libstdc++-v3/include/bits/basic_string.tcc

   1 // Components for manipulating sequences of characters -*- C++ -*-
   2
   3 // Copyright (C) 1997-2015 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
  46 namespace 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     void
  58     basic_string<_CharT, _Traits, _Alloc>::
  59     swap(basic_string& __s) _GLIBCXX_NOEXCEPT
  60     {
  61       if (this == &__s)
  62         return;
  63
  64       // _GLIBCXX_RESOLVE_LIB_DEFECTS
  65       // 431. Swapping containers with unequal allocators.
  66       // TODO propagation traits
  67       std::__alloc_swap<allocator_type>::_S_do_it(_M_get_allocator(),
  68                                                   __s._M_get_allocator());
  69
  70       if (_M_is_local())
  71         if (__s._M_is_local())
  72           {
  73             if (length() && __s.length())
  74               {
  75                 _CharT __tmp_data[_S_local_capacity + 1];
  76                 traits_type::copy(__tmp_data, __s._M_local_buf,
  77                                   _S_local_capacity + 1);
  78                 traits_type::copy(__s._M_local_buf, _M_local_buf,
  79                                   _S_local_capacity + 1);
  80                 traits_type::copy(_M_local_buf, __tmp_data,
  81                                   _S_local_capacity + 1);
  82               }
  83             else if (__s.length())
  84               {
  85                 traits_type::copy(_M_local_buf, __s._M_local_buf,
  86                                   _S_local_capacity + 1);
  87                 _M_length(__s.length());
  88                 __s._M_set_length(0);
  89                 return;
  90               }
  91             else if (length())
  92               {
  93                 traits_type::copy(__s._M_local_buf, _M_local_buf,
  94                                   _S_local_capacity + 1);
  95                 __s._M_length(length());
  96                 _M_set_length(0);
  97                 return;
  98               }
  99           }
 100         else
 101           {
 102             const size_type __tmp_capacity = __s._M_allocated_capacity;
 103             traits_type::copy(__s._M_local_buf, _M_local_buf,
 104                               _S_local_capacity + 1);
 105             _M_data(__s._M_data());
 106             __s._M_data(__s._M_local_buf);
 107             _M_capacity(__tmp_capacity);
 108           }
 109       else
 110         {
 111           const size_type __tmp_capacity = _M_allocated_capacity;
 112           if (__s._M_is_local())
 113             {
 114               traits_type::copy(_M_local_buf, __s._M_local_buf,
 115                                 _S_local_capacity + 1);
 116               __s._M_data(_M_data());
 117               _M_data(_M_local_buf);
 118             }
 119           else
 120             {
 121               pointer __tmp_ptr = _M_data();
 122               _M_data(__s._M_data());
 123               __s._M_data(__tmp_ptr);
 124               _M_capacity(__s._M_allocated_capacity);
 125             }
 126           __s._M_capacity(__tmp_capacity);
 127         }
 128
 129       const size_type __tmp_length = length();
 130       _M_length(__s.length());
 131       __s._M_length(__tmp_length);
 132     }
 133
 134   template<typename _CharT, typename _Traits, typename _Alloc>
 135     typename basic_string<_CharT, _Traits, _Alloc>::pointer
 136     basic_string<_CharT, _Traits, _Alloc>::
 137     _M_create(size_type& __capacity, size_type __old_capacity)
 138     {
 139       // _GLIBCXX_RESOLVE_LIB_DEFECTS
 140       // 83.  String::npos vs. string::max_size()
 141       if (__capacity > max_size())
 142         std::__throw_length_error(__N("basic_string::_M_create"));
 143
 144       // The below implements an exponential growth policy, necessary to
 145       // meet amortized linear time requirements of the library: see
 146       // http://gcc.gnu.org/ml/libstdc++/2001-07/msg00085.html.
 147       if (__capacity > __old_capacity && __capacity < 2 * __old_capacity)
 148         {
 149           __capacity = 2 * __old_capacity;
 150           // Never allocate a string bigger than max_size.
 151           if (__capacity > max_size())
 152             __capacity = max_size();
 153         }
 154
 155       // NB: Need an array of char_type[__capacity], plus a terminating
 156       // null char_type() element.
 157       return _Alloc_traits::allocate(_M_get_allocator(), __capacity + 1);
 158     }
 159
 160   // NB: This is the special case for Input Iterators, used in
 161   // istreambuf_iterators, etc.
 162   // Input Iterators have a cost structure very different from
 163   // pointers, calling for a different coding style.
 164   template<typename _CharT, typename _Traits, typename _Alloc>
 165     template<typename _InIterator>
 166       void
 167       basic_string<_CharT, _Traits, _Alloc>::
 168       _M_construct(_InIterator __beg, _InIterator __end,
 169                    std::input_iterator_tag)
 170       {
 171         size_type __len = 0;
 172         size_type __capacity = size_type(_S_local_capacity);
 173
 174         while (__beg != __end && __len < __capacity)
 175           {
 176             _M_data()[__len++] = *__beg;
 177             ++__beg;
 178           }
 179
 180         __try
 181           {
 182             while (__beg != __end)
 183               {
 184                 if (__len == __capacity)
 185                   {
 186                     // Allocate more space.
 187                     __capacity = __len + 1;
 188                     pointer __another = _M_create(__capacity, __len);
 189                     this->_S_copy(__another, _M_data(), __len);
 190                     _M_dispose();
 191                     _M_data(__another);
 192                     _M_capacity(__capacity);
 193                   }
 194                 _M_data()[__len++] = *__beg;
 195                 ++__beg;
 196               }
 197           }
 198         __catch(...)
 199           {
 200             _M_dispose();
 201             __throw_exception_again;
 202           }
 203
 204         _M_set_length(__len);
 205       }
 206
 207   template<typename _CharT, typename _Traits, typename _Alloc>
 208     template<typename _InIterator>
 209       void
 210       basic_string<_CharT, _Traits, _Alloc>::
 211       _M_construct(_InIterator __beg, _InIterator __end,
 212                    std::forward_iterator_tag)
 213       {
 214         // NB: Not required, but considered best practice.
 215         if (__gnu_cxx::__is_null_pointer(__beg) && __beg != __end)
 216           std::__throw_logic_error(__N("basic_string::"
 217                                        "_M_construct null not valid"));
 218
 219         size_type __dnew = static_cast<size_type>(std::distance(__beg, __end));
 220
 221         if (__dnew > size_type(_S_local_capacity))
 222           {
 223             _M_data(_M_create(__dnew, size_type(0)));
 224             _M_capacity(__dnew);
 225           }
 226
 227         // Check for out_of_range and length_error exceptions.
 228         __try
 229           { this->_S_copy_chars(_M_data(), __beg, __end); }
 230         __catch(...)
 231           {
 232             _M_dispose();
 233             __throw_exception_again;
 234           }
 235
 236         _M_set_length(__dnew);
 237       }
 238
 239   template<typename _CharT, typename _Traits, typename _Alloc>
 240     void
 241     basic_string<_CharT, _Traits, _Alloc>::
 242     _M_construct(size_type __n, _CharT __c)
 243     {
 244       if (__n > size_type(_S_local_capacity))
 245         {
 246           _M_data(_M_create(__n, size_type(0)));
 247           _M_capacity(__n);
 248         }
 249
 250       if (__n)
 251         this->_S_assign(_M_data(), __n, __c);
 252
 253       _M_set_length(__n);
 254     }
 255
 256   template<typename _CharT, typename _Traits, typename _Alloc>
 257     void
 258     basic_string<_CharT, _Traits, _Alloc>::
 259     _M_assign(const basic_string& __str)
 260     {
 261       if (this != &__str)
 262         {
 263           const size_type __rsize = __str.length();
 264           const size_type __capacity = capacity();
 265
 266           if (__rsize > __capacity)
 267             {
 268               size_type __new_capacity = __rsize;
 269               pointer __tmp = _M_create(__new_capacity, __capacity);
 270               _M_dispose();
 271               _M_data(__tmp);
 272               _M_capacity(__new_capacity);
 273             }
 274
 275           if (__rsize)
 276             this->_S_copy(_M_data(), __str._M_data(), __rsize);
 277
 278           _M_set_length(__rsize);
 279         }
 280     }
 281
 282   template<typename _CharT, typename _Traits, typename _Alloc>
 283     void
 284     basic_string<_CharT, _Traits, _Alloc>::
 285     reserve(size_type __res)
 286     {
 287       // Make sure we don't shrink below the current size.
