1// String based streams -*- 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 include/sstream
26 * This is a Standard C++ Library header.
27 */
28
29//
30// ISO C++ 14882: 27.7 String-based streams
31//
32
33#ifndef _GLIBCXX_SSTREAM
34#define _GLIBCXX_SSTREAM 1
35
36#pragma GCC system_header
37
38#include <istream>
39#include <ostream>
40
41namespace std _GLIBCXX_VISIBILITY(default)
42{
43_GLIBCXX_BEGIN_NAMESPACE_VERSION
44_GLIBCXX_BEGIN_NAMESPACE_CXX11
45
46 // [27.7.1] template class basic_stringbuf
47 /**
48 * @brief The actual work of input and output (for std::string).
49 * @ingroup io
50 *
51 * @tparam _CharT Type of character stream.
52 * @tparam _Traits Traits for character type, defaults to
53 * char_traits<_CharT>.
54 * @tparam _Alloc Allocator type, defaults to allocator<_CharT>.
55 *
56 * This class associates either or both of its input and output sequences
57 * with a sequence of characters, which can be initialized from, or made
58 * available as, a @c std::basic_string. (Paraphrased from [27.7.1]/1.)
59 *
60 * For this class, open modes (of type @c ios_base::openmode) have
61 * @c in set if the input sequence can be read, and @c out set if the
62 * output sequence can be written.
63 */
64 template<typename _CharT, typename _Traits, typename _Alloc>
65 class basic_stringbuf : public basic_streambuf<_CharT, _Traits>
66 {
67 struct __xfer_bufptrs;
68 public:
69 // Types:
70 typedef _CharT char_type;
71 typedef _Traits traits_type;
72 // _GLIBCXX_RESOLVE_LIB_DEFECTS
73 // 251. basic_stringbuf missing allocator_type
74 typedef _Alloc allocator_type;
75 typedef typename traits_type::int_type int_type;
76 typedef typename traits_type::pos_type pos_type;
77 typedef typename traits_type::off_type off_type;
78
79 typedef basic_streambuf<char_type, traits_type> __streambuf_type;
80 typedef basic_string<char_type, _Traits, _Alloc> __string_type;
81 typedef typename __string_type::size_type __size_type;
82
83 protected:
84 /// Place to stash in || out || in | out settings for current stringbuf.
85 ios_base::openmode _M_mode;
86
87 // Data Members:
88 __string_type _M_string;
89
90 public:
91 // Constructors:
92 /**
93 * @brief Starts with an empty string buffer.
94 * @param __mode Whether the buffer can read, or write, or both.
95 *
96 * The default constructor initializes the parent class using its
97 * own default ctor.
98 */
99 explicit
100 basic_stringbuf(ios_base::openmode __mode = ios_base::in | ios_base::out)
101 : __streambuf_type(), _M_mode(__mode), _M_string()
102 { }
103
104 /**
105 * @brief Starts with an existing string buffer.
106 * @param __str A string to copy as a starting buffer.
107 * @param __mode Whether the buffer can read, or write, or both.
108 *
109 * This constructor initializes the parent class using its
110 * own default ctor.
