libstdc++

basic_string.tcc
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1 // Components for manipulating sequences of characters -*- C++ -*-
2
3 // Copyright (C) 1997-2013 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/basic_string.tcc
26 * This is an internal header file, included by other library headers.
27 * Do not attempt to use it directly. @headername{string}
28 */
29
30 //
31 // ISO C++ 14882: 21 Strings library
32 //
33
34 // Written by Jason Merrill based upon the specification by Takanori Adachi
35 // in ANSI X3J16/94-0013R2. Rewritten by Nathan Myers to ISO-14882.
36
37 #ifndef _BASIC_STRING_TCC
38 #define _BASIC_STRING_TCC 1
39
40 #pragma GCC system_header
41
42 #include <bits/cxxabi_forced.h>
43
44 namespace std _GLIBCXX_VISIBILITY(default)
45 {
46 _GLIBCXX_BEGIN_NAMESPACE_VERSION
47
48 template<typename _CharT, typename _Traits, typename _Alloc>
49 const typename basic_string<_CharT, _Traits, _Alloc>::size_type
50 basic_string<_CharT, _Traits, _Alloc>::
51 _Rep::_S_max_size = (((npos - sizeof(_Rep_base))/sizeof(_CharT)) - 1) / 4;
52
53 template<typename _CharT, typename _Traits, typename _Alloc>
54 const _CharT
55 basic_string<_CharT, _Traits, _Alloc>::
56 _Rep::_S_terminal = _CharT();
57
58 template<typename _CharT, typename _Traits, typename _Alloc>
59 const typename basic_string<_CharT, _Traits, _Alloc>::size_type
60 basic_string<_CharT, _Traits, _Alloc>::npos;
61
62 // Linker sets _S_empty_rep_storage to all 0s (one reference, empty string)
63 // at static init time (before static ctors are run).
64 template<typename _CharT, typename _Traits, typename _Alloc>
65 typename basic_string<_CharT, _Traits, _Alloc>::size_type
66 basic_string<_CharT, _Traits, _Alloc>::_Rep::_S_empty_rep_storage[
67 (sizeof(_Rep_base) + sizeof(_CharT) + sizeof(size_type) - 1) /
68 sizeof(size_type)];
69
70 // NB: This is the special case for Input Iterators, used in
71 // istreambuf_iterators, etc.
72 // Input Iterators have a cost structure very different from
73 // pointers, calling for a different coding style.
74 template<typename _CharT, typename _Traits, typename _Alloc>
75 template<typename _InIterator>
76 _CharT*
77 basic_string<_CharT, _Traits, _Alloc>::
78 _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
79 input_iterator_tag)
80 {
81 #if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
82 if (__beg == __end && __a == _Alloc())
83 return _S_empty_rep()._M_refdata();
84 #endif
85 // Avoid reallocation for common case.
86 _CharT __buf[128];
87 size_type __len = 0;
88 while (__beg != __end && __len < sizeof(__buf) / sizeof(_CharT))
89 {
90 __buf[__len++] = *__beg;
91 ++__beg;
92 }
93 _Rep* __r = _Rep::_S_create(__len, size_type(0), __a);
94 _M_copy(__r->_M_refdata(), __buf, __len);
95 __try
96 {
97 while (__beg != __end)
98 {
99 if (__len == __r->_M_capacity)
100 {
101 // Allocate more space.
102 _Rep* __another = _Rep::_S_create(__len + 1, __len, __a);
103 _M_copy(__another->_M_refdata(), __r->_M_refdata(), __len);
104 __r->_M_destroy(__a);
105 __r = __another;
106 }
107 __r->_M_refdata()[__len++] = *__beg;
108 ++__beg;
109 }
110 }
111 __catch(...)
112 {
113 __r->_M_destroy(__a);
114 __throw_exception_again;
115 }
116 __r->_M_set_length_and_sharable(__len);
117 return __r->_M_refdata();
118 }
119
120 template<typename _CharT, typename _Traits, typename _Alloc>
121 template <typename _InIterator>
122 _CharT*
123 basic_string<_CharT, _Traits, _Alloc>::
124 _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
125 forward_iterator_tag)
126 {
127 #if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
128 if (__beg == __end && __a == _Alloc())
129 return _S_empty_rep()._M_refdata();
130 #endif
131 // NB: Not required, but considered best practice.
132 if (__gnu_cxx::__is_null_pointer(__beg) && __beg != __end)
133 __throw_logic_error(__N("basic_string::_S_construct null not valid"));
134
135 const size_type __dnew = static_cast<size_type>(std::distance(__beg,
136 __end));
137 // Check for out_of_range and length_error exceptions.
138 _Rep* __r = _Rep::_S_create(__dnew, size_type(0), __a);
139 __try
140 { _S_copy_chars(__r->_M_refdata(), __beg, __end); }
141 __catch(...)
142 {
143 __r->_M_destroy(__a);
144 __throw_exception_again;
145 }
146 __r->_M_set_length_and_sharable(__dnew);
147 return __r->_M_refdata();
148 }
149
150 template<typename _CharT, typename _Traits, typename _Alloc>
151 _CharT*
152 basic_string<_CharT, _Traits, _Alloc>::
153 _S_construct(size_type __n, _CharT __c, const _Alloc& __a)
154 {
155 #if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
156 if (__n == 0 && __a == _Alloc())
157 return _S_empty_rep()._M_refdata();
158 #endif
159 // Check for out_of_range and length_error exceptions.
