libstdc++
istream.tcc
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1// istream classes -*- C++ -*-
2
3// Copyright (C) 1997-2022 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/istream.tcc
26 * This is an internal header file, included by other library headers.
27 * Do not attempt to use it directly. @headername{istream}
28 */
29
30//
31// ISO C++ 14882: 27.6.1 Input streams
32//
33
34#ifndef _ISTREAM_TCC
35#define _ISTREAM_TCC 1
36
37#pragma GCC system_header
38
39#include <bits/cxxabi_forced.h>
40
41namespace std _GLIBCXX_VISIBILITY(default)
42{
43_GLIBCXX_BEGIN_NAMESPACE_VERSION
44
45 template<typename _CharT, typename _Traits>
46 basic_istream<_CharT, _Traits>::sentry::
47 sentry(basic_istream<_CharT, _Traits>& __in, bool __noskip) : _M_ok(false)
48 {
49 ios_base::iostate __err = ios_base::goodbit;
50 if (__in.good())
51 {
52 __try
53 {
54 if (__in.tie())
55 __in.tie()->flush();
56 if (!__noskip && bool(__in.flags() & ios_base::skipws))
57 {
58 const __int_type __eof = traits_type::eof();
59 __streambuf_type* __sb = __in.rdbuf();
60 __int_type __c = __sb->sgetc();
61
62 const __ctype_type& __ct = __check_facet(__in._M_ctype);
63 while (!traits_type::eq_int_type(__c, __eof)
64 && __ct.is(ctype_base::space,
65 traits_type::to_char_type(__c)))
66 __c = __sb->snextc();
67
68 // _GLIBCXX_RESOLVE_LIB_DEFECTS
69 // 195. Should basic_istream::sentry's constructor ever
70 // set eofbit?
71 if (traits_type::eq_int_type(__c, __eof))
72 __err |= ios_base::eofbit;
73 }
74 }
75 __catch(__cxxabiv1::__forced_unwind&)
76 {
77 __in._M_setstate(ios_base::badbit);
78 __throw_exception_again;
79 }
80 __catch(...)
81 { __in._M_setstate(ios_base::badbit); }
82 }
83
84 if (__in.good() && __err == ios_base::goodbit)
85 _M_ok = true;
86 else
87 {
88 __err |= ios_base::failbit;
89 __in.setstate(__err);
90 }
91 }
92
93 template<typename _CharT, typename _Traits>
94 template<typename _ValueT>
95 basic_istream<_CharT, _Traits>&
96 basic_istream<_CharT, _Traits>::
97 _M_extract(_ValueT& __v)
98 {
99 sentry __cerb(*this, false);
100 if (__cerb)
101 {
102 ios_base::iostate __err = ios_base::goodbit;
103 __try
104 {
105 const __num_get_type& __ng = __check_facet(this->_M_num_get);
106 __ng.get(*this, 0, *this, __err, __v);
107 }
108 __catch(__cxxabiv1::__forced_unwind&)
109 {
110 this->_M_setstate(ios_base::badbit);
111 __throw_exception_again;
112 }
113 __catch(...)
114 { this->_M_setstate(ios_base::badbit); }
115 if (__err)
116 this->setstate(__err);
117 }
118 return *this;
119 }
120
121 template<typename _CharT, typename _Traits>
122 basic_istream<_CharT, _Traits>&
123 basic_istream<_CharT, _Traits>::
124 operator>>(short& __n)
125 {
126 // _GLIBCXX_RESOLVE_LIB_DEFECTS
127 // 118. basic_istream uses nonexistent num_get member functions.
128 sentry __cerb(*this, false);
129 if (__cerb)
130 {
131 ios_base::iostate __err = ios_base::goodbit;
132 __try
133 {
134 long __l;
135 const __num_get_type& __ng = __check_facet(this->_M_num_get);
136 __ng.get(*this, 0, *this, __err, __l);
137
138 // _GLIBCXX_RESOLVE_LIB_DEFECTS
139 // 696. istream::operator>>(int&) broken.
140 if (__l < __gnu_cxx::__numeric_traits<short>::__min)
141 {
142 __err |= ios_base::failbit;
143 __n = __gnu_cxx::__numeric_traits<short>::__min;
144 }
145 else if (__l > __gnu_cxx::__numeric_traits<short>::__max)
146 {
147 __err |= ios_base::failbit;
148 __n = __gnu_cxx::__numeric_traits<short>::__max;
149 }
150 else
151 __n = short(__l);
152 }
153 __catch(__cxxabiv1::__forced_unwind&)
154 {
155 this->_M_setstate(ios_base::badbit);
156 __throw_exception_again;
157 }
158 __catch(...)
159 { this->_M_setstate(ios_base::badbit); }
160 if (__err)
161 this->setstate(__err);
162 }
163 return *this;
164 }
165
166 template<typename _CharT, typename _Traits>
167 basic_istream<_CharT, _Traits>&
168 basic_istream<_CharT, _Traits>::
169 operator>>(int& __n)
170 {
171 // _GLIBCXX_RESOLVE_LIB_DEFECTS
172 // 118. basic_istream uses nonexistent num_get member functions.
173 sentry __cerb(*this, false);
174 if (__cerb)
175 {
176 ios_base::iostate __err = ios_base::goodbit;
177 __try
178 {
179 long __l;
180 const __num_get_type& __ng = __check_facet(this->_M_num_get);
181 __ng.get(*this, 0, *this, __err, __l);
182
183 // _GLIBCXX_RESOLVE_LIB_DEFECTS
184 // 696. istream::operator>>(int&) broken.
