windows-nt/Source/XPSP1/NT/base/crts/libw32/include/fstream

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2020-09-26 03:20:57 -05:00
// fstream standard header
#pragma once
#ifndef _FSTREAM_
#define _FSTREAM_
#include <istream>
#pragma pack(push,8)
#pragma warning(push,3)
#pragma warning(disable: 4127)
_STD_BEGIN
extern _CRTIMP2 _Filet *__cdecl _Fiopen(const char *, ios_base::openmode);
// TEMPLATE FUNCTION _Fgetc
template<class _Elem> inline
bool _Fgetc(_Elem& _Ch, _Filet *_File)
{ // get an element from a C stream
return (fread(&_Ch, sizeof (_Elem), 1, _File) == 1);
}
template<> inline bool _Fgetc(char& _Byte, _Filet *_File)
{ // get a char element from a C stream
int _Meta;
if ((_Meta = fgetc(_File)) == EOF)
return (false);
else
{ // got one, convert to char
_Byte = (char)_Meta;
return (true);
}
}
template<> inline bool _Fgetc(wchar_t& _Wchar, _Filet *_File)
{ // get a wchar_t element from a C stream
wint_t _Meta;
if ((_Meta = fgetwc(_File)) == WEOF)
return (false);
else
{ // got one, convert to wchar_t
_Wchar = (wchar_t)_Meta;
return (true);
}
}
// TEMPLATE FUNCTION _Fputc
template<class _Elem> inline
bool _Fputc(_Elem _Ch, _Filet *_File)
{ // put an element to a C stream
return (fwrite(&_Ch, sizeof (_Elem), 1, _File) == 1);
}
template<> inline bool _Fputc(char _Byte, _Filet *_File)
{ // put a char element to a C stream
return (fputc(_Byte, _File) != EOF);
}
template<> inline bool _Fputc(wchar_t _Wchar, _Filet *_File)
{ // put a wchar_t element to a C stream
return (fputwc(_Wchar, _File) != WEOF);
}
// TEMPLATE FUNCTION _Ungetc
template<class _Elem> inline
bool _Ungetc(const _Elem& _Ch, _Filet *_File)
{ // put back an arbitrary element to a C stream (always fail)
return (false);
}
template<> inline bool _Ungetc(const char& _Byte, _Filet *_File)
{ // put back a char element to a C stream
return (ungetc((unsigned char)_Byte, _File) != EOF);
}
template<> inline bool _Ungetc(const signed char& _Byte, _Filet *_File)
{ // put back a signed char element to a C stream
return (ungetc((unsigned char)_Byte, _File) != EOF);
}
template<> inline bool _Ungetc(const unsigned char& _Byte, _Filet *_File)
{ // put back an unsigned char element to a C stream
return (ungetc(_Byte, _File) != EOF);
}
template<> inline bool _Ungetc(const wchar_t& _Wchar, _Filet *_File)
{ // put back a wchar_t element to a C stream
return (ungetwc(_Wchar, _File) != WEOF);
}
// TEMPLATE CLASS basic_filebuf
template<class _Elem,
class _Traits>
class basic_filebuf
: public basic_streambuf<_Elem, _Traits>
{ // stream buffer associated with a C stream
public:
typedef basic_filebuf<_Elem, _Traits> _Myt;
typedef basic_streambuf<_Elem, _Traits> _Mysb;
typedef codecvt<_Elem, char, typename _Traits::state_type> _Cvt;
virtual ~basic_filebuf()
{ // destroy the object
if (_Closef)
close();
_DELETE_CRT(_Mystr);
}
basic_filebuf(_Filet *_File = 0)
: _Mysb(), _Mystr(0), _Loc()
{ // construct from pointer to C stream
_Init(_File, _Newfl);
}
typedef typename _Traits::int_type int_type;
typedef typename _Traits::pos_type pos_type;
typedef typename _Traits::off_type off_type;
basic_filebuf(_Uninitialized)
: _Mysb(_Noinit), _Loc(_Noinit)
{ // construct uninitialized
}
enum _Initfl
{ // reasons for a call to _Init
_Newfl, _Openfl, _Closefl};
bool is_open() const
{ // test if C stream has been opened
return (_Myfile != 0);
}
_Myt *open(const char *_Filename, ios_base::openmode _Mode)
{ // open a C stream with specified mode
_Filet *_File;
if (_Myfile != 0 || (_File = _Fiopen(_Filename, _Mode)) == 0)
return (0); // open failed
_Init(_File, _Openfl);
_Initcvt((_Cvt *)&_USE(_Mysb::getloc(), _Cvt));
return (this); // open succeeded
}
