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

   1 // istream classes -*- C++ -*-
   2
   3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004
   4 // Free Software Foundation, Inc.
   5 //
   6 // This file is part of the GNU ISO C++ Library.  This library is free
   7 // software; you can redistribute it and/or modify it under the
   8 // terms of the GNU General Public License as published by the
   9 // Free Software Foundation; either version 2, or (at your option)
  10 // any later version.
  11
  12 // This library is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16
  17 // You should have received a copy of the GNU General Public License along
  18 // with this library; see the file COPYING.  If not, write to the Free
  19 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  20 // USA.
  21
  22 // As a special exception, you may use this file as part of a free software
  23 // library without restriction.  Specifically, if other files instantiate
  24 // templates or use macros or inline functions from this file, or you compile
  25 // this file and link it with other files to produce an executable, this
  26 // file does not by itself cause the resulting executable to be covered by
  27 // the GNU General Public License.  This exception does not however
  28 // invalidate any other reasons why the executable file might be covered by
  29 // the GNU General Public License.
  30
  31 //
  32 // ISO C++ 14882: 27.6.1  Input streams
  33 //
  34
  35 #ifndef _ISTREAM_TCC
  36 #define _ISTREAM_TCC 1
  37
  38 #pragma GCC system_header
  39
  40 #include <locale>
  41 #include <ostream> // For flush()
  42
  43 namespace std
  44 {
  45   template<typename _CharT, typename _Traits>
  46     basic_istream<_CharT, _Traits>::sentry::
  47     sentry(basic_istream<_CharT, _Traits>& __in, bool __noskip) : _M_ok(false)
  48     {
  49       ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
  50       if (__in.good())
  51         {
  52           if (__in.tie())
  53             __in.tie()->flush();
  54           if (!__noskip && (__in.flags() & ios_base::skipws))
  55             {
  56               const __int_type __eof = traits_type::eof();
  57               __streambuf_type* __sb = __in.rdbuf();
  58               __int_type __c = __sb->sgetc();
  59
  60               const __ctype_type& __ct = __check_facet(__in._M_ctype);
  61               while (!traits_type::eq_int_type(__c, __eof)
  62                      && __ct.is(ctype_base::space,
  63                                 traits_type::to_char_type(__c)))
  64                 __c = __sb->snextc();
  65
  66               // _GLIBCXX_RESOLVE_LIB_DEFECTS
  67               // 195. Should basic_istream::sentry's constructor ever
  68               // set eofbit?
  69               if (traits_type::eq_int_type(__c, __eof))
  70                 __err |= ios_base::eofbit;
  71             }
  72         }
  73
  74       if (__in.good() && __err == ios_base::goodbit)
  75         _M_ok = true;
  76       else
  77         {
  78           __err |= ios_base::failbit;
  79           __in.setstate(__err);
  80         }
  81     }
  82
  83   template<typename _CharT, typename _Traits>
  84     basic_istream<_CharT, _Traits>&
  85     basic_istream<_CharT, _Traits>::
  86     operator>>(__istream_type& (*__pf)(__istream_type&))
  87     { return __pf(*this); }
  88
  89   template<typename _CharT, typename _Traits>
  90     basic_istream<_CharT, _Traits>&
  91     basic_istream<_CharT, _Traits>::
  92     operator>>(__ios_type& (*__pf)(__ios_type&))
  93     {
  94       __pf(*this);
  95       return *this;
  96     }
  97
  98   template<typename _CharT, typename _Traits>
  99     basic_istream<_CharT, _Traits>&
 100     basic_istream<_CharT, _Traits>::
 101     operator>>(ios_base& (*__pf)(ios_base&))
 102     {
 103       __pf(*this);
 104       return *this;
 105     }
 106
 107   template<typename _CharT, typename _Traits>
 108     basic_istream<_CharT, _Traits>&
 109     basic_istream<_CharT, _Traits>::
 110     operator>>(bool& __n)
 111     {
 112       sentry __cerb(*this, false);
 113       if (__cerb)
 114         {
 115           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 116           try
 117             {
 118               const __num_get_type& __ng = __check_facet(this->_M_num_get);
 119               __ng.get(*this, 0, *this, __err, __n);
 120             }
 121           catch(...)
 122             { this->_M_setstate(ios_base::badbit); }
 123           if (__err)
 124             this->setstate(__err);
 125         }
 126       return *this;
 127     }
 128
 129   template<typename _CharT, typename _Traits>
 130     basic_istream<_CharT, _Traits>&
 131     basic_istream<_CharT, _Traits>::
 132     operator>>(short& __n)
 133     {
 134       sentry __cerb(*this, false);
 135       if (__cerb)
 136         {
 137           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 138           try
 139             {
 140               long __l;
 141               const __num_get_type& __ng = __check_facet(this->_M_num_get);
 142               __ng.get(*this, 0, *this, __err, __l);
 143               // _GLIBCXX_RESOLVE_LIB_DEFECTS
 144               // 118. basic_istream uses nonexistent num_get member functions.
 145               if (!(__err & ios_base::failbit)
 146                   && (numeric_limits<short>::min() <= __l
 147                       && __l <= numeric_limits<short>::max()))
 148                 __n = __l;
 149               else
 150                 __err |= ios_base::failbit;
 151             }
 152           catch(...)
