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1 : : // Input streams -*- C++ -*-
2 : :
3 : : // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
4 : : // 2006, 2007, 2008
5 : : // Free Software Foundation, Inc.
6 : : //
7 : : // This file is part of the GNU ISO C++ Library. This library is free
8 : : // software; you can redistribute it and/or modify it under the
9 : : // terms of the GNU General Public License as published by the
10 : : // Free Software Foundation; either version 2, or (at your option)
11 : : // any later version.
12 : :
13 : : // This library is distributed in the hope that it will be useful,
14 : : // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 : : // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 : : // GNU General Public License for more details.
17 : :
18 : : // You should have received a copy of the GNU General Public License
19 : : // along with this library; see the file COPYING. If not, write to
20 : : // the Free Software Foundation, 51 Franklin Street, Fifth Floor,
21 : : // Boston, MA 02110-1301, USA.
22 : :
23 : : // As a special exception, you may use this file as part of a free software
24 : : // library without restriction. Specifically, if other files instantiate
25 : : // templates or use macros or inline functions from this file, or you compile
26 : : // this file and link it with other files to produce an executable, this
27 : : // file does not by itself cause the resulting executable to be covered by
28 : : // the GNU General Public License. This exception does not however
29 : : // invalidate any other reasons why the executable file might be covered by
30 : : // the GNU General Public License.
31 : :
32 : : //
33 : : // ISO C++ 14882: 27.6.1 Input streams
34 : : //
35 : :
36 : : /** @file istream
37 : : * This is a Standard C++ Library header.
38 : : */
39 : :
40 : : #ifndef _GLIBCXX_ISTREAM
41 : : #define _GLIBCXX_ISTREAM 1
42 : :
43 : : #pragma GCC system_header
44 : :
45 : : #include <ios>
46 : : #include <ostream>
47 : :
48 : : _GLIBCXX_BEGIN_NAMESPACE(std)
49 : :
50 : : // [27.6.1.1] Template class basic_istream
51 : : /**
52 : : * @brief Controlling input.
53 : : *
54 : : * This is the base class for all input streams. It provides text
55 : : * formatting of all builtin types, and communicates with any class
56 : : * derived from basic_streambuf to do the actual input.
57 : : */
58 : : template<typename _CharT, typename _Traits>
59 : : class basic_istream : virtual public basic_ios<_CharT, _Traits>
60 : : {
61 : : public:
62 : : // Types (inherited from basic_ios (27.4.4)):
63 : : typedef _CharT char_type;
64 : : typedef typename _Traits::int_type int_type;
65 : : typedef typename _Traits::pos_type pos_type;
66 : : typedef typename _Traits::off_type off_type;
67 : : typedef _Traits traits_type;
68 : :
69 : : // Non-standard Types:
70 : : typedef basic_streambuf<_CharT, _Traits> __streambuf_type;
71 : : typedef basic_ios<_CharT, _Traits> __ios_type;
72 : : typedef basic_istream<_CharT, _Traits> __istream_type;
73 : : typedef num_get<_CharT, istreambuf_iterator<_CharT, _Traits> >
74 : : __num_get_type;
75 : : typedef ctype<_CharT> __ctype_type;
76 : :
77 : : protected:
78 : : // Data Members:
79 : : /**
80 : : * The number of characters extracted in the previous unformatted
81 : : * function; see gcount().
82 : : */
83 : : streamsize _M_gcount;
84 : :
85 : : public:
86 : : // [27.6.1.1.1] constructor/destructor
87 : : /**
88 : : * @brief Base constructor.
89 : : *
90 : : * This ctor is almost never called by the user directly, rather from
91 : : * derived classes' initialization lists, which pass a pointer to
92 : : * their own stream buffer.
93 : : */
94 : : explicit
95 : : basic_istream(__streambuf_type* __sb)
96 : : : _M_gcount(streamsize(0))
97 : : { this->init(__sb); }
98 : :
99 : : /**
100 : : * @brief Base destructor.
101 : : *
102 : : * This does very little apart from providing a virtual base dtor.