185 if (__l < __gnu_cxx::__numeric_traits<int>::__min)
186 {
187 __err |= ios_base::failbit;
188 __n = __gnu_cxx::__numeric_traits<int>::__min;
189 }
190 else if (__l > __gnu_cxx::__numeric_traits<int>::__max)
191 {
192 __err |= ios_base::failbit;
193 __n = __gnu_cxx::__numeric_traits<int>::__max;
194 }
195 else
196 __n = int(__l);
197 }
198 __catch(__cxxabiv1::__forced_unwind&)
199 {
200 this->_M_setstate(ios_base::badbit);
201 __throw_exception_again;
202 }
203 __catch(...)
204 { this->_M_setstate(ios_base::badbit); }
205 if (__err)
206 this->setstate(__err);
207 }
208 return *this;
209 }
210
211 template<typename _CharT, typename _Traits>
212 basic_istream<_CharT, _Traits>&
213 basic_istream<_CharT, _Traits>::
214 operator>>(__streambuf_type* __sbout)
215 {
216 ios_base::iostate __err = ios_base::goodbit;
217 sentry __cerb(*this, false);
218 if (__cerb && __sbout)
219 {
220 __try
221 {
222 bool __ineof;
223 if (!__copy_streambufs_eof(this->rdbuf(), __sbout, __ineof))
224 __err |= ios_base::failbit;
225 if (__ineof)
226 __err |= ios_base::eofbit;
227 }
228 __catch(__cxxabiv1::__forced_unwind&)
229 {
230 this->_M_setstate(ios_base::failbit);
231 __throw_exception_again;
232 }
233 __catch(...)
234 { this->_M_setstate(ios_base::failbit); }
235 }
236 else if (!__sbout)
237 __err |= ios_base::failbit;
238 if (__err)
239 this->setstate(__err);
240 return *this;
241 }
242
243 template<typename _CharT, typename _Traits>
244 typename basic_istream<_CharT, _Traits>::int_type
245 basic_istream<_CharT, _Traits>::
246 get(void)
247 {
248 const int_type __eof = traits_type::eof();
249 int_type __c = __eof;
250 _M_gcount = 0;
251 ios_base::iostate __err = ios_base::goodbit;
252 sentry __cerb(*this, true);
253 if (__cerb)
254 {
255 __try
256 {
257 __c = this->rdbuf()->sbumpc();
258 // 27.6.1.1 paragraph 3
259 if (!traits_type::eq_int_type(__c, __eof))
260 _M_gcount = 1;
261 else
262 __err |= ios_base::eofbit;
263 }
264 __catch(__cxxabiv1::__forced_unwind&)
265 {
266 this->_M_setstate(ios_base::badbit);
267 __throw_exception_again;
268 }
269 __catch(...)
270 { this->_M_setstate(ios_base::badbit); }
271 }
272 if (!_M_gcount)
273 __err |= ios_base::failbit;
274 if (__err)
275 this->setstate(__err);
276 return __c;
277 }
278
279 template<typename _CharT, typename _Traits>
280 basic_istream<_CharT, _Traits>&
281 basic_istream<_CharT, _Traits>::
282 get(char_type& __c)
283 {
284 _M_gcount = 0;
285 ios_base::iostate __err = ios_base::goodbit;
286 sentry __cerb(*this, true);
287 if (__cerb)
288 {
289 __try
290 {
291 const int_type __cb = this->rdbuf()->sbumpc();
292 // 27.6.1.1 paragraph 3
293 if (!traits_type::eq_int_type(__cb, traits_type::eof()))
294 {
295 _M_gcount = 1;
296 __c = traits_type::to_char_type(__cb);
297 }
298 else
299 __err |= ios_base::eofbit;
300 }
301 __catch(__cxxabiv1::__forced_unwind&)
302 {
303 this->_M_setstate(ios_base::badbit);
304 __throw_exception_again;
305 }
306 __catch(...)
307 { this->_M_setstate(ios_base::badbit); }
308 }
309 if (!_M_gcount)
310 __err |= ios_base::failbit;
311 if (__err)
312 this->setstate(__err);
313 return *this;
314 }
315
316 template<typename _CharT, typename _Traits>
317 basic_istream<_CharT, _Traits>&
318 basic_istream<_CharT, _Traits>::
319 get(char_type* __s, streamsize __n, char_type __delim)
320 {
321 _M_gcount = 0;
322 ios_base::iostate __err = ios_base::goodbit;
323 sentry __cerb(*this, true);
324 if (__cerb)
325 {
326 __try
327 {
328 const int_type __idelim = traits_type::to_int_type(__delim);
329 const int_type __eof = traits_type::eof();
330 __streambuf_type* __sb = this->rdbuf();
331 int_type __c = __sb->sgetc();
332
333 while (_M_gcount + 1 < __n
334 && !traits_type::eq_int_type(__c, __eof)
335 && !traits_type::eq_int_type(__c, __idelim))
336 {
337 *__s++ = traits_type::to_char_type(__c);
338 ++_M_gcount;
339 __c = __sb->snextc();
340 }
341 if (traits_type::eq_int_type(__c, __eof))
342 __err |= ios_base::eofbit;
343 }
344 __catch(__cxxabiv1::__forced_unwind&)
345 {
346 this->_M_setstate(ios_base::badbit);
347 __throw_exception_again;
348 }
349 __catch(...)
350 { this->_M_setstate(ios_base::badbit); }
351 }
352 // _GLIBCXX_RESOLVE_LIB_DEFECTS
353 // 243. get and getline when sentry reports failure.