 153             { this->_M_setstate(ios_base::badbit); }
 154           if (__err)
 155             this->setstate(__err);
 156         }
 157       return *this;
 158     }
 159
 160   template<typename _CharT, typename _Traits>
 161     basic_istream<_CharT, _Traits>&
 162     basic_istream<_CharT, _Traits>::
 163     operator>>(unsigned short& __n)
 164     {
 165       sentry __cerb(*this, false);
 166       if (__cerb)
 167         {
 168           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 169           try
 170             {
 171               const __num_get_type& __ng = __check_facet(this->_M_num_get);
 172               __ng.get(*this, 0, *this, __err, __n);
 173             }
 174           catch(...)
 175             { this->_M_setstate(ios_base::badbit); }
 176           if (__err)
 177             this->setstate(__err);
 178         }
 179       return *this;
 180     }
 181
 182   template<typename _CharT, typename _Traits>
 183     basic_istream<_CharT, _Traits>&
 184     basic_istream<_CharT, _Traits>::
 185     operator>>(int& __n)
 186     {
 187       sentry __cerb(*this, false);
 188       if (__cerb)
 189         {
 190           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 191           try
 192             {
 193               long __l;
 194               const __num_get_type& __ng = __check_facet(this->_M_num_get);
 195               __ng.get(*this, 0, *this, __err, __l);
 196               // _GLIBCXX_RESOLVE_LIB_DEFECTS
 197               // 118. basic_istream uses nonexistent num_get member functions.
 198               if (!(__err & ios_base::failbit)
 199                   && (numeric_limits<int>::min() <= __l
 200                       && __l <= numeric_limits<int>::max()))
 201                 __n = __l;
 202               else
 203                 __err |= ios_base::failbit;
 204             }
 205           catch(...)
 206             { this->_M_setstate(ios_base::badbit); }
 207           if (__err)
 208             this->setstate(__err);
 209         }
 210       return *this;
 211     }
 212
 213   template<typename _CharT, typename _Traits>
 214     basic_istream<_CharT, _Traits>&
 215     basic_istream<_CharT, _Traits>::
 216     operator>>(unsigned int& __n)
 217     {
 218       sentry __cerb(*this, false);
 219       if (__cerb)
 220         {
 221           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 222           try
 223             {
 224               const __num_get_type& __ng = __check_facet(this->_M_num_get);
 225               __ng.get(*this, 0, *this, __err, __n);
 226             }
 227           catch(...)
 228             { this->_M_setstate(ios_base::badbit); }
 229           if (__err)
 230             this->setstate(__err);
 231         }
 232       return *this;
 233     }
 234
 235   template<typename _CharT, typename _Traits>
 236     basic_istream<_CharT, _Traits>&
 237     basic_istream<_CharT, _Traits>::
 238     operator>>(long& __n)
 239     {
 240       sentry __cerb(*this, false);
 241       if (__cerb)
 242         {
 243           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 244           try
 245             {
 246               const __num_get_type& __ng = __check_facet(this->_M_num_get);
 247               __ng.get(*this, 0, *this, __err, __n);
 248             }
 249           catch(...)
 250             { this->_M_setstate(ios_base::badbit); }
 251           if (__err)
 252             this->setstate(__err);
 253         }
 254       return *this;
 255     }
 256
 257   template<typename _CharT, typename _Traits>
 258     basic_istream<_CharT, _Traits>&
 259     basic_istream<_CharT, _Traits>::
 260     operator>>(unsigned long& __n)
 261     {
 262       sentry __cerb(*this, false);
 263       if (__cerb)
 264         {
 265           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 266           try
 267             {
 268               const __num_get_type& __ng = __check_facet(this->_M_num_get);
 269               __ng.get(*this, 0, *this, __err, __n);
 270             }
 271           catch(...)
 272             { this->_M_setstate(ios_base::badbit); }
 273           if (__err)
 274             this->setstate(__err);
 275         }
 276       return *this;
 277     }
 278
 279 #ifdef _GLIBCXX_USE_LONG_LONG
 280   template<typename _CharT, typename _Traits>
 281     basic_istream<_CharT, _Traits>&
 282     basic_istream<_CharT, _Traits>::
 283     operator>>(long long& __n)
 284     {
 285       sentry __cerb(*this, false);
 286       if (__cerb)
 287         {
 288           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 289           try
 290             {
 291               const __num_get_type& __ng = __check_facet(this->_M_num_get);
 292               __ng.get(*this, 0, *this, __err, __n);
 293             }
 294           catch(...)
 295             { this->_M_setstate(ios_base::badbit); }
 296           if (__err)
 297             this->setstate(__err);
 298         }
 299       return *this;
 300     }
 301
 302   template<typename _CharT, typename _Traits>
 303     basic_istream<_CharT, _Traits>&
 304     basic_istream<_CharT, _Traits>::
 305     operator>>(unsigned long long& __n)
 306     {
 307       sentry __cerb(*this, false);
 308       if (__cerb)
 309         {
 310           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 311           try
 312             {
 313               const __num_get_type& __ng = __check_facet(this->_M_num_get);
 314               __ng.get(*this, 0, *this, __err, __n);
 315             }
 316           catch(...)