160 _Rep* __r = _Rep::_S_create(__n, size_type(0), __a);
161 if (__n)
162 _M_assign(__r->_M_refdata(), __n, __c);
163
164 __r->_M_set_length_and_sharable(__n);
165 return __r->_M_refdata();
166 }
167
168 template<typename _CharT, typename _Traits, typename _Alloc>
169 basic_string<_CharT, _Traits, _Alloc>::
170 basic_string(const basic_string& __str)
171 : _M_dataplus(__str._M_rep()->_M_grab(_Alloc(__str.get_allocator()),
172 __str.get_allocator()),
173 __str.get_allocator())
174 { }
175
176 template<typename _CharT, typename _Traits, typename _Alloc>
177 basic_string<_CharT, _Traits, _Alloc>::
178 basic_string(const _Alloc& __a)
179 : _M_dataplus(_S_construct(size_type(), _CharT(), __a), __a)
180 { }
181
182 template<typename _CharT, typename _Traits, typename _Alloc>
183 basic_string<_CharT, _Traits, _Alloc>::
184 basic_string(const basic_string& __str, size_type __pos, size_type __n)
185 : _M_dataplus(_S_construct(__str._M_data()
186 + __str._M_check(__pos,
187 "basic_string::basic_string"),
188 __str._M_data() + __str._M_limit(__pos, __n)
189 + __pos, _Alloc()), _Alloc())
190 { }
191
192 template<typename _CharT, typename _Traits, typename _Alloc>
193 basic_string<_CharT, _Traits, _Alloc>::
194 basic_string(const basic_string& __str, size_type __pos,
195 size_type __n, const _Alloc& __a)
196 : _M_dataplus(_S_construct(__str._M_data()
197 + __str._M_check(__pos,
198 "basic_string::basic_string"),
199 __str._M_data() + __str._M_limit(__pos, __n)
200 + __pos, __a), __a)
201 { }
202
203 // TBD: DPG annotate
204 template<typename _CharT, typename _Traits, typename _Alloc>
205 basic_string<_CharT, _Traits, _Alloc>::
206 basic_string(const _CharT* __s, size_type __n, const _Alloc& __a)
207 : _M_dataplus(_S_construct(__s, __s + __n, __a), __a)
208 { }
209
210 // TBD: DPG annotate
211 template<typename _CharT, typename _Traits, typename _Alloc>
212 basic_string<_CharT, _Traits, _Alloc>::
213 basic_string(const _CharT* __s, const _Alloc& __a)
214 : _M_dataplus(_S_construct(__s, __s ? __s + traits_type::length(__s) :
215 __s + npos, __a), __a)
216 { }
217
218 template<typename _CharT, typename _Traits, typename _Alloc>
219 basic_string<_CharT, _Traits, _Alloc>::
220 basic_string(size_type __n, _CharT __c, const _Alloc& __a)
221 : _M_dataplus(_S_construct(__n, __c, __a), __a)
222 { }
223
224 // TBD: DPG annotate
225 template<typename _CharT, typename _Traits, typename _Alloc>
226 template<typename _InputIterator>
227 basic_string<_CharT, _Traits, _Alloc>::
228 basic_string(_InputIterator __beg, _InputIterator __end, const _Alloc& __a)
229 : _M_dataplus(_S_construct(__beg, __end, __a), __a)
230 { }
231
232 #if __cplusplus >= 201103L
233 template<typename _CharT, typename _Traits, typename _Alloc>
234 basic_string<_CharT, _Traits, _Alloc>::
235 basic_string(initializer_list<_CharT> __l, const _Alloc& __a)
236 : _M_dataplus(_S_construct(__l.begin(), __l.end(), __a), __a)
237 { }
238 #endif
239
240 template<typename _CharT, typename _Traits, typename _Alloc>
241 basic_string<_CharT, _Traits, _Alloc>&
242 basic_string<_CharT, _Traits, _Alloc>::
243 assign(const basic_string& __str)
244 {
245 if (_M_rep() != __str._M_rep())
246 {
247 // XXX MT
248 const allocator_type __a = this->get_allocator();
249 _CharT* __tmp = __str._M_rep()->_M_grab(__a, __str.get_allocator());
250 _M_rep()->_M_dispose(__a);
251 _M_data(__tmp);
252 }
253 return *this;
254 }
255
256 template<typename _CharT, typename _Traits, typename _Alloc>
257 basic_string<_CharT, _Traits, _Alloc>&
258 basic_string<_CharT, _Traits, _Alloc>::
259 assign(const _CharT* __s, size_type __n)
260 {
261 __glibcxx_requires_string_len(__s, __n);
262 _M_check_length(this->size(), __n, "basic_string::assign");
263 if (_M_disjunct(__s) || _M_rep()->_M_is_shared())
264 return _M_replace_safe(size_type(0), this->size(), __s, __n);
265 else
266 {
267 // Work in-place.
