📄 fstream
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// [documentation is inherited]
virtual streamsize
xsputn(const char_type* __s, streamsize __n);
// Flushes output buffer, then writes unshift sequence.
/**
* @if maint
* @doctodo
* @endif
*/
bool
_M_terminate_output();
/**
* @if maint
* This function sets the pointers of the internal buffer, both get
* and put areas. Typically:
*
* __off == egptr() - eback() upon underflow/uflow ('read' mode);
* __off == 0 upon overflow ('write' mode);
* __off == -1 upon open, setbuf, seekoff/pos ('uncommitted' mode).
*
* NB: epptr() - pbase() == _M_buf_size - 1, since _M_buf_size
* reflects the actual allocated memory and the last cell is reserved
* for the overflow char of a full put area.
* @endif
*/
void
_M_set_buffer(streamsize __off)
{
const bool __testin = this->_M_mode & ios_base::in;
const bool __testout = this->_M_mode & ios_base::out;
if (__testin && __off > 0)
this->setg(this->_M_buf, this->_M_buf, this->_M_buf + __off);
else
this->setg(this->_M_buf, this->_M_buf, this->_M_buf);
if (__testout && __off == 0 && this->_M_buf_size > 1 )
this->setp(this->_M_buf, this->_M_buf + this->_M_buf_size - 1);
else
this->setp(NULL, NULL);
}
};
// [27.8.1.5] Template class basic_ifstream
/**
* @brief Controlling input for files.
*
* This class supports reading from named files, using the inherited
* functions from std::basic_istream. To control the associated
* sequence, an instance of std::basic_filebuf is used, which this page
* refers to as @c sb.
*/
template<typename _CharT, typename _Traits>
class basic_ifstream : public basic_istream<_CharT, _Traits>
{
public:
// Types:
typedef _CharT char_type;
typedef _Traits traits_type;
typedef typename traits_type::int_type int_type;
typedef typename traits_type::pos_type pos_type;
typedef typename traits_type::off_type off_type;
// Non-standard types:
typedef basic_filebuf<char_type, traits_type> __filebuf_type;
typedef basic_istream<char_type, traits_type> __istream_type;
private:
/**
* @if maint
* @doctodo
* @endif
*/
__filebuf_type _M_filebuf;
public:
// Constructors/Destructors:
/**
* @brief Default constructor.
*
* Initializes @c sb using its default constructor, and passes
* @c &sb to the base class initializer. Does not open any files
* (you haven't given it a filename to open).
*/
basic_ifstream() : __istream_type(), _M_filebuf()
{ this->init(&_M_filebuf); }
/**
* @brief Create an input file stream.
* @param s Null terminated string specifying the filename.
* @param mode Open file in specified mode (see std::ios_base).
*
* @c ios_base::in is automatically included in @a mode.
*
* Tip: When using std::string to hold the filename, you must use
* .c_str() before passing it to this constructor.
*/
explicit
basic_ifstream(const char* __s, ios_base::openmode __mode = ios_base::in)
: __istream_type(), _M_filebuf()
{
this->init(&_M_filebuf);
this->open(__s, __mode);
}
/**
* @brief The destructor does nothing.
*
* The file is closed by the filebuf object, not the formatting
* stream.
*/
~basic_ifstream()
{ }
// Members:
/**
* @brief Accessing the underlying buffer.
* @return The current basic_filebuf buffer.
*
* This hides both signatures of std::basic_ios::rdbuf().
*/
__filebuf_type*
rdbuf() const
{ return const_cast<__filebuf_type*>(&_M_filebuf); }
/**
* @brief Wrapper to test for an open file.
* @return @c rdbuf()->is_open()
*/
bool
is_open() { return _M_filebuf.is_open(); }
/**
* @brief Opens an external file.
* @param s The name of the file.
* @param mode The open mode flags.
*
* Calls @c std::basic_filebuf::open(s,mode|in). If that function
* fails, @c failbit is set in the stream's error state.
*
* Tip: When using std::string to hold the filename, you must use
* .c_str() before passing it to this constructor.
*/
void
open(const char* __s, ios_base::openmode __mode = ios_base::in)
{
if (!_M_filebuf.open(__s, __mode | ios_base::in))
this->setstate(ios_base::failbit);
}
/**
* @brief Close the file.
*
* Calls @c std::basic_filebuf::close(). If that function
* fails, @c failbit is set in the stream's error state.
*/
void
close()
{
if (!_M_filebuf.close())
this->setstate(ios_base::failbit);
}
};
// [27.8.1.8] Template class basic_ofstream
/**
* @brief Controlling output for files.
*
* This class supports reading from named files, using the inherited
* functions from std::basic_ostream. To control the associated
* sequence, an instance of std::basic_filebuf is used, which this page
* refers to as @c sb.
*/
template<typename _CharT, typename _Traits>
class basic_ofstream : public basic_ostream<_CharT,_Traits>
{
public:
// Types:
typedef _CharT char_type;
typedef _Traits traits_type;
typedef typename traits_type::int_type int_type;
typedef typename traits_type::pos_type pos_type;
typedef typename traits_type::off_type off_type;
// Non-standard types:
typedef basic_filebuf<char_type, traits_type> __filebuf_type;
typedef basic_ostream<char_type, traits_type> __ostream_type;
private:
/**
* @if maint
* @doctodo
* @endif
*/
__filebuf_type _M_filebuf;
public:
// Constructors:
/**
* @brief Default constructor.
*
* Initializes @c sb using its default constructor, and passes
* @c &sb to the base class initializer. Does not open any files
* (you haven't given it a filename to open).