 317             { this->_M_setstate(ios_base::badbit); }
 318           if (__err)
 319             this->setstate(__err);
 320         }
 321       return *this;
 322     }
 323 #endif
 324
 325   template<typename _CharT, typename _Traits>
 326     basic_istream<_CharT, _Traits>&
 327     basic_istream<_CharT, _Traits>::
 328     operator>>(float& __n)
 329     {
 330       sentry __cerb(*this, false);
 331       if (__cerb)
 332         {
 333           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 334           try
 335             {
 336               const __num_get_type& __ng = __check_facet(this->_M_num_get);
 337               __ng.get(*this, 0, *this, __err, __n);
 338             }
 339           catch(...)
 340             { this->_M_setstate(ios_base::badbit); }
 341           if (__err)
 342             this->setstate(__err);
 343         }
 344       return *this;
 345     }
 346
 347   template<typename _CharT, typename _Traits>
 348     basic_istream<_CharT, _Traits>&
 349     basic_istream<_CharT, _Traits>::
 350     operator>>(double& __n)
 351     {
 352       sentry __cerb(*this, false);
 353       if (__cerb)
 354         {
 355           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 356           try
 357             {
 358               const __num_get_type& __ng = __check_facet(this->_M_num_get);
 359               __ng.get(*this, 0, *this, __err, __n);
 360             }
 361           catch(...)
 362             { this->_M_setstate(ios_base::badbit); }
 363           if (__err)
 364             this->setstate(__err);
 365         }
 366       return *this;
 367     }
 368
 369   template<typename _CharT, typename _Traits>
 370     basic_istream<_CharT, _Traits>&
 371     basic_istream<_CharT, _Traits>::
 372     operator>>(long double& __n)
 373     {
 374       sentry __cerb(*this, false);
 375       if (__cerb)
 376         {
 377           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 378           try
 379             {
 380               const __num_get_type& __ng = __check_facet(this->_M_num_get);
 381               __ng.get(*this, 0, *this, __err, __n);
 382             }
 383           catch(...)
 384             { this->_M_setstate(ios_base::badbit); }
 385           if (__err)
 386             this->setstate(__err);
 387         }
 388       return *this;
 389     }
 390
 391   template<typename _CharT, typename _Traits>
 392     basic_istream<_CharT, _Traits>&
 393     basic_istream<_CharT, _Traits>::
 394     operator>>(void*& __n)
 395     {
 396       sentry __cerb(*this, false);
 397       if (__cerb)
 398         {
 399           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 400           try
 401             {
 402               const __num_get_type& __ng = __check_facet(this->_M_num_get);
 403               __ng.get(*this, 0, *this, __err, __n);
 404             }
 405           catch(...)
 406             { this->_M_setstate(ios_base::badbit); }
 407           if (__err)
 408             this->setstate(__err);
 409         }
 410       return *this;
 411     }
 412
 413   template<typename _CharT, typename _Traits>
 414     basic_istream<_CharT, _Traits>&
 415     basic_istream<_CharT, _Traits>::
 416     operator>>(__streambuf_type* __sbout)
 417     {
 418       ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 419       sentry __cerb(*this, false);
 420       if (__cerb && __sbout)
 421         {
 422           try
 423             {
 424               if (!__copy_streambufs(this->rdbuf(), __sbout))
 425                 __err |= ios_base::failbit;
 426             }
 427           catch(...)
 428             { this->_M_setstate(ios_base::failbit); }
 429         }
 430       else if (!__sbout)
 431         __err |= ios_base::failbit;
 432       if (__err)
 433         this->setstate(__err);
 434       return *this;
 435     }
 436
 437   template<typename _CharT, typename _Traits>
 438     typename basic_istream<_CharT, _Traits>::int_type
 439     basic_istream<_CharT, _Traits>::
 440     get(void)
 441     {
 442       const int_type __eof = traits_type::eof();
 443       int_type __c = __eof;
 444       _M_gcount = 0;
 445       ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 446       sentry __cerb(*this, true);
 447       if (__cerb)
 448         {
 449           try
 450             {
 451               __c = this->rdbuf()->sbumpc();
 452               // 27.6.1.1 paragraph 3
 453               if (!traits_type::eq_int_type(__c, __eof))
 454                 _M_gcount = 1;
 455               else
 456                 __err |= ios_base::eofbit;
 457             }
 458           catch(...)
 459             { this->_M_setstate(ios_base::badbit); }
 460         }
 461       if (!_M_gcount)
 462         __err |= ios_base::failbit;
 463       if (__err)
 464         this->setstate(__err);
 465       return __c;
 466     }
 467
 468   template<typename _CharT, typename _Traits>
 469     basic_istream<_CharT, _Traits>&
 470     basic_istream<_CharT, _Traits>::
 471     get(char_type& __c)
 472     {
 473       _M_gcount = 0;
 474       ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 475       sentry __cerb(*this, true);
 476       if (__cerb)
 477         {
 478           try
 479             {
 480               const int_type __cb = this->rdbuf()->sbumpc();
 481               // 27.6.1.1 paragraph 3
 482               if (!traits_type::eq_int_type(__cb, traits_type::eof()))
 483                 {
 484                   _M_gcount = 1;
 485                   __c = traits_type::to_char_type(__cb);
 486                 }
 487               else
 488                 __err |= ios_base::eofbit;
 489             }
 490           catch(...)
