ios_base.h

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00001 // Iostreams base classes -*- C++ -*-
00002 
00003 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
00004 // 2006, 2007, 2008
00005 // Free Software Foundation, Inc.
00006 //
00007 // This file is part of the GNU ISO C++ Library.  This library is free
00008 // software; you can redistribute it and/or modify it under the
00009 // terms of the GNU General Public License as published by the
00010 // Free Software Foundation; either version 2, or (at your option)
00011 // any later version.
00012 
00013 // This library is distributed in the hope that it will be useful,
00014 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00015 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00016 // GNU General Public License for more details.
00017 
00018 // You should have received a copy of the GNU General Public License along
00019 // with this library; see the file COPYING.  If not, write to the Free
00020 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
00021 // USA.
00022 
00023 // As a special exception, you may use this file as part of a free software
00024 // library without restriction.  Specifically, if other files instantiate
00025 // templates or use macros or inline functions from this file, or you compile
00026 // this file and link it with other files to produce an executable, this
00027 // file does not by itself cause the resulting executable to be covered by
00028 // the GNU General Public License.  This exception does not however
00029 // invalidate any other reasons why the executable file might be covered by
00030 // the GNU General Public License.
00031 
00032 /** @file ios_base.h
00033  *  This is an internal header file, included by other library headers.
00034  *  You should not attempt to use it directly.
00035  */
00036 
00037 //
00038 // ISO C++ 14882: 27.4  Iostreams base classes
00039 //
00040 
00041 #ifndef _IOS_BASE_H
00042 #define _IOS_BASE_H 1
00043 
00044 #pragma GCC system_header
00045 
00046 #include <ext/atomicity.h>
00047 #include <bits/localefwd.h>
00048 #include <bits/locale_classes.h>
00049 #include <cstdio>  // For SEEK_CUR, SEEK_END
00050 
00051 _GLIBCXX_BEGIN_NAMESPACE(std)
00052 
00053   // The following definitions of bitmask types are enums, not ints,
00054   // as permitted (but not required) in the standard, in order to provide
00055   // better type safety in iostream calls.  A side effect is that
00056   // expressions involving them are no longer compile-time constants.
00057   enum _Ios_Fmtflags 
00058     { 
00059       _S_boolalpha  = 1L << 0,
00060       _S_dec        = 1L << 1,
00061       _S_fixed      = 1L << 2,
00062       _S_hex        = 1L << 3,
00063       _S_internal   = 1L << 4,
00064       _S_left       = 1L << 5,
00065       _S_oct        = 1L << 6,
00066       _S_right      = 1L << 7,
00067       _S_scientific     = 1L << 8,
00068       _S_showbase   = 1L << 9,
00069       _S_showpoint  = 1L << 10,
00070       _S_showpos    = 1L << 11,
00071       _S_skipws     = 1L << 12,
00072       _S_unitbuf    = 1L << 13,
00073       _S_uppercase  = 1L << 14,
00074       _S_adjustfield    = _S_left | _S_right | _S_internal,
00075       _S_basefield  = _S_dec | _S_oct | _S_hex,
00076       _S_floatfield     = _S_scientific | _S_fixed,
00077       _S_ios_fmtflags_end = 1L << 16 
00078     };
00079 
00080   inline _Ios_Fmtflags
00081   operator&(_Ios_Fmtflags __a, _Ios_Fmtflags __b)
00082   { return _Ios_Fmtflags(static_cast<int>(__a) & static_cast<int>(__b)); }
00083 
00084   inline _Ios_Fmtflags
00085   operator|(_Ios_Fmtflags __a, _Ios_Fmtflags __b)
00086   { return _Ios_Fmtflags(static_cast<int>(__a) | static_cast<int>(__b)); }
00087 
00088   inline _Ios_Fmtflags
00089   operator^(_Ios_Fmtflags __a, _Ios_Fmtflags __b)
00090   { return _Ios_Fmtflags(static_cast<int>(__a) ^ static_cast<int>(__b)); }
00091 
00092   inline _Ios_Fmtflags&