111 */
112 explicit
113 basic_stringbuf(const __string_type& __str,
114 ios_base::openmode __mode = ios_base::in | ios_base::out)
115 : __streambuf_type(), _M_mode(),
116 _M_string(__str.data(), __str.size(), __str.get_allocator())
117 { _M_stringbuf_init(__mode); }
118
119#if __cplusplus >= 201103L
120 basic_stringbuf(const basic_stringbuf&) = delete;
121
122 basic_stringbuf(basic_stringbuf&& __rhs)
123 : basic_stringbuf(std::move(__rhs), __xfer_bufptrs(__rhs, this))
124 { __rhs._M_sync(const_cast<char_type*>(__rhs._M_string.data()), 0, 0); }
125
126 // 27.8.2.2 Assign and swap:
127
128 basic_stringbuf&
129 operator=(const basic_stringbuf&) = delete;
130
131 basic_stringbuf&
132 operator=(basic_stringbuf&& __rhs)
133 {
134 __xfer_bufptrs __st{__rhs, this};
135 const __streambuf_type& __base = __rhs;
136 __streambuf_type::operator=(__base);
137 this->pubimbue(__rhs.getloc());
138 _M_mode = __rhs._M_mode;
139 _M_string = std::move(__rhs._M_string);
140 __rhs._M_sync(const_cast<char_type*>(__rhs._M_string.data()), 0, 0);
141 return *this;
142 }
143
144 void
145 swap(basic_stringbuf& __rhs)
146 {
147 __xfer_bufptrs __l_st{*this, std::__addressof(__rhs)};
148 __xfer_bufptrs __r_st{__rhs, this};
149 __streambuf_type& __base = __rhs;
150 __streambuf_type::swap(__base);
151 __rhs.pubimbue(this->pubimbue(__rhs.getloc()));
152 std::swap(_M_mode, __rhs._M_mode);
153 std::swap(_M_string, __rhs._M_string);
154 }
155#endif
156
157 // Get and set:
158 /**
159 * @brief Copying out the string buffer.
160 * @return A copy of one of the underlying sequences.
161 *
162 * <em>If the buffer is only created in input mode, the underlying
163 * character sequence is equal to the input sequence; otherwise, it
164 * is equal to the output sequence.</em> [27.7.1.2]/1
165 */
166 __string_type
167 str() const
168 {
169 __string_type __ret(_M_string.get_allocator());
170 if (this->pptr())
171 {
172 // The current egptr() may not be the actual string end.
173 if (this->pptr() > this->egptr())
174 __ret.assign(this->pbase(), this->pptr());
175 else
176 __ret.assign(this->pbase(), this->egptr());
177 }
178 else
179 __ret = _M_string;
180 return __ret;
181 }
182
183 /**
184 * @brief Setting a new buffer.
185 * @param __s The string to use as a new sequence.
186 *
187 * Deallocates any previous stored sequence, then copies @a s to
188 * use as a new one.
189 */
190 void
191 str(const __string_type& __s)
192 {
193 // Cannot use _M_string = __s, since v3 strings are COW
194 // (not always true now but assign() always works).
195 _M_string.assign(__s.data(), __s.size());
196 _M_stringbuf_init(_M_mode);
197 }
198
199 protected:
200 // Common initialization code goes here.
201 void
202 _M_stringbuf_init(ios_base::openmode __mode)
203 {
204 _M_mode = __mode;
205 __size_type __len = 0;
206 if (_M_mode & (ios_base::ate | ios_base::app))
207 __len = _M_string.size();
208 _M_sync(const_cast<char_type*>(_M_string.data()), 0, __len);
209 }
210
211 virtual streamsize
212 showmanyc()
213 {
214 streamsize __ret = -1;
215 if (_M_mode & ios_base::in)
216 {
217 _M_update_egptr();
218 __ret = this->egptr() - this->gptr();
219 }
220 return __ret;
221 }
222
223 virtual int_type
224 underflow();
225
226 virtual int_type
227 pbackfail(int_type __c = traits_type::eof());
228
229 virtual int_type
230 overflow(int_type __c = traits_type::eof());
231
232 /**
233 * @brief Manipulates the buffer.
234 * @param __s Pointer to a buffer area.
235 * @param __n Size of @a __s.
236 * @return @c this
237 *
238 * If no buffer has already been created, and both @a __s and @a __n are
239 * non-zero, then @c __s is used as a buffer; see
240 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/streambufs.html#io.streambuf.buffering
241 * for more.
242 */
243 virtual __streambuf_type*
244 setbuf(char_type* __s, streamsize __n)
245 {
246 if (__s && __n >= 0)
247 {
248 // This is implementation-defined behavior, and assumes
249 // that an external char_type array of length __n exists
250 // and has been pre-allocated. If this is not the case,
251 // things will quickly blow up.
252
253 // Step 1: Destroy the current internal array.
254 _M_string.clear();
255
256 // Step 2: Use the external array.
