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// Locale support (codecvt) -*- C++ -*-

// Copyright (C) 2000, 2001 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.

//

// ISO C++ 14882: 22.2.1.5 Template class codecvt

//

// Warning: this file is not meant for user inclusion.  Use .

// Written by Benjamin Kosnik 

#ifndef _CPP_BITS_CODECVT_H

#define _CPP_BITS_CODECVT_H	1

#pragma GCC system_header

  // XXX

  // __enc_traits may need to move up the locale header hierarchy,

  // depending on if ctype ends up using it.

#ifdef _GLIBCPP_USE_WCHAR_T

  // Extensions to use icov for dealing with character encodings,

  // including conversions and comparisons between various character

  // sets.  This object encapsulates data that may need to be shared between

  // char_traits, codecvt and ctype.

#if _GLIBCPP_USE_SHADOW_HEADERS

  using _C_legacy::CODESET;

#endif

  class __enc_traits

  {

  public:

    // Types:

    // NB: A conversion descriptor subsumes and enhances the

    // functionality of a simple state type such as mbstate_t.

    typedef iconv_t	__desc_type;

  protected:

    // Data Members:

    // Max size of charset encoding name

    static const int 	_S_max_size = 32;

    // Name of internal character set encoding.

    char	       	_M_int_enc[_S_max_size];

    // Name of external character set encoding.

    char  	       	_M_ext_enc[_S_max_size];

    // Conversion descriptor between external encoding to internal encoding.

    __desc_type		_M_in_desc;

    // Conversion descriptor between internal encoding to external encoding.

    __desc_type		_M_out_desc;

    // Details the byte-order marker for the external encoding, if necessary.

    int			_M_ext_bom;

    // Details the byte-order marker for the internal encoding, if necessary.

    int			_M_int_bom;

  public:

    __enc_traits()

    : _M_in_desc(0), _M_out_desc(0), _M_ext_bom(0), _M_int_bom(0)

    {

      // __intc_end = whatever we are using internally, which is

      // UCS4 (linux)

      // UCS2 == UNICODE  (microsoft, java, aix, whatever...)

      // XXX Currently don't know how to get this data from target system...

      strcpy(_M_int_enc, "UCS4");

      // __extc_end = external codeset in current locale

      strcpy(_M_ext_enc, nl_langinfo(CODESET));

    }

    __enc_traits(const char* __int, const char* __ext, int __ibom = 0,

		 int __ebom = 0)

    : _M_in_desc(0), _M_out_desc(0), _M_ext_bom(0), _M_int_bom(0)

    {

      strncpy(_M_int_enc, __int, _S_max_size);

      strncpy(_M_ext_enc, __ext, _S_max_size);

    }

    // 21.1.2 traits typedefs

    // p4

    // typedef STATE_T state_type

    // requires: state_type shall meet the requirements of

    // CopyConstructible types (20.1.3)

    __enc_traits(const __enc_traits& __obj)

    {

      strncpy(_M_int_enc, __obj._M_int_enc, _S_max_size);

      strncpy(_M_ext_enc, __obj._M_ext_enc, _S_max_size);

      _M_ext_bom = __obj._M_ext_bom;

      _M_int_bom = __obj._M_int_bom;

    }

    ~__enc_traits()

    {

      iconv_close(_M_in_desc);

      iconv_close(_M_out_desc);

    }

    // Initializes

    void

    _M_init()

    {

      _M_in_desc = iconv_open(_M_int_enc, _M_ext_enc);

      _M_out_desc = iconv_open(_M_ext_enc, _M_int_enc);

      if (_M_out_desc == iconv_t(-1) || _M_in_desc == iconv_t(-1))

	{

	  // XXX Extended error checking.