354 if (__n > 0)
355 *__s = char_type();
356 if (!_M_gcount)
357 __err |= ios_base::failbit;
358 if (__err)
359 this->setstate(__err);
360 return *this;
361 }
362
363 template<typename _CharT, typename _Traits>
364 basic_istream<_CharT, _Traits>&
365 basic_istream<_CharT, _Traits>::
366 get(__streambuf_type& __sb, char_type __delim)
367 {
368 _M_gcount = 0;
369 ios_base::iostate __err = ios_base::goodbit;
370 sentry __cerb(*this, true);
371 if (__cerb)
372 {
373 __try
374 {
375 const int_type __idelim = traits_type::to_int_type(__delim);
376 const int_type __eof = traits_type::eof();
377 __streambuf_type* __this_sb = this->rdbuf();
378 int_type __c = __this_sb->sgetc();
379 char_type __c2 = traits_type::to_char_type(__c);
380 unsigned long long __gcount = 0;
381
382 while (!traits_type::eq_int_type(__c, __eof)
383 && !traits_type::eq_int_type(__c, __idelim)
384 && !traits_type::eq_int_type(__sb.sputc(__c2), __eof))
385 {
386 ++__gcount;
387 __c = __this_sb->snextc();
388 __c2 = traits_type::to_char_type(__c);
389 }
390 if (traits_type::eq_int_type(__c, __eof))
391 __err |= ios_base::eofbit;
392 // _GLIBCXX_RESOLVE_LIB_DEFECTS
393 // 3464. istream::gcount() can overflow
394 if (__gcount <= __gnu_cxx::__numeric_traits<streamsize>::__max)
395 _M_gcount = __gcount;
396 else
397 _M_gcount = __gnu_cxx::__numeric_traits<streamsize>::__max;
398 }
399 __catch(__cxxabiv1::__forced_unwind&)
400 {
401 this->_M_setstate(ios_base::badbit);
402 __throw_exception_again;
403 }
404 __catch(...)
405 { this->_M_setstate(ios_base::badbit); }
406 }
407 if (!_M_gcount)
408 __err |= ios_base::failbit;
409 if (__err)
410 this->setstate(__err);
411 return *this;
412 }
413
414 template<typename _CharT, typename _Traits>
415 basic_istream<_CharT, _Traits>&
416 basic_istream<_CharT, _Traits>::
417 getline(char_type* __s, streamsize __n, char_type __delim)
418 {
419 _M_gcount = 0;
420 ios_base::iostate __err = ios_base::goodbit;
421 sentry __cerb(*this, true);
422 if (__cerb)
423 {
424 __try
425 {
426 const int_type __idelim = traits_type::to_int_type(__delim);
427 const int_type __eof = traits_type::eof();
428 __streambuf_type* __sb = this->rdbuf();
429 int_type __c = __sb->sgetc();
430
431 while (_M_gcount + 1 < __n
432 && !traits_type::eq_int_type(__c, __eof)
433 && !traits_type::eq_int_type(__c, __idelim))
434 {
435 *__s++ = traits_type::to_char_type(__c);
436 __c = __sb->snextc();
437 ++_M_gcount;
438 }
439 if (traits_type::eq_int_type(__c, __eof))
440 __err |= ios_base::eofbit;
441 else
442 {
443 if (traits_type::eq_int_type(__c, __idelim))
444 {
445 __sb->sbumpc();
446 ++_M_gcount;
447 }
448 else
449 __err |= ios_base::failbit;
450 }
451 }
452 __catch(__cxxabiv1::__forced_unwind&)
453 {
454 this->_M_setstate(ios_base::badbit);
455 __throw_exception_again;
456 }
457 __catch(...)
458 { this->_M_setstate(ios_base::badbit); }
459 }
460 // _GLIBCXX_RESOLVE_LIB_DEFECTS
461 // 243. get and getline when sentry reports failure.
462 if (__n > 0)
463 *__s = char_type();
464 if (!_M_gcount)
465 __err |= ios_base::failbit;
466 if (__err)
467 this->setstate(__err);
468 return *this;
469 }
470
471 // We provide three overloads, since the first two are much simpler
472 // than the general case. Also, the latter two can thus adopt the
473 // same "batchy" strategy used by getline above.
474 template<typename _CharT, typename _Traits>
475 basic_istream<_CharT, _Traits>&
476 basic_istream<_CharT, _Traits>::
477 ignore(void)
478 {
479 _M_gcount = 0;
480 sentry __cerb(*this, true);
481 if (__cerb)
482 {
483 ios_base::iostate __err = ios_base::goodbit;
484 __try
485 {
486 const int_type __eof = traits_type::eof();
487 __streambuf_type* __sb = this->rdbuf();
488
489 if (traits_type::eq_int_type(__sb->sbumpc(), __eof))
490 __err |= ios_base::eofbit;
491 else
492 _M_gcount = 1;
493 }
494 __catch(__cxxabiv1::__forced_unwind&)
495 {
496 this->_M_setstate(ios_base::badbit);
497 __throw_exception_again;
498 }
499 __catch(...)
500 { this->_M_setstate(ios_base::badbit); }
501 if (__err)
502 this->setstate(__err);
503 }
504 return *this;
505 }
506
507 template<typename _CharT, typename _Traits>
508 basic_istream<_CharT, _Traits>&
509 basic_istream<_CharT, _Traits>::
510 ignore(streamsize __n)
511 {
512 _M_gcount = 0;
513 sentry __cerb(*this, true);
514 if (__cerb && __n > 0)
515 {
516 ios_base::iostate __err = ios_base::goodbit;
517 __try
518 {
519 const int_type __eof = traits_type::eof();
520 __streambuf_type* __sb = this->rdbuf();
521 int_type __c = __sb->sgetc();
522
523 // N.B. On LFS-enabled platforms streamsize is still 32 bits
524 // wide: if we want to implement the standard mandated behavior
525 // for n == max() (see 27.6.1.3/24) we are at risk of signed
526 // integer overflow: thus these contortions. Also note that,
527 // by definition, when more than 2G chars are actually ignored,
528 // _M_gcount (the return value of gcount, that is) cannot be
529 // really correct, being unavoidably too small.
