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The C and C++ Include Header Files

cat -n /usr/include/c++/15/ext/memory

     1	// Memory extensions -*- C++ -*-
     2	
     3	// Copyright (C) 2002-2025 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	 *
    27	 * Copyright (c) 1994
    28	 * Hewlett-Packard Company
    29	 *
    30	 * Permission to use, copy, modify, distribute and sell this software
    31	 * and its documentation for any purpose is hereby granted without fee,
    32	 * provided that the above copyright notice appear in all copies and
    33	 * that both that copyright notice and this permission notice appear
    34	 * in supporting documentation.  Hewlett-Packard Company makes no
    35	 * representations about the suitability of this software for any
    36	 * purpose.  It is provided "as is" without express or implied warranty.
    37	 *
    38	 *
    39	 * Copyright (c) 1996
    40	 * Silicon Graphics Computer Systems, Inc.
    41	 *
    42	 * Permission to use, copy, modify, distribute and sell this software
    43	 * and its documentation for any purpose is hereby granted without fee,
    44	 * provided that the above copyright notice appear in all copies and
    45	 * that both that copyright notice and this permission notice appear
    46	 * in supporting documentation.  Silicon Graphics makes no
    47	 * representations about the suitability of this software for any
    48	 * purpose.  It is provided "as is" without express or implied warranty.
    49	 */
    50	
    51	/** @file ext/memory
    52	 *  This file is a GNU extension to the Standard C++ Library (possibly
    53	 *  containing extensions from the HP/SGI STL subset).
    54	 */
    55	
    56	#ifndef _EXT_MEMORY
    57	#define _EXT_MEMORY 1
    58	
    59	#ifdef _GLIBCXX_SYSHDR
    60	#pragma GCC system_header
    61	#endif
    62	
    63	#include <bits/requires_hosted.h> // GNU extensions are currently omitted
    64	
    65	#include <memory>
    66	#include <bits/stl_tempbuf.h>
    67	
    68	namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
    69	{
    70	_GLIBCXX_BEGIN_NAMESPACE_VERSION
    71	
    72	  using std::_Temporary_buffer;
    73	
    74	  template<typename _InputIter, typename _Size, typename _ForwardIter>
    75	    std::pair<_InputIter, _ForwardIter>
    76	    __uninitialized_copy_n(_InputIter __first, _Size __count,
    77				   _ForwardIter __result, std::input_iterator_tag)
    78	    {
    79	      _ForwardIter __cur = __result;
    80	      __try
    81		{
    82		  for (; __count > 0 ; --__count, ++__first, ++__cur)
    83		    std::_Construct(&*__cur, *__first);
    84		  return std::pair<_InputIter, _ForwardIter>(__first, __cur);
    85		}
    86	      __catch(...)
    87		{
    88		  std::_Destroy(__result, __cur);
    89		  __throw_exception_again;
    90		}
    91	    }
    92	
    93	  template<typename _RandomAccessIter, typename _Size, typename _ForwardIter>
    94	    inline std::pair<_RandomAccessIter, _ForwardIter>
    95	    __uninitialized_copy_n(_RandomAccessIter __first, _Size __count,
    96				   _ForwardIter __result,
    97				   std::random_access_iterator_tag)
    98	    {
    99	      _RandomAccessIter __last = __first + __count;
   100	      return (std::pair<_RandomAccessIter, _ForwardIter>
   101		      (__last, std::uninitialized_copy(__first, __last, __result)));
   102	    }
   103	
   104	  template<typename _InputIter, typename _Size, typename _ForwardIter>
   105	    inline std::pair<_InputIter, _ForwardIter>
   106	    __uninitialized_copy_n(_InputIter __first, _Size __count,
   107				   _ForwardIter __result)
   108	    {
   109	      return __gnu_cxx::__uninitialized_copy_n(__first, __count, __result,
   110		  std::__iterator_category(__first));
   111	    }
   112	
   113	  /**
   114	   *  @brief Copies the range [first,last) into result.
