptr&
operator=(unique_ptr&&) = default;
/** @brief Assignment from another type.
*
* @param __u The object to transfer ownership from, which owns a
* convertible pointer to an array object.
*
* Invokes the deleter if this object owns a pointer.
*/
template<typename _Up, typename _Ep>
_GLIBCXX23_CONSTEXPR
typename
enable_if<__and_<__safe_conversion_up<_Up, _Ep>,
is_assignable<deleter_type&, _Ep&&>
>::value,
unique_ptr&>::type
operator=(unique_ptr<_Up, _Ep>&& __u) noexcept
{
reset(__u.release());
get_deleter() = std::forward<_Ep>(__u.get_deleter());
return *this;
}
/// Reset the %unique_ptr to empty, invoking the deleter if necessary.
_GLIBCXX23_CONSTEXPR
unique_ptr&
operator=(nullptr_t) noexcept
{
reset();
return *this;
}
// Observers.
/// Access an element of owned array.
_GLIBCXX23_CONSTEXPR
typename std::add_lvalue_reference<element_type>::type
operator[](size_t __i) const
{
__glibcxx_assert(get() != pointer());
return get()[__i];
}
/// Return the stored pointer.
_GLIBCXX23_CONSTEXPR
pointer
get() const noexcept
{ return _M_t._M_ptr(); }
/// Return a reference to the stored deleter.
_GLIBCXX23_CONSTEXPR
deleter_type&
get_deleter() noexcept
{ return _M_t._M_deleter(); }
/// Return a reference to the stored deleter.
_GLIBCXX23_CONSTEXPR
const deleter_type&
get_deleter() const noexcept
{ return _M_t._M_deleter(); }
/// Return @c true if the stored pointer is not null.
_GLIBCXX23_CONSTEXPR
explicit operator bool() const noexcept
{ return get() == pointer() ? false : true; }
// Modifiers.
/// Release ownership of any stored pointer.
_GLIBCXX23_CONSTEXPR
pointer
release() noexcept
{ return _M_t.release(); }
/** @brief Replace the stored pointer.
*
* @param __p The new pointer to store.
*
* The deleter will be invoked if a pointer is already owned.
*/
template <typename _Up,
typename = _Require<
__or_<is_same<_Up, pointer>,
__and_<is_same<pointer, element_type*>,
is_pointer<_Up>,
is_convertible<
typename remove_pointer<_Up>::type(*)[],
element_type(*)[]
>
>
>
>>
_GLIBCXX23_CONSTEXPR
void
reset(_Up __p) noexcept
{ _M_t.reset(std::move(__p)); }
_GLIBCXX23_CONSTEXPR
void reset(nullptr_t = nullptr) noexcept
{ reset(pointer()); }
/// Exchange the pointer and deleter with another object.
_GLIBCXX23_CONSTEXPR
void
swap(unique_ptr& __u) noexcept
{
static_assert(__is_swappable<_Dp>::value, "deleter must be swappable");
_M_t.swap(__u._M_t);
}
// Disable copy from lvalue.