530 bool __large_ignore = false;
531 while (true)
532 {
533 while (_M_gcount < __n
534 && !traits_type::eq_int_type(__c, __eof))
535 {
536 ++_M_gcount;
537 __c = __sb->snextc();
538 }
539 if (__n == __gnu_cxx::__numeric_traits<streamsize>::__max
540 && !traits_type::eq_int_type(__c, __eof))
541 {
542 _M_gcount =
543 __gnu_cxx::__numeric_traits<streamsize>::__min;
544 __large_ignore = true;
545 }
546 else
547 break;
548 }
549
550 if (__n == __gnu_cxx::__numeric_traits<streamsize>::__max)
551 {
552 if (__large_ignore)
553 _M_gcount = __gnu_cxx::__numeric_traits<streamsize>::__max;
554
555 if (traits_type::eq_int_type(__c, __eof))
556 __err |= ios_base::eofbit;
557 }
558 else if (_M_gcount < __n)
559 {
560 if (traits_type::eq_int_type(__c, __eof))
561 __err |= ios_base::eofbit;
562 }
563 }
564 __catch(__cxxabiv1::__forced_unwind&)
565 {
566 this->_M_setstate(ios_base::badbit);
567 __throw_exception_again;
568 }
569 __catch(...)
570 { this->_M_setstate(ios_base::badbit); }
571 if (__err)
572 this->setstate(__err);
573 }
574 return *this;
575 }
576
577 template<typename _CharT, typename _Traits>
578 basic_istream<_CharT, _Traits>&
579 basic_istream<_CharT, _Traits>::
580 ignore(streamsize __n, int_type __delim)
581 {
582 _M_gcount = 0;
583 sentry __cerb(*this, true);
584 if (__cerb && __n > 0)
585 {
586 ios_base::iostate __err = ios_base::goodbit;
587 __try
588 {
589 const int_type __eof = traits_type::eof();
590 __streambuf_type* __sb = this->rdbuf();
591 int_type __c = __sb->sgetc();
592
593 // See comment above.
594 bool __large_ignore = false;
595 while (true)
596 {
597 while (_M_gcount < __n
598 && !traits_type::eq_int_type(__c, __eof)
599 && !traits_type::eq_int_type(__c, __delim))
600 {
601 ++_M_gcount;
602 __c = __sb->snextc();
603 }
604 if (__n == __gnu_cxx::__numeric_traits<streamsize>::__max
605 && !traits_type::eq_int_type(__c, __eof)
606 && !traits_type::eq_int_type(__c, __delim))
607 {
608 _M_gcount =
609 __gnu_cxx::__numeric_traits<streamsize>::__min;
610 __large_ignore = true;
611 }
612 else
613 break;
614 }
615
616 if (__n == __gnu_cxx::__numeric_traits<streamsize>::__max)
617 {
618 if (__large_ignore)
619 _M_gcount = __gnu_cxx::__numeric_traits<streamsize>::__max;
620
621 if (traits_type::eq_int_type(__c, __eof))
622 __err |= ios_base::eofbit;
623 else
624 {
625 if (_M_gcount != __n)
626 ++_M_gcount;
627 __sb->sbumpc();
628 }
629 }
630 else if (_M_gcount < __n) // implies __c == __delim or EOF
631 {
632 if (traits_type::eq_int_type(__c, __eof))
633 __err |= ios_base::eofbit;
634 else
635 {
636 ++_M_gcount;
637 __sb->sbumpc();
638 }
639 }
640 }
641 __catch(__cxxabiv1::__forced_unwind&)
642 {
643 this->_M_setstate(ios_base::badbit);
644 __throw_exception_again;
645 }
646 __catch(...)
647 { this->_M_setstate(ios_base::badbit); }
648 if (__err)
649 this->setstate(__err);
650 }
651 return *this;
652 }
653
654 template<typename _CharT, typename _Traits>
655 typename basic_istream<_CharT, _Traits>::int_type
656 basic_istream<_CharT, _Traits>::
657 peek(void)
658 {
659 int_type __c = traits_type::eof();
660 _M_gcount = 0;
661 sentry __cerb(*this, true);
662 if (__cerb)
663 {
664 ios_base::iostate __err = ios_base::goodbit;
665 __try
666 {
667 __c = this->rdbuf()->sgetc();
668 if (traits_type::eq_int_type(__c, traits_type::eof()))
669 __err |= ios_base::eofbit;
670 }
671 __catch(__cxxabiv1::__forced_unwind&)
672 {
673 this->_M_setstate(ios_base::badbit);
674 __throw_exception_again;
675 }
676 __catch(...)
677 { this->_M_setstate(ios_base::badbit); }
678 if (__err)
679 this->setstate(__err);
680 }
681 return __c;
682 }
683
684 template<typename _CharT, typename _Traits>
685 basic_istream<_CharT, _Traits>&
686 basic_istream<_CharT, _Traits>::
687 read(char_type* __s, streamsize __n)
688 {
689 _M_gcount = 0;
690 sentry __cerb(*this, true);
691 if (__cerb)
692 {
693 ios_base::iostate __err = ios_base::goodbit;
694 __try
695 {
696 _M_gcount = this->rdbuf()->sgetn(__s, __n);
697 if (_M_gcount != __n)
698 __err |= (ios_base::eofbit | ios_base::failbit);
699 }
700 __catch(__cxxabiv1::__forced_unwind&)
701 {
702 this->_M_setstate(ios_base::badbit);
703 __throw_exception_again;
704 }
705 __catch(...)
