1 // Guarded Allocation -*- C++ -*-
3 // Copyright (C) 2014-2018 Free Software Foundation, Inc.
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
25 /** @file bits/allocated_ptr.h
26 * This is an internal header file, included by other library headers.
27 * Do not attempt to use it directly. @headername{memory}
30 #ifndef _ALLOCATED_PTR_H
31 #define _ALLOCATED_PTR_H 1
33 #if __cplusplus < 201103L
34 # include <bits/c++0xwarning.h>
36 # include <type_traits>
37 # include <bits/ptr_traits.h>
38 # include <bits/alloc_traits.h>
40 namespace std
_GLIBCXX_VISIBILITY(default)
42 _GLIBCXX_BEGIN_NAMESPACE_VERSION
44 /// Non-standard RAII type for managing pointers obtained from allocators.
45 template<typename _Alloc
>
46 struct __allocated_ptr
48 using pointer
= typename allocator_traits
<_Alloc
>::pointer
;
49 using value_type
= typename allocator_traits
<_Alloc
>::value_type
;
51 /// Take ownership of __ptr
52 __allocated_ptr(_Alloc
& __a
, pointer __ptr
) noexcept
53 : _M_alloc(std::__addressof(__a
)), _M_ptr(__ptr
)
56 /// Convert __ptr to allocator's pointer type and take ownership of it
57 template<typename _Ptr
,
58 typename _Req
= _Require
<is_same
<_Ptr
, value_type
*>>>
59 __allocated_ptr(_Alloc
& __a
, _Ptr __ptr
)
60 : _M_alloc(std::__addressof(__a
)),
61 _M_ptr(pointer_traits
<pointer
>::pointer_to(*__ptr
))
64 /// Transfer ownership of the owned pointer
65 __allocated_ptr(__allocated_ptr
&& __gd
) noexcept
66 : _M_alloc(__gd
._M_alloc
), _M_ptr(__gd
._M_ptr
)
67 { __gd
._M_ptr
= nullptr; }
69 /// Deallocate the owned pointer
72 if (_M_ptr
!= nullptr)
73 std::allocator_traits
<_Alloc
>::deallocate(*_M_alloc
, _M_ptr
, 1);
76 /// Release ownership of the owned pointer
78 operator=(std::nullptr_t
) noexcept
84 /// Get the address that the owned pointer refers to.
85 value_type
* get() { return std::__to_address(_M_ptr
); }
92 /// Allocate space for a single object using __a
93 template<typename _Alloc
>
94 __allocated_ptr
<_Alloc
>
95 __allocate_guarded(_Alloc
& __a
)
97 return { __a
, std::allocator_traits
<_Alloc
>::allocate(__a
, 1) };
100 _GLIBCXX_END_NAMESPACE_VERSION