268 const size_type __pos = __s - _M_data();
269 if (__pos >= __n)
270 _M_copy(_M_data(), __s, __n);
271 else if (__pos)
272 _M_move(_M_data(), __s, __n);
273 _M_rep()->_M_set_length_and_sharable(__n);
274 return *this;
275 }
276 }
277
278 template<typename _CharT, typename _Traits, typename _Alloc>
279 basic_string<_CharT, _Traits, _Alloc>&
280 basic_string<_CharT, _Traits, _Alloc>::
281 append(size_type __n, _CharT __c)
282 {
283 if (__n)
284 {
285 _M_check_length(size_type(0), __n, "basic_string::append");
286 const size_type __len = __n + this->size();
287 if (__len > this->capacity() || _M_rep()->_M_is_shared())
288 this->reserve(__len);
289 _M_assign(_M_data() + this->size(), __n, __c);
290 _M_rep()->_M_set_length_and_sharable(__len);
291 }
292 return *this;
293 }
294
295 template<typename _CharT, typename _Traits, typename _Alloc>
296 basic_string<_CharT, _Traits, _Alloc>&
297 basic_string<_CharT, _Traits, _Alloc>::
298 append(const _CharT* __s, size_type __n)
299 {
300 __glibcxx_requires_string_len(__s, __n);
301 if (__n)
302 {
303 _M_check_length(size_type(0), __n, "basic_string::append");
304 const size_type __len = __n + this->size();
305 if (__len > this->capacity() || _M_rep()->_M_is_shared())
306 {
307 if (_M_disjunct(__s))
308 this->reserve(__len);
309 else
310 {
311 const size_type __off = __s - _M_data();
312 this->reserve(__len);
313 __s = _M_data() + __off;
314 }
315 }
316 _M_copy(_M_data() + this->size(), __s, __n);
317 _M_rep()->_M_set_length_and_sharable(__len);
318 }
319 return *this;
320 }
321
322 template<typename _CharT, typename _Traits, typename _Alloc>
323 basic_string<_CharT, _Traits, _Alloc>&
324 basic_string<_CharT, _Traits, _Alloc>::
325 append(const basic_string& __str)
326 {
327 const size_type __size = __str.size();
328 if (__size)
329 {
330 const size_type __len = __size + this->size();
331 if (__len > this->capacity() || _M_rep()->_M_is_shared())
332 this->reserve(__len);
333 _M_copy(_M_data() + this->size(), __str._M_data(), __size);
334 _M_rep()->_M_set_length_and_sharable(__len);
335 }
336 return *this;
337 }
338
339 template<typename _CharT, typename _Traits, typename _Alloc>
340 basic_string<_CharT, _Traits, _Alloc>&
341 basic_string<_CharT, _Traits, _Alloc>::
342 append(const basic_string& __str, size_type __pos, size_type __n)
343 {
344 __str._M_check(__pos, "basic_string::append");
345 __n = __str._M_limit(__pos, __n);
346 if (__n)
347 {
348 const size_type __len = __n + this->size();
349 if (__len > this->capacity() || _M_rep()->_M_is_shared())
350 this->reserve(__len);
351 _M_copy(_M_data() + this->size(), __str._M_data() + __pos, __n);
352 _M_rep()->_M_set_length_and_sharable(__len);
353 }
354 return *this;
355 }
356
357 template<typename _CharT, typename _Traits, typename _Alloc>
358 basic_string<_CharT, _Traits, _Alloc>&
359 basic_string<_CharT, _Traits, _Alloc>::
360 insert(size_type __pos, const _CharT* __s, size_type __n)
361 {
362 __glibcxx_requires_string_len(__s, __n);
363 _M_check(__pos, "basic_string::insert");
364 _M_check_length(size_type(0), __n, "basic_string::insert");
365 if (_M_disjunct(__s) || _M_rep()->_M_is_shared())
366 return _M_replace_safe(__pos, size_type(0), __s, __n);
367 else
368 {
369 // Work in-place.
370 const size_type __off = __s - _M_data();
371 _M_mutate(__pos, 0, __n);
372 __s = _M_data() + __off;
373 _CharT* __p = _M_data() + __pos;
374 if (__s + __n <= __p)
375 _M_copy(__p, __s, __n);
376 else if (__s >= __p)
377 _M_copy(__p, __s + __n, __n);
378 else
379 {
380 const size_type __nleft = __p - __s;
381 _M_copy(__p, __s, __nleft);
382 _M_copy(__p + __nleft, __p + __n, __n - __nleft);
383 }
384 return *this;
385 }
386 }
387
388 template<typename _CharT, typename _Traits, typename _Alloc>
389 typename basic_string<_CharT, _Traits, _Alloc>::iterator
390 basic_string<_CharT, _Traits, _Alloc>::
391 erase(iterator __first, iterator __last)
392 {
393 _GLIBCXX_DEBUG_PEDASSERT(__first >= _M_ibegin() && __first <= __last
394 && __last <= _M_iend());
395
396 // NB: This isn't just an optimization (bail out early when
397 // there is nothing to do, really), it's also a correctness
398 // issue vs MT, see libstdc++/40518.
399 const size_type __size = __last - __first;
400 if (__size)
401 {
402 const size_type __pos = __first - _M_ibegin();
403 _M_mutate(__pos, __size, size_type(0));
404 _M_rep()->_M_set_leaked();
405 return iterator(_M_data() + __pos);
406 }
407 else
408 return __first;
409 }
410
411 template<typename _CharT, typename _Traits, typename _Alloc>
412 basic_string<_CharT, _Traits, _Alloc>&
413 basic_string<_CharT, _Traits, _Alloc>::
414 replace(size_type __pos, size_type __n1, const _CharT* __s,
415 size_type __n2)
416 {
417 __glibcxx_requires_string_len(__s, __n2);
418 _M_check(__pos, "basic_string::replace");
419 __n1 = _M_limit(__pos, __n1);
420 _M_check_length(__n1, __n2, "basic_string::replace");
421 bool __left;
422 if (_M_disjunct(__s) || _M_rep()->_M_is_shared())
423 return _M_replace_safe(__pos, __n1, __s, __n2);
424 else if ((__left = __s + __n2 <= _M_data() + __pos)
425 || _M_data() + __pos + __n1 <= __s)
426 {
427 // Work in-place: non-overlapping case.
428 size_type __off = __s - _M_data();
429 __left ? __off : (__off += __n2 - __n1);
430 _M_mutate(__pos, __n1, __n2);
431 _M_copy(_M_data() + __pos, _M_data() + __off, __n2);
432 return *this;
433 }
434 else
435 {
436 // Todo: overlapping case.