 288       if (__res < length())
 289         __res = length();
 290
 291       const size_type __capacity = capacity();
 292       if (__res != __capacity)
 293         {
 294           if (__res > __capacity
 295               || __res > size_type(_S_local_capacity))
 296             {
 297               pointer __tmp = _M_create(__res, __capacity);
 298               this->_S_copy(__tmp, _M_data(), length() + 1);
 299               _M_dispose();
 300               _M_data(__tmp);
 301               _M_capacity(__res);
 302             }
 303           else if (!_M_is_local())
 304             {
 305               this->_S_copy(_M_local_data(), _M_data(), length() + 1);
 306               _M_destroy(__capacity);
 307               _M_data(_M_local_data());
 308             }
 309         }
 310     }
 311
 312   template<typename _CharT, typename _Traits, typename _Alloc>
 313     void
 314     basic_string<_CharT, _Traits, _Alloc>::
 315     _M_mutate(size_type __pos, size_type __len1, const _CharT* __s,
 316               size_type __len2)
 317     {
 318       const size_type __how_much = length() - __pos - __len1;
 319
 320       size_type __new_capacity = length() + __len2 - __len1;
 321       pointer __r = _M_create(__new_capacity, capacity());
 322
 323       if (__pos)
 324         this->_S_copy(__r, _M_data(), __pos);
 325       if (__s && __len2)
 326         this->_S_copy(__r + __pos, __s, __len2);
 327       if (__how_much)
 328         this->_S_copy(__r + __pos + __len2,
 329                       _M_data() + __pos + __len1, __how_much);
 330
 331       _M_dispose();
 332       _M_data(__r);
 333       _M_capacity(__new_capacity);
 334     }
 335
 336   template<typename _CharT, typename _Traits, typename _Alloc>
 337     void
 338     basic_string<_CharT, _Traits, _Alloc>::
 339     _M_erase(size_type __pos, size_type __n)
 340     {
 341       const size_type __how_much = length() - __pos - __n;
 342
 343       if (__how_much && __n)
 344         this->_S_move(_M_data() + __pos, _M_data() + __pos + __n, __how_much);
 345
 346       _M_set_length(length() - __n);
 347     }
 348
 349   template<typename _CharT, typename _Traits, typename _Alloc>
 350     void
 351     basic_string<_CharT, _Traits, _Alloc>::
 352     resize(size_type __n, _CharT __c)
 353     {
 354       const size_type __size = this->size();
 355       if (__size < __n)
 356         this->append(__n - __size, __c);
 357       else if (__n < __size)
 358         this->_M_erase(__n, __size - __n);
 359     }
 360
 361   template<typename _CharT, typename _Traits, typename _Alloc>
 362     basic_string<_CharT, _Traits, _Alloc>&
 363     basic_string<_CharT, _Traits, _Alloc>::
 364     _M_append(const _CharT* __s, size_type __n)
 365     {
 366       const size_type __len = __n + this->size();
 367
 368       if (__len <= this->capacity())
 369         {
 370           if (__n)
 371             this->_S_copy(this->_M_data() + this->size(), __s, __n);
 372         }
 373       else
 374         this->_M_mutate(this->size(), size_type(0), __s, __n);
 375
 376       this->_M_set_length(__len);
 377       return *this;
 378     }
 379
 380   template<typename _CharT, typename _Traits, typename _Alloc>
 381     template<typename _InputIterator>
 382       basic_string<_CharT, _Traits, _Alloc>&
 383       basic_string<_CharT, _Traits, _Alloc>::
 384       _M_replace_dispatch(const_iterator __i1, const_iterator __i2,
 385                           _InputIterator __k1, _InputIterator __k2,
 386                           std::__false_type)
 387       {
 388         const basic_string __s(__k1, __k2);
 389         const size_type __n1 = __i2 - __i1;
 390         return _M_replace(__i1 - begin(), __n1, __s._M_data(),
 391                           __s.size());
 392       }
 393
 394   template<typename _CharT, typename _Traits, typename _Alloc>
 395     basic_string<_CharT, _Traits, _Alloc>&
 396     basic_string<_CharT, _Traits, _Alloc>::
 397     _M_replace_aux(size_type __pos1, size_type __n1, size_type __n2,
 398                    _CharT __c)
 399     {
 400       _M_check_length(__n1, __n2, "basic_string::_M_replace_aux");
 401
 402       const size_type __old_size = this->size();
 403       const size_type __new_size = __old_size + __n2 - __n1;
 404
 405       if (__new_size <= this->capacity())
 406         {
 407           _CharT* __p = this->_M_data() + __pos1;
 408
 409           const size_type __how_much = __old_size - __pos1 - __n1;
 410           if (__how_much && __n1 != __n2)
 411             this->_S_move(__p + __n2, __p + __n1, __how_much);
 412         }
 413       else
 414         this->_M_mutate(__pos1, __n1, 0, __n2);
 415
 416       if (__n2)
 417         this->_S_assign(this->_M_data() + __pos1, __n2, __c);
 418
 419       this->_M_set_length(__new_size);
 420       return *this;
 421     }
 422
 423   template<typename _CharT, typename _Traits, typename _Alloc>
 424     basic_string<_CharT, _Traits, _Alloc>&
 425     basic_string<_CharT, _Traits, _Alloc>::
 426     _M_replace(size_type __pos, size_type __len1, const _CharT* __s,
 427                const size_type __len2)
 428     {
 429       _M_check_length(__len1, __len2, "basic_string::_M_replace");
 430
 431       const size_type __old_size = this->size();
 432       const size_type __new_size = __old_size + __len2 - __len1;
 433
 434       if (__new_size <= this->capacity())
 435         {
 436           _CharT* __p = this->_M_data() + __pos;
 437
 438           const size_type __how_much = __old_size - __pos - __len1;
 439           if (_M_disjunct(__s))
 440             {
 441               if (__how_much && __len1 != __len2)
 442                 this->_S_move(__p + __len2, __p + __len1, __how_much);
 443               if (__len2)
 444                 this->_S_copy(__p, __s, __len2);
 445             }
 446           else
 447             {
 448               // Work in-place.
 449               if (__len2 && __len2 <= __len1)
 450                 this->_S_move(__p, __s, __len2);
 451               if (__how_much && __len1 != __len2)
 452                 this->_S_move(__p + __len2, __p + __len1, __how_much);
 453               if (__len2 > __len1)
 454                 {
 455                   if (__s + __len2 <= __p + __len1)
 456                     this->_S_move(__p, __s, __len2);
 457                   else if (__s >= __p + __len1)
 458                     this->_S_copy(__p, __s + __len2 - __len1, __len2);
 459                   else
 460                     {
 461                       const size_type __nleft = (__p + __len1) - __s;
 462                       this->_S_move(__p, __s, __nleft);
 463                       this->_S_copy(__p + __nleft, __p + __len2,
 464                                     __len2 - __nleft);
 465                     }
 466                 }
 467             }
 468         }
 469       else
 470         this->_M_mutate(__pos, __len1, __s, __len2);
 471
 472       this->_M_set_length(__new_size);
 473       return *this;
 474     }
 475
 476   template<typename _CharT, typename _Traits, typename _Alloc>
 477     typename basic_string<_CharT, _Traits, _Alloc>::size_type
 478     basic_string<_CharT, _Traits, _Alloc>::
 479     copy(_CharT* __s, size_type __n, size_type __pos) const
 480     {
 481       _M_check(__pos, "basic_string::copy");
 482       __n = _M_limit(__pos, __n);
 483       __glibcxx_requires_string_len(__s, __n);
 484       if (__n)
 485         _S_copy(__s, _M_data() + __pos, __n);
 486       // 21.3.5.7 par 3: do not append null.  (good.)