 491             { this->_M_setstate(ios_base::badbit); }
 492         }
 493       if (!_M_gcount)
 494         __err |= ios_base::failbit;
 495       if (__err)
 496         this->setstate(__err);
 497       return *this;
 498     }
 499
 500   template<typename _CharT, typename _Traits>
 501     basic_istream<_CharT, _Traits>&
 502     basic_istream<_CharT, _Traits>::
 503     get(char_type* __s, streamsize __n, char_type __delim)
 504     {
 505       _M_gcount = 0;
 506       ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 507       sentry __cerb(*this, true);
 508       if (__cerb)
 509         {
 510           try
 511             {
 512               const int_type __idelim = traits_type::to_int_type(__delim);
 513               const int_type __eof = traits_type::eof();
 514               __streambuf_type* __sb = this->rdbuf();
 515               int_type __c = __sb->sgetc();
 516
 517               while (_M_gcount + 1 < __n
 518                      && !traits_type::eq_int_type(__c, __eof)
 519                      && !traits_type::eq_int_type(__c, __idelim))
 520                 {
 521                   *__s++ = traits_type::to_char_type(__c);
 522                   ++_M_gcount;
 523                   __c = __sb->snextc();
 524                 }
 525               if (traits_type::eq_int_type(__c, __eof))
 526                 __err |= ios_base::eofbit;
 527             }
 528           catch(...)
 529             { this->_M_setstate(ios_base::badbit); }
 530         }
 531       *__s = char_type();
 532       if (!_M_gcount)
 533         __err |= ios_base::failbit;
 534       if (__err)
 535         this->setstate(__err);
 536       return *this;
 537     }
 538
 539   template<typename _CharT, typename _Traits>
 540     basic_istream<_CharT, _Traits>&
 541     basic_istream<_CharT, _Traits>::
 542     get(__streambuf_type& __sb, char_type __delim)
 543     {
 544       _M_gcount = 0;
 545       ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 546       sentry __cerb(*this, true);
 547       if (__cerb)
 548         {
 549           try
 550             {
 551               const int_type __idelim = traits_type::to_int_type(__delim);
 552               const int_type __eof = traits_type::eof();
 553               __streambuf_type* __this_sb = this->rdbuf();
 554               int_type __c = __this_sb->sgetc();
 555               char_type __c2 = traits_type::to_char_type(__c);
 556
 557               while (!traits_type::eq_int_type(__c, __eof)
 558                      && !traits_type::eq_int_type(__c, __idelim)
 559                      && !traits_type::eq_int_type(__sb.sputc(__c2), __eof))
 560                 {
 561                   ++_M_gcount;
 562                   __c = __this_sb->snextc();
 563                   __c2 = traits_type::to_char_type(__c);
 564                 }
 565               if (traits_type::eq_int_type(__c, __eof))
 566                 __err |= ios_base::eofbit;
 567             }
 568           catch(...)
 569             { this->_M_setstate(ios_base::badbit); }
 570         }
 571       if (!_M_gcount)
 572         __err |= ios_base::failbit;
 573       if (__err)
 574         this->setstate(__err);
 575       return *this;
 576     }
 577
 578   template<typename _CharT, typename _Traits>
 579     basic_istream<_CharT, _Traits>&
 580     basic_istream<_CharT, _Traits>::
 581     getline(char_type* __s, streamsize __n, char_type __delim)
 582     {
 583       _M_gcount = 0;
 584       ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 585       sentry __cerb(*this, true);
 586       if (__cerb)
 587         {
 588           try
 589             {
 590               const int_type __idelim = traits_type::to_int_type(__delim);
 591               const int_type __eof = traits_type::eof();
 592               __streambuf_type* __sb = this->rdbuf();
 593               int_type __c = __sb->sgetc();
 594
 595               while (_M_gcount + 1 < __n
 596                      && !traits_type::eq_int_type(__c, __eof)
 597                      && !traits_type::eq_int_type(__c, __idelim))
 598                 {
 599                   *__s++ = traits_type::to_char_type(__c);
 600                   __c = __sb->snextc();
 601                   ++_M_gcount;
 602                 }
 603               if (traits_type::eq_int_type(__c, __eof))
 604                 __err |= ios_base::eofbit;
 605               else
 606                 {
 607                   if (traits_type::eq_int_type(__c, __idelim))
 608                     {
 609                       __sb->sbumpc();
 610                       ++_M_gcount;
 611                     }
 612                   else
 613                     __err |= ios_base::failbit;
 614                 }
 615             }
 616           catch(...)
 617             { this->_M_setstate(ios_base::badbit); }
 618         }
 619       *__s = char_type();
 620       if (!_M_gcount)
 621         __err |= ios_base::failbit;
 622       if (__err)
 623         this->setstate(__err);
 624       return *this;
 625     }
 626
 627   // We provide three overloads, since the first two are much simpler
 628   // than the general case. Also, the latter two can thus adopt the
 629   // same "batchy" strategy used by getline above.
 630   template<typename _CharT, typename _Traits>
 631     basic_istream<_CharT, _Traits>&
 632     basic_istream<_CharT, _Traits>::
 633     ignore(void)
 634     {
 635       _M_gcount = 0;
 636       sentry __cerb(*this, true);
 637       if (__cerb)
 638         {
 639           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 640           try
 641             {
 642               const int_type __eof = traits_type::eof();
 643               __streambuf_type* __sb = this->rdbuf();
 644
 645               if (traits_type::eq_int_type(__sb->sbumpc(), __eof))
 646                 __err |= ios_base::eofbit;
 647               else
 648                 _M_gcount = 1;
 649             }
 650           catch(...)
