libstdc++
istream.tcc
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1 // istream classes -*- C++ -*-
2 
3 // Copyright (C) 1997-2017 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 
41 namespace std _GLIBCXX_VISIBILITY(default)
42 {
43 _GLIBCXX_BEGIN_NAMESPACE_VERSION
44 
45  template<typename _CharT, typename _Traits>
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  if (__in.tie())
53  __in.tie()->flush();
54  if (!__noskip && bool(__in.flags() & ios_base::skipws))
55  {
56  const __int_type __eof = traits_type::eof();
57  __streambuf_type* __sb = __in.rdbuf();
58  __int_type __c = __sb->sgetc();
59 
60  const __ctype_type& __ct = __check_facet(__in._M_ctype);
61  while (!traits_type::eq_int_type(__c, __eof)
62  && __ct.is(ctype_base::space,
63  traits_type::to_char_type(__c)))
64  __c = __sb->snextc();
65 
66  // _GLIBCXX_RESOLVE_LIB_DEFECTS
67  // 195. Should basic_istream::sentry's constructor ever
68  // set eofbit?
69  if (traits_type::eq_int_type(__c, __eof))
70  __err |= ios_base::eofbit;
71  }
72  }
73 
74  if (__in.good() && __err == ios_base::goodbit)
75  _M_ok = true;
76  else
77  {
78  __err |= ios_base::failbit;
79  __in.setstate(__err);
80  }
81  }
82 
83  template<typename _CharT, typename _Traits>
84  template<typename _ValueT>
87  _M_extract(_ValueT& __v)
88  {
89  sentry __cerb(*this, false);
90  if (__cerb)
91  {
92  ios_base::iostate __err = ios_base::goodbit;
93  __try
94  {
95  const __num_get_type& __ng = __check_facet(this->_M_num_get);
96  __ng.get(*this, 0, *this, __err, __v);
97  }
99  {
100  this->_M_setstate(ios_base::badbit);
101  __throw_exception_again;
102  }
103  __catch(...)
104  { this->_M_setstate(ios_base::badbit); }
105  if (__err)
106  this->setstate(__err);
107  }
108  return *this;
109  }
110 
111  template<typename _CharT, typename _Traits>
114  operator>>(short& __n)
115  {
116  // _GLIBCXX_RESOLVE_LIB_DEFECTS
117  // 118. basic_istream uses nonexistent num_get member functions.
118  sentry __cerb(*this, false);
119  if (__cerb)
120  {
121  ios_base::iostate __err = ios_base::goodbit;
122  __try
123  {
124  long __l;
125  const __num_get_type& __ng = __check_facet(this->_M_num_get);
126  __ng.get(*this, 0, *this, __err, __l);
127 
128  // _GLIBCXX_RESOLVE_LIB_DEFECTS
129  // 696. istream::operator>>(int&) broken.
130  if (__l < __gnu_cxx::__numeric_traits<short>::__min)
131  {
132  __err |= ios_base::failbit;
133  __n = __gnu_cxx::__numeric_traits<short>::__min;
134  }
135  else if (__l > __gnu_cxx::__numeric_traits<short>::__max)
136  {
137  __err |= ios_base::failbit;
138  __n = __gnu_cxx::__numeric_traits<short>::__max;
139  }
140  else
141  __n = short(__l);
142  }
144  {
145  this->_M_setstate(ios_base::badbit);
146  __throw_exception_again;
147  }
148  __catch(...)
149  { this->_M_setstate(ios_base::badbit); }
150  if (__err)
151  this->setstate(__err);
152  }
153  return *this;
154  }
155 
156  template<typename _CharT, typename _Traits>
159  operator>>(int& __n)
160  {
161  // _GLIBCXX_RESOLVE_LIB_DEFECTS
162  // 118. basic_istream uses nonexistent num_get member functions.
163  sentry __cerb(*this, false);
164  if (__cerb)
165  {
166  ios_base::iostate __err = ios_base::goodbit;
167  __try
168  {
169  long __l;
170  const __num_get_type& __ng = __check_facet(this->_M_num_get);
171  __ng.get(*this, 0, *this, __err, __l);
172 
173  // _GLIBCXX_RESOLVE_LIB_DEFECTS
174  // 696. istream::operator>>(int&) broken.
175  if (__l < __gnu_cxx::__numeric_traits<int>::__min)
176  {
177  __err |= ios_base::failbit;
178  __n = __gnu_cxx::__numeric_traits<int>::__min;
179  }
180  else if (__l > __gnu_cxx::__numeric_traits<int>::__max)
181  {
182  __err |= ios_base::failbit;
183  __n = __gnu_cxx::__numeric_traits<int>::__max;
184  }
185  else
186  __n = int(__l);
187  }
189  {
190  this->_M_setstate(ios_base::badbit);
191  __throw_exception_again;
192  }
193  __catch(...)