437 const basic_string __tmp(__s, __n2);
438 return _M_replace_safe(__pos, __n1, __tmp._M_data(), __n2);
439 }
440 }
441
442 template<typename _CharT, typename _Traits, typename _Alloc>
443 void
444 basic_string<_CharT, _Traits, _Alloc>::_Rep::
445 _M_destroy(const _Alloc& __a) throw ()
446 {
447 const size_type __size = sizeof(_Rep_base) +
448 (this->_M_capacity + 1) * sizeof(_CharT);
449 _Raw_bytes_alloc(__a).deallocate(reinterpret_cast<char*>(this), __size);
450 }
451
452 template<typename _CharT, typename _Traits, typename _Alloc>
453 void
454 basic_string<_CharT, _Traits, _Alloc>::
455 _M_leak_hard()
456 {
457 #if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
458 if (_M_rep() == &_S_empty_rep())
459 return;
460 #endif
461 if (_M_rep()->_M_is_shared())
462 _M_mutate(0, 0, 0);
463 _M_rep()->_M_set_leaked();
464 }
465
466 template<typename _CharT, typename _Traits, typename _Alloc>
467 void
468 basic_string<_CharT, _Traits, _Alloc>::
469 _M_mutate(size_type __pos, size_type __len1, size_type __len2)
470 {
471 const size_type __old_size = this->size();
472 const size_type __new_size = __old_size + __len2 - __len1;
473 const size_type __how_much = __old_size - __pos - __len1;
474
475 if (__new_size > this->capacity() || _M_rep()->_M_is_shared())
476 {
477 // Must reallocate.
478 const allocator_type __a = get_allocator();
479 _Rep* __r = _Rep::_S_create(__new_size, this->capacity(), __a);
480
481 if (__pos)
482 _M_copy(__r->_M_refdata(), _M_data(), __pos);
483 if (__how_much)
484 _M_copy(__r->_M_refdata() + __pos + __len2,
485 _M_data() + __pos + __len1, __how_much);
486
487 _M_rep()->_M_dispose(__a);
488 _M_data(__r->_M_refdata());
489 }
490 else if (__how_much && __len1 != __len2)
491 {
492 // Work in-place.
493 _M_move(_M_data() + __pos + __len2,
494 _M_data() + __pos + __len1, __how_much);
495 }
496 _M_rep()->_M_set_length_and_sharable(__new_size);
497 }
498
499 template<typename _CharT, typename _Traits, typename _Alloc>
500 void
501 basic_string<_CharT, _Traits, _Alloc>::
502 reserve(size_type __res)
503 {
504 if (__res != this->capacity() || _M_rep()->_M_is_shared())
505 {
506 // Make sure we don't shrink below the current size
507 if (__res < this->size())
508 __res = this->size();
509 const allocator_type __a = get_allocator();
510 _CharT* __tmp = _M_rep()->_M_clone(__a, __res - this->size());
511 _M_rep()->_M_dispose(__a);
512 _M_data(__tmp);
513 }
514 }
515
516 template<typename _CharT, typename _Traits, typename _Alloc>
517 void
518 basic_string<_CharT, _Traits, _Alloc>::
519 swap(basic_string& __s)
520 {
521 if (_M_rep()->_M_is_leaked())
522 _M_rep()->_M_set_sharable();
523 if (__s._M_rep()->_M_is_leaked())
524 __s._M_rep()->_M_set_sharable();
525 if (this->get_allocator() == __s.get_allocator())
526 {
527 _CharT* __tmp = _M_data();
528 _M_data(__s._M_data());
529 __s._M_data(__tmp);
530 }
531 // The code below can usually be optimized away.
532 else
533 {
534 const basic_string __tmp1(_M_ibegin(), _M_iend(),
535 __s.get_allocator());
536 const basic_string __tmp2(__s._M_ibegin(), __s._M_iend(),
537 this->get_allocator());
538 *this = __tmp2;
539 __s = __tmp1;
540 }
541 }
542
543 template<typename _CharT, typename _Traits, typename _Alloc>
544 typename basic_string<_CharT, _Traits, _Alloc>::_Rep*
545 basic_string<_CharT, _Traits, _Alloc>::_Rep::
546 _S_create(size_type __capacity, size_type __old_capacity,
547 const _Alloc& __alloc)
548 {
549 // _GLIBCXX_RESOLVE_LIB_DEFECTS
550 // 83. String::npos vs. string::max_size()
551 if (__capacity > _S_max_size)
552 __throw_length_error(__N("basic_string::_S_create"));
553
554 // The standard places no restriction on allocating more memory
555 // than is strictly needed within this layer at the moment or as
556 // requested by an explicit application call to reserve().
557
558 // Many malloc implementations perform quite poorly when an
559 // application attempts to allocate memory in a stepwise fashion
560 // growing each allocation size by only 1 char. Additionally,
561 // it makes little sense to allocate less linear memory than the
562 // natural blocking size of the malloc implementation.
563 // Unfortunately, we would need a somewhat low-level calculation
564 // with tuned parameters to get this perfect for any particular
565 // malloc implementation. Fortunately, generalizations about
566 // common features seen among implementations seems to suffice.
567
568 // __pagesize need not match the actual VM page size for good
569 // results in practice, thus we pick a common value on the low
570 // side. __malloc_header_size is an estimate of the amount of
571 // overhead per memory allocation (in practice seen N * sizeof
572 // (void*) where N is 0, 2 or 4). According to folklore,
573 // picking this value on the high side is better than
574 // low-balling it (especially when this algorithm is used with
575 // malloc implementations that allocate memory blocks rounded up
576 // to a size which is a power of 2).
577 const size_type __pagesize = 4096;
578 const size_type __malloc_header_size = 4 * sizeof(void*);
579
580 // The below implements an exponential growth policy, necessary to
581 // meet amortized linear time requirements of the library: see
582 // http://gcc.gnu.org/ml/libstdc++/2001-07/msg00085.html.