706 { this->_M_setstate(ios_base::badbit); }
707 if (__err)
708 this->setstate(__err);
709 }
710 return *this;
711 }
712
713 template<typename _CharT, typename _Traits>
714 streamsize
715 basic_istream<_CharT, _Traits>::
716 readsome(char_type* __s, streamsize __n)
717 {
718 _M_gcount = 0;
719 sentry __cerb(*this, true);
720 if (__cerb)
721 {
722 ios_base::iostate __err = ios_base::goodbit;
723 __try
724 {
725 // Cannot compare int_type with streamsize generically.
726 const streamsize __num = this->rdbuf()->in_avail();
727 if (__num > 0)
728 _M_gcount = this->rdbuf()->sgetn(__s, std::min(__num, __n));
729 else if (__num == -1)
730 __err |= ios_base::eofbit;
731 }
732 __catch(__cxxabiv1::__forced_unwind&)
733 {
734 this->_M_setstate(ios_base::badbit);
735 __throw_exception_again;
736 }
737 __catch(...)
738 { this->_M_setstate(ios_base::badbit); }
739 if (__err)
740 this->setstate(__err);
741 }
742 return _M_gcount;
743 }
744
745 template<typename _CharT, typename _Traits>
746 basic_istream<_CharT, _Traits>&
747 basic_istream<_CharT, _Traits>::
748 putback(char_type __c)
749 {
750 // _GLIBCXX_RESOLVE_LIB_DEFECTS
751 // 60. What is a formatted input function?
752 _M_gcount = 0;
753 // Clear eofbit per N3168.
754 this->clear(this->rdstate() & ~ios_base::eofbit);
755 sentry __cerb(*this, true);
756 if (__cerb)
757 {
758 ios_base::iostate __err = ios_base::goodbit;
759 __try
760 {
761 const int_type __eof = traits_type::eof();
762 __streambuf_type* __sb = this->rdbuf();
763 if (!__sb
764 || traits_type::eq_int_type(__sb->sputbackc(__c), __eof))
765 __err |= ios_base::badbit;
766 }
767 __catch(__cxxabiv1::__forced_unwind&)
768 {
769 this->_M_setstate(ios_base::badbit);
770 __throw_exception_again;
771 }
772 __catch(...)
773 { this->_M_setstate(ios_base::badbit); }
774 if (__err)
775 this->setstate(__err);
776 }
777 return *this;
778 }
779
780 template<typename _CharT, typename _Traits>
781 basic_istream<_CharT, _Traits>&
782 basic_istream<_CharT, _Traits>::
783 unget(void)
784 {
785 // _GLIBCXX_RESOLVE_LIB_DEFECTS
786 // 60. What is a formatted input function?
787 _M_gcount = 0;
788 // Clear eofbit per N3168.
789 this->clear(this->rdstate() & ~ios_base::eofbit);
790 sentry __cerb(*this, true);
791 if (__cerb)
792 {
793 ios_base::iostate __err = ios_base::goodbit;
794 __try
795 {
796 const int_type __eof = traits_type::eof();
797 __streambuf_type* __sb = this->rdbuf();
798 if (!__sb
799 || traits_type::eq_int_type(__sb->sungetc(), __eof))
800 __err |= ios_base::badbit;
801 }
802 __catch(__cxxabiv1::__forced_unwind&)
803 {
804 this->_M_setstate(ios_base::badbit);
805 __throw_exception_again;
806 }
807 __catch(...)
808 { this->_M_setstate(ios_base::badbit); }
809 if (__err)
810 this->setstate(__err);
811 }
812 return *this;
813 }
814
815 template<typename _CharT, typename _Traits>
816 int
817 basic_istream<_CharT, _Traits>::
818 sync(void)
819 {
820 // _GLIBCXX_RESOLVE_LIB_DEFECTS
821 // DR60. Do not change _M_gcount.
822 int __ret = -1;
823 sentry __cerb(*this, true);
824 if (__cerb)
825 {
826 ios_base::iostate __err = ios_base::goodbit;
827 __try
828 {
829 __streambuf_type* __sb = this->rdbuf();
830 if (__sb)
831 {
832 if (__sb->pubsync() == -1)
833 __err |= ios_base::badbit;
834 else
835 __ret = 0;
836 }
837 }
838 __catch(__cxxabiv1::__forced_unwind&)
839 {
840 this->_M_setstate(ios_base::badbit);
841 __throw_exception_again;
842 }
843 __catch(...)
844 { this->_M_setstate(ios_base::badbit); }
845 if (__err)
846 this->setstate(__err);
847 }
848 return __ret;
849 }
850
851 template<typename _CharT, typename _Traits>
852 typename basic_istream<_CharT, _Traits>::pos_type
853 basic_istream<_CharT, _Traits>::
854 tellg(void)
855 {
856 // _GLIBCXX_RESOLVE_LIB_DEFECTS
857 // DR60. Do not change _M_gcount.
858 pos_type __ret = pos_type(-1);
859 sentry __cerb(*this, true);
860 if (__cerb)
861 {
862 __try
863 {
864 if (!this->fail())
865 __ret = this->rdbuf()->pubseekoff(0, ios_base::cur,
866 ios_base::in);
867 }
868 __catch(__cxxabiv1::__forced_unwind&)
869 {
870 this->_M_setstate(ios_base::badbit);
871 __throw_exception_again;
872 }
873 __catch(...)