 651             { this->_M_setstate(ios_base::badbit); }
 652           if (__err)
 653             this->setstate(__err);
 654         }
 655       return *this;
 656     }
 657
 658   template<typename _CharT, typename _Traits>
 659     basic_istream<_CharT, _Traits>&
 660     basic_istream<_CharT, _Traits>::
 661     ignore(streamsize __n)
 662     {
 663       if (__n == 1)
 664         return ignore();
 665
 666       _M_gcount = 0;
 667       sentry __cerb(*this, true);
 668       if (__cerb && __n > 0)
 669         {
 670           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 671           try
 672             {
 673               const int_type __eof = traits_type::eof();
 674               __streambuf_type* __sb = this->rdbuf();
 675               int_type __c = __eof;
 676
 677               if (__n != numeric_limits<streamsize>::max())
 678                 --__n;
 679               while (_M_gcount <= __n
 680                      && !traits_type::eq_int_type(__c = __sb->sbumpc(), __eof))
 681                 ++_M_gcount;
 682               if (traits_type::eq_int_type(__c, __eof))
 683                 __err |= ios_base::eofbit;
 684             }
 685           catch(...)
 686             { this->_M_setstate(ios_base::badbit); }
 687           if (__err)
 688             this->setstate(__err);
 689         }
 690       return *this;
 691     }
 692
 693   template<typename _CharT, typename _Traits>
 694     basic_istream<_CharT, _Traits>&
 695     basic_istream<_CharT, _Traits>::
 696     ignore(streamsize __n, int_type __delim)
 697     {
 698       if (traits_type::eq_int_type(__delim, traits_type::eof()))
 699         return ignore(__n);
 700
 701       _M_gcount = 0;
 702       sentry __cerb(*this, true);
 703       if (__cerb && __n > 0)
 704         {
 705           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 706           try
 707             {
 708               const int_type __eof = traits_type::eof();
 709               __streambuf_type* __sb = this->rdbuf();
 710               int_type __c = __eof;
 711
 712               if (__n != numeric_limits<streamsize>::max())
 713                 --__n;
 714               while (_M_gcount <= __n
 715                      && !traits_type::eq_int_type(__c = __sb->sbumpc(), __eof))
 716                 {
 717                   ++_M_gcount;
 718                   if (traits_type::eq_int_type(__c, __delim))
 719                     break;
 720                 }
 721               if (traits_type::eq_int_type(__c, __eof))
 722                 __err |= ios_base::eofbit;
 723             }
 724           catch(...)
 725             { this->_M_setstate(ios_base::badbit); }
 726           if (__err)
 727             this->setstate(__err);
 728         }
 729       return *this;
 730     }
 731
 732   template<typename _CharT, typename _Traits>
 733     typename basic_istream<_CharT, _Traits>::int_type
 734     basic_istream<_CharT, _Traits>::
 735     peek(void)
 736     {
 737       int_type __c = traits_type::eof();
 738       _M_gcount = 0;
 739       sentry __cerb(*this, true);
 740       if (__cerb)
 741         {
 742           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 743           try
 744             {
 745               __c = this->rdbuf()->sgetc();
 746               if (traits_type::eq_int_type(__c, traits_type::eof()))
 747                 __err |= ios_base::eofbit;
 748             }
 749           catch(...)
 750             { this->_M_setstate(ios_base::badbit); }
 751           if (__err)
 752             this->setstate(__err);
 753         }
 754       return __c;
 755     }
 756
 757   template<typename _CharT, typename _Traits>
 758     basic_istream<_CharT, _Traits>&
 759     basic_istream<_CharT, _Traits>::
 760     read(char_type* __s, streamsize __n)
 761     {
 762       _M_gcount = 0;
 763       sentry __cerb(*this, true);
 764       if (__cerb)
 765         {
 766           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 767           try
 768             {
 769               _M_gcount = this->rdbuf()->sgetn(__s, __n);
 770               if (_M_gcount != __n)
 771                 __err |= (ios_base::eofbit | ios_base::failbit);
 772             }
 773           catch(...)
 774             { this->_M_setstate(ios_base::badbit); }
 775           if (__err)
 776             this->setstate(__err);
 777         }
 778       return *this;
 779     }
 780
 781   template<typename _CharT, typename _Traits>
 782     streamsize
 783     basic_istream<_CharT, _Traits>::
 784     readsome(char_type* __s, streamsize __n)
 785     {
 786       _M_gcount = 0;
 787       sentry __cerb(*this, true);
 788       if (__cerb)
 789         {
 790           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 791           try
 792             {
 793               // Cannot compare int_type with streamsize generically.
 794               const streamsize __num = this->rdbuf()->in_avail();
 795               if (__num > 0)
 796                 _M_gcount = this->rdbuf()->sgetn(__s, std::min(__num, __n));
 797               else if (__num == -1)
 798                 __err |= ios_base::eofbit;
 799             }
 800           catch(...)
 801             { this->_M_setstate(ios_base::badbit); }
 802           if (__err)
 803             this->setstate(__err);
 804         }
 805       return _M_gcount;
 806     }
 807
 808   template<typename _CharT, typename _Traits>
 809     basic_istream<_CharT, _Traits>&
 810     basic_istream<_CharT, _Traits>::
 811     putback(char_type __c)
 812     {
 813       // _GLIBCXX_RESOLVE_LIB_DEFECTS
 814       // 60. What is a formatted input function?