unique_ptr(const unique_ptr&) = delete;
unique_ptr& operator=(const unique_ptr&) = delete;
private:
#ifdef __glibcxx_out_ptr
template<typename, typename, typename...> friend class out_ptr_t;
template<typename, typename, typename...> friend class inout_ptr_t;
#endif
};
/// @{
/// @relates unique_ptr
/// Swap overload for unique_ptr
template<typename _Tp, typename _Dp>
inline
#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
// Constrained free swap overload, see p0185r1
_GLIBCXX23_CONSTEXPR
typename enable_if<__is_swappable<_Dp>::value>::type
#else
void
#endif
swap(unique_ptr<_Tp, _Dp>& __x,
unique_ptr<_Tp, _Dp>& __y) noexcept
{ __x.swap(__y); }
#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
template<typename _Tp, typename _Dp>
typename enable_if<!__is_swappable<_Dp>::value>::type
swap(unique_ptr<_Tp, _Dp>&,
unique_ptr<_Tp, _Dp>&) = delete;
#endif
/// Equality operator for unique_ptr objects, compares the owned pointers
template<typename _Tp, typename _Dp,
typename _Up, typename _Ep>
_GLIBCXX_NODISCARD _GLIBCXX23_CONSTEXPR
inline bool
operator==(const unique_ptr<_Tp, _Dp>& __x,
const unique_ptr<_Up, _Ep>& __y)
{ return __x.get() == __y.get(); }
/// unique_ptr comparison with nullptr
template<typename _Tp, typename _Dp>
_GLIBCXX_NODISCARD _GLIBCXX23_CONSTEXPR
inline bool
operator==(const unique_ptr<_Tp, _Dp>& __x, nullptr_t) noexcept
{ return !__x; }
#ifndef __cpp_lib_three_way_comparison
/// unique_ptr comparison with nullptr
template<typename _Tp, typename _Dp>
_GLIBCXX_NODISCARD
inline bool
operator==(nullptr_t, const unique_ptr<_Tp, _Dp>& __x) noexcept
{ return !__x; }
/// Inequality operator for unique_ptr objects, compares the owned pointers
template<typename _Tp, typename _Dp,
typename _Up, typename _Ep>
_GLIBCXX_NODISCARD
inline bool
operator!=(const unique_ptr<_Tp, _Dp>& __x,
const unique_ptr<_Up, _Ep>& __y)
{ return __x.get() != __y.get(); }
/// unique_ptr comparison with nullptr
template<typename _Tp, typename _Dp>
_GLIBCXX_NODISCARD
inline bool
operator!=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t) noexcept
{ return (bool)__x; }
/// unique_ptr comparison with nullptr
template<typename _Tp, typename _Dp>
_GLIBCXX_NODISCARD
inline bool
operator!=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x) noexcept
{ return (bool)__x; }
#endif // three way comparison
/// Relational operator for unique_ptr objects, compares the owned pointers
template<typename _Tp, typename _Dp,
typename _Up, typename _Ep>
_GLIBCXX_NODISCARD _GLIBCXX23_CONSTEXPR
inline bool
operator<(const unique_ptr<_Tp, _Dp>& __x,
const unique_ptr<_Up, _Ep>& __y)
{
typedef typename
std::common_type<typename unique_ptr<_Tp, _Dp>::pointer,
typename unique_ptr<_Up, _Ep>::pointer>::type _CT;
return std::less<_CT>()(__x.get(), __y.get());
}
/// unique_ptr comparison with nullptr
template<typename _Tp, typename _Dp>
_GLIBCXX_NODISCARD _GLIBCXX23_CONSTEXPR
inline bool
operator<(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
{
return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(__x.get(),
nullptr);
}
/// unique_ptr comparison with nullptr
template<typename _Tp, typename _Dp>
_GLIBCXX_NODISCARD _GLIBCXX23_CONSTEXPR
inline bool
operator<(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
{
return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(nullptr,
__x.get());
}
/// Relational operator for unique_ptr objects, compares the owned pointers
template<typename _Tp, typename _Dp,
typename _Up, typename _Ep>
_GLIBCXX_NODISCARD _GLIBCXX23_CONSTEXPR
inline bool
operator<=(const unique_ptr<_Tp, _Dp>& __x,
const unique_ptr<_Up, _Ep>& __y)
{ return !(__y < __x); }
/// unique_ptr comparison with nullptr
template<typename _Tp, typename _Dp>
_GLIBCXX_NODISCARD _GLIBCXX23_CONSTEXPR
inline bool
operator<=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
{ return !(nullptr < __x); }
/// unique_ptr comparison with nullptr
template<typename _Tp, typename _Dp>
_GLIBCXX_NODISCARD _GLIBCXX23_CONSTEXPR
inline bool
