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The C and C++ Include Header Files

/usr/include/c++/11/ext/pod_char_traits.h


$ cat -n /usr/include/c++/11/ext/pod_char_traits.h

     1	// POD character, std::char_traits specialization -*- C++ -*-
     2	
     3	// Copyright (C) 2002-2021 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	#pragma GCC system_header
    36	
    37	#include <string>
    38	
    39	namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
    40	{
    41	_GLIBCXX_BEGIN_NAMESPACE_VERSION
    42	
    43	  // POD character abstraction.
    44	  // NB: The char_type parameter is a subset of int_type, as to allow
    45	  // int_type to properly hold the full range of char_type values as
    46	  // well as EOF.
    47	  /// @brief A POD class that serves as a character abstraction class.
    48	  template<typename _Value, typename _Int, typename _St = std::mbstate_t>
    49	    struct character
    50	    {
    51	      typedef _Value				value_type;
    52	      typedef _Int				int_type;
    53	      typedef _St				state_type;
    54	      typedef character<_Value, _Int, _St>	char_type;
    55	
    56	      value_type	value;
    57	
    58	      template<typename V2>
    59	        static char_type
    60	        from(const V2& v)
    61	        {
    62		  char_type ret = { static_cast<value_type>(v) };
    63		  return ret;
    64		}
    65	
    66	      template<typename V2>
    67	        static V2
    68	        to(const char_type& c)
    69	        {
    70		  V2 ret = { static_cast<V2>(c.value) };
    71		  return ret;
    72		}
    73	
    74	    };
    75	
    76	  template<typename _Value, typename _Int, typename _St>
    77	    inline bool
    78	    operator==(const character<_Value, _Int, _St>& lhs,
    79		       const character<_Value, _Int, _St>& rhs)
    80	    { return lhs.value == rhs.value; }
    81	
    82	  template<typename _Value, typename _Int, typename _St>
    83	    inline bool
    84	    operator<(const character<_Value, _Int, _St>& lhs,
    85		      const character<_Value, _Int, _St>& rhs)
    86	    { return lhs.value < rhs.value; }
    87	
    88	_GLIBCXX_END_NAMESPACE_VERSION
    89	} // namespace
    90	
    91	namespace std _GLIBCXX_VISIBILITY(default)
    92	{
    93	_GLIBCXX_BEGIN_NAMESPACE_VERSION
    94	
    95	  /// char_traits<__gnu_cxx::character> specialization.
    96	  template<typename _Value, typename _Int, typename _St>
    97	    struct char_traits<__gnu_cxx::character<_Value, _Int, _St> >
    98	    {
    99	      typedef __gnu_cxx::character<_Value, _Int, _St>	char_type;
   100	      typedef typename char_type::int_type		int_type;
   101	      typedef typename char_type::state_type		state_type;
   102	      typedef fpos<state_type>				pos_type;
   103	      typedef streamoff					off_type;
   104	
   105	      static void
   106	      assign(char_type& __c1, const char_type& __c2)
   107	      { __c1 = __c2; }
   108	
   109	      static bool
   110	      eq(const char_type& __c1, const char_type& __c2)
   111	      { return __c1 == __c2; }
   112	
   113	      static bool
   114	      lt(const char_type& __c1, const char_type& __c2)
   115	      { return __c1 < __c2; }
   116	
   117	      static int
   118	      compare(const char_type* __s1, const char_type* __s2, size_t __n)
   119	      {
   120		for (size_t __i = 0; __i < __n; ++__i)
   121		  if (!eq(__s1[__i], __s2[__i]))
   122		    return lt(__s1[__i], __s2[__i]) ? -1 : 1;
   123		return 0;
   124	      }
   125	
   126	      static size_t
   127	      length(const char_type* __s)
   128	      {
   129		const char_type* __p = __s;
   130		while (__p->value)
   131		  ++__p;
   132		return (__p - __s);
   133	      }
   134	
   135	      static const char_type*
   136	      find(const char_type* __s, size_t __n, const char_type& __a)
   137	      {
   138		for (const char_type* __p = __s; size_t(__p - __s) < __n; ++__p)
   139		  if (*__p == __a)
   140		    return __p;
   141		return 0;
   142	      }
   143	
   144	      static char_type*
   145	      move(char_type* __s1, const char_type* __s2, size_t __n)
   146	      { 
   147		if (__n == 0)
   148		  return __s1;
   149		return static_cast<char_type*>
   150		  (__builtin_memmove(__s1, __s2, __n * sizeof(char_type)));
   151	      }
   152	
   153	      static char_type*
   154	      copy(char_type* __s1, const char_type* __s2, size_t __n)
   155	      {
   156		if (__n == 0)
   157		  return __s1;
   158		std::copy(__s2, __s2 + __n, __s1);
   159		return __s1;
   160	      }
   161	
   162	      static char_type*
   163	      assign(char_type* __s, size_t __n, char_type __a)
   164	      {
   165		std::fill_n(__s, __n, __a);
   166	        return __s;
   167	      }
   168	
   169	      static char_type
   170	      to_char_type(const int_type& __i)
   171	      { return char_type::template from(__i); }
   172	
   173	      static int_type
   174	      to_int_type(const char_type& __c)
   175	      { return char_type::template to<int_type>(__c); }
   176	
   177	      static bool
   178	      eq_int_type(const int_type& __c1, const int_type& __c2)
   179	      { return __c1 == __c2; }
   180	
   181	      static int_type
   182	      eof() 
   183	      {
   184		int_type __r = { static_cast<typename __gnu_cxx::__conditional_type
   185				 <std::__is_integer<int_type>::__value,
   186				 int_type, int>::__type>(-1) };
   187		return __r;
   188	      }
   189	
   190	      static int_type
   191	      not_eof(const int_type& __c)
   192	      { return eq_int_type(__c, eof()) ? int_type() : __c; }
   193	    };
   194	
   195	_GLIBCXX_END_NAMESPACE_VERSION
   196	} // namespace
   197	
   198	#endif