1 : // File based 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 : /** @file fstream
33 : * This is a Standard C++ Library header.
34 : */
35 :
36 : //
37 : // ISO C++ 14882: 27.8 File-based streams
38 : //
39 :
40 : #ifndef _GLIBCXX_FSTREAM
41 : #define _GLIBCXX_FSTREAM 1
42 :
43 : #pragma GCC system_header
44 :
45 : #include <istream>
46 : #include <ostream>
47 : #include <bits/codecvt.h>
48 : #include <cstdio> // For BUFSIZ
49 : #include <bits/basic_file.h> // For __basic_file, __c_lock
50 :
51 : _GLIBCXX_BEGIN_NAMESPACE(std)
52 :
53 : // [27.8.1.1] template class basic_filebuf
54 : /**
55 : * @brief The actual work of input and output (for files).
56 : *
57 : * This class associates both its input and output sequence with an
58 : * external disk file, and maintains a joint file position for both
59 : * sequences. Many of its semantics are described in terms of similar
60 : * behavior in the Standard C Library's @c FILE streams.
61 : */
62 : // Requirements on traits_type, specific to this class:
63 : // traits_type::pos_type must be fpos<traits_type::state_type>
64 : // traits_type::off_type must be streamoff
65 : // traits_type::state_type must be Assignable and DefaultConstructible,
66 : // and traits_type::state_type() must be the initial state for codecvt.
67 : template<typename _CharT, typename _Traits>
68 : class basic_filebuf : public basic_streambuf<_CharT, _Traits>
69 : {
70 : public:
71 : // Types:
72 : typedef _CharT char_type;
73 : typedef _Traits traits_type;
74 : typedef typename traits_type::int_type int_type;
75 : typedef typename traits_type::pos_type pos_type;
76 : typedef typename traits_type::off_type off_type;
77 :
78 : typedef basic_streambuf<char_type, traits_type> __streambuf_type;
79 : typedef basic_filebuf<char_type, traits_type> __filebuf_type;
80 : typedef __basic_file<char> __file_type;
81 : typedef typename traits_type::state_type __state_type;
82 : typedef codecvt<char_type, char, __state_type> __codecvt_type;
83 :
84 : friend class ios_base; // For sync_with_stdio.
85 :
86 : protected:
87 : // Data Members:
88 : // MT lock inherited from libio or other low-level io library.
89 : __c_lock _M_lock;
90 :
91 : // External buffer.
92 : __file_type _M_file;
93 :
94 : /// Place to stash in || out || in | out settings for current filebuf.
95 : ios_base::openmode _M_mode;
96 :
97 : // Beginning state type for codecvt.
98 : __state_type _M_state_beg;
99 :
100 : // During output, the state that corresponds to pptr(),
101 : // during input, the state that corresponds to egptr() and
102 : // _M_ext_next.
103 : __state_type _M_state_cur;
104 :
105 : // Not used for output. During input, the state that corresponds
106 : // to eback() and _M_ext_buf.
107 : __state_type _M_state_last;
108 :
109 : /// Pointer to the beginning of internal buffer.
110 : char_type* _M_buf;
111 :
112 : /**
113 : * Actual size of internal buffer. This number is equal to the size
114 : * of the put area + 1 position, reserved for the overflow char of
115 : * a full area.
116 : */
117 : size_t _M_buf_size;
118 :
119 : // Set iff _M_buf is allocated memory from _M_allocate_internal_buffer.
120 : bool _M_buf_allocated;
121 :
122 : /**
123 : * _M_reading == false && _M_writing == false for 'uncommitted' mode;
124 : * _M_reading == true for 'read' mode;
125 : * _M_writing == true for 'write' mode;
126 : *
127 : * NB: _M_reading == true && _M_writing == true is unused.
128 : */
129 : bool _M_reading;
130 : bool _M_writing;
131 :
132 : //@{
133 : /**
134 : * Necessary bits for putback buffer management.
135 : *
136 : * @note pbacks of over one character are not currently supported.
137 : */
138 : char_type _M_pback;
139 : char_type* _M_pback_cur_save;
140 : char_type* _M_pback_end_save;
141 : bool _M_pback_init;
142 : //@}
143 :
144 : // Cached codecvt facet.
145 : const __codecvt_type* _M_codecvt;
146 :
147 : /**
148 : * Buffer for external characters. Used for input when
149 : * codecvt::always_noconv() == false. When valid, this corresponds
150 : * to eback().
