📄 ios_base.h
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// Guaranteed storage.
// The first 5 iword and pword slots are reserved for internal use.
static const int _S_local_word_size = 8;
_Words _M_local_word[_S_local_word_size];
// Allocated storage.
int _M_word_size;
_Words* _M_word;
_Words&
_M_grow_words(int __index, bool __iword);
// Members for locale and locale caching.
locale _M_ios_locale;
void
_M_init();
public:
// 27.4.2.1.6 Class ios_base::Init
// Used to initialize standard streams. In theory, g++ could use
// -finit-priority to order this stuff correctly without going
// through these machinations.
class Init
{
friend class ios_base;
public:
Init();
~Init();
private:
static _Atomic_word _S_refcount;
static bool _S_synced_with_stdio;
};
// [27.4.2.2] fmtflags state functions
/**
* @brief Access to format flags.
* @return The format control flags for both input and output.
*/
inline fmtflags
flags() const { return _M_flags; }
/**
* @brief Setting new format flags all at once.
* @param fmtfl The new flags to set.
* @return The previous format control flags.
*
* This function overwrites all the format flags with @a fmtfl.
*/
inline fmtflags
flags(fmtflags __fmtfl)
{
fmtflags __old = _M_flags;
_M_flags = __fmtfl;
return __old;
}
/**
* @brief Setting new format flags.
* @param fmtfl Additional flags to set.
* @return The previous format control flags.
*
* This function sets additional flags in format control. Flags that
* were previously set remain set.
*/
inline fmtflags
setf(fmtflags __fmtfl)
{
fmtflags __old = _M_flags;
_M_flags |= __fmtfl;
return __old;
}
/**
* @brief Setting new format flags.
* @param fmtfl Additional flags to set.
* @param mask The flags mask for @a fmtfl.
* @return The previous format control flags.
*
* This function clears @a mask in the format flags, then sets
* @a fmtfl @c & @a mask. An example mask is @c ios_base::adjustfield.
*/
inline fmtflags
setf(fmtflags __fmtfl, fmtflags __mask)
{
fmtflags __old = _M_flags;
_M_flags &= ~__mask;
_M_flags |= (__fmtfl & __mask);
return __old;
}
/**
* @brief Clearing format flags.
* @param mask The flags to unset.
*
* This function clears @a mask in the format flags.
*/
inline void
unsetf(fmtflags __mask) { _M_flags &= ~__mask; }
/**
* @brief Flags access.
* @return The precision to generate on certain output operations.
*
* @if maint
* Be careful if you try to give a definition of "precision" here; see
* DR 189.
* @endif
*/
inline streamsize
precision() const { return _M_precision; }
/**
* @brief Changing flags.
* @param prec The new precision value.
* @return The previous value of precision().
*/
inline streamsize
precision(streamsize __prec)
{
streamsize __old = _M_precision;
_M_precision = __prec;
return __old;
}
/**
* @brief Flags access.
* @return The minimum field width to generate on output operations.
*
* "Minimum field width" refers to the number of characters.
*/
inline streamsize
width() const { return _M_width; }
/**
* @brief Changing flags.
* @param wide The new width value.
* @return The previous value of width().
*/
inline streamsize
width(streamsize __wide)
{
streamsize __old = _M_width;
_M_width = __wide;
return __old;
}
// [27.4.2.4] ios_base static members
/**
* @brief Interaction with the standard C I/O objects.
* @param sync Whether to synchronize or not.
* @return True if the standard streams were previously synchronized.
*
* The synchronization referred to is @e only that between the standard
* C facilities (e.g., stdout) and the standard C++ objects (e.g.,
* cout). User-declared streams are unaffected. See
* http://gcc.gnu.org/onlinedocs/libstdc++/27_io/howto.html#8 for more.
*/
static bool
sync_with_stdio(bool __sync = true);
// [27.4.2.3] ios_base locale functions
/**
* @brief Setting a new locale.
* @param loc The new locale.
* @return The previous locale.
*
* Sets the new locale for this stream, and then invokes each callback
* with imbue_event.
*/
locale
imbue(const locale& __loc);
/**
* @brief Locale access
* @return A copy of the current locale.
*
* If @c imbue(loc) has previously been called, then this function
* returns @c loc. Otherwise, it returns a copy of @c std::locale(),
* the global C++ locale.
*/
inline locale
getloc() const { return _M_ios_locale; }
/**
* @brief Locale access
* @return A reference to the current locale.
*
* Like getloc above, but returns a reference instead of
* generating a copy.
*/
inline const locale&
_M_getloc() const { return _M_ios_locale; }
// [27.4.2.5] ios_base storage functions
/**
* @brief Access to unique indices.
* @return An integer different from all previous calls.
*
* This function returns a unique integer every time it is called. It
* can be used for any purpose, but is primarily intended to be a unique
* index for the iword and pword functions. The expectation is that an
* application calls xalloc in order to obtain an index in the iword and
* pword arrays that can be used without fear of conflict.
*
* The implementation maintains a static variable that is incremented and
* returned on each invocation. xalloc is guaranteed to return an index
* that is safe to use in the iword and pword arrays.
*/
static int
xalloc() throw();
/**
* @brief Access to integer array.
* @param __ix Index into the array.
* @return A reference to an integer associated with the index.
*
* The iword function provides access to an array of integers that can be
* used for any purpose. The array grows as required to hold the
* supplied index. All integers in the array are initialized to 0.
*
* The implementation reserves several indices. You should use xalloc to
* obtain an index that is safe to use. Also note that since the array
* can grow dynamically, it is not safe to hold onto the reference.