 815       _M_gcount = 0;
 816       sentry __cerb(*this, true);
 817       if (__cerb)
 818         {
 819           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 820           try
 821             {
 822               const int_type __eof = traits_type::eof();
 823               __streambuf_type* __sb = this->rdbuf();
 824               if (!__sb
 825                   || traits_type::eq_int_type(__sb->sputbackc(__c), __eof))
 826                 __err |= ios_base::badbit;
 827             }
 828           catch(...)
 829             { this->_M_setstate(ios_base::badbit); }
 830           if (__err)
 831             this->setstate(__err);
 832         }
 833       return *this;
 834     }
 835
 836   template<typename _CharT, typename _Traits>
 837     basic_istream<_CharT, _Traits>&
 838     basic_istream<_CharT, _Traits>::
 839     unget(void)
 840     {
 841       // _GLIBCXX_RESOLVE_LIB_DEFECTS
 842       // 60. What is a formatted input function?
 843       _M_gcount = 0;
 844       sentry __cerb(*this, true);
 845       if (__cerb)
 846         {
 847           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 848           try
 849             {
 850               const int_type __eof = traits_type::eof();
 851               __streambuf_type* __sb = this->rdbuf();
 852               if (!__sb
 853                   || traits_type::eq_int_type(__sb->sungetc(), __eof))
 854                 __err |= ios_base::badbit;
 855             }
 856           catch(...)
 857             { this->_M_setstate(ios_base::badbit); }
 858           if (__err)
 859             this->setstate(__err);
 860         }
 861       return *this;
 862     }
 863
 864   template<typename _CharT, typename _Traits>
 865     int
 866     basic_istream<_CharT, _Traits>::
 867     sync(void)
 868     {
 869       // _GLIBCXX_RESOLVE_LIB_DEFECTS
 870       // DR60.  Do not change _M_gcount.
 871       int __ret = -1;
 872       sentry __cerb(*this, true);
 873       if (__cerb)
 874         {
 875           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 876           try
 877             {
 878               __streambuf_type* __sb = this->rdbuf();
 879               if (__sb)
 880                 {
 881                   if (__sb->pubsync() == -1)
 882                     __err |= ios_base::badbit;
 883                   else
 884                     __ret = 0;
 885                 }
 886             }
 887           catch(...)
 888             { this->_M_setstate(ios_base::badbit); }
 889           if (__err)
 890             this->setstate(__err);
 891         }
 892       return __ret;
 893     }
 894
 895   template<typename _CharT, typename _Traits>
 896     typename basic_istream<_CharT, _Traits>::pos_type
 897     basic_istream<_CharT, _Traits>::
 898     tellg(void)
 899     {
 900       // _GLIBCXX_RESOLVE_LIB_DEFECTS
 901       // DR60.  Do not change _M_gcount.
 902       pos_type __ret = pos_type(-1);
 903       try
 904         {
 905           if (!this->fail())
 906             __ret = this->rdbuf()->pubseekoff(0, ios_base::cur, ios_base::in);
 907         }
 908       catch(...)
 909         { this->_M_setstate(ios_base::badbit); }
 910       return __ret;
 911     }
 912
 913   template<typename _CharT, typename _Traits>
 914     basic_istream<_CharT, _Traits>&
 915     basic_istream<_CharT, _Traits>::
 916     seekg(pos_type __pos)
 917     {
 918       // _GLIBCXX_RESOLVE_LIB_DEFECTS
 919       // DR60.  Do not change _M_gcount.
 920       ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 921       try
 922         {
 923           if (!this->fail())
 924             {
 925               // 136.  seekp, seekg setting wrong streams?
 926               const pos_type __p = this->rdbuf()->pubseekpos(__pos,
 927                                                              ios_base::in);
 928
 929               // 129. Need error indication from seekp() and seekg()
 930               if (__p == pos_type(off_type(-1)))
 931                 __err |= ios_base::failbit;
 932             }
 933         }
 934       catch(...)
 935         { this->_M_setstate(ios_base::badbit); }
 936       if (__err)
 937         this->setstate(__err);
 938       return *this;
 939     }
 940
 941   template<typename _CharT, typename _Traits>
 942     basic_istream<_CharT, _Traits>&
 943     basic_istream<_CharT, _Traits>::
 944     seekg(off_type __off, ios_base::seekdir __dir)
 945     {
 946       // _GLIBCXX_RESOLVE_LIB_DEFECTS
 947       // DR60.  Do not change _M_gcount.
 948       ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 949       try
 950         {
 951           if (!this->fail())
 952             {
 953               // 136.  seekp, seekg setting wrong streams?
 954               const pos_type __p = this->rdbuf()->pubseekoff(__off, __dir,
 955                                                              ios_base::in);
 956
 957               // 129. Need error indication from seekp() and seekg()
 958               if (__p == pos_type(off_type(-1)))
 959                 __err |= ios_base::failbit;
 960             }
 961         }
 962       catch(...)