00093   operator|=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b)
00094   { return __a = __a | __b; }
00095 
00096   inline _Ios_Fmtflags&
00097   operator&=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b)
00098   { return __a = __a & __b; }
00099 
00100   inline _Ios_Fmtflags&
00101   operator^=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b)
00102   { return __a = __a ^ __b; }
00103 
00104   inline _Ios_Fmtflags
00105   operator~(_Ios_Fmtflags __a)
00106   { return _Ios_Fmtflags(~static_cast<int>(__a)); }
00107 
00108 
00109   enum _Ios_Openmode 
00110     { 
00111       _S_app        = 1L << 0,
00112       _S_ate        = 1L << 1,
00113       _S_bin        = 1L << 2,
00114       _S_in         = 1L << 3,
00115       _S_out        = 1L << 4,
00116       _S_trunc      = 1L << 5,
00117       _S_ios_openmode_end = 1L << 16 
00118     };
00119 
00120   inline _Ios_Openmode
00121   operator&(_Ios_Openmode __a, _Ios_Openmode __b)
00122   { return _Ios_Openmode(static_cast<int>(__a) & static_cast<int>(__b)); }
00123 
00124   inline _Ios_Openmode
00125   operator|(_Ios_Openmode __a, _Ios_Openmode __b)
00126   { return _Ios_Openmode(static_cast<int>(__a) | static_cast<int>(__b)); }
00127 
00128   inline _Ios_Openmode
00129   operator^(_Ios_Openmode __a, _Ios_Openmode __b)
00130   { return _Ios_Openmode(static_cast<int>(__a) ^ static_cast<int>(__b)); }
00131 
00132   inline _Ios_Openmode&
00133   operator|=(_Ios_Openmode& __a, _Ios_Openmode __b)
00134   { return __a = __a | __b; }
00135 
00136   inline _Ios_Openmode&
00137   operator&=(_Ios_Openmode& __a, _Ios_Openmode __b)
00138   { return __a = __a & __b; }
00139 
00140   inline _Ios_Openmode&
00141   operator^=(_Ios_Openmode& __a, _Ios_Openmode __b)
00142   { return __a = __a ^ __b; }
00143 
00144   inline _Ios_Openmode
00145   operator~(_Ios_Openmode __a)
00146   { return _Ios_Openmode(~static_cast<int>(__a)); }
00147 
00148 
00149   enum _Ios_Iostate
00150     { 
00151       _S_goodbit        = 0,
00152       _S_badbit         = 1L << 0,
00153       _S_eofbit         = 1L << 1,
00154       _S_failbit        = 1L << 2,
00155       _S_ios_iostate_end = 1L << 16 
00156     };
00157 
00158   inline _Ios_Iostate
00159   operator&(_Ios_Iostate __a, _Ios_Iostate __b)
00160   { return _Ios_Iostate(static_cast<int>(__a) & static_cast<int>(__b)); }
00161 
00162   inline _Ios_Iostate
00163   operator|(_Ios_Iostate __a, _Ios_Iostate __b)
00164   { return _Ios_Iostate(static_cast<int>(__a) | static_cast<int>(__b)); }
00165 
00166   inline _Ios_Iostate
00167   operator^(_Ios_Iostate __a, _Ios_Iostate __b)
00168   { return _Ios_Iostate(static_cast<int>(__a) ^ static_cast<int>(__b)); }
00169 
00170   inline _Ios_Iostate&
00171   operator|=(_Ios_Iostate& __a, _Ios_Iostate __b)
00172   { return __a = __a | __b; }
00173 
00174   inline _Ios_Iostate&
00175   operator&=(_Ios_Iostate& __a, _Ios_Iostate __b)
00176   { return __a = __a & __b; }
00177 
00178   inline _Ios_Iostate&
00179   operator^=(_Ios_Iostate& __a, _Ios_Iostate __b)
00180   { return __a = __a ^ __b; }
00181 
00182   inline _Ios_Iostate
00183   operator~(_Ios_Iostate __a)
00184   { return _Ios_Iostate(~static_cast<int>(__a)); }
00185 
00186   enum _Ios_Seekdir 
00187     { 
00188       _S_beg = 0,
00189       _S_cur = SEEK_CUR,
00190       _S_end = SEEK_END,
00191       _S_ios_seekdir_end = 1L << 16 
00192     };
00193 
00194   // 27.4.2  Class ios_base
00195   /**
00196    *  @brief  The base of the I/O class hierarchy.
00197    *
00198    *  This class defines everything that can be defined about I/O that does
00199    *  not depend on the type of characters being input or output.  Most
00200    *  people will only see @c ios_base when they need to specify the full
00201    *  name of the various I/O flags (e.g., the openmodes).
00202   */
00203   class ios_base
00204   {
00205   public:
00206 
00207     // 27.4.2.1.1  Class ios_base::failure
00208     /// These are thrown to indicate problems.  Doc me.