103 : : */
104 : : virtual
105 : 4976 : ~basic_istream()
106 [ - + ][ - + ]: 4976 : { _M_gcount = streamsize(0); }
107 : :
108 : : // [27.6.1.1.2] prefix/suffix
109 : : class sentry;
110 : : friend class sentry;
111 : :
112 : : // [27.6.1.2] formatted input
113 : : // [27.6.1.2.3] basic_istream::operator>>
114 : : //@{
115 : : /**
116 : : * @brief Interface for manipulators.
117 : : *
118 : : * Manipulators such as @c std::ws and @c std::dec use these
119 : : * functions in constructs like "std::cin >> std::ws". For more
120 : : * information, see the iomanip header.
121 : : */
122 : : __istream_type&
123 : : operator>>(__istream_type& (*__pf)(__istream_type&))
124 : : { return __pf(*this); }
125 : :
126 : : __istream_type&
127 : : operator>>(__ios_type& (*__pf)(__ios_type&))
128 : : {
129 : : __pf(*this);
130 : : return *this;
131 : : }
132 : :
133 : : __istream_type&
134 : : operator>>(ios_base& (*__pf)(ios_base&))
135 : : {
136 : : __pf(*this);
137 : : return *this;
138 : : }
139 : : //@}
140 : :
141 : : // [27.6.1.2.2] arithmetic extractors
142 : : /**
143 : : * @name Arithmetic Extractors
144 : : *
145 : : * All the @c operator>> functions (aka <em>formatted input
146 : : * functions</em>) have some common behavior. Each starts by
147 : : * constructing a temporary object of type std::basic_istream::sentry
148 : : * with the second argument (noskipws) set to false. This has several
149 : : * effects, concluding with the setting of a status flag; see the
150 : : * sentry documentation for more.
151 : : *
152 : : * If the sentry status is good, the function tries to extract
153 : : * whatever data is appropriate for the type of the argument.
154 : : *
155 : : * If an exception is thrown during extraction, ios_base::badbit
156 : : * will be turned on in the stream's error state without causing an
157 : : * ios_base::failure to be thrown. The original exception will then
158 : : * be rethrown.
159 : : */
160 : : //@{
161 : : /**
162 : : * @brief Basic arithmetic extractors
163 : : * @param A variable of builtin type.
164 : : * @return @c *this if successful
165 : : *
166 : : * These functions use the stream's current locale (specifically, the
167 : : * @c num_get facet) to parse the input data.
168 : : */
169 : : __istream_type&
170 : : operator>>(bool& __n)
171 : : { return _M_extract(__n); }
172 : :
173 : : __istream_type&
174 : : operator>>(short& __n);
175 : :
176 : : __istream_type&
177 : : operator>>(unsigned short& __n)
178 : : { return _M_extract(__n); }
179 : :
180 : : __istream_type&
181 : : operator>>(int& __n);
182 : :
183 : : __istream_type&
184 : : operator>>(unsigned int& __n)
185 : : { return _M_extract(__n); }
186 : :
187 : : __istream_type&
188 : : operator>>(long& __n)
189 : : { return _M_extract(__n); }
190 : :
191 : : __istream_type&
192 : : operator>>(unsigned long& __n)
193 : : { return _M_extract(__n); }
194 : :
195 : : #ifdef _GLIBCXX_USE_LONG_LONG
196 : : __istream_type&
197 : : operator>>(long long& __n)
198 : : { return _M_extract(__n); }
199 : :
200 : : __istream_type&
201 : : operator>>(unsigned long long& __n)
202 : : { return _M_extract(__n); }
203 : : #endif
204 : :
205 : : __istream_type&
206 : : operator>>(float& __f)
207 : : { return _M_extract(__f); }
208 : :
209 : : __istream_type&
210 : : operator>>(double& __f)
211 : 652 : { return _M_extract(__f); }
212 : :
213 : : __istream_type&
214 : : operator>>(long double& __f)
215 : : { return _M_extract(__f); }
216 : :
217 : : __istream_type&
218 : : operator>>(void*& __p)
219 : : { return _M_extract(__p); }
220 : :
221 : : /**
222 : : * @brief Extracting into another streambuf.