 487       return __n;
 488     }
 489
 490 #else  // !_GLIBCXX_USE_CXX11_ABI
 491
 492   template<typename _CharT, typename _Traits, typename _Alloc>
 493     const typename basic_string<_CharT, _Traits, _Alloc>::size_type
 494     basic_string<_CharT, _Traits, _Alloc>::
 495     _Rep::_S_max_size = (((npos - sizeof(_Rep_base))/sizeof(_CharT)) - 1) / 4;
 496
 497   template<typename _CharT, typename _Traits, typename _Alloc>
 498     const _CharT
 499     basic_string<_CharT, _Traits, _Alloc>::
 500     _Rep::_S_terminal = _CharT();
 501
 502   template<typename _CharT, typename _Traits, typename _Alloc>
 503     const typename basic_string<_CharT, _Traits, _Alloc>::size_type
 504     basic_string<_CharT, _Traits, _Alloc>::npos;
 505
 506   // Linker sets _S_empty_rep_storage to all 0s (one reference, empty string)
 507   // at static init time (before static ctors are run).
 508   template<typename _CharT, typename _Traits, typename _Alloc>
 509     typename basic_string<_CharT, _Traits, _Alloc>::size_type
 510     basic_string<_CharT, _Traits, _Alloc>::_Rep::_S_empty_rep_storage[
 511     (sizeof(_Rep_base) + sizeof(_CharT) + sizeof(size_type) - 1) /
 512       sizeof(size_type)];
 513
 514   // NB: This is the special case for Input Iterators, used in
 515   // istreambuf_iterators, etc.
 516   // Input Iterators have a cost structure very different from
 517   // pointers, calling for a different coding style.
 518   template<typename _CharT, typename _Traits, typename _Alloc>
 519     template<typename _InIterator>
 520       _CharT*
 521       basic_string<_CharT, _Traits, _Alloc>::
 522       _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
 523                    input_iterator_tag)
 524       {
 525 #if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
 526         if (__beg == __end && __a == _Alloc())
 527           return _S_empty_rep()._M_refdata();
 528 #endif
 529         // Avoid reallocation for common case.
 530         _CharT __buf[128];
 531         size_type __len = 0;
 532         while (__beg != __end && __len < sizeof(__buf) / sizeof(_CharT))
 533           {
 534             __buf[__len++] = *__beg;
 535             ++__beg;
 536           }
 537         _Rep* __r = _Rep::_S_create(__len, size_type(0), __a);
 538         _M_copy(__r->_M_refdata(), __buf, __len);
 539         __try
 540           {
 541             while (__beg != __end)
 542               {
 543                 if (__len == __r->_M_capacity)
 544                   {
 545                     // Allocate more space.
 546                     _Rep* __another = _Rep::_S_create(__len + 1, __len, __a);
 547                     _M_copy(__another->_M_refdata(), __r->_M_refdata(), __len);
 548                     __r->_M_destroy(__a);
 549                     __r = __another;
 550                   }
 551                 __r->_M_refdata()[__len++] = *__beg;
 552                 ++__beg;
 553               }
 554           }
 555         __catch(...)
 556           {
 557             __r->_M_destroy(__a);
 558             __throw_exception_again;
 559           }
 560         __r->_M_set_length_and_sharable(__len);
 561         return __r->_M_refdata();
 562       }
 563
 564   template<typename _CharT, typename _Traits, typename _Alloc>
 565     template <typename _InIterator>
 566       _CharT*
 567       basic_string<_CharT, _Traits, _Alloc>::
 568       _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
 569                    forward_iterator_tag)
 570       {
 571 #if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
 572         if (__beg == __end && __a == _Alloc())
 573           return _S_empty_rep()._M_refdata();
 574 #endif
 575         // NB: Not required, but considered best practice.
 576         if (__gnu_cxx::__is_null_pointer(__beg) && __beg != __end)
 577           __throw_logic_error(__N("basic_string::_S_construct null not valid"));
 578
 579         const size_type __dnew = static_cast<size_type>(std::distance(__beg,
 580                                                                       __end));
 581         // Check for out_of_range and length_error exceptions.
 582         _Rep* __r = _Rep::_S_create(__dnew, size_type(0), __a);
 583         __try
 584           { _S_copy_chars(__r->_M_refdata(), __beg, __end); }
 585         __catch(...)
 586           {
 587             __r->_M_destroy(__a);
 588             __throw_exception_again;
 589           }
 590         __r->_M_set_length_and_sharable(__dnew);
 591         return __r->_M_refdata();
 592       }
 593
 594   template<typename _CharT, typename _Traits, typename _Alloc>
 595     _CharT*
 596     basic_string<_CharT, _Traits, _Alloc>::
 597     _S_construct(size_type __n, _CharT __c, const _Alloc& __a)
 598     {
 599 #if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
 600       if (__n == 0 && __a == _Alloc())
 601         return _S_empty_rep()._M_refdata();
 602 #endif
 603       // Check for out_of_range and length_error exceptions.
 604       _Rep* __r = _Rep::_S_create(__n, size_type(0), __a);
 605       if (__n)
 606         _M_assign(__r->_M_refdata(), __n, __c);
 607
 608       __r->_M_set_length_and_sharable(__n);
 609       return __r->_M_refdata();
 610     }
 611
 612   template<typename _CharT, typename _Traits, typename _Alloc>
 613     basic_string<_CharT, _Traits, _Alloc>::
 614     basic_string(const basic_string& __str)
 615     : _M_dataplus(__str._M_rep()->_M_grab(_Alloc(__str.get_allocator()),
 616                                           __str.get_allocator()),
 617                   __str.get_allocator())
 618     { }
 619
 620   template<typename _CharT, typename _Traits, typename _Alloc>
 621     basic_string<_CharT, _Traits, _Alloc>::
 622     basic_string(const _Alloc& __a)
 623     : _M_dataplus(_S_construct(size_type(), _CharT(), __a), __a)
 624     { }
 625
 626   template<typename _CharT, typename _Traits, typename _Alloc>
 627     basic_string<_CharT, _Traits, _Alloc>::
 628     basic_string(const basic_string& __str, size_type __pos, size_type __n)
 629     : _M_dataplus(_S_construct(__str._M_data()
 630                                + __str._M_check(__pos,
 631                                                 "basic_string::basic_string"),
 632                                __str._M_data() + __str._M_limit(__pos, __n)
 633                                + __pos, _Alloc()), _Alloc())
 634     { }
 635
 636   template<typename _CharT, typename _Traits, typename _Alloc>
 637     basic_string<_CharT, _Traits, _Alloc>::
 638     basic_string(const basic_string& __str, size_type __pos,
 639                  size_type __n, const _Alloc& __a)
 640     : _M_dataplus(_S_construct(__str._M_data()
 641                                + __str._M_check(__pos,
 642                                                 "basic_string::basic_string"),
 643                                __str._M_data() + __str._M_limit(__pos, __n)
 644                                + __pos, __a), __a)
 645     { }
 646
 647   // TBD: DPG annotate
 648   template<typename _CharT, typename _Traits, typename _Alloc>
 649     basic_string<_CharT, _Traits, _Alloc>::
 650     basic_string(const _CharT* __s, size_type __n, const _Alloc& __a)
 651     : _M_dataplus(_S_construct(__s, __s + __n, __a), __a)
 652     { }
 653
 654   // TBD: DPG annotate
 655   template<typename _CharT, typename _Traits, typename _Alloc>
 656     basic_string<_CharT, _Traits, _Alloc>::
 657     basic_string(const _CharT* __s, const _Alloc& __a)