00209     class failure : public exception
00210     {
00211     public:
00212       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00213       // 48.  Use of non-existent exception constructor
00214       explicit
00215       failure(const string& __str) throw();
00216 
00217       // This declaration is not useless:
00218       // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118
00219       virtual
00220       ~failure() throw();
00221 
00222       virtual const char*
00223       what() const throw();
00224 
00225     private:
00226       string _M_msg;
00227     };
00228 
00229     // 27.4.2.1.2  Type ios_base::fmtflags
00230     /**
00231      *  @brief This is a bitmask type.
00232      *
00233      *  @c "_Ios_Fmtflags" is implementation-defined, but it is valid to
00234      *  perform bitwise operations on these values and expect the Right
00235      *  Thing to happen.  Defined objects of type fmtflags are:
00236      *  - boolalpha
00237      *  - dec
00238      *  - fixed
00239      *  - hex
00240      *  - internal
00241      *  - left
00242      *  - oct
00243      *  - right
00244      *  - scientific
00245      *  - showbase
00246      *  - showpoint
00247      *  - showpos
00248      *  - skipws
00249      *  - unitbuf
00250      *  - uppercase
00251      *  - adjustfield
00252      *  - basefield
00253      *  - floatfield
00254     */
00255     typedef _Ios_Fmtflags fmtflags;
00256 
00257     /// Insert/extract @c bool in alphabetic rather than numeric format.
00258     static const fmtflags boolalpha =   _S_boolalpha;
00259 
00260     /// Converts integer input or generates integer output in decimal base.
00261     static const fmtflags dec =         _S_dec;
00262 
00263     /// Generate floating-point output in fixed-point notation.
00264     static const fmtflags fixed =       _S_fixed;
00265 
00266     /// Converts integer input or generates integer output in hexadecimal base.
00267     static const fmtflags hex =         _S_hex;
00268 
00269     /// Adds fill characters at a designated internal point in certain
00270     /// generated output, or identical to @c right if no such point is
00271     /// designated.
00272     static const fmtflags internal =    _S_internal;
00273 
00274     /// Adds fill characters on the right (final positions) of certain
00275     /// generated output.  (I.e., the thing you print is flush left.)
00276     static const fmtflags left =        _S_left;
00277 
00278     /// Converts integer input or generates integer output in octal base.
00279     static const fmtflags oct =         _S_oct;
00280 
00281     /// Adds fill characters on the left (initial positions) of certain
00282     /// generated output.  (I.e., the thing you print is flush right.)
00283     static const fmtflags right =       _S_right;
00284 
00285     /// Generates floating-point output in scientific notation.
00286     static const fmtflags scientific =  _S_scientific;
00287 
00288     /// Generates a prefix indicating the numeric base of generated integer
00289     /// output.
00290     static const fmtflags showbase =    _S_showbase;
00291 
00292     /// Generates a decimal-point character unconditionally in generated
00293     /// floating-point output.
00294     static const fmtflags showpoint =   _S_showpoint;
00295 
00296     /// Generates a + sign in non-negative generated numeric output.
00297     static const fmtflags showpos =     _S_showpos;
00298 
00299     /// Skips leading white space before certain input operations.
00300     static const fmtflags skipws =      _S_skipws;
00301 
00302     /// Flushes output after each output operation.
00303     static const fmtflags unitbuf =     _S_unitbuf;
00304 
00305     /// Replaces certain lowercase letters with their uppercase equivalents
00306     /// in generated output.
00307     static const fmtflags uppercase =   _S_uppercase;
00308 
00309     /// A mask of left|right|internal.  Useful for the 2-arg form of @c setf.
00310     static const fmtflags adjustfield = _S_adjustfield;
00311 
00312     /// A mask of dec|oct|hex.  Useful for the 2-arg form of @c setf.
00313     static const fmtflags basefield =   _S_basefield;
00314 
00315     /// A mask of scientific|fixed.  Useful for the 2-arg form of @c setf.
00316     static const fmtflags floatfield =  _S_floatfield;
00317 
00318     // 27.4.2.1.3  Type ios_base::iostate
00319     /**
00320      *  @brief This is a bitmask type.
