1// Components for manipulating sequences of characters -*- C++ -*-
2
3// Copyright (C) 1997-2024 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// Non-reference-counted implementation written by Paolo Carlini and
37// updated by Jonathan Wakely for ISO-14882-2011.
38
39#ifndef _BASIC_STRING_TCC
40#define _BASIC_STRING_TCC 1
41
42#pragma GCC system_header
43
44#include <bits/cxxabi_forced.h>
45
46namespace std _GLIBCXX_VISIBILITY(default)
47{
48_GLIBCXX_BEGIN_NAMESPACE_VERSION
49
50#if _GLIBCXX_USE_CXX11_ABI
51
52 template<typename _CharT, typename _Traits, typename _Alloc>
53 const typename basic_string<_CharT, _Traits, _Alloc>::size_type
54 basic_string<_CharT, _Traits, _Alloc>::npos;
55
56 template<typename _CharT, typename _Traits, typename _Alloc>
57 _GLIBCXX20_CONSTEXPR
58 void
59 basic_string<_CharT, _Traits, _Alloc>::
60 swap(basic_string& __s) _GLIBCXX_NOEXCEPT
61 {
62 if (this == std::__addressof(__s))
63 return;
64
65 _Alloc_traits::_S_on_swap(_M_get_allocator(), __s._M_get_allocator());
66
67 if (_M_is_local())
68 if (__s._M_is_local())
69 {
70 if (length() && __s.length())
71 {
72 _CharT __tmp_data[_S_local_capacity + 1];
73 traits_type::copy(__tmp_data, __s._M_local_buf,
74 __s.length() + 1);
75 traits_type::copy(__s._M_local_buf, _M_local_buf,
76 length() + 1);
77 traits_type::copy(_M_local_buf, __tmp_data,
78 __s.length() + 1);
79 }
80 else if (__s.length())
81 {
82 _M_init_local_buf();
83 traits_type::copy(_M_local_buf, __s._M_local_buf,
84 __s.length() + 1);
85 _M_length(length: __s.length());
86 __s._M_set_length(0);
87 return;
88 }
89 else if (length())
90 {
91 __s._M_init_local_buf();
92 traits_type::copy(__s._M_local_buf, _M_local_buf,
93 length() + 1);
94 __s._M_length(length());
95 _M_set_length(n: 0);
96 return;
97 }
98 }
99 else
100 {
101 const size_type __tmp_capacity = __s._M_allocated_capacity;
102 __s._M_init_local_buf();
103 traits_type::copy(__s._M_local_buf, _M_local_buf,
104 length() + 1);
105 _M_data(__s._M_data());
106 __s._M_data(__s._M_local_buf);
107 _M_capacity(capacity: __tmp_capacity);
108 }
109 else
110 {
111 const size_type __tmp_capacity = _M_allocated_capacity;
112 if (__s._M_is_local())
113 {
114 _M_init_local_buf();
115 traits_type::copy(_M_local_buf, __s._M_local_buf,
116 __s.length() + 1);
117 __s._M_data(_M_data());
118 _M_data(_M_local_buf);
119 }
120 else
121 {
122 pointer __tmp_ptr = _M_data();
123 _M_data(__s._M_data());
124 __s._M_data(__tmp_ptr);
125 _M_capacity(capacity: __s._M_allocated_capacity);
126 }
127 __s._M_capacity(__tmp_capacity);
128 }
129
130 const size_type __tmp_length = length();
131 _M_length(length: __s.length());
132 __s._M_length(__tmp_length);
133 }
134
135 template<typename _CharT, typename _Traits, typename _Alloc>
136 _GLIBCXX20_CONSTEXPR
137 typename basic_string<_CharT, _Traits, _Alloc>::pointer
138 basic_string<_CharT, _Traits, _Alloc>::
139 _M_create(size_type& __capacity, size_type __old_capacity)
140 {
141 // _GLIBCXX_RESOLVE_LIB_DEFECTS
142 // 83. String::npos vs. string::max_size()
143 if (__capacity > max_size())
144 std::__throw_length_error(__N("basic_string::_M_create"));
145
146 // The below implements an exponential growth policy, necessary to
147 // meet amortized linear time requirements of the library: see
148 // http://gcc.gnu.org/ml/libstdc++/2001-07/msg00085.html.
149 if (__capacity > __old_capacity && __capacity < 2 * __old_capacity)
150 {
151 __capacity = 2 * __old_capacity;
152 // Never allocate a string bigger than max_size.
153 if (__capacity > max_size())
154 __capacity = max_size();
155 }
156
157 // NB: Need an array of char_type[__capacity], plus a terminating
158 // null char_type() element.
159 return _S_allocate(a&: _M_get_allocator(), n: __capacity + 1);
160 }
161
162 // NB: This is the special case for Input Iterators, used in
163 // istreambuf_iterators, etc.