_Myt *open(const char *_Filename, ios_base::open_mode _Mode)
{ // open a C stream with specified mode (old style)
return (open(_Filename, (ios_base::openmode)_Mode));
}
_Myt *close()
{ // close the C stream
if (_Myfile != 0 && _Endwrite() && fclose(_Myfile) == 0)
{ // close succeeded, tidy up
_Init(0, _Closefl);
return (this);
}
else
return (0);
}
protected:
virtual int_type overflow(int_type _Meta = _Traits::eof())
{ // put an element to stream
if (_Traits::eq_int_type(_Traits::eof(), _Meta))
return (_Traits::not_eof(_Meta)); // EOF, return success code
else if (_Mysb::pptr() != 0
&& _Mysb::pptr() < _Mysb::epptr())
{ // room in buffer, store it
*_Mysb::_Pninc() = _Traits::to_char_type(_Meta);
return (_Meta);
}
else if (_Myfile == 0)
return (_Traits::eof()); // no open C stream, fail
else if (_Pcvt == 0)
return (_Fputc(_Traits::to_char_type(_Meta), _Myfile)
? _Meta : _Traits::eof()); // no codecvt facet, put as is
else
{ // put using codecvt facet
const int _STRING_INC = 8;
const _Elem _Ch = _Traits::to_char_type(_Meta);
const _Elem *_Source;
char *_Dest;
_Mystr->erase();
string _Str(_STRING_INC, '\0');
for (; ; )
switch (_Pcvt->out(_State,
&_Ch, &_Ch + 1, _Source,
&*_Str.begin(), &*_Str.end(), _Dest))
{ // test result of converting one element
case codecvt_base::partial:
case codecvt_base::ok:
{ // converted something, try to put it out
size_t _Count = _Dest - &*_Str.begin();
if (0 < _Count && _Count !=
fwrite(&*_Str.begin(), 1, _Count, _Myfile))
return (_Traits::eof()); // write failed
_Wrotesome = true; // write succeeded
if (_Source != &_Ch)
return (_Meta); // converted whole element
if (_Count == 0)
_Str.append(_STRING_INC, '\0'); // try some more
break;
}
case codecvt_base::noconv:
return (_Fputc(_Ch, _Myfile) ? _Meta
: _Traits::eof()); // no conversion, put as is
default:
return (_Traits::eof()); // conversion failed
}
}
}
virtual int_type pbackfail(int_type _Meta = _Traits::eof())
{ // put an element back to stream
if (_Mysb::gptr() != 0
&& _Mysb::eback() < _Mysb::gptr()
&& (_Traits::eq_int_type(_Traits::eof(), _Meta)
|| _Traits::eq_int_type(_Traits::to_int_type(_Mysb::gptr()[-1]),
_Meta)))
{ // just back up position
_Mysb::_Gndec();
return (_Traits::not_eof(_Meta));
}
else if (_Myfile == 0 || _Traits::eq_int_type(_Traits::eof(), _Meta))
return (_Traits::eof()); // no open C stream or EOF, fail
else if (_Pcvt == 0 && _Ungetc(_Traits::to_char_type(_Meta), _Myfile))
return (_Meta); // no facet and unget succeeded, return
else
{ // putback to _Mychar
_Mychar = _Traits::to_char_type(_Meta);
_Mysb::setg(&_Mychar, &_Mychar, &_Mychar + 1);
return (_Meta);
}
}
virtual int_type underflow()
{ // get an element from stream, but don't point past it
int_type _Meta;
if (_Mysb::gptr() != 0
&& _Mysb::gptr() < _Mysb::egptr())
return (_Traits::to_int_type(*_Mysb::gptr())); // return buffered
else if (_Traits::eq_int_type(_Traits::eof(), _Meta = uflow()))
return (_Meta); // uflow failed, return EOF
else
{ // get a char, don't point past it
pbackfail(_Meta);
return (_Meta);
}
}
virtual int_type uflow()
{ // get an element from stream, point past it
if (_Mysb::gptr() != 0
&& _Mysb::gptr() < _Mysb::egptr())
return (_Traits::to_int_type(
*_Mysb::_Gninc())); // return buffered
else if (_Myfile == 0)
return (_Traits::eof()); // no open C stream, fail
else if (_Pcvt == 0)
{ // no codecvt facet, just get it
_Elem _Ch = 0;
return (_Fgetc(_Ch, _Myfile) ? _Traits::to_int_type(_Ch)
: _Traits::eof());
}
else
for (_State0 = _State, _Mystr->erase(); ; )
{ // get using codecvt facet
_Elem _Ch, *_Dest;
const char *_Source;
int _Meta = fgetc(_Myfile);
if (_Meta == EOF)
return (_Traits::eof()); // partial char?