	}

    }

    bool

    _M_good()

    {

      return _M_out_desc && _M_in_desc

	     && _M_out_desc != iconv_t(-1) && _M_in_desc != iconv_t(-1);

    }

    const __desc_type*

    _M_get_in_descriptor()

    { return &_M_in_desc; }

    const __desc_type*

    _M_get_out_descriptor()

    { return &_M_out_desc; }

   const char*

    _M_get_internal_enc()

    { return _M_int_enc; }

    const char*

    _M_get_external_enc()

    { return _M_ext_enc; }

    int

    _M_get_external_bom()

    { return _M_ext_bom; }

    int

    _M_get_internal_bom()

    { return _M_int_bom; }

  };

#endif //_GLIBCPP_USE_WCHAR_T

  //  22.2.1.5  Template class codecvt

  class codecvt_base

  {

  public:

    enum result

    {

      ok,

      partial,

      error,

      noconv

    };

  };

  // Template class __codecvt_abstract_base

  // NB: An abstract base class that fills in the public inlines, so

  // that the specializations don't have to re-copy the public

  // interface.

  template

    class __codecvt_abstract_base

    : public locale::facet, public codecvt_base

    {

    public:

      // Types:

      typedef codecvt_base::result			result;

      typedef _InternT 					intern_type;

      typedef _ExternT 					extern_type;

      typedef _StateT  					state_type;

      // 22.2.1.5.1 codecvt members

      result

      out(state_type& __state, const intern_type* __from,

	  const intern_type* __from_end, const intern_type*& __from_next,

	  extern_type* __to, extern_type* __to_end,

	  extern_type*& __to_next) const

      {

	return this->do_out(__state, __from, __from_end, __from_next,

			    __to, __to_end, __to_next);

      }

      result

      unshift(state_type& __state, extern_type* __to, extern_type* __to_end,

	      extern_type*& __to_next) const

      { return this->do_unshift(__state, __to,__to_end,__to_next); }

      result

      in(state_type& __state, const extern_type* __from,

	 const extern_type* __from_end, const extern_type*& __from_next,

	 intern_type* __to, intern_type* __to_end,

	 intern_type*& __to_next) const

      {

	return this->do_in(__state, __from, __from_end, __from_next,

			   __to, __to_end, __to_next);

      }

      int

      encoding() const throw()

      { return this->do_encoding(); }

      bool

      always_noconv() const throw()

      { return this->do_always_noconv(); }

      int

      length(const state_type& __state, const extern_type* __from,

	     const extern_type* __end, size_t __max) const

      { return this->do_length(__state, __from, __end, __max); }

      int

      max_length() const throw()

      { return this->do_max_length(); }

    protected:

      explicit

      __codecvt_abstract_base(size_t __refs = 0) : locale::facet(__refs) { }

      virtual

      ~__codecvt_abstract_base() { }

      virtual result

      do_out(state_type& __state, const intern_type* __from,

	     const intern_type* __from_end, const intern_type*& __from_next,

	     extern_type* __to, extern_type* __to_end,

	     extern_type*& __to_next) const = 0;

      virtual result

      do_unshift(state_type& __state, extern_type* __to,

		 extern_type* __to_end, extern_type*& __to_next) const = 0;

      virtual result

      do_in(state_type& __state, const extern_type* __from,

	    const extern_type* __from_end, const extern_type*& __from_next,

	    intern_type* __to, intern_type* __to_end,

	    intern_type*& __to_next) const = 0;

      virtual int

      do_encoding() const throw() = 0;

      virtual bool

      do_always_noconv() const throw() = 0;

      virtual int

      do_length(const state_type&, const extern_type* __from,

		const extern_type* __end, size_t __max) const = 0;

      virtual int

      do_max_length() const throw() = 0;

    };

  // 22.2.1.5 Template class codecvt

  // NB: Generic, mostly useless implementation.

  template

    class codecvt

    : public __codecvt_abstract_base<_InternT, _ExternT, _StateT>

    {

    public:

      // Types:

      typedef codecvt_base::result			result;

      typedef _InternT intern_type;

      typedef _ExternT extern_type;

      typedef _StateT  state_type;

      // Data Members:

      static locale::id id;

      explicit

      codecvt(size_t __refs = 0)

      : __codecvt_abstract_base<_InternT,_ExternT,_StateT> (__refs) { }

    protected:

      virtual

      ~codecvt() { }

    };

  template

    locale::id codecvt<_InternT, _ExternT, _StateT>::id;

#ifdef _GLIBCPP_USE_WCHAR_T

  // partial specialization

  // This specialization takes advantage of iconv to provide code

  // conversions between a large number of character encodings.

  template

    class codecvt<_InternT, _ExternT, __enc_traits>

    : public __codecvt_abstract_base<_InternT, _ExternT, __enc_traits>

    {

    public:

      // Types:

      typedef codecvt_base::result			result;

      typedef _InternT 					intern_type;

      typedef _ExternT 					extern_type;

      typedef __enc_traits 				state_type;

      typedef __enc_traits::__desc_type 		__desc_type;

      typedef __enc_traits				__enc_type;

      // Data Members:

      static locale::id 		id;

      explicit

      codecvt(size_t __refs = 0)

      : __codecvt_abstract_base(__refs)

      { }

      explicit

      codecvt(__enc_type* __enc, size_t __refs = 0)

      : __codecvt_abstract_base(__refs)

      { }

    protected:

      virtual

      ~codecvt() { }

      virtual result

      do_out(state_type& __state, const intern_type* __from,

	     const intern_type* __from_end, const intern_type*& __from_next,

	     extern_type* __to, extern_type* __to_end,

	     extern_type*& __to_next) const;

      virtual result

      do_unshift(state_type& __state, extern_type* __to,

		 extern_type* __to_end, extern_type*& __to_next) const;

      virtual result

      do_in(state_type& __state, const extern_type* __from,

	    const extern_type* __from_end, const extern_type*& __from_next,

	    intern_type* __to, intern_type* __to_end,

	    intern_type*& __to_next) const;

      virtual int

      do_encoding() const throw();

      virtual bool

      do_always_noconv() const throw();

      virtual int

      do_length(const state_type&, const extern_type* __from,

		const extern_type* __end, size_t __max) const;

      virtual int

      do_max_length() const throw();

    };

  template

    locale::id

    codecvt<_InternT, _ExternT, __enc_traits>::id;

  // This adaptor works around the signature problems of the second

  // argument to iconv():  SUSv2 and others use 'const char**', but glibc 2.2

  // uses 'char**', which is what the standard is (apparently) due to use

  // in the future.  Using this adaptor, g++ will do the work for us.

  template

    inline size_t

    __iconv_adaptor(size_t(*iconv_func)(iconv_t, _T, size_t*, char**, size_t*),

                    iconv_t cd, char** inbuf, size_t* inbytesleft,

                    char** outbuf, size_t* outbytesleft)

    {

      return iconv_func(cd, (_T)inbuf, inbytesleft, outbuf, outbytesleft);

    }

  template

    codecvt_base::result

    codecvt<_InternT, _ExternT, __enc_traits>::

    do_out(state_type& __state, const intern_type* __from,

	   const intern_type* __from_end, const intern_type*& __from_next,

	   extern_type* __to, extern_type* __to_end,

	   extern_type*& __to_next) const

    {

      result __ret = error;

      if (__state._M_good())

	{

	  typedef state_type::__desc_type	__desc_type;

	  const __desc_type* __desc = __state._M_get_out_descriptor();

	  const size_t __fmultiple = sizeof(intern_type) / sizeof(char);

	  size_t __flen = __fmultiple * (__from_end - __from);

	  const size_t __tmultiple = sizeof(extern_type) / sizeof(char);

	  size_t __tlen = __tmultiple * (__to_end - __to);

	  // Argument list for iconv specifies a byte sequence. Thus,

	  // all to/from arrays must be brutally casted to char*.

	  char* __cto = reinterpret_cast(__to);

	  char* __cfrom;

	  size_t __conv;

	  // Some encodings need a byte order marker as the first item

	  // in the byte stream, to designate endian-ness. The default

	  // value for the byte order marker is NULL, so if this is

	  // the case, it's not necessary and we can just go on our

	  // merry way.

	  int __int_bom = __state._M_get_internal_bom();

	  if (__int_bom)

	    {

	      size_t __size = __from_end - __from;

	      intern_type* __cfixed = static_cast(__builtin_alloca(sizeof(intern_type) * (__size + 1)));

	      __cfixed[0] = static_cast(__int_bom);

	      char_traits::copy(__cfixed + 1, __from, __size);

	      __cfrom = reinterpret_cast(__cfixed);

	      __conv = __iconv_adaptor(iconv, *__desc, &__cfrom,

                                        &__flen, &__cto, &__tlen);

	    }

	  else

	    {

	      intern_type* __cfixed = const_cast(__from);

