/*

 * Portions Copyright (c) 2008 Nokia Corporation and/or its subsidiary(-ies). All rights reserved.

 *

 * Copyright (c) 1999

 * Silicon Graphics Computer Systems, Inc.

 *

 * Copyright (c) 1999

 * Boris Fomitchev

 *

 * This material is provided "as is", with absolutely no warranty expressed

 * or implied. Any use is at your own risk.

 *

 * Permission to use or copy this software for any purpose is hereby granted

 * without fee, provided the above notices are retained on all copies.

 * Permission to modify the code and to distribute modified code is granted,

 * provided the above notices are retained, and a notice that the code was

 * modified is included with the above copyright notice.

 *

 */

// This header defines classes basic_filebuf, basic_ifstream,

// basic_ofstream, and basic_fstream.  These classes represent

// streambufs and streams whose sources or destinations are files.

#ifndef _STLP_INTERNAL_FSTREAM_H

#define _STLP_INTERNAL_FSTREAM_H

#if defined(__sgi) && !defined(__GNUC__) && !defined(_STANDARD_C_PLUS_PLUS)

#  error This header file requires the -LANG:std option

#endif

#ifndef _STLP_INTERNAL_STREAMBUF

#  include <stl/_streambuf.h>

#endif

#ifndef _STLP_INTERNAL_ISTREAM

#  include <stl/_istream.h>

#endif

#ifndef _STLP_INTERNAL_CODECVT_H

#  include <stl/_codecvt.h>

#endif

#if !defined (_STLP_USE_UNIX_IO) && !defined(_STLP_USE_WIN32_IO) && \

    !defined (_STLP_USE_UNIX_EMULATION_IO) && !defined (_STLP_USE_STDIO_IO)

#  if defined (_STLP_UNIX)  || defined (__CYGWIN__) || defined (__amigaos__) || defined (__EMX__)

// open/close/read/write

#    define _STLP_USE_UNIX_IO

#  elif defined (_STLP_WIN32) && !defined (__SYMBIAN32__)

// CreateFile/ReadFile/WriteFile

#    define _STLP_USE_WIN32_IO

#  elif defined (_STLP_WIN16) || defined (_STLP_MAC)

// _open/_read/_write

#    define _STLP_USE_UNIX_EMULATION_IO

#  else

// fopen/fread/fwrite

#    define _STLP_USE_STDIO_IO

#  endif /* _STLP_UNIX */

#endif /* mode selection */

#if defined (_STLP_USE_WIN32_IO)

typedef void* _STLP_fd;

#elif defined (_STLP_USE_UNIX_EMULATION_IO) || defined (_STLP_USE_STDIO_IO) || defined (_STLP_USE_UNIX_IO)

typedef int _STLP_fd;

#else

#  error "Configure i/o !"

#endif

#if defined(__SYMBIAN32__WSD__)

size_t& get_fstream_Filebuf_Base_GetPageSize();

#define _M_page_size  get_fstream_Filebuf_Base_GetPageSize()

#endif //__SYMBIAN32__WSD__

_STLP_BEGIN_NAMESPACE

//----------------------------------------------------------------------

// Class _Filebuf_base, a private base class to factor out the system-

// dependent code from basic_filebuf<>.

class _STLP_CLASS_DECLSPEC _Filebuf_base {

public:                      // Opening and closing files.

  _STLP_DECLSPEC _Filebuf_base();

  _STLP_DECLSPEC bool _M_open(const char*, ios_base::openmode, long __protection);

  _STLP_DECLSPEC bool _M_open(const char*, ios_base::openmode);

  _STLP_DECLSPEC bool _M_open(int __id, ios_base::openmode = ios_base::__default_mode);

#if defined (_STLP_USE_WIN32_IO)

  bool _M_open(_STLP_fd __id, ios_base::openmode = ios_base::__default_mode);

#endif /* _STLP_USE_WIN32_IO */

  _STLP_DECLSPEC bool _M_close();

public:                      // Low-level I/O, like Unix read/write

  _STLP_DECLSPEC ptrdiff_t _M_read(char* __buf,  ptrdiff_t __n);

  _STLP_DECLSPEC streamoff _M_seek(streamoff __offset, ios_base::seekdir __dir);

  _STLP_DECLSPEC streamoff _M_file_size();

  _STLP_DECLSPEC bool _M_write(char* __buf,  ptrdiff_t __n);

public:                      // Memory-mapped I/O.