operator<=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
{ return !(__x < nullptr); }
/// Relational operator for unique_ptr objects, compares the owned pointers
template<typename _Tp, typename _Dp,
typename _Up, typename _Ep>
_GLIBCXX_NODISCARD _GLIBCXX23_CONSTEXPR
inline bool
operator>(const unique_ptr<_Tp, _Dp>& __x,
const unique_ptr<_Up, _Ep>& __y)
{ return (__y < __x); }
/// unique_ptr comparison with nullptr
template<typename _Tp, typename _Dp>
_GLIBCXX_NODISCARD _GLIBCXX23_CONSTEXPR
inline bool
operator>(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
{
return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(nullptr,
__x.get());
}
/// unique_ptr comparison with nullptr
template<typename _Tp, typename _Dp>
_GLIBCXX_NODISCARD _GLIBCXX23_CONSTEXPR
inline bool
operator>(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
{
return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(__x.get(),
nullptr);
}
/// Relational operator for unique_ptr objects, compares the owned pointers
template<typename _Tp, typename _Dp,
typename _Up, typename _Ep>
_GLIBCXX_NODISCARD _GLIBCXX23_CONSTEXPR
inline bool
operator>=(const unique_ptr<_Tp, _Dp>& __x,
const unique_ptr<_Up, _Ep>& __y)
{ return !(__x < __y); }
/// unique_ptr comparison with nullptr
template<typename _Tp, typename _Dp>
_GLIBCXX_NODISCARD _GLIBCXX23_CONSTEXPR
inline bool
operator>=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
{ return !(__x < nullptr); }
/// unique_ptr comparison with nullptr
template<typename _Tp, typename _Dp>
_GLIBCXX_NODISCARD inline bool
operator>=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
{ return !(nullptr < __x); }
#ifdef __cpp_lib_three_way_comparison
template<typename _Tp, typename _Dp, typename _Up, typename _Ep>
requires three_way_comparable_with<typename unique_ptr<_Tp, _Dp>::pointer,
typename unique_ptr<_Up, _Ep>::pointer>
_GLIBCXX23_CONSTEXPR
inline
compare_three_way_result_t<typename unique_ptr<_Tp, _Dp>::pointer,
typename unique_ptr<_Up, _Ep>::pointer>
operator<=>(const unique_ptr<_Tp, _Dp>& __x,
const unique_ptr<_Up, _Ep>& __y)
{ return compare_three_way()(__x.get(), __y.get()); }
template<typename _Tp, typename _Dp>
requires three_way_comparable<typename unique_ptr<_Tp, _Dp>::pointer>
_GLIBCXX23_CONSTEXPR
inline
compare_three_way_result_t<typename unique_ptr<_Tp, _Dp>::pointer>
operator<=>(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
{
using pointer = typename unique_ptr<_Tp, _Dp>::pointer;
return compare_three_way()(__x.get(), static_cast<pointer>(nullptr));
}
#endif
/// @} relates unique_ptr
/// @cond undocumented
template<typename _Up, typename _Ptr = typename _Up::pointer>
struct __uniq_ptr_hash
: public __hash_base<size_t, _Up>
#if ! _GLIBCXX_INLINE_VERSION
, private __hash_empty_base<_Ptr>
#endif
{
size_t
operator()(const _Up& __u) const
noexcept(noexcept(std::declval<hash<_Ptr>>()(std::declval<_Ptr>())))
{ return hash<_Ptr>()(__u.get()); }
};
template<typename _Up>
using __uniq_ptr_hash_base
= __conditional_t<__is_hash_enabled_for<typename _Up::pointer>,
__uniq_ptr_hash<_Up>,
__hash_not_enabled<typename _Up::pointer>>;
/// @endcond
/// std::hash specialization for unique_ptr.
template<typename _Tp, typename _Dp>
struct hash<unique_ptr<_Tp, _Dp>>
: public __uniq_ptr_hash_base<unique_ptr<_Tp, _Dp>>
{ };
#ifdef __glibcxx_make_unique // C++ >= 14 && HOSTED
/// @cond undocumented
namespace __detail
{
template<typename _Tp>
struct _MakeUniq
{ typedef unique_ptr<_Tp> __single_object; };
template<typename _Tp>
struct _MakeUniq<_Tp[]>
{ typedef unique_ptr<_Tp[]> __array; };
template<typename _Tp, size_t _Bound>
struct _MakeUniq<_Tp[_Bound]>
{ struct __invalid_type { }; };
template<typename _Tp>
using __unique_ptr_t = typename _MakeUniq<_Tp>::__single_object;
template<typename _Tp>
using __unique_ptr_array_t = typename _MakeUniq<_Tp>::__array;
template<typename _Tp>
using __invalid_make_unique_t = typename _MakeUniq<_Tp>::__invalid_type;
}
/// @endcond
/** Create an object owned by a `unique_ptr`.