164 // Input Iterators have a cost structure very different from
165 // pointers, calling for a different coding style.
166 template<typename _CharT, typename _Traits, typename _Alloc>
167 template<typename _InIterator>
168 _GLIBCXX20_CONSTEXPR
169 void
170 basic_string<_CharT, _Traits, _Alloc>::
171 _M_construct(_InIterator __beg, _InIterator __end,
172 std::input_iterator_tag)
173 {
174 size_type __len = 0;
175 size_type __capacity = size_type(_S_local_capacity);
176
177 _M_init_local_buf();
178
179 while (__beg != __end && __len < __capacity)
180 {
181 _M_local_buf[__len++] = *__beg;
182 ++__beg;
183 }
184
185 struct _Guard
186 {
187 _GLIBCXX20_CONSTEXPR
188 explicit _Guard(basic_string* __s) : _M_guarded(__s) { }
189
190 _GLIBCXX20_CONSTEXPR
191 ~_Guard() { if (_M_guarded) _M_guarded->_M_dispose(); }
192
193 basic_string* _M_guarded;
194 } __guard(this);
195
196 while (__beg != __end)
197 {
198 if (__len == __capacity)
199 {
200 // Allocate more space.
201 __capacity = __len + 1;
202 pointer __another = _M_create(__capacity, old_capacity: __len);
203 this->_S_copy(__another, _M_data(), __len);
204 _M_dispose();
205 _M_data(__another);
206 _M_capacity(__capacity);
207 }
208 traits_type::assign(_M_data()[__len++], *__beg);
209 ++__beg;
210 }
211
212 __guard._M_guarded = 0;
213
214 _M_set_length(n: __len);
215 }
216
217 template<typename _CharT, typename _Traits, typename _Alloc>
218 template<typename _InIterator>
219 _GLIBCXX20_CONSTEXPR
220 void
221 basic_string<_CharT, _Traits, _Alloc>::
222 _M_construct(_InIterator __beg, _InIterator __end,
223 std::forward_iterator_tag)
224 {
225 size_type __dnew = static_cast<size_type>(std::distance(__beg, __end));
226
227 if (__dnew > size_type(_S_local_capacity))
228 {
229 _M_data(_M_create(capacity&: __dnew, old_capacity: size_type(0)));
230 _M_capacity(capacity: __dnew);
231 }
232 else
233 _M_init_local_buf();
234
235 // Check for out_of_range and length_error exceptions.
236 struct _Guard
237 {
238 _GLIBCXX20_CONSTEXPR
239 explicit _Guard(basic_string* __s) : _M_guarded(__s) { }
240
241 _GLIBCXX20_CONSTEXPR
242 ~_Guard() { if (_M_guarded) _M_guarded->_M_dispose(); }
243
244 basic_string* _M_guarded;
245 } __guard(this);
246
247 this->_S_copy_chars(_M_data(), __beg, __end);
248
249 __guard._M_guarded = 0;
250
251 _M_set_length(n: __dnew);
252 }
253
254 template<typename _CharT, typename _Traits, typename _Alloc>
255 _GLIBCXX20_CONSTEXPR
256 void
257 basic_string<_CharT, _Traits, _Alloc>::
258 _M_construct(size_type __n, _CharT __c)
259 {
260 if (__n > size_type(_S_local_capacity))
261 {
262 _M_data(_M_create(capacity&: __n, old_capacity: size_type(0)));
263 _M_capacity(capacity: __n);
264 }
265 else
266 _M_init_local_buf();
267
268 if (__n)
269 this->_S_assign(_M_data(), __n, __c);
270
271 _M_set_length(__n);
272 }
273
274 template<typename _CharT, typename _Traits, typename _Alloc>
275 _GLIBCXX20_CONSTEXPR
276 void
277 basic_string<_CharT, _Traits, _Alloc>::
278 _M_assign(const basic_string& __str)
279 {
280 if (this != std::__addressof(__str))
281 {
282 const size_type __rsize = __str.length();
283 const size_type __capacity = capacity();
284
285 if (__rsize > __capacity)
286 {
287 size_type __new_capacity = __rsize;
288 pointer __tmp = _M_create(capacity&: __new_capacity, old_capacity: __capacity);
289 _M_dispose();
290 _M_data(__tmp);
291 _M_capacity(capacity: __new_capacity);
292 }
293
294 if (__rsize)
295 this->_S_copy(_M_data(), __str._M_data(), __rsize);
296
297 _M_set_length(n: __rsize);
298 }
299 }
300
301 template<typename _CharT, typename _Traits, typename _Alloc>
302 _GLIBCXX20_CONSTEXPR
303 void
304 basic_string<_CharT, _Traits, _Alloc>::
305 reserve(size_type __res)
306 {
307 const size_type __capacity = capacity();
308 // _GLIBCXX_RESOLVE_LIB_DEFECTS
309 // 2968. Inconsistencies between basic_string reserve and
310 // vector/unordered_map/unordered_set reserve functions