00321      *
00322      *  @c "_Ios_Iostate" is implementation-defined, but it is valid to
00323      *  perform bitwise operations on these values and expect the Right
00324      *  Thing to happen.  Defined objects of type iostate are:
00325      *  - badbit
00326      *  - eofbit
00327      *  - failbit
00328      *  - goodbit
00329     */
00330     typedef _Ios_Iostate iostate;
00331 
00332     /// Indicates a loss of integrity in an input or output sequence (such
00333     /// as an irrecoverable read error from a file).
00334     static const iostate badbit =   _S_badbit;
00335 
00336     /// Indicates that an input operation reached the end of an input sequence.
00337     static const iostate eofbit =   _S_eofbit;
00338 
00339     /// Indicates that an input operation failed to read the expected
00340     /// characters, or that an output operation failed to generate the
00341     /// desired characters.
00342     static const iostate failbit =  _S_failbit;
00343 
00344     /// Indicates all is well.
00345     static const iostate goodbit =  _S_goodbit;
00346 
00347     // 27.4.2.1.4  Type ios_base::openmode
00348     /**
00349      *  @brief This is a bitmask type.
00350      *
00351      *  @c "_Ios_Openmode" is implementation-defined, but it is valid to
00352      *  perform bitwise operations on these values and expect the Right
00353      *  Thing to happen.  Defined objects of type openmode are:
00354      *  - app
00355      *  - ate
00356      *  - binary
00357      *  - in
00358      *  - out
00359      *  - trunc
00360     */
00361     typedef _Ios_Openmode openmode;
00362 
00363     /// Seek to end before each write.
00364     static const openmode app =     _S_app;
00365 
00366     /// Open and seek to end immediately after opening.
00367     static const openmode ate =     _S_ate;
00368 
00369     /// Perform input and output in binary mode (as opposed to text mode).
00370     /// This is probably not what you think it is; see
00371     /// http://gcc.gnu.org/onlinedocs/libstdc++/27_io/howto.html#3 and
00372     /// http://gcc.gnu.org/onlinedocs/libstdc++/27_io/howto.html#7 for more.
00373     static const openmode binary =  _S_bin;
00374 
00375     /// Open for input.  Default for @c ifstream and fstream.
00376     static const openmode in =      _S_in;
00377 
00378     /// Open for output.  Default for @c ofstream and fstream.
00379     static const openmode out =     _S_out;
00380 
00381     /// Open for input.  Default for @c ofstream.
00382     static const openmode trunc =   _S_trunc;
00383 
00384     // 27.4.2.1.5  Type ios_base::seekdir
00385     /**
00386      *  @brief This is an enumerated type.
00387      *
00388      *  @c "_Ios_Seekdir" is implementation-defined.  Defined values
00389      *  of type seekdir are:
00390      *  - beg
00391      *  - cur, equivalent to @c SEEK_CUR in the C standard library.
00392      *  - end, equivalent to @c SEEK_END in the C standard library.
00393     */
00394     typedef _Ios_Seekdir seekdir;
00395 
00396     /// Request a seek relative to the beginning of the stream.
00397     static const seekdir beg =      _S_beg;
00398 
00399     /// Request a seek relative to the current position within the sequence.
00400     static const seekdir cur =      _S_cur;
00401 
00402     /// Request a seek relative to the current end of the sequence.
00403     static const seekdir end =      _S_end;
00404 
00405     // Annex D.6
00406     typedef int io_state;
00407     typedef int open_mode;
00408     typedef int seek_dir;
00409 
00410     typedef std::streampos streampos;
00411     typedef std::streamoff streamoff;
00412 
00413     // Callbacks;
00414     /**
00415      *  @brief  The set of events that may be passed to an event callback.
00416      *
00417      *  erase_event is used during ~ios() and copyfmt().  imbue_event is used
00418      *  during imbue().  copyfmt_event is used during copyfmt().
00419     */
00420     enum event
00421     {
00422       erase_event,
00423       imbue_event,
00424       copyfmt_event
00425     };
00426 
00427     /**
00428      *  @brief  The type of an event callback function.
00429      *  @param  event  One of the members of the event enum.
00430      *  @param  ios_base  Reference to the ios_base object.
00431      *  @param  int  The integer provided when the callback was registered.
00432      *
00433      *  Event callbacks are user defined functions that get called during
00434      *  several ios_base and basic_ios functions, specifically imbue(),
00435      *  copyfmt(), and ~ios().
00436     */
00437     typedef void (*event_callback) (event, ios_base&, int);
00438 
00439     /**
00440      *  @brief  Add the callback __fn with parameter __index.