194  { this->_M_setstate(ios_base::badbit); }
195  if (__err)
196  this->setstate(__err);
197  }
198  return *this;
199  }
200 
201  template<typename _CharT, typename _Traits>
205  {
206  ios_base::iostate __err = ios_base::goodbit;
207  sentry __cerb(*this, false);
208  if (__cerb && __sbout)
209  {
210  __try
211  {
212  bool __ineof;
213  if (!__copy_streambufs_eof(this->rdbuf(), __sbout, __ineof))
214  __err |= ios_base::failbit;
215  if (__ineof)
216  __err |= ios_base::eofbit;
217  }
219  {
220  this->_M_setstate(ios_base::failbit);
221  __throw_exception_again;
222  }
223  __catch(...)
224  { this->_M_setstate(ios_base::failbit); }
225  }
226  else if (!__sbout)
227  __err |= ios_base::failbit;
228  if (__err)
229  this->setstate(__err);
230  return *this;
231  }
232 
233  template<typename _CharT, typename _Traits>
234  typename basic_istream<_CharT, _Traits>::int_type
236  get(void)
237  {
238  const int_type __eof = traits_type::eof();
239  int_type __c = __eof;
240  _M_gcount = 0;
241  ios_base::iostate __err = ios_base::goodbit;
242  sentry __cerb(*this, true);
243  if (__cerb)
244  {
245  __try
246  {
247  __c = this->rdbuf()->sbumpc();
248  // 27.6.1.1 paragraph 3
249  if (!traits_type::eq_int_type(__c, __eof))
250  _M_gcount = 1;
251  else
252  __err |= ios_base::eofbit;
253  }
255  {
256  this->_M_setstate(ios_base::badbit);
257  __throw_exception_again;
258  }
259  __catch(...)
260  { this->_M_setstate(ios_base::badbit); }
261  }
262  if (!_M_gcount)
263  __err |= ios_base::failbit;
264  if (__err)
265  this->setstate(__err);
266  return __c;
267  }
268 
269  template<typename _CharT, typename _Traits>
273  {
274  _M_gcount = 0;
275  ios_base::iostate __err = ios_base::goodbit;
276  sentry __cerb(*this, true);
277  if (__cerb)
278  {
279  __try
280  {
281  const int_type __cb = this->rdbuf()->sbumpc();
282  // 27.6.1.1 paragraph 3
283  if (!traits_type::eq_int_type(__cb, traits_type::eof()))
284  {
285  _M_gcount = 1;
286  __c = traits_type::to_char_type(__cb);
287  }
288  else
289  __err |= ios_base::eofbit;
290  }
292  {
293  this->_M_setstate(ios_base::badbit);
294  __throw_exception_again;
295  }
296  __catch(...)
297  { this->_M_setstate(ios_base::badbit); }
298  }
299  if (!_M_gcount)
300  __err |= ios_base::failbit;
301  if (__err)
302  this->setstate(__err);
303  return *this;
304  }
305 
306  template<typename _CharT, typename _Traits>
309  get(char_type* __s, streamsize __n, char_type __delim)
310  {
311  _M_gcount = 0;
312  ios_base::iostate __err = ios_base::goodbit;
313  sentry __cerb(*this, true);
314  if (__cerb)
315  {
316  __try
317  {
318  const int_type __idelim = traits_type::to_int_type(__delim);
319  const int_type __eof = traits_type::eof();
320  __streambuf_type* __sb = this->rdbuf();
321  int_type __c = __sb->sgetc();
322 
323  while (_M_gcount + 1 < __n
324  && !traits_type::eq_int_type(__c, __eof)
325  && !traits_type::eq_int_type(__c, __idelim))
326  {
327  *__s++ = traits_type::to_char_type(__c);
328  ++_M_gcount;
329  __c = __sb->snextc();
330  }
331  if (traits_type::eq_int_type(__c, __eof))
332  __err |= ios_base::eofbit;
333  }
335  {
336  this->_M_setstate(ios_base::badbit);
337  __throw_exception_again;
338  }
339  __catch(...)
340  { this->_M_setstate(ios_base::badbit); }
341  }
342  // _GLIBCXX_RESOLVE_LIB_DEFECTS
343  // 243. get and getline when sentry reports failure.