  _STLP_DECLSPEC void* _M_mmap(streamoff __offset, streamoff __len);

  _STLP_DECLSPEC void _M_unmap(void* __mmap_base, streamoff __len);

public:

  // Returns a value n such that, if pos is the file pointer at the

  // beginning of the range [first, last), pos + n is the file pointer at

  // the end.  On many operating systems n == __last - __first.

  // In Unix, writing n characters always bumps the file position by n.

  // In Windows text mode, however, it bumps the file position by n + m,

  // where m is the number of newlines in the range.  That's because an

  // internal \n corresponds to an external two-character sequence.

  streamoff _M_get_offset(char* __first, char* __last) {

#if defined (_STLP_UNIX) || defined (_STLP_MAC)

    return __last - __first;

#else // defined (_STLP_WIN32) || defined (_STLP_WIN16) || defined (_STLP_DOS) || defined(N_PLAT_NLM)

    return ( (_M_openmode & ios_base::binary) != 0 )

      ? (__last - __first)

      : count(__first, __last, '\n') + (__last - __first);

#endif

  }

  // Returns true if we're in binary mode or if we're using an OS or file

  // system where there is no distinction between text and binary mode.

  bool _M_in_binary_mode() const {

#if defined (_STLP_UNIX) || defined (_STLP_MAC)  || defined(__BEOS__) || defined (__amigaos__) || defined (__SYMBIAN32__)

    return true;

#elif defined (_STLP_WIN32) || defined (_STLP_WIN16) || defined (_STLP_DOS) || defined (_STLP_VM) || defined (__EMX__) || defined(N_PLAT_NLM)

    return (_M_openmode & ios_base::binary) != 0;

#else

#  error "Port!"

#endif

  }

  static void _S_initialize();

protected:                      // Static data members.

# if !defined(__SYMBIAN32__WSD__)

  static size_t _M_page_size;

#endif //__SYMBIAN32__

protected:                      // Data members.

  _STLP_fd _M_file_id;

#if defined (_STLP_USE_STDIO_IO)

  // for stdio, the whole FILE* is being kept here

  FILE* _M_file;

#endif

#if defined (_STLP_USE_WIN32_IO)

  _STLP_fd _M_view_id;

#endif

  ios_base::openmode _M_openmode     ;

  unsigned char      _M_is_open      ;

  unsigned char      _M_should_close ;

  unsigned char      _M_regular_file ;

public :

#if defined(__SYMBIAN32__) && defined (__EPOC32__)

  /* On Symbian,we can't make this inline.   It violates one address rule */ 	

  _STLP_DECLSPEC static size_t __page_size();

#else

  static size_t  _STLP_CALL __page_size() { return _M_page_size; }

#endif  

  int  __o_mode() const { return (int)_M_openmode; }

  bool __is_open()      const { return (_M_is_open !=0 ); }

  bool __should_close() const { return (_M_should_close != 0); }

  bool __regular_file() const { return (_M_regular_file != 0); }

  _STLP_fd __get_fd() const { return _M_file_id; }

};

//----------------------------------------------------------------------

// Class basic_filebuf<>.

// Forward declaration of two helper classes.

template <class _Traits> class _Noconv_input;

_STLP_TEMPLATE_NULL

class _Noconv_input<char_traits<char> >;

template <class _Traits> class _Noconv_output;

_STLP_TEMPLATE_NULL

class _Noconv_output< char_traits<char> >;

// There is a specialized version of underflow, for basic_filebuf<char>,

// in fstream.cxx.

template <class _CharT, class _Traits>

class _Underflow;

_STLP_TEMPLATE_NULL class _Underflow< char, char_traits<char> >;

template <class _CharT, class _Traits>

class basic_filebuf : public basic_streambuf<_CharT, _Traits> {

public:                         // Types.

