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The C and C++ Include Header Files

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

     1	// POD character, std::char_traits specialization -*- 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	/** @file ext/pod_char_traits.h
    26	 *  This file is a GNU extension to the Standard C++ Library.
    27	 */
    28	
    29	// Gabriel Dos Reis <gdr@integrable-solutions.net>
    30	// Benjamin Kosnik <bkoz@redhat.com>
    31	
    32	#ifndef _POD_CHAR_TRAITS_H
    33	#define _POD_CHAR_TRAITS_H 1
    34	
    35	#ifdef _GLIBCXX_SYSHDR
    36	#pragma GCC system_header
    37	#endif
    38	
    39	#include <bits/requires_hosted.h> // GNU extensions are currently omitted
    40	
    41	#include <string>
    42	
    43	namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
    44	{
    45	_GLIBCXX_BEGIN_NAMESPACE_VERSION
    46	
    47	  // POD character abstraction.
    48	  // NB: The char_type parameter is a subset of int_type, as to allow
    49	  // int_type to properly hold the full range of char_type values as
    50	  // well as EOF.
    51	  /// @brief A POD class that serves as a character abstraction class.
    52	  template<typename _Value, typename _Int, typename _St = std::mbstate_t>
    53	    struct character
    54	    {
    55	      typedef _Value				value_type;
    56	      typedef _Int				int_type;
    57	      typedef _St				state_type;
    58	      typedef character<_Value, _Int, _St>	char_type;
    59	
    60	      value_type	value;
    61	
    62	      template<typename V2>
    63	        static char_type
    64	        from(const V2& v)
    65	        {
    66		  char_type ret = { static_cast<value_type>(v) };
    67		  return ret;
    68		}
    69	
    70	      template<typename V2>
    71	        static V2
    72	        to(const char_type& c)
    73	        {
    74		  V2 ret = { static_cast<V2>(c.value) };
    75		  return ret;
    76		}
    77	
    78	    };
    79	
    80	  template<typename _Value, typename _Int, typename _St>
    81	    inline bool
    82	    operator==(const character<_Value, _Int, _St>& lhs,
    83		       const character<_Value, _Int, _St>& rhs)
    84	    { return lhs.value == rhs.value; }
    85	
    86	  template<typename _Value, typename _Int, typename _St>
    87	    inline bool
    88	    operator<(const character<_Value, _Int, _St>& lhs,
    89		      const character<_Value, _Int, _St>& rhs)
    90	    { return lhs.value < rhs.value; }
    91	
    92	_GLIBCXX_END_NAMESPACE_VERSION
    93	} // namespace
    94	
    95	namespace std _GLIBCXX_VISIBILITY(default)
    96	{
    97	_GLIBCXX_BEGIN_NAMESPACE_VERSION
    98	
    99	  /// char_traits<__gnu_cxx::character> specialization.
   100	  template<typename _Value, typename _Int, typename _St>
   101	    struct char_traits<__gnu_cxx::character<_Value, _Int, _St> >
   102	    {
   103	      typedef __gnu_cxx::character<_Value, _Int, _St>	char_type;
   104	      typedef typename char_type::int_type		int_type;
   105	      typedef typename char_type::state_type		state_type;
   106	      typedef fpos<state_type>				pos_type;
   107	      typedef streamoff					off_type;
   108	
   109	      static void
   110	      assign(char_type& __c1, const char_type& __c2)
   111	      { __c1 = __c2; }
   112	
   113	      static bool
   114	      eq(const char_type& __c1, const char_type& __c2)
   115	      { return __c1 == __c2; }
   116	
   117	      static bool
   118	      lt(const char_type& __c1, const char_type& __c2)
   119	      { return __c1 < __c2; }
   120	
   121	      static int
   122	      compare(const char_type* __s1, const char_type* __s2, size_t __n)
   123	      {
   124		for (size_t __i = 0; __i < __n; ++__i)
   125		  if (!eq(__s1[__i], __s2[__i]))
   126		    return lt(__s1[__i], __s2[__i]) ? -1 : 1;
   127		return 0;
   128	      }
   129	
   130	      static size_t
   131	      length(const char_type* __s)
   132	      {
   133		const char_type* __p = __s;
   134		while (__p->value)
   135		  ++__p;
   136		return (__p - __s);
   137	      }
   138	
   139	      static const char_type*
   140	      find(const char_type* __s, size_t __n, const char_type& __a)
   141	      {
   142		for (const char_type* __p = __s; size_t(__p - __s) < __n; ++__p)
   143		  if (*__p == __a)
   144		    return __p;
   145		return 0;
   146	      }
   147	
   148	      static char_type*
   149	      move(char_type* __s1, const char_type* __s2, size_t __n)
   150	      {
   151		if (__n == 0)
   152		  return __s1;
   153		return static_cast<char_type*>
   154		  (__builtin_memmove(__s1, __s2, __n * sizeof(char_type)));
   155	      }
   156	
   157	      static char_type*
   158	      copy(char_type* __s1, const char_type* __s2, size_t __n)
   159	      {
   160		if (__n == 0)
   161		  return __s1;
   162		std::copy(__s2, __s2 + __n, __s1);
   163		return __s1;
   164	      }
   165	
   166	      static char_type*
   167	      assign(char_type* __s, size_t __n, char_type __a)
   168	      {
   169		std::fill_n(__s, __n, __a);
   170	        return __s;
   171	      }
   172	
   173	      static char_type
   174	      to_char_type(const int_type& __i)
   175	      { return char_type::template from(__i); }
   176	
   177	      static int_type
   178	      to_int_type(const char_type& __c)
   179	      { return char_type::template to<int_type>(__c); }
   180	
   181	      static bool
   182	      eq_int_type(const int_type& __c1, const int_type& __c2)
   183	      { return __c1 == __c2; }
   184	
   185	      static int_type
   186	      eof()
   187	      {
   188		int_type __r = { static_cast<typename __gnu_cxx::__conditional_type
   189				 <std::__is_integer<int_type>::__value,
   190				 int_type, int>::__type>(-1) };
   191		return __r;
   192	      }
   193	
   194	      static int_type
   195	      not_eof(const int_type& __c)
   196	      { return eq_int_type(__c, eof()) ? int_type() : __c; }
   197	    };
   198	
   199	_GLIBCXX_END_NAMESPACE_VERSION
   200	} // namespace
   201	
   202	#endif