344  if (__n > 0)
345  *__s = char_type();
346  if (!_M_gcount)
347  __err |= ios_base::failbit;
348  if (__err)
349  this->setstate(__err);
350  return *this;
351  }
352 
353  template<typename _CharT, typename _Traits>
357  {
358  _M_gcount = 0;
359  ios_base::iostate __err = ios_base::goodbit;
360  sentry __cerb(*this, true);
361  if (__cerb)
362  {
363  __try
364  {
365  const int_type __idelim = traits_type::to_int_type(__delim);
366  const int_type __eof = traits_type::eof();
367  __streambuf_type* __this_sb = this->rdbuf();
368  int_type __c = __this_sb->sgetc();
369  char_type __c2 = traits_type::to_char_type(__c);
370 
371  while (!traits_type::eq_int_type(__c, __eof)
372  && !traits_type::eq_int_type(__c, __idelim)
373  && !traits_type::eq_int_type(__sb.sputc(__c2), __eof))
374  {
375  ++_M_gcount;
376  __c = __this_sb->snextc();
377  __c2 = traits_type::to_char_type(__c);
378  }
379  if (traits_type::eq_int_type(__c, __eof))
380  __err |= ios_base::eofbit;
381  }
383  {
384  this->_M_setstate(ios_base::badbit);
385  __throw_exception_again;
386  }
387  __catch(...)
388  { this->_M_setstate(ios_base::badbit); }
389  }
390  if (!_M_gcount)
391  __err |= ios_base::failbit;
392  if (__err)
393  this->setstate(__err);
394  return *this;
395  }
396 
397  template<typename _CharT, typename _Traits>
401  {
402  _M_gcount = 0;
403  ios_base::iostate __err = ios_base::goodbit;
404  sentry __cerb(*this, true);
405  if (__cerb)
406  {
407  __try
408  {
409  const int_type __idelim = traits_type::to_int_type(__delim);
410  const int_type __eof = traits_type::eof();
411  __streambuf_type* __sb = this->rdbuf();
412  int_type __c = __sb->sgetc();
413 
414  while (_M_gcount + 1 < __n
415  && !traits_type::eq_int_type(__c, __eof)
416  && !traits_type::eq_int_type(__c, __idelim))
417  {
418  *__s++ = traits_type::to_char_type(__c);
419  __c = __sb->snextc();
420  ++_M_gcount;
421  }
422  if (traits_type::eq_int_type(__c, __eof))
423  __err |= ios_base::eofbit;
424  else
425  {
426  if (traits_type::eq_int_type(__c, __idelim))
427  {
428  __sb->sbumpc();
429  ++_M_gcount;
430  }
431  else
432  __err |= ios_base::failbit;
433  }
434  }
436  {
437  this->_M_setstate(ios_base::badbit);
438  __throw_exception_again;
439  }
440  __catch(...)
441  { this->_M_setstate(ios_base::badbit); }
442  }
443  // _GLIBCXX_RESOLVE_LIB_DEFECTS
444  // 243. get and getline when sentry reports failure.
445  if (__n > 0)
446  *__s = char_type();
447  if (!_M_gcount)
448  __err |= ios_base::failbit;
449  if (__err)
450  this->setstate(__err);
451  return *this;
452  }
453 
454  // We provide three overloads, since the first two are much simpler
455  // than the general case. Also, the latter two can thus adopt the
456  // same "batchy" strategy used by getline above.
457  template<typename _CharT, typename _Traits>
460  ignore(void)
461  {
462  _M_gcount = 0;
463  sentry __cerb(*this, true);
464  if (__cerb)
465  {
466  ios_base::iostate __err = ios_base::goodbit;
467  __try
468  {
469  const int_type __eof = traits_type::eof();
470  __streambuf_type* __sb = this->rdbuf();
471 
472  if (traits_type::eq_int_type(__sb->sbumpc(), __eof))
473  __err |= ios_base::eofbit;
474  else
475  _M_gcount = 1;
476  }
478  {
479  this->_M_setstate(ios_base::badbit);
480  __throw_exception_again;
481  }
482  __catch(...)
483  { this->_M_setstate(ios_base::badbit); }
484  if (__err)
485  this->setstate(__err);
486  }
487  return *this;
488  }
489 
490  template<typename _CharT, typename _Traits>
494  {
495  _M_gcount = 0;
496  sentry __cerb(*this, true);
497  if (__cerb && __n > 0)
498  {
499  ios_base::iostate __err = ios_base::goodbit;
500  __try
501  {
502  const int_type __eof = traits_type::eof();
503  __streambuf_type* __sb = this->rdbuf();
504  int_type __c = __sb->sgetc();
505 
506  // N.B. On LFS-enabled platforms streamsize is still 32 bits
507  // wide: if we want to implement the standard mandated behavior
508  // for n == max() (see 27.6.1.3/24) we are at risk of signed
509  // integer overflow: thus these contortions. Also note that,
510  // by definition, when more than 2G chars are actually ignored,
511  // _M_gcount (the return value of gcount, that is) cannot be
512  // really correct, being unavoidably too small.