583 // It's active for allocations requiring an amount of memory above
584 // system pagesize. This is consistent with the requirements of the
585 // standard: http://gcc.gnu.org/ml/libstdc++/2001-07/msg00130.html
586 if (__capacity > __old_capacity && __capacity < 2 * __old_capacity)
587 __capacity = 2 * __old_capacity;
588
589 // NB: Need an array of char_type[__capacity], plus a terminating
590 // null char_type() element, plus enough for the _Rep data structure.
591 // Whew. Seemingly so needy, yet so elemental.
592 size_type __size = (__capacity + 1) * sizeof(_CharT) + sizeof(_Rep);
593
594 const size_type __adj_size = __size + __malloc_header_size;
595 if (__adj_size > __pagesize && __capacity > __old_capacity)
596 {
597 const size_type __extra = __pagesize - __adj_size % __pagesize;
598 __capacity += __extra / sizeof(_CharT);
599 // Never allocate a string bigger than _S_max_size.
600 if (__capacity > _S_max_size)
601 __capacity = _S_max_size;
602 __size = (__capacity + 1) * sizeof(_CharT) + sizeof(_Rep);
603 }
604
605 // NB: Might throw, but no worries about a leak, mate: _Rep()
606 // does not throw.
607 void* __place = _Raw_bytes_alloc(__alloc).allocate(__size);
608 _Rep *__p = new (__place) _Rep;
609 __p->_M_capacity = __capacity;
610 // ABI compatibility - 3.4.x set in _S_create both
611 // _M_refcount and _M_length. All callers of _S_create
612 // in basic_string.tcc then set just _M_length.
613 // In 4.0.x and later both _M_refcount and _M_length
614 // are initialized in the callers, unfortunately we can
615 // have 3.4.x compiled code with _S_create callers inlined
616 // calling 4.0.x+ _S_create.
617 __p->_M_set_sharable();
618 return __p;
619 }
620
621 template<typename _CharT, typename _Traits, typename _Alloc>
622 _CharT*
623 basic_string<_CharT, _Traits, _Alloc>::_Rep::
624 _M_clone(const _Alloc& __alloc, size_type __res)
625 {
626 // Requested capacity of the clone.
627 const size_type __requested_cap = this->_M_length + __res;
628 _Rep* __r = _Rep::_S_create(__requested_cap, this->_M_capacity,
629 __alloc);
630 if (this->_M_length)
631 _M_copy(__r->_M_refdata(), _M_refdata(), this->_M_length);
632
633 __r->_M_set_length_and_sharable(this->_M_length);
634 return __r->_M_refdata();
635 }
636
637 template<typename _CharT, typename _Traits, typename _Alloc>
638 void
639 basic_string<_CharT, _Traits, _Alloc>::
640 resize(size_type __n, _CharT __c)
641 {
642 const size_type __size = this->size();
643 _M_check_length(__size, __n, "basic_string::resize");
644 if (__size < __n)
645 this->append(__n - __size, __c);
646 else if (__n < __size)
647 this->erase(__n);
648 // else nothing (in particular, avoid calling _M_mutate() unnecessarily.)
649 }
650
651 template<typename _CharT, typename _Traits, typename _Alloc>
652 template<typename _InputIterator>
653 basic_string<_CharT, _Traits, _Alloc>&
654 basic_string<_CharT, _Traits, _Alloc>::
655 _M_replace_dispatch(iterator __i1, iterator __i2, _InputIterator __k1,
656 _InputIterator __k2, __false_type)
657 {
658 const basic_string __s(__k1, __k2);
659 const size_type __n1 = __i2 - __i1;
660 _M_check_length(__n1, __s.size(), "basic_string::_M_replace_dispatch");
661 return _M_replace_safe(__i1 - _M_ibegin(), __n1, __s._M_data(),
662 __s.size());
663 }
664
665 template<typename _CharT, typename _Traits, typename _Alloc>
666 basic_string<_CharT, _Traits, _Alloc>&
667 basic_string<_CharT, _Traits, _Alloc>::
668 _M_replace_aux(size_type __pos1, size_type __n1, size_type __n2,
669 _CharT __c)
670 {
671 _M_check_length(__n1, __n2, "basic_string::_M_replace_aux");
672 _M_mutate(__pos1, __n1, __n2);
673 if (__n2)
674 _M_assign(_M_data() + __pos1, __n2, __c);
675 return *this;
676 }
677
678 template<typename _CharT, typename _Traits, typename _Alloc>
679 basic_string<_CharT, _Traits, _Alloc>&
680 basic_string<_CharT, _Traits, _Alloc>::
681 _M_replace_safe(size_type __pos1, size_type __n1, const _CharT* __s,
682 size_type __n2)
683 {
684 _M_mutate(__pos1, __n1, __n2);
685 if (__n2)
686 _M_copy(_M_data() + __pos1, __s, __n2);
687 return *this;
688 }
689
690 template<typename _CharT, typename _Traits, typename _Alloc>
691 basic_string<_CharT, _Traits, _Alloc>
692 operator+(const _CharT* __lhs,
693 const basic_string<_CharT, _Traits, _Alloc>& __rhs)
694 {
695 __glibcxx_requires_string(__lhs);
696 typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
697 typedef typename __string_type::size_type __size_type;
698 const __size_type __len = _Traits::length(__lhs);
699 __string_type __str;
700 __str.reserve(__len + __rhs.size());
701 __str.append(__lhs, __len);
702 __str.append(__rhs);
703 return __str;
704 }
705
706 template<typename _CharT, typename _Traits, typename _Alloc>
707 basic_string<_CharT, _Traits, _Alloc>
708 operator+(_CharT __lhs, const basic_string<_CharT, _Traits, _Alloc>& __rhs)
709 {
710 typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
711 typedef typename __string_type::size_type __size_type;
712 __string_type __str;
713 const __size_type __len = __rhs.size();
714 __str.reserve(__len + 1);
715 __str.append(__size_type(1), __lhs);
716 __str.append(__rhs);
717 return __str;
718 }
719
720 template<typename _CharT, typename _Traits, typename _Alloc>
721 typename basic_string<_CharT, _Traits, _Alloc>::size_type
722 basic_string<_CharT, _Traits, _Alloc>::
723 copy(_CharT* __s, size_type __n, size_type __pos) const
724 {
725 _M_check(__pos, "basic_string::copy");
726 __n = _M_limit(__pos, __n);
727 __glibcxx_requires_string_len(__s, __n);
728 if (__n)
729 _M_copy(__s, _M_data() + __pos, __n);
730 // 21.3.5.7 par 3: do not append null. (good.)