223 : : * @param sb A pointer to a streambuf
224 : : *
225 : : * This function behaves like one of the basic arithmetic extractors,
226 : : * in that it also constructs a sentry object and has the same error
227 : : * handling behavior.
228 : : *
229 : : * If @a sb is NULL, the stream will set failbit in its error state.
230 : : *
231 : : * Characters are extracted from this stream and inserted into the
232 : : * @a sb streambuf until one of the following occurs:
233 : : *
234 : : * - the input stream reaches end-of-file,
235 : : * - insertion into the output buffer fails (in this case, the
236 : : * character that would have been inserted is not extracted), or
237 : : * - an exception occurs (and in this case is caught)
238 : : *
239 : : * If the function inserts no characters, failbit is set.
240 : : */
241 : : __istream_type&
242 : : operator>>(__streambuf_type* __sb);
243 : : //@}
244 : :
245 : : // [27.6.1.3] unformatted input
246 : : /**
247 : : * @brief Character counting
248 : : * @return The number of characters extracted by the previous
249 : : * unformatted input function dispatched for this stream.
250 : : */
251 : : streamsize
252 : : gcount() const
253 : 32 : { return _M_gcount; }
254 : :
255 : : /**
256 : : * @name Unformatted Input Functions
257 : : *
258 : : * All the unformatted input functions have some common behavior.
259 : : * Each starts by constructing a temporary object of type
260 : : * std::basic_istream::sentry with the second argument (noskipws)
261 : : * set to true. This has several effects, concluding with the
262 : : * setting of a status flag; see the sentry documentation for more.
263 : : *
264 : : * If the sentry status is good, the function tries to extract
265 : : * whatever data is appropriate for the type of the argument.
266 : : *
267 : : * The number of characters extracted is stored for later retrieval
268 : : * by gcount().
269 : : *
270 : : * If an exception is thrown during extraction, ios_base::badbit
271 : : * will be turned on in the stream's error state without causing an
272 : : * ios_base::failure to be thrown. The original exception will then
273 : : * be rethrown.
274 : : */
275 : : //@{
276 : : /**
277 : : * @brief Simple extraction.
278 : : * @return A character, or eof().
279 : : *
280 : : * Tries to extract a character. If none are available, sets failbit
281 : : * and returns traits::eof().
282 : : */
283 : : int_type
284 : : get();
285 : :
286 : : /**
287 : : * @brief Simple extraction.
288 : : * @param c The character in which to store data.
289 : : * @return *this
290 : : *
291 : : * Tries to extract a character and store it in @a c. If none are
292 : : * available, sets failbit and returns traits::eof().
293 : : *
294 : : * @note This function is not overloaded on signed char and
295 : : * unsigned char.
296 : : */
297 : : __istream_type&
298 : : get(char_type& __c);
299 : :
300 : : /**
301 : : * @brief Simple multiple-character extraction.
302 : : * @param s Pointer to an array.
303 : : * @param n Maximum number of characters to store in @a s.
304 : : * @param delim A "stop" character.
305 : : * @return *this
306 : : *
307 : : * Characters are extracted and stored into @a s until one of the
308 : : * following happens:
309 : : *
310 : : * - @c n-1 characters are stored
311 : : * - the input sequence reaches EOF
312 : : * - the next character equals @a delim, in which case the character
313 : : * is not extracted
314 : : *
315 : : * If no characters are stored, failbit is set in the stream's error
316 : : * state.
317 : : *
318 : : * In any case, a null character is stored into the next location in
319 : : * the array.
320 : : *
321 : : * @note This function is not overloaded on signed char and
322 : : * unsigned char.
323 : : */
324 : : __istream_type&
325 : : get(char_type* __s, streamsize __n, char_type __delim);
326 : :
327 : : /**
328 : : * @brief Simple multiple-character extraction.
329 : : * @param s Pointer to an array.
330 : : * @param n Maximum number of characters to store in @a s.