257 _M_sync(__s, __n, 0);
258 }
259 return this;
260 }
261
262 virtual pos_type
263 seekoff(off_type __off, ios_base::seekdir __way,
264 ios_base::openmode __mode = ios_base::in | ios_base::out);
265
266 virtual pos_type
267 seekpos(pos_type __sp,
268 ios_base::openmode __mode = ios_base::in | ios_base::out);
269
270 // Internal function for correctly updating the internal buffer
271 // for a particular _M_string, due to initialization or re-sizing
272 // of an existing _M_string.
273 void
274 _M_sync(char_type* __base, __size_type __i, __size_type __o);
275
276 // Internal function for correctly updating egptr() to the actual
277 // string end.
278 void
279 _M_update_egptr()
280 {
281 const bool __testin = _M_mode & ios_base::in;
282 if (this->pptr() && this->pptr() > this->egptr())
283 {
284 if (__testin)
285 this->setg(this->eback(), this->gptr(), this->pptr());
286 else
287 this->setg(this->pptr(), this->pptr(), this->pptr());
288 }
289 }
290
291 // Works around the issue with pbump, part of the protected
292 // interface of basic_streambuf, taking just an int.
293 void
294 _M_pbump(char_type* __pbeg, char_type* __pend, off_type __off);
295
296 private:
297#if __cplusplus >= 201103L
298#if _GLIBCXX_USE_CXX11_ABI
299 // This type captures the state of the gptr / pptr pointers as offsets
300 // so they can be restored in another object after moving the string.
301 struct __xfer_bufptrs
302 {
303 __xfer_bufptrs(const basic_stringbuf& __from, basic_stringbuf* __to)
304 : _M_to{__to}, _M_goff{-1, -1, -1}, _M_poff{-1, -1, -1}
305 {
306 const _CharT* const __str = __from._M_string.data();
307 const _CharT* __end = nullptr;
308 if (__from.eback())
309 {
310 _M_goff[0] = __from.eback() - __str;
311 _M_goff[1] = __from.gptr() - __str;
312 _M_goff[2] = __from.egptr() - __str;
313 __end = __from.egptr();
314 }
315 if (__from.pbase())
316 {
317 _M_poff[0] = __from.pbase() - __str;
318 _M_poff[1] = __from.pptr() - __from.pbase();
319 _M_poff[2] = __from.epptr() - __str;
320 if (__from.pptr() > __end)
321 __end = __from.pptr();
322 }
323
324 // Set _M_string length to the greater of the get and put areas.
325 if (__end)
326 {
327 // The const_cast avoids changing this constructor's signature,
328 // because it is exported from the dynamic library.
329 auto& __mut_from = const_cast<basic_stringbuf&>(__from);
330 __mut_from._M_string._M_length(__end - __str);
331 }
332 }
333
334 ~__xfer_bufptrs()
335 {
336 char_type* __str = const_cast<char_type*>(_M_to->_M_string.data());
337 if (_M_goff[0] != -1)
338 _M_to->setg(__str+_M_goff[0], __str+_M_goff[1], __str+_M_goff[2]);
339 if (_M_poff[0] != -1)
340 _M_to->_M_pbump(__str+_M_poff[0], __str+_M_poff[2], _M_poff[1]);
341 }
342
343 basic_stringbuf* _M_to;
344 off_type _M_goff[3];
345 off_type _M_poff[3];
346 };
347#else
348 // This type does nothing when using Copy-On-Write strings.
349 struct __xfer_bufptrs
350 {
351 __xfer_bufptrs(const basic_stringbuf&, basic_stringbuf*) { }
352 };
353#endif
354
355 // The move constructor initializes an __xfer_bufptrs temporary then
356 // delegates to this constructor to performs moves during its lifetime.
357 basic_stringbuf(basic_stringbuf&& __rhs, __xfer_bufptrs&&)
358 : __streambuf_type(static_cast<const __streambuf_type&>(__rhs)),
359 _M_mode(__rhs._M_mode), _M_string(std::move(__rhs._M_string))
360 { }
361#endif
362 };
363
364
365 // [27.7.2] Template class basic_istringstream
366 /**
367 * @brief Controlling input for std::string.