874 { this->_M_setstate(ios_base::badbit); }
875 }
876 return __ret;
877 }
878
879 template<typename _CharT, typename _Traits>
880 basic_istream<_CharT, _Traits>&
881 basic_istream<_CharT, _Traits>::
882 seekg(pos_type __pos)
883 {
884 // _GLIBCXX_RESOLVE_LIB_DEFECTS
885 // DR60. Do not change _M_gcount.
886 // Clear eofbit per N3168.
887 this->clear(this->rdstate() & ~ios_base::eofbit);
888 sentry __cerb(*this, true);
889 if (__cerb)
890 {
891 ios_base::iostate __err = ios_base::goodbit;
892 __try
893 {
894 if (!this->fail())
895 {
896 // 136. seekp, seekg setting wrong streams?
897 const pos_type __p = this->rdbuf()->pubseekpos(__pos,
898 ios_base::in);
899
900 // 129. Need error indication from seekp() and seekg()
901 if (__p == pos_type(off_type(-1)))
902 __err |= ios_base::failbit;
903 }
904 }
905 __catch(__cxxabiv1::__forced_unwind&)
906 {
907 this->_M_setstate(ios_base::badbit);
908 __throw_exception_again;
909 }
910 __catch(...)
911 { this->_M_setstate(ios_base::badbit); }
912 if (__err)
913 this->setstate(__err);
914 }
915 return *this;
916 }
917
918 template<typename _CharT, typename _Traits>
919 basic_istream<_CharT, _Traits>&
920 basic_istream<_CharT, _Traits>::
921 seekg(off_type __off, ios_base::seekdir __dir)
922 {
923 // _GLIBCXX_RESOLVE_LIB_DEFECTS
924 // DR60. Do not change _M_gcount.
925 // Clear eofbit per N3168.
926 this->clear(this->rdstate() & ~ios_base::eofbit);
927 sentry __cerb(*this, true);
928 if (__cerb)
929 {
930 ios_base::iostate __err = ios_base::goodbit;
931 __try
932 {
933 if (!this->fail())
934 {
935 // 136. seekp, seekg setting wrong streams?
936 const pos_type __p = this->rdbuf()->pubseekoff(__off, __dir,
937 ios_base::in);
938
939 // 129. Need error indication from seekp() and seekg()
940 if (__p == pos_type(off_type(-1)))
941 __err |= ios_base::failbit;
942 }
943 }
944 __catch(__cxxabiv1::__forced_unwind&)
945 {
946 this->_M_setstate(ios_base::badbit);
947 __throw_exception_again;
948 }
949 __catch(...)
950 { this->_M_setstate(ios_base::badbit); }
951 if (__err)
952 this->setstate(__err);
953 }
954 return *this;
955 }
956
957 // 27.6.1.2.3 Character extraction templates
958 template<typename _CharT, typename _Traits>
959 basic_istream<_CharT, _Traits>&
960 operator>>(basic_istream<_CharT, _Traits>& __in, _CharT& __c)
961 {
962 typedef basic_istream<_CharT, _Traits> __istream_type;
963 typedef typename __istream_type::int_type __int_type;
964
965 typename __istream_type::sentry __cerb(__in, false);
966 if (__cerb)
967 {
968 ios_base::iostate __err = ios_base::goodbit;
969 __try
970 {
971 const __int_type __cb = __in.rdbuf()->sbumpc();
972 if (!_Traits::eq_int_type(__cb, _Traits::eof()))
973 __c = _Traits::to_char_type(__cb);
974 else
975 __err |= (ios_base::eofbit | ios_base::failbit);
976 }
977 __catch(__cxxabiv1::__forced_unwind&)
978 {
979 __in._M_setstate(ios_base::badbit);
980 __throw_exception_again;
981 }
982 __catch(...)
983 { __in._M_setstate(ios_base::badbit); }
984 if (__err)
985 __in.setstate(__err);
986 }
987 return __in;
988 }
989
990 template<typename _CharT, typename _Traits>
991 void
992 __istream_extract(basic_istream<_CharT, _Traits>& __in, _CharT* __s,
993 streamsize __num)
994 {
995 typedef basic_istream<_CharT, _Traits> __istream_type;
996 typedef basic_streambuf<_CharT, _Traits> __streambuf_type;
997 typedef typename _Traits::int_type int_type;
998 typedef _CharT char_type;
999 typedef ctype<_CharT> __ctype_type;
1000
1001 streamsize __extracted = 0;
1002 ios_base::iostate __err = ios_base::goodbit;
1003 typename __istream_type::sentry __cerb(__in, false);
1004 if (__cerb)
1005 {
1006 __try
1007 {
1008 // Figure out how many characters to extract.
1009 streamsize __width = __in.width();
1010 if (0 < __width && __width < __num)
1011 __num = __width;
1012
1013 const __ctype_type& __ct = use_facet<__ctype_type>(__in.getloc());
1014
1015 const int_type __eof = _Traits::eof();
1016 __streambuf_type* __sb = __in.rdbuf();
1017 int_type __c = __sb->sgetc();
1018
1019 while (__extracted < __num - 1
1020 && !_Traits::eq_int_type(__c, __eof)
1021 && !__ct.is(ctype_base::space,
1022 _Traits::to_char_type(__c)))
1023 {
1024 *__s++ = _Traits::to_char_type(__c);
1025 ++__extracted;
1026 __c = __sb->snextc();
1027 }
1028
1029 if (__extracted < __num - 1
1030 && _Traits::eq_int_type(__c, __eof))
1031 __err |= ios_base::eofbit;
1032
1033 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1034 // 68. Extractors for char* should store null at end
1035 *__s = char_type();
1036 __in.width(0);
1037 }
1038 __catch(__cxxabiv1::__forced_unwind&)
1039 {
1040 __in._M_setstate(ios_base::badbit);
1041 __throw_exception_again;
1042 }
1043 __catch(...)