_Mystr->append(1, (char)_Meta); // append byte and convert
_State = _State0;
switch (_Pcvt->in(_State,
&*_Mystr->begin(), &*_Mystr->end(), _Source,
&_Ch, &_Ch + 1, _Dest))
{ // test result of converting one element
case codecvt_base::partial:
break; // partial, not done yet
case codecvt_base::noconv:
if (_Mystr->size() < sizeof (_Elem))
break; // no conversion, but need more chars
memcpy(&_Ch, &*_Mystr->begin(),
sizeof (_Elem)); // copy raw bytes to element
case codecvt_base::ok: // can fall through
return (_Traits::to_int_type(_Ch)); // return result
default:
return (_Traits::eof()); // conversion failed
}
}
}
virtual pos_type seekoff(off_type _Off, ios_base::seekdir _Way,
ios_base::openmode =
(ios_base::openmode)(ios_base::in | ios_base::out))
{ // change position by _Off
fpos_t _Fileposition;
if (_Mysb::gptr() != &_Mychar
|| _Mysb::egptr() <= _Mysb::gptr()
|| _Way != ios_base::cur)
; // don't have to worry about putback character
else if (_Pcvt == 0)
_Off -= (off_type)sizeof (_Elem); // back up over _Elem bytes
else
{ // back up over converted bytes
_Off -= (off_type)_Mystr->size();
_Mystr->erase();
_State = _State0;
}
if (_Myfile == 0 || !_Endwrite()
|| (_Off != 0 || _Way != ios_base::cur)
&& fseek(_Myfile, (long)_Off, _Way) != 0
|| fgetpos(_Myfile, &_Fileposition) != 0)
return (pos_type(_BADOFF)); // report failure
if (_Mysb::gptr() == &_Mychar)
_Mysb::setg(&_Mychar, &_Mychar, &_Mychar); // discard putback
return (pos_type(_State, _Fileposition)); // return new position
}
virtual pos_type seekpos(pos_type _Pos,
ios_base::openmode =
(ios_base::openmode)(ios_base::in | ios_base::out))
{ // change position to _Pos
fpos_t _Fileposition = _Pos.seekpos();
off_type _Off = (off_type)_Pos - _FPOSOFF(_Fileposition);
if (_Myfile == 0 || !_Endwrite()
|| fsetpos(_Myfile, &_Fileposition) != 0
|| _Off != 0 && fseek(_Myfile, (long)_Off, SEEK_CUR) != 0
|| fgetpos(_Myfile, &_Fileposition) != 0)
return (pos_type(_BADOFF)); // report failure
if (_Mystr != 0)
_State = _Pos.state(), _Mystr->erase(); // restore state
if (_Mysb::gptr() == &_Mychar)
_Mysb::setg(&_Mychar, &_Mychar, &_Mychar); // discard putback
return (pos_type(_State, _Fileposition)); // return new position
}
virtual _Mysb *setbuf(_Elem *_Buffer, streamsize _Count)
{ // offer _Buffer to C stream
return (_Myfile == 0 || setvbuf(_Myfile, (char *)_Buffer,
_Buffer == 0 && _Count == 0 ? _IONBF : _IOFBF,
_Count * sizeof (_Elem)) != 0 ? 0 : this);
}
virtual int sync()
{ // synchronize C stream with external file
return (_Myfile == 0
|| _Traits::eq_int_type(_Traits::eof(), overflow())
|| 0 <= fflush(_Myfile) ? 0 : -1);
}
virtual void imbue(const locale& _Loc)
{ // set locale to argument (capture nontrivial codecvt facet)
_Initcvt((_Cvt *)&_USE(_Loc, _Cvt));
}
void _Init(_Filet *_File, _Initfl _Which)
{ // initialize to C stream _File after {new, open, close}
static typename _Traits::state_type _Stinit; // initial state
_Closef = _Which == _Openfl;
_Wrotesome = false;
_Mysb::_Init(); // initialize stream buffer base object
#ifndef _IORCNT
#define _IORCNT _IOCNT /* read and write counts are the same */
#define _IOWCNT _IOCNT
#endif
if (_File != 0 && sizeof (_Elem) == 1)
{ // point inside C stream with [first, first + count) buffer
_Elem **_Pb = (_Elem **)&_File->_IOBASE;
_Elem **_Pn = (_Elem **)&_File->_IOPTR;
int *_Nr = (int *)&_File->_IORCNT;
int *_Nw = (int *)&_File->_IOWCNT;
_Mysb::_Init(_Pb, _Pn, _Nr, _Pb, _Pn, _Nw);
}
_Myfile = _File;
_State = _Stinit;
_State0 = _Stinit;
_Pcvt = 0; // pointer to codecvt facet
}
bool _Endwrite()
{ // put shift to initial conversion state, as needed