311 // P0966 reserve should not shrink
312 if (__res <= __capacity)
313 return;
314
315 pointer __tmp = _M_create(capacity&: __res, old_capacity: __capacity);
316 this->_S_copy(__tmp, _M_data(), length() + 1);
317 _M_dispose();
318 _M_data(__tmp);
319 _M_capacity(capacity: __res);
320 }
321
322 template<typename _CharT, typename _Traits, typename _Alloc>
323 _GLIBCXX20_CONSTEXPR
324 void
325 basic_string<_CharT, _Traits, _Alloc>::
326 _M_mutate(size_type __pos, size_type __len1, const _CharT* __s,
327 size_type __len2)
328 {
329 const size_type __how_much = length() - __pos - __len1;
330
331 size_type __new_capacity = length() + __len2 - __len1;
332 pointer __r = _M_create(capacity&: __new_capacity, old_capacity: capacity());
333
334 if (__pos)
335 this->_S_copy(__r, _M_data(), __pos);
336 if (__s && __len2)
337 this->_S_copy(__r + __pos, __s, __len2);
338 if (__how_much)
339 this->_S_copy(__r + __pos + __len2,
340 _M_data() + __pos + __len1, __how_much);
341
342 _M_dispose();
343 _M_data(__r);
344 _M_capacity(capacity: __new_capacity);
345 }
346
347 template<typename _CharT, typename _Traits, typename _Alloc>
348 _GLIBCXX20_CONSTEXPR
349 void
350 basic_string<_CharT, _Traits, _Alloc>::
351 _M_erase(size_type __pos, size_type __n)
352 {
353 const size_type __how_much = length() - __pos - __n;
354
355 if (__how_much && __n)
356 this->_S_move(_M_data() + __pos, _M_data() + __pos + __n, __how_much);
357
358 _M_set_length(n: length() - __n);
359 }
360
361 template<typename _CharT, typename _Traits, typename _Alloc>
362 _GLIBCXX20_CONSTEXPR
363 void
364 basic_string<_CharT, _Traits, _Alloc>::
365 reserve()
366 {
367 if (_M_is_local())
368 return;
369
370 const size_type __length = length();
371 const size_type __capacity = _M_allocated_capacity;
372
373 if (__length <= size_type(_S_local_capacity))
374 {
375 _M_init_local_buf();
376 this->_S_copy(_M_local_buf, _M_data(), __length + 1);
377 _M_destroy(size: __capacity);
378 _M_data(_M_local_data());
379 }
380#if __cpp_exceptions
381 else if (__length < __capacity)
382 try
383 {
384 pointer __tmp = _S_allocate(_M_get_allocator(), __length + 1);
385 this->_S_copy(__tmp, _M_data(), __length + 1);
386 _M_dispose();
387 _M_data(__tmp);
388 _M_capacity(__length);
389 }
390 catch (const __cxxabiv1::__forced_unwind&)
391 { throw; }
392 catch (...)
393 { /* swallow the exception */ }
394#endif
395 }
396
397 template<typename _CharT, typename _Traits, typename _Alloc>
398 _GLIBCXX20_CONSTEXPR
399 void
400 basic_string<_CharT, _Traits, _Alloc>::
401 resize(size_type __n, _CharT __c)
402 {
403 const size_type __size = this->size();
404 if (__size < __n)
405 this->append(__n - __size, __c);
406 else if (__n < __size)
407 this->_M_set_length(__n);
408 }
409
410 template<typename _CharT, typename _Traits, typename _Alloc>
411 _GLIBCXX20_CONSTEXPR
412 basic_string<_CharT, _Traits, _Alloc>&
413 basic_string<_CharT, _Traits, _Alloc>::
414 _M_append(const _CharT* __s, size_type __n)
415 {
416 const size_type __len = __n + this->size();
417
418 if (__len <= this->capacity())
419 {
420 if (__n)
421 this->_S_copy(this->_M_data() + this->size(), __s, __n);
422 }
423 else
424 this->_M_mutate(this->size(), size_type(0), __s, __n);
425
426 this->_M_set_length(__len);
427 return *this;
428 }
429
430 template<typename _CharT, typename _Traits, typename _Alloc>
431 template<typename _InputIterator>
432 _GLIBCXX20_CONSTEXPR
433 basic_string<_CharT, _Traits, _Alloc>&
434 basic_string<_CharT, _Traits, _Alloc>::
435 _M_replace_dispatch(const_iterator __i1, const_iterator __i2,
436 _InputIterator __k1, _InputIterator __k2,
437 std::__false_type)
438 {
439 // _GLIBCXX_RESOLVE_LIB_DEFECTS
440 // 2788. unintentionally require a default constructible allocator
441 const basic_string __s(__k1, __k2, this->get_allocator());
442 const size_type __n1 = __i2 - __i1;
443 return _M_replace(pos: __i1 - begin(), len1: __n1, s: __s._M_data(),
444 len2: __s.size());