  typedef _CharT                     char_type;

  typedef typename _Traits::int_type int_type;

  typedef typename _Traits::pos_type pos_type;

  typedef typename _Traits::off_type off_type;

  typedef _Traits                    traits_type;

  typedef typename _Traits::state_type _State_type;

  typedef basic_streambuf<_CharT, _Traits> _Base;

  typedef basic_filebuf<_CharT, _Traits> _Self;

public:                         // Constructors, destructor.

  basic_filebuf();

  ~basic_filebuf();

public:                         // Opening and closing files.

  bool is_open() const { return _M_base.__is_open(); }

  _Self* open(const char* __s, ios_base::openmode __m) {

    return _M_base._M_open(__s, __m) ? this : 0;

  }

#if !defined (_STLP_NO_EXTENSIONS)

  // These two version of open() and file descriptor getter are extensions.

  _Self* open(const char* __s, ios_base::openmode __m,

              long __protection) {

    return _M_base._M_open(__s, __m, __protection) ? this : 0;

  }

  _STLP_fd fd() const { return _M_base.__get_fd(); }

  _Self* open(int __id, ios_base::openmode _Init_mode = ios_base::__default_mode) {

    return this->_M_open(__id, _Init_mode);

  }

#  if defined (_STLP_USE_WIN32_IO)

  _Self* open(_STLP_fd __id, ios_base::openmode _Init_mode = ios_base::__default_mode) {

    return _M_base._M_open(__id, _Init_mode) ? this : 0;

  }

#  endif /* _STLP_USE_WIN32_IO */

#endif

  _Self* _M_open(int __id, ios_base::openmode _Init_mode = ios_base::__default_mode) {

    return _M_base._M_open(__id, _Init_mode) ? this : 0;

  }

  _Self* close();

protected:                      // Virtual functions from basic_streambuf.

  virtual streamsize showmanyc();

  virtual int_type underflow();

  virtual int_type pbackfail(int_type = traits_type::eof());

  virtual int_type overflow(int_type = traits_type::eof());

  virtual basic_streambuf<_CharT, _Traits>* setbuf(char_type*, streamsize);

  virtual pos_type seekoff(off_type, ios_base::seekdir,

                           ios_base::openmode = ios_base::in | ios_base::out);

  virtual pos_type seekpos(pos_type,

                           ios_base::openmode = ios_base::in | ios_base::out);

  virtual int sync();

  virtual void imbue(const locale&);

private:                        // Helper functions.

  // Precondition: we are currently in putback input mode.  Effect:

  // switches back to ordinary input mode.

  void _M_exit_putback_mode() {

    this->setg(_M_saved_eback, _M_saved_gptr, _M_saved_egptr);

    _M_in_putback_mode = false;

  }

  bool _M_switch_to_input_mode();

  void _M_exit_input_mode();

  bool _M_switch_to_output_mode();

  int_type _M_input_error();

  int_type _M_underflow_aux();

  //  friend class _Noconv_input<_Traits>;

  //  friend class _Noconv_output<_Traits>;

  friend class _Underflow<_CharT, _Traits>;

  int_type _M_output_error();

  bool _M_unshift();

  bool _M_allocate_buffers(_CharT* __buf, streamsize __n);

  bool _M_allocate_buffers();

  void _M_deallocate_buffers();

  pos_type _M_seek_return(off_type __off, _State_type __state) {

    if (__off != -1) {

      if (_M_in_input_mode)

        _M_exit_input_mode();

      _M_in_input_mode = false;

      _M_in_output_mode = false;

      _M_in_putback_mode = false;

      _M_in_error_mode = false;

      this->setg(0, 0, 0);

      this->setp(0, 0);

    }

    pos_type __result(__off);

    __result.state(__state);

    return __result;

  }

  bool _M_seek_init(bool __do_unshift);

  void _M_setup_codecvt(const locale&, bool __on_imbue = true);

private:                        // Data members used in all modes.