731 return __n;
732 }
733
734 template<typename _CharT, typename _Traits, typename _Alloc>
735 typename basic_string<_CharT, _Traits, _Alloc>::size_type
736 basic_string<_CharT, _Traits, _Alloc>::
737 find(const _CharT* __s, size_type __pos, size_type __n) const
738 {
739 __glibcxx_requires_string_len(__s, __n);
740 const size_type __size = this->size();
741 const _CharT* __data = _M_data();
742
743 if (__n == 0)
744 return __pos <= __size ? __pos : npos;
745
746 if (__n <= __size)
747 {
748 for (; __pos <= __size - __n; ++__pos)
749 if (traits_type::eq(__data[__pos], __s[0])
750 && traits_type::compare(__data + __pos + 1,
751 __s + 1, __n - 1) == 0)
752 return __pos;
753 }
754 return npos;
755 }
756
757 template<typename _CharT, typename _Traits, typename _Alloc>
758 typename basic_string<_CharT, _Traits, _Alloc>::size_type
759 basic_string<_CharT, _Traits, _Alloc>::
760 find(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
761 {
762 size_type __ret = npos;
763 const size_type __size = this->size();
764 if (__pos < __size)
765 {
766 const _CharT* __data = _M_data();
767 const size_type __n = __size - __pos;
768 const _CharT* __p = traits_type::find(__data + __pos, __n, __c);
769 if (__p)
770 __ret = __p - __data;
771 }
772 return __ret;
773 }
774
775 template<typename _CharT, typename _Traits, typename _Alloc>
776 typename basic_string<_CharT, _Traits, _Alloc>::size_type
777 basic_string<_CharT, _Traits, _Alloc>::
778 rfind(const _CharT* __s, size_type __pos, size_type __n) const
779 {
780 __glibcxx_requires_string_len(__s, __n);
781 const size_type __size = this->size();
782 if (__n <= __size)
783 {
784 __pos = std::min(size_type(__size - __n), __pos);
785 const _CharT* __data = _M_data();
786 do
787 {
788 if (traits_type::compare(__data + __pos, __s, __n) == 0)
789 return __pos;
790 }
791 while (__pos-- > 0);
792 }
793 return npos;
794 }
795
796 template<typename _CharT, typename _Traits, typename _Alloc>
797 typename basic_string<_CharT, _Traits, _Alloc>::size_type
798 basic_string<_CharT, _Traits, _Alloc>::
799 rfind(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
800 {
801 size_type __size = this->size();
802 if (__size)
803 {
804 if (--__size > __pos)
805 __size = __pos;
806 for (++__size; __size-- > 0; )
807 if (traits_type::eq(_M_data()[__size], __c))
808 return __size;
809 }
810 return npos;
811 }
812
813 template<typename _CharT, typename _Traits, typename _Alloc>
814 typename basic_string<_CharT, _Traits, _Alloc>::size_type
815 basic_string<_CharT, _Traits, _Alloc>::
816 find_first_of(const _CharT* __s, size_type __pos, size_type __n) const
817 {
818 __glibcxx_requires_string_len(__s, __n);
819 for (; __n && __pos < this->size(); ++__pos)
820 {
821 const _CharT* __p = traits_type::find(__s, __n, _M_data()[__pos]);
822 if (__p)
823 return __pos;
824 }
825 return npos;
826 }
827
828 template<typename _CharT, typename _Traits, typename _Alloc>
829 typename basic_string<_CharT, _Traits, _Alloc>::size_type
830 basic_string<_CharT, _Traits, _Alloc>::
831 find_last_of(const _CharT* __s, size_type __pos, size_type __n) const
832 {
833 __glibcxx_requires_string_len(__s, __n);
834 size_type __size = this->size();
835 if (__size && __n)
836 {
837 if (--__size > __pos)
838 __size = __pos;
839 do
840 {
841 if (traits_type::find(__s, __n, _M_data()[__size]))
842 return __size;
843 }
844 while (__size-- != 0);
845 }
846 return npos;
847 }
848
849 template<typename _CharT, typename _Traits, typename _Alloc>
850 typename basic_string<_CharT, _Traits, _Alloc>::size_type
851 basic_string<_CharT, _Traits, _Alloc>::
852 find_first_not_of(const _CharT* __s, size_type __pos, size_type __n) const
853 {
854 __glibcxx_requires_string_len(__s, __n);
855 for (; __pos < this->size(); ++__pos)
856 if (!traits_type::find(__s, __n, _M_data()[__pos]))
857 return __pos;
858 return npos;
859 }
860
861 template<typename _CharT, typename _Traits, typename _Alloc>
862 typename basic_string<_CharT, _Traits, _Alloc>::size_type
863 basic_string<_CharT, _Traits, _Alloc>::
864 find_first_not_of(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
865 {
866 for (; __pos < this->size(); ++__pos)
867 if (!traits_type::eq(_M_data()[__pos], __c))
868 return __pos;
869 return npos;
870 }
871
872 template<typename _CharT, typename _Traits, typename _Alloc>
873 typename basic_string<_CharT, _Traits, _Alloc>::size_type
874 basic_string<_CharT, _Traits, _Alloc>::
875 find_last_not_of(const _CharT* __s, size_type __pos, size_type __n) const