* @tparam _Tp A non-array object type.
* @param __args Constructor arguments for the new object.
* @returns A `unique_ptr<_Tp>` that owns the new object.
* @since C++14
* @relates unique_ptr
*/
template<typename _Tp, typename... _Args>
_GLIBCXX23_CONSTEXPR
inline __detail::__unique_ptr_t<_Tp>
make_unique(_Args&&... __args)
{ return unique_ptr<_Tp>(new _Tp(std::forward<_Args>(__args)...)); }
/** Create an array owned by a `unique_ptr`.
* @tparam _Tp An array type of unknown bound, such as `U[]`.
* @param __num The number of elements of type `U` in the new array.
* @returns A `unique_ptr<U[]>` that owns the new array.
* @since C++14
* @relates unique_ptr
*
* The array elements are value-initialized.
*/
template<typename _Tp>
_GLIBCXX23_CONSTEXPR
inline __detail::__unique_ptr_array_t<_Tp>
make_unique(size_t __num)
{ return unique_ptr<_Tp>(new remove_extent_t<_Tp>[__num]()); }
/** Disable std::make_unique for arrays of known bound.
* @tparam _Tp An array type of known bound, such as `U[N]`.
* @since C++14
* @relates unique_ptr
*/
template<typename _Tp, typename... _Args>
__detail::__invalid_make_unique_t<_Tp>
make_unique(_Args&&...) = delete;
#if __cplusplus > 201703L
/** Create a default-initialied object owned by a `unique_ptr`.
* @tparam _Tp A non-array object type.
* @returns A `unique_ptr<_Tp>` that owns the new object.
* @since C++20
* @relates unique_ptr
*/
template<typename _Tp>
_GLIBCXX23_CONSTEXPR
inline __detail::__unique_ptr_t<_Tp>
make_unique_for_overwrite()
{ return unique_ptr<_Tp>(new _Tp); }
/** Create a default-initialized array owned by a `unique_ptr`.
* @tparam _Tp An array type of unknown bound, such as `U[]`.
* @param __num The number of elements of type `U` in the new array.
* @returns A `unique_ptr<U[]>` that owns the new array.
* @since C++20
* @relates unique_ptr
*/
template<typename _Tp>
_GLIBCXX23_CONSTEXPR
inline __detail::__unique_ptr_array_t<_Tp>
make_unique_for_overwrite(size_t __num)
{ return unique_ptr<_Tp>(new remove_extent_t<_Tp>[__num]); }
/** Disable std::make_unique_for_overwrite for arrays of known bound.
* @tparam _Tp An array type of known bound, such as `U[N]`.
* @since C++20
* @relates unique_ptr
*/
template<typename _Tp, typename... _Args>
__detail::__invalid_make_unique_t<_Tp>
make_unique_for_overwrite(_Args&&...) = delete;
#endif // C++20
#endif // C++14 && HOSTED
#if __cplusplus > 201703L && __cpp_concepts && _GLIBCXX_HOSTED
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 2948. unique_ptr does not define operator<< for stream output
/// Stream output operator for unique_ptr
/// @relates unique_ptr
/// @since C++20
template<typename _CharT, typename _Traits, typename _Tp, typename _Dp>
inline basic_ostream<_CharT, _Traits>&
operator<<(basic_ostream<_CharT, _Traits>& __os,
const unique_ptr<_Tp, _Dp>& __p)
requires requires { __os << __p.get(); }
{
__os << __p.get();
return __os;
}
#endif // C++20 && HOSTED
#if __cpp_variable_templates
template<typename _Tp>
constexpr bool __is_unique_ptr = false;
template<typename _Tp, typename _Del>
constexpr bool __is_unique_ptr<unique_ptr<_Tp, _Del>> = true;
#endif
/// @} group pointer_abstractions
#if __cplusplus >= 201703L
namespace __detail::__variant
{
template<typename> struct _Never_valueless_alt; // see <variant>
// Provide the strong exception-safety guarantee when emplacing a
// unique_ptr into a variant.
template<typename _Tp, typename _Del>
struct _Never_valueless_alt<std::unique_ptr<_Tp, _Del>>
: std::true_type
{ };
} // namespace __detail::__variant
#endif // C++17
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
#endif /* _UNIQUE_PTR_H */
compare
tuple
type_traits
ostream.h
stl_function.h
functional_hash.h
c++config.h
assertions.h
std::unique_ptr::swap
constexpr enable_if< __is_swappable< _Dp >::value >::type swap(unique_ptr< _Tp, _Dp > &__x, unique_ptr< _Tp, _Dp > &__y) noexcept
Swap overload for unique_ptr.