  _Filebuf_base _M_base;

private:                        // Locale-related information.

  unsigned char _M_constant_width;

  unsigned char _M_always_noconv;

  // private:                        // Mode flags.

  unsigned char _M_int_buf_dynamic;  // True if internal buffer is heap allocated,

  // false if it was supplied by the user.

  unsigned char _M_in_input_mode;

  unsigned char _M_in_output_mode;

  unsigned char _M_in_error_mode;

  unsigned char _M_in_putback_mode;

  // Internal buffer: characters seen by the filebuf's clients.

  _CharT* _M_int_buf;

  _CharT* _M_int_buf_EOS;

  // External buffer: characters corresponding to the external file.

  char* _M_ext_buf;

  char* _M_ext_buf_EOS;

  // The range [_M_ext_buf, _M_ext_buf_converted) contains the external

  // characters corresponding to the sequence in the internal buffer.  The

  // range [_M_ext_buf_converted, _M_ext_buf_end) contains characters that

  // have been read into the external buffer but have not been converted

  // to an internal sequence.

  char* _M_ext_buf_converted;

  char* _M_ext_buf_end;

  // State corresponding to beginning of internal buffer.

  _State_type _M_state;

private:                        // Data members used only in input mode.

  // Similar to _M_state except that it corresponds to

  // the end of the internal buffer instead of the beginning.

  _State_type _M_end_state;

  // This is a null pointer unless we are in mmap input mode.

  void*     _M_mmap_base;

  streamoff _M_mmap_len;

private:                        // Data members used only in putback mode.

  _CharT* _M_saved_eback;

  _CharT* _M_saved_gptr;

  _CharT* _M_saved_egptr;

  typedef codecvt<_CharT, char, _State_type> _Codecvt;

  const _Codecvt* _M_codecvt;

  int _M_width;                 // Width of the encoding (if constant), else 1

  int _M_max_width;             // Largest possible width of single character.

  enum { _S_pback_buf_size = 8 };

  _CharT _M_pback_buf[_S_pback_buf_size];

  // for _Noconv_output

public:

  bool _M_write(char* __buf,  ptrdiff_t __n) {return _M_base._M_write(__buf, __n); }

public:

  int_type

  _M_do_noconv_input() {

    _M_ext_buf_converted = _M_ext_buf_end;

    /* this-> */ _Base::setg((char_type*)_M_ext_buf, (char_type*)_M_ext_buf, (char_type*)_M_ext_buf_end);

    return traits_type::to_int_type(*_M_ext_buf);

  }

};

#if defined (_STLP_USE_TEMPLATE_EXPORT)

_STLP_EXPORT_TEMPLATE_CLASS basic_filebuf<char, char_traits<char> >;

#  if ! defined (_STLP_NO_WCHAR_T)

_STLP_EXPORT_TEMPLATE_CLASS basic_filebuf<wchar_t, char_traits<wchar_t> >;

#  endif

#endif /* _STLP_USE_TEMPLATE_EXPORT */

// public:

// helper class.

template <class _CharT>

struct _Filebuf_Tmp_Buf {

  _CharT* _M_ptr;

  _Filebuf_Tmp_Buf(ptrdiff_t __n) : _M_ptr(0) { _M_ptr = new _CharT[__n]; }

  ~_Filebuf_Tmp_Buf() { delete[] _M_ptr; }

};

//

// This class had to be designed very carefully to work

// with Visual C++.

//

template <class _Traits>

class _Noconv_output {

public:

  typedef typename _Traits::char_type char_type;

  static bool  _STLP_CALL _M_doit(basic_filebuf<char_type, _Traits >*,

                                  char_type*, char_type*)

  { return false; }

};

_STLP_TEMPLATE_NULL

class _STLP_CLASS_DECLSPEC _Noconv_output< char_traits<char> > {

public:

  static bool  _STLP_CALL

  _M_doit(basic_filebuf<char, char_traits<char> >* __buf,

          char* __first, char* __last) {

    ptrdiff_t __n = __last - __first;

    return (__buf->_M_write(__first, __n));

  }

};

//----------------------------------------------------------------------

// basic_filebuf<> helper functions.