if (_Pcvt == 0 || !_Wrotesome)
return (true);
else
{ // may have to put
const int _STRING_INC = 8;
char *_Dest;
overflow();
string _Str(_STRING_INC, '\0');
for (; ; )
switch (_Pcvt->unshift(_State,
&*_Str.begin(), &*_Str.end(), _Dest))
{ // test result of homing conversion
case codecvt_base::ok:
_Wrotesome = false; // homed successfully
case codecvt_base::partial: // can fall through
{ // put any generated bytes
size_t _Count = _Dest - &*_Str.begin();
if (0 < _Count && _Count !=
fwrite(&*_Str.begin(), _Count, 1, _Myfile))
return (false); // write failed
if (!_Wrotesome)
return (true);
_Str.append(_STRING_INC, '\0'); // try some more
break;
}
case codecvt_base::noconv:
return (true); // nothing to do
default:
return (false); // conversion failed
}
}
}
void _Initcvt(_Cvt *_Newpcvt)
{ // initialize codecvt pointer
if (_Newpcvt->always_noconv())
_Pcvt = 0; // nothing to do
else
{ // set up for nontrivial codecvt facet
_Pcvt = _Newpcvt;
_Loc = _ADDFAC(_Loc, _Pcvt); // to keep facet alive
_Mysb::_Init(); // reset any buffering
if (_Mystr == 0)
_Mystr = _NEW_CRT _STRING_CRT; // buy conversion buffer
}
}
private:
_Cvt *_Pcvt; // pointer to codecvt facet (may be null)
typename _Traits::state_type _State0; // rollback for bad conversion
_Elem _Mychar; // putback character, when _Ungetc fails
_STRING_CRT *_Mystr; // string to hold partial conversion byte sequences
bool _Wrotesome; // true if homing sequence may be needed
typename _Traits::state_type _State; // current conversion state
bool _Closef; // true if C stream must be closed
locale _Loc; // locale object to hold codecvt facet
_Filet *_Myfile; // pointer to C stream
};
#ifdef _DLL_CPPLIB
template class _CRTIMP2 basic_filebuf<char,
char_traits<char> >;
template class _CRTIMP2 basic_filebuf<wchar_t,
char_traits<wchar_t> >;
#endif // _DLL_CPPLIB
// TEMPLATE CLASS basic_ifstream
template<class _Elem,
class _Traits>
class basic_ifstream
: public basic_istream<_Elem, _Traits>
{ // input stream associated with a C stream
public:
typedef basic_ifstream<_Elem, _Traits> _Myt;
typedef basic_filebuf<_Elem, _Traits> _Myfb;
typedef basic_ios<_Elem, _Traits> _Myios;
basic_ifstream()
: basic_istream<_Elem, _Traits>(&_Filebuffer)
{ // construct unopened
}
explicit basic_ifstream(const char *_Filename,
ios_base::openmode _Mode = ios_base::in)
: basic_istream<_Elem, _Traits>(&_Filebuffer)
{ // construct with named file and specified mode
if (_Filebuffer.open(_Filename, _Mode | ios_base::in) == 0)
_Myios::setstate(ios_base::failbit);
}
virtual ~basic_ifstream()
{ // destroy the object
}
_Myfb *rdbuf() const
{ // return pointer to file buffer
return ((_Myfb *)&_Filebuffer);
}
bool is_open() const
{ // test if C stream has been opened
return (_Filebuffer.is_open());
}
void open(const char *_Filename,
ios_base::openmode _Mode = ios_base::in)
{ // open a C stream with specified mode
if (_Filebuffer.open(_Filename, _Mode | ios_base::in) == 0)
_Myios::setstate(ios_base::failbit);
}
void open(const char *_Filename, ios_base::open_mode _Mode)
{ // open named file with specified mode (old style)
open(_Filename, (ios_base::openmode)_Mode);
}
void close()
{ // close the C stream
if (_Filebuffer.close() == 0)
_Myios::setstate(ios_base::failbit);
}
private:
_Myfb _Filebuffer; // the file buffer
};
#ifdef _DLL_CPPLIB
template class _CRTIMP2 basic_ifstream<char,
char_traits<char> >;
template class _CRTIMP2 basic_ifstream<wchar_t,
char_traits<wchar_t> >;
#endif // _DLL_CPPLIB
// TEMPLATE CLASS basic_ofstream
template<class _Elem,
class _Traits>
class basic_ofstream
: public basic_ostream<_Elem, _Traits>