*/
inline long&
iword(int __ix)
{
_Words& __word = (__ix < _M_word_size)
? _M_word[__ix] : _M_grow_words(__ix, true);
return __word._M_iword;
}
/**
* @brief Access to void pointer array.
* @param __ix Index into the array.
* @return A reference to a void* associated with the index.
*
* The pword function provides access to an array of pointers that can be
* used for any purpose. The array grows as required to hold the
* supplied index. All pointers in the array are initialized to 0.
*
* The implementation reserves several indices. You should use xalloc to
* obtain an index that is safe to use. Also note that since the array
* can grow dynamically, it is not safe to hold onto the reference.
*/
inline void*&
pword(int __ix)
{
_Words& __word = (__ix < _M_word_size)
? _M_word[__ix] : _M_grow_words(__ix, false);
return __word._M_pword;
}
// Destructor
/**
* Invokes each callback with erase_event. Destroys local storage.
*
* Note that the ios_base object for the standard streams never gets
* destroyed. As a result, any callbacks registered with the standard
* streams will not get invoked with erase_event (unless copyfmt is
* used).
*/
virtual ~ios_base();
protected:
ios_base();
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 50. Copy constructor and assignment operator of ios_base
private:
ios_base(const ios_base&);
ios_base&
operator=(const ios_base&);
};
// [27.4.5.1] fmtflags manipulators
/// Calls base.setf(ios_base::boolalpha).
inline ios_base&
boolalpha(ios_base& __base)
{
__base.setf(ios_base::boolalpha);
return __base;
}
/// Calls base.unsetf(ios_base::boolalpha).
inline ios_base&
noboolalpha(ios_base& __base)
{
__base.unsetf(ios_base::boolalpha);
return __base;
}
/// Calls base.setf(ios_base::showbase).
inline ios_base&
showbase(ios_base& __base)
{
__base.setf(ios_base::showbase);
return __base;
}
/// Calls base.unsetf(ios_base::showbase).
inline ios_base&
noshowbase(ios_base& __base)
{
__base.unsetf(ios_base::showbase);
return __base;
}
/// Calls base.setf(ios_base::showpoint).
inline ios_base&
showpoint(ios_base& __base)
{
__base.setf(ios_base::showpoint);
return __base;
}
/// Calls base.unsetf(ios_base::showpoint).
inline ios_base&
noshowpoint(ios_base& __base)
{
__base.unsetf(ios_base::showpoint);
return __base;
}
/// Calls base.setf(ios_base::showpos).
inline ios_base&
showpos(ios_base& __base)
{
__base.setf(ios_base::showpos);
return __base;
}
/// Calls base.unsetf(ios_base::showpos).
inline ios_base&
noshowpos(ios_base& __base)
{
__base.unsetf(ios_base::showpos);
return __base;
}
/// Calls base.setf(ios_base::skipws).
inline ios_base&
skipws(ios_base& __base)
{
__base.setf(ios_base::skipws);
return __base;
}
/// Calls base.unsetf(ios_base::skipws).
inline ios_base&
noskipws(ios_base& __base)
{
__base.unsetf(ios_base::skipws);
return __base;
}
/// Calls base.setf(ios_base::uppercase).
inline ios_base&
uppercase(ios_base& __base)
{
__base.setf(ios_base::uppercase);
return __base;
}
/// Calls base.unsetf(ios_base::uppercase).
inline ios_base&
nouppercase(ios_base& __base)
{
__base.unsetf(ios_base::uppercase);
return __base;
}
/// Calls base.setf(ios_base::unitbuf).
inline ios_base&
unitbuf(ios_base& __base)
{
__base.setf(ios_base::unitbuf);
return __base;
}
/// Calls base.unsetf(ios_base::unitbuf).
inline ios_base&
nounitbuf(ios_base& __base)
{
__base.unsetf(ios_base::unitbuf);
return __base;
}
// [27.4.5.2] adjustfield anipulators
/// Calls base.setf(ios_base::internal, ios_base::adjustfield).
inline ios_base&
internal(ios_base& __base)
{
__base.setf(ios_base::internal, ios_base::adjustfield);
return __base;
}
/// Calls base.setf(ios_base::left, ios_base::adjustfield).
inline ios_base&
left(ios_base& __base)
{
__base.setf(ios_base::left, ios_base::adjustfield);
return __base;
}
/// Calls base.setf(ios_base::right, ios_base::adjustfield).
inline ios_base&
right(ios_base& __base)
{
__base.setf(ios_base::right, ios_base::adjustfield);
return __base;
}
// [27.4.5.3] basefield anipulators
/// Calls base.setf(ios_base::dec, ios_base::basefield).
inline ios_base&
dec(ios_base& __base)
{
__base.setf(ios_base::dec, ios_base::basefield);
return __base;
}
/// Calls base.setf(ios_base::hex, ios_base::basefield).
inline ios_base&
hex(ios_base& __base)
{
__base.setf(ios_base::hex, ios_base::basefield);
return __base;
}
/// Calls base.setf(ios_base::oct, ios_base::basefield).
inline ios_base&
oct(ios_base& __base)
{
__base.setf(ios_base::oct, ios_base::basefield);
return __base;
}
// [27.4.5.4] floatfield anipulators
/// Calls base.setf(ios_base::fixed, ios_base::floatfield).
inline ios_base&
fixed(ios_base& __base)
{
__base.setf(ios_base::fixed, ios_base::floatfield);
return __base;
}
/// Calls base.setf(ios_base::scientific, ios_base::floatfield).
inline ios_base&
scientific(ios_base& __base)
{
__base.setf(ios_base::scientific, ios_base::floatfield);
return __base;
}
} // namespace std
#endif /* _IOS_BASE_H */
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