513  bool __large_ignore = false;
514  while (true)
515  {
516  while (_M_gcount < __n
517  && !traits_type::eq_int_type(__c, __eof))
518  {
519  ++_M_gcount;
520  __c = __sb->snextc();
521  }
522  if (__n == __gnu_cxx::__numeric_traits<streamsize>::__max
523  && !traits_type::eq_int_type(__c, __eof))
524  {
525  _M_gcount =
526  __gnu_cxx::__numeric_traits<streamsize>::__min;
527  __large_ignore = true;
528  }
529  else
530  break;
531  }
532 
533  if (__large_ignore)
534  _M_gcount = __gnu_cxx::__numeric_traits<streamsize>::__max;
535 
536  if (traits_type::eq_int_type(__c, __eof))
537  __err |= ios_base::eofbit;
538  }
540  {
541  this->_M_setstate(ios_base::badbit);
542  __throw_exception_again;
543  }
544  __catch(...)
545  { this->_M_setstate(ios_base::badbit); }
546  if (__err)
547  this->setstate(__err);
548  }
549  return *this;
550  }
551 
552  template<typename _CharT, typename _Traits>
556  {
557  _M_gcount = 0;
558  sentry __cerb(*this, true);
559  if (__cerb && __n > 0)
560  {
561  ios_base::iostate __err = ios_base::goodbit;
562  __try
563  {
564  const int_type __eof = traits_type::eof();
565  __streambuf_type* __sb = this->rdbuf();
566  int_type __c = __sb->sgetc();
567 
568  // See comment above.
569  bool __large_ignore = false;
570  while (true)
571  {
572  while (_M_gcount < __n
573  && !traits_type::eq_int_type(__c, __eof)
574  && !traits_type::eq_int_type(__c, __delim))
575  {
576  ++_M_gcount;
577  __c = __sb->snextc();
578  }
579  if (__n == __gnu_cxx::__numeric_traits<streamsize>::__max
580  && !traits_type::eq_int_type(__c, __eof)
581  && !traits_type::eq_int_type(__c, __delim))
582  {
583  _M_gcount =
584  __gnu_cxx::__numeric_traits<streamsize>::__min;
585  __large_ignore = true;
586  }
587  else
588  break;
589  }
590 
591  if (__large_ignore)
592  _M_gcount = __gnu_cxx::__numeric_traits<streamsize>::__max;
593 
594  if (traits_type::eq_int_type(__c, __eof))
595  __err |= ios_base::eofbit;
596  else if (traits_type::eq_int_type(__c, __delim))
597  {
598  if (_M_gcount
599  < __gnu_cxx::__numeric_traits<streamsize>::__max)
600  ++_M_gcount;
601  __sb->sbumpc();
602  }
603  }
605  {
606  this->_M_setstate(ios_base::badbit);
607  __throw_exception_again;
608  }
609  __catch(...)
610  { this->_M_setstate(ios_base::badbit); }
611  if (__err)
612  this->setstate(__err);
613  }
614  return *this;
615  }
616 
617  template<typename _CharT, typename _Traits>
618  typename basic_istream<_CharT, _Traits>::int_type
620  peek(void)
621  {
622  int_type __c = traits_type::eof();
623  _M_gcount = 0;
624  sentry __cerb(*this, true);
625  if (__cerb)
626  {
627  ios_base::iostate __err = ios_base::goodbit;
628  __try
629  {
630  __c = this->rdbuf()->sgetc();
631  if (traits_type::eq_int_type(__c, traits_type::eof()))
632  __err |= ios_base::eofbit;
633  }
635  {
636  this->_M_setstate(ios_base::badbit);
637  __throw_exception_again;
638  }
639  __catch(...)
640  { this->_M_setstate(ios_base::badbit); }
641  if (__err)
642  this->setstate(__err);
643  }
644  return __c;
645  }
646 
647  template<typename _CharT, typename _Traits>
651  {
652  _M_gcount = 0;
653  sentry __cerb(*this, true);
654  if (__cerb)
655  {
656  ios_base::iostate __err = ios_base::goodbit;
657  __try
658  {
659  _M_gcount = this->rdbuf()->sgetn(__s, __n);
660  if (_M_gcount != __n)
661  __err |= (ios_base::eofbit | ios_base::failbit);
662  }
664  {
665  this->_M_setstate(ios_base::badbit);
666  __throw_exception_again;
667  }
668  __catch(...)
