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The C and C++ Include Header Files

cat -n /usr/include/c++/15/ext/vstring_util.h

     1	// Versatile string utility -*- C++ -*-
     2	
     3	// Copyright (C) 2005-2025 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	/** @file ext/vstring_util.h
    26	 *  This is an internal header file, included by other library headers.
    27	 *  Do not attempt to use it directly. @headername{ext/vstring.h}
    28	 */
    29	
    30	#ifndef _VSTRING_UTIL_H
    31	#define _VSTRING_UTIL_H 1
    32	
    33	#ifdef _GLIBCXX_SYSHDR
    34	#pragma GCC system_header
    35	#endif
    36	
    37	#include <bits/requires_hosted.h> // GNU extensions are currently omitted
    38	
    39	#include <ext/vstring_fwd.h>
    40	#include <debug/debug.h>
    41	#include <bits/stl_function.h>  // For less
    42	#include <bits/functexcept.h>
    43	#include <bits/localefwd.h>
    44	#include <bits/ostream_insert.h>
    45	#include <bits/stl_iterator.h>
    46	#include <ext/numeric_traits.h>
    47	#include <ext/alloc_traits.h>
    48	#include <bits/move.h>
    49	#include <bits/range_access.h>
    50	
    51	namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
    52	{
    53	_GLIBCXX_BEGIN_NAMESPACE_VERSION
    54	
    55	  template<typename _CharT, typename _Traits, typename _Alloc>
    56	    struct __vstring_utility
    57	    {
    58	      typedef typename __alloc_traits<_Alloc>::template rebind<_CharT>::other
    59		_CharT_alloc_type;
    60	      typedef __alloc_traits<_CharT_alloc_type> _CharT_alloc_traits;
    61	
    62	      typedef _Traits					    traits_type;
    63	      typedef typename _Traits::char_type		    value_type;
    64	      typedef typename _CharT_alloc_type::size_type	    size_type;
    65	      typedef typename _CharT_alloc_type::difference_type   difference_type;
    66	      typedef typename _CharT_alloc_traits::pointer	    pointer;
    67	      typedef typename _CharT_alloc_traits::const_pointer   const_pointer;
    68	
    69	      // For __sso_string.
    70	      typedef __gnu_cxx::
    71	      __normal_iterator<pointer, __gnu_cxx::
    72				__versa_string<_CharT, _Traits, _Alloc,
    73					       __sso_string_base> >
    74		__sso_iterator;
    75	      typedef __gnu_cxx::
    76	      __normal_iterator<const_pointer, __gnu_cxx::
    77				__versa_string<_CharT, _Traits, _Alloc,
    78					       __sso_string_base> >
    79		__const_sso_iterator;
    80	
    81	      // For __rc_string.
    82	      typedef __gnu_cxx::
    83	      __normal_iterator<pointer, __gnu_cxx::
    84				__versa_string<_CharT, _Traits, _Alloc,
    85					       __rc_string_base> >
    86		__rc_iterator;
    87	      typedef __gnu_cxx::
    88	      __normal_iterator<const_pointer, __gnu_cxx::
    89				__versa_string<_CharT, _Traits, _Alloc,
    90					       __rc_string_base> >
    91		__const_rc_iterator;
    92	
    93	      // NB:  When the allocator is empty, deriving from it saves space
    94	      // (http://www.cantrip.org/emptyopt.html).
    95	      template<typename _Alloc1>
    96		struct _Alloc_hider
    97		: public _Alloc1
    98		{
    99		  _Alloc_hider(_CharT* __ptr)
   100		  : _Alloc1(), _M_p(__ptr) { }
   101	
   102		  _Alloc_hider(const _Alloc1& __a, _CharT* __ptr)
   103		  : _Alloc1(__a), _M_p(__ptr) { }
   104	
   105		  _CharT*  _M_p; // The actual data.
   106		};
   107	
   108	      // When __n = 1 way faster than the general multichar
   109	      // traits_type::copy/move/assign.
   110	      static void
   111	      _S_copy(_CharT* __d, const _CharT* __s, size_type __n)
   112	      {
   113		if (__n == 1)
   114		  traits_type::assign(*__d, *__s);
   115		else
   116		  traits_type::copy(__d, __s, __n);
   117	      }
   118	
   119	      static void
   120	      _S_move(_CharT* __d, const _CharT* __s, size_type __n)
   121	      {
   122		if (__n == 1)
   123		  traits_type::assign(*__d, *__s);
   124		else
   125		  traits_type::move(__d, __s, __n);
   126	      }
   127	
   128	      static void
   129	      _S_assign(_CharT* __d, size_type __n, _CharT __c)
   130	      {
   131		if (__n == 1)
   132		  traits_type::assign(*__d, __c);
   133		else
   134		  traits_type::assign(__d, __n, __c);
   135	      }
   136	
   137	      // _S_copy_chars is a separate template to permit specialization
   138	      // to optimize for the common case of pointers as iterators.
   139	      template<typename _Iterator>
   140		static void
   141		_S_copy_chars(_CharT* __p, _Iterator __k1, _Iterator __k2)
   142		{
   143		  for (; __k1 != __k2; ++__k1, ++__p)
   144		    traits_type::assign(*__p, *__k1); // These types are off.
   145		}
   146	
   147	      static void
   148	      _S_copy_chars(_CharT* __p, __sso_iterator __k1, __sso_iterator __k2)
   149	      { _S_copy_chars(__p, __k1.base(), __k2.base()); }
   150	
   151	      static void
   152	      _S_copy_chars(_CharT* __p, __const_sso_iterator __k1,
   153			    __const_sso_iterator __k2)
   154	      { _S_copy_chars(__p, __k1.base(), __k2.base()); }
   155	
   156	      static void
   157	      _S_copy_chars(_CharT* __p, __rc_iterator __k1, __rc_iterator __k2)
   158	      { _S_copy_chars(__p, __k1.base(), __k2.base()); }
   159	
   160	      static void
   161	      _S_copy_chars(_CharT* __p, __const_rc_iterator __k1,
   162			    __const_rc_iterator __k2)
   163	      { _S_copy_chars(__p, __k1.base(), __k2.base()); }
   164	
   165	      static void
   166	      _S_copy_chars(_CharT* __p, _CharT* __k1, _CharT* __k2)
   167	      { _S_copy(__p, __k1, __k2 - __k1); }
   168	
   169	      static void
   170	      _S_copy_chars(_CharT* __p, const _CharT* __k1, const _CharT* __k2)
   171	      { _S_copy(__p, __k1, __k2 - __k1); }
   172	
   173	      static int
   174	      _S_compare(size_type __n1, size_type __n2)
   175	      {
   176		const difference_type __d = difference_type(__n1 - __n2);
   177	
   178		if (__d > __numeric_traits_integer<int>::__max)
   179		  return __numeric_traits_integer<int>::__max;
   180		else if (__d < __numeric_traits_integer<int>::__min)
   181		  return __numeric_traits_integer<int>::__min;
   182		else
   183		  return int(__d);
   184	      }
   185	    };
   186	
   187	_GLIBCXX_END_NAMESPACE_VERSION
   188	} // namespace
   189	
   190	#endif /* _VSTRING_UTIL_H */