368 * @ingroup io
369 *
370 * @tparam _CharT Type of character stream.
371 * @tparam _Traits Traits for character type, defaults to
372 * char_traits<_CharT>.
373 * @tparam _Alloc Allocator type, defaults to allocator<_CharT>.
374 *
375 * This class supports reading from objects of type std::basic_string,
376 * using the inherited functions from std::basic_istream. To control
377 * the associated sequence, an instance of std::basic_stringbuf is used,
378 * which this page refers to as @c sb.
379 */
380 template<typename _CharT, typename _Traits, typename _Alloc>
381 class basic_istringstream : public basic_istream<_CharT, _Traits>
382 {
383 public:
384 // Types:
385 typedef _CharT char_type;
386 typedef _Traits traits_type;
387 // _GLIBCXX_RESOLVE_LIB_DEFECTS
388 // 251. basic_stringbuf missing allocator_type
389 typedef _Alloc allocator_type;
390 typedef typename traits_type::int_type int_type;
391 typedef typename traits_type::pos_type pos_type;
392 typedef typename traits_type::off_type off_type;
393
394 // Non-standard types:
395 typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
396 typedef basic_stringbuf<_CharT, _Traits, _Alloc> __stringbuf_type;
397 typedef basic_istream<char_type, traits_type> __istream_type;
398
399 private:
400 __stringbuf_type _M_stringbuf;
401
402 public:
403 // Constructors:
404 /**
405 * @brief Default constructor starts with an empty string buffer.
406 * @param __mode Whether the buffer can read, or write, or both.
407 *
408 * @c ios_base::in is automatically included in @a __mode.
409 *
410 * Initializes @c sb using @c __mode|in, and passes @c &sb to the base
411 * class initializer. Does not allocate any buffer.
412 *
413 * That's a lie. We initialize the base class with NULL, because the
414 * string class does its own memory management.
415 */
416 explicit
417 basic_istringstream(ios_base::openmode __mode = ios_base::in)
418 : __istream_type(), _M_stringbuf(__mode | ios_base::in)
419 { this->init(&_M_stringbuf); }
420
421 /**
422 * @brief Starts with an existing string buffer.
423 * @param __str A string to copy as a starting buffer.
424 * @param __mode Whether the buffer can read, or write, or both.
425 *
426 * @c ios_base::in is automatically included in @a mode.
427 *
428 * Initializes @c sb using @a str and @c mode|in, and passes @c &sb
429 * to the base class initializer.
430 *
431 * That's a lie. We initialize the base class with NULL, because the
432 * string class does its own memory management.
433 */
434 explicit
435 basic_istringstream(const __string_type& __str,
436 ios_base::openmode __mode = ios_base::in)
437 : __istream_type(), _M_stringbuf(__str, __mode | ios_base::in)
438 { this->init(&_M_stringbuf); }
439
440 /**
441 * @brief The destructor does nothing.
442 *
443 * The buffer is deallocated by the stringbuf object, not the
444 * formatting stream.
445 */
446 ~basic_istringstream()
447 { }
448
449#if __cplusplus >= 201103L
450 basic_istringstream(const basic_istringstream&) = delete;
451
452 basic_istringstream(basic_istringstream&& __rhs)
453 : __istream_type(std::move(__rhs)),
454 _M_stringbuf(std::move(__rhs._M_stringbuf))
455 { __istream_type::set_rdbuf(&_M_stringbuf); }
456
457 // 27.8.3.2 Assign and swap:
458
459 basic_istringstream&
460 operator=(const basic_istringstream&) = delete;
461
462 basic_istringstream&
463 operator=(basic_istringstream&& __rhs)
464 {
465 __istream_type::operator=(std::move(__rhs));
466 _M_stringbuf = std::move(__rhs._M_stringbuf);
467 return *this;
468 }
469
470 void
471 swap(basic_istringstream& __rhs)
472 {
473 __istream_type::swap(__rhs);
474 _M_stringbuf.swap(__rhs._M_stringbuf);
475 }
476#endif
477
478 // Members:
479 /**
480 * @brief Accessing the underlying buffer.