 658     : _M_dataplus(_S_construct(__s, __s ? __s + traits_type::length(__s) :
 659                                __s + npos, __a), __a)
 660     { }
 661
 662   template<typename _CharT, typename _Traits, typename _Alloc>
 663     basic_string<_CharT, _Traits, _Alloc>::
 664     basic_string(size_type __n, _CharT __c, const _Alloc& __a)
 665     : _M_dataplus(_S_construct(__n, __c, __a), __a)
 666     { }
 667
 668   // TBD: DPG annotate
 669   template<typename _CharT, typename _Traits, typename _Alloc>
 670     template<typename _InputIterator>
 671     basic_string<_CharT, _Traits, _Alloc>::
 672     basic_string(_InputIterator __beg, _InputIterator __end, const _Alloc& __a)
 673     : _M_dataplus(_S_construct(__beg, __end, __a), __a)
 674     { }
 675
 676 #if __cplusplus >= 201103L
 677   template<typename _CharT, typename _Traits, typename _Alloc>
 678     basic_string<_CharT, _Traits, _Alloc>::
 679     basic_string(initializer_list<_CharT> __l, const _Alloc& __a)
 680     : _M_dataplus(_S_construct(__l.begin(), __l.end(), __a), __a)
 681     { }
 682 #endif
 683
 684   template<typename _CharT, typename _Traits, typename _Alloc>
 685     basic_string<_CharT, _Traits, _Alloc>&
 686     basic_string<_CharT, _Traits, _Alloc>::
 687     assign(const basic_string& __str)
 688     {
 689       if (_M_rep() != __str._M_rep())
 690         {
 691           // XXX MT
 692           const allocator_type __a = this->get_allocator();
 693           _CharT* __tmp = __str._M_rep()->_M_grab(__a, __str.get_allocator());
 694           _M_rep()->_M_dispose(__a);
 695           _M_data(__tmp);
 696         }
 697       return *this;
 698     }
 699
 700   template<typename _CharT, typename _Traits, typename _Alloc>
 701     basic_string<_CharT, _Traits, _Alloc>&
 702     basic_string<_CharT, _Traits, _Alloc>::
 703     assign(const _CharT* __s, size_type __n)
 704     {
 705       __glibcxx_requires_string_len(__s, __n);
 706       _M_check_length(this->size(), __n, "basic_string::assign");
 707       if (_M_disjunct(__s) || _M_rep()->_M_is_shared())
 708         return _M_replace_safe(size_type(0), this->size(), __s, __n);
 709       else
 710         {
 711           // Work in-place.
 712           const size_type __pos = __s - _M_data();
 713           if (__pos >= __n)
 714             _M_copy(_M_data(), __s, __n);
 715           else if (__pos)
 716             _M_move(_M_data(), __s, __n);
 717           _M_rep()->_M_set_length_and_sharable(__n);
 718           return *this;
 719         }
 720      }
 721
 722   template<typename _CharT, typename _Traits, typename _Alloc>
 723     basic_string<_CharT, _Traits, _Alloc>&
 724     basic_string<_CharT, _Traits, _Alloc>::
 725     append(size_type __n, _CharT __c)
 726     {
 727       if (__n)
 728         {
 729           _M_check_length(size_type(0), __n, "basic_string::append");
 730           const size_type __len = __n + this->size();
 731           if (__len > this->capacity() || _M_rep()->_M_is_shared())
 732             this->reserve(__len);
 733           _M_assign(_M_data() + this->size(), __n, __c);
 734           _M_rep()->_M_set_length_and_sharable(__len);
 735         }
 736       return *this;
 737     }
 738
 739   template<typename _CharT, typename _Traits, typename _Alloc>
 740     basic_string<_CharT, _Traits, _Alloc>&
 741     basic_string<_CharT, _Traits, _Alloc>::
 742     append(const _CharT* __s, size_type __n)
 743     {
 744       __glibcxx_requires_string_len(__s, __n);
 745       if (__n)
 746         {
 747           _M_check_length(size_type(0), __n, "basic_string::append");
 748           const size_type __len = __n + this->size();
 749           if (__len > this->capacity() || _M_rep()->_M_is_shared())
 750             {
 751               if (_M_disjunct(__s))
 752                 this->reserve(__len);
 753               else
 754                 {
 755                   const size_type __off = __s - _M_data();
 756                   this->reserve(__len);
 757                   __s = _M_data() + __off;
 758                 }
 759             }
 760           _M_copy(_M_data() + this->size(), __s, __n);
 761           _M_rep()->_M_set_length_and_sharable(__len);
 762         }
 763       return *this;
 764     }
 765
 766   template<typename _CharT, typename _Traits, typename _Alloc>
 767     basic_string<_CharT, _Traits, _Alloc>&
 768     basic_string<_CharT, _Traits, _Alloc>::
 769     append(const basic_string& __str)
 770     {
 771       const size_type __size = __str.size();
 772       if (__size)
 773         {
 774           const size_type __len = __size + this->size();
 775           if (__len > this->capacity() || _M_rep()->_M_is_shared())
 776             this->reserve(__len);
 777           _M_copy(_M_data() + this->size(), __str._M_data(), __size);
 778           _M_rep()->_M_set_length_and_sharable(__len);
 779         }
 780       return *this;
 781     }
 782
 783   template<typename _CharT, typename _Traits, typename _Alloc>
 784     basic_string<_CharT, _Traits, _Alloc>&
 785     basic_string<_CharT, _Traits, _Alloc>::
 786     append(const basic_string& __str, size_type __pos, size_type __n)
 787     {
 788       __str._M_check(__pos, "basic_string::append");
 789       __n = __str._M_limit(__pos, __n);
 790       if (__n)
 791         {
 792           const size_type __len = __n + this->size();
 793           if (__len > this->capacity() || _M_rep()->_M_is_shared())
 794             this->reserve(__len);
 795           _M_copy(_M_data() + this->size(), __str._M_data() + __pos, __n);
 796           _M_rep()->_M_set_length_and_sharable(__len);
 797         }
 798       return *this;
 799     }
 800
 801    template<typename _CharT, typename _Traits, typename _Alloc>
 802      basic_string<_CharT, _Traits, _Alloc>&
 803      basic_string<_CharT, _Traits, _Alloc>::
 804      insert(size_type __pos, const _CharT* __s, size_type __n)
 805      {
 806        __glibcxx_requires_string_len(__s, __n);
 807        _M_check(__pos, "basic_string::insert");
 808        _M_check_length(size_type(0), __n, "basic_string::insert");
 809        if (_M_disjunct(__s) || _M_rep()->_M_is_shared())
 810          return _M_replace_safe(__pos, size_type(0), __s, __n);
 811        else
 812          {
 813            // Work in-place.
 814            const size_type __off = __s - _M_data();
 815            _M_mutate(__pos, 0, __n);
 816            __s = _M_data() + __off;
 817            _CharT* __p = _M_data() + __pos;
 818            if (__s  + __n <= __p)
 819              _M_copy(__p, __s, __n);
 820            else if (__s >= __p)
 821              _M_copy(__p, __s + __n, __n);
 822            else
 823              {
 824                const size_type __nleft = __p - __s;
 825                _M_copy(__p, __s, __nleft);
 826                _M_copy(__p + __nleft, __p + __n, __n - __nleft);
 827              }
 828            return *this;
 829          }
 830      }
 831
 832    template<typename _CharT, typename _Traits, typename _Alloc>
 833      typename basic_string<_CharT, _Traits, _Alloc>::iterator
 834      basic_string<_CharT, _Traits, _Alloc>::
 835      erase(iterator __first, iterator __last)
 836      {
 837        _GLIBCXX_DEBUG_PEDASSERT(__first >= _M_ibegin() && __first <= __last
 838                                 && __last <= _M_iend());
 839
 840        // NB: This isn't just an optimization (bail out early when
 841        // there is nothing to do, really), it's also a correctness
 842        // issue vs MT, see libstdc++/40518.