00441      *  @param  __fn  The function to add.
00442      *  @param  __index  The integer to pass to the function when invoked.
00443      *
00444      *  Registers a function as an event callback with an integer parameter to
00445      *  be passed to the function when invoked.  Multiple copies of the
00446      *  function are allowed.  If there are multiple callbacks, they are
00447      *  invoked in the order they were registered.
00448     */
00449     void
00450     register_callback(event_callback __fn, int __index);
00451 
00452   protected:
00453     //@{
00454     /**
00455      *  ios_base data members (doc me)
00456     */
00457     streamsize      _M_precision;
00458     streamsize      _M_width;
00459     fmtflags        _M_flags;
00460     iostate     _M_exception;
00461     iostate     _M_streambuf_state;
00462     //@}
00463 
00464     // 27.4.2.6  Members for callbacks
00465     // 27.4.2.6  ios_base callbacks
00466     struct _Callback_list
00467     {
00468       // Data Members
00469       _Callback_list*       _M_next;
00470       ios_base::event_callback  _M_fn;
00471       int           _M_index;
00472       _Atomic_word      _M_refcount;  // 0 means one reference.
00473 
00474       _Callback_list(ios_base::event_callback __fn, int __index,
00475              _Callback_list* __cb)
00476       : _M_next(__cb), _M_fn(__fn), _M_index(__index), _M_refcount(0) { }
00477 
00478       void
00479       _M_add_reference() { __gnu_cxx::__atomic_add_dispatch(&_M_refcount, 1); }
00480 
00481       // 0 => OK to delete.
00482       int
00483       _M_remove_reference() 
00484       { return __gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1); }
00485     };
00486 
00487      _Callback_list*    _M_callbacks;
00488 
00489     void
00490     _M_call_callbacks(event __ev) throw();
00491 
00492     void
00493     _M_dispose_callbacks(void);
00494 
00495     // 27.4.2.5  Members for iword/pword storage
00496     struct _Words
00497     {
00498       void* _M_pword;
00499       long  _M_iword;
00500       _Words() : _M_pword(0), _M_iword(0) { }
00501     };
00502 
00503     // Only for failed iword/pword calls.
00504     _Words      _M_word_zero;
00505 
00506     // Guaranteed storage.
00507     // The first 5 iword and pword slots are reserved for internal use.
00508     enum { _S_local_word_size = 8 };
00509     _Words      _M_local_word[_S_local_word_size];
00510 
00511     // Allocated storage.
00512     int         _M_word_size;
00513     _Words*     _M_word;
00514 
00515     _Words&
00516     _M_grow_words(int __index, bool __iword);
00517 
00518     // Members for locale and locale caching.
00519     locale      _M_ios_locale;
00520 
00521     void
00522     _M_init();
00523 
00524   public:
00525 
00526     // 27.4.2.1.6  Class ios_base::Init
00527     // Used to initialize standard streams. In theory, g++ could use
00528     // -finit-priority to order this stuff correctly without going
00529     // through these machinations.
00530     class Init
00531     {
00532       friend class ios_base;
00533     public:
00534       Init();
00535       ~Init();
00536 
00537     private:
00538       static _Atomic_word   _S_refcount;
00539       static bool       _S_synced_with_stdio;
00540     };
00541 
00542     // [27.4.2.2] fmtflags state functions
00543     /**
00544      *  @brief  Access to format flags.
00545      *  @return  The format control flags for both input and output.
00546     */
00547     fmtflags
00548     flags() const
00549     { return _M_flags; }
00550 
00551     /**
00552      *  @brief  Setting new format flags all at once.
00553      *  @param  fmtfl  The new flags to set.
00554      *  @return  The previous format control flags.
00555      *
00556      *  This function overwrites all the format flags with @a fmtfl.
00557     */
00558     fmtflags
00559     flags(fmtflags __fmtfl)
00560     {
00561       fmtflags __old = _M_flags;
00562       _M_flags = __fmtfl;
00563       return __old;
00564     }
00565 
00566     /**
00567      *  @brief  Setting new format flags.
00568      *  @param  fmtfl  Additional flags to set.
00569      *  @return  The previous format control flags.
00570      *
00571      *  This function sets additional flags in format control.  Flags that
00572      *  were previously set remain set.
00573     */
00574     fmtflags
00575     setf(fmtflags __fmtfl)
00576     {
00577       fmtflags __old = _M_flags;
00578       _M_flags |= __fmtfl;
00579       return __old;
00580     }
00581 
00582     /**
00583      *  @brief  Setting new format flags.