669  { this->_M_setstate(ios_base::badbit); }
670  if (__err)
671  this->setstate(__err);
672  }
673  return *this;
674  }
675 
676  template<typename _CharT, typename _Traits>
677  streamsize
680  {
681  _M_gcount = 0;
682  sentry __cerb(*this, true);
683  if (__cerb)
684  {
685  ios_base::iostate __err = ios_base::goodbit;
686  __try
687  {
688  // Cannot compare int_type with streamsize generically.
689  const streamsize __num = this->rdbuf()->in_avail();
690  if (__num > 0)
691  _M_gcount = this->rdbuf()->sgetn(__s, std::min(__num, __n));
692  else if (__num == -1)
693  __err |= ios_base::eofbit;
694  }
696  {
697  this->_M_setstate(ios_base::badbit);
698  __throw_exception_again;
699  }
700  __catch(...)
701  { this->_M_setstate(ios_base::badbit); }
702  if (__err)
703  this->setstate(__err);
704  }
705  return _M_gcount;
706  }
707 
708  template<typename _CharT, typename _Traits>
712  {
713  // _GLIBCXX_RESOLVE_LIB_DEFECTS
714  // 60. What is a formatted input function?
715  _M_gcount = 0;
716  // Clear eofbit per N3168.
717  this->clear(this->rdstate() & ~ios_base::eofbit);
718  sentry __cerb(*this, true);
719  if (__cerb)
720  {
721  ios_base::iostate __err = ios_base::goodbit;
722  __try
723  {
724  const int_type __eof = traits_type::eof();
725  __streambuf_type* __sb = this->rdbuf();
726  if (!__sb
727  || traits_type::eq_int_type(__sb->sputbackc(__c), __eof))
728  __err |= ios_base::badbit;
729  }
731  {
732  this->_M_setstate(ios_base::badbit);
733  __throw_exception_again;
734  }
735  __catch(...)
736  { this->_M_setstate(ios_base::badbit); }
737  if (__err)
738  this->setstate(__err);
739  }
740  return *this;
741  }
742 
743  template<typename _CharT, typename _Traits>
746  unget(void)
747  {
748  // _GLIBCXX_RESOLVE_LIB_DEFECTS
749  // 60. What is a formatted input function?
750  _M_gcount = 0;
751  // Clear eofbit per N3168.
752  this->clear(this->rdstate() & ~ios_base::eofbit);
753  sentry __cerb(*this, true);
754  if (__cerb)
755  {
756  ios_base::iostate __err = ios_base::goodbit;
757  __try
758  {
759  const int_type __eof = traits_type::eof();
760  __streambuf_type* __sb = this->rdbuf();
761  if (!__sb
762  || traits_type::eq_int_type(__sb->sungetc(), __eof))
763  __err |= ios_base::badbit;
764  }
766  {
767  this->_M_setstate(ios_base::badbit);
768  __throw_exception_again;
769  }
770  __catch(...)
771  { this->_M_setstate(ios_base::badbit); }
772  if (__err)
773  this->setstate(__err);
774  }
775  return *this;
776  }
777 
778  template<typename _CharT, typename _Traits>
779  int
781  sync(void)
782  {
783  // _GLIBCXX_RESOLVE_LIB_DEFECTS
784  // DR60. Do not change _M_gcount.
785  int __ret = -1;
786  sentry __cerb(*this, true);
787  if (__cerb)
788  {
789  ios_base::iostate __err = ios_base::goodbit;
790  __try
791  {
792  __streambuf_type* __sb = this->rdbuf();
793  if (__sb)
794  {
795  if (__sb->pubsync() == -1)
796  __err |= ios_base::badbit;
797  else
798  __ret = 0;
799  }
800  }
802  {
803  this->_M_setstate(ios_base::badbit);
804  __throw_exception_again;
805  }
806  __catch(...)
807  { this->_M_setstate(ios_base::badbit); }
808  if (__err)
809  this->setstate(__err);
810  }
811  return __ret;
812  }
813 
814  template<typename _CharT, typename _Traits>
815  typename basic_istream<_CharT, _Traits>::pos_type
817  tellg(void)
818  {
819  // _GLIBCXX_RESOLVE_LIB_DEFECTS
820  // DR60. Do not change _M_gcount.
821  pos_type __ret = pos_type(-1);
822  sentry __cerb(*this, true);
823  if (__cerb)
824  {
825  __try
826  {
827  if (!this->fail())
828  __ret = this->rdbuf()->pubseekoff(0, ios_base::cur,
829  ios_base::in);
830  }
832  {
833  this->_M_setstate(ios_base::badbit);
834  __throw_exception_again;
835  }
836  __catch(...)
