Boost C++ Libraries

libs/filesystem/src/windows_file_codecvt.hpp

//  filesystem windows_file_codecvt.hpp  -----------------------------------------------//

//  Copyright Beman Dawes 2009

//  Distributed under the Boost Software License, Version 1.0.
//  See http://www.boost.org/LICENSE_1_0.txt

//  Library home page: http://www.boost.org/libs/filesystem

#ifndef BOOST_FILESYSTEM3_WIN_FILE_CODECVT_HPP
#define BOOST_FILESYSTEM3_WIN_FILE_CODECVT_HPP

#include <boost/filesystem/config.hpp>
#include <cstddef>
#include <locale>

//------------------------------------------------------------------------------------//
//                                                                                    //
//                          class windows_file_codecvt                                //
//                                                                                    //
//  Warning: partial implementation; even do_in and do_out only partially meet the    //
//  standard library specifications as the "to" buffer must hold the entire result.   //
//                                                                                    //
//------------------------------------------------------------------------------------//

class BOOST_SYMBOL_VISIBLE windows_file_codecvt
  : public std::codecvt< wchar_t, char, std::mbstate_t >
{
public:
  explicit windows_file_codecvt(std::size_t refs = 0)
      : std::codecvt<wchar_t, char, std::mbstate_t>(refs) {}
protected:

  virtual bool do_always_noconv() const throw() { return false; }

  //  seems safest to assume variable number of characters since we don't
  //  actually know what codepage is active
  virtual int do_encoding() const throw() { return 0; }

  virtual std::codecvt_base::result do_in(std::mbstate_t& state,
    const char* from, const char* from_end, const char*& from_next,
    wchar_t* to, wchar_t* to_end, wchar_t*& to_next) const;

  virtual std::codecvt_base::result do_out(std::mbstate_t & state,
    const wchar_t* from, const wchar_t* from_end, const wchar_t*& from_next,
    char* to, char* to_end, char*& to_next) const;

  virtual std::codecvt_base::result do_unshift(std::mbstate_t&,
      char* /*from*/, char* /*to*/, char* & /*next*/) const  { return ok; }

  virtual int do_length(std::mbstate_t&,
    const char* /*from*/, const char* /*from_end*/, std::size_t /*max*/) const  { return 0; }

  virtual int do_max_length() const throw () { return 0; }
};

#endif  // BOOST_FILESYSTEM3_WIN_FILE_CODECVT_HPP