1044 { __in._M_setstate(ios_base::badbit); }
1045 }
1046 if (!__extracted)
1047 __err |= ios_base::failbit;
1048 if (__err)
1049 __in.setstate(__err);
1050 }
1051
1052 // 27.6.1.4 Standard basic_istream manipulators
1053 template<typename _CharT, typename _Traits>
1054 basic_istream<_CharT, _Traits>&
1055 ws(basic_istream<_CharT, _Traits>& __in)
1056 {
1057 typedef basic_istream<_CharT, _Traits> __istream_type;
1058 typedef basic_streambuf<_CharT, _Traits> __streambuf_type;
1059 typedef typename __istream_type::int_type __int_type;
1060 typedef ctype<_CharT> __ctype_type;
1061
1062 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1063 // 451. behavior of std::ws
1064 typename __istream_type::sentry __cerb(__in, true);
1065 if (__cerb)
1066 {
1067 ios_base::iostate __err = ios_base::goodbit;
1068 __try
1069 {
1070 const __ctype_type& __ct = use_facet<__ctype_type>(__in.getloc());
1071 const __int_type __eof = _Traits::eof();
1072 __streambuf_type* __sb = __in.rdbuf();
1073 __int_type __c = __sb->sgetc();
1074
1075 while (true)
1076 {
1077 if (_Traits::eq_int_type(__c, __eof))
1078 {
1079 __err = ios_base::eofbit;
1080 break;
1081 }
1082 if (!__ct.is(ctype_base::space, _Traits::to_char_type(__c)))
1083 break;
1084 __c = __sb->snextc();
1085 }
1086 }
1087 __catch (const __cxxabiv1::__forced_unwind&)
1088 {
1089 __in._M_setstate(ios_base::badbit);
1090 __throw_exception_again;
1091 }
1092 __catch (...)
1093 {
1094 __in._M_setstate(ios_base::badbit);
1095 }
1096 if (__err)
1097 __in.setstate(__err);
1098 }
1099 return __in;
1100 }
1101
1102 // Inhibit implicit instantiations for required instantiations,
1103 // which are defined via explicit instantiations elsewhere.
1104#if _GLIBCXX_EXTERN_TEMPLATE
1105 extern template class basic_istream<char>;
1106 extern template istream& ws(istream&);
1107 extern template istream& operator>>(istream&, char&);
1108 extern template istream& operator>>(istream&, unsigned char&);
1109 extern template istream& operator>>(istream&, signed char&);
1110
1111 extern template istream& istream::_M_extract(unsigned short&);
1112 extern template istream& istream::_M_extract(unsigned int&);
1113 extern template istream& istream::_M_extract(long&);
1114 extern template istream& istream::_M_extract(unsigned long&);
1115 extern template istream& istream::_M_extract(bool&);
1116#ifdef _GLIBCXX_USE_LONG_LONG
1117 extern template istream& istream::_M_extract(long long&);
1118 extern template istream& istream::_M_extract(unsigned long long&);
1119#endif
1120 extern template istream& istream::_M_extract(float&);
1121 extern template istream& istream::_M_extract(double&);
1122 extern template istream& istream::_M_extract(long double&);
1123 extern template istream& istream::_M_extract(void*&);
1124
1125 extern template class basic_iostream<char>;
1126
1127#ifdef _GLIBCXX_USE_WCHAR_T
1128 extern template class basic_istream<wchar_t>;
1129 extern template wistream& ws(wistream&);
1130 extern template wistream& operator>>(wistream&, wchar_t&);
1131 extern template void __istream_extract(wistream&, wchar_t*, streamsize);
1132
1133 extern template wistream& wistream::_M_extract(unsigned short&);
1134 extern template wistream& wistream::_M_extract(unsigned int&);
1135 extern template wistream& wistream::_M_extract(long&);
1136 extern template wistream& wistream::_M_extract(unsigned long&);
1137 extern template wistream& wistream::_M_extract(bool&);
1138#ifdef _GLIBCXX_USE_LONG_LONG
1139 extern template wistream& wistream::_M_extract(long long&);
1140 extern template wistream& wistream::_M_extract(unsigned long long&);
1141#endif
1142 extern template wistream& wistream::_M_extract(float&);
1143 extern template wistream& wistream::_M_extract(double&);
1144 extern template wistream& wistream::_M_extract(long double&);
1145 extern template wistream& wistream::_M_extract(void*&);
1146
1147 extern template class basic_iostream<wchar_t>;
1148#endif
1149#endif
1150
1151_GLIBCXX_END_NAMESPACE_VERSION
1152} // namespace std
1153
1154#endif
std::istream
basic_istream< char > istream
Base class for char input streams.
Definition: iosfwd:140
std::wistream
basic_istream< wchar_t > wistream
Base class for wchar_t input streams.
Definition: iosfwd:180
std::min
constexpr const _Tp & min(const _Tp &, const _Tp &)
This does what you think it does.
Definition: stl_algobase.h:230
std
ISO C++ entities toplevel namespace is std.
std::streamsize
ptrdiff_t streamsize
Integral type for I/O operation counts and buffer sizes.
Definition: postypes.h:68
std::ws
basic_istream< _CharT, _Traits > & ws(basic_istream< _CharT, _Traits > &__is)
Quick and easy way to eat whitespace.