876 {
877 __glibcxx_requires_string_len(__s, __n);
878 size_type __size = this->size();
879 if (__size)
880 {
881 if (--__size > __pos)
882 __size = __pos;
883 do
884 {
885 if (!traits_type::find(__s, __n, _M_data()[__size]))
886 return __size;
887 }
888 while (__size--);
889 }
890 return npos;
891 }
892
893 template<typename _CharT, typename _Traits, typename _Alloc>
894 typename basic_string<_CharT, _Traits, _Alloc>::size_type
895 basic_string<_CharT, _Traits, _Alloc>::
896 find_last_not_of(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
897 {
898 size_type __size = this->size();
899 if (__size)
900 {
901 if (--__size > __pos)
902 __size = __pos;
903 do
904 {
905 if (!traits_type::eq(_M_data()[__size], __c))
906 return __size;
907 }
908 while (__size--);
909 }
910 return npos;
911 }
912
913 template<typename _CharT, typename _Traits, typename _Alloc>
914 int
915 basic_string<_CharT, _Traits, _Alloc>::
916 compare(size_type __pos, size_type __n, const basic_string& __str) const
917 {
918 _M_check(__pos, "basic_string::compare");
919 __n = _M_limit(__pos, __n);
920 const size_type __osize = __str.size();
921 const size_type __len = std::min(__n, __osize);
922 int __r = traits_type::compare(_M_data() + __pos, __str.data(), __len);
923 if (!__r)
924 __r = _S_compare(__n, __osize);
925 return __r;
926 }
927
928 template<typename _CharT, typename _Traits, typename _Alloc>
929 int
930 basic_string<_CharT, _Traits, _Alloc>::
931 compare(size_type __pos1, size_type __n1, const basic_string& __str,
932 size_type __pos2, size_type __n2) const
933 {
934 _M_check(__pos1, "basic_string::compare");
935 __str._M_check(__pos2, "basic_string::compare");
936 __n1 = _M_limit(__pos1, __n1);
937 __n2 = __str._M_limit(__pos2, __n2);
938 const size_type __len = std::min(__n1, __n2);
939 int __r = traits_type::compare(_M_data() + __pos1,
940 __str.data() + __pos2, __len);
941 if (!__r)
942 __r = _S_compare(__n1, __n2);
943 return __r;
944 }
945
946 template<typename _CharT, typename _Traits, typename _Alloc>
947 int
948 basic_string<_CharT, _Traits, _Alloc>::
949 compare(const _CharT* __s) const
950 {
951 __glibcxx_requires_string(__s);
952 const size_type __size = this->size();
953 const size_type __osize = traits_type::length(__s);
954 const size_type __len = std::min(__size, __osize);
955 int __r = traits_type::compare(_M_data(), __s, __len);
956 if (!__r)
957 __r = _S_compare(__size, __osize);
958 return __r;
959 }
960
961 template<typename _CharT, typename _Traits, typename _Alloc>
962 int
963 basic_string <_CharT, _Traits, _Alloc>::
964 compare(size_type __pos, size_type __n1, const _CharT* __s) const
965 {
966 __glibcxx_requires_string(__s);
967 _M_check(__pos, "basic_string::compare");
968 __n1 = _M_limit(__pos, __n1);
969 const size_type __osize = traits_type::length(__s);
970 const size_type __len = std::min(__n1, __osize);
971 int __r = traits_type::compare(_M_data() + __pos, __s, __len);
972 if (!__r)
973 __r = _S_compare(__n1, __osize);
974 return __r;
975 }
976
977 template<typename _CharT, typename _Traits, typename _Alloc>
978 int
979 basic_string <_CharT, _Traits, _Alloc>::
980 compare(size_type __pos, size_type __n1, const _CharT* __s,
981 size_type __n2) const
982 {
983 __glibcxx_requires_string_len(__s, __n2);
984 _M_check(__pos, "basic_string::compare");
985 __n1 = _M_limit(__pos, __n1);
986 const size_type __len = std::min(__n1, __n2);
987 int __r = traits_type::compare(_M_data() + __pos, __s, __len);
988 if (!__r)
989 __r = _S_compare(__n1, __n2);
990 return __r;
991 }
992
993 // 21.3.7.9 basic_string::getline and operators
994 template<typename _CharT, typename _Traits, typename _Alloc>
995 basic_istream<_CharT, _Traits>&
996 operator>>(basic_istream<_CharT, _Traits>& __in,
997 basic_string<_CharT, _Traits, _Alloc>& __str)
998 {
999 typedef basic_istream<_CharT, _Traits> __istream_type;
1000 typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
1001 typedef typename __istream_type::ios_base __ios_base;
1002 typedef typename __istream_type::int_type __int_type;
1003 typedef typename __string_type::size_type __size_type;
1004 typedef ctype<_CharT> __ctype_type;
1005 typedef typename __ctype_type::ctype_base __ctype_base;
1006
1007 __size_type __extracted = 0;
1008 typename __ios_base::iostate __err = __ios_base::goodbit;
1009 typename __istream_type::sentry __cerb(__in, false);
1010 if (__cerb)
1011 {
1012 __try
1013 {
1014 // Avoid reallocation for common case.