445 }
446
447 template<typename _CharT, typename _Traits, typename _Alloc>
448 _GLIBCXX20_CONSTEXPR
449 basic_string<_CharT, _Traits, _Alloc>&
450 basic_string<_CharT, _Traits, _Alloc>::
451 _M_replace_aux(size_type __pos1, size_type __n1, size_type __n2,
452 _CharT __c)
453 {
454 _M_check_length(__n1, __n2, s: "basic_string::_M_replace_aux");
455
456 const size_type __old_size = this->size();
457 const size_type __new_size = __old_size + __n2 - __n1;
458
459 if (__new_size <= this->capacity())
460 {
461 pointer __p = this->_M_data() + __pos1;
462
463 const size_type __how_much = __old_size - __pos1 - __n1;
464 if (__how_much && __n1 != __n2)
465 this->_S_move(__p + __n2, __p + __n1, __how_much);
466 }
467 else
468 this->_M_mutate(__pos1, __n1, 0, __n2);
469
470 if (__n2)
471 this->_S_assign(this->_M_data() + __pos1, __n2, __c);
472
473 this->_M_set_length(__new_size);
474 return *this;
475 }
476
477 template<typename _CharT, typename _Traits, typename _Alloc>
478 __attribute__((__noinline__, __noclone__, __cold__)) void
479 basic_string<_CharT, _Traits, _Alloc>::
480 _M_replace_cold(pointer __p, size_type __len1, const _CharT* __s,
481 const size_type __len2, const size_type __how_much)
482 {
483 // Work in-place.
484 if (__len2 && __len2 <= __len1)
485 this->_S_move(__p, __s, __len2);
486 if (__how_much && __len1 != __len2)
487 this->_S_move(__p + __len2, __p + __len1, __how_much);
488 if (__len2 > __len1)
489 {
490 if (__s + __len2 <= __p + __len1)
491 this->_S_move(__p, __s, __len2);
492 else if (__s >= __p + __len1)
493 {
494 // Hint to middle end that __p and __s overlap
495 // (PR 98465).
496 const size_type __poff = (__s - __p) + (__len2 - __len1);
497 this->_S_copy(__p, __p + __poff, __len2);
498 }
499 else
500 {
501 const size_type __nleft = (__p + __len1) - __s;
502 this->_S_move(__p, __s, __nleft);
503 this->_S_copy(__p + __nleft, __p + __len2, __len2 - __nleft);
504 }
505 }
506 }
507
508 template<typename _CharT, typename _Traits, typename _Alloc>
509 _GLIBCXX20_CONSTEXPR
510 basic_string<_CharT, _Traits, _Alloc>&
511 basic_string<_CharT, _Traits, _Alloc>::
512 _M_replace(size_type __pos, size_type __len1, const _CharT* __s,
513 const size_type __len2)
514 {
515 _M_check_length(n1: __len1, n2: __len2, s: "basic_string::_M_replace");
516
517 const size_type __old_size = this->size();
518 const size_type __new_size = __old_size + __len2 - __len1;
519
520 if (__new_size <= this->capacity())
521 {
522 pointer __p = this->_M_data() + __pos;
523
524 const size_type __how_much = __old_size - __pos - __len1;
525#if __cpp_lib_is_constant_evaluated
526 if (std::is_constant_evaluated())
527 {
528 auto __newp = _S_allocate(_M_get_allocator(), __new_size);
529 _S_copy(__newp, this->_M_data(), __pos);
530 _S_copy(__newp + __pos, __s, __len2);
531 _S_copy(__newp + __pos + __len2, __p + __len1, __how_much);
532 _S_copy(this->_M_data(), __newp, __new_size);
533 this->_M_get_allocator().deallocate(__newp, __new_size);
534 }
535 else
536#endif
537 if (__builtin_expect(_M_disjunct(__s), true))
538 {
539 if (__how_much && __len1 != __len2)
540 this->_S_move(__p + __len2, __p + __len1, __how_much);
541 if (__len2)
542 this->_S_copy(__p, __s, __len2);
543 }
544 else
545 _M_replace_cold(__p, __len1, __s, __len2, __how_much);
546 }
547 else
548 this->_M_mutate(__pos, __len1, __s, __len2);
549
550 this->_M_set_length(__new_size);
551 return *this;
552 }
553
554 template<typename _CharT, typename _Traits, typename _Alloc>
555 _GLIBCXX20_CONSTEXPR
556 typename basic_string<_CharT, _Traits, _Alloc>::size_type
557 basic_string<_CharT, _Traits, _Alloc>::
558 copy(_CharT* __s, size_type __n, size_type __pos) const
559 {
560 _M_check(__pos, s: "basic_string::copy");
561 __n = _M_limit(__pos, off: __n);
562 __glibcxx_requires_string_len(__s, __n);
563 if (__n)
564 _S_copy(d: __s, s: _M_data() + __pos, __n);
565 // 21.3.5.7 par 3: do not append null. (good.)