481 * @return The current basic_stringbuf buffer.
482 *
483 * This hides both signatures of std::basic_ios::rdbuf().
484 */
485 __stringbuf_type*
486 rdbuf() const
487 { return const_cast<__stringbuf_type*>(&_M_stringbuf); }
488
489 /**
490 * @brief Copying out the string buffer.
491 * @return @c rdbuf()->str()
492 */
493 __string_type
494 str() const
495 { return _M_stringbuf.str(); }
496
497 /**
498 * @brief Setting a new buffer.
499 * @param __s The string to use as a new sequence.
500 *
501 * Calls @c rdbuf()->str(s).
502 */
503 void
504 str(const __string_type& __s)
505 { _M_stringbuf.str(__s); }
506 };
507
508
509 // [27.7.3] Template class basic_ostringstream
510 /**
511 * @brief Controlling output for std::string.
512 * @ingroup io
513 *
514 * @tparam _CharT Type of character stream.
515 * @tparam _Traits Traits for character type, defaults to
516 * char_traits<_CharT>.
517 * @tparam _Alloc Allocator type, defaults to allocator<_CharT>.
518 *
519 * This class supports writing to objects of type std::basic_string,
520 * using the inherited functions from std::basic_ostream. To control
521 * the associated sequence, an instance of std::basic_stringbuf is used,
522 * which this page refers to as @c sb.
523 */
524 template <typename _CharT, typename _Traits, typename _Alloc>
525 class basic_ostringstream : public basic_ostream<_CharT, _Traits>
526 {
527 public:
528 // Types:
529 typedef _CharT char_type;
530 typedef _Traits traits_type;
531 // _GLIBCXX_RESOLVE_LIB_DEFECTS
532 // 251. basic_stringbuf missing allocator_type
533 typedef _Alloc allocator_type;
534 typedef typename traits_type::int_type int_type;
535 typedef typename traits_type::pos_type pos_type;
536 typedef typename traits_type::off_type off_type;
537
538 // Non-standard types:
539 typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
540 typedef basic_stringbuf<_CharT, _Traits, _Alloc> __stringbuf_type;
541 typedef basic_ostream<char_type, traits_type> __ostream_type;
542
543 private:
544 __stringbuf_type _M_stringbuf;
545
546 public:
547 // Constructors/destructor:
548 /**
549 * @brief Default constructor starts with an empty string buffer.
550 * @param __mode Whether the buffer can read, or write, or both.
551 *
552 * @c ios_base::out is automatically included in @a mode.
553 *
554 * Initializes @c sb using @c mode|out, and passes @c &sb to the base
555 * class initializer. Does not allocate any buffer.
556 *
557 * That's a lie. We initialize the base class with NULL, because the
558 * string class does its own memory management.
559 */
560 explicit
561 basic_ostringstream(ios_base::openmode __mode = ios_base::out)
562 : __ostream_type(), _M_stringbuf(__mode | ios_base::out)
563 { this->init(&_M_stringbuf); }
564
565 /**
566 * @brief Starts with an existing string buffer.
567 * @param __str A string to copy as a starting buffer.
568 * @param __mode Whether the buffer can read, or write, or both.
569 *
570 * @c ios_base::out is automatically included in @a mode.
571 *
572 * Initializes @c sb using @a str and @c mode|out, and passes @c &sb
573 * to the base class initializer.
574 *
575 * That's a lie. We initialize the base class with NULL, because the
576 * string class does its own memory management.
577 */
578 explicit
579 basic_ostringstream(const __string_type& __str,
580 ios_base::openmode __mode = ios_base::out)
581 : __ostream_type(), _M_stringbuf(__str, __mode | ios_base::out)
582 { this->init(&_M_stringbuf); }
583
584 /**
585 * @brief The destructor does nothing.
586 *
587 * The buffer is deallocated by the stringbuf object, not the
588 * formatting stream.