 963         { this->_M_setstate(ios_base::badbit); }
 964       if (__err)
 965         this->setstate(__err);
 966       return *this;
 967     }
 968
 969   // 27.6.1.2.3 Character extraction templates
 970   template<typename _CharT, typename _Traits>
 971     basic_istream<_CharT, _Traits>&
 972     operator>>(basic_istream<_CharT, _Traits>& __in, _CharT& __c)
 973     {
 974       typedef basic_istream<_CharT, _Traits>            __istream_type;
 975       typedef typename __istream_type::int_type         __int_type;
 976
 977       typename __istream_type::sentry __cerb(__in, false);
 978       if (__cerb)
 979         {
 980           ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 981           try
 982             {
 983               const __int_type __cb = __in.rdbuf()->sbumpc();
 984               if (!_Traits::eq_int_type(__cb, _Traits::eof()))
 985                 __c = _Traits::to_char_type(__cb);
 986               else
 987                 __err |= (ios_base::eofbit | ios_base::failbit);
 988             }
 989           catch(...)
 990             { __in._M_setstate(ios_base::badbit); }
 991           if (__err)
 992             __in.setstate(__err);
 993         }
 994       return __in;
 995     }
 996
 997   template<typename _CharT, typename _Traits>
 998     basic_istream<_CharT, _Traits>&
 999     operator>>(basic_istream<_CharT, _Traits>& __in, _CharT* __s)
1000     {
1001       typedef basic_istream<_CharT, _Traits>            __istream_type;
1002       typedef typename __istream_type::__streambuf_type __streambuf_type;
1003       typedef typename _Traits::int_type                int_type;
1004       typedef _CharT                                    char_type;
1005       typedef ctype<_CharT>                             __ctype_type;
1006
1007       streamsize __extracted = 0;
1008       ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
1009       typename __istream_type::sentry __cerb(__in, false);
1010       if (__cerb)
1011         {
1012           try
1013             {
1014               // Figure out how many characters to extract.
1015               streamsize __num = __in.width();
1016               if (__num <= 0)
1017                 __num = numeric_limits<streamsize>::max();
1018
1019               const __ctype_type& __ct = use_facet<__ctype_type>(__in.getloc());
1020
1021               const int_type __eof = _Traits::eof();
1022               __streambuf_type* __sb = __in.rdbuf();
1023               int_type __c = __sb->sgetc();
1024
1025               while (__extracted < __num - 1
1026                      && !_Traits::eq_int_type(__c, __eof)
1027                      && !__ct.is(ctype_base::space,
1028                                  _Traits::to_char_type(__c)))
1029                 {
1030                   *__s++ = _Traits::to_char_type(__c);
1031                   ++__extracted;
1032                   __c = __sb->snextc();
1033                 }
1034               if (_Traits::eq_int_type(__c, __eof))
1035                 __err |= ios_base::eofbit;
1036
1037               // _GLIBCXX_RESOLVE_LIB_DEFECTS
1038               // 68.  Extractors for char* should store null at end
1039               *__s = char_type();
1040               __in.width(0);
1041             }
1042           catch(...)
1043             { __in._M_setstate(ios_base::badbit); }
1044         }
1045       if (!__extracted)
1046         __err |= ios_base::failbit;
1047       if (__err)
1048         __in.setstate(__err);
1049       return __in;
1050     }
1051
1052   // 27.6.1.4 Standard basic_istream manipulators
1053   template<typename _CharT, typename _Traits>
1054     basic_istream<_CharT,_Traits>&
1055     ws(basic_istream<_CharT,_Traits>& __in)
1056     {
1057       typedef basic_istream<_CharT, _Traits>            __istream_type;
1058       typedef typename __istream_type::__streambuf_type __streambuf_type;
1059       typedef typename __istream_type::__ctype_type     __ctype_type;
1060       typedef typename __istream_type::int_type         __int_type;
1061
1062       const __ctype_type& __ct = use_facet<__ctype_type>(__in.getloc());
1063       const __int_type __eof = _Traits::eof();
1064       __streambuf_type* __sb = __in.rdbuf();
1065       __int_type __c = __sb->sgetc();
1066
1067       while (!_Traits::eq_int_type(__c, __eof)
1068              && __ct.is(ctype_base::space, _Traits::to_char_type(__c)))
1069         __c = __sb->snextc();
1070
1071        if (_Traits::eq_int_type(__c, __eof))
1072          __in.setstate(ios_base::eofbit);
1073       return __in;
1074     }
1075
1076   // 21.3.7.9 basic_string::getline and operators
1077   template<typename _CharT, typename _Traits, typename _Alloc>
1078     basic_istream<_CharT, _Traits>&
1079     operator>>(basic_istream<_CharT, _Traits>& __in,
1080                basic_string<_CharT, _Traits, _Alloc>& __str)
1081     {
1082       typedef basic_istream<_CharT, _Traits>            __istream_type;
1083       typedef typename __istream_type::int_type         __int_type;
1084       typedef typename __istream_type::__streambuf_type __streambuf_type;
1085       typedef typename __istream_type::__ctype_type     __ctype_type;
1086       typedef basic_string<_CharT, _Traits, _Alloc>     __string_type;
1087       typedef typename __string_type::size_type         __size_type;
1088
1089       __size_type __extracted = 0;
1090       ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
1091       typename __istream_type::sentry __cerb(__in, false);
1092       if (__cerb)
1093         {
1094           try
1095             {
1096               // Avoid reallocation for common case.