566 return __n;
567 }
568
569#ifdef __glibcxx_string_resize_and_overwrite // C++ >= 23
570 template<typename _CharT, typename _Traits, typename _Alloc>
571 template<typename _Operation>
572 [[__gnu__::__always_inline__]]
573 constexpr void
574 basic_string<_CharT, _Traits, _Alloc>::
575 __resize_and_overwrite(const size_type __n, _Operation __op)
576 { resize_and_overwrite<_Operation&>(__n, __op); }
577#endif
578
579#if __cplusplus >= 201103L
580 template<typename _CharT, typename _Traits, typename _Alloc>
581 template<typename _Operation>
582 _GLIBCXX20_CONSTEXPR void
583 basic_string<_CharT, _Traits, _Alloc>::
584#ifdef __glibcxx_string_resize_and_overwrite // C++ >= 23
585 resize_and_overwrite(const size_type __n, _Operation __op)
586#else
587 __resize_and_overwrite(const size_type __n, _Operation __op)
588#endif
589 {
590 reserve(__n);
591 _CharT* const __p = _M_data();
592#if __cpp_lib_is_constant_evaluated
593 if (std::__is_constant_evaluated() && __n > size())
594 traits_type::assign(__p + size(), __n - size(), _CharT());
595#endif
596 struct _Terminator {
597 _GLIBCXX20_CONSTEXPR ~_Terminator() { _M_this->_M_set_length(_M_r); }
598 basic_string* _M_this;
599 size_type _M_r;
600 };
601 _Terminator __term{this, 0};
602 auto __r = std::move(__op)(__p + 0, __n + 0);
603#ifdef __cpp_lib_concepts
604 static_assert(ranges::__detail::__is_integer_like<decltype(__r)>);
605#else
606 static_assert(__gnu_cxx::__is_integer_nonstrict<decltype(__r)>::__value,
607 "resize_and_overwrite operation must return an integer");
608#endif
609 _GLIBCXX_DEBUG_ASSERT(__r >= 0 && __r <= __n);
610 __term._M_r = size_type(__r);
611 if (__term._M_r > __n)
612 __builtin_unreachable();
613 }
614#endif // C++11
615
616#endif // _GLIBCXX_USE_CXX11_ABI
617
618#if __glibcxx_constexpr_string >= 201907L
619# define _GLIBCXX_STRING_CONSTEXPR constexpr
620#else
621# define _GLIBCXX_STRING_CONSTEXPR
622#endif
623 template<typename _CharT, typename _Traits, typename _Alloc>
624 _GLIBCXX_STRING_CONSTEXPR
625 typename basic_string<_CharT, _Traits, _Alloc>::size_type
626 basic_string<_CharT, _Traits, _Alloc>::
627 find(const _CharT* __s, size_type __pos, size_type __n) const
628 _GLIBCXX_NOEXCEPT
629 {
630 __glibcxx_requires_string_len(__s, __n);
631 const size_type __size = this->size();
632
633 if (__n == 0)
634 return __pos <= __size ? __pos : npos;
635 if (__pos >= __size)
636 return npos;
637
638 const _CharT __elem0 = __s[0];
639 const _CharT* const __data = data();
640 const _CharT* __first = __data + __pos;
641 const _CharT* const __last = __data + __size;
642 size_type __len = __size - __pos;
643
644 while (__len >= __n)
645 {
646 // Find the first occurrence of __elem0:
647 __first = traits_type::find(__first, __len - __n + 1, __elem0);
648 if (!__first)
649 return npos;
650 // Compare the full strings from the first occurrence of __elem0.
651 // We already know that __first[0] == __s[0] but compare them again
652 // anyway because __s is probably aligned, which helps memcmp.