589 */
590 ~basic_ostringstream()
591 { }
592
593#if __cplusplus >= 201103L
594 basic_ostringstream(const basic_ostringstream&) = delete;
595
596 basic_ostringstream(basic_ostringstream&& __rhs)
597 : __ostream_type(std::move(__rhs)),
598 _M_stringbuf(std::move(__rhs._M_stringbuf))
599 { __ostream_type::set_rdbuf(&_M_stringbuf); }
600
601 // 27.8.3.2 Assign and swap:
602
603 basic_ostringstream&
604 operator=(const basic_ostringstream&) = delete;
605
606 basic_ostringstream&
607 operator=(basic_ostringstream&& __rhs)
608 {
609 __ostream_type::operator=(std::move(__rhs));
610 _M_stringbuf = std::move(__rhs._M_stringbuf);
611 return *this;
612 }
613
614 void
615 swap(basic_ostringstream& __rhs)
616 {
617 __ostream_type::swap(__rhs);
618 _M_stringbuf.swap(__rhs._M_stringbuf);
619 }
620#endif
621
622 // Members:
623 /**
624 * @brief Accessing the underlying buffer.
625 * @return The current basic_stringbuf buffer.
626 *
627 * This hides both signatures of std::basic_ios::rdbuf().
628 */
629 __stringbuf_type*
630 rdbuf() const
631 { return const_cast<__stringbuf_type*>(&_M_stringbuf); }
632
633 /**
634 * @brief Copying out the string buffer.
635 * @return @c rdbuf()->str()
636 */
637 __string_type
638 str() const
639 { return _M_stringbuf.str(); }
640
641 /**
642 * @brief Setting a new buffer.
643 * @param __s The string to use as a new sequence.
644 *
645 * Calls @c rdbuf()->str(s).
646 */
647 void
648 str(const __string_type& __s)
649 { _M_stringbuf.str(__s); }
650 };
651
652
653 // [27.7.4] Template class basic_stringstream
654 /**
655 * @brief Controlling input and output for std::string.
656 * @ingroup io
657 *
658 * @tparam _CharT Type of character stream.
659 * @tparam _Traits Traits for character type, defaults to
660 * char_traits<_CharT>.
661 * @tparam _Alloc Allocator type, defaults to allocator<_CharT>.
662 *
663 * This class supports reading from and writing to objects of type
664 * std::basic_string, using the inherited functions from
665 * std::basic_iostream. To control the associated sequence, an instance
666 * of std::basic_stringbuf is used, which this page refers to as @c sb.
667 */
668 template <typename _CharT, typename _Traits, typename _Alloc>
669 class basic_stringstream : public basic_iostream<_CharT, _Traits>
670 {
671 public:
672 // Types:
673 typedef _CharT char_type;
674 typedef _Traits traits_type;
675 // _GLIBCXX_RESOLVE_LIB_DEFECTS
676 // 251. basic_stringbuf missing allocator_type
677 typedef _Alloc allocator_type;
678 typedef typename traits_type::int_type int_type;
679 typedef typename traits_type::pos_type pos_type;
680 typedef typename traits_type::off_type off_type;
681
682 // Non-standard Types:
683 typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
684 typedef basic_stringbuf<_CharT, _Traits, _Alloc> __stringbuf_type;
685 typedef basic_iostream<char_type, traits_type> __iostream_type;
686
687 private:
688 __stringbuf_type _M_stringbuf;
689
690 public:
691 // Constructors/destructors
692 /**
693 * @brief Default constructor starts with an empty string buffer.
694 * @param __m Whether the buffer can read, or write, or both.
695 *
696 * Initializes @c sb using the mode from @c __m, and passes @c
697 * &sb to the base class initializer. Does not allocate any
698 * buffer.
699 *
700 * That's a lie. We initialize the base class with NULL, because the
701 * string class does its own memory management.
702 */
703 explicit
704 basic_stringstream(ios_base::openmode __m = ios_base::out | ios_base::in)
705 : __iostream_type(), _M_stringbuf(__m)
706 { this->init(&_M_stringbuf); }
707
708 /**
709 * @brief Starts with an existing string buffer.
710 * @param __str A string to copy as a starting buffer.
711 * @param __m Whether the buffer can read, or write, or both.
