1// <memory> -*- C++ -*-
2
3// Copyright (C) 2001-2015 Free Software Foundation, Inc.
4//
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)
9// any later version.
10
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.
15
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.
19
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/>.
24
25/*
26 * Copyright (c) 1997-1999
27 * Silicon Graphics Computer Systems, Inc.
28 *
29 * Permission to use, copy, modify, distribute and sell this software
30 * and its documentation for any purpose is hereby granted without fee,
31 * provided that the above copyright notice appear in all copies and
32 * that both that copyright notice and this permission notice appear
33 * in supporting documentation.  Silicon Graphics makes no
34 * representations about the suitability of this software for any
35 * purpose.  It is provided "as is" without express or implied warranty.
36 *
37 */
38
39/** @file include/memory
40 *  This is a Standard C++ Library header.
41 */
42
43#ifndef _GLIBCXX_MEMORY
44#define _GLIBCXX_MEMORY 1
45
46#pragma GCC system_header
47
48/**
49 * @defgroup memory Memory
50 * @ingroup utilities
51 *
52 * Components for memory allocation, deallocation, and management.
53 */
54
55/**
56 * @defgroup pointer_abstractions Pointer Abstractions
57 * @ingroup memory
58 *
59 * Smart pointers, etc.
60 */
61
62#include <bits/stl_algobase.h>
63#include <bits/allocator.h>
64#include <bits/stl_construct.h>
65#include <bits/stl_uninitialized.h>
66#include <bits/stl_tempbuf.h>
67#include <bits/stl_raw_storage_iter.h>
68
69#if __cplusplus >= 201103L
70#  include <exception>        	  // std::exception
71#  include <typeinfo>         	  // std::type_info in get_deleter
72#  include <iosfwd>           	  // std::basic_ostream
73#  include <ext/atomicity.h>
74#  include <ext/concurrence.h>
75#  include <bits/functexcept.h>
76#  include <bits/stl_function.h>  // std::less
77#  include <bits/uses_allocator.h>
78#  include <type_traits>
79#  include <functional>
80#  include <debug/debug.h>
81#  include <bits/unique_ptr.h>
82#  include <bits/shared_ptr.h>
83#  include <bits/shared_ptr_atomic.h>
84#  if _GLIBCXX_USE_DEPRECATED
85#    include <backward/auto_ptr.h>
86#  endif
87#else
88#  include <backward/auto_ptr.h>
89#endif
90
91#if __cplusplus >= 201103L
92#  include <cstdint>
93#  ifdef _GLIBCXX_USE_C99_STDINT_TR1
94namespace std _GLIBCXX_VISIBILITY(default)
95{
96_GLIBCXX_BEGIN_NAMESPACE_VERSION
97
98/**
99 *  @brief Fit aligned storage in buffer.
100 *
101 *  [ptr.align]
102 *
103 *  This function tries to fit @a __size bytes of storage with alignment
104 *  @a __align into the buffer @a __ptr of size @a __space bytes.  If such
105 *  a buffer fits then @a __ptr is changed to point to the first byte of the
106 *  aligned storage and @a __space is reduced by the bytes used for alignment.
107 *
108 *  @param __align   A fundamental or extended alignment value.
109 *  @param __size    Size of the aligned storage required.
110 *  @param __ptr     Pointer to a buffer of @a __space bytes.
111 *  @param __space   Size of the buffer pointed to by @a __ptr.
112 *  @return the updated pointer if the aligned storage fits, otherwise nullptr.
113 */
114inline void*
115align(size_t __align, size_t __size, void*& __ptr, size_t& __space) noexcept
116{
117  const auto __intptr = reinterpret_cast<uintptr_t>(__ptr);
118  const auto __aligned = (__intptr - 1u + __align) & -__align;
119  const auto __diff = __aligned - __intptr;
120  if ((__size + __diff) > __space)
121    return nullptr;
122  else
123    {
124      __space -= __diff;
125      return __ptr = reinterpret_cast<void*>(__aligned);
126    }
127}
128
129_GLIBCXX_END_NAMESPACE_VERSION
130} // namespace
131#endif // _GLIBCXX_USE_C99_STDINT_TR1
132#endif // C++11
133
134#endif /* _GLIBCXX_MEMORY */
135