Definition unique_ptr.h:848
std::true_type
__bool_constant< true > true_type
The type used as a compile-time boolean with true value.
Definition type_traits:117
std::remove_extent_t
typename remove_extent< _Tp >::type remove_extent_t
Alias template for remove_extent.
Definition type_traits:2188
std::false_type
__bool_constant< false > false_type
The type used as a compile-time boolean with false value.
Definition type_traits:120
std::declval
auto declval() noexcept -> decltype(__declval< _Tp >(0))
Definition type_traits:2610
std::move
constexpr std::remove_reference< _Tp >::type && move(_Tp &&__t) noexcept
Convert a value to an rvalue.
Definition move.h:138
std::forward
constexpr _Tp && forward(typename std::remove_reference< _Tp >::type &__t) noexcept
Forward an lvalue.
Definition move.h:72
std
ISO C++ entities toplevel namespace is std.
std::compare_three_way_result_t
typename __detail::__cmp3way_res_impl< _Tp, _Up >::type compare_three_way_result_t
[cmp.result], result of three-way comparison
Definition compare:524
std::operator<<
std::basic_ostream< _CharT, _Traits > & operator<<(std::basic_ostream< _CharT, _Traits > &__os, const bitset< _Nb > &__x)
Global I/O operators for bitsets.
Definition bitset:1692
std::basic_ostream
Template class basic_ostream.
Definition ostream.h:67
std::hash
Primary class template hash.
Definition functional_hash.h:106
std::enable_if
Define a member typedef type only if a boolean constant is true.
Definition type_traits:135
std::is_void
is_void
Definition type_traits:324
std::is_array
is_array
Definition type_traits:535
std::is_pointer
is_pointer
Definition type_traits:555
std::is_lvalue_reference
is_lvalue_reference
Definition type_traits:581
std::is_same
is_same
Definition type_traits:1535
std::is_copy_constructible
is_copy_constructible
Definition type_traits:1194
std::is_move_constructible
is_move_constructible
Definition type_traits:1221
std::is_assignable
is_assignable
Definition type_traits:1277
std::is_move_assignable
is_move_assignable
Definition type_traits:1296
std::type
std::common_type
common_type
Definition type_traits:2469
std::auto_ptr
A simple smart pointer providing strict ownership semantics.
Definition auto_ptr.h:94
std::less
One of the comparison functors.
Definition stl_function.h:404
std::default_delete::operator()
constexpr void operator()(_Tp *__ptr) const
Calls delete __ptr.
Definition unique_ptr.h:86
std::default_delete::default_delete
constexpr default_delete() noexcept=default
Default constructor.
std::default_delete< _Tp[]>::operator()
constexpr enable_if< is_convertible< _Up(*)[], _Tp(*)[]>::value >::type operator()(_Up *__ptr) const
Calls delete[] __ptr.
Definition unique_ptr.h:129
std::default_delete< _Tp[]>::default_delete
constexpr default_delete() noexcept=default
Default constructor.
std::unique_ptr
A move-only smart pointer that manages unique ownership of a resource.
Definition unique_ptr.h:271
std::unique_ptr::operator->
constexpr pointer operator->() const noexcept
Return the stored pointer.
Definition unique_ptr.h:481
std::unique_ptr::operator*
constexpr add_lvalue_reference< element_type >::type operator*() const noexcept(noexcept(*std::declval< pointer >()))
Dereference the stored pointer.
Definition unique_ptr.h:455
std::unique_ptr::operator=
constexpr unique_ptr & operator=(nullptr_t) noexcept
Reset the unique_ptr to empty, invoking the deleter if necessary.