712 *
713 * Initializes @c sb using @a __str and @c __m, and passes @c &sb
714 * to the base class initializer.
715 *
716 * That's a lie. We initialize the base class with NULL, because the
717 * string class does its own memory management.
718 */
719 explicit
720 basic_stringstream(const __string_type& __str,
721 ios_base::openmode __m = ios_base::out | ios_base::in)
722 : __iostream_type(), _M_stringbuf(__str, __m)
723 { this->init(&_M_stringbuf); }
724
725 /**
726 * @brief The destructor does nothing.
727 *
728 * The buffer is deallocated by the stringbuf object, not the
729 * formatting stream.
730 */
731 ~basic_stringstream()
732 { }
733
734#if __cplusplus >= 201103L
735 basic_stringstream(const basic_stringstream&) = delete;
736
737 basic_stringstream(basic_stringstream&& __rhs)
738 : __iostream_type(std::move(__rhs)),
739 _M_stringbuf(std::move(__rhs._M_stringbuf))
740 { __iostream_type::set_rdbuf(&_M_stringbuf); }
741
742 // 27.8.3.2 Assign and swap:
743
744 basic_stringstream&
745 operator=(const basic_stringstream&) = delete;
746
747 basic_stringstream&
748 operator=(basic_stringstream&& __rhs)
749 {
750 __iostream_type::operator=(std::move(__rhs));
751 _M_stringbuf = std::move(__rhs._M_stringbuf);
752 return *this;
753 }
754
755 void
756 swap(basic_stringstream& __rhs)
757 {
758 __iostream_type::swap(__rhs);
759 _M_stringbuf.swap(__rhs._M_stringbuf);
760 }
761#endif
762
763 // Members:
764 /**
765 * @brief Accessing the underlying buffer.
766 * @return The current basic_stringbuf buffer.
767 *
768 * This hides both signatures of std::basic_ios::rdbuf().
769 */
770 __stringbuf_type*
771 rdbuf() const
772 { return const_cast<__stringbuf_type*>(&_M_stringbuf); }
773
774 /**
775 * @brief Copying out the string buffer.
776 * @return @c rdbuf()->str()
777 */
778 __string_type
779 str() const
780 { return _M_stringbuf.str(); }
781
782 /**
783 * @brief Setting a new buffer.
784 * @param __s The string to use as a new sequence.
785 *
786 * Calls @c rdbuf()->str(s).
787 */
788 void
789 str(const __string_type& __s)
790 { _M_stringbuf.str(__s); }
791 };
792
793#if __cplusplus >= 201103L
794 /// Swap specialization for stringbufs.
795 template <class _CharT, class _Traits, class _Allocator>
796 inline void
797 swap(basic_stringbuf<_CharT, _Traits, _Allocator>& __x,
798 basic_stringbuf<_CharT, _Traits, _Allocator>& __y)
799 { __x.swap(__y); }
800
801 /// Swap specialization for istringstreams.
802 template <class _CharT, class _Traits, class _Allocator>
803 inline void
804 swap(basic_istringstream<_CharT, _Traits, _Allocator>& __x,
805 basic_istringstream<_CharT, _Traits, _Allocator>& __y)
806 { __x.swap(__y); }
807
808 /// Swap specialization for ostringstreams.
809 template <class _CharT, class _Traits, class _Allocator>
810 inline void
811 swap(basic_ostringstream<_CharT, _Traits, _Allocator>& __x,
812 basic_ostringstream<_CharT, _Traits, _Allocator>& __y)
813 { __x.swap(__y); }
814
815 /// Swap specialization for stringstreams.
816 template <class _CharT, class _Traits, class _Allocator>
817 inline void
818 swap(basic_stringstream<_CharT, _Traits, _Allocator>& __x,
819 basic_stringstream<_CharT, _Traits, _Allocator>& __y)
820 { __x.swap(__y); }
821#endif
822
823_GLIBCXX_END_NAMESPACE_CXX11
824_GLIBCXX_END_NAMESPACE_VERSION
825} // namespace
826
827#include <bits/sstream.tcc>
828
829#endif /* _GLIBCXX_SSTREAM */
830