653 if (traits_type::compare(__first, __s, __n) == 0)
654 return __first - __data;
655 __len = __last - ++__first;
656 }
657 return npos;
658 }
659
660 template<typename _CharT, typename _Traits, typename _Alloc>
661 _GLIBCXX_STRING_CONSTEXPR
662 typename basic_string<_CharT, _Traits, _Alloc>::size_type
663 basic_string<_CharT, _Traits, _Alloc>::
664 find(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
665 {
666 size_type __ret = npos;
667 const size_type __size = this->size();
668 if (__pos < __size)
669 {
670 const _CharT* __data = _M_data();
671 const size_type __n = __size - __pos;
672 const _CharT* __p = traits_type::find(__data + __pos, __n, __c);
673 if (__p)
674 __ret = __p - __data;
675 }
676 return __ret;
677 }
678
679 template<typename _CharT, typename _Traits, typename _Alloc>
680 _GLIBCXX_STRING_CONSTEXPR
681 typename basic_string<_CharT, _Traits, _Alloc>::size_type
682 basic_string<_CharT, _Traits, _Alloc>::
683 rfind(const _CharT* __s, size_type __pos, size_type __n) const
684 _GLIBCXX_NOEXCEPT
685 {
686 __glibcxx_requires_string_len(__s, __n);
687 const size_type __size = this->size();
688 if (__n <= __size)
689 {
690 __pos = std::min(size_type(__size - __n), __pos);
691 const _CharT* __data = _M_data();
692 do
693 {
694 if (traits_type::compare(__data + __pos, __s, __n) == 0)
695 return __pos;
696 }
697 while (__pos-- > 0);
698 }
699 return npos;
700 }
701
702 template<typename _CharT, typename _Traits, typename _Alloc>
703 _GLIBCXX_STRING_CONSTEXPR
704 typename basic_string<_CharT, _Traits, _Alloc>::size_type
705 basic_string<_CharT, _Traits, _Alloc>::
706 rfind(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
707 {
708 size_type __size = this->size();
709 if (__size)
710 {
711 if (--__size > __pos)
712 __size = __pos;
713 for (++__size; __size-- > 0; )
714 if (traits_type::eq(_M_data()[__size], __c))
715 return __size;
716 }
717 return npos;
718 }
719
720 template<typename _CharT, typename _Traits, typename _Alloc>
721 _GLIBCXX_STRING_CONSTEXPR
722 typename basic_string<_CharT, _Traits, _Alloc>::size_type
723 basic_string<_CharT, _Traits, _Alloc>::
724 find_first_of(const _CharT* __s, size_type __pos, size_type __n) const
725 _GLIBCXX_NOEXCEPT
726 {
727 __glibcxx_requires_string_len(__s, __n);
728 for (; __n && __pos < this->size(); ++__pos)
729 {
730 const _CharT* __p = traits_type::find(__s, __n, _M_data()[__pos]);
731 if (__p)
732 return __pos;
733 }
734 return npos;
735 }
736
737 template<typename _CharT, typename _Traits, typename _Alloc>
738 _GLIBCXX_STRING_CONSTEXPR
739 typename basic_string<_CharT, _Traits, _Alloc>::size_type
740 basic_string<_CharT, _Traits, _Alloc>::
741 find_last_of(const _CharT* __s, size_type __pos, size_type __n) const
742 _GLIBCXX_NOEXCEPT
743 {
744 __glibcxx_requires_string_len(__s, __n);
745 size_type __size = this->size();
746 if (__size && __n)
747 {
748 if (--__size > __pos)
749 __size = __pos;
750 do
751 {
752 if (traits_type::find(__s, __n, _M_data()[__size]))
753 return __size;
754 }
755 while (__size-- != 0);
756 }
757 return npos;
758 }
759
760 template<typename _CharT, typename _Traits, typename _Alloc>
761 _GLIBCXX_STRING_CONSTEXPR
762 typename basic_string<_CharT, _Traits, _Alloc>::size_type
763 basic_string<_CharT, _Traits, _Alloc>::
764 find_first_not_of(const _CharT* __s, size_type __pos, size_type __n) const
765 _GLIBCXX_NOEXCEPT
766 {
767 __glibcxx_requires_string_len(__s, __n);
768 for (; __pos < this->size(); ++__pos)
769 if (!traits_type::find(__s, __n, _M_data()[__pos]))
770 return __pos;
771 return npos;
772 }
773
774 template<typename _CharT, typename _Traits, typename _Alloc>
775 _GLIBCXX_STRING_CONSTEXPR
776 typename basic_string<_CharT, _Traits, _Alloc>::size_type
777 basic_string<_CharT, _Traits, _Alloc>::
778 find_first_not_of(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
779 {
780 for (; __pos < this->size(); ++__pos)
781 if (!traits_type::eq(_M_data()[__pos], __c))
782 return __pos;
783 return npos;
784 }
785
786 template<typename _CharT, typename _Traits, typename _Alloc>
787 _GLIBCXX_STRING_CONSTEXPR
788 typename basic_string<_CharT, _Traits, _Alloc>::size_type
789 basic_string<_CharT, _Traits, _Alloc>::
790 find_last_not_of(const _CharT* __s, size_type __pos, size_type __n) const
791 _GLIBCXX_NOEXCEPT
792 {
793 __glibcxx_requires_string_len(__s, __n);
794 size_type __size = this->size();
795 if (__size)
796 {
797 if (--__size > __pos)
798 __size = __pos;
799 do
800 {
801 if (!traits_type::find(__s, __n, _M_data()[__size]))