837  { this->_M_setstate(ios_base::badbit); }
838  }
839  return __ret;
840  }
841 
842  template<typename _CharT, typename _Traits>
846  {
847  // _GLIBCXX_RESOLVE_LIB_DEFECTS
848  // DR60. Do not change _M_gcount.
849  // Clear eofbit per N3168.
850  this->clear(this->rdstate() & ~ios_base::eofbit);
851  sentry __cerb(*this, true);
852  if (__cerb)
853  {
854  ios_base::iostate __err = ios_base::goodbit;
855  __try
856  {
857  if (!this->fail())
858  {
859  // 136. seekp, seekg setting wrong streams?
860  const pos_type __p = this->rdbuf()->pubseekpos(__pos,
861  ios_base::in);
862 
863  // 129. Need error indication from seekp() and seekg()
864  if (__p == pos_type(off_type(-1)))
865  __err |= ios_base::failbit;
866  }
867  }
869  {
870  this->_M_setstate(ios_base::badbit);
871  __throw_exception_again;
872  }
873  __catch(...)
874  { this->_M_setstate(ios_base::badbit); }
875  if (__err)
876  this->setstate(__err);
877  }
878  return *this;
879  }
880 
881  template<typename _CharT, typename _Traits>
884  seekg(off_type __off, ios_base::seekdir __dir)
885  {
886  // _GLIBCXX_RESOLVE_LIB_DEFECTS
887  // DR60. Do not change _M_gcount.
888  // Clear eofbit per N3168.
889  this->clear(this->rdstate() & ~ios_base::eofbit);
890  sentry __cerb(*this, true);
891  if (__cerb)
892  {
893  ios_base::iostate __err = ios_base::goodbit;
894  __try
895  {
896  if (!this->fail())
897  {
898  // 136. seekp, seekg setting wrong streams?
899  const pos_type __p = this->rdbuf()->pubseekoff(__off, __dir,
900  ios_base::in);
901 
902  // 129. Need error indication from seekp() and seekg()
903  if (__p == pos_type(off_type(-1)))
904  __err |= ios_base::failbit;
905  }
906  }
908  {
909  this->_M_setstate(ios_base::badbit);
910  __throw_exception_again;
911  }
912  __catch(...)
913  { this->_M_setstate(ios_base::badbit); }
914  if (__err)
915  this->setstate(__err);
916  }
917  return *this;
918  }
919 
920  // 27.6.1.2.3 Character extraction templates
921  template<typename _CharT, typename _Traits>
924  {
925  typedef basic_istream<_CharT, _Traits> __istream_type;
926  typedef typename __istream_type::int_type __int_type;
927 
928  typename __istream_type::sentry __cerb(__in, false);
929  if (__cerb)
930  {
931  ios_base::iostate __err = ios_base::goodbit;
932  __try
933  {
934  const __int_type __cb = __in.rdbuf()->sbumpc();
935  if (!_Traits::eq_int_type(__cb, _Traits::eof()))
936  __c = _Traits::to_char_type(__cb);
937  else
938  __err |= (ios_base::eofbit | ios_base::failbit);
939  }
941  {
942  __in._M_setstate(ios_base::badbit);
943  __throw_exception_again;
944  }
945  __catch(...)
946  { __in._M_setstate(ios_base::badbit); }
947  if (__err)
948  __in.setstate(__err);
949  }
950  return __in;
951  }
952 
953  template<typename _CharT, typename _Traits>
956  {
957  typedef basic_istream<_CharT, _Traits> __istream_type;
958  typedef basic_streambuf<_CharT, _Traits> __streambuf_type;
959  typedef typename _Traits::int_type int_type;
960  typedef _CharT char_type;
961  typedef ctype<_CharT> __ctype_type;
962 
963  streamsize __extracted = 0;
964  ios_base::iostate __err = ios_base::goodbit;
965  typename __istream_type::sentry __cerb(__in, false);
966  if (__cerb)
967  {
968  __try
969  {
970  // Figure out how many characters to extract.
971  streamsize __num = __in.width();
972  if (__num <= 0)
973  __num = __gnu_cxx::__numeric_traits<streamsize>::__max;
974 
975  const __ctype_type& __ct = use_facet<__ctype_type>(__in.getloc());
976 
977  const int_type __eof = _Traits::eof();
978  __streambuf_type* __sb = __in.rdbuf();
979  int_type __c = __sb->sgetc();
980 
981  while (__extracted < __num - 1
982  && !_Traits::eq_int_type(__c, __eof)
983  && !__ct.is(ctype_base::space,
984  _Traits::to_char_type(__c)))
985  {
986  *__s++ = _Traits::to_char_type(__c);
987  ++__extracted;
988  __c = __sb->snextc();
989  }
990  if (_Traits::eq_int_type(__c, __eof))
991  __err |= ios_base::eofbit;
992 
993  // _GLIBCXX_RESOLVE_LIB_DEFECTS
994  // 68. Extractors for char* should store null at end
995  *__s = char_type();
996  __in.width(0);
997  }
999  {
1000  __in._M_setstate(ios_base::badbit);
1001  __throw_exception_again;
1002  }
1003  __catch(...)
