📄 basic_ios.h
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* f.setstate (std::ios_base::badbit);
*
* std::cerr << "Setting exception mask\n";
* f.exceptions (std::ios_base::badbit);
* }
* @endcode
*/
void
exceptions(iostate __except)
{
_M_exception = __except;
this->clear(_M_streambuf_state);
}
// Constructor/destructor:
/**
* @brief Constructor performs initialization.
*
* The parameter is passed by derived streams.
*/
explicit
basic_ios(basic_streambuf<_CharT, _Traits>* __sb)
: ios_base(), _M_tie(0), _M_fill(), _M_fill_init(false), _M_streambuf(0),
_M_ctype(0), _M_num_put(0), _M_num_get(0)
{ this->init(__sb); }
/**
* @brief Empty.
*
* The destructor does nothing. More specifically, it does not
* destroy the streambuf held by rdbuf().
*/
virtual
~basic_ios() { }
// Members:
/**
* @brief Fetches the current @e tied stream.
* @return A pointer to the tied stream, or NULL if the stream is
* not tied.
*
* A stream may be @e tied (or synchronized) to a second output
* stream. When this stream performs any I/O, the tied stream is
* first flushed. For example, @c std::cin is tied to @c std::cout.
*/
basic_ostream<_CharT, _Traits>*
tie() const
{ return _M_tie; }
/**
* @brief Ties this stream to an output stream.
* @param tiestr The output stream.
* @return The previously tied output stream, or NULL if the stream
* was not tied.
*
* This sets up a new tie; see tie() for more.
*/
basic_ostream<_CharT, _Traits>*
tie(basic_ostream<_CharT, _Traits>* __tiestr)
{
basic_ostream<_CharT, _Traits>* __old = _M_tie;
_M_tie = __tiestr;
return __old;
}
/**
* @brief Accessing the underlying buffer.
* @return The current stream buffer.
*
* This does not change the state of the stream.
*/
basic_streambuf<_CharT, _Traits>*
rdbuf() const
{ return _M_streambuf; }
/**
* @brief Changing the underlying buffer.
* @param sb The new stream buffer.
* @return The previous stream buffer.
*
* Associates a new buffer with the current stream, and clears the
* error state.
*
* Due to historical accidents which the LWG refuses to correct, the
* I/O library suffers from a design error: this function is hidden
* in derived classes by overrides of the zero-argument @c rdbuf(),
* which is non-virtual for hysterical raisins. As a result, you
* must use explicit qualifications to access this function via any
* derived class. For example:
*
* @code
* std::fstream foo; // or some other derived type
* std::streambuf* p = .....;
*
* foo.ios::rdbuf(p); // ios == basic_ios<char>
* @endcode
*/
basic_streambuf<_CharT, _Traits>*
rdbuf(basic_streambuf<_CharT, _Traits>* __sb);
/**
* @brief Copies fields of __rhs into this.
* @param __rhs The source values for the copies.
* @return Reference to this object.
*
* All fields of __rhs are copied into this object except that rdbuf()
* and rdstate() remain unchanged. All values in the pword and iword
* arrays are copied. Before copying, each callback is invoked with
* erase_event. After copying, each (new) callback is invoked with
* copyfmt_event. The final step is to copy exceptions().
*/
basic_ios&
copyfmt(const basic_ios& __rhs);
/**
* @brief Retreives the "empty" character.
* @return The current fill character.
*
* It defaults to a space (' ') in the current locale.
*/
char_type
fill() const
{
if (!_M_fill_init)
{
_M_fill = this->widen(' ');
_M_fill_init = true;
}
return _M_fill;
}
/**
* @brief Sets a new "empty" character.
* @param ch The new character.
* @return The previous fill character.
*
* The fill character is used to fill out space when P+ characters
* have been requested (e.g., via setw), Q characters are actually
* used, and Q<P. It defaults to a space (' ') in the current locale.
*/
char_type
fill(char_type __ch)
{
char_type __old = this->fill();
_M_fill = __ch;
return __old;
}
// Locales:
/**
* @brief Moves to a new locale.
* @param loc The new locale.
* @return The previous locale.
*
* Calls @c ios_base::imbue(loc), and if a stream buffer is associated
* with this stream, calls that buffer's @c pubimbue(loc).
*
* Additional l10n notes are at
* http://gcc.gnu.org/onlinedocs/libstdc++/22_locale/howto.html
*/
locale
imbue(const locale& __loc);
/**
* @brief Squeezes characters.
* @param c The character to narrow.
* @param dfault The character to narrow.
* @return The narrowed character.
*
* Maps a character of @c char_type to a character of @c char,
* if possible.
*
* Returns the result of
* @code
* std::use_facet<ctype<char_type> >(getloc()).narrow(c,dfault)
* @endcode
*
* Additional l10n notes are at
* http://gcc.gnu.org/onlinedocs/libstdc++/22_locale/howto.html
*/
char
narrow(char_type __c, char __dfault) const;
/**
* @brief Widens characters.
* @param c The character to widen.
* @return The widened character.
*
* Maps a character of @c char to a character of @c char_type.
*
* Returns the result of
* @code
* std::use_facet<ctype<char_type> >(getloc()).widen(c)
* @endcode
*
* Additional l10n notes are at
* http://gcc.gnu.org/onlinedocs/libstdc++/22_locale/howto.html
*/
char_type
widen(char __c) const;
protected:
// 27.4.5.1 basic_ios constructors
/**
* @brief Empty.
*
* The default constructor does nothing and is not normally
* accessible to users.
*/
basic_ios()
: ios_base(), _M_tie(0), _M_fill(char_type()), _M_fill_init(false),
_M_streambuf(0), _M_ctype(0), _M_num_put(0), _M_num_get(0)
{ }
/**
* @brief All setup is performed here.
*
* This is called from the public constructor. It is not virtual and
* cannot be redefined.
*/
void
init(basic_streambuf<_CharT, _Traits>* __sb);
void
_M_cache_locale(const locale& __loc);
};
} // namespace std
#ifndef _GLIBCXX_EXPORT_TEMPLATE
#include <bits/basic_ios.tcc>
#endif
#endif /* _BASIC_IOS_H */
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