 843        const size_type __size = __last - __first;
 844        if (__size)
 845          {
 846            const size_type __pos = __first - _M_ibegin();
 847            _M_mutate(__pos, __size, size_type(0));
 848            _M_rep()->_M_set_leaked();
 849            return iterator(_M_data() + __pos);
 850          }
 851        else
 852          return __first;
 853      }
 854
 855    template<typename _CharT, typename _Traits, typename _Alloc>
 856      basic_string<_CharT, _Traits, _Alloc>&
 857      basic_string<_CharT, _Traits, _Alloc>::
 858      replace(size_type __pos, size_type __n1, const _CharT* __s,
 859              size_type __n2)
 860      {
 861        __glibcxx_requires_string_len(__s, __n2);
 862        _M_check(__pos, "basic_string::replace");
 863        __n1 = _M_limit(__pos, __n1);
 864        _M_check_length(__n1, __n2, "basic_string::replace");
 865        bool __left;
 866        if (_M_disjunct(__s) || _M_rep()->_M_is_shared())
 867          return _M_replace_safe(__pos, __n1, __s, __n2);
 868        else if ((__left = __s + __n2 <= _M_data() + __pos)
 869                 || _M_data() + __pos + __n1 <= __s)
 870          {
 871            // Work in-place: non-overlapping case.
 872            size_type __off = __s - _M_data();
 873            __left ? __off : (__off += __n2 - __n1);
 874            _M_mutate(__pos, __n1, __n2);
 875            _M_copy(_M_data() + __pos, _M_data() + __off, __n2);
 876            return *this;
 877          }
 878        else
 879          {
 880            // Todo: overlapping case.
 881            const basic_string __tmp(__s, __n2);
 882            return _M_replace_safe(__pos, __n1, __tmp._M_data(), __n2);
 883          }
 884      }
 885
 886   template<typename _CharT, typename _Traits, typename _Alloc>
 887     void
 888     basic_string<_CharT, _Traits, _Alloc>::_Rep::
 889     _M_destroy(const _Alloc& __a) throw ()
 890     {
 891       const size_type __size = sizeof(_Rep_base) +
 892                                (this->_M_capacity + 1) * sizeof(_CharT);
 893       _Raw_bytes_alloc(__a).deallocate(reinterpret_cast<char*>(this), __size);
 894     }
 895
 896   template<typename _CharT, typename _Traits, typename _Alloc>
 897     void
 898     basic_string<_CharT, _Traits, _Alloc>::
 899     _M_leak_hard()
 900     {
 901 #if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
 902       if (_M_rep() == &_S_empty_rep())
 903         return;
 904 #endif
 905       if (_M_rep()->_M_is_shared())
 906         _M_mutate(0, 0, 0);
 907       _M_rep()->_M_set_leaked();
 908     }
 909
 910   template<typename _CharT, typename _Traits, typename _Alloc>
 911     void
 912     basic_string<_CharT, _Traits, _Alloc>::
 913     _M_mutate(size_type __pos, size_type __len1, size_type __len2)
 914     {
 915       const size_type __old_size = this->size();
 916       const size_type __new_size = __old_size + __len2 - __len1;
 917       const size_type __how_much = __old_size - __pos - __len1;
 918
 919       if (__new_size > this->capacity() || _M_rep()->_M_is_shared())
 920         {
 921           // Must reallocate.
 922           const allocator_type __a = get_allocator();
 923           _Rep* __r = _Rep::_S_create(__new_size, this->capacity(), __a);
 924
 925           if (__pos)
 926             _M_copy(__r->_M_refdata(), _M_data(), __pos);
 927           if (__how_much)
 928             _M_copy(__r->_M_refdata() + __pos + __len2,
 929                     _M_data() + __pos + __len1, __how_much);
 930
 931           _M_rep()->_M_dispose(__a);
 932           _M_data(__r->_M_refdata());
 933         }
 934       else if (__how_much && __len1 != __len2)
 935         {
 936           // Work in-place.
 937           _M_move(_M_data() + __pos + __len2,
 938                   _M_data() + __pos + __len1, __how_much);
 939         }
 940       _M_rep()->_M_set_length_and_sharable(__new_size);
 941     }
 942
 943   template<typename _CharT, typename _Traits, typename _Alloc>
 944     void
 945     basic_string<_CharT, _Traits, _Alloc>::
 946     reserve(size_type __res)
 947     {
 948       if (__res != this->capacity() || _M_rep()->_M_is_shared())
 949         {
 950           // Make sure we don't shrink below the current size
 951           if (__res < this->size())
 952             __res = this->size();
 953           const allocator_type __a = get_allocator();
 954           _CharT* __tmp = _M_rep()->_M_clone(__a, __res - this->size());
 955           _M_rep()->_M_dispose(__a);
 956           _M_data(__tmp);
 957         }
 958     }
 959
 960   template<typename _CharT, typename _Traits, typename _Alloc>
 961     void
 962     basic_string<_CharT, _Traits, _Alloc>::
 963     swap(basic_string& __s)
 964     {
 965       if (_M_rep()->_M_is_leaked())
 966         _M_rep()->_M_set_sharable();
 967       if (__s._M_rep()->_M_is_leaked())
 968         __s._M_rep()->_M_set_sharable();
 969       if (this->get_allocator() == __s.get_allocator())
 970         {
 971           _CharT* __tmp = _M_data();
 972           _M_data(__s._M_data());
 973           __s._M_data(__tmp);
 974         }
 975       // The code below can usually be optimized away.
 976       else
 977         {
 978           const basic_string __tmp1(_M_ibegin(), _M_iend(),
 979                                     __s.get_allocator());
 980           const basic_string __tmp2(__s._M_ibegin(), __s._M_iend(),
 981                                     this->get_allocator());
 982           *this = __tmp2;
 983           __s = __tmp1;
 984         }
 985     }
 986
 987   template<typename _CharT, typename _Traits, typename _Alloc>
 988     typename basic_string<_CharT, _Traits, _Alloc>::_Rep*
 989     basic_string<_CharT, _Traits, _Alloc>::_Rep::
 990     _S_create(size_type __capacity, size_type __old_capacity,
 991               const _Alloc& __alloc)
 992     {
 993       // _GLIBCXX_RESOLVE_LIB_DEFECTS
 994       // 83.  String::npos vs. string::max_size()
 995       if (__capacity > _S_max_size)
 996         __throw_length_error(__N("basic_string::_S_create"));
 997
 998       // The standard places no restriction on allocating more memory
 999       // than is strictly needed within this layer at the moment or as
1000       // requested by an explicit application call to reserve().
1001
1002       // Many malloc implementations perform quite poorly when an
1003       // application attempts to allocate memory in a stepwise fashion
1004       // growing each allocation size by only 1 char.  Additionally,
1005       // it makes little sense to allocate less linear memory than the
1006       // natural blocking size of the malloc implementation.
1007       // Unfortunately, we would need a somewhat low-level calculation
1008       // with tuned parameters to get this perfect for any particular
1009       // malloc implementation.  Fortunately, generalizations about
1010       // common features seen among implementations seems to suffice.
1011
1012       // __pagesize need not match the actual VM page size for good
1013       // results in practice, thus we pick a common value on the low
1014       // side.  __malloc_header_size is an estimate of the amount of
1015       // overhead per memory allocation (in practice seen N * sizeof
1016       // (void*) where N is 0, 2 or 4).  According to folklore,
1017       // picking this value on the high side is better than
1018       // low-balling it (especially when this algorithm is used with
1019       // malloc implementations that allocate memory blocks rounded up
1020       // to a size which is a power of 2).
1021       const size_type __pagesize = 4096;
1022       const size_type __malloc_header_size = 4 * sizeof(void*);
1023
1024       // The below implements an exponential growth policy, necessary to
1025       // meet amortized linear time requirements of the library: see
1026       // http://gcc.gnu.org/ml/libstdc++/2001-07/msg00085.html.