Definition unique_ptr.h:444
std::unique_ptr::unique_ptr
constexpr unique_ptr(pointer __p) noexcept
Definition unique_ptr.h:320
std::unique_ptr::unique_ptr
constexpr unique_ptr() noexcept
Default constructor, creates a unique_ptr that owns nothing.
Definition unique_ptr.h:307
std::unique_ptr::unique_ptr
constexpr unique_ptr(pointer __p, const deleter_type &__d) noexcept
Definition unique_ptr.h:334
std::unique_ptr::unique_ptr
unique_ptr(unique_ptr &&)=default
Move constructor.
std::unique_ptr::operator=
unique_ptr & operator=(unique_ptr &&)=default
Move assignment operator.
std::unique_ptr::reset
constexpr void reset(pointer __p=pointer()) noexcept
Replace the stored pointer.
Definition unique_ptr.h:526
std::unique_ptr::operator=
constexpr enable_if< __and_< __safe_conversion_up< _Up, _Ep >, is_assignable< deleter_type &, _Ep && > >::value, unique_ptr & >::type operator=(unique_ptr< _Up, _Ep > &&__u) noexcept
Assignment from another type.
Definition unique_ptr.h:434
std::unique_ptr::~unique_ptr
~unique_ptr() noexcept
Destructor, invokes the deleter if the stored pointer is not null.
Definition unique_ptr.h:402
std::unique_ptr::unique_ptr
unique_ptr(auto_ptr< _Up > &&__u) noexcept
Converting constructor from auto_ptr.
Definition auto_ptr.h:334
std::unique_ptr::unique_ptr
constexpr unique_ptr(unique_ptr< _Up, _Ep > &&__u) noexcept
Converting constructor from another type.
Definition unique_ptr.h:383
std::unique_ptr::get_deleter
constexpr deleter_type & get_deleter() noexcept
Return a reference to the stored deleter.
Definition unique_ptr.h:496
std::unique_ptr::swap
constexpr void swap(unique_ptr &__u) noexcept
Exchange the pointer and deleter with another object.
Definition unique_ptr.h:536
std::unique_ptr::get
constexpr pointer get() const noexcept
Return the stored pointer.
Definition unique_ptr.h:490
std::unique_ptr::unique_ptr
constexpr unique_ptr(pointer __p, __enable_if_t<!is_lvalue_reference< _Del >::value, _Del && > __d) noexcept
Definition unique_ptr.h:347
std::unique_ptr::release
constexpr pointer release() noexcept
Release ownership of any stored pointer.
Definition unique_ptr.h:515
std::unique_ptr::unique_ptr
constexpr unique_ptr(nullptr_t) noexcept
Creates a unique_ptr that owns nothing.
Definition unique_ptr.h:362
std::unique_ptr::get_deleter
constexpr const deleter_type & get_deleter() const noexcept
Return a reference to the stored deleter.
Definition unique_ptr.h:502
std::unique_ptr< _Tp[], _Dp >::get_deleter
constexpr deleter_type & get_deleter() noexcept
Return a reference to the stored deleter.
Definition unique_ptr.h:765
std::unique_ptr< _Tp[], _Dp >::release
constexpr pointer release() noexcept
Release ownership of any stored pointer.
Definition unique_ptr.h:784
std::unique_ptr< _Tp[], _Dp >::swap
constexpr void swap(unique_ptr &__u) noexcept
Exchange the pointer and deleter with another object.
Definition unique_ptr.h:817
std::unique_ptr< _Tp[], _Dp >::unique_ptr
constexpr unique_ptr() noexcept
Default constructor, creates a unique_ptr that owns nothing.
Definition unique_ptr.h:613
std::unique_ptr< _Tp[], _Dp >::reset
constexpr void reset(_Up __p) noexcept
Replace the stored pointer.
Definition unique_ptr.h:807
std::unique_ptr< _Tp[], _Dp >::get
constexpr pointer get() const noexcept
Return the stored pointer.
Definition unique_ptr.h:759
std::unique_ptr< _Tp[], _Dp >::operator=
unique_ptr & operator=(unique_ptr &&)=default
Move assignment operator.
std::unique_ptr< _Tp[], _Dp >::operator[]
constexpr std::add_lvalue_reference< element_type >::type operator[](size_t __i) const
Access an element of owned array.
Definition unique_ptr.h:750