151 : */
152 : char* _M_ext_buf;
153 :
154 : /**
155 : * Size of buffer held by _M_ext_buf.
156 : */
157 : streamsize _M_ext_buf_size;
158 :
159 : /**
160 : * Pointers into the buffer held by _M_ext_buf that delimit a
161 : * subsequence of bytes that have been read but not yet converted.
162 : * When valid, _M_ext_next corresponds to egptr().
163 : */
164 : const char* _M_ext_next;
165 : char* _M_ext_end;
166 :
167 : /**
168 : * Initializes pback buffers, and moves normal buffers to safety.
169 : * Assumptions:
170 : * _M_in_cur has already been moved back
171 : */
172 : void
173 : _M_create_pback()
174 : {
175 : if (!_M_pback_init)
176 : {
177 : _M_pback_cur_save = this->gptr();
178 : _M_pback_end_save = this->egptr();
179 : this->setg(&_M_pback, &_M_pback, &_M_pback + 1);
180 : _M_pback_init = true;
181 : }
182 : }
183 :
184 : /**
185 : * Deactivates pback buffer contents, and restores normal buffer.
186 : * Assumptions:
187 : * The pback buffer has only moved forward.
188 : */
189 : void
190 : _M_destroy_pback() throw()
191 : {
192 : if (_M_pback_init)
193 : {
194 : // Length _M_in_cur moved in the pback buffer.
195 : _M_pback_cur_save += this->gptr() != this->eback();
196 : this->setg(_M_buf, _M_pback_cur_save, _M_pback_end_save);
197 : _M_pback_init = false;
198 : }
199 : }
200 :
201 : public:
202 : // Constructors/destructor:
203 : /**
204 : * @brief Does not open any files.
205 : *
206 : * The default constructor initializes the parent class using its
207 : * own default ctor.
208 : */
209 : basic_filebuf();
210 :
211 : /**
212 : * @brief The destructor closes the file first.
213 : */
214 : virtual
215 0 : ~basic_filebuf()
216 0 : { this->close(); }
217 :
218 : // Members:
219 : /**
220 : * @brief Returns true if the external file is open.
221 : */
222 : bool
223 0 : is_open() const throw()
224 0 : { return _M_file.is_open(); }
225 :
226 : /**
227 : * @brief Opens an external file.
228 : * @param s The name of the file.
229 : * @param mode The open mode flags.
230 : * @return @c this on success, NULL on failure
231 : *
232 : * If a file is already open, this function immediately fails.
233 : * Otherwise it tries to open the file named @a s using the flags
234 : * given in @a mode.
235 : *
236 : * Table 92, adapted here, gives the relation between openmode
237 : * combinations and the equivalent fopen() flags.
238 : * (NB: lines app, in|out|app, in|app, binary|app, binary|in|out|app,
239 : * and binary|in|app per DR 596)
240 : * +---------------------------------------------------------+
241 : * | ios_base Flag combination stdio equivalent |
242 : * |binary in out trunc app |
243 : * +---------------------------------------------------------+
244 : * | + "w" |
245 : * | + + "a" |
246 : * | + "a" |
247 : * | + + "w" |
248 : * | + "r" |
249 : * | + + "r+" |
250 : * | + + + "w+" |
251 : * | + + + "a+" |
252 : * | + + "a+" |
253 : * +---------------------------------------------------------+
254 : * | + + "wb" |
255 : * | + + + "ab" |
256 : * | + + "ab" |
257 : * | + + + "wb" |
258 : * | + + "rb" |
259 : * | + + + "r+b" |
260 : * | + + + + "w+b" |
261 : * | + + + + "a+b" |
262 : * | + + + "a+b" |
263 : * +---------------------------------------------------------+
264 : */
265 : __filebuf_type*
266 : open(const char* __s, ios_base::openmode __mode);
267 :
268 : /**
269 : * @brief Closes the currently associated file.
270 : * @return @c this on success, NULL on failure
271 : *
272 : * If no file is currently open, this function immediately fails.
273 : *
274 : * If a "put buffer area" exists, @c overflow(eof) is called to flush
275 : * all the characters. The file is then closed.
276 : *
277 : * If any operations fail, this function also fails.
278 : */
279 : __filebuf_type*
280 : close();
281 :
282 : protected:
283 : void
284 : _M_allocate_internal_buffer();
285 :
286 : void
287 : _M_destroy_internal_buffer() throw();
288 :
289 : // [27.8.1.4] overridden virtual functions
290 : virtual streamsize
291 : showmanyc();
292 :
293 : // Stroustrup, 1998, p. 628
294 : // underflow() and uflow() functions are called to get the next
295 : // character from the real input source when the buffer is empty.
296 : // Buffered input uses underflow()
297 :
298 : virtual int_type
299 : underflow();
300 :
301 : virtual int_type
302 : pbackfail(int_type __c = _Traits::eof());
303 :
304 : // Stroustrup, 1998, p 648
305 : // The overflow() function is called to transfer characters to the
306 : // real output destination when the buffer is full. A call to
307 : // overflow(c) outputs the contents of the buffer plus the
308 : // character c.
309 : // 27.5.2.4.5
310 : // Consume some sequence of the characters in the pending sequence.
311 : virtual int_type
312 : overflow(int_type __c = _Traits::eof());
313 :
314 : // Convert internal byte sequence to external, char-based
315 : // sequence via codecvt.
316 : bool
317 : _M_convert_to_external(char_type*, streamsize);
318 :
319 : /**
320 : * @brief Manipulates the buffer.
321 : * @param s Pointer to a buffer area.
322 : * @param n Size of @a s.
323 : * @return @c this
324 : *
325 : * If no file has been opened, and both @a s and @a n are zero, then
326 : * the stream becomes unbuffered. Otherwise, @c s is used as a
327 : * buffer; see
328 : * http://gcc.gnu.org/onlinedocs/libstdc++/27_io/howto.html#2
329 : * for more.
330 : */
331 : virtual __streambuf_type*
332 : setbuf(char_type* __s, streamsize __n);
333 :
334 : virtual pos_type
335 : seekoff(off_type __off, ios_base::seekdir __way,
336 : ios_base::openmode __mode = ios_base::in | ios_base::out);
337 :
338 : virtual pos_type
339 : seekpos(pos_type __pos,
340 : ios_base::openmode __mode = ios_base::in | ios_base::out);
341 :
342 : // Common code for seekoff and seekpos
343 : pos_type
344 : _M_seek(off_type __off, ios_base::seekdir __way, __state_type __state);
345 :
346 : virtual int
347 : sync();
348 :
349 : virtual void
350 : imbue(const locale& __loc);
351 :
352 : virtual streamsize
353 : xsgetn(char_type* __s, streamsize __n);
354 :
355 : virtual streamsize
356 : xsputn(const char_type* __s, streamsize __n);
357 :
358 : // Flushes output buffer, then writes unshift sequence.
359 : bool
360 : _M_terminate_output();
361 :
362 : /**
363 : * This function sets the pointers of the internal buffer, both get
364 : * and put areas. Typically:
365 : *
366 : * __off == egptr() - eback() upon underflow/uflow ('read' mode);
367 : * __off == 0 upon overflow ('write' mode);
368 : * __off == -1 upon open, setbuf, seekoff/pos ('uncommitted' mode).
369 : *
370 : * NB: epptr() - pbase() == _M_buf_size - 1, since _M_buf_size
371 : * reflects the actual allocated memory and the last cell is reserved
372 : * for the overflow char of a full put area.
373 : */
374 : void
375 : _M_set_buffer(streamsize __off)
376 : {
377 : const bool __testin = _M_mode & ios_base::in;
378 : const bool __testout = _M_mode & ios_base::out;
379 :
380 : if (__testin && __off > 0)
381 : this->setg(_M_buf, _M_buf, _M_buf + __off);
382 : else
383 : this->setg(_M_buf, _M_buf, _M_buf);
384 :
385 : if (__testout && __off == 0 && _M_buf_size > 1 )
386 : this->setp(_M_buf, _M_buf + _M_buf_size - 1);
387 : else
388 : this->setp(NULL, NULL);
389 : }
390 : };
391 :
392 : // [27.8.1.5] Template class basic_ifstream
393 : /**
394 : * @brief Controlling input for files.
395 : *
396 : * This class supports reading from named files, using the inherited
397 : * functions from std::basic_istream. To control the associated
398 : * sequence, an instance of std::basic_filebuf is used, which this page
399 : * refers to as @c sb.
400 : */
401 : template<typename _CharT, typename _Traits>
402 : class basic_ifstream : public basic_istream<_CharT, _Traits>
403 : {
404 : public:
405 : // Types:
406 : typedef _CharT char_type;
407 : typedef _Traits traits_type;
408 : typedef typename traits_type::int_type int_type;
409 : typedef typename traits_type::pos_type pos_type;
410 : typedef typename traits_type::off_type off_type;
411 :
412 : // Non-standard types:
413 : typedef basic_filebuf<char_type, traits_type> __filebuf_type;
414 : typedef basic_istream<char_type, traits_type> __istream_type;
415 :
416 : private:
417 : __filebuf_type _M_filebuf;
418 :
419 : public:
420 : // Constructors/Destructors:
421 : /**
422 : * @brief Default constructor.
423 : *
424 : * Initializes @c sb using its default constructor, and passes
425 : * @c &sb to the base class initializer. Does not open any files
426 : * (you haven't given it a filename to open).
427 : */
428 0 : basic_ifstream() : __istream_type(), _M_filebuf()
429 0 : { this->init(&_M_filebuf); }
430 :
431 : /**
432 : * @brief Create an input file stream.
433 : * @param s Null terminated string specifying the filename.
434 : * @param mode Open file in specified mode (see std::ios_base).
435 : *
436 : * @c ios_base::in is automatically included in @a mode.
437 : *
438 : * Tip: When using std::string to hold the filename, you must use
439 : * .c_str() before passing it to this constructor.
440 : */
441 : explicit
442 0 : basic_ifstream(const char* __s, ios_base::openmode __mode = ios_base::in)
443 0 : : __istream_type(), _M_filebuf()
444 : {
445 0 : this->init(&_M_filebuf);
446 0 : this->open(__s, __mode);
447 0 : }
448 :
449 : /**
450 : * @brief The destructor does nothing.
451 : *
452 : * The file is closed by the filebuf object, not the formatting
453 : * stream.
454 : */
455 0 : ~basic_ifstream()
456 0 : { }
457 :
458 : // Members:
459 : /**
460 : * @brief Accessing the underlying buffer.
461 : * @return The current basic_filebuf buffer.
462 : *
463 : * This hides both signatures of std::basic_ios::rdbuf().
464 : */
465 : __filebuf_type*
466 : rdbuf() const
467 : { return const_cast<__filebuf_type*>(&_M_filebuf); }
468 :
469 : /**
470 : * @brief Wrapper to test for an open file.
471 : * @return @c rdbuf()->is_open()
472 : */
473 : bool
474 0 : is_open()
475 0 : { return _M_filebuf.is_open(); }
476 :
477 : // _GLIBCXX_RESOLVE_LIB_DEFECTS
478 : // 365. Lack of const-qualification in clause 27
479 : bool
480 : is_open() const
481 : { return _M_filebuf.is_open(); }
482 :
483 : /**
484 : * @brief Opens an external file.
485 : * @param s The name of the file.
486 : * @param mode The open mode flags.
487 : *
488 : * Calls @c std::basic_filebuf::open(s,mode|in). If that function
489 : * fails, @c failbit is set in the stream's error state.
490 : *
491 : * Tip: When using std::string to hold the filename, you must use
492 : * .c_str() before passing it to this constructor.
493 : */
494 : void
495 0 : open(const char* __s, ios_base::openmode __mode = ios_base::in)
496 : {
497 0 : if (!_M_filebuf.open(__s, __mode | ios_base::in))
498 0 : this->setstate(ios_base::failbit);
499 : else
500 : // _GLIBCXX_RESOLVE_LIB_DEFECTS
501 : // 409. Closing an fstream should clear error state
502 0 : this->clear();
503 0 : }
504 :
505 : /**
506 : * @brief Close the file.
507 : *
508 : * Calls @c std::basic_filebuf::close(). If that function
509 : * fails, @c failbit is set in the stream's error state.
510 : */
511 : void
512 0 : close()
513 : {
514 0 : if (!_M_filebuf.close())
515 0 : this->setstate(ios_base::failbit);
516 0 : }
517 : };
518 :
519 :
520 : // [27.8.1.8] Template class basic_ofstream
521 : /**
522 : * @brief Controlling output for files.
523 : *
524 : * This class supports reading from named files, using the inherited
525 : * functions from std::basic_ostream. To control the associated
526 : * sequence, an instance of std::basic_filebuf is used, which this page
527 : * refers to as @c sb.
528 : */
529 : template<typename _CharT, typename _Traits>
530 : class basic_ofstream : public basic_ostream<_CharT,_Traits>
531 : {
532 : public:
533 : // Types:
534 : typedef _CharT char_type;
535 : typedef _Traits traits_type;
536 : typedef typename traits_type::int_type int_type;
537 : typedef typename traits_type::pos_type pos_type;
538 : typedef typename traits_type::off_type off_type;
539 :
540 : // Non-standard types:
541 : typedef basic_filebuf<char_type, traits_type> __filebuf_type;
542 : typedef basic_ostream<char_type, traits_type> __ostream_type;
543 :
544 : private:
545 : __filebuf_type _M_filebuf;
546 :
547 : public:
548 : // Constructors:
549 : /**
550 : * @brief Default constructor.
551 : *
552 : * Initializes @c sb using its default constructor, and passes
553 : * @c &sb to the base class initializer. Does not open any files
554 : * (you haven't given it a filename to open).
555 : */
556 : basic_ofstream(): __ostream_type(), _M_filebuf()
557 : { this->init(&_M_filebuf); }
558 :
559 : /**
560 : * @brief Create an output file stream.
561 : * @param s Null terminated string specifying the filename.
562 : * @param mode Open file in specified mode (see std::ios_base).
563 : *
564 : * @c ios_base::out|ios_base::trunc is automatically included in
565 : * @a mode.
566 : *
567 : * Tip: When using std::string to hold the filename, you must use
568 : * .c_str() before passing it to this constructor.
569 : */
570 : explicit
571 : basic_ofstream(const char* __s,
572 0 : ios_base::openmode __mode = ios_base::out|ios_base::trunc)
573 0 : : __ostream_type(), _M_filebuf()
574 : {
575 0 : this->init(&_M_filebuf);
576 0 : this->open(__s, __mode);
577 0 : }
578 :
579 : /**
580 : * @brief The destructor does nothing.
581 : *
582 : * The file is closed by the filebuf object, not the formatting
583 : * stream.
584 : */
585 0 : ~basic_ofstream()
586 0 : { }
587 :
588 : // Members:
589 : /**
590 : * @brief Accessing the underlying buffer.
591 : * @return The current basic_filebuf buffer.
592 : *
593 : * This hides both signatures of std::basic_ios::rdbuf().
594 : */
595 : __filebuf_type*
596 : rdbuf() const
597 : { return const_cast<__filebuf_type*>(&_M_filebuf); }
598 :
599 : /**
600 : * @brief Wrapper to test for an open file.
601 : * @return @c rdbuf()->is_open()
602 : */
603 : bool
604 0 : is_open()
605 0 : { return _M_filebuf.is_open(); }
606 :
607 : // _GLIBCXX_RESOLVE_LIB_DEFECTS
608 : // 365. Lack of const-qualification in clause 27
609 : bool
610 : is_open() const
611 : { return _M_filebuf.is_open(); }
612 :
613 : /**
614 : * @brief Opens an external file.
615 : * @param s The name of the file.
616 : * @param mode The open mode flags.
617 : *
618 : * Calls @c std::basic_filebuf::open(s,mode|out|trunc). If that
619 : * function fails, @c failbit is set in the stream's error state.
620 : *
621 : * Tip: When using std::string to hold the filename, you must use
622 : * .c_str() before passing it to this constructor.
623 : */
624 : void
625 : open(const char* __s,
626 0 : ios_base::openmode __mode = ios_base::out | ios_base::trunc)
627 : {
628 0 : if (!_M_filebuf.open(__s, __mode | ios_base::out))
629 0 : this->setstate(ios_base::failbit);
630 : else
631 : // _GLIBCXX_RESOLVE_LIB_DEFECTS
632 : // 409. Closing an fstream should clear error state
633 0 : this->clear();
634 0 : }
635 :
636 : /**
637 : * @brief Close the file.
638 : *
639 : * Calls @c std::basic_filebuf::close(). If that function
640 : * fails, @c failbit is set in the stream's error state.
641 : */
642 : void
643 : close()
644 : {
645 : if (!_M_filebuf.close())
646 : this->setstate(ios_base::failbit);
647 : }
648 : };
649 :
650 :
651 : // [27.8.1.11] Template class basic_fstream
652 : /**
653 : * @brief Controlling input and output for files.
654 : *
655 : * This class supports reading from and writing to named files, using
656 : * the inherited functions from std::basic_iostream. To control the
657 : * associated sequence, an instance of std::basic_filebuf is used, which
658 : * this page refers to as @c sb.
659 : */
660 : template<typename _CharT, typename _Traits>
661 : class basic_fstream : public basic_iostream<_CharT, _Traits>
662 : {
663 : public:
664 : // Types:
665 : typedef _CharT char_type;
666 : typedef _Traits traits_type;
667 : typedef typename traits_type::int_type int_type;
668 : typedef typename traits_type::pos_type pos_type;
669 : typedef typename traits_type::off_type off_type;
670 :
671 : // Non-standard types:
672 : typedef basic_filebuf<char_type, traits_type> __filebuf_type;
673 : typedef basic_ios<char_type, traits_type> __ios_type;
674 : typedef basic_iostream<char_type, traits_type> __iostream_type;
675 :
676 : private:
677 : __filebuf_type _M_filebuf;
678 :
679 : public:
680 : // Constructors/destructor:
681 : /**
682 : * @brief Default constructor.
683 : *
684 : * Initializes @c sb using its default constructor, and passes
685 : * @c &sb to the base class initializer. Does not open any files
686 : * (you haven't given it a filename to open).
687 : */
688 : basic_fstream()
689 : : __iostream_type(), _M_filebuf()
690 : { this->init(&_M_filebuf); }
691 :
692 : /**
693 : * @brief Create an input/output file stream.
694 : * @param s Null terminated string specifying the filename.
695 : * @param mode Open file in specified mode (see std::ios_base).
696 : *
697 : * Tip: When using std::string to hold the filename, you must use
698 : * .c_str() before passing it to this constructor.
699 : */
700 : explicit
701 : basic_fstream(const char* __s,
702 : ios_base::openmode __mode = ios_base::in | ios_base::out)
703 : : __iostream_type(NULL), _M_filebuf()
704 : {
705 : this->init(&_M_filebuf);
706 : this->open(__s, __mode);
707 : }
708 :
709 : /**
710 : * @brief The destructor does nothing.
711 : *
712 : * The file is closed by the filebuf object, not the formatting
713 : * stream.
714 : */
715 : ~basic_fstream()
716 : { }
717 :
718 : // Members:
719 : /**
720 : * @brief Accessing the underlying buffer.
721 : * @return The current basic_filebuf buffer.
722 : *
723 : * This hides both signatures of std::basic_ios::rdbuf().
724 : */
725 : __filebuf_type*
726 : rdbuf() const
727 : { return const_cast<__filebuf_type*>(&_M_filebuf); }
728 :
729 : /**
730 : * @brief Wrapper to test for an open file.
731 : * @return @c rdbuf()->is_open()
732 : */
733 : bool
734 : is_open()
735 : { return _M_filebuf.is_open(); }
736 :
737 : // _GLIBCXX_RESOLVE_LIB_DEFECTS
738 : // 365. Lack of const-qualification in clause 27
739 : bool
740 : is_open() const
741 : { return _M_filebuf.is_open(); }
742 :
743 : /**
744 : * @brief Opens an external file.
745 : * @param s The name of the file.
746 : * @param mode The open mode flags.
747 : *
748 : * Calls @c std::basic_filebuf::open(s,mode). If that
749 : * function fails, @c failbit is set in the stream's error state.
750 : *
751 : * Tip: When using std::string to hold the filename, you must use
752 : * .c_str() before passing it to this constructor.
753 : */
754 : void
755 : open(const char* __s,
756 : ios_base::openmode __mode = ios_base::in | ios_base::out)
757 : {
758 : if (!_M_filebuf.open(__s, __mode))
759 : this->setstate(ios_base::failbit);
760 : else
761 : // _GLIBCXX_RESOLVE_LIB_DEFECTS
762 : // 409. Closing an fstream should clear error state
763 : this->clear();
764 : }
765 :
766 : /**
767 : * @brief Close the file.
768 : *
769 : * Calls @c std::basic_filebuf::close(). If that function
770 : * fails, @c failbit is set in the stream's error state.
771 : */
772 : void
773 : close()
774 : {
775 : if (!_M_filebuf.close())
776 : this->setstate(ios_base::failbit);
777 : }
778 : };
779 :
780 : _GLIBCXX_END_NAMESPACE
781 :
782 : #ifndef _GLIBCXX_EXPORT_TEMPLATE
783 : # include <bits/fstream.tcc>
784 : #endif
785 :
786 : #endif /* _GLIBCXX_FSTREAM */
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