802 return __size;
803 }
804 while (__size--);
805 }
806 return npos;
807 }
808
809 template<typename _CharT, typename _Traits, typename _Alloc>
810 _GLIBCXX_STRING_CONSTEXPR
811 typename basic_string<_CharT, _Traits, _Alloc>::size_type
812 basic_string<_CharT, _Traits, _Alloc>::
813 find_last_not_of(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
814 {
815 size_type __size = this->size();
816 if (__size)
817 {
818 if (--__size > __pos)
819 __size = __pos;
820 do
821 {
822 if (!traits_type::eq(_M_data()[__size], __c))
823 return __size;
824 }
825 while (__size--);
826 }
827 return npos;
828 }
829
830#undef _GLIBCXX_STRING_CONSTEXPR
831
832 // 21.3.7.9 basic_string::getline and operators
833 template<typename _CharT, typename _Traits, typename _Alloc>
834 basic_istream<_CharT, _Traits>&
835 operator>>(basic_istream<_CharT, _Traits>& __in,
836 basic_string<_CharT, _Traits, _Alloc>& __str)
837 {
838 typedef basic_istream<_CharT, _Traits> __istream_type;
839 typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
840 typedef typename __istream_type::ios_base __ios_base;
841 typedef typename __istream_type::int_type __int_type;
842 typedef typename __string_type::size_type __size_type;
843 typedef ctype<_CharT> __ctype_type;
844 typedef typename __ctype_type::ctype_base __ctype_base;
845
846 __size_type __extracted = 0;
847 typename __ios_base::iostate __err = __ios_base::goodbit;
848 typename __istream_type::sentry __cerb(__in, false);
849 if (__cerb)
850 {
851 __try
852 {
853 // Avoid reallocation for common case.
854 __str.erase();
855 _CharT __buf[128];
856 __size_type __len = 0;
857 const streamsize __w = __in.width();
858 const __size_type __n = __w > 0 ? static_cast<__size_type>(__w)
859 : __str.max_size();
860 const __ctype_type& __ct = use_facet<__ctype_type>(__in.getloc());
861 const __int_type __eof = _Traits::eof();
862 __int_type __c = __in.rdbuf()->sgetc();
863
864 while (__extracted < __n
865 && !_Traits::eq_int_type(__c, __eof)
866 && !__ct.is(__ctype_base::space,
867 _Traits::to_char_type(__c)))
868 {
869 if (__len == sizeof(__buf) / sizeof(_CharT))
870 {
871 __str.append(__buf, sizeof(__buf) / sizeof(_CharT));
872 __len = 0;
873 }
874 __buf[__len++] = _Traits::to_char_type(__c);
875 ++__extracted;
876 __c = __in.rdbuf()->snextc();
877 }
878 __str.append(__buf, __len);
879
880 if (__extracted < __n && _Traits::eq_int_type(__c, __eof))
881 __err |= __ios_base::eofbit;
882 __in.width(0);
883 }
884 __catch(__cxxabiv1::__forced_unwind&)
885 {
886 __in._M_setstate(__ios_base::badbit);
887 __throw_exception_again;
888 }
889 __catch(...)
890 {
891 // _GLIBCXX_RESOLVE_LIB_DEFECTS
892 // 91. Description of operator>> and getline() for string<>
893 // might cause endless loop
894 __in._M_setstate(__ios_base::badbit);
895 }
896 }
897 // 211. operator>>(istream&, string&) doesn't set failbit
898 if (!__extracted)
899 __err |= __ios_base::failbit;
900 if (__err)
901 __in.setstate(__err);
902 return __in;
903 }
904
905 template<typename _CharT, typename _Traits, typename _Alloc>
906 basic_istream<_CharT, _Traits>&
907 getline(basic_istream<_CharT, _Traits>& __in,
908 basic_string<_CharT, _Traits, _Alloc>& __str, _CharT __delim)
909 {
910 typedef basic_istream<_CharT, _Traits> __istream_type;
911 typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
912 typedef typename __istream_type::ios_base __ios_base;
913 typedef typename __istream_type::int_type __int_type;
914 typedef typename __string_type::size_type __size_type;
915
916 __size_type __extracted = 0;
917 const __size_type __n = __str.max_size();
918 typename __ios_base::iostate __err = __ios_base::goodbit;
919 typename __istream_type::sentry __cerb(__in, true);
920 if (__cerb)
921 {
922 __try
923 {
924 __str.erase();
925 const __int_type __idelim = _Traits::to_int_type(__delim);
926 const __int_type __eof = _Traits::eof();
927 __int_type __c = __in.rdbuf()->sgetc();
928
929 while (__extracted < __n
930 && !_Traits::eq_int_type(__c, __eof)
931 && !_Traits::eq_int_type(__c, __idelim))
932 {
933 __str += _Traits::to_char_type(__c);
934 ++__extracted;
935 __c = __in.rdbuf()->snextc();
936 }
937
938 if (_Traits::eq_int_type(__c, __eof))
939 __err |= __ios_base::eofbit;
940 else if (_Traits::eq_int_type(__c, __idelim))
941 {
942 ++__extracted;
943 __in.rdbuf()->sbumpc();
944 }
945 else
946 __err |= __ios_base::failbit;
947 }
948 __catch(__cxxabiv1::__forced_unwind&)
949 {
950 __in._M_setstate(__ios_base::badbit);
951 __throw_exception_again;
952 }
953 __catch(...)