1027       // It's active for allocations requiring an amount of memory above
1028       // system pagesize. This is consistent with the requirements of the
1029       // standard: http://gcc.gnu.org/ml/libstdc++/2001-07/msg00130.html
1030       if (__capacity > __old_capacity && __capacity < 2 * __old_capacity)
1031         __capacity = 2 * __old_capacity;
1032
1033       // NB: Need an array of char_type[__capacity], plus a terminating
1034       // null char_type() element, plus enough for the _Rep data structure.
1035       // Whew. Seemingly so needy, yet so elemental.
1036       size_type __size = (__capacity + 1) * sizeof(_CharT) + sizeof(_Rep);
1037
1038       const size_type __adj_size = __size + __malloc_header_size;
1039       if (__adj_size > __pagesize && __capacity > __old_capacity)
1040         {
1041           const size_type __extra = __pagesize - __adj_size % __pagesize;
1042           __capacity += __extra / sizeof(_CharT);
1043           // Never allocate a string bigger than _S_max_size.
1044           if (__capacity > _S_max_size)
1045             __capacity = _S_max_size;
1046           __size = (__capacity + 1) * sizeof(_CharT) + sizeof(_Rep);
1047         }
1048
1049       // NB: Might throw, but no worries about a leak, mate: _Rep()
1050       // does not throw.
1051       void* __place = _Raw_bytes_alloc(__alloc).allocate(__size);
1052       _Rep *__p = new (__place) _Rep;
1053       __p->_M_capacity = __capacity;
1054       // ABI compatibility - 3.4.x set in _S_create both
1055       // _M_refcount and _M_length.  All callers of _S_create
1056       // in basic_string.tcc then set just _M_length.
1057       // In 4.0.x and later both _M_refcount and _M_length
1058       // are initialized in the callers, unfortunately we can
1059       // have 3.4.x compiled code with _S_create callers inlined
1060       // calling 4.0.x+ _S_create.
1061       __p->_M_set_sharable();
1062       return __p;
1063     }
1064
1065   template<typename _CharT, typename _Traits, typename _Alloc>
1066     _CharT*
1067     basic_string<_CharT, _Traits, _Alloc>::_Rep::
1068     _M_clone(const _Alloc& __alloc, size_type __res)
1069     {
1070       // Requested capacity of the clone.
1071       const size_type __requested_cap = this->_M_length + __res;
1072       _Rep* __r = _Rep::_S_create(__requested_cap, this->_M_capacity,
1073                                   __alloc);
1074       if (this->_M_length)
1075         _M_copy(__r->_M_refdata(), _M_refdata(), this->_M_length);
1076
1077       __r->_M_set_length_and_sharable(this->_M_length);
1078       return __r->_M_refdata();
1079     }
1080
1081   template<typename _CharT, typename _Traits, typename _Alloc>
1082     void
1083     basic_string<_CharT, _Traits, _Alloc>::
1084     resize(size_type __n, _CharT __c)
1085     {
1086       const size_type __size = this->size();
1087       _M_check_length(__size, __n, "basic_string::resize");
1088       if (__size < __n)
1089         this->append(__n - __size, __c);
1090       else if (__n < __size)
1091         this->erase(__n);
1092       // else nothing (in particular, avoid calling _M_mutate() unnecessarily.)
1093     }
1094
1095   template<typename _CharT, typename _Traits, typename _Alloc>
1096     template<typename _InputIterator>
1097       basic_string<_CharT, _Traits, _Alloc>&
1098       basic_string<_CharT, _Traits, _Alloc>::
1099       _M_replace_dispatch(iterator __i1, iterator __i2, _InputIterator __k1,
1100                           _InputIterator __k2, __false_type)
1101       {
1102         const basic_string __s(__k1, __k2);
1103         const size_type __n1 = __i2 - __i1;
1104         _M_check_length(__n1, __s.size(), "basic_string::_M_replace_dispatch");
1105         return _M_replace_safe(__i1 - _M_ibegin(), __n1, __s._M_data(),
1106                                __s.size());
1107       }
1108
1109   template<typename _CharT, typename _Traits, typename _Alloc>
1110     basic_string<_CharT, _Traits, _Alloc>&
1111     basic_string<_CharT, _Traits, _Alloc>::
1112     _M_replace_aux(size_type __pos1, size_type __n1, size_type __n2,
1113                    _CharT __c)
1114     {
1115       _M_check_length(__n1, __n2, "basic_string::_M_replace_aux");
1116       _M_mutate(__pos1, __n1, __n2);
1117       if (__n2)
1118         _M_assign(_M_data() + __pos1, __n2, __c);
1119       return *this;
1120     }
1121
1122   template<typename _CharT, typename _Traits, typename _Alloc>
1123     basic_string<_CharT, _Traits, _Alloc>&
1124     basic_string<_CharT, _Traits, _Alloc>::
1125     _M_replace_safe(size_type __pos1, size_type __n1, const _CharT* __s,
1126                     size_type __n2)
1127     {
1128       _M_mutate(__pos1, __n1, __n2);
1129       if (__n2)
1130         _M_copy(_M_data() + __pos1, __s, __n2);
1131       return *this;
1132     }
1133
1134     template<typename _CharT, typename _Traits, typename _Alloc>
1135     typename basic_string<_CharT, _Traits, _Alloc>::size_type
1136     basic_string<_CharT, _Traits, _Alloc>::
1137     copy(_CharT* __s, size_type __n, size_type __pos) const
1138     {
1139       _M_check(__pos, "basic_string::copy");
1140       __n = _M_limit(__pos, __n);
1141       __glibcxx_requires_string_len(__s, __n);
1142       if (__n)
1143         _M_copy(__s, _M_data() + __pos, __n);
1144       // 21.3.5.7 par 3: do not append null.  (good.)
1145       return __n;
1146     }
1147 #endif  // !_GLIBCXX_USE_CXX11_ABI
1148
1149   template<typename _CharT, typename _Traits, typename _Alloc>
1150     basic_string<_CharT, _Traits, _Alloc>
1151     operator+(const _CharT* __lhs,
1152               const basic_string<_CharT, _Traits, _Alloc>& __rhs)
1153     {
1154       __glibcxx_requires_string(__lhs);
1155       typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
1156       typedef typename __string_type::size_type   __size_type;
1157       const __size_type __len = _Traits::length(__lhs);
1158       __string_type __str;
1159       __str.reserve(__len + __rhs.size());
1160       __str.append(__lhs, __len);
1161       __str.append(__rhs);
1162       return __str;
1163     }
1164
1165   template<typename _CharT, typename _Traits, typename _Alloc>
1166     basic_string<_CharT, _Traits, _Alloc>
1167     operator+(_CharT __lhs, const basic_string<_CharT, _Traits, _Alloc>& __rhs)
1168     {
1169       typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
1170       typedef typename __string_type::size_type   __size_type;
1171       __string_type __str;
1172       const __size_type __len = __rhs.size();
1173       __str.reserve(__len + 1);
1174       __str.append(__size_type(1), __lhs);
1175       __str.append(__rhs);
1176       return __str;
1177     }
1178
1179   template<typename _CharT, typename _Traits, typename _Alloc>
1180     typename basic_string<_CharT, _Traits, _Alloc>::size_type
1181     basic_string<_CharT, _Traits, _Alloc>::
1182     find(const _CharT* __s, size_type __pos, size_type __n) const
1183     {
1184       __glibcxx_requires_string_len(__s, __n);
1185       const size_type __size = this->size();
1186       const _CharT* __data = _M_data();
1187
1188       if (__n == 0)
1189         return __pos <= __size ? __pos : npos;
1190
1191       if (__n <= __size)
1192         {
1193           for (; __pos <= __size - __n; ++__pos)
1194             if (traits_type::eq(__data[__pos], __s[0])
1195                 && traits_type::compare(__data + __pos + 1,
1196                                         __s + 1, __n - 1) == 0)
1197               return __pos;
1198         }
1199       return npos;
1200     }
1201
1202   template<typename _CharT, typename _Traits, typename _Alloc>
1203     typename basic_string<_CharT, _Traits, _Alloc>::size_type
1204     basic_string<_CharT, _Traits, _Alloc>::
1205     find(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
1206     {
1207       size_type __ret = npos;
1208       const size_type __size = this->size();
1209       if (__pos < __size)
1210         {
1211           const _CharT* __data = _M_data();
1212           const size_type __n = __size - __pos;
1213           const _CharT* __p = traits_type::find(__data + __pos, __n, __c);
1214           if (__p)
1215             __ret = __p - __data;
1216         }
1217       return __ret;
1218     }
1219
1220   template<typename _CharT, typename _Traits, typename _Alloc>
1221     typename basic_string<_CharT, _Traits, _Alloc>::size_type
1222     basic_string<_CharT, _Traits, _Alloc>::
1223     rfind(const _CharT* __s, size_type __pos, size_type __n) const
1224     {
1225       __glibcxx_requires_string_len(__s, __n);
1226       const size_type __size = this->size();
1227       if (__n <= __size)
1228         {
1229           __pos = std::min(size_type(__size - __n), __pos);
1230           const _CharT* __data = _M_data();
1231           do
1232             {