1004  { __in._M_setstate(ios_base::badbit); }
1005  }
1006  if (!__extracted)
1007  __err |= ios_base::failbit;
1008  if (__err)
1009  __in.setstate(__err);
1010  return __in;
1011  }
1012 
1013  // 27.6.1.4 Standard basic_istream manipulators
1014  template<typename _CharT, typename _Traits>
1017  {
1018  typedef basic_istream<_CharT, _Traits> __istream_type;
1019  typedef basic_streambuf<_CharT, _Traits> __streambuf_type;
1020  typedef typename __istream_type::int_type __int_type;
1021  typedef ctype<_CharT> __ctype_type;
1022 
1023  const __ctype_type& __ct = use_facet<__ctype_type>(__in.getloc());
1024  const __int_type __eof = _Traits::eof();
1025  __streambuf_type* __sb = __in.rdbuf();
1026  __int_type __c = __sb->sgetc();
1027 
1028  while (!_Traits::eq_int_type(__c, __eof)
1029  && __ct.is(ctype_base::space, _Traits::to_char_type(__c)))
1030  __c = __sb->snextc();
1031 
1032  if (_Traits::eq_int_type(__c, __eof))
1033  __in.setstate(ios_base::eofbit);
1034  return __in;
1035  }
1036 
1037  // Inhibit implicit instantiations for required instantiations,
1038  // which are defined via explicit instantiations elsewhere.
1039 #if _GLIBCXX_EXTERN_TEMPLATE
1040  extern template class basic_istream<char>;
1041  extern template istream& ws(istream&);
1042  extern template istream& operator>>(istream&, char&);
1043  extern template istream& operator>>(istream&, char*);
1044  extern template istream& operator>>(istream&, unsigned char&);
1045  extern template istream& operator>>(istream&, signed char&);
1046  extern template istream& operator>>(istream&, unsigned char*);
1047  extern template istream& operator>>(istream&, signed char*);
1048 
1049  extern template istream& istream::_M_extract(unsigned short&);
1050  extern template istream& istream::_M_extract(unsigned int&);
1051  extern template istream& istream::_M_extract(long&);
1052  extern template istream& istream::_M_extract(unsigned long&);
1053  extern template istream& istream::_M_extract(bool&);
1054 #ifdef _GLIBCXX_USE_LONG_LONG
1055  extern template istream& istream::_M_extract(long long&);
1056  extern template istream& istream::_M_extract(unsigned long long&);
1057 #endif
1058  extern template istream& istream::_M_extract(float&);
1059  extern template istream& istream::_M_extract(double&);
1060  extern template istream& istream::_M_extract(long double&);
1061  extern template istream& istream::_M_extract(void*&);
1062 
1063  extern template class basic_iostream<char>;
1064 
1065 #ifdef _GLIBCXX_USE_WCHAR_T
1066  extern template class basic_istream<wchar_t>;
1067  extern template wistream& ws(wistream&);
1068  extern template wistream& operator>>(wistream&, wchar_t&);
1069  extern template wistream& operator>>(wistream&, wchar_t*);
1070 
1071  extern template wistream& wistream::_M_extract(unsigned short&);
1072  extern template wistream& wistream::_M_extract(unsigned int&);
1073  extern template wistream& wistream::_M_extract(long&);
1074  extern template wistream& wistream::_M_extract(unsigned long&);
1075  extern template wistream& wistream::_M_extract(bool&);
1076 #ifdef _GLIBCXX_USE_LONG_LONG
1077  extern template wistream& wistream::_M_extract(long long&);
1078  extern template wistream& wistream::_M_extract(unsigned long long&);
1079 #endif
1080  extern template wistream& wistream::_M_extract(float&);
1081  extern template wistream& wistream::_M_extract(double&);
1082  extern template wistream& wistream::_M_extract(long double&);
1083  extern template wistream& wistream::_M_extract(void*&);
1084 
1085  extern template class basic_iostream<wchar_t>;
1086 #endif
1087 #endif
1088 
1089 _GLIBCXX_END_NAMESPACE_VERSION
1090 } // namespace std
1091 
1092 #endif
int_type sputbackc(char_type __c)
Pushing characters back into the input stream.
Definition: streambuf:372
streamsize _M_gcount
Definition: istream:82
static const seekdir cur
Request a seek relative to the current position within the sequence.