331 : : * @return *this
332 : : *
333 : : * Returns @c get(s,n,widen('\n')).
334 : : */
335 : : __istream_type&
336 : : get(char_type* __s, streamsize __n)
337 : : { return this->get(__s, __n, this->widen('\n')); }
338 : :
339 : : /**
340 : : * @brief Extraction into another streambuf.
341 : : * @param sb A streambuf in which to store data.
342 : : * @param delim A "stop" character.
343 : : * @return *this
344 : : *
345 : : * Characters are extracted and inserted into @a sb until one of the
346 : : * following happens:
347 : : *
348 : : * - the input sequence reaches EOF
349 : : * - insertion into the output buffer fails (in this case, the
350 : : * character that would have been inserted is not extracted)
351 : : * - the next character equals @a delim (in this case, the character
352 : : * is not extracted)
353 : : * - an exception occurs (and in this case is caught)
354 : : *
355 : : * If no characters are stored, failbit is set in the stream's error
356 : : * state.
357 : : */
358 : : __istream_type&
359 : : get(__streambuf_type& __sb, char_type __delim);
360 : :
361 : : /**
362 : : * @brief Extraction into another streambuf.
363 : : * @param sb A streambuf in which to store data.
364 : : * @return *this
365 : : *
366 : : * Returns @c get(sb,widen('\n')).
367 : : */
368 : : __istream_type&
369 : : get(__streambuf_type& __sb)
370 : : { return this->get(__sb, this->widen('\n')); }
371 : :
372 : : /**
373 : : * @brief String extraction.
374 : : * @param s A character array in which to store the data.
375 : : * @param n Maximum number of characters to extract.
376 : : * @param delim A "stop" character.
377 : : * @return *this
378 : : *
379 : : * Extracts and stores characters into @a s until one of the
380 : : * following happens. Note that these criteria are required to be
381 : : * tested in the order listed here, to allow an input line to exactly
382 : : * fill the @a s array without setting failbit.
383 : : *
384 : : * -# the input sequence reaches end-of-file, in which case eofbit
385 : : * is set in the stream error state
386 : : * -# the next character equals @c delim, in which case the character
387 : : * is extracted (and therefore counted in @c gcount()) but not stored
388 : : * -# @c n-1 characters are stored, in which case failbit is set
389 : : * in the stream error state
390 : : *
391 : : * If no characters are extracted, failbit is set. (An empty line of
392 : : * input should therefore not cause failbit to be set.)
393 : : *
394 : : * In any case, a null character is stored in the next location in
395 : : * the array.
396 : : */
397 : : __istream_type&
398 : : getline(char_type* __s, streamsize __n, char_type __delim);
399 : :
400 : : /**
401 : : * @brief String extraction.
402 : : * @param s A character array in which to store the data.
403 : : * @param n Maximum number of characters to extract.
404 : : * @return *this
405 : : *
406 : : * Returns @c getline(s,n,widen('\n')).
407 : : */
408 : : __istream_type&
409 : : getline(char_type* __s, streamsize __n)
410 : : { return this->getline(__s, __n, this->widen('\n')); }
411 : :
412 : : /**
413 : : * @brief Discarding characters
414 : : * @param n Number of characters to discard.
415 : : * @param delim A "stop" character.
416 : : * @return *this
417 : : *
418 : : * Extracts characters and throws them away until one of the
419 : : * following happens:
420 : : * - if @a n @c != @c std::numeric_limits<int>::max(), @a n
421 : : * characters are extracted
422 : : * - the input sequence reaches end-of-file
423 : : * - the next character equals @a delim (in this case, the character
424 : : * is extracted); note that this condition will never occur if
425 : : * @a delim equals @c traits::eof().
426 : : *
427 : : * NB: Provide three overloads, instead of the single function
428 : : * (with defaults) mandated by the Standard: this leads to a
429 : : * better performing implementation, while still conforming to
430 : : * the Standard.
431 : : */
432 : : __istream_type&
433 : : ignore();
434 : :
435 : : __istream_type&
436 : : ignore(streamsize __n);
437 : :
438 : : __istream_type&
439 : : ignore(streamsize __n, int_type __delim);
440 : :
441 : : /**
442 : : * @brief Looking ahead in the stream
443 : : * @return The next character, or eof().
444 : : *
445 : : * If, after constructing the sentry object, @c good() is false,
446 : : * returns @c traits::eof(). Otherwise reads but does not extract
447 : : * the next input character.
448 : : */
449 : : int_type
450 : : peek();
451 : :
452 : : /**
453 : : * @brief Extraction without delimiters.
454 : : * @param s A character array.
455 : : * @param n Maximum number of characters to store.
456 : : * @return *this
457 : : *
458 : : * If the stream state is @c good(), extracts characters and stores
459 : : * them into @a s until one of the following happens:
460 : : * - @a n characters are stored
461 : : * - the input sequence reaches end-of-file, in which case the error
462 : : * state is set to @c failbit|eofbit.
463 : : *
464 : : * @note This function is not overloaded on signed char and
465 : : * unsigned char.
466 : : */
467 : : __istream_type&
468 : : read(char_type* __s, streamsize __n);
469 : :
470 : : /**
471 : : * @brief Extraction until the buffer is exhausted, but no more.
472 : : * @param s A character array.
473 : : * @param n Maximum number of characters to store.
474 : : * @return The number of characters extracted.
475 : : *
476 : : * Extracts characters and stores them into @a s depending on the
477 : : * number of characters remaining in the streambuf's buffer,
478 : : * @c rdbuf()->in_avail(), called @c A here:
479 : : * - if @c A @c == @c -1, sets eofbit and extracts no characters
480 : : * - if @c A @c == @c 0, extracts no characters
481 : : * - if @c A @c > @c 0, extracts @c min(A,n)
482 : : *
483 : : * The goal is to empty the current buffer, and to not request any
484 : : * more from the external input sequence controlled by the streambuf.
485 : : */
486 : : streamsize
487 : : readsome(char_type* __s, streamsize __n);
488 : :
489 : : /**
490 : : * @brief Unextracting a single character.
491 : : * @param c The character to push back into the input stream.
492 : : * @return *this
493 : : *
494 : : * If @c rdbuf() is not null, calls @c rdbuf()->sputbackc(c).
495 : : *
496 : : * If @c rdbuf() is null or if @c sputbackc() fails, sets badbit in
497 : : * the error state.
498 : : *
499 : : * @note Since no characters are extracted, the next call to
500 : : * @c gcount() will return 0, as required by DR 60.
501 : : */
502 : : __istream_type&
503 : : putback(char_type __c);
504 : :
505 : : /**
506 : : * @brief Unextracting the previous character.
507 : : * @return *this
508 : : *
509 : : * If @c rdbuf() is not null, calls @c rdbuf()->sungetc(c).
510 : : *
511 : : * If @c rdbuf() is null or if @c sungetc() fails, sets badbit in
512 : : * the error state.
513 : : *
514 : : * @note Since no characters are extracted, the next call to
515 : : * @c gcount() will return 0, as required by DR 60.
516 : : */
517 : : __istream_type&
518 : : unget();
519 : :
520 : : /**
521 : : * @brief Synchronizing the stream buffer.
522 : : * @return 0 on success, -1 on failure
523 : : *
524 : : * If @c rdbuf() is a null pointer, returns -1.
525 : : *
526 : : * Otherwise, calls @c rdbuf()->pubsync(), and if that returns -1,
527 : : * sets badbit and returns -1.
528 : : *
529 : : * Otherwise, returns 0.
530 : : *
531 : : * @note This function does not count the number of characters
532 : : * extracted, if any, and therefore does not affect the next
533 : : * call to @c gcount().
534 : : */
535 : : int
536 : : sync();
537 : :
538 : : /**
539 : : * @brief Getting the current read position.
540 : : * @return A file position object.
541 : : *
542 : : * If @c fail() is not false, returns @c pos_type(-1) to indicate
543 : : * failure. Otherwise returns @c rdbuf()->pubseekoff(0,cur,in).
544 : : *
545 : : * @note This function does not count the number of characters
546 : : * extracted, if any, and therefore does not affect the next
547 : : * call to @c gcount().
548 : : */
549 : : pos_type
550 : : tellg();
551 : :
552 : : /**
553 : : * @brief Changing the current read position.
554 : : * @param pos A file position object.
555 : : * @return *this
556 : : *
557 : : * If @c fail() is not true, calls @c rdbuf()->pubseekpos(pos). If
558 : : * that function fails, sets failbit.
559 : : *
560 : : * @note This function does not count the number of characters
561 : : * extracted, if any, and therefore does not affect the next
562 : : * call to @c gcount().
563 : : */
564 : : __istream_type&
565 : : seekg(pos_type);
566 : :
567 : : /**
568 : : * @brief Changing the current read position.
569 : : * @param off A file offset object.
570 : : * @param dir The direction in which to seek.
571 : : * @return *this
572 : : *
573 : : * If @c fail() is not true, calls @c rdbuf()->pubseekoff(off,dir).
574 : : * If that function fails, sets failbit.
575 : : *
576 : : * @note This function does not count the number of characters
577 : : * extracted, if any, and therefore does not affect the next
578 : : * call to @c gcount().
579 : : */
580 : : __istream_type&
581 : : seekg(off_type, ios_base::seekdir);
582 : : //@}
583 : :
584 : : protected:
585 : 4952 : basic_istream()
586 : 4952 : : _M_gcount(streamsize(0))
587 : 4952 : { this->init(0); }
588 : :
589 : : template<typename _ValueT>
590 : : __istream_type&
591 : : _M_extract(_ValueT& __v);
592 : : };
593 : :
594 : : // Explicit specialization declarations, defined in src/istream.cc.
595 : : template<>
596 : : basic_istream<char>&
597 : : basic_istream<char>::
598 : : getline(char_type* __s, streamsize __n, char_type __delim);
599 : :
600 : : template<>
601 : : basic_istream<char>&
602 : : basic_istream<char>::
603 : : ignore(streamsize __n);
604 : :
605 : : template<>
606 : : basic_istream<char>&
607 : : basic_istream<char>::
608 : : ignore(streamsize __n, int_type __delim);
609 : :
610 : : #ifdef _GLIBCXX_USE_WCHAR_T
611 : : template<>
612 : : basic_istream<wchar_t>&
613 : : basic_istream<wchar_t>::
614 : : getline(char_type* __s, streamsize __n, char_type __delim);
615 : :
616 : : template<>
617 : : basic_istream<wchar_t>&
618 : : basic_istream<wchar_t>::
619 : : ignore(streamsize __n);
620 : :
621 : : template<>
622 : : basic_istream<wchar_t>&
623 : : basic_istream<wchar_t>::
624 : : ignore(streamsize __n, int_type __delim);
625 : : #endif
626 : :
627 : : /**
628 : : * @brief Performs setup work for input streams.
629 : : *
630 : : * Objects of this class are created before all of the standard
631 : : * extractors are run. It is responsible for "exception-safe prefix and
632 : : * suffix operations," although only prefix actions are currently required
633 : : * by the standard. Additional actions may be added by the
634 : : * implementation, and we list them in
635 : : * http://gcc.gnu.org/onlinedocs/libstdc++/17_intro/howto.html#5
636 : : * under [27.6] notes.
637 : : */
638 : : template<typename _CharT, typename _Traits>
639 : : class basic_istream<_CharT, _Traits>::sentry
640 : : {
641 : : public:
642 : : /// Easy access to dependant types.
643 : : typedef _Traits traits_type;
644 : : typedef basic_streambuf<_CharT, _Traits> __streambuf_type;
645 : : typedef basic_istream<_CharT, _Traits> __istream_type;
646 : : typedef typename __istream_type::__ctype_type __ctype_type;
647 : : typedef typename _Traits::int_type __int_type;
648 : :
649 : : /**
650 : : * @brief The constructor performs all the work.
651 : : * @param is The input stream to guard.
652 : : * @param noskipws Whether to consume whitespace or not.
653 : : *
654 : : * If the stream state is good (@a is.good() is true), then the
655 : : * following actions are performed, otherwise the sentry state is
656 : : * false ("not okay") and failbit is set in the stream state.
657 : : *
658 : : * The sentry's preparatory actions are:
659 : : *
660 : : * -# if the stream is tied to an output stream, @c is.tie()->flush()
661 : : * is called to synchronize the output sequence
662 : : * -# if @a noskipws is false, and @c ios_base::skipws is set in
663 : : * @c is.flags(), the sentry extracts and discards whitespace
664 : : * characters from the stream. The currently imbued locale is
665 : : * used to determine whether each character is whitespace.
666 : : *
667 : : * If the stream state is still good, then the sentry state becomes
668 : : * true ("okay").
669 : : */
670 : : explicit
671 : : sentry(basic_istream<_CharT, _Traits>& __is, bool __noskipws = false);
672 : :
673 : : /**
674 : : * @brief Quick status checking.
675 : : * @return The sentry state.
676 : : *
677 : : * For ease of use, sentries may be converted to booleans. The
678 : : * return value is that of the sentry state (true == okay).
679 : : */
680 : : operator bool() const
681 : 0 : { return _M_ok; }
682 : :
683 : : private:
684 : : bool _M_ok;
685 : : };
686 : :
687 : : // [27.6.1.2.3] character extraction templates
688 : : //@{
689 : : /**
690 : : * @brief Character extractors
691 : : * @param in An input stream.
692 : : * @param c A character reference.
693 : : * @return in
694 : : *
695 : : * Behaves like one of the formatted arithmetic extractors described in
696 : : * std::basic_istream. After constructing a sentry object with good
697 : : * status, this function extracts a character (if one is available) and
698 : : * stores it in @a c. Otherwise, sets failbit in the input stream.
699 : : */
700 : : template<typename _CharT, typename _Traits>
701 : : basic_istream<_CharT, _Traits>&
702 : : operator>>(basic_istream<_CharT, _Traits>& __in, _CharT& __c);
703 : :
704 : : template<class _Traits>
705 : : inline basic_istream<char, _Traits>&
706 : : operator>>(basic_istream<char, _Traits>& __in, unsigned char& __c)
707 : : { return (__in >> reinterpret_cast<char&>(__c)); }
708 : :
709 : : template<class _Traits>
710 : : inline basic_istream<char, _Traits>&
711 : : operator>>(basic_istream<char, _Traits>& __in, signed char& __c)
712 : : { return (__in >> reinterpret_cast<char&>(__c)); }
713 : : //@}
714 : :
715 : : //@{
716 : : /**
717 : : * @brief Character string extractors
718 : : * @param in An input stream.
719 : : * @param s A pointer to a character array.
720 : : * @return in
721 : : *
722 : : * Behaves like one of the formatted arithmetic extractors described in
723 : : * std::basic_istream. After constructing a sentry object with good
724 : : * status, this function extracts up to @c n characters and stores them
725 : : * into the array starting at @a s. @c n is defined as:
726 : : *
727 : : * - if @c width() is greater than zero, @c n is width()
728 : : * - otherwise @c n is "the number of elements of the largest array of
729 : : * @c char_type that can store a terminating @c eos." [27.6.1.2.3]/6
730 : : *
731 : : * Characters are extracted and stored until one of the following happens:
732 : : * - @c n-1 characters are stored
733 : : * - EOF is reached
734 : : * - the next character is whitespace according to the current locale
735 : : * - the next character is a null byte (i.e., @c charT() )
736 : : *
737 : : * @c width(0) is then called for the input stream.
738 : : *
739 : : * If no characters are extracted, sets failbit.
740 : : */
741 : : template<typename _CharT, typename _Traits>
742 : : basic_istream<_CharT, _Traits>&
743 : : operator>>(basic_istream<_CharT, _Traits>& __in, _CharT* __s);
744 : :
745 : : // Explicit specialization declaration, defined in src/istream.cc.
746 : : template<>
747 : : basic_istream<char>&
748 : : operator>>(basic_istream<char>& __in, char* __s);
749 : :
750 : : template<class _Traits>
751 : : inline basic_istream<char, _Traits>&
752 : : operator>>(basic_istream<char, _Traits>& __in, unsigned char* __s)
753 : : { return (__in >> reinterpret_cast<char*>(__s)); }
754 : :
755 : : template<class _Traits>
756 : : inline basic_istream<char, _Traits>&
757 : : operator>>(basic_istream<char, _Traits>& __in, signed char* __s)
758 : : { return (__in >> reinterpret_cast<char*>(__s)); }
759 : : //@}
760 : :
761 : : // 27.6.1.5 Template class basic_iostream
762 : : /**
763 : : * @brief Merging istream and ostream capabilities.
764 : : *
765 : : * This class multiply inherits from the input and output stream classes
766 : : * simply to provide a single interface.
767 : : */
768 : : template<typename _CharT, typename _Traits>
769 : : class basic_iostream
770 : : : public basic_istream<_CharT, _Traits>,
771 : : public basic_ostream<_CharT, _Traits>
772 : : {
773 : : public:
774 : : // _GLIBCXX_RESOLVE_LIB_DEFECTS
775 : : // 271. basic_iostream missing typedefs
776 : : // Types (inherited):
777 : : typedef _CharT char_type;
778 : : typedef typename _Traits::int_type int_type;
779 : : typedef typename _Traits::pos_type pos_type;
780 : : typedef typename _Traits::off_type off_type;
781 : : typedef _Traits traits_type;
782 : :
783 : : // Non-standard Types:
784 : : typedef basic_istream<_CharT, _Traits> __istream_type;
785 : : typedef basic_ostream<_CharT, _Traits> __ostream_type;
786 : :
787 : : /**
788 : : * @brief Constructor does nothing.
789 : : *
790 : : * Both of the parent classes are initialized with the same
791 : : * streambuf pointer passed to this constructor.
792 : : */
793 : : explicit
794 : : basic_iostream(basic_streambuf<_CharT, _Traits>* __sb)
795 : : : __istream_type(__sb), __ostream_type(__sb) { }
796 : :
797 : : /**
798 : : * @brief Destructor does nothing.
799 : : */
800 : : virtual
801 [ # # ][ - + ]: 4917 : ~basic_iostream() { }
[ - + ]
802 : :
803 : : protected:
804 : 4917 : basic_iostream()
805 : 4917 : : __istream_type(), __ostream_type() { }
806 : : };
807 : :
808 : : // [27.6.1.4] standard basic_istream manipulators
809 : : /**
810 : : * @brief Quick and easy way to eat whitespace
811 : : *
812 : : * This manipulator extracts whitespace characters, stopping when the
813 : : * next character is non-whitespace, or when the input sequence is empty.
814 : : * If the sequence is empty, @c eofbit is set in the stream, but not
815 : : * @c failbit.
816 : : *
817 : : * The current locale is used to distinguish whitespace characters.
818 : : *
819 : : * Example:
820 : : * @code
821 : : * MyClass mc;
822 : : *
823 : : * std::cin >> std::ws >> mc;
824 : : * @endcode
825 : : * will skip leading whitespace before calling operator>> on cin and your
826 : : * object. Note that the same effect can be achieved by creating a
827 : : * std::basic_istream::sentry inside your definition of operator>>.
828 : : */
829 : : template<typename _CharT, typename _Traits>
830 : : basic_istream<_CharT, _Traits>&
831 : : ws(basic_istream<_CharT, _Traits>& __is);
832 : :
833 : : _GLIBCXX_END_NAMESPACE
834 : :
835 : : #ifndef _GLIBCXX_EXPORT_TEMPLATE
836 : : # include <bits/istream.tcc>
837 : : #endif
838 : :
839 : : #endif /* _GLIBCXX_ISTREAM */
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