00584      *  @param  fmtfl  Additional flags to set.
00585      *  @param  mask  The flags mask for @a fmtfl.
00586      *  @return  The previous format control flags.
00587      *
00588      *  This function clears @a mask in the format flags, then sets
00589      *  @a fmtfl @c & @a mask.  An example mask is @c ios_base::adjustfield.
00590     */
00591     fmtflags
00592     setf(fmtflags __fmtfl, fmtflags __mask)
00593     {
00594       fmtflags __old = _M_flags;
00595       _M_flags &= ~__mask;
00596       _M_flags |= (__fmtfl & __mask);
00597       return __old;
00598     }
00599 
00600     /**
00601      *  @brief  Clearing format flags.
00602      *  @param  mask  The flags to unset.
00603      *
00604      *  This function clears @a mask in the format flags.
00605     */
00606     void
00607     unsetf(fmtflags __mask)
00608     { _M_flags &= ~__mask; }
00609 
00610     /**
00611      *  @brief  Flags access.
00612      *  @return  The precision to generate on certain output operations.
00613      *
00614      *  Be careful if you try to give a definition of "precision" here; see
00615      *  DR 189.
00616     */
00617     streamsize
00618     precision() const
00619     { return _M_precision; }
00620 
00621     /**
00622      *  @brief  Changing flags.
00623      *  @param  prec  The new precision value.
00624      *  @return  The previous value of precision().
00625     */
00626     streamsize
00627     precision(streamsize __prec)
00628     {
00629       streamsize __old = _M_precision;
00630       _M_precision = __prec;
00631       return __old;
00632     }
00633 
00634     /**
00635      *  @brief  Flags access.
00636      *  @return  The minimum field width to generate on output operations.
00637      *
00638      *  "Minimum field width" refers to the number of characters.
00639     */
00640     streamsize
00641     width() const
00642     { return _M_width; }
00643 
00644     /**
00645      *  @brief  Changing flags.
00646      *  @param  wide  The new width value.
00647      *  @return  The previous value of width().
00648     */
00649     streamsize
00650     width(streamsize __wide)
00651     {
00652       streamsize __old = _M_width;
00653       _M_width = __wide;
00654       return __old;
00655     }
00656 
00657     // [27.4.2.4] ios_base static members
00658     /**
00659      *  @brief  Interaction with the standard C I/O objects.
00660      *  @param  sync  Whether to synchronize or not.
00661      *  @return  True if the standard streams were previously synchronized.
00662      *
00663      *  The synchronization referred to is @e only that between the standard
00664      *  C facilities (e.g., stdout) and the standard C++ objects (e.g.,
00665      *  cout).  User-declared streams are unaffected.  See
00666      *  http://gcc.gnu.org/onlinedocs/libstdc++/27_io/howto.html#8 for more.
00667     */
00668     static bool
00669     sync_with_stdio(bool __sync = true);
00670 
00671     // [27.4.2.3] ios_base locale functions
00672     /**
00673      *  @brief  Setting a new locale.
00674      *  @param  loc  The new locale.
00675      *  @return  The previous locale.
00676      *
00677      *  Sets the new locale for this stream, and then invokes each callback
00678      *  with imbue_event.
00679     */
00680     locale
00681     imbue(const locale& __loc);
00682 
00683     /**
00684      *  @brief  Locale access
00685      *  @return  A copy of the current locale.
00686      *
00687      *  If @c imbue(loc) has previously been called, then this function
00688      *  returns @c loc.  Otherwise, it returns a copy of @c std::locale(),
00689      *  the global C++ locale.
00690     */
00691     locale
00692     getloc() const
00693     { return _M_ios_locale; }
00694 
00695     /**
00696      *  @brief  Locale access
00697      *  @return  A reference to the current locale.
00698      *
00699      *  Like getloc above, but returns a reference instead of
00700      *  generating a copy.
00701     */
00702     const locale&
00703     _M_getloc() const
00704     { return _M_ios_locale; }
00705 
00706     // [27.4.2.5] ios_base storage functions
00707     /**
00708      *  @brief  Access to unique indices.
00709      *  @return  An integer different from all previous calls.
00710      *
00711      *  This function returns a unique integer every time it is called.  It
00712      *  can be used for any purpose, but is primarily intended to be a unique
00713      *  index for the iword and pword functions.  The expectation is that an
00714      *  application calls xalloc in order to obtain an index in the iword and
00715      *  pword arrays that can be used without fear of conflict.