Definition: ios_base.h:467
bool fail() const
Fast error checking.
Definition: basic_ios.h:201
int_type sungetc()
Moving backwards in the input stream.
Definition: streambuf:397
static const iostate failbit
Indicates that an input operation failed to read the expected characters, or that an output operation...
Definition: ios_base.h:410
static const iostate eofbit
Indicates that an input operation reached the end of an input sequence.
Definition: ios_base.h:405
void setstate(iostate __state)
Sets additional flags in the error state.
Definition: basic_ios.h:157
streamsize width() const
Flags access.
Definition: ios_base.h:712
The actual work of input and output (interface).
Definition: iosfwd:80
ISO C++ entities toplevel namespace is std.
locale getloc() const
Locale access.
Definition: ios_base.h:763
Thrown as part of forced unwinding.A magic placeholder class that can be caught by reference to recog...
Definition: cxxabi_forced.h:48
_Traits::off_type off_type
Definition: basic_ios.h:79
int_type peek()
Looking ahead in the stream.
Definition: istream.tcc:620
static const iostate goodbit
Indicates all is well.
Definition: ios_base.h:413
Primary class template num_get.This facet encapsulates the code to parse and return a number from a s...
sentry(basic_istream< _CharT, _Traits > &__is, bool __noskipws=false)
The constructor performs all the work.
Definition: istream.tcc:47
int_type sbumpc()
Getting the next character.
Definition: streambuf:316
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:402
__istream_type & operator>>(__istream_type &(*__pf)(__istream_type &))
Interface for manipulators.
Definition: istream:120
__istream_type & unget()
Unextracting the previous character.
Definition: istream.tcc:746
basic_streambuf< _CharT, _Traits > * rdbuf() const
Accessing the underlying buffer.
Definition: basic_ios.h:321
int_type get()
Simple extraction.
Definition: istream.tcc:236
static const fmtflags skipws
Skips leading white space before certain input operations.
Definition: ios_base.h:368
bool good() const
Fast error checking.
Definition: basic_ios.h:180
fmtflags flags() const
Access to format flags.
Definition: ios_base.h:619
basic_ostream< _CharT, _Traits > * tie() const
Fetches the current tied stream.
Definition: basic_ios.h:295
iter_type get(iter_type __in, iter_type __end, ios_base &__io, ios_base::iostate &__err, bool &__v) const
Numeric parsing.
__istream_type & putback(char_type __c)
Unextracting a single character.
Definition: istream.tcc:711
__istream_type & read(char_type *__s, streamsize __n)
Extraction without delimiters.
Definition: istream.tcc:650
ptrdiff_t streamsize
Integral type for I/O operation counts and buffer sizes.
Definition: postypes.h:98
bool is(mask __m, char_type __c) const
Test char_type classification.
int pubsync()
Calls virtual sync function.
Definition: streambuf:271
static const openmode in
Open for input. Default for ifstream and fstream.
Definition: ios_base.h:443
__istream_type & getline(char_type *__s, streamsize __n, char_type __delim)
String extraction.
Definition: istream.tcc:400
int_type sputc(char_type __c)
Entry point for all single-character output functions.
Definition: streambuf:424
int_type snextc()
Getting the next character.
Definition: streambuf:298
__istream_type & ignore()
Simple extraction.
Definition: istream.tcc:460
streamsize readsome(char_type *__s, streamsize __n)
Extraction until the buffer is exhausted, but no more.
Definition: istream.tcc:679
__istream_type & seekg(pos_type)
Changing the current read position.
Definition: istream.tcc:845
_Traits::pos_type pos_type
Definition: basic_ios.h:78
pos_type tellg()
Getting the current read position.
Definition: istream.tcc:817
Template class basic_istream.
Definition: iosfwd:83
_GLIBCXX14_CONSTEXPR const _Tp & min(const _Tp &, const _Tp &)
This does what you think it does.
Definition: stl_algobase.h:195
Performs setup work for input streams.
Definition: istream:686
_Traits::int_type int_type
Definition: basic_ios.h:77
int_type sgetc()
Getting the next character.
Definition: streambuf:338
void clear(iostate __state=goodbit)
[Re]sets the error state.
Definition: basic_ios.tcc:41
Primary class template ctype facet.This template class defines classification and conversion function...
iostate rdstate() const
Returns the error state of the stream buffer.
Definition: basic_ios.h:137
int sync()
Synchronizing the stream buffer.
Definition: istream.tcc:781
basic_istream< _CharT, _Traits > & ws(basic_istream< _CharT, _Traits > &__is)
Quick and easy way to eat whitespace.
Definition: istream.tcc:1016