1015 __str.erase();
1016 _CharT __buf[128];
1017 __size_type __len = 0;
1018 const streamsize __w = __in.width();
1019 const __size_type __n = __w > 0 ? static_cast<__size_type>(__w)
1020 : __str.max_size();
1021 const __ctype_type& __ct = use_facet<__ctype_type>(__in.getloc());
1022 const __int_type __eof = _Traits::eof();
1023 __int_type __c = __in.rdbuf()->sgetc();
1024
1025 while (__extracted < __n
1026 && !_Traits::eq_int_type(__c, __eof)
1027 && !__ct.is(__ctype_base::space,
1028 _Traits::to_char_type(__c)))
1029 {
1030 if (__len == sizeof(__buf) / sizeof(_CharT))
1031 {
1032 __str.append(__buf, sizeof(__buf) / sizeof(_CharT));
1033 __len = 0;
1034 }
1035 __buf[__len++] = _Traits::to_char_type(__c);
1036 ++__extracted;
1037 __c = __in.rdbuf()->snextc();
1038 }
1039 __str.append(__buf, __len);
1040
1041 if (_Traits::eq_int_type(__c, __eof))
1042 __err |= __ios_base::eofbit;
1043 __in.width(0);
1044 }
1045 __catch(__cxxabiv1::__forced_unwind&)
1046 {
1047 __in._M_setstate(__ios_base::badbit);
1048 __throw_exception_again;
1049 }
1050 __catch(...)
1051 {
1052 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1053 // 91. Description of operator>> and getline() for string<>
1054 // might cause endless loop
1055 __in._M_setstate(__ios_base::badbit);
1056 }
1057 }
1058 // 211. operator>>(istream&, string&) doesn't set failbit
1059 if (!__extracted)
1060 __err |= __ios_base::failbit;
1061 if (__err)
1062 __in.setstate(__err);
1063 return __in;
1064 }
1065
1066 template<typename _CharT, typename _Traits, typename _Alloc>
1067 basic_istream<_CharT, _Traits>&
1068 getline(basic_istream<_CharT, _Traits>& __in,
1069 basic_string<_CharT, _Traits, _Alloc>& __str, _CharT __delim)
1070 {
1071 typedef basic_istream<_CharT, _Traits> __istream_type;
1072 typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
1073 typedef typename __istream_type::ios_base __ios_base;
1074 typedef typename __istream_type::int_type __int_type;
1075 typedef typename __string_type::size_type __size_type;
1076
1077 __size_type __extracted = 0;
1078 const __size_type __n = __str.max_size();
1079 typename __ios_base::iostate __err = __ios_base::goodbit;
1080 typename __istream_type::sentry __cerb(__in, true);
1081 if (__cerb)
1082 {
1083 __try
1084 {
1085 __str.erase();
1086 const __int_type __idelim = _Traits::to_int_type(__delim);
1087 const __int_type __eof = _Traits::eof();
1088 __int_type __c = __in.rdbuf()->sgetc();
1089
1090 while (__extracted < __n
1091 && !_Traits::eq_int_type(__c, __eof)
1092 && !_Traits::eq_int_type(__c, __idelim))
1093 {
1094 __str += _Traits::to_char_type(__c);
1095 ++__extracted;
1096 __c = __in.rdbuf()->snextc();
1097 }
1098
1099 if (_Traits::eq_int_type(__c, __eof))
1100 __err |= __ios_base::eofbit;
1101 else if (_Traits::eq_int_type(__c, __idelim))
1102 {
1103 ++__extracted;
1104 __in.rdbuf()->sbumpc();
1105 }
1106 else
1107 __err |= __ios_base::failbit;
1108 }
1109 __catch(__cxxabiv1::__forced_unwind&)
1110 {
1111 __in._M_setstate(__ios_base::badbit);
1112 __throw_exception_again;
1113 }
1114 __catch(...)
1115 {
1116 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1117 // 91. Description of operator>> and getline() for string<>
1118 // might cause endless loop
1119 __in._M_setstate(__ios_base::badbit);
1120 }
1121 }
1122 if (!__extracted)
1123 __err |= __ios_base::failbit;
1124 if (__err)
1125 __in.setstate(__err);
1126 return __in;
1127 }
1128
1129 // Inhibit implicit instantiations for required instantiations,
1130 // which are defined via explicit instantiations elsewhere.
1131 #if _GLIBCXX_EXTERN_TEMPLATE > 0
1132 extern template class basic_string<char>;
1133 extern template
1134 basic_istream<char>&
1135 operator>>(basic_istream<char>&, string&);
1136 extern template
1137 basic_ostream<char>&
1138 operator<<(basic_ostream<char>&, const string&);
1139 extern template
1140 basic_istream<char>&
1141 getline(basic_istream<char>&, string&, char);
1142 extern template
1143 basic_istream<char>&
1144 getline(basic_istream<char>&, string&);
1145
1146 #ifdef _GLIBCXX_USE_WCHAR_T
1147 extern template class basic_string<wchar_t>;
1148 extern template
1149 basic_istream<wchar_t>&
1150 operator>>(basic_istream<wchar_t>&, wstring&);
1151 extern template
1152 basic_ostream<wchar_t>&
1153 operator<<(basic_ostream<wchar_t>&, const wstring&);
1154 extern template
1155 basic_istream<wchar_t>&
1156 getline(basic_istream<wchar_t>&, wstring&, wchar_t);
1157 extern template
1158 basic_istream<wchar_t>&
1159 getline(basic_istream<wchar_t>&, wstring&);
1160 #endif
1161 #endif
1162
1163 _GLIBCXX_END_NAMESPACE_VERSION
1164 } // namespace std
1165
1166 #endif