1097               __str.erase();
1098               _CharT __buf[128];
1099               __size_type __len = 0;
1100               const streamsize __w = __in.width();
1101               const __size_type __n = __w > 0 ? static_cast<__size_type>(__w)
1102                                               : __str.max_size();
1103               const __ctype_type& __ct = use_facet<__ctype_type>(__in.getloc());
1104               const __int_type __eof = _Traits::eof();
1105               __streambuf_type* __sb = __in.rdbuf();
1106               __int_type __c = __sb->sgetc();
1107
1108               while (__extracted < __n
1109                      && !_Traits::eq_int_type(__c, __eof)
1110                      && !__ct.is(ctype_base::space, _Traits::to_char_type(__c)))
1111                 {
1112                   if (__len == sizeof(__buf) / sizeof(_CharT))
1113                     {
1114                       __str.append(__buf, sizeof(__buf) / sizeof(_CharT));
1115                       __len = 0;
1116                     }
1117                   __buf[__len++] = _Traits::to_char_type(__c);
1118                   ++__extracted;
1119                   __c = __sb->snextc();
1120                 }
1121               __str.append(__buf, __len);
1122
1123               if (_Traits::eq_int_type(__c, __eof))
1124                 __err |= ios_base::eofbit;
1125               __in.width(0);
1126             }
1127           catch(...)
1128             {
1129               // _GLIBCXX_RESOLVE_LIB_DEFECTS
1130               // 91. Description of operator>> and getline() for string<>
1131               // might cause endless loop
1132               __in._M_setstate(ios_base::badbit);
1133             }
1134         }
1135       // 211.  operator>>(istream&, string&) doesn't set failbit
1136       if (!__extracted)
1137         __err |= ios_base::failbit;
1138       if (__err)
1139         __in.setstate(__err);
1140       return __in;
1141     }
1142
1143   template<typename _CharT, typename _Traits, typename _Alloc>
1144     basic_istream<_CharT, _Traits>&
1145     getline(basic_istream<_CharT, _Traits>& __in,
1146             basic_string<_CharT, _Traits, _Alloc>& __str, _CharT __delim)
1147     {
1148       typedef basic_istream<_CharT, _Traits>            __istream_type;
1149       typedef typename __istream_type::int_type         __int_type;
1150       typedef typename __istream_type::__streambuf_type __streambuf_type;
1151       typedef typename __istream_type::__ctype_type     __ctype_type;
1152       typedef basic_string<_CharT, _Traits, _Alloc>     __string_type;
1153       typedef typename __string_type::size_type         __size_type;
1154
1155       __size_type __extracted = 0;
1156       const __size_type __n = __str.max_size();
1157       ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
1158       typename __istream_type::sentry __cerb(__in, true);
1159       if (__cerb)
1160         {
1161           try
1162             {
1163               __str.erase();
1164               const __int_type __idelim = _Traits::to_int_type(__delim);
1165               const __int_type __eof = _Traits::eof();
1166               __streambuf_type* __sb = __in.rdbuf();
1167               __int_type __c = __sb->sgetc();
1168
1169               while (__extracted < __n
1170                      && !_Traits::eq_int_type(__c, __eof)
1171                      && !_Traits::eq_int_type(__c, __idelim))
1172                 {
1173                   __str += _Traits::to_char_type(__c);
1174                   ++__extracted;
1175                   __c = __sb->snextc();
1176                 }
1177
1178               if (_Traits::eq_int_type(__c, __eof))
1179                 __err |= ios_base::eofbit;
1180               else if (_Traits::eq_int_type(__c, __idelim))
1181                 {
1182                   ++__extracted;
1183                   __sb->sbumpc();
1184                 }
1185               else
1186                 __err |= ios_base::failbit;
1187             }
1188           catch(...)
1189             {
1190               // _GLIBCXX_RESOLVE_LIB_DEFECTS
1191               // 91. Description of operator>> and getline() for string<>
1192               // might cause endless loop
1193               __in._M_setstate(ios_base::badbit);
1194             }
1195         }
1196       if (!__extracted)
1197         __err |= ios_base::failbit;
1198       if (__err)
1199         __in.setstate(__err);
1200       return __in;
1201     }
1202
1203   template<class _CharT, class _Traits, class _Alloc>
1204     inline basic_istream<_CharT,_Traits>&
1205     getline(basic_istream<_CharT, _Traits>& __in,
1206             basic_string<_CharT,_Traits,_Alloc>& __str)
1207     { return getline(__in, __str, __in.widen('\n')); }
1208
1209   // Inhibit implicit instantiations for required instantiations,
1210   // which are defined via explicit instantiations elsewhere.
1211   // NB:  This syntax is a GNU extension.
1212 #if _GLIBCXX_EXTERN_TEMPLATE
1213   extern template class basic_istream<char>;
1214   extern template istream& ws(istream&);
1215   extern template istream& operator>>(istream&, char&);
1216   extern template istream& operator>>(istream&, char*);
1217   extern template istream& operator>>(istream&, unsigned char&);
1218   extern template istream& operator>>(istream&, signed char&);
1219   extern template istream& operator>>(istream&, unsigned char*);
1220   extern template istream& operator>>(istream&, signed char*);
1221
1222   extern template class basic_iostream<char>;
1223
1224 #ifdef _GLIBCXX_USE_WCHAR_T
1225   extern template class basic_istream<wchar_t>;
1226   extern template wistream& ws(wistream&);
1227   extern template wistream& operator>>(wistream&, wchar_t&);
1228   extern template wistream& operator>>(wistream&, wchar_t*);
1229
1230   extern template class basic_iostream<wchar_t>;
1231 #endif
1232 #endif
1233 } // namespace std
1234
1235 #endif