1// Iostreams base classes -*- C++ -*-
2
3// Copyright (C) 1997-2015 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/** @file bits/ios_base.h
26 * This is an internal header file, included by other library headers.
27 * Do not attempt to use it directly. @headername{ios}
28 */
29
30//
31// ISO C++ 14882: 27.4 Iostreams base classes
32//
33
34#ifndef _IOS_BASE_H
35#define _IOS_BASE_H 1
36
37#pragma GCC system_header
38
39#include <ext/atomicity.h>
40#include <bits/localefwd.h>
41#include <bits/locale_classes.h>
42
43#if __cplusplus < 201103L
44# include <stdexcept>
45#else
46# include <system_error>
47#endif
48
49namespace std _GLIBCXX_VISIBILITY(default)
50{
51_GLIBCXX_BEGIN_NAMESPACE_VERSION
52
53 // The following definitions of bitmask types are enums, not ints,
54 // as permitted (but not required) in the standard, in order to provide
55 // better type safety in iostream calls. A side effect is that
56 // expressions involving them are no longer compile-time constants.
57 enum _Ios_Fmtflags
58 {
59 _S_boolalpha = 1L << 0,
60 _S_dec = 1L << 1,
61 _S_fixed = 1L << 2,
62 _S_hex = 1L << 3,
63 _S_internal = 1L << 4,
64 _S_left = 1L << 5,
65 _S_oct = 1L << 6,
66 _S_right = 1L << 7,
67 _S_scientific = 1L << 8,
68 _S_showbase = 1L << 9,
69 _S_showpoint = 1L << 10,
70 _S_showpos = 1L << 11,
71 _S_skipws = 1L << 12,
72 _S_unitbuf = 1L << 13,
73 _S_uppercase = 1L << 14,
74 _S_adjustfield = _S_left | _S_right | _S_internal,
75 _S_basefield = _S_dec | _S_oct | _S_hex,
76 _S_floatfield = _S_scientific | _S_fixed,
77 _S_ios_fmtflags_end = 1L << 16,
78 _S_ios_fmtflags_max = __INT_MAX__,
79 _S_ios_fmtflags_min = ~__INT_MAX__
80 };
81
82 inline _GLIBCXX_CONSTEXPR _Ios_Fmtflags
83 operator&(_Ios_Fmtflags __a, _Ios_Fmtflags __b)
84 { return _Ios_Fmtflags(static_cast<int>(__a) & static_cast<int>(__b)); }
85
86 inline _GLIBCXX_CONSTEXPR _Ios_Fmtflags
87 operator|(_Ios_Fmtflags __a, _Ios_Fmtflags __b)
88 { return _Ios_Fmtflags(static_cast<int>(__a) | static_cast<int>(__b)); }
89
90 inline _GLIBCXX_CONSTEXPR _Ios_Fmtflags
91 operator^(_Ios_Fmtflags __a, _Ios_Fmtflags __b)
92 { return _Ios_Fmtflags(static_cast<int>(__a) ^ static_cast<int>(__b)); }
93
94 inline _GLIBCXX_CONSTEXPR _Ios_Fmtflags
95 operator~(_Ios_Fmtflags __a)
96 { return _Ios_Fmtflags(~static_cast<int>(__a)); }
97
98 inline const _Ios_Fmtflags&
99 operator|=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b)
100 { return __a = __a | __b; }
101
102 inline const _Ios_Fmtflags&
103 operator&=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b)
104 { return __a = __a & __b; }
105
106 inline const _Ios_Fmtflags&
107 operator^=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b)
108 { return __a = __a ^ __b; }
109
110
111 enum _Ios_Openmode
112 {
113 _S_app = 1L << 0,
114 _S_ate = 1L << 1,
115 _S_bin = 1L << 2,
116 _S_in = 1L << 3,
117 _S_out = 1L << 4,
118 _S_trunc = 1L << 5,
119 _S_ios_openmode_end = 1L << 16,
120 _S_ios_openmode_max = __INT_MAX__,
121 _S_ios_openmode_min = ~__INT_MAX__
122 };
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, _Ios_Openmode __b)
130 { return _Ios_Openmode(static_cast<int>(__a) | static_cast<int>(__b)); }
131
132 inline _GLIBCXX_CONSTEXPR _Ios_Openmode
133 operator^(_Ios_Openmode __a, _Ios_Openmode __b)
134 { return _Ios_Openmode(static_cast<int>(__a) ^ static_cast<int>(__b)); }
135
136 inline _GLIBCXX_CONSTEXPR _Ios_Openmode
137 operator~(_Ios_Openmode __a)
138 { return _Ios_Openmode(~static_cast<int>(__a)); }
139
140 inline const _Ios_Openmode&
141 operator|=(_Ios_Openmode& __a, _Ios_Openmode __b)
142 { return __a = __a | __b; }
143
144 inline const _Ios_Openmode&
145 operator&=(_Ios_Openmode& __a, _Ios_Openmode __b)
146 { return __a = __a & __b; }
147
148 inline const _Ios_Openmode&
149 operator^=(_Ios_Openmode& __a, _Ios_Openmode __b)
150 { return __a = __a ^ __b; }
151
152
153 enum _Ios_Iostate
154 {
155 _S_goodbit = 0,
156 _S_badbit = 1L << 0,
157 _S_eofbit = 1L << 1,
158 _S_failbit = 1L << 2,
159 _S_ios_iostate_end = 1L << 16,
160 _S_ios_iostate_max = __INT_MAX__,
161 _S_ios_iostate_min = ~__INT_MAX__
162 };
163
164 inline _GLIBCXX_CONSTEXPR _Ios_Iostate
165 operator&(_Ios_Iostate __a, _Ios_Iostate __b)
166 { return _Ios_Iostate(static_cast<int>(__a) & static_cast<int>(__b)); }
167
168 inline _GLIBCXX_CONSTEXPR _Ios_Iostate
169 operator|(_Ios_Iostate __a, _Ios_Iostate __b)
170 { return _Ios_Iostate(static_cast<int>(__a) | static_cast<int>(__b)); }
171
172 inline _GLIBCXX_CONSTEXPR _Ios_Iostate
173 operator^(_Ios_Iostate __a, _Ios_Iostate __b)
174 { return _Ios_Iostate(static_cast<int>(__a) ^ static_cast<int>(__b)); }
175
176 inline _GLIBCXX_CONSTEXPR _Ios_Iostate
177 operator~(_Ios_Iostate __a)
178 { return _Ios_Iostate(~static_cast<int>(__a)); }
179
180 inline const _Ios_Iostate&
181 operator|=(_Ios_Iostate& __a, _Ios_Iostate __b)
182 { return __a = __a | __b; }
183
184 inline const _Ios_Iostate&
185 operator&=(_Ios_Iostate& __a, _Ios_Iostate __b)
186 { return __a = __a & __b; }
187
188 inline const _Ios_Iostate&
189 operator^=(_Ios_Iostate& __a, _Ios_Iostate __b)
190 { return __a = __a ^ __b; }
191
192
193 enum _Ios_Seekdir
194 {
195 _S_beg = 0,
196 _S_cur = _GLIBCXX_STDIO_SEEK_CUR,
197 _S_end = _GLIBCXX_STDIO_SEEK_END,
198 _S_ios_seekdir_end = 1L << 16
199 };
200
201#if __cplusplus >= 201103L
202 /// I/O error code
203 enum class io_errc { stream = 1 };
204
205 template <> struct is_error_code_enum<io_errc> : public true_type { };
206
207 const error_category& iostream_category() noexcept;
208
209 inline error_code
210 make_error_code(io_errc e) noexcept
211 { return error_code(static_cast<int>(e), iostream_category()); }
212
213 inline error_condition
214 make_error_condition(io_errc e) noexcept
215 { return error_condition(static_cast<int>(e), iostream_category()); }
216#endif
217
218 // 27.4.2 Class ios_base
219 /**
220 * @brief The base of the I/O class hierarchy.
221 * @ingroup io
222 *
223 * This class defines everything that can be defined about I/O that does
224 * not depend on the type of characters being input or output. Most
225 * people will only see @c ios_base when they need to specify the full
226 * name of the various I/O flags (e.g., the openmodes).
227 */
228 class ios_base
229 {
230#if _GLIBCXX_USE_CXX11_ABI
231#if __cplusplus < 201103L
232 // Type that is layout-compatible with std::system_error
233 struct system_error : std::runtime_error
234 {
235 // Type that is layout-compatible with std::error_code
236 struct error_code
237 {
238 error_code() { }
239 private:
240 int _M_value;
241 const void* _M_cat;
242 } _M_code;
243 };
244#endif
245#endif
246 public:
247
248 /**
249 * @brief These are thrown to indicate problems with io.
250 * @ingroup exceptions
251 *
252 * 27.4.2.1.1 Class ios_base::failure
253 */
254#if _GLIBCXX_USE_CXX11_ABI
255 class _GLIBCXX_ABI_TAG_CXX11 failure : public system_error
256 {
257 public:
258 explicit
259 failure(const string& __str);
260
261#if __cplusplus >= 201103L
262 explicit
263 failure(const string&, const error_code&);
264
265 explicit
266 failure(const char*, const error_code& = io_errc::stream);
267#endif
268
269 virtual
270 ~failure() throw();
271
272 virtual const char*
273 what() const throw();
274 };
275#else
276 class failure : public exception
277 {
278 public:
279 // _GLIBCXX_RESOLVE_LIB_DEFECTS
280 // 48. Use of non-existent exception constructor
281 explicit
282 failure(const string& __str) throw();
283
284 // This declaration is not useless:
285 // http://gcc.gnu.org/onlinedocs/gcc-4.3.2/gcc/Vague-Linkage.html
286 virtual
287 ~failure() throw();
288
289 virtual const char*
290 what() const throw();
291
292 private:
293 string _M_msg;
294 };
295#endif
296
297 // 27.4.2.1.2 Type ios_base::fmtflags
298 /**
299 * @brief This is a bitmask type.
300 *
301 * @c @a _Ios_Fmtflags is implementation-defined, but it is valid to
302 * perform bitwise operations on these values and expect the Right
303 * Thing to happen. Defined objects of type fmtflags are:
304 * - boolalpha
305 * - dec
306 * - fixed
307 * - hex
308 * - internal
309 * - left
310 * - oct
311 * - right
312 * - scientific
313 * - showbase
314 * - showpoint
315 * - showpos
316 * - skipws
317 * - unitbuf
318 * - uppercase
319 * - adjustfield
320 * - basefield
321 * - floatfield
322 */
323 typedef _Ios_Fmtflags fmtflags;
324
325 /// Insert/extract @c bool in alphabetic rather than numeric format.
326 static const fmtflags boolalpha = _S_boolalpha;
327
328 /// Converts integer input or generates integer output in decimal base.
329 static const fmtflags dec = _S_dec;
330
331 /// Generate floating-point output in fixed-point notation.
332 static const fmtflags fixed = _S_fixed;
333
334 /// Converts integer input or generates integer output in hexadecimal base.
335 static const fmtflags hex = _S_hex;
336
337 /// Adds fill characters at a designated internal point in certain
338 /// generated output, or identical to @c right if no such point is
339 /// designated.
340 static const fmtflags internal = _S_internal;
341
342 /// Adds fill characters on the right (final positions) of certain
343 /// generated output. (I.e., the thing you print is flush left.)
344 static const fmtflags left = _S_left;
345
346 /// Converts integer input or generates integer output in octal base.
347 static const fmtflags oct = _S_oct;
348
349 /// Adds fill characters on the left (initial positions) of certain
350 /// generated output. (I.e., the thing you print is flush right.)
351 static const fmtflags right = _S_right;
352
353 /// Generates floating-point output in scientific notation.
354 static const fmtflags scientific = _S_scientific;
355
356 /// Generates a prefix indicating the numeric base of generated integer
357 /// output.
358 static const fmtflags showbase = _S_showbase;
359
360 /// Generates a decimal-point character unconditionally in generated
361 /// floating-point output.
362 static const fmtflags showpoint = _S_showpoint;
363
364 /// Generates a + sign in non-negative generated numeric output.
365 static const fmtflags showpos = _S_showpos;
366
367 /// Skips leading white space before certain input operations.
368 static const fmtflags skipws = _S_skipws;
369
370 /// Flushes output after each output operation.
371 static const fmtflags unitbuf = _S_unitbuf;
372
373 /// Replaces certain lowercase letters with their uppercase equivalents
374 /// in generated output.
375 static const fmtflags uppercase = _S_uppercase;
376
377 /// A mask of left|right|internal. Useful for the 2-arg form of @c setf.
378 static const fmtflags adjustfield = _S_adjustfield;
379
380 /// A mask of dec|oct|hex. Useful for the 2-arg form of @c setf.
381 static const fmtflags basefield = _S_basefield;
382
383 /// A mask of scientific|fixed. Useful for the 2-arg form of @c setf.
384 static const fmtflags floatfield = _S_floatfield;
385
386 // 27.4.2.1.3 Type ios_base::iostate
387 /**
388 * @brief This is a bitmask type.
389 *
390 * @c @a _Ios_Iostate is implementation-defined, but it is valid to
391 * perform bitwise operations on these values and expect the Right
392 * Thing to happen. Defined objects of type iostate are:
393 * - badbit
394 * - eofbit
395 * - failbit
396 * - goodbit
397 */
398 typedef _Ios_Iostate iostate;
399
400 /// Indicates a loss of integrity in an input or output sequence (such
401 /// as an irrecoverable read error from a file).
402 static const iostate badbit = _S_badbit;
403
404 /// Indicates that an input operation reached the end of an input sequence.
405 static const iostate eofbit = _S_eofbit;
406
407 /// Indicates that an input operation failed to read the expected
408 /// characters, or that an output operation failed to generate the
409 /// desired characters.
410 static const iostate failbit = _S_failbit;
411
412 /// Indicates all is well.
413 static const iostate goodbit = _S_goodbit;
414
415 // 27.4.2.1.4 Type ios_base::openmode
416 /**
417 * @brief This is a bitmask type.
418 *
419 * @c @a _Ios_Openmode is implementation-defined, but it is valid to
420 * perform bitwise operations on these values and expect the Right
421 * Thing to happen. Defined objects of type openmode are:
422 * - app
423 * - ate
424 * - binary
425 * - in
426 * - out
427 * - trunc
428 */
429 typedef _Ios_Openmode openmode;
430
431 /// Seek to end before each write.
432 static const openmode app = _S_app;
433
434 /// Open and seek to end immediately after opening.
435 static const openmode ate = _S_ate;
436
437 /// Perform input and output in binary mode (as opposed to text mode).
438 /// This is probably not what you think it is; see
439 /// https://gcc.gnu.org/onlinedocs/libstdc++/manual/fstreams.html#std.io.filestreams.binary
440 static const openmode binary = _S_bin;
441
442 /// Open for input. Default for @c ifstream and fstream.
443 static const openmode in = _S_in;
444
445 /// Open for output. Default for @c ofstream and fstream.
446 static const openmode out = _S_out;
447
448 /// Open for input. Default for @c ofstream.
449 static const openmode trunc = _S_trunc;
450
451 // 27.4.2.1.5 Type ios_base::seekdir
452 /**
453 * @brief This is an enumerated type.
454 *
455 * @c @a _Ios_Seekdir is implementation-defined. Defined values
456 * of type seekdir are:
457 * - beg
458 * - cur, equivalent to @c SEEK_CUR in the C standard library.
459 * - end, equivalent to @c SEEK_END in the C standard library.
460 */
461 typedef _Ios_Seekdir seekdir;
462
463 /// Request a seek relative to the beginning of the stream.
464 static const seekdir beg = _S_beg;
465
466 /// Request a seek relative to the current position within the sequence.
467 static const seekdir cur = _S_cur;
468
469 /// Request a seek relative to the current end of the sequence.
470 static const seekdir end = _S_end;
471
472 // Annex D.6
473 typedef int io_state;
474 typedef int open_mode;
475 typedef int seek_dir;
476
477 typedef std::streampos streampos;
478 typedef std::streamoff streamoff;
479
480 // Callbacks;
481 /**
482 * @brief The set of events that may be passed to an event callback.
483 *
484 * erase_event is used during ~ios() and copyfmt(). imbue_event is used
485 * during imbue(). copyfmt_event is used during copyfmt().
486 */
487 enum event
488 {
489 erase_event,
490 imbue_event,
491 copyfmt_event
492 };
493
494 /**
495 * @brief The type of an event callback function.
496 * @param __e One of the members of the event enum.
497 * @param __b Reference to the ios_base object.
498 * @param __i The integer provided when the callback was registered.
499 *
500 * Event callbacks are user defined functions that get called during
501 * several ios_base and basic_ios functions, specifically imbue(),
502 * copyfmt(), and ~ios().
503 */
504 typedef void (*event_callback) (event __e, ios_base& __b, int __i);
505
506 /**
507 * @brief Add the callback __fn with parameter __index.
508 * @param __fn The function to add.
509 * @param __index The integer to pass to the function when invoked.
510 *
511 * Registers a function as an event callback with an integer parameter to
512 * be passed to the function when invoked. Multiple copies of the
513 * function are allowed. If there are multiple callbacks, they are
514 * invoked in the order they were registered.
515 */
516 void
517 register_callback(event_callback __fn, int __index);
518
519 protected:
520 streamsize _M_precision;
521 streamsize _M_width;
522 fmtflags _M_flags;
523 iostate _M_exception;
524 iostate _M_streambuf_state;
525
526 // 27.4.2.6 Members for callbacks
527 // 27.4.2.6 ios_base callbacks
528 struct _Callback_list
529 {
530 // Data Members
531 _Callback_list* _M_next;
532 ios_base::event_callback _M_fn;
533 int _M_index;
534 _Atomic_word _M_refcount; // 0 means one reference.
535
536 _Callback_list(ios_base::event_callback __fn, int __index,
537 _Callback_list* __cb)
538 : _M_next(__cb), _M_fn(__fn), _M_index(__index), _M_refcount(0) { }
539
540 void
541 _M_add_reference() { __gnu_cxx::__atomic_add_dispatch(&_M_refcount, 1); }
542
543 // 0 => OK to delete.
544 int
545 _M_remove_reference()
546 {
547 // Be race-detector-friendly. For more info see bits/c++config.
548 _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&_M_refcount);
549 int __res = __gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1);
550 if (__res == 0)
551 {
552 _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&_M_refcount);
553 }
554 return __res;
555 }
556 };
557
558 _Callback_list* _M_callbacks;
559
560 void
561 _M_call_callbacks(event __ev) throw();
562
563 void
564 _M_dispose_callbacks(void) throw();
565
566 // 27.4.2.5 Members for iword/pword storage
567 struct _Words
568 {
569 void* _M_pword;
570 long _M_iword;
571 _Words() : _M_pword(0), _M_iword(0) { }
572 };
573
574 // Only for failed iword/pword calls.
575 _Words _M_word_zero;
576
577 // Guaranteed storage.
578 // The first 5 iword and pword slots are reserved for internal use.
579 enum { _S_local_word_size = 8 };
580 _Words _M_local_word[_S_local_word_size];
581
582 // Allocated storage.
583 int _M_word_size;
584 _Words* _M_word;
585
586 _Words&
587 _M_grow_words(int __index, bool __iword);
588
589 // Members for locale and locale caching.
590 locale _M_ios_locale;
591
592 void
593 _M_init() throw();
594
595 public:
596
597 // 27.4.2.1.6 Class ios_base::Init
598 // Used to initialize standard streams. In theory, g++ could use
599 // -finit-priority to order this stuff correctly without going
600 // through these machinations.
601 class Init
602 {
603 friend class ios_base;
604 public:
605 Init();
606 ~Init();
607
608 private:
609 static _Atomic_word _S_refcount;
610 static bool _S_synced_with_stdio;
611 };
612
613 // [27.4.2.2] fmtflags state functions
614 /**
615 * @brief Access to format flags.
616 * @return The format control flags for both input and output.
617 */
618 fmtflags
619 flags() const
620 { return _M_flags; }
621
622 /**
623 * @brief Setting new format flags all at once.
624 * @param __fmtfl The new flags to set.
625 * @return The previous format control flags.
626 *
627 * This function overwrites all the format flags with @a __fmtfl.
628 */
629 fmtflags
630 flags(fmtflags __fmtfl)
631 {
632 fmtflags __old = _M_flags;
633 _M_flags = __fmtfl;
634 return __old;
635 }
636
637 /**
638 * @brief Setting new format flags.
639 * @param __fmtfl Additional flags to set.
640 * @return The previous format control flags.
641 *
642 * This function sets additional flags in format control. Flags that
643 * were previously set remain set.
644 */
645 fmtflags
646 setf(fmtflags __fmtfl)
647 {
648 fmtflags __old = _M_flags;
649 _M_flags |= __fmtfl;
650 return __old;
651 }
652
653 /**
654 * @brief Setting new format flags.
655 * @param __fmtfl Additional flags to set.
656 * @param __mask The flags mask for @a fmtfl.
657 * @return The previous format control flags.
658 *
659 * This function clears @a mask in the format flags, then sets
660 * @a fmtfl @c & @a mask. An example mask is @c ios_base::adjustfield.
661 */
662 fmtflags
663 setf(fmtflags __fmtfl, fmtflags __mask)
664 {
665 fmtflags __old = _M_flags;
666 _M_flags &= ~__mask;
667 _M_flags |= (__fmtfl & __mask);
668 return __old;
669 }
670
671 /**
672 * @brief Clearing format flags.
673 * @param __mask The flags to unset.
674 *
675 * This function clears @a __mask in the format flags.
676 */
677 void
678 unsetf(fmtflags __mask)
679 { _M_flags &= ~__mask; }
680
681 /**
682 * @brief Flags access.
683 * @return The precision to generate on certain output operations.
684 *
685 * Be careful if you try to give a definition of @a precision here; see
686 * DR 189.
687 */
688 streamsize
689 precision() const
690 { return _M_precision; }
691
692 /**
693 * @brief Changing flags.
694 * @param __prec The new precision value.
695 * @return The previous value of precision().
696 */
697 streamsize
698 precision(streamsize __prec)
699 {
700 streamsize __old = _M_precision;
701 _M_precision = __prec;
702 return __old;
703 }
704
705 /**
706 * @brief Flags access.
707 * @return The minimum field width to generate on output operations.
708 *
709 * <em>Minimum field width</em> refers to the number of characters.
710 */
711 streamsize
712 width() const
713 { return _M_width; }
714
715 /**
716 * @brief Changing flags.
717 * @param __wide The new width value.
718 * @return The previous value of width().
719 */
720 streamsize
721 width(streamsize __wide)
722 {
723 streamsize __old = _M_width;
724 _M_width = __wide;
725 return __old;
726 }
727
728 // [27.4.2.4] ios_base static members
729 /**
730 * @brief Interaction with the standard C I/O objects.
731 * @param __sync Whether to synchronize or not.
732 * @return True if the standard streams were previously synchronized.
733 *
734 * The synchronization referred to is @e only that between the standard
735 * C facilities (e.g., stdout) and the standard C++ objects (e.g.,
736 * cout). User-declared streams are unaffected. See
737 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/fstreams.html#std.io.filestreams.binary
738 */
739 static bool
740 sync_with_stdio(bool __sync = true);
741
742 // [27.4.2.3] ios_base locale functions
743 /**
744 * @brief Setting a new locale.
745 * @param __loc The new locale.
746 * @return The previous locale.
747 *
748 * Sets the new locale for this stream, and then invokes each callback
749 * with imbue_event.
750 */
751 locale
752 imbue(const locale& __loc) throw();
753
754 /**
755 * @brief Locale access
756 * @return A copy of the current locale.
757 *
758 * If @c imbue(loc) has previously been called, then this function
759 * returns @c loc. Otherwise, it returns a copy of @c std::locale(),
760 * the global C++ locale.
761 */
762 locale
763 getloc() const
764 { return _M_ios_locale; }
765
766 /**
767 * @brief Locale access
768 * @return A reference to the current locale.
769 *
770 * Like getloc above, but returns a reference instead of
771 * generating a copy.
772 */
773 const locale&
774 _M_getloc() const
775 { return _M_ios_locale; }
776
777 // [27.4.2.5] ios_base storage functions
778 /**
779 * @brief Access to unique indices.
780 * @return An integer different from all previous calls.
781 *
782 * This function returns a unique integer every time it is called. It
783 * can be used for any purpose, but is primarily intended to be a unique
784 * index for the iword and pword functions. The expectation is that an
785 * application calls xalloc in order to obtain an index in the iword and
786 * pword arrays that can be used without fear of conflict.
787 *
788 * The implementation maintains a static variable that is incremented and
789 * returned on each invocation. xalloc is guaranteed to return an index
790 * that is safe to use in the iword and pword arrays.
791 */
792 static int
793 xalloc() throw();
794
795 /**
796 * @brief Access to integer array.
797 * @param __ix Index into the array.
798 * @return A reference to an integer associated with the index.
799 *
800 * The iword function provides access to an array of integers that can be
801 * used for any purpose. The array grows as required to hold the
802 * supplied index. All integers in the array are initialized to 0.
803 *
804 * The implementation reserves several indices. You should use xalloc to
805 * obtain an index that is safe to use. Also note that since the array
806 * can grow dynamically, it is not safe to hold onto the reference.
807 */
808 long&
809 iword(int __ix)
810 {
811 _Words& __word = (__ix < _M_word_size)
812 ? _M_word[__ix] : _M_grow_words(__ix, true);
813 return __word._M_iword;
814 }
815
816 /**
817 * @brief Access to void pointer array.
818 * @param __ix Index into the array.
819 * @return A reference to a void* associated with the index.
820 *
821 * The pword function provides access to an array of pointers that can be
822 * used for any purpose. The array grows as required to hold the
823 * supplied index. All pointers in the array are initialized to 0.
824 *
825 * The implementation reserves several indices. You should use xalloc to
826 * obtain an index that is safe to use. Also note that since the array
827 * can grow dynamically, it is not safe to hold onto the reference.
828 */
829 void*&
830 pword(int __ix)
831 {
832 _Words& __word = (__ix < _M_word_size)
833 ? _M_word[__ix] : _M_grow_words(__ix, false);
834 return __word._M_pword;
835 }
836
837 // Destructor
838 /**
839 * Invokes each callback with erase_event. Destroys local storage.
840 *
841 * Note that the ios_base object for the standard streams never gets
842 * destroyed. As a result, any callbacks registered with the standard
843 * streams will not get invoked with erase_event (unless copyfmt is
844 * used).
845 */
846 virtual ~ios_base();
847
848 protected:
849 ios_base() throw ();
850
851#if __cplusplus < 201103L
852 // _GLIBCXX_RESOLVE_LIB_DEFECTS
853 // 50. Copy constructor and assignment operator of ios_base
854 private:
855 ios_base(const ios_base&);
856
857 ios_base&
858 operator=(const ios_base&);
859#else
860 public:
861 ios_base(const ios_base&) = delete;
862
863 ios_base&
864 operator=(const ios_base&) = delete;
865
866 protected:
867 void
868 _M_move(ios_base&) noexcept;
869
870 void
871 _M_swap(ios_base& __rhs) noexcept;
872#endif
873 };
874
875 // [27.4.5.1] fmtflags manipulators
876 /// Calls base.setf(ios_base::boolalpha).
877 inline ios_base&
878 boolalpha(ios_base& __base)
879 {
880 __base.setf(ios_base::boolalpha);
881 return __base;
882 }
883
884 /// Calls base.unsetf(ios_base::boolalpha).
885 inline ios_base&
886 noboolalpha(ios_base& __base)
887 {
888 __base.unsetf(ios_base::boolalpha);
889 return __base;
890 }
891
892 /// Calls base.setf(ios_base::showbase).
893 inline ios_base&
894 showbase(ios_base& __base)
895 {
896 __base.setf(ios_base::showbase);
897 return __base;
898 }
899
900 /// Calls base.unsetf(ios_base::showbase).
901 inline ios_base&
902 noshowbase(ios_base& __base)
903 {
904 __base.unsetf(ios_base::showbase);
905 return __base;
906 }
907
908 /// Calls base.setf(ios_base::showpoint).
909 inline ios_base&
910 showpoint(ios_base& __base)
911 {
912 __base.setf(ios_base::showpoint);
913 return __base;
914 }
915
916 /// Calls base.unsetf(ios_base::showpoint).
917 inline ios_base&
918 noshowpoint(ios_base& __base)
919 {
920 __base.unsetf(ios_base::showpoint);
921 return __base;
922 }
923
924 /// Calls base.setf(ios_base::showpos).
925 inline ios_base&
926 showpos(ios_base& __base)
927 {
928 __base.setf(ios_base::showpos);
929 return __base;
930 }
931
932 /// Calls base.unsetf(ios_base::showpos).
933 inline ios_base&
934 noshowpos(ios_base& __base)
935 {
936 __base.unsetf(ios_base::showpos);
937 return __base;
938 }
939
940 /// Calls base.setf(ios_base::skipws).
941 inline ios_base&
942 skipws(ios_base& __base)
943 {
944 __base.setf(ios_base::skipws);
945 return __base;
946 }
947
948 /// Calls base.unsetf(ios_base::skipws).
949 inline ios_base&
950 noskipws(ios_base& __base)
951 {
952 __base.unsetf(ios_base::skipws);
953 return __base;
954 }
955
956 /// Calls base.setf(ios_base::uppercase).
957 inline ios_base&
958 uppercase(ios_base& __base)
959 {
960 __base.setf(ios_base::uppercase);
961 return __base;
962 }
963
964 /// Calls base.unsetf(ios_base::uppercase).
965 inline ios_base&
966 nouppercase(ios_base& __base)
967 {
968 __base.unsetf(ios_base::uppercase);
969 return __base;
970 }
971
972 /// Calls base.setf(ios_base::unitbuf).
973 inline ios_base&
974 unitbuf(ios_base& __base)
975 {
976 __base.setf(ios_base::unitbuf);
977 return __base;
978 }
979
980 /// Calls base.unsetf(ios_base::unitbuf).
981 inline ios_base&
982 nounitbuf(ios_base& __base)
983 {
984 __base.unsetf(ios_base::unitbuf);
985 return __base;
986 }
987
988 // [27.4.5.2] adjustfield manipulators
989 /// Calls base.setf(ios_base::internal, ios_base::adjustfield).
990 inline ios_base&
991 internal(ios_base& __base)
992 {
993 __base.setf(ios_base::internal, ios_base::adjustfield);
994 return __base;
995 }
996
997 /// Calls base.setf(ios_base::left, ios_base::adjustfield).
998 inline ios_base&
999 left(ios_base& __base)
1000 {
1001 __base.setf(ios_base::left, ios_base::adjustfield);
1002 return __base;
1003 }
1004
1005 /// Calls base.setf(ios_base::right, ios_base::adjustfield).
1006 inline ios_base&
1007 right(ios_base& __base)
1008 {
1009 __base.setf(ios_base::right, ios_base::adjustfield);
1010 return __base;
1011 }
1012
1013 // [27.4.5.3] basefield manipulators
1014 /// Calls base.setf(ios_base::dec, ios_base::basefield).
1015 inline ios_base&
1016 dec(ios_base& __base)
1017 {
1018 __base.setf(ios_base::dec, ios_base::basefield);
1019 return __base;
1020 }
1021
1022 /// Calls base.setf(ios_base::hex, ios_base::basefield).
1023 inline ios_base&
1024 hex(ios_base& __base)
1025 {
1026 __base.setf(ios_base::hex, ios_base::basefield);
1027 return __base;
1028 }
1029
1030 /// Calls base.setf(ios_base::oct, ios_base::basefield).
1031 inline ios_base&
1032 oct(ios_base& __base)
1033 {
1034 __base.setf(ios_base::oct, ios_base::basefield);
1035 return __base;
1036 }
1037
1038 // [27.4.5.4] floatfield manipulators
1039 /// Calls base.setf(ios_base::fixed, ios_base::floatfield).
1040 inline ios_base&
1041 fixed(ios_base& __base)
1042 {
1043 __base.setf(ios_base::fixed, ios_base::floatfield);
1044 return __base;
1045 }
1046
1047 /// Calls base.setf(ios_base::scientific, ios_base::floatfield).
1048 inline ios_base&
1049 scientific(ios_base& __base)
1050 {
1051 __base.setf(ios_base::scientific, ios_base::floatfield);
1052 return __base;
1053 }
1054
1055#if __cplusplus >= 201103L
1056 // New C++11 floatfield manipulators
1057
1058 /// Calls
1059 /// base.setf(ios_base::fixed|ios_base::scientific, ios_base::floatfield)
1060 inline ios_base&
1061 hexfloat(ios_base& __base)
1062 {
1063 __base.setf(ios_base::fixed | ios_base::scientific, ios_base::floatfield);
1064 return __base;
1065 }
1066
1067 /// Calls @c base.unsetf(ios_base::floatfield)
1068 inline ios_base&
1069 defaultfloat(ios_base& __base)
1070 {
1071 __base.unsetf(ios_base::floatfield);
1072 return __base;
1073 }
1074#endif
1075
1076_GLIBCXX_END_NAMESPACE_VERSION
1077} // namespace
1078
1079#endif /* _IOS_BASE_H */
1080