00716      *
00717      *  The implementation maintains a static variable that is incremented and
00718      *  returned on each invocation.  xalloc is guaranteed to return an index
00719      *  that is safe to use in the iword and pword arrays.
00720     */
00721     static int
00722     xalloc() throw();
00723 
00724     /**
00725      *  @brief  Access to integer array.
00726      *  @param  __ix  Index into the array.
00727      *  @return  A reference to an integer associated with the index.
00728      *
00729      *  The iword function provides access to an array of integers that can be
00730      *  used for any purpose.  The array grows as required to hold the
00731      *  supplied index.  All integers in the array are initialized to 0.
00732      *
00733      *  The implementation reserves several indices.  You should use xalloc to
00734      *  obtain an index that is safe to use.  Also note that since the array
00735      *  can grow dynamically, it is not safe to hold onto the reference.
00736     */
00737     long&
00738     iword(int __ix)
00739     {
00740       _Words& __word = (__ix < _M_word_size)
00741             ? _M_word[__ix] : _M_grow_words(__ix, true);
00742       return __word._M_iword;
00743     }
00744 
00745     /**
00746      *  @brief  Access to void pointer array.
00747      *  @param  __ix  Index into the array.
00748      *  @return  A reference to a void* associated with the index.
00749      *
00750      *  The pword function provides access to an array of pointers that can be
00751      *  used for any purpose.  The array grows as required to hold the
00752      *  supplied index.  All pointers in the array are initialized to 0.
00753      *
00754      *  The implementation reserves several indices.  You should use xalloc to
00755      *  obtain an index that is safe to use.  Also note that since the array
00756      *  can grow dynamically, it is not safe to hold onto the reference.
00757     */
00758     void*&
00759     pword(int __ix)
00760     {
00761       _Words& __word = (__ix < _M_word_size)
00762             ? _M_word[__ix] : _M_grow_words(__ix, false);
00763       return __word._M_pword;
00764     }
00765 
00766     // Destructor
00767     /**
00768      *  Invokes each callback with erase_event.  Destroys local storage.
00769      *
00770      *  Note that the ios_base object for the standard streams never gets
00771      *  destroyed.  As a result, any callbacks registered with the standard
00772      *  streams will not get invoked with erase_event (unless copyfmt is
00773      *  used).
00774     */
00775     virtual ~ios_base();
00776 
00777   protected:
00778     ios_base();
00779 
00780   // _GLIBCXX_RESOLVE_LIB_DEFECTS
00781   // 50.  Copy constructor and assignment operator of ios_base
00782   private:
00783     ios_base(const ios_base&);
00784 
00785     ios_base&
00786     operator=(const ios_base&);
00787   };
00788 
00789   // [27.4.5.1] fmtflags manipulators
00790   /// Calls base.setf(ios_base::boolalpha).
00791   inline ios_base&
00792   boolalpha(ios_base& __base)
00793   {
00794     __base.setf(ios_base::boolalpha);
00795     return __base;
00796   }
00797 
00798   /// Calls base.unsetf(ios_base::boolalpha).
00799   inline ios_base&
00800   noboolalpha(ios_base& __base)
00801   {
00802     __base.unsetf(ios_base::boolalpha);
00803     return __base;
00804   }
00805 
00806   /// Calls base.setf(ios_base::showbase).
00807   inline ios_base&
00808   showbase(ios_base& __base)
00809   {
00810     __base.setf(ios_base::showbase);
00811     return __base;
00812   }
00813 
00814   /// Calls base.unsetf(ios_base::showbase).
00815   inline ios_base&
00816   noshowbase(ios_base& __base)
00817   {
00818     __base.unsetf(ios_base::showbase);
00819     return __base;
00820   }
00821 
00822   /// Calls base.setf(ios_base::showpoint).
00823   inline ios_base&
00824   showpoint(ios_base& __base)
00825   {
00826     __base.setf(ios_base::showpoint);
00827     return __base;
00828   }
00829 
00830   /// Calls base.unsetf(ios_base::showpoint).
00831   inline ios_base&
00832   noshowpoint(ios_base& __base)
00833   {
00834     __base.unsetf(ios_base::showpoint);
00835     return __base;
00836   }
00837 
00838   /// Calls base.setf(ios_base::showpos).
00839   inline ios_base&
00840   showpos(ios_base& __base)
00841   {
00842     __base.setf(ios_base::showpos);
00843     return __base;
00844   }
00845 
00846   /// Calls base.unsetf(ios_base::showpos).
00847   inline ios_base&
00848   noshowpos(ios_base& __base)
00849   {
00850     __base.unsetf(ios_base::showpos);
00851     return __base;
00852   }
00853 
00854   /// Calls base.setf(ios_base::skipws).
00855   inline ios_base&
00856   skipws(ios_base& __base)
00857   {
00858     __base.setf(ios_base::skipws);
00859     return __base;
00860   }
00861 
00862   /// Calls base.unsetf(ios_base::skipws).
00863   inline ios_base&
00864   noskipws(ios_base& __base)
00865   {
00866     __base.unsetf(ios_base::skipws);
00867     return __base;
00868   }
00869 
00870   /// Calls base.setf(ios_base::uppercase).
00871   inline ios_base&
00872   uppercase(ios_base& __base)
00873   {
00874     __base.setf(ios_base::uppercase);
00875     return __base;
00876   }
00877 
00878   /// Calls base.unsetf(ios_base::uppercase).
00879   inline ios_base&
00880   nouppercase(ios_base& __base)
00881   {
00882     __base.unsetf(ios_base::uppercase);
00883     return __base;
00884   }
00885 
00886   /// Calls base.setf(ios_base::unitbuf).
00887   inline ios_base&
00888   unitbuf(ios_base& __base)
00889   {
00890      __base.setf(ios_base::unitbuf);
00891      return __base;
00892   }
00893 
00894   /// Calls base.unsetf(ios_base::unitbuf).
00895   inline ios_base&
00896   nounitbuf(ios_base& __base)
00897   {
00898      __base.unsetf(ios_base::unitbuf);
00899      return __base;
00900   }
00901 
00902   // [27.4.5.2] adjustfield manipulators
00903   /// Calls base.setf(ios_base::internal, ios_base::adjustfield).
00904   inline ios_base&
00905   internal(ios_base& __base)
00906   {
00907      __base.setf(ios_base::internal, ios_base::adjustfield);
00908      return __base;
00909   }
00910 
00911   /// Calls base.setf(ios_base::left, ios_base::adjustfield).
00912   inline ios_base&
00913   left(ios_base& __base)
00914   {
00915     __base.setf(ios_base::left, ios_base::adjustfield);
00916     return __base;
00917   }
00918 
00919   /// Calls base.setf(ios_base::right, ios_base::adjustfield).
00920   inline ios_base&
00921   right(ios_base& __base)
00922   {
00923     __base.setf(ios_base::right, ios_base::adjustfield);
00924     return __base;
00925   }
00926 
00927   // [27.4.5.3] basefield manipulators
00928   /// Calls base.setf(ios_base::dec, ios_base::basefield).
00929   inline ios_base&
00930   dec(ios_base& __base)
00931   {
00932     __base.setf(ios_base::dec, ios_base::basefield);
00933     return __base;
00934   }
00935 
00936   /// Calls base.setf(ios_base::hex, ios_base::basefield).
00937   inline ios_base&
00938   hex(ios_base& __base)
00939   {
00940     __base.setf(ios_base::hex, ios_base::basefield);
00941     return __base;
00942   }
00943 
00944   /// Calls base.setf(ios_base::oct, ios_base::basefield).
00945   inline ios_base&
00946   oct(ios_base& __base)
00947   {
00948     __base.setf(ios_base::oct, ios_base::basefield);
00949     return __base;
00950   }
00951 
00952   // [27.4.5.4] floatfield manipulators
00953   /// Calls base.setf(ios_base::fixed, ios_base::floatfield).
00954   inline ios_base&
00955   fixed(ios_base& __base)
00956   {
00957     __base.setf(ios_base::fixed, ios_base::floatfield);
00958     return __base;
00959   }
00960 
00961   /// Calls base.setf(ios_base::scientific, ios_base::floatfield).
00962   inline ios_base&
00963   scientific(ios_base& __base)
00964   {
00965     __base.setf(ios_base::scientific, ios_base::floatfield);
00966     return __base;
00967   }
00968 
00969 _GLIBCXX_END_NAMESPACE
00970 
00971 #endif /* _IOS_BASE_H */
00972 

Generated on Wed Mar 26 00:42:58 2008 for libstdc++ by  doxygen 1.5.1