*/
basic_ofstream(): __ostream_type(), _M_filebuf()
{ this->init(&_M_filebuf); }
/**
* @brief Create an output file stream.
* @param s Null terminated string specifying the filename.
* @param mode Open file in specified mode (see std::ios_base).
*
* @c ios_base::out|ios_base::trunc is automatically included in
* @a mode.
*
* Tip: When using std::string to hold the filename, you must use
* .c_str() before passing it to this constructor.
*/
explicit
basic_ofstream(const char* __s,
ios_base::openmode __mode = ios_base::out|ios_base::trunc)
: __ostream_type(), _M_filebuf()
{
this->init(&_M_filebuf);
this->open(__s, __mode);
}
/**
* @brief The destructor does nothing.
*
* The file is closed by the filebuf object, not the formatting
* stream.
*/
~basic_ofstream()
{ }
// Members:
/**
* @brief Accessing the underlying buffer.
* @return The current basic_filebuf buffer.
*
* This hides both signatures of std::basic_ios::rdbuf().
*/
__filebuf_type*
rdbuf() const
{ return const_cast<__filebuf_type*>(&_M_filebuf); }
/**
* @brief Wrapper to test for an open file.
* @return @c rdbuf()->is_open()
*/
bool
is_open() { return _M_filebuf.is_open(); }
/**
* @brief Opens an external file.
* @param s The name of the file.
* @param mode The open mode flags.
*
* Calls @c std::basic_filebuf::open(s,mode|out|trunc). If that
* function fails, @c failbit is set in the stream's error state.
*
* Tip: When using std::string to hold the filename, you must use
* .c_str() before passing it to this constructor.
*/
void
open(const char* __s,
ios_base::openmode __mode = ios_base::out | ios_base::trunc)
{
if (!_M_filebuf.open(__s, __mode | ios_base::out))
this->setstate(ios_base::failbit);
}
/**
* @brief Close the file.
*
* Calls @c std::basic_filebuf::close(). If that function
* fails, @c failbit is set in the stream's error state.
*/
void
close()
{
if (!_M_filebuf.close())
this->setstate(ios_base::failbit);
}
};
// [27.8.1.11] Template class basic_fstream
/**
* @brief Controlling intput and output for files.
*
* This class supports reading from and writing to named files, using
* the inherited functions from std::basic_iostream. To control the
* associated sequence, an instance of std::basic_filebuf is used, which
* this page refers to as @c sb.
*/
template<typename _CharT, typename _Traits>
class basic_fstream : public basic_iostream<_CharT, _Traits>
{
public:
// Types:
typedef _CharT char_type;
typedef _Traits traits_type;
typedef typename traits_type::int_type int_type;
typedef typename traits_type::pos_type pos_type;
typedef typename traits_type::off_type off_type;
// Non-standard types:
typedef basic_filebuf<char_type, traits_type> __filebuf_type;
typedef basic_ios<char_type, traits_type> __ios_type;
typedef basic_iostream<char_type, traits_type> __iostream_type;
private:
/**
* @if maint
* @doctodo
* @endif
*/
__filebuf_type _M_filebuf;
public:
// Constructors/destructor:
/**
* @brief Default constructor.
*
* Initializes @c sb using its default constructor, and passes
* @c &sb to the base class initializer. Does not open any files
* (you haven't given it a filename to open).
*/
basic_fstream()
: __iostream_type(), _M_filebuf()
{ this->init(&_M_filebuf); }
/**
* @brief Create an input/output file stream.
* @param s Null terminated string specifying the filename.
* @param mode Open file in specified mode (see std::ios_base).
*
* Tip: When using std::string to hold the filename, you must use
* .c_str() before passing it to this constructor.
*/
explicit
basic_fstream(const char* __s,
ios_base::openmode __mode = ios_base::in | ios_base::out)
: __iostream_type(NULL), _M_filebuf()
{
this->init(&_M_filebuf);
this->open(__s, __mode);
}
/**
* @brief The destructor does nothing.
*
* The file is closed by the filebuf object, not the formatting
* stream.
*/
~basic_fstream()
{ }
// Members:
/**
* @brief Accessing the underlying buffer.
* @return The current basic_filebuf buffer.
*
* This hides both signatures of std::basic_ios::rdbuf().
*/
__filebuf_type*
rdbuf() const
{ return const_cast<__filebuf_type*>(&_M_filebuf); }
/**
* @brief Wrapper to test for an open file.
* @return @c rdbuf()->is_open()
*/
bool
is_open() { return _M_filebuf.is_open(); }
/**
* @brief Opens an external file.
* @param s The name of the file.
* @param mode The open mode flags.
*
* Calls @c std::basic_filebuf::open(s,mode). If that
* function fails, @c failbit is set in the stream's error state.
*
* Tip: When using std::string to hold the filename, you must use
* .c_str() before passing it to this constructor.
*/
void
open(const char* __s,
ios_base::openmode __mode = ios_base::in | ios_base::out)
{
if (!_M_filebuf.open(__s, __mode))
this->setstate(ios_base::failbit);
}
/**
* @brief Close the file.
*
* Calls @c std::basic_filebuf::close(). If that function
* fails, @c failbit is set in the stream's error state.
*/
void
close()
{
if (!_M_filebuf.close())
this->setstate(ios_base::failbit);
}
};
} // namespace std
#ifndef _GLIBCXX_EXPORT_TEMPLATE
# include <bits/fstream.tcc>
#endif
#endif /* _GLIBCXX_FSTREAM */
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