Definition: istream.tcc:1055
std::basic_ios::clear
void clear(iostate __state=goodbit)
[Re]sets the error state.
Definition: basic_ios.tcc:41
std::basic_ios::tie
basic_ostream< _CharT, _Traits > * tie() const
Fetches the current tied stream.
Definition: basic_ios.h:295
std::basic_ios::setstate
void setstate(iostate __state)
Sets additional flags in the error state.
Definition: basic_ios.h:157
std::basic_ios::rdstate
iostate rdstate() const
Returns the error state of the stream buffer.
Definition: basic_ios.h:137
std::basic_ios::good
bool good() const
Fast error checking.
Definition: basic_ios.h:180
std::basic_ios::fail
bool fail() const
Fast error checking.
Definition: basic_ios.h:201
std::basic_ios::rdbuf
basic_streambuf< _CharT, _Traits > * rdbuf() const
Accessing the underlying buffer.
Definition: basic_ios.h:321
std::basic_ios< char, _Traits >::int_type
_Traits::int_type int_type
Definition: basic_ios.h:77
std::basic_streambuf
The actual work of input and output (interface).
Definition: streambuf:125
std::basic_streambuf::snextc
int_type snextc()
Getting the next character.
Definition: streambuf:305
std::basic_streambuf::sbumpc
int_type sbumpc()
Getting the next character.
Definition: streambuf:323
std::basic_streambuf::sungetc
int_type sungetc()
Moving backwards in the input stream.
Definition: streambuf:404
std::basic_streambuf::sgetc
int_type sgetc()
Getting the next character.
Definition: streambuf:345
std::basic_streambuf::pubsync
int pubsync()
Calls virtual sync function.
Definition: streambuf:278
std::basic_streambuf::sputbackc
int_type sputbackc(char_type __c)
Pushing characters back into the input stream.
Definition: streambuf:379
std::basic_streambuf::sputc
int_type sputc(char_type __c)
Entry point for all single-character output functions.
Definition: streambuf:431
std::basic_istream
Template class basic_istream.
Definition: istream:61
std::basic_istream::seekg
__istream_type & seekg(pos_type)
Changing the current read position.
Definition: istream.tcc:882
std::basic_istream::get
int_type get()
Simple extraction.
Definition: istream.tcc:246
std::basic_istream::readsome
streamsize readsome(char_type *__s, streamsize __n)
Extraction until the buffer is exhausted, but no more.
Definition: istream.tcc:716
std::basic_istream::peek
int_type peek()
Looking ahead in the stream.
Definition: istream.tcc:657
std::basic_istream::unget
__istream_type & unget()
Unextracting the previous character.
Definition: istream.tcc:783
std::basic_istream::tellg
pos_type tellg()
Getting the current read position.
Definition: istream.tcc:854
std::basic_istream::_M_gcount
streamsize _M_gcount
Definition: istream:84
std::basic_istream::ignore
__istream_type & ignore()
Simple extraction.
Definition: istream.tcc:477
std::basic_istream::read
__istream_type & read(char_type *__s, streamsize __n)
Extraction without delimiters.
Definition: istream.tcc:687
std::basic_istream::putback
__istream_type & putback(char_type __c)
Unextracting a single character.
Definition: istream.tcc:748
std::basic_istream::getline
__istream_type & getline(char_type *__s, streamsize __n, char_type __delim)
String extraction.
Definition: istream.tcc:417
std::basic_istream::operator>>
__istream_type & operator>>(__istream_type &(*__pf)(__istream_type &))
Interface for manipulators.
Definition: istream:122
std::basic_istream::sync
int sync()
Synchronizing the stream buffer.
Definition: istream.tcc:818
std::basic_istream::sentry
Performs setup work for input streams.
Definition: istream:689
std::basic_istream::sentry::sentry
sentry(basic_istream< _CharT, _Traits > &__is, bool __noskipws=false)
The constructor performs all the work.
Definition: istream.tcc:47
__cxxabiv1::__forced_unwind
Thrown as part of forced unwinding.
Definition: cxxabi_forced.h:49
std::ios_base::skipws
static const fmtflags skipws
Skips leading white space before certain input operations.
Definition: ios_base.h:391
std::ios_base::iostate
_Ios_Iostate iostate
This is a bitmask type.
Definition: ios_base.h:421
std::ios_base::cur
static const seekdir cur
Request a seek relative to the current position within the sequence.
Definition: ios_base.h:498
std::ios_base::in
static const openmode in
Open for input. Default for ifstream and fstream.
Definition: ios_base.h:466
std::ios_base::flags
fmtflags flags() const
Access to format flags.
Definition: ios_base.h:662
std::ios_base::eofbit
static const iostate eofbit
Indicates that an input operation reached the end of an input sequence.
Definition: ios_base.h:428
std::ios_base::goodbit
static const iostate goodbit
Indicates all is well.
Definition: ios_base.h:436
std::ios_base::badbit
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:425
std::ios_base::getloc
locale getloc() const
Locale access.
Definition: ios_base.h:806
std::ios_base::failbit
static const iostate failbit
Indicates that an input operation failed to read the expected characters, or that an output operation...
Definition: ios_base.h:433
std::__ctype_abstract_base::is
bool is(mask __m, char_type __c) const
Test char_type classification.
Definition: locale_facets.h:172
std::ctype
Primary class template ctype facet.
Definition: locale_facets.h:616
std::num_get
Primary class template num_get.
Definition: locale_facets.h:1961
std::num_get::get
iter_type get(iter_type __in, iter_type __end, ios_base &__io, ios_base::iostate &__err, bool &__v) const
Numeric parsing.
Definition: locale_facets.h:2007