	      __cfrom = reinterpret_cast(__cfixed);

	      __conv = __iconv_adaptor(iconv, *__desc, &__cfrom,

                                       &__flen, &__cto, &__tlen);

	    }

	  if (__conv != size_t(-1))

	    {

	      __from_next = reinterpret_cast(__cfrom);

	      __to_next = reinterpret_cast(__cto);

	      __ret = ok;

	    }

	  else

	    {

	      if (__flen < static_cast(__from_end - __from))

		{

		  __from_next = reinterpret_cast(__cfrom);

		  __to_next = reinterpret_cast(__cto);

		  __ret = partial;

		}

	      else

		__ret = error;

	    }

	}

      return __ret;

    }

  template

    codecvt_base::result

    codecvt<_InternT, _ExternT, __enc_traits>::

    do_unshift(state_type& __state, extern_type* __to,

	       extern_type* __to_end, extern_type*& __to_next) const

    {

      result __ret = error;

      if (__state._M_good())

	{

	  typedef state_type::__desc_type	__desc_type;

	  const __desc_type* __desc = __state._M_get_in_descriptor();

	  const size_t __tmultiple = sizeof(intern_type) / sizeof(char);

	  size_t __tlen = __tmultiple * (__to_end - __to);

	  // Argument list for iconv specifies a byte sequence. Thus,

	  // all to/from arrays must be brutally casted to char*.

	  char* __cto = reinterpret_cast(__to);

	  size_t __conv = __iconv_adaptor(iconv,*__desc, NULL, NULL,

                                          &__cto, &__tlen);

	  if (__conv != size_t(-1))

	    {

	      __to_next = reinterpret_cast(__cto);

	      if (__tlen == __tmultiple * (__to_end - __to))

		__ret = noconv;

	      else if (__tlen == 0)

		__ret = ok;

	      else

		__ret = partial;

	    }

	  else

	    __ret = error;

	}

      return __ret;

    }

  template

    codecvt_base::result

    codecvt<_InternT, _ExternT, __enc_traits>::

    do_in(state_type& __state, const extern_type* __from,

	  const extern_type* __from_end, const extern_type*& __from_next,

	  intern_type* __to, intern_type* __to_end,

	  intern_type*& __to_next) const

    {

      result __ret = error;

      if (__state._M_good())

	{

	  typedef state_type::__desc_type	__desc_type;

	  const __desc_type* __desc = __state._M_get_in_descriptor();

	  const size_t __fmultiple = sizeof(extern_type) / sizeof(char);

	  size_t __flen = __fmultiple * (__from_end - __from);

	  const size_t __tmultiple = sizeof(intern_type) / sizeof(char);

	  size_t __tlen = __tmultiple * (__to_end - __to);

	  // Argument list for iconv specifies a byte sequence. Thus,

	  // all to/from arrays must be brutally casted to char*.

	  char* __cto = reinterpret_cast(__to);

	  char* __cfrom;

	  size_t __conv;

	  // Some encodings need a byte order marker as the first item

	  // in the byte stream, to designate endian-ness. The default

	  // value for the byte order marker is NULL, so if this is

	  // the case, it's not necessary and we can just go on our

	  // merry way.

	  int __ext_bom = __state._M_get_external_bom();

	  if (__ext_bom)

	    {

	      size_t __size = __from_end - __from;

	      extern_type* __cfixed =  static_cast(__builtin_alloca(sizeof(extern_type) * (__size + 1)));

	      __cfixed[0] = static_cast(__ext_bom);

	      char_traits::copy(__cfixed + 1, __from, __size);

	      __cfrom = reinterpret_cast(__cfixed);

	      __conv = __iconv_adaptor(iconv, *__desc, &__cfrom,

                                       &__flen, &__cto, &__tlen);

	    }

	  else

	    {

	      extern_type* __cfixed = const_cast(__from);

	      __cfrom = reinterpret_cast(__cfixed);

	      __conv = __iconv_adaptor(iconv, *__desc, &__cfrom,

                                       &__flen, &__cto, &__tlen);

	    }

	  if (__conv != size_t(-1))

	    {

	      __from_next = reinterpret_cast(__cfrom);

	      __to_next = reinterpret_cast(__cto);

	      __ret = ok;

	    }

	  else

	    {

	      if (__flen < static_cast(__from_end - __from))

