pod_char_traits.h   [plain text]

// POD character, std::char_traits specialization -*- C++ -*-

// Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2, or (at your option)
// any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING.  If not, write to the Free
// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
// USA.

// As a special exception, you may use this file as part of a free software
// library without restriction.  Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License.  This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.

/** @file ext/pod_char_traits.h
 *  This file is a GNU extension to the Standard C++ Library.
 */

// Gabriel Dos Reis <gdr@integrable-solutions.net>
// Benjamin Kosnik <bkoz@redhat.com>

#ifndef _POD_CHAR_TRAITS_H
#define _POD_CHAR_TRAITS_H 1

#include <string>

namespace __gnu_cxx
{
  /// @brief A POD class that serves as a character abstraction class.
  template<typename V, typename I, typename S = mbstate_t>
    struct character
    {
      typedef V		value_type;
      typedef I		int_type;
      typedef S		state_type;
      value_type	value;
    };

  template<typename V, typename I>
    inline bool
    operator==(const character<V, I>& lhs, const character<V, I>& rhs)
    { return lhs.value == rhs.value; }

  template<typename V, typename I>
    inline bool
    operator<(const character<V, I>& lhs, const character<V, I>& rhs)
    { return lhs.value < rhs.value; }
} // namespace __gnu_cxx

namespace std
{
  /// char_traits<__gnu_cxx::character> specialization.
  template<typename V, typename I, typename S>
    struct char_traits<__gnu_cxx::character<V, I, S> >
    {
      typedef __gnu_cxx::character<V, I, S>	char_type;

      // NB: This type should be bigger than char_type, so as to
      // properly hold EOF values in addition to the full range of
      // char_type values.
      // Also, assumes
      // int_type(value_type) is valid.
      // int_type(-1) is possible.
      typedef typename char_type::int_type	int_type;
      typedef typename char_type::state_type	state_type;
      typedef fpos<state_type>			pos_type;
      typedef streamoff				off_type;

      static void
      assign(char_type& __c1, const char_type& __c2)
      { __c1 = __c2; }

      static bool
      eq(const char_type& __c1, const char_type& __c2)
      { return __c1 == __c2; }

      static bool
      lt(const char_type& __c1, const char_type& __c2)
      { return __c1 < __c2; }

      static int
      compare(const char_type* __s1, const char_type* __s2, size_t __n)
      {
	for (size_t __i = 0; __i < __n; ++__i)
	  if (!eq(__s1[__i], __s2[__i]))
	    return lt(__s1[__i], __s2[__i]) ? -1 : 1;
	return 0;
      }

      static size_t
      length(const char_type* __s)
      {
	const char_type* __p = __s;
	while (__p->value)
	  ++__p;
	return (__p - __s);
      }

      static const char_type*
      find(const char_type* __s, size_t __n, const char_type& __a)
      {
	for (const char_type* __p = __s; size_t(__p - __s) < __n; ++__p)
	  if (*__p == __a)
	    return __p;
	return 0;
      }

      static char_type*
      move(char_type* __s1, const char_type* __s2, size_t __n)
      { return (char_type*) memmove(__s1, __s2, __n * sizeof(char_type)); }

      static char_type*
      copy(char_type* __s1, const char_type* __s2, size_t __n)
      { return (char_type*) memcpy(__s1, __s2, __n * sizeof(char_type)); }

      static char_type*
      assign(char_type* __s, size_t __n, char_type __a)
      {
	for (char_type* __p = __s; __p < __s + __n; ++__p)
	  assign(*__p, __a);
        return __s;
      }

      static char_type
      to_char_type(const int_type& __c)
      {
	char_type __r = { __c };
	return __r;
      }

      static int_type
      to_int_type(const char_type& __c)
      { return int_type(__c.value); }

      static bool
      eq_int_type(const int_type& __c1, const int_type& __c2)
      { return __c1 == __c2; }

      static int_type
      eof() { return static_cast<int_type>(-1); }

      static int_type
      not_eof(const int_type& __c)
      { return eq_int_type(__c, eof()) ? int_type(0) : __c; }
    };
}

#endif