954 {
955 // _GLIBCXX_RESOLVE_LIB_DEFECTS
956 // 91. Description of operator>> and getline() for string<>
957 // might cause endless loop
958 __in._M_setstate(__ios_base::badbit);
959 }
960 }
961 if (!__extracted)
962 __err |= __ios_base::failbit;
963 if (__err)
964 __in.setstate(__err);
965 return __in;
966 }
967
968 // Inhibit implicit instantiations for required instantiations,
969 // which are defined via explicit instantiations elsewhere.
970#if _GLIBCXX_EXTERN_TEMPLATE
971 // The explicit instantiation definitions in src/c++11/string-inst.cc and
972 // src/c++17/string-inst.cc only instantiate the members required for C++17
973 // and earlier standards (so not C++20's starts_with and ends_with).
974 // Suppress the explicit instantiation declarations for C++20, so C++20
975 // code will implicitly instantiate std::string and std::wstring as needed.
976# if __cplusplus <= 201703L && _GLIBCXX_EXTERN_TEMPLATE > 0
977 extern template class basic_string<char>;
978# elif ! _GLIBCXX_USE_CXX11_ABI
979 // Still need to prevent implicit instantiation of the COW empty rep,
980 // to ensure the definition in libstdc++.so is unique (PR 86138).
981 extern template basic_string<char>::size_type
982 basic_string<char>::_Rep::_S_empty_rep_storage[];
983# elif _GLIBCXX_EXTERN_TEMPLATE > 0
984 // Export _M_replace_cold even for C++20.
985 extern template void
986 basic_string<char>::_M_replace_cold(char *, size_type, const char*,
987 const size_type, const size_type);
988# endif
989
990 extern template
991 basic_istream<char>&
992 operator>>(basic_istream<char>&, string&);
993 extern template
994 basic_ostream<char>&
995 operator<<(basic_ostream<char>&, const string&);
996 extern template
997 basic_istream<char>&
998 getline(basic_istream<char>&, string&, char);
999 extern template
1000 basic_istream<char>&
1001 getline(basic_istream<char>&, string&);
1002
1003#ifdef _GLIBCXX_USE_WCHAR_T
1004# if __cplusplus <= 201703L && _GLIBCXX_EXTERN_TEMPLATE > 0
1005 extern template class basic_string<wchar_t>;
1006# elif ! _GLIBCXX_USE_CXX11_ABI
1007 extern template basic_string<wchar_t>::size_type
1008 basic_string<wchar_t>::_Rep::_S_empty_rep_storage[];
1009# elif _GLIBCXX_EXTERN_TEMPLATE > 0
1010 // Export _M_replace_cold even for C++20.
1011 extern template void
1012 basic_string<wchar_t>::_M_replace_cold(wchar_t*, size_type, const wchar_t*,
1013 const size_type, const size_type);
1014# endif
1015
1016 extern template
1017 basic_istream<wchar_t>&
1018 operator>>(basic_istream<wchar_t>&, wstring&);
1019 extern template
1020 basic_ostream<wchar_t>&
1021 operator<<(basic_ostream<wchar_t>&, const wstring&);
1022 extern template
1023 basic_istream<wchar_t>&
1024 getline(basic_istream<wchar_t>&, wstring&, wchar_t);
1025 extern template
1026 basic_istream<wchar_t>&
1027 getline(basic_istream<wchar_t>&, wstring&);
1028#endif // _GLIBCXX_USE_WCHAR_T
1029#endif // _GLIBCXX_EXTERN_TEMPLATE
1030
1031_GLIBCXX_END_NAMESPACE_VERSION
1032} // namespace std
1033
1034#endif
1035