		{

		  __from_next = reinterpret_cast(__cfrom);

		  __to_next = reinterpret_cast(__cto);

		  __ret = partial;

		}

	      else

		__ret = error;

	    }

	}

      return __ret;

    }

  template

    int

    codecvt<_InternT, _ExternT, __enc_traits>::

    do_encoding() const throw()

    { return 0; }

  template

    bool

    codecvt<_InternT, _ExternT, __enc_traits>::

    do_always_noconv() const throw()

    { return false; }

  template

    int

    codecvt<_InternT, _ExternT, __enc_traits>::

    do_length(const state_type&, const extern_type* __from,

	      const extern_type* __end, size_t __max) const

    { return min(__max, static_cast(__end - __from)); }

#ifdef _GLIBCPP_RESOLVE_LIB_DEFECTS

// 74.  Garbled text for codecvt::do_max_length

  template

    int

    codecvt<_InternT, _ExternT, __enc_traits>::

    do_max_length() const throw()

    { return 1; }

#endif

#endif /* _GLIBCPP_USE_WCHAR_T */

  // codecvt required specialization

  template<>

    class codecvt

    : public __codecvt_abstract_base

    {

    public:

      // Types:

      typedef char 	intern_type;

      typedef char 	extern_type;

      typedef mbstate_t state_type;

      // Data Members:

      static locale::id id;

      explicit

      codecvt(size_t __refs = 0);

    protected:

      virtual

      ~codecvt();

      virtual result

      do_out(state_type& __state, const intern_type* __from,

	     const intern_type* __from_end, const intern_type*& __from_next,

	     extern_type* __to, extern_type* __to_end,

	     extern_type*& __to_next) const;

      virtual result

      do_unshift(state_type& __state, extern_type* __to,

		 extern_type* __to_end, extern_type*& __to_next) const;

      virtual result

      do_in(state_type& __state, const extern_type* __from,

	    const extern_type* __from_end, const extern_type*& __from_next,

	    intern_type* __to, intern_type* __to_end,

	    intern_type*& __to_next) const;

      virtual int

      do_encoding() const throw();

      virtual bool

      do_always_noconv() const throw();

      virtual int

      do_length(const state_type&, const extern_type* __from,

		const extern_type* __end, size_t __max) const;

      virtual int

      do_max_length() const throw();

  };

#ifdef _GLIBCPP_USE_WCHAR_T

  // codecvt required specialization

  template<>

    class codecvt

    : public __codecvt_abstract_base

    {

    public:

      // Types:

      typedef wchar_t 	intern_type;

      typedef char 	extern_type;

      typedef mbstate_t state_type;

      // Data Members:

      static locale::id id;

      explicit

      codecvt(size_t __refs = 0);

    protected:

      virtual

      ~codecvt();

      virtual result

      do_out(state_type& __state, const intern_type* __from,

	     const intern_type* __from_end, const intern_type*& __from_next,

	     extern_type* __to, extern_type* __to_end,

	     extern_type*& __to_next) const;

      virtual result

      do_unshift(state_type& __state,

		 extern_type* __to, extern_type* __to_end,

		 extern_type*& __to_next) const;

      virtual result

      do_in(state_type& __state,

	     const extern_type* __from, const extern_type* __from_end,

	     const extern_type*& __from_next,

	     intern_type* __to, intern_type* __to_end,

	     intern_type*& __to_next) const;

      virtual

      int do_encoding() const throw();

      virtual

      bool do_always_noconv() const throw();

      virtual

      int do_length(const state_type&, const extern_type* __from,

		    const extern_type* __end, size_t __max) const;

      virtual int

      do_max_length() const throw();

    };

#endif //_GLIBCPP_USE_WCHAR_T

  // 22.2.1.6  Template class codecvt_byname

  template

    class codecvt_byname : public codecvt<_InternT, _ExternT, _StateT>

    {

    public:

      explicit

      codecvt_byname(const char*, size_t __refs = 0)

      : codecvt<_InternT, _ExternT, _StateT>(__refs) { }

    protected:

      virtual

      ~codecvt_byname() { }

    };

#endif // _CPP_BITS_CODECVT_H

// Local Variables:

// mode:c++

// End: