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1 : // Iostreams base classes -*- C++ -*-
2 :
3 : // Copyright (C) 1997-2021 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 :
49 : namespace 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 in C++98
56 : // expressions involving them are not 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
83 826 : operator&(_Ios_Fmtflags __a, _Ios_Fmtflags __b)
84 826 : { return _Ios_Fmtflags(static_cast<int>(__a) & static_cast<int>(__b)); }
85 :
86 : inline _GLIBCXX_CONSTEXPR _Ios_Fmtflags
87 57 : operator|(_Ios_Fmtflags __a, _Ios_Fmtflags __b)
88 57 : { 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
95 773 : operator~(_Ios_Fmtflags __a)
96 773 : { return _Ios_Fmtflags(~static_cast<int>(__a)); }
97 :
98 : inline const _Ios_Fmtflags&
99 57 : operator|=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b)
100 57 : { return __a = __a | __b; }
101 :
102 : inline const _Ios_Fmtflags&
103 773 : operator&=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b)
104 773 : { 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 11848 : operator|(_Ios_Openmode __a, _Ios_Openmode __b)
130 11848 : { 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
169 176 : operator|(_Ios_Iostate __a, _Ios_Iostate __b)
170 176 : { 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 0 : operator|=(_Ios_Iostate& __a, _Ios_Iostate __b)
182 0 : { 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 : #if __cplusplus >= 201103L
293 : // Define the new members required by C++11,
294 : // even though the error_code cannot be stored.
295 :
296 : explicit
297 : failure(const string& __s, const error_code&) noexcept
298 : : failure(__s)
299 : { }
300 :
301 : explicit
302 : failure(const char* __s, const error_code& = error_code{})
303 : : failure(string(__s))
304 : { }
305 :
306 : // Stand-in for system_error::code() but returning by value.
307 : error_code code() const noexcept { return error_code{}; }
308 : #endif
309 :
310 : private:
311 : string _M_msg;
312 : };
313 : #endif
314 :
315 : // 27.4.2.1.2 Type ios_base::fmtflags
316 : /**
317 : * @brief This is a bitmask type.
318 : *
319 : * @c @a _Ios_Fmtflags is implementation-defined, but it is valid to
320 : * perform bitwise operations on these values and expect the Right
321 : * Thing to happen. Defined objects of type fmtflags are:
322 : * - boolalpha
323 : * - dec
324 : * - fixed
325 : * - hex
326 : * - internal
327 : * - left
328 : * - oct
329 : * - right
330 : * - scientific
331 : * - showbase
332 : * - showpoint
333 : * - showpos
334 : * - skipws
335 : * - unitbuf
336 : * - uppercase
337 : * - adjustfield
338 : * - basefield
339 : * - floatfield
340 : */
341 : typedef _Ios_Fmtflags fmtflags;
342 :
343 : /// Insert/extract @c bool in alphabetic rather than numeric format.
344 : static const fmtflags boolalpha = _S_boolalpha;
345 :
346 : /// Converts integer input or generates integer output in decimal base.
347 : static const fmtflags dec = _S_dec;
348 :
349 : /// Generate floating-point output in fixed-point notation.
350 : static const fmtflags fixed = _S_fixed;
351 :
352 : /// Converts integer input or generates integer output in hexadecimal base.
353 : static const fmtflags hex = _S_hex;
354 :
355 : /// Adds fill characters at a designated internal point in certain
356 : /// generated output, or identical to @c right if no such point is
357 : /// designated.
358 : static const fmtflags internal = _S_internal;
359 :
360 : /// Adds fill characters on the right (final positions) of certain
361 : /// generated output. (I.e., the thing you print is flush left.)
362 : static const fmtflags left = _S_left;
363 :
364 : /// Converts integer input or generates integer output in octal base.
365 : static const fmtflags oct = _S_oct;
366 :
367 : /// Adds fill characters on the left (initial positions) of certain
368 : /// generated output. (I.e., the thing you print is flush right.)
369 : static const fmtflags right = _S_right;
370 :
371 : /// Generates floating-point output in scientific notation.
372 : static const fmtflags scientific = _S_scientific;
373 :
374 : /// Generates a prefix indicating the numeric base of generated integer
375 : /// output.
376 : static const fmtflags showbase = _S_showbase;
377 :
378 : /// Generates a decimal-point character unconditionally in generated
379 : /// floating-point output.
380 : static const fmtflags showpoint = _S_showpoint;
381 :
382 : /// Generates a + sign in non-negative generated numeric output.
383 : static const fmtflags showpos = _S_showpos;
384 :
385 : /// Skips leading white space before certain input operations.
386 : static const fmtflags skipws = _S_skipws;
387 :
388 : /// Flushes output after each output operation.
389 : static const fmtflags unitbuf = _S_unitbuf;
390 :
391 : /// Replaces certain lowercase letters with their uppercase equivalents
392 : /// in generated output.
393 : static const fmtflags uppercase = _S_uppercase;
394 :
395 : /// A mask of left|right|internal. Useful for the 2-arg form of @c setf.
396 : static const fmtflags adjustfield = _S_adjustfield;
397 :
398 : /// A mask of dec|oct|hex. Useful for the 2-arg form of @c setf.
399 : static const fmtflags basefield = _S_basefield;
400 :
401 : /// A mask of scientific|fixed. Useful for the 2-arg form of @c setf.
402 : static const fmtflags floatfield = _S_floatfield;
403 :
404 : // 27.4.2.1.3 Type ios_base::iostate
405 : /**
406 : * @brief This is a bitmask type.
407 : *
408 : * @c @a _Ios_Iostate is implementation-defined, but it is valid to
409 : * perform bitwise operations on these values and expect the Right
410 : * Thing to happen. Defined objects of type iostate are:
411 : * - badbit
412 : * - eofbit
413 : * - failbit
414 : * - goodbit
415 : */
416 : typedef _Ios_Iostate iostate;
417 :
418 : /// Indicates a loss of integrity in an input or output sequence (such
419 : /// as an irrecoverable read error from a file).
420 : static const iostate badbit = _S_badbit;
421 :
422 : /// Indicates that an input operation reached the end of an input sequence.
423 : static const iostate eofbit = _S_eofbit;
424 :
425 : /// Indicates that an input operation failed to read the expected
426 : /// characters, or that an output operation failed to generate the
427 : /// desired characters.
428 : static const iostate failbit = _S_failbit;
429 :
430 : /// Indicates all is well.
431 : static const iostate goodbit = _S_goodbit;
432 :
433 : // 27.4.2.1.4 Type ios_base::openmode
434 : /**
435 : * @brief This is a bitmask type.
436 : *
437 : * @c @a _Ios_Openmode is implementation-defined, but it is valid to
438 : * perform bitwise operations on these values and expect the Right
439 : * Thing to happen. Defined objects of type openmode are:
440 : * - app
441 : * - ate
442 : * - binary
443 : * - in
444 : * - out
445 : * - trunc
446 : */
447 : typedef _Ios_Openmode openmode;
448 :
449 : /// Seek to end before each write.
450 : static const openmode app = _S_app;
451 :
452 : /// Open and seek to end immediately after opening.
453 : static const openmode ate = _S_ate;
454 :
455 : /// Perform input and output in binary mode (as opposed to text mode).
456 : /// This is probably not what you think it is; see
457 : /// https://gcc.gnu.org/onlinedocs/libstdc++/manual/fstreams.html#std.io.filestreams.binary
458 : static const openmode binary = _S_bin;
459 :
460 : /// Open for input. Default for @c ifstream and fstream.
461 : static const openmode in = _S_in;
462 :
463 : /// Open for output. Default for @c ofstream and fstream.
464 : static const openmode out = _S_out;
465 :
466 : /// Truncate an existing stream when opening. Default for @c ofstream.
467 : static const openmode trunc = _S_trunc;
468 :
469 : // 27.4.2.1.5 Type ios_base::seekdir
470 : /**
471 : * @brief This is an enumerated type.
472 : *
473 : * @c @a _Ios_Seekdir is implementation-defined. Defined values
474 : * of type seekdir are:
475 : * - beg
476 : * - cur, equivalent to @c SEEK_CUR in the C standard library.
477 : * - end, equivalent to @c SEEK_END in the C standard library.
478 : */
479 : typedef _Ios_Seekdir seekdir;
480 :
481 : /// Request a seek relative to the beginning of the stream.
482 : static const seekdir beg = _S_beg;
483 :
484 : /// Request a seek relative to the current position within the sequence.
485 : static const seekdir cur = _S_cur;
486 :
487 : /// Request a seek relative to the current end of the sequence.
488 : static const seekdir end = _S_end;
489 :
490 : #if __cplusplus <= 201402L
491 : // Annex D.6 (removed in C++17)
492 : typedef int io_state
493 : _GLIBCXX_DEPRECATED_SUGGEST("std::iostate");
494 : typedef int open_mode
495 : _GLIBCXX_DEPRECATED_SUGGEST("std::openmode");
496 : typedef int seek_dir
497 : _GLIBCXX_DEPRECATED_SUGGEST("std::seekdir");
498 :
499 : typedef std::streampos streampos
500 : _GLIBCXX_DEPRECATED_SUGGEST("std::streampos");
501 : typedef std::streamoff streamoff
502 : _GLIBCXX_DEPRECATED_SUGGEST("std::streamoff");
503 : #endif
504 :
505 : // Callbacks;
506 : /**
507 : * @brief The set of events that may be passed to an event callback.
508 : *
509 : * erase_event is used during ~ios() and copyfmt(). imbue_event is used
510 : * during imbue(). copyfmt_event is used during copyfmt().
511 : */
512 : enum event
513 : {
514 : erase_event,
515 : imbue_event,
516 : copyfmt_event
517 : };
518 :
519 : /**
520 : * @brief The type of an event callback function.
521 : * @param __e One of the members of the event enum.
522 : * @param __b Reference to the ios_base object.
523 : * @param __i The integer provided when the callback was registered.
524 : *
525 : * Event callbacks are user defined functions that get called during
526 : * several ios_base and basic_ios functions, specifically imbue(),
527 : * copyfmt(), and ~ios().
528 : */
529 : typedef void (*event_callback) (event __e, ios_base& __b, int __i);
530 :
531 : /**
532 : * @brief Add the callback __fn with parameter __index.
533 : * @param __fn The function to add.
534 : * @param __index The integer to pass to the function when invoked.
535 : *
536 : * Registers a function as an event callback with an integer parameter to
537 : * be passed to the function when invoked. Multiple copies of the
538 : * function are allowed. If there are multiple callbacks, they are
539 : * invoked in the order they were registered.
540 : */
541 : void
542 : register_callback(event_callback __fn, int __index);
543 :
544 : protected:
545 : streamsize _M_precision;
546 : streamsize _M_width;
547 : fmtflags _M_flags;
548 : iostate _M_exception;
549 : iostate _M_streambuf_state;
550 :
551 : // 27.4.2.6 Members for callbacks
552 : // 27.4.2.6 ios_base callbacks
553 : struct _Callback_list
554 : {
555 : // Data Members
556 : _Callback_list* _M_next;
557 : ios_base::event_callback _M_fn;
558 : int _M_index;
559 : _Atomic_word _M_refcount; // 0 means one reference.
560 :
561 : _Callback_list(ios_base::event_callback __fn, int __index,
562 : _Callback_list* __cb)
563 : : _M_next(__cb), _M_fn(__fn), _M_index(__index), _M_refcount(0) { }
564 :
565 : void
566 : _M_add_reference() { __gnu_cxx::__atomic_add_dispatch(&_M_refcount, 1); }
567 :
568 : // 0 => OK to delete.
569 : int
570 : _M_remove_reference()
571 : {
572 : // Be race-detector-friendly. For more info see bits/c++config.
573 : _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&_M_refcount);
574 : int __res = __gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1);
575 : if (__res == 0)
576 : {
577 : _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&_M_refcount);
578 : }
579 : return __res;
580 : }
581 : };
582 :
583 : _Callback_list* _M_callbacks;
584 :
585 : void
586 : _M_call_callbacks(event __ev) throw();
587 :
588 : void
589 : _M_dispose_callbacks(void) throw();
590 :
591 : // 27.4.2.5 Members for iword/pword storage
592 : struct _Words
593 : {
594 : void* _M_pword;
595 : long _M_iword;
596 : _Words() : _M_pword(0), _M_iword(0) { }
597 : };
598 :
599 : // Only for failed iword/pword calls.
600 : _Words _M_word_zero;
601 :
602 : // Guaranteed storage.
603 : // The first 5 iword and pword slots are reserved for internal use.
604 : enum { _S_local_word_size = 8 };
605 : _Words _M_local_word[_S_local_word_size];
606 :
607 : // Allocated storage.
608 : int _M_word_size;
609 : _Words* _M_word;
610 :
611 : _Words&
612 : _M_grow_words(int __index, bool __iword);
613 :
614 : // Members for locale and locale caching.
615 : locale _M_ios_locale;
616 :
617 : void
618 : _M_init() throw();
619 :
620 : public:
621 :
622 : // 27.4.2.1.6 Class ios_base::Init
623 : // Used to initialize standard streams. In theory, g++ could use
624 : // -finit-priority to order this stuff correctly without going
625 : // through these machinations.
626 : class Init
627 : {
628 : friend class ios_base;
629 : public:
630 : Init();
631 : ~Init();
632 :
633 : #if __cplusplus >= 201103L
634 : Init(const Init&) = default;
635 : Init& operator=(const Init&) = default;
636 : #endif
637 :
638 : private:
639 : static _Atomic_word _S_refcount;
640 : static bool _S_synced_with_stdio;
641 : };
642 :
643 : // [27.4.2.2] fmtflags state functions
644 : /**
645 : * @brief Access to format flags.
646 : * @return The format control flags for both input and output.
647 : */
648 : fmtflags
649 0 : flags() const
650 0 : { return _M_flags; }
651 :
652 : /**
653 : * @brief Setting new format flags all at once.
654 : * @param __fmtfl The new flags to set.
655 : * @return The previous format control flags.
656 : *
657 : * This function overwrites all the format flags with @a __fmtfl.
658 : */
659 : fmtflags
660 : flags(fmtflags __fmtfl)
661 : {
662 : fmtflags __old = _M_flags;
663 : _M_flags = __fmtfl;
664 : return __old;
665 : }
666 :
667 : /**
668 : * @brief Setting new format flags.
669 : * @param __fmtfl Additional flags to set.
670 : * @return The previous format control flags.
671 : *
672 : * This function sets additional flags in format control. Flags that
673 : * were previously set remain set.
674 : */
675 : fmtflags
676 4 : setf(fmtflags __fmtfl)
677 : {
678 4 : fmtflags __old = _M_flags;
679 4 : _M_flags |= __fmtfl;
680 4 : return __old;
681 : }
682 :
683 : /**
684 : * @brief Setting new format flags.
685 : * @param __fmtfl Additional flags to set.
686 : * @param __mask The flags mask for @a fmtfl.
687 : * @return The previous format control flags.
688 : *
689 : * This function clears @a mask in the format flags, then sets
690 : * @a fmtfl @c & @a mask. An example mask is @c ios_base::adjustfield.
691 : */
692 : fmtflags
693 53 : setf(fmtflags __fmtfl, fmtflags __mask)
694 : {
695 53 : fmtflags __old = _M_flags;
696 53 : _M_flags &= ~__mask;
697 53 : _M_flags |= (__fmtfl & __mask);
698 53 : return __old;
699 : }
700 :
701 : /**
702 : * @brief Clearing format flags.
703 : * @param __mask The flags to unset.
704 : *
705 : * This function clears @a __mask in the format flags.
706 : */
707 : void
708 720 : unsetf(fmtflags __mask)
709 720 : { _M_flags &= ~__mask; }
710 :
711 : /**
712 : * @brief Flags access.
713 : * @return The precision to generate on certain output operations.
714 : *
715 : * Be careful if you try to give a definition of @a precision here; see
716 : * DR 189.
717 : */
718 : streamsize
719 : precision() const
720 : { return _M_precision; }
721 :
722 : /**
723 : * @brief Changing flags.
724 : * @param __prec The new precision value.
725 : * @return The previous value of precision().
726 : */
727 : streamsize
728 2884 : precision(streamsize __prec)
729 : {
730 2884 : streamsize __old = _M_precision;
731 2884 : _M_precision = __prec;
732 2884 : return __old;
733 : }
734 :
735 : /**
736 : * @brief Flags access.
737 : * @return The minimum field width to generate on output operations.
738 : *
739 : * <em>Minimum field width</em> refers to the number of characters.
740 : */
741 : streamsize
742 : width() const
743 : { return _M_width; }
744 :
745 : /**
746 : * @brief Changing flags.
747 : * @param __wide The new width value.
748 : * @return The previous value of width().
749 : */
750 : streamsize
751 : width(streamsize __wide)
752 : {
753 : streamsize __old = _M_width;
754 : _M_width = __wide;
755 : return __old;
756 : }
757 :
758 : // [27.4.2.4] ios_base static members
759 : /**
760 : * @brief Interaction with the standard C I/O objects.
761 : * @param __sync Whether to synchronize or not.
762 : * @return True if the standard streams were previously synchronized.
763 : *
764 : * The synchronization referred to is @e only that between the standard
765 : * C facilities (e.g., stdout) and the standard C++ objects (e.g.,
766 : * cout). User-declared streams are unaffected. See
767 : * https://gcc.gnu.org/onlinedocs/libstdc++/manual/fstreams.html#std.io.filestreams.binary
768 : */
769 : static bool
770 : sync_with_stdio(bool __sync = true);
771 :
772 : // [27.4.2.3] ios_base locale functions
773 : /**
774 : * @brief Setting a new locale.
775 : * @param __loc The new locale.
776 : * @return The previous locale.
777 : *
778 : * Sets the new locale for this stream, and then invokes each callback
779 : * with imbue_event.
780 : */
781 : locale
782 : imbue(const locale& __loc) throw();
783 :
784 : /**
785 : * @brief Locale access
786 : * @return A copy of the current locale.
787 : *
788 : * If @c imbue(loc) has previously been called, then this function
789 : * returns @c loc. Otherwise, it returns a copy of @c std::locale(),
790 : * the global C++ locale.
791 : */
792 : locale
793 9 : getloc() const
794 9 : { return _M_ios_locale; }
795 :
796 : /**
797 : * @brief Locale access
798 : * @return A reference to the current locale.
799 : *
800 : * Like getloc above, but returns a reference instead of
801 : * generating a copy.
802 : */
803 : const locale&
804 : _M_getloc() const
805 : { return _M_ios_locale; }
806 :
807 : // [27.4.2.5] ios_base storage functions
808 : /**
809 : * @brief Access to unique indices.
810 : * @return An integer different from all previous calls.
811 : *
812 : * This function returns a unique integer every time it is called. It
813 : * can be used for any purpose, but is primarily intended to be a unique
814 : * index for the iword and pword functions. The expectation is that an
815 : * application calls xalloc in order to obtain an index in the iword and
816 : * pword arrays that can be used without fear of conflict.
817 : *
818 : * The implementation maintains a static variable that is incremented and
819 : * returned on each invocation. xalloc is guaranteed to return an index
820 : * that is safe to use in the iword and pword arrays.
821 : */
822 : static int
823 : xalloc() throw();
824 :
825 : /**
826 : * @brief Access to integer array.
827 : * @param __ix Index into the array.
828 : * @return A reference to an integer associated with the index.
829 : *
830 : * The iword function provides access to an array of integers that can be
831 : * used for any purpose. The array grows as required to hold the
832 : * supplied index. All integers in the array are initialized to 0.
833 : *
834 : * The implementation reserves several indices. You should use xalloc to
835 : * obtain an index that is safe to use. Also note that since the array
836 : * can grow dynamically, it is not safe to hold onto the reference.
837 : */
838 : long&
839 : iword(int __ix)
840 : {
841 : _Words& __word = ((unsigned)__ix < (unsigned)_M_word_size)
842 : ? _M_word[__ix] : _M_grow_words(__ix, true);
843 : return __word._M_iword;
844 : }
845 :
846 : /**
847 : * @brief Access to void pointer array.
848 : * @param __ix Index into the array.
849 : * @return A reference to a void* associated with the index.
850 : *
851 : * The pword function provides access to an array of pointers that can be
852 : * used for any purpose. The array grows as required to hold the
853 : * supplied index. All pointers in the array are initialized to 0.
854 : *
855 : * The implementation reserves several indices. You should use xalloc to
856 : * obtain an index that is safe to use. Also note that since the array
857 : * can grow dynamically, it is not safe to hold onto the reference.
858 : */
859 : void*&
860 : pword(int __ix)
861 : {
862 : _Words& __word = ((unsigned)__ix < (unsigned)_M_word_size)
863 : ? _M_word[__ix] : _M_grow_words(__ix, false);
864 : return __word._M_pword;
865 : }
866 :
867 : // Destructor
868 : /**
869 : * Invokes each callback with erase_event. Destroys local storage.
870 : *
871 : * Note that the ios_base object for the standard streams never gets
872 : * destroyed. As a result, any callbacks registered with the standard
873 : * streams will not get invoked with erase_event (unless copyfmt is
874 : * used).
875 : */
876 : virtual ~ios_base();
877 :
878 : protected:
879 : ios_base() throw ();
880 :
881 : #if __cplusplus < 201103L
882 : // _GLIBCXX_RESOLVE_LIB_DEFECTS
883 : // 50. Copy constructor and assignment operator of ios_base
884 : private:
885 : ios_base(const ios_base&);
886 :
887 : ios_base&
888 : operator=(const ios_base&);
889 : #else
890 : public:
891 : ios_base(const ios_base&) = delete;
892 :
893 : ios_base&
894 : operator=(const ios_base&) = delete;
895 :
896 : protected:
897 : void
898 : _M_move(ios_base&) noexcept;
899 :
900 : void
901 : _M_swap(ios_base& __rhs) noexcept;
902 : #endif
903 : };
904 :
905 : // [27.4.5.1] fmtflags manipulators
906 : /// Calls base.setf(ios_base::boolalpha).
907 : inline ios_base&
908 : boolalpha(ios_base& __base)
909 : {
910 : __base.setf(ios_base::boolalpha);
911 : return __base;
912 : }
913 :
914 : /// Calls base.unsetf(ios_base::boolalpha).
915 : inline ios_base&
916 : noboolalpha(ios_base& __base)
917 : {
918 : __base.unsetf(ios_base::boolalpha);
919 : return __base;
920 : }
921 :
922 : /// Calls base.setf(ios_base::showbase).
923 : inline ios_base&
924 : showbase(ios_base& __base)
925 : {
926 : __base.setf(ios_base::showbase);
927 : return __base;
928 : }
929 :
930 : /// Calls base.unsetf(ios_base::showbase).
931 : inline ios_base&
932 : noshowbase(ios_base& __base)
933 : {
934 : __base.unsetf(ios_base::showbase);
935 : return __base;
936 : }
937 :
938 : /// Calls base.setf(ios_base::showpoint).
939 : inline ios_base&
940 : showpoint(ios_base& __base)
941 : {
942 : __base.setf(ios_base::showpoint);
943 : return __base;
944 : }
945 :
946 : /// Calls base.unsetf(ios_base::showpoint).
947 : inline ios_base&
948 : noshowpoint(ios_base& __base)
949 : {
950 : __base.unsetf(ios_base::showpoint);
951 : return __base;
952 : }
953 :
954 : /// Calls base.setf(ios_base::showpos).
955 : inline ios_base&
956 : showpos(ios_base& __base)
957 : {
958 : __base.setf(ios_base::showpos);
959 : return __base;
960 : }
961 :
962 : /// Calls base.unsetf(ios_base::showpos).
963 : inline ios_base&
964 : noshowpos(ios_base& __base)
965 : {
966 : __base.unsetf(ios_base::showpos);
967 : return __base;
968 : }
969 :
970 : /// Calls base.setf(ios_base::skipws).
971 : inline ios_base&
972 : skipws(ios_base& __base)
973 : {
974 : __base.setf(ios_base::skipws);
975 : return __base;
976 : }
977 :
978 : /// Calls base.unsetf(ios_base::skipws).
979 : inline ios_base&
980 360 : noskipws(ios_base& __base)
981 : {
982 360 : __base.unsetf(ios_base::skipws);
983 360 : return __base;
984 : }
985 :
986 : /// Calls base.setf(ios_base::uppercase).
987 : inline ios_base&
988 4 : uppercase(ios_base& __base)
989 : {
990 4 : __base.setf(ios_base::uppercase);
991 4 : return __base;
992 : }
993 :
994 : /// Calls base.unsetf(ios_base::uppercase).
995 : inline ios_base&
996 : nouppercase(ios_base& __base)
997 : {
998 : __base.unsetf(ios_base::uppercase);
999 : return __base;
1000 : }
1001 :
1002 : /// Calls base.setf(ios_base::unitbuf).
1003 : inline ios_base&
1004 : unitbuf(ios_base& __base)
1005 : {
1006 : __base.setf(ios_base::unitbuf);
1007 : return __base;
1008 : }
1009 :
1010 : /// Calls base.unsetf(ios_base::unitbuf).
1011 : inline ios_base&
1012 : nounitbuf(ios_base& __base)
1013 : {
1014 : __base.unsetf(ios_base::unitbuf);
1015 : return __base;
1016 : }
1017 :
1018 : // [27.4.5.2] adjustfield manipulators
1019 : /// Calls base.setf(ios_base::internal, ios_base::adjustfield).
1020 : inline ios_base&
1021 : internal(ios_base& __base)
1022 : {
1023 : __base.setf(ios_base::internal, ios_base::adjustfield);
1024 : return __base;
1025 : }
1026 :
1027 : /// Calls base.setf(ios_base::left, ios_base::adjustfield).
1028 : inline ios_base&
1029 : left(ios_base& __base)
1030 : {
1031 : __base.setf(ios_base::left, ios_base::adjustfield);
1032 : return __base;
1033 : }
1034 :
1035 : /// Calls base.setf(ios_base::right, ios_base::adjustfield).
1036 : inline ios_base&
1037 : right(ios_base& __base)
1038 : {
1039 : __base.setf(ios_base::right, ios_base::adjustfield);
1040 : return __base;
1041 : }
1042 :
1043 : // [27.4.5.3] basefield manipulators
1044 : /// Calls base.setf(ios_base::dec, ios_base::basefield).
1045 : inline ios_base&
1046 : dec(ios_base& __base)
1047 : {
1048 : __base.setf(ios_base::dec, ios_base::basefield);
1049 : return __base;
1050 : }
1051 :
1052 : /// Calls base.setf(ios_base::hex, ios_base::basefield).
1053 : inline ios_base&
1054 53 : hex(ios_base& __base)
1055 : {
1056 53 : __base.setf(ios_base::hex, ios_base::basefield);
1057 53 : return __base;
1058 : }
1059 :
1060 : /// Calls base.setf(ios_base::oct, ios_base::basefield).
1061 : inline ios_base&
1062 0 : oct(ios_base& __base)
1063 : {
1064 0 : __base.setf(ios_base::oct, ios_base::basefield);
1065 0 : return __base;
1066 : }
1067 :
1068 : // [27.4.5.4] floatfield manipulators
1069 : /// Calls base.setf(ios_base::fixed, ios_base::floatfield).
1070 : inline ios_base&
1071 : fixed(ios_base& __base)
1072 : {
1073 : __base.setf(ios_base::fixed, ios_base::floatfield);
1074 : return __base;
1075 : }
1076 :
1077 : /// Calls base.setf(ios_base::scientific, ios_base::floatfield).
1078 : inline ios_base&
1079 : scientific(ios_base& __base)
1080 : {
1081 : __base.setf(ios_base::scientific, ios_base::floatfield);
1082 : return __base;
1083 : }
1084 :
1085 : #if __cplusplus >= 201103L
1086 : // New C++11 floatfield manipulators
1087 :
1088 : /// Calls
1089 : /// base.setf(ios_base::fixed|ios_base::scientific, ios_base::floatfield)
1090 : inline ios_base&
1091 : hexfloat(ios_base& __base)
1092 : {
1093 : __base.setf(ios_base::fixed | ios_base::scientific, ios_base::floatfield);
1094 : return __base;
1095 : }
1096 :
1097 : /// Calls @c base.unsetf(ios_base::floatfield)
1098 : inline ios_base&
1099 : defaultfloat(ios_base& __base)
1100 : {
1101 : __base.unsetf(ios_base::floatfield);
1102 : return __base;
1103 : }
1104 : #endif
1105 :
1106 : _GLIBCXX_END_NAMESPACE_VERSION
1107 : } // namespace
1108 :
1109 : #endif /* _IOS_BASE_H */
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