libstdc++
ios_base.h
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1 // Iostreams base classes -*- C++ -*-
2 
3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
4 // 2006, 2007, 2008, 2009, 2010
5 // Free Software Foundation, Inc.
6 //
7 // This file is part of the GNU ISO C++ Library. This library is free
8 // software; you can redistribute it and/or modify it under the
9 // terms of the GNU General Public License as published by the
10 // Free Software Foundation; either version 3, or (at your option)
11 // any later version.
12 
13 // This library is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 // GNU General Public License for more details.
17 
18 // Under Section 7 of GPL version 3, you are granted additional
19 // permissions described in the GCC Runtime Library Exception, version
20 // 3.1, as published by the Free Software Foundation.
21 
22 // You should have received a copy of the GNU General Public License and
23 // a copy of the GCC Runtime Library Exception along with this program;
24 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
25 // <http://www.gnu.org/licenses/>.
26 
27 /** @file bits/ios_base.h
28  * This is an internal header file, included by other library headers.
29  * Do not attempt to use it directly. @headername{ios}
30  */
31 
32 //
33 // ISO C++ 14882: 27.4 Iostreams base classes
34 //
35 
36 #ifndef _IOS_BASE_H
37 #define _IOS_BASE_H 1
38 
39 #pragma GCC system_header
40 
41 #include <ext/atomicity.h>
42 #include <bits/localefwd.h>
43 #include <bits/locale_classes.h>
44 
45 namespace std _GLIBCXX_VISIBILITY(default)
46 {
47 _GLIBCXX_BEGIN_NAMESPACE_VERSION
48 
49  // The following definitions of bitmask types are enums, not ints,
50  // as permitted (but not required) in the standard, in order to provide
51  // better type safety in iostream calls. A side effect is that
52  // expressions involving them are no longer compile-time constants.
53  enum _Ios_Fmtflags
54  {
55  _S_boolalpha = 1L << 0,
56  _S_dec = 1L << 1,
57  _S_fixed = 1L << 2,
58  _S_hex = 1L << 3,
59  _S_internal = 1L << 4,
60  _S_left = 1L << 5,
61  _S_oct = 1L << 6,
62  _S_right = 1L << 7,
63  _S_scientific = 1L << 8,
64  _S_showbase = 1L << 9,
65  _S_showpoint = 1L << 10,
66  _S_showpos = 1L << 11,
67  _S_skipws = 1L << 12,
68  _S_unitbuf = 1L << 13,
69  _S_uppercase = 1L << 14,
70  _S_adjustfield = _S_left | _S_right | _S_internal,
71  _S_basefield = _S_dec | _S_oct | _S_hex,
72  _S_floatfield = _S_scientific | _S_fixed,
73  _S_ios_fmtflags_end = 1L << 16
74  };
75 
76  inline _GLIBCXX_CONSTEXPR _Ios_Fmtflags
77  operator&(_Ios_Fmtflags __a, _Ios_Fmtflags __b)
78  { return _Ios_Fmtflags(static_cast<int>(__a) & static_cast<int>(__b)); }
79 
80  inline _GLIBCXX_CONSTEXPR _Ios_Fmtflags
81  operator|(_Ios_Fmtflags __a, _Ios_Fmtflags __b)
82  { return _Ios_Fmtflags(static_cast<int>(__a) | static_cast<int>(__b)); }
83 
84  inline _GLIBCXX_CONSTEXPR _Ios_Fmtflags
85  operator^(_Ios_Fmtflags __a, _Ios_Fmtflags __b)
86  { return _Ios_Fmtflags(static_cast<int>(__a) ^ static_cast<int>(__b)); }
87 
88  inline _GLIBCXX_CONSTEXPR _Ios_Fmtflags
89  operator~(_Ios_Fmtflags __a)
90  { return _Ios_Fmtflags(~static_cast<int>(__a)); }
91 
92  inline const _Ios_Fmtflags&
93  operator|=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b)
94  { return __a = __a | __b; }
95 
96  inline const _Ios_Fmtflags&
97  operator&=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b)
98  { return __a = __a & __b; }
99 
100  inline const _Ios_Fmtflags&
101  operator^=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b)
102  { return __a = __a ^ __b; }
103 
104 
105  enum _Ios_Openmode
106  {
107  _S_app = 1L << 0,
108  _S_ate = 1L << 1,
109  _S_bin = 1L << 2,
110  _S_in = 1L << 3,
111  _S_out = 1L << 4,
112  _S_trunc = 1L << 5,
113  _S_ios_openmode_end = 1L << 16
114  };
115 
116  inline _GLIBCXX_CONSTEXPR _Ios_Openmode
117  operator&(_Ios_Openmode __a, _Ios_Openmode __b)
118  { return _Ios_Openmode(static_cast<int>(__a) & static_cast<int>(__b)); }
119 
120  inline _GLIBCXX_CONSTEXPR _Ios_Openmode
121  operator|(_Ios_Openmode __a, _Ios_Openmode __b)
122  { return _Ios_Openmode(static_cast<int>(__a) | static_cast<int>(__b)); }
123 
124  inline _GLIBCXX_CONSTEXPR _Ios_Openmode
125  operator^(_Ios_Openmode __a, _Ios_Openmode __b)
126  { return _Ios_Openmode(static_cast<int>(__a) ^ static_cast<int>(__b)); }
127 
128  inline _GLIBCXX_CONSTEXPR _Ios_Openmode
129  operator~(_Ios_Openmode __a)
130  { return _Ios_Openmode(~static_cast<int>(__a)); }
131 
132  inline const _Ios_Openmode&
133  operator|=(_Ios_Openmode& __a, _Ios_Openmode __b)
134  { return __a = __a | __b; }
135 
136  inline const _Ios_Openmode&
137  operator&=(_Ios_Openmode& __a, _Ios_Openmode __b)
138  { return __a = __a & __b; }
139 
140  inline const _Ios_Openmode&
141  operator^=(_Ios_Openmode& __a, _Ios_Openmode __b)
142  { return __a = __a ^ __b; }
143 
144 
145  enum _Ios_Iostate
146  {
147  _S_goodbit = 0,
148  _S_badbit = 1L << 0,
149  _S_eofbit = 1L << 1,
150  _S_failbit = 1L << 2,
151  _S_ios_iostate_end = 1L << 16
152  };
153 
154  inline _GLIBCXX_CONSTEXPR _Ios_Iostate
155  operator&(_Ios_Iostate __a, _Ios_Iostate __b)
156  { return _Ios_Iostate(static_cast<int>(__a) & static_cast<int>(__b)); }
157 
158  inline _GLIBCXX_CONSTEXPR _Ios_Iostate
159  operator|(_Ios_Iostate __a, _Ios_Iostate __b)
160  { return _Ios_Iostate(static_cast<int>(__a) | static_cast<int>(__b)); }
161 
162  inline _GLIBCXX_CONSTEXPR _Ios_Iostate
163  operator^(_Ios_Iostate __a, _Ios_Iostate __b)
164  { return _Ios_Iostate(static_cast<int>(__a) ^ static_cast<int>(__b)); }
165 
166  inline _GLIBCXX_CONSTEXPR _Ios_Iostate
167  operator~(_Ios_Iostate __a)
168  { return _Ios_Iostate(~static_cast<int>(__a)); }
169 
170  inline const _Ios_Iostate&
171  operator|=(_Ios_Iostate& __a, _Ios_Iostate __b)
172  { return __a = __a | __b; }
173 
174  inline const _Ios_Iostate&
175  operator&=(_Ios_Iostate& __a, _Ios_Iostate __b)
176  { return __a = __a & __b; }
177 
178  inline const _Ios_Iostate&
179  operator^=(_Ios_Iostate& __a, _Ios_Iostate __b)
180  { return __a = __a ^ __b; }
181 
182 
183  enum _Ios_Seekdir
184  {
185  _S_beg = 0,
186  _S_cur = _GLIBCXX_STDIO_SEEK_CUR,
187  _S_end = _GLIBCXX_STDIO_SEEK_END,
188  _S_ios_seekdir_end = 1L << 16
189  };
190 
191  // 27.4.2 Class ios_base
192  /**
193  * @brief The base of the I/O class hierarchy.
194  * @ingroup io
195  *
196  * This class defines everything that can be defined about I/O that does
197  * not depend on the type of characters being input or output. Most
198  * people will only see @c ios_base when they need to specify the full
199  * name of the various I/O flags (e.g., the openmodes).
200  */
201  class ios_base
202  {
203  public:
204 
205  /**
206  * @brief These are thrown to indicate problems with io.
207  * @ingroup exceptions
208  *
209  * 27.4.2.1.1 Class ios_base::failure
210  */
211  class failure : public exception
212  {
213  public:
214  // _GLIBCXX_RESOLVE_LIB_DEFECTS
215  // 48. Use of non-existent exception constructor
216  explicit
217  failure(const string& __str) throw();
218 
219  // This declaration is not useless:
220  // http://gcc.gnu.org/onlinedocs/gcc-4.3.2/gcc/Vague-Linkage.html
221  virtual
222  ~failure() throw();
223 
224  virtual const char*
225  what() const throw();
226 
227  private:
228  string _M_msg;
229  };
230 
231  // 27.4.2.1.2 Type ios_base::fmtflags
232  /**
233  * @brief This is a bitmask type.
234  *
235  * @c @a _Ios_Fmtflags is implementation-defined, but it is valid to
236  * perform bitwise operations on these values and expect the Right
237  * Thing to happen. Defined objects of type fmtflags are:
238  * - boolalpha
239  * - dec
240  * - fixed
241  * - hex
242  * - internal
243  * - left
244  * - oct
245  * - right
246  * - scientific
247  * - showbase
248  * - showpoint
249  * - showpos
250  * - skipws
251  * - unitbuf
252  * - uppercase
253  * - adjustfield
254  * - basefield
255  * - floatfield
256  */
257  typedef _Ios_Fmtflags fmtflags;
258 
259  /// Insert/extract @c bool in alphabetic rather than numeric format.
260  static const fmtflags boolalpha = _S_boolalpha;
261 
262  /// Converts integer input or generates integer output in decimal base.
263  static const fmtflags dec = _S_dec;
264 
265  /// Generate floating-point output in fixed-point notation.
266  static const fmtflags fixed = _S_fixed;
267 
268  /// Converts integer input or generates integer output in hexadecimal base.
269  static const fmtflags hex = _S_hex;
270 
271  /// Adds fill characters at a designated internal point in certain
272  /// generated output, or identical to @c right if no such point is
273  /// designated.
274  static const fmtflags internal = _S_internal;
275 
276  /// Adds fill characters on the right (final positions) of certain
277  /// generated output. (I.e., the thing you print is flush left.)
278  static const fmtflags left = _S_left;
279 
280  /// Converts integer input or generates integer output in octal base.
281  static const fmtflags oct = _S_oct;
282 
283  /// Adds fill characters on the left (initial positions) of certain
284  /// generated output. (I.e., the thing you print is flush right.)
285  static const fmtflags right = _S_right;
286 
287  /// Generates floating-point output in scientific notation.
288  static const fmtflags scientific = _S_scientific;
289 
290  /// Generates a prefix indicating the numeric base of generated integer
291  /// output.
292  static const fmtflags showbase = _S_showbase;
293 
294  /// Generates a decimal-point character unconditionally in generated
295  /// floating-point output.
296  static const fmtflags showpoint = _S_showpoint;
297 
298  /// Generates a + sign in non-negative generated numeric output.
299  static const fmtflags showpos = _S_showpos;
300 
301  /// Skips leading white space before certain input operations.
302  static const fmtflags skipws = _S_skipws;
303 
304  /// Flushes output after each output operation.
305  static const fmtflags unitbuf = _S_unitbuf;
306 
307  /// Replaces certain lowercase letters with their uppercase equivalents
308  /// in generated output.
309  static const fmtflags uppercase = _S_uppercase;
310 
311  /// A mask of left|right|internal. Useful for the 2-arg form of @c setf.
312  static const fmtflags adjustfield = _S_adjustfield;
313 
314  /// A mask of dec|oct|hex. Useful for the 2-arg form of @c setf.
315  static const fmtflags basefield = _S_basefield;
316 
317  /// A mask of scientific|fixed. Useful for the 2-arg form of @c setf.
318  static const fmtflags floatfield = _S_floatfield;
319 
320  // 27.4.2.1.3 Type ios_base::iostate
321  /**
322  * @brief This is a bitmask type.
323  *
324  * @c @a _Ios_Iostate is implementation-defined, but it is valid to
325  * perform bitwise operations on these values and expect the Right
326  * Thing to happen. Defined objects of type iostate are:
327  * - badbit
328  * - eofbit
329  * - failbit
330  * - goodbit
331  */
332  typedef _Ios_Iostate iostate;
333 
334  /// Indicates a loss of integrity in an input or output sequence (such
335  /// as an irrecoverable read error from a file).
336  static const iostate badbit = _S_badbit;
337 
338  /// Indicates that an input operation reached the end of an input sequence.
339  static const iostate eofbit = _S_eofbit;
340 
341  /// Indicates that an input operation failed to read the expected
342  /// characters, or that an output operation failed to generate the
343  /// desired characters.
344  static const iostate failbit = _S_failbit;
345 
346  /// Indicates all is well.
347  static const iostate goodbit = _S_goodbit;
348 
349  // 27.4.2.1.4 Type ios_base::openmode
350  /**
351  * @brief This is a bitmask type.
352  *
353  * @c @a _Ios_Openmode is implementation-defined, but it is valid to
354  * perform bitwise operations on these values and expect the Right
355  * Thing to happen. Defined objects of type openmode are:
356  * - app
357  * - ate
358  * - binary
359  * - in
360  * - out
361  * - trunc
362  */
363  typedef _Ios_Openmode openmode;
364 
365  /// Seek to end before each write.
366  static const openmode app = _S_app;
367 
368  /// Open and seek to end immediately after opening.
369  static const openmode ate = _S_ate;
370 
371  /// Perform input and output in binary mode (as opposed to text mode).
372  /// This is probably not what you think it is; see
373  /// http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt11ch27s02.html
374  static const openmode binary = _S_bin;
375 
376  /// Open for input. Default for @c ifstream and fstream.
377  static const openmode in = _S_in;
378 
379  /// Open for output. Default for @c ofstream and fstream.
380  static const openmode out = _S_out;
381 
382  /// Open for input. Default for @c ofstream.
383  static const openmode trunc = _S_trunc;
384 
385  // 27.4.2.1.5 Type ios_base::seekdir
386  /**
387  * @brief This is an enumerated type.
388  *
389  * @c @a _Ios_Seekdir is implementation-defined. Defined values
390  * of type seekdir are:
391  * - beg
392  * - cur, equivalent to @c SEEK_CUR in the C standard library.
393  * - end, equivalent to @c SEEK_END in the C standard library.
394  */
395  typedef _Ios_Seekdir seekdir;
396 
397  /// Request a seek relative to the beginning of the stream.
398  static const seekdir beg = _S_beg;
399 
400  /// Request a seek relative to the current position within the sequence.
401  static const seekdir cur = _S_cur;
402 
403  /// Request a seek relative to the current end of the sequence.
404  static const seekdir end = _S_end;
405 
406  // Annex D.6
407  typedef int io_state;
408  typedef int open_mode;
409  typedef int seek_dir;
410 
411  typedef std::streampos streampos;
412  typedef std::streamoff streamoff;
413 
414  // Callbacks;
415  /**
416  * @brief The set of events that may be passed to an event callback.
417  *
418  * erase_event is used during ~ios() and copyfmt(). imbue_event is used
419  * during imbue(). copyfmt_event is used during copyfmt().
420  */
421  enum event
422  {
423  erase_event,
424  imbue_event,
425  copyfmt_event
426  };
427 
428  /**
429  * @brief The type of an event callback function.
430  * @param event One of the members of the event enum.
431  * @param ios_base Reference to the ios_base object.
432  * @param int The integer provided when the callback was registered.
433  *
434  * Event callbacks are user defined functions that get called during
435  * several ios_base and basic_ios functions, specifically imbue(),
436  * copyfmt(), and ~ios().
437  */
438  typedef void (*event_callback) (event, ios_base&, int);
439 
440  /**
441  * @brief Add the callback __fn with parameter __index.
442  * @param __fn The function to add.
443  * @param __index The integer to pass to the function when invoked.
444  *
445  * Registers a function as an event callback with an integer parameter to
446  * be passed to the function when invoked. Multiple copies of the
447  * function are allowed. If there are multiple callbacks, they are
448  * invoked in the order they were registered.
449  */
450  void
451  register_callback(event_callback __fn, int __index);
452 
453  protected:
454  streamsize _M_precision;
455  streamsize _M_width;
456  fmtflags _M_flags;
457  iostate _M_exception;
458  iostate _M_streambuf_state;
459 
460  // 27.4.2.6 Members for callbacks
461  // 27.4.2.6 ios_base callbacks
462  struct _Callback_list
463  {
464  // Data Members
465  _Callback_list* _M_next;
467  int _M_index;
468  _Atomic_word _M_refcount; // 0 means one reference.
469 
470  _Callback_list(ios_base::event_callback __fn, int __index,
471  _Callback_list* __cb)
472  : _M_next(__cb), _M_fn(__fn), _M_index(__index), _M_refcount(0) { }
473 
474  void
475  _M_add_reference() { __gnu_cxx::__atomic_add_dispatch(&_M_refcount, 1); }
476 
477  // 0 => OK to delete.
478  int
479  _M_remove_reference()
480  {
481  // Be race-detector-friendly. For more info see bits/c++config.
482  _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&_M_refcount);
483  int __res = __gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1);
484  if (__res == 0)
485  {
486  _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&_M_refcount);
487  }
488  return __res;
489  }
490  };
491 
492  _Callback_list* _M_callbacks;
493 
494  void
495  _M_call_callbacks(event __ev) throw();
496 
497  void
498  _M_dispose_callbacks(void) throw();
499 
500  // 27.4.2.5 Members for iword/pword storage
501  struct _Words
502  {
503  void* _M_pword;
504  long _M_iword;
505  _Words() : _M_pword(0), _M_iword(0) { }
506  };
507 
508  // Only for failed iword/pword calls.
509  _Words _M_word_zero;
510 
511  // Guaranteed storage.
512  // The first 5 iword and pword slots are reserved for internal use.
513  enum { _S_local_word_size = 8 };
514  _Words _M_local_word[_S_local_word_size];
515 
516  // Allocated storage.
517  int _M_word_size;
518  _Words* _M_word;
519 
520  _Words&
521  _M_grow_words(int __index, bool __iword);
522 
523  // Members for locale and locale caching.
524  locale _M_ios_locale;
525 
526  void
527  _M_init() throw();
528 
529  public:
530 
531  // 27.4.2.1.6 Class ios_base::Init
532  // Used to initialize standard streams. In theory, g++ could use
533  // -finit-priority to order this stuff correctly without going
534  // through these machinations.
535  class Init
536  {
537  friend class ios_base;
538  public:
539  Init();
540  ~Init();
541 
542  private:
543  static _Atomic_word _S_refcount;
544  static bool _S_synced_with_stdio;
545  };
546 
547  // [27.4.2.2] fmtflags state functions
548  /**
549  * @brief Access to format flags.
550  * @return The format control flags for both input and output.
551  */
552  fmtflags
553  flags() const
554  { return _M_flags; }
555 
556  /**
557  * @brief Setting new format flags all at once.
558  * @param fmtfl The new flags to set.
559  * @return The previous format control flags.
560  *
561  * This function overwrites all the format flags with @a fmtfl.
562  */
563  fmtflags
564  flags(fmtflags __fmtfl)
565  {
566  fmtflags __old = _M_flags;
567  _M_flags = __fmtfl;
568  return __old;
569  }
570 
571  /**
572  * @brief Setting new format flags.
573  * @param fmtfl Additional flags to set.
574  * @return The previous format control flags.
575  *
576  * This function sets additional flags in format control. Flags that
577  * were previously set remain set.
578  */
579  fmtflags
580  setf(fmtflags __fmtfl)
581  {
582  fmtflags __old = _M_flags;
583  _M_flags |= __fmtfl;
584  return __old;
585  }
586 
587  /**
588  * @brief Setting new format flags.
589  * @param fmtfl Additional flags to set.
590  * @param mask The flags mask for @a fmtfl.
591  * @return The previous format control flags.
592  *
593  * This function clears @a mask in the format flags, then sets
594  * @a fmtfl @c & @a mask. An example mask is @c ios_base::adjustfield.
595  */
596  fmtflags
597  setf(fmtflags __fmtfl, fmtflags __mask)
598  {
599  fmtflags __old = _M_flags;
600  _M_flags &= ~__mask;
601  _M_flags |= (__fmtfl & __mask);
602  return __old;
603  }
604 
605  /**
606  * @brief Clearing format flags.
607  * @param mask The flags to unset.
608  *
609  * This function clears @a mask in the format flags.
610  */
611  void
612  unsetf(fmtflags __mask)
613  { _M_flags &= ~__mask; }
614 
615  /**
616  * @brief Flags access.
617  * @return The precision to generate on certain output operations.
618  *
619  * Be careful if you try to give a definition of @a precision here; see
620  * DR 189.
621  */
622  streamsize
623  precision() const
624  { return _M_precision; }
625 
626  /**
627  * @brief Changing flags.
628  * @param prec The new precision value.
629  * @return The previous value of precision().
630  */
631  streamsize
633  {
634  streamsize __old = _M_precision;
635  _M_precision = __prec;
636  return __old;
637  }
638 
639  /**
640  * @brief Flags access.
641  * @return The minimum field width to generate on output operations.
642  *
643  * <em>Minimum field width</em> refers to the number of characters.
644  */
645  streamsize
646  width() const
647  { return _M_width; }
648 
649  /**
650  * @brief Changing flags.
651  * @param wide The new width value.
652  * @return The previous value of width().
653  */
654  streamsize
656  {
657  streamsize __old = _M_width;
658  _M_width = __wide;
659  return __old;
660  }
661 
662  // [27.4.2.4] ios_base static members
663  /**
664  * @brief Interaction with the standard C I/O objects.
665  * @param sync Whether to synchronize or not.
666  * @return True if the standard streams were previously synchronized.
667  *
668  * The synchronization referred to is @e only that between the standard
669  * C facilities (e.g., stdout) and the standard C++ objects (e.g.,
670  * cout). User-declared streams are unaffected. See
671  * http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt11ch28s02.html
672  */
673  static bool
674  sync_with_stdio(bool __sync = true);
675 
676  // [27.4.2.3] ios_base locale functions
677  /**
678  * @brief Setting a new locale.
679  * @param loc The new locale.
680  * @return The previous locale.
681  *
682  * Sets the new locale for this stream, and then invokes each callback
683  * with imbue_event.
684  */
685  locale
686  imbue(const locale& __loc) throw();
687 
688  /**
689  * @brief Locale access
690  * @return A copy of the current locale.
691  *
692  * If @c imbue(loc) has previously been called, then this function
693  * returns @c loc. Otherwise, it returns a copy of @c std::locale(),
694  * the global C++ locale.
695  */
696  locale
697  getloc() const
698  { return _M_ios_locale; }
699 
700  /**
701  * @brief Locale access
702  * @return A reference to the current locale.
703  *
704  * Like getloc above, but returns a reference instead of
705  * generating a copy.
706  */
707  const locale&
708  _M_getloc() const
709  { return _M_ios_locale; }
710 
711  // [27.4.2.5] ios_base storage functions
712  /**
713  * @brief Access to unique indices.
714  * @return An integer different from all previous calls.
715  *
716  * This function returns a unique integer every time it is called. It
717  * can be used for any purpose, but is primarily intended to be a unique
718  * index for the iword and pword functions. The expectation is that an
719  * application calls xalloc in order to obtain an index in the iword and
720  * pword arrays that can be used without fear of conflict.
721  *
722  * The implementation maintains a static variable that is incremented and
723  * returned on each invocation. xalloc is guaranteed to return an index
724  * that is safe to use in the iword and pword arrays.
725  */
726  static int
727  xalloc() throw();
728 
729  /**
730  * @brief Access to integer array.
731  * @param __ix Index into the array.
732  * @return A reference to an integer associated with the index.
733  *
734  * The iword function provides access to an array of integers that can be
735  * used for any purpose. The array grows as required to hold the
736  * supplied index. All integers in the array are initialized to 0.
737  *
738  * The implementation reserves several indices. You should use xalloc to
739  * obtain an index that is safe to use. Also note that since the array
740  * can grow dynamically, it is not safe to hold onto the reference.
741  */
742  long&
743  iword(int __ix)
744  {
745  _Words& __word = (__ix < _M_word_size)
746  ? _M_word[__ix] : _M_grow_words(__ix, true);
747  return __word._M_iword;
748  }
749 
750  /**
751  * @brief Access to void pointer array.
752  * @param __ix Index into the array.
753  * @return A reference to a void* associated with the index.
754  *
755  * The pword function provides access to an array of pointers that can be
756  * used for any purpose. The array grows as required to hold the
757  * supplied index. All pointers in the array are initialized to 0.
758  *
759  * The implementation reserves several indices. You should use xalloc to
760  * obtain an index that is safe to use. Also note that since the array
761  * can grow dynamically, it is not safe to hold onto the reference.
762  */
763  void*&
764  pword(int __ix)
765  {
766  _Words& __word = (__ix < _M_word_size)
767  ? _M_word[__ix] : _M_grow_words(__ix, false);
768  return __word._M_pword;
769  }
770 
771  // Destructor
772  /**
773  * Invokes each callback with erase_event. Destroys local storage.
774  *
775  * Note that the ios_base object for the standard streams never gets
776  * destroyed. As a result, any callbacks registered with the standard
777  * streams will not get invoked with erase_event (unless copyfmt is
778  * used).
779  */
780  virtual ~ios_base();
781 
782  protected:
783  ios_base() throw ();
784 
785  // _GLIBCXX_RESOLVE_LIB_DEFECTS
786  // 50. Copy constructor and assignment operator of ios_base
787  private:
788  ios_base(const ios_base&);
789 
790  ios_base&
791  operator=(const ios_base&);
792  };
793 
794  // [27.4.5.1] fmtflags manipulators
795  /// Calls base.setf(ios_base::boolalpha).
796  inline ios_base&
797  boolalpha(ios_base& __base)
798  {
799  __base.setf(ios_base::boolalpha);
800  return __base;
801  }
802 
803  /// Calls base.unsetf(ios_base::boolalpha).
804  inline ios_base&
806  {
807  __base.unsetf(ios_base::boolalpha);
808  return __base;
809  }
810 
811  /// Calls base.setf(ios_base::showbase).
812  inline ios_base&
814  {
815  __base.setf(ios_base::showbase);
816  return __base;
817  }
818 
819  /// Calls base.unsetf(ios_base::showbase).
820  inline ios_base&
822  {
823  __base.unsetf(ios_base::showbase);
824  return __base;
825  }
826 
827  /// Calls base.setf(ios_base::showpoint).
828  inline ios_base&
830  {
831  __base.setf(ios_base::showpoint);
832  return __base;
833  }
834 
835  /// Calls base.unsetf(ios_base::showpoint).
836  inline ios_base&
838  {
839  __base.unsetf(ios_base::showpoint);
840  return __base;
841  }
842 
843  /// Calls base.setf(ios_base::showpos).
844  inline ios_base&
846  {
847  __base.setf(ios_base::showpos);
848  return __base;
849  }
850 
851  /// Calls base.unsetf(ios_base::showpos).
852  inline ios_base&
854  {
855  __base.unsetf(ios_base::showpos);
856  return __base;
857  }
858 
859  /// Calls base.setf(ios_base::skipws).
860  inline ios_base&
862  {
863  __base.setf(ios_base::skipws);
864  return __base;
865  }
866 
867  /// Calls base.unsetf(ios_base::skipws).
868  inline ios_base&
870  {
871  __base.unsetf(ios_base::skipws);
872  return __base;
873  }
874 
875  /// Calls base.setf(ios_base::uppercase).
876  inline ios_base&
878  {
879  __base.setf(ios_base::uppercase);
880  return __base;
881  }
882 
883  /// Calls base.unsetf(ios_base::uppercase).
884  inline ios_base&
886  {
887  __base.unsetf(ios_base::uppercase);
888  return __base;
889  }
890 
891  /// Calls base.setf(ios_base::unitbuf).
892  inline ios_base&
894  {
895  __base.setf(ios_base::unitbuf);
896  return __base;
897  }
898 
899  /// Calls base.unsetf(ios_base::unitbuf).
900  inline ios_base&
902  {
903  __base.unsetf(ios_base::unitbuf);
904  return __base;
905  }
906 
907  // [27.4.5.2] adjustfield manipulators
908  /// Calls base.setf(ios_base::internal, ios_base::adjustfield).
909  inline ios_base&
910  internal(ios_base& __base)
911  {
913  return __base;
914  }
915 
916  /// Calls base.setf(ios_base::left, ios_base::adjustfield).
917  inline ios_base&
919  {
921  return __base;
922  }
923 
924  /// Calls base.setf(ios_base::right, ios_base::adjustfield).
925  inline ios_base&
927  {
929  return __base;
930  }
931 
932  // [27.4.5.3] basefield manipulators
933  /// Calls base.setf(ios_base::dec, ios_base::basefield).
934  inline ios_base&
936  {
938  return __base;
939  }
940 
941  /// Calls base.setf(ios_base::hex, ios_base::basefield).
942  inline ios_base&
944  {
946  return __base;
947  }
948 
949  /// Calls base.setf(ios_base::oct, ios_base::basefield).
950  inline ios_base&
952  {
954  return __base;
955  }
956 
957  // [27.4.5.4] floatfield manipulators
958  /// Calls base.setf(ios_base::fixed, ios_base::floatfield).
959  inline ios_base&
961  {
963  return __base;
964  }
965 
966  /// Calls base.setf(ios_base::scientific, ios_base::floatfield).
967  inline ios_base&
969  {
971  return __base;
972  }
973 
974 _GLIBCXX_END_NAMESPACE_VERSION
975 } // namespace
976 
977 #endif /* _IOS_BASE_H */
static bool sync_with_stdio(bool __sync=true)
Interaction with the standard C I/O objects.
The base of the I/O class hierarchy.This class defines everything that can be defined about I/O that ...
Definition: ios_base.h:201
static const fmtflags scientific
Generates floating-point output in scientific notation.
Definition: ios_base.h:288
streamsize width(streamsize __wide)
Changing flags.
Definition: ios_base.h:655
static const iostate eofbit
Indicates that an input operation reached the end of an input sequence.
Definition: ios_base.h:339
streamsize width() const
Flags access.
Definition: ios_base.h:646
static const seekdir beg
Request a seek relative to the beginning of the stream.
Definition: ios_base.h:398
static const openmode binary
Perform input and output in binary mode (as opposed to text mode). This is probably not what you thin...
Definition: ios_base.h:374
ios_base & nounitbuf(ios_base &__base)
Calls base.unsetf(ios_base::unitbuf).
Definition: ios_base.h:901
static const fmtflags fixed
Generate floating-point output in fixed-point notation.
Definition: ios_base.h:266
ios_base & noboolalpha(ios_base &__base)
Calls base.unsetf(ios_base::boolalpha).
Definition: ios_base.h:805
long long streamoff
Type used by fpos, char_traits<char>, and char_traits<wchar_t>.
Definition: postypes.h:96
void(* event_callback)(event, ios_base &, int)
The type of an event callback function.
Definition: ios_base.h:438
static const fmtflags basefield
A mask of dec|oct|hex. Useful for the 2-arg form of setf.
Definition: ios_base.h:315
virtual const char * what() const
static const fmtflags internal
Adds fill characters at a designated internal point in certain generated output, or identical to righ...
Definition: ios_base.h:274
static const seekdir end
Request a seek relative to the current end of the sequence.
Definition: ios_base.h:404
fmtflags setf(fmtflags __fmtfl)
Setting new format flags.
Definition: ios_base.h:580
ptrdiff_t streamsize
Integral type for I/O operation counts and buffer sizes.
Definition: postypes.h:100
ios_base & noshowpoint(ios_base &__base)
Calls base.unsetf(ios_base::showpoint).
Definition: ios_base.h:837
streamsize precision() const
Flags access.
Definition: ios_base.h:623
static const fmtflags showpos
Generates a + sign in non-negative generated numeric output.
Definition: ios_base.h:299
Class representing stream positions.
Definition: postypes.h:114
static const iostate goodbit
Indicates all is well.
Definition: ios_base.h:347
static const openmode ate
Open and seek to end immediately after opening.
Definition: ios_base.h:369
_Siter_base< _Iterator >::iterator_type __base(_Iterator __it)
const locale & _M_getloc() const
Locale access.
Definition: ios_base.h:708
static const fmtflags showpoint
Generates a decimal-point character unconditionally in generated floating-point output.
Definition: ios_base.h:296
static const openmode app
Seek to end before each write.
Definition: ios_base.h:366
static const fmtflags oct
Converts integer input or generates integer output in octal base.
Definition: ios_base.h:281
static const openmode trunc
Open for input. Default for ofstream.
Definition: ios_base.h:383
static const fmtflags boolalpha
Insert/extract bool in alphabetic rather than numeric format.
Definition: ios_base.h:260
Container class for localization functionality.The locale class is first a class wrapper for C librar...
event
The set of events that may be passed to an event callback.
Definition: ios_base.h:421
locale imbue(const locale &__loc)
Setting a new locale.
long & iword(int __ix)
Access to integer array.
Definition: ios_base.h:743
void *& pword(int __ix)
Access to void pointer array.
Definition: ios_base.h:764
void unsetf(fmtflags __mask)
Clearing format flags.
Definition: ios_base.h:612
static const fmtflags left
Adds fill characters on the right (final positions) of certain generated output. (I.e., the thing you print is flush left.)
Definition: ios_base.h:278
static const openmode in
Open for input. Default for ifstream and fstream.
Definition: ios_base.h:377
static int xalloc()
Access to unique indices.
static const seekdir cur
Request a seek relative to the current position within the sequence.
Definition: ios_base.h:401
locale getloc() const
Locale access.
Definition: ios_base.h:697
static const fmtflags floatfield
A mask of scientific|fixed. Useful for the 2-arg form of setf.
Definition: ios_base.h:318
ios_base & noshowbase(ios_base &__base)
Calls base.unsetf(ios_base::showbase).
Definition: ios_base.h:821
static const fmtflags unitbuf
Flushes output after each output operation.
Definition: ios_base.h:305
ios_base & noskipws(ios_base &__base)
Calls base.unsetf(ios_base::skipws).
Definition: ios_base.h:869
static const fmtflags skipws
Skips leading white space before certain input operations.
Definition: ios_base.h:302
ios_base & noshowpos(ios_base &__base)
Calls base.unsetf(ios_base::showpos).
Definition: ios_base.h:853
These are thrown to indicate problems with io.27.4.2.1.1 Class ios_base::failure. ...
Definition: ios_base.h:211
static const iostate badbit
Indicates a loss of integrity in an input or output sequence (such as an irrecoverable read error fro...
Definition: ios_base.h:336
static const fmtflags uppercase
Replaces certain lowercase letters with their uppercase equivalents in generated output.
Definition: ios_base.h:309
bitset< _Nb > operator~() const
See the no-argument flip().
Definition: bitset:1119
static const fmtflags right
Adds fill characters on the left (initial positions) of certain generated output. (I...
Definition: ios_base.h:285
_Ios_Iostate iostate
This is a bitmask type.
Definition: ios_base.h:332
_Ios_Fmtflags fmtflags
This is a bitmask type.
Definition: ios_base.h:257
static const openmode out
Open for output. Default for ofstream and fstream.
Definition: ios_base.h:380
fmtflags flags() const
Access to format flags.
Definition: ios_base.h:553
fmtflags setf(fmtflags __fmtfl, fmtflags __mask)
Setting new format flags.
Definition: ios_base.h:597
static const fmtflags adjustfield
A mask of left|right|internal. Useful for the 2-arg form of setf.
Definition: ios_base.h:312
Base class for all library exceptions.
Definition: exception:61
bitset< _Nb > operator&(const bitset< _Nb > &__x, const bitset< _Nb > &__y)
Global bitwise operations on bitsets.
Definition: bitset:1409
bitset< _Nb > operator^(const bitset< _Nb > &__x, const bitset< _Nb > &__y)
Global bitwise operations on bitsets.
Definition: bitset:1427
void register_callback(event_callback __fn, int __index)
Add the callback __fn with parameter __index.
bitset< _Nb > operator|(const bitset< _Nb > &__x, const bitset< _Nb > &__y)
Global bitwise operations on bitsets.
Definition: bitset:1418
static const fmtflags showbase
Generates a prefix indicating the numeric base of generated integer output.
Definition: ios_base.h:292
virtual ~ios_base()
static const iostate failbit
Indicates that an input operation failed to read the expected characters, or that an output operation...
Definition: ios_base.h:344
ios_base & nouppercase(ios_base &__base)
Calls base.unsetf(ios_base::uppercase).
Definition: ios_base.h:885
_Ios_Seekdir seekdir
This is an enumerated type.
Definition: ios_base.h:395
static const fmtflags dec
Converts integer input or generates integer output in decimal base.
Definition: ios_base.h:263
_Ios_Openmode openmode
This is a bitmask type.
Definition: ios_base.h:363
streamsize precision(streamsize __prec)
Changing flags.
Definition: ios_base.h:632
static const fmtflags hex
Converts integer input or generates integer output in hexadecimal base.
Definition: ios_base.h:269
fmtflags flags(fmtflags __fmtfl)
Setting new format flags all at once.
Definition: ios_base.h:564