//----------------------------------------

// Helper functions for switching between modes.

//

// This class had to be designed very carefully to work

// with Visual C++.

//

template <class _Traits>

class _Noconv_input {

public:

  typedef typename _Traits::int_type int_type;

  typedef typename _Traits::char_type char_type;

  static inline int_type _STLP_CALL

  _M_doit(basic_filebuf<char_type, _Traits>*)

  { return _Traits::eof(); }

};

_STLP_TEMPLATE_NULL

class _Noconv_input<char_traits<char> > {

public:

  static inline int _STLP_CALL

  _M_doit(basic_filebuf<char, char_traits<char> >* __buf) {

    return __buf->_M_do_noconv_input();

  }

};

// underflow() may be called for one of two reasons.  (1) We've

// been going through the special putback buffer, and we need to move back

// to the regular internal buffer.  (2) We've exhausted the internal buffer,

// and we need to replentish it.

template <class _CharT, class _Traits>

class _Underflow {

public:

  typedef typename _Traits::int_type int_type;

  typedef _Traits                    traits_type;

  static int_type _STLP_CALL _M_doit(basic_filebuf<_CharT, _Traits>* __this);

};

// Specialization of underflow: if the character type is char, maybe

// we can use mmap instead of read.

_STLP_TEMPLATE_NULL

class _STLP_CLASS_DECLSPEC _Underflow< char, char_traits<char> > {

public:

  typedef char_traits<char>::int_type int_type;

  typedef char_traits<char> traits_type;

  _STLP_DECLSPEC static  int _STLP_CALL _M_doit(basic_filebuf<char, traits_type >* __this);

};

// There is a specialized version of underflow, for basic_filebuf<char>,

// in fstream.cxx.

template <class _CharT, class _Traits>

_STLP_TYPENAME_ON_RETURN_TYPE _Underflow<_CharT, _Traits>::int_type // _STLP_CALL

 _Underflow<_CharT, _Traits>::_M_doit(basic_filebuf<_CharT, _Traits>* __this) {

  if (!__this->_M_in_input_mode) {

    if (!__this->_M_switch_to_input_mode())

      return traits_type::eof();

  }

  else if (__this->_M_in_putback_mode) {

    __this->_M_exit_putback_mode();

    if (__this->gptr() != __this->egptr()) {

      int_type __c = traits_type::to_int_type(*__this->gptr());

      return __c;

    }

  }

  return __this->_M_underflow_aux();

}

#if defined (_STLP_USE_TEMPLATE_EXPORT) && !defined (_STLP_NO_WCHAR_T)

_STLP_EXPORT_TEMPLATE_CLASS _Underflow<wchar_t, char_traits<wchar_t> >;

#endif

//----------------------------------------------------------------------

// Class basic_ifstream<>

template <class _CharT, class _Traits>

class basic_ifstream : public basic_istream<_CharT, _Traits> {

public:                         // Types

  typedef _CharT                     char_type;

  typedef typename _Traits::int_type int_type;

  typedef typename _Traits::pos_type pos_type;

  typedef typename _Traits::off_type off_type;

  typedef _Traits                    traits_type;

  typedef basic_ios<_CharT, _Traits>                _Basic_ios;

  typedef basic_istream<_CharT, _Traits>            _Base;

  typedef basic_filebuf<_CharT, _Traits>            _Buf;

public:                         // Constructors, destructor.

  basic_ifstream() :

    basic_ios<_CharT, _Traits>(),  basic_istream<_CharT, _Traits>(0), _M_buf() {

      this->init(&_M_buf);

  }

  explicit basic_ifstream(const char* __s, ios_base::openmode __mod = ios_base::in) :

    basic_ios<_CharT, _Traits>(),  basic_istream<_CharT, _Traits>(0),

    _M_buf() {

      this->init(&_M_buf);

      if (!_M_buf.open(__s, __mod | ios_base::in))

        this->setstate(ios_base::failbit);

  }

#if !defined (_STLP_NO_EXTENSIONS)

  explicit basic_ifstream(int __id, ios_base::openmode __mod = ios_base::in) :