   115	   *  @param  __first  An input iterator.
   116	   *  @param  __count  Length
   117	   *  @param  __result An output iterator.
   118	   *  @return   __result + (__first + __count)
   119	   *  @ingroup SGIextensions
   120	   *
   121	   *  Like copy(), but does not require an initialized output range.
   122	  */
   123	  template<typename _InputIter, typename _Size, typename _ForwardIter>
   124	    inline std::pair<_InputIter, _ForwardIter>
   125	    uninitialized_copy_n(_InputIter __first, _Size __count,
   126				 _ForwardIter __result)
   127	    {
   128	      return __gnu_cxx::__uninitialized_copy_n(__first, __count, __result,
   129		  std::__iterator_category(__first));
   130	    }
   131	
   132	
   133	  // An alternative version of uninitialized_copy_n that constructs
   134	  // and destroys objects with a user-provided allocator.
   135	  template<typename _InputIter, typename _Size, typename _ForwardIter,
   136	           typename _Allocator>
   137	    std::pair<_InputIter, _ForwardIter>
   138	    __uninitialized_copy_n_a(_InputIter __first, _Size __count,
   139				     _ForwardIter __result,
   140				     _Allocator __alloc)
   141	    {
   142	      _ForwardIter __cur = __result;
   143	      __try
   144		{
   145		  for (; __count > 0 ; --__count, ++__first, ++__cur)
   146		    __alloc.construct(&*__cur, *__first);
   147		  return std::pair<_InputIter, _ForwardIter>(__first, __cur);
   148		}
   149	      __catch(...)
   150		{
   151		  std::_Destroy(__result, __cur, __alloc);
   152		  __throw_exception_again;
   153		}
   154	    }
   155	
   156	  template<typename _InputIter, typename _Size, typename _ForwardIter,
   157	           typename _Tp>
   158	    inline std::pair<_InputIter, _ForwardIter>
   159	    __uninitialized_copy_n_a(_InputIter __first, _Size __count,
   160				     _ForwardIter __result,
   161				     std::allocator<_Tp>)
   162	    {
   163	      return __gnu_cxx::uninitialized_copy_n(__first, __count, __result);
   164	    }
   165	
   166	  /**
   167	   *  This class provides similar behavior and semantics of the standard
   168	   *  functions get_temporary_buffer() and return_temporary_buffer(), but
   169	   *  encapsulated in a type vaguely resembling a standard container.
   170	   *
   171	   *  By default, a temporary_buffer<Iter> stores space for objects of
   172	   *  whatever type the Iter iterator points to.  It is constructed from a
   173	   *  typical [first,last) range, and provides the begin(), end(), size()
   174	   *  functions, as well as requested_size().  For non-trivial types, copies
   175	   *  of *first will be used to initialize the storage.
   176	   *
   177	   *  @c malloc is used to obtain underlying storage.
   178	   *
   179	   *  Like get_temporary_buffer(), not all the requested memory may be
   180	   *  available.  Ideally, the created buffer will be large enough to hold a
   181	   *  copy of [first,last), but if size() is less than requested_size(),
   182	   *  then this didn't happen.
   183	   *
   184	   *  @ingroup SGIextensions
   185	  */
   186	  template <class _ForwardIterator, class _Tp
   187		    = typename std::iterator_traits<_ForwardIterator>::value_type >
   188	    struct temporary_buffer : public _Temporary_buffer<_ForwardIterator, _Tp>
   189	    {
   190	      /// Requests storage large enough to hold a copy of [first,last).
   191	      temporary_buffer(_ForwardIterator __first, _ForwardIterator __last)
   192	      : _Temporary_buffer<_ForwardIterator, _Tp>(__first,
   193							 std::distance(__first, __last))
   194	      { }
   195	      
   196	      /// Destroys objects and frees storage.
   197	      ~temporary_buffer() { }
   198	    };
   199	
   200	_GLIBCXX_END_NAMESPACE_VERSION
   201	} // namespace
   202	
   203	#endif
   204