{ // output stream associated with a C stream
public:
typedef basic_ofstream<_Elem, _Traits> _Myt;
typedef basic_filebuf<_Elem, _Traits> _Myfb;
typedef basic_ios<_Elem, _Traits> _Myios;
basic_ofstream()
: basic_ostream<_Elem, _Traits>(&_Filebuffer)
{ // construct unopened
}
explicit basic_ofstream(const char *_Filename,
ios_base::openmode _Mode = ios_base::out)
: basic_ostream<_Elem, _Traits>(&_Filebuffer)
{ // construct with named file and specified mode
if (_Filebuffer.open(_Filename, _Mode | ios_base::out) == 0)
_Myios::setstate(ios_base::failbit);
}
virtual ~basic_ofstream()
{ // destroy the object
}
_Myfb *rdbuf() const
{ // return pointer to file buffer
return ((_Myfb *)&_Filebuffer);
}
bool is_open() const
{ // test if C stream has been opened
return (_Filebuffer.is_open());
}
void open(const char *_Filename,
ios_base::openmode _Mode = ios_base::out)
{ // open a C stream with specified mode
if (_Filebuffer.open(_Filename, _Mode | ios_base::out) == 0)
_Myios::setstate(ios_base::failbit);
}
void open(const char *_Filename, ios_base::open_mode _Mode)
{ // open a C stream with specified mode (old style)
open(_Filename, (ios_base::openmode)_Mode);
}
void close()
{ // close the C stream
if (_Filebuffer.close() == 0)
_Myios::setstate(ios_base::failbit);
}
private:
_Myfb _Filebuffer; // the file buffer
};
#ifdef _DLL_CPPLIB
template class _CRTIMP2 basic_ofstream<char,
char_traits<char> >;
template class _CRTIMP2 basic_ofstream<wchar_t,
char_traits<wchar_t> >;
#endif // _DLL_CPPLIB
// TEMPLATE CLASS basic_fstream
template<class _Elem,
class _Traits>
class basic_fstream
: public basic_iostream<_Elem, _Traits>
{ // input/output stream associated with a C stream
public:
typedef basic_ios<_Elem, _Traits> _Myios;
typedef _Elem char_type;
typedef _Traits traits_type;
typedef typename _Traits::int_type int_type;
typedef typename _Traits::pos_type pos_type;
typedef typename _Traits::off_type off_type;
basic_fstream()
: basic_iostream<_Elem, _Traits>(&_Filebuffer)
{ // construct unopened
}
explicit basic_fstream(const char *_Filename,
ios_base::openmode _Mode = ios_base::in | ios_base::out)
: basic_iostream<_Elem, _Traits>(&_Filebuffer)
{ // construct with named file and specified mode
if (_Filebuffer.open(_Filename, _Mode) == 0)
_Myios::setstate(ios_base::failbit);
}
virtual ~basic_fstream()
{ // destroy the object
}
basic_filebuf<_Elem, _Traits> *rdbuf() const
{ // return pointer to file buffer
return ((basic_filebuf<_Elem, _Traits> *)&_Filebuffer);
}
bool is_open() const
{ // test if C stream has been opened
return (_Filebuffer.is_open());
}
void open(const char *_Filename,
ios_base::openmode _Mode = ios_base::in | ios_base::out)
{ // open a C stream with specified mode
if (_Filebuffer.open(_Filename, _Mode) == 0)
_Myios::setstate(ios_base::failbit);
}
void open(const char *_Filename, ios_base::open_mode _Mode)
{ // open a C stream with specified mode (old style)
open(_Filename, (ios_base::openmode)_Mode);
}
void close()
{ // close the C stream
if (_Filebuffer.close() == 0)
_Myios::setstate(ios_base::failbit);
}
private:
basic_filebuf<_Elem, _Traits> _Filebuffer; // the file buffer
};
#ifdef _DLL_CPPLIB
template class _CRTIMP2 basic_fstream<char,
char_traits<char> >;
template class _CRTIMP2 basic_fstream<wchar_t,
char_traits<wchar_t> >;
#endif // _DLL_CPPLIB
_STD_END
#pragma warning(default: 4127)
#pragma warning(pop)
#pragma pack(pop)
#endif /* _FSTREAM_ */
/*
* Copyright (c) 1992-2001 by P.J. Plauger. ALL RIGHTS RESERVED.
* Consult your license regarding permissions and restrictions.
V3.10:0009 */