1233               if (traits_type::compare(__data + __pos, __s, __n) == 0)
1234                 return __pos;
1235             }
1236           while (__pos-- > 0);
1237         }
1238       return npos;
1239     }
1240
1241   template<typename _CharT, typename _Traits, typename _Alloc>
1242     typename basic_string<_CharT, _Traits, _Alloc>::size_type
1243     basic_string<_CharT, _Traits, _Alloc>::
1244     rfind(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
1245     {
1246       size_type __size = this->size();
1247       if (__size)
1248         {
1249           if (--__size > __pos)
1250             __size = __pos;
1251           for (++__size; __size-- > 0; )
1252             if (traits_type::eq(_M_data()[__size], __c))
1253               return __size;
1254         }
1255       return npos;
1256     }
1257
1258   template<typename _CharT, typename _Traits, typename _Alloc>
1259     typename basic_string<_CharT, _Traits, _Alloc>::size_type
1260     basic_string<_CharT, _Traits, _Alloc>::
1261     find_first_of(const _CharT* __s, size_type __pos, size_type __n) const
1262     {
1263       __glibcxx_requires_string_len(__s, __n);
1264       for (; __n && __pos < this->size(); ++__pos)
1265         {
1266           const _CharT* __p = traits_type::find(__s, __n, _M_data()[__pos]);
1267           if (__p)
1268             return __pos;
1269         }
1270       return npos;
1271     }
1272
1273   template<typename _CharT, typename _Traits, typename _Alloc>
1274     typename basic_string<_CharT, _Traits, _Alloc>::size_type
1275     basic_string<_CharT, _Traits, _Alloc>::
1276     find_last_of(const _CharT* __s, size_type __pos, size_type __n) const
1277     {
1278       __glibcxx_requires_string_len(__s, __n);
1279       size_type __size = this->size();
1280       if (__size && __n)
1281         {
1282           if (--__size > __pos)
1283             __size = __pos;
1284           do
1285             {
1286               if (traits_type::find(__s, __n, _M_data()[__size]))
1287                 return __size;
1288             }
1289           while (__size-- != 0);
1290         }
1291       return npos;
1292     }
1293
1294   template<typename _CharT, typename _Traits, typename _Alloc>
1295     typename basic_string<_CharT, _Traits, _Alloc>::size_type
1296     basic_string<_CharT, _Traits, _Alloc>::
1297     find_first_not_of(const _CharT* __s, size_type __pos, size_type __n) const
1298     {
1299       __glibcxx_requires_string_len(__s, __n);
1300       for (; __pos < this->size(); ++__pos)
1301         if (!traits_type::find(__s, __n, _M_data()[__pos]))
1302           return __pos;
1303       return npos;
1304     }
1305
1306   template<typename _CharT, typename _Traits, typename _Alloc>
1307     typename basic_string<_CharT, _Traits, _Alloc>::size_type
1308     basic_string<_CharT, _Traits, _Alloc>::
1309     find_first_not_of(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
1310     {
1311       for (; __pos < this->size(); ++__pos)
1312         if (!traits_type::eq(_M_data()[__pos], __c))
1313           return __pos;
1314       return npos;
1315     }
1316
1317   template<typename _CharT, typename _Traits, typename _Alloc>
1318     typename basic_string<_CharT, _Traits, _Alloc>::size_type
1319     basic_string<_CharT, _Traits, _Alloc>::
1320     find_last_not_of(const _CharT* __s, size_type __pos, size_type __n) const
1321     {
1322       __glibcxx_requires_string_len(__s, __n);
1323       size_type __size = this->size();
1324       if (__size)
1325         {
1326           if (--__size > __pos)
1327             __size = __pos;
1328           do
1329             {
1330               if (!traits_type::find(__s, __n, _M_data()[__size]))
1331                 return __size;
1332             }
1333           while (__size--);
1334         }
1335       return npos;
1336     }
1337
1338   template<typename _CharT, typename _Traits, typename _Alloc>
1339     typename basic_string<_CharT, _Traits, _Alloc>::size_type
1340     basic_string<_CharT, _Traits, _Alloc>::
1341     find_last_not_of(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
1342     {
1343       size_type __size = this->size();
1344       if (__size)
1345         {
1346           if (--__size > __pos)
1347             __size = __pos;
1348           do
1349             {
1350               if (!traits_type::eq(_M_data()[__size], __c))
1351                 return __size;
1352             }
1353           while (__size--);
1354         }
1355       return npos;
1356     }
1357
1358   template<typename _CharT, typename _Traits, typename _Alloc>
1359     int
1360     basic_string<_CharT, _Traits, _Alloc>::
1361     compare(size_type __pos, size_type __n, const basic_string& __str) const
1362     {
1363       _M_check(__pos, "basic_string::compare");
1364       __n = _M_limit(__pos, __n);
1365       const size_type __osize = __str.size();
1366       const size_type __len = std::min(__n, __osize);
1367       int __r = traits_type::compare(_M_data() + __pos, __str.data(), __len);
1368       if (!__r)
1369         __r = _S_compare(__n, __osize);
1370       return __r;
1371     }
1372
1373   template<typename _CharT, typename _Traits, typename _Alloc>
1374     int
1375     basic_string<_CharT, _Traits, _Alloc>::
1376     compare(size_type __pos1, size_type __n1, const basic_string& __str,
1377             size_type __pos2, size_type __n2) const
1378     {
1379       _M_check(__pos1, "basic_string::compare");
1380       __str._M_check(__pos2, "basic_string::compare");
1381       __n1 = _M_limit(__pos1, __n1);
1382       __n2 = __str._M_limit(__pos2, __n2);
1383       const size_type __len = std::min(__n1, __n2);
1384       int __r = traits_type::compare(_M_data() + __pos1,
1385                                      __str.data() + __pos2, __len);
1386       if (!__r)
1387         __r = _S_compare(__n1, __n2);
1388       return __r;
1389     }
1390
1391   template<typename _CharT, typename _Traits, typename _Alloc>
1392     int
1393     basic_string<_CharT, _Traits, _Alloc>::
1394     compare(const _CharT* __s) const
1395     {
1396       __glibcxx_requires_string(__s);
1397       const size_type __size = this->size();
1398       const size_type __osize = traits_type::length(__s);
1399       const size_type __len = std::min(__size, __osize);
1400       int __r = traits_type::compare(_M_data(), __s, __len);
1401       if (!__r)
1402         __r = _S_compare(__size, __osize);
1403       return __r;
1404     }
1405
1406   template<typename _CharT, typename _Traits, typename _Alloc>
1407     int
1408     basic_string <_CharT, _Traits, _Alloc>::
1409     compare(size_type __pos, size_type __n1, const _CharT* __s) const
1410     {
1411       __glibcxx_requires_string(__s);
1412       _M_check(__pos, "basic_string::compare");
1413       __n1 = _M_limit(__pos, __n1);
1414       const size_type __osize = traits_type::length(__s);
1415       const size_type __len = std::min(__n1, __osize);
1416       int __r = traits_type::compare(_M_data() + __pos, __s, __len);
1417       if (!__r)
1418         __r = _S_compare(__n1, __osize);
1419       return __r;
1420     }
1421
1422   template<typename _CharT, typename _Traits, typename _Alloc>
1423     int
1424     basic_string <_CharT, _Traits, _Alloc>::
1425     compare(size_type __pos, size_type __n1, const _CharT* __s,
1426             size_type __n2) const
1427     {
1428       __glibcxx_requires_string_len(__s, __n2);
1429       _M_check(__pos, "basic_string::compare");
1430       __n1 = _M_limit(__pos, __n1);
1431       const size_type __len = std::min(__n1, __n2);
1432       int __r = traits_type::compare(_M_data() + __pos, __s, __len);
1433       if (!__r)
1434         __r = _S_compare(__n1, __n2);
1435       return __r;
1436     }
1437
1438   // 21.3.7.9 basic_string::getline and operators
1439   template<typename _CharT, typename _Traits, typename _Alloc>
1440     basic_istream<_CharT, _Traits>&
1441     operator>>(basic_istream<_CharT, _Traits>& __in,
1442                basic_string<_CharT, _Traits, _Alloc>& __str)
1443     {
1444       typedef basic_istream<_CharT, _Traits>            __istream_type;
1445       typedef basic_string<_CharT, _Traits, _Alloc>     __string_type;
1446       typedef typename __istream_type::ios_base         __ios_base;
1447       typedef typename __istream_type::int_type         __int_type;
1448       typedef typename __string_type::size_type         __size_type;
1449       typedef ctype<_CharT>                             __ctype_type;
1450       typedef typename __ctype_type::ctype_base         __ctype_base;
1451
1452       __size_type __extracted = 0;
1453       typename __ios_base::iostate __err = __ios_base::goodbit;
1454       typename __istream_type::sentry __cerb(__in, false);
1455       if (__cerb)
1456         {
1457           __try
1458             {
1459               // Avoid reallocation for common case.
1460               __str.erase();
1461               _CharT __buf[128];
1462               __size_type __len = 0;
1463               const streamsize __w = __in.width();
1464               const __size_type __n = __w > 0 ? static_cast<__size_type>(__w)
1465                                               : __str.max_size();
1466               const __ctype_type& __ct = use_facet<__ctype_type>(__in.getloc());
1467               const __int_type __eof = _Traits::eof();
1468               __int_type __c = __in.rdbuf()->sgetc();
1469
1470               while (__extracted < __n
1471                      && !_Traits::eq_int_type(__c, __eof)
1472                      && !__ct.is(__ctype_base::space,
1473                                  _Traits::to_char_type(__c)))
1474                 {
1475                   if (__len == sizeof(__buf) / sizeof(_CharT))
1476                     {
1477                       __str.append(__buf, sizeof(__buf) / sizeof(_CharT));
1478                       __len = 0;
1479                     }
1480                   __buf[__len++] = _Traits::to_char_type(__c);
1481                   ++__extracted;
1482                   __c = __in.rdbuf()->snextc();
1483                 }
1484               __str.append(__buf, __len);
1485
1486               if (_Traits::eq_int_type(__c, __eof))
1487                 __err |= __ios_base::eofbit;
1488               __in.width(0);
1489             }
1490           __catch(__cxxabiv1::__forced_unwind&)
1491             {
1492               __in._M_setstate(__ios_base::badbit);
1493               __throw_exception_again;
1494             }
1495           __catch(...)
1496             {
1497               // _GLIBCXX_RESOLVE_LIB_DEFECTS
1498               // 91. Description of operator>> and getline() for string<>
1499               // might cause endless loop
1500               __in._M_setstate(__ios_base::badbit);
1501             }
1502         }
1503       // 211.  operator>>(istream&, string&) doesn't set failbit
1504       if (!__extracted)
1505         __err |= __ios_base::failbit;
1506       if (__err)
1507         __in.setstate(__err);
1508       return __in;
1509     }
1510
1511   template<typename _CharT, typename _Traits, typename _Alloc>
1512     basic_istream<_CharT, _Traits>&
1513     getline(basic_istream<_CharT, _Traits>& __in,
1514             basic_string<_CharT, _Traits, _Alloc>& __str, _CharT __delim)
1515     {
1516       typedef basic_istream<_CharT, _Traits>            __istream_type;
1517       typedef basic_string<_CharT, _Traits, _Alloc>     __string_type;
1518       typedef typename __istream_type::ios_base         __ios_base;
1519       typedef typename __istream_type::int_type         __int_type;
1520       typedef typename __string_type::size_type         __size_type;
1521
1522       __size_type __extracted = 0;
1523       const __size_type __n = __str.max_size();
1524       typename __ios_base::iostate __err = __ios_base::goodbit;
1525       typename __istream_type::sentry __cerb(__in, true);
1526       if (__cerb)
1527         {
1528           __try
1529             {
1530               __str.erase();
1531               const __int_type __idelim = _Traits::to_int_type(__delim);
1532               const __int_type __eof = _Traits::eof();
1533               __int_type __c = __in.rdbuf()->sgetc();
1534
1535               while (__extracted < __n
1536                      && !_Traits::eq_int_type(__c, __eof)
1537                      && !_Traits::eq_int_type(__c, __idelim))
1538                 {
1539                   __str += _Traits::to_char_type(__c);
1540                   ++__extracted;
1541                   __c = __in.rdbuf()->snextc();
1542                 }
1543
1544               if (_Traits::eq_int_type(__c, __eof))
1545                 __err |= __ios_base::eofbit;
1546               else if (_Traits::eq_int_type(__c, __idelim))
1547                 {
1548                   ++__extracted;
1549                   __in.rdbuf()->sbumpc();
1550                 }
1551               else
1552                 __err |= __ios_base::failbit;
1553             }
1554           __catch(__cxxabiv1::__forced_unwind&)
1555             {
1556               __in._M_setstate(__ios_base::badbit);
1557               __throw_exception_again;
1558             }
1559           __catch(...)
1560             {
1561               // _GLIBCXX_RESOLVE_LIB_DEFECTS
1562               // 91. Description of operator>> and getline() for string<>
1563               // might cause endless loop
1564               __in._M_setstate(__ios_base::badbit);
1565             }
1566         }
1567       if (!__extracted)
1568         __err |= __ios_base::failbit;
1569       if (__err)
1570         __in.setstate(__err);
1571       return __in;
1572     }
1573
1574   // Inhibit implicit instantiations for required instantiations,
1575   // which are defined via explicit instantiations elsewhere.
1576 #if _GLIBCXX_EXTERN_TEMPLATE > 0
1577   extern template class basic_string<char>;
1578   extern template
1579     basic_istream<char>&
1580     operator>>(basic_istream<char>&, string&);
1581   extern template
1582     basic_ostream<char>&
1583     operator<<(basic_ostream<char>&, const string&);
1584   extern template
1585     basic_istream<char>&
1586     getline(basic_istream<char>&, string&, char);
1587   extern template
1588     basic_istream<char>&
1589     getline(basic_istream<char>&, string&);
1590
1591 #ifdef _GLIBCXX_USE_WCHAR_T
1592   extern template class basic_string<wchar_t>;
1593   extern template
1594     basic_istream<wchar_t>&
1595     operator>>(basic_istream<wchar_t>&, wstring&);
1596   extern template
1597     basic_ostream<wchar_t>&
1598     operator<<(basic_ostream<wchar_t>&, const wstring&);
1599   extern template
1600     basic_istream<wchar_t>&
1601     getline(basic_istream<wchar_t>&, wstring&, wchar_t);
1602   extern template
1603     basic_istream<wchar_t>&
1604     getline(basic_istream<wchar_t>&, wstring&);
1605 #endif
1606 #endif
1607
1608 _GLIBCXX_END_NAMESPACE_VERSION
1609 } // namespace std
1610
1611 #endif