libstdc++-v3/src/debug.cc

   1 // Debugging mode support code -*- C++ -*-
   2
   3 // Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
   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 3, 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 // Under Section 7 of GPL version 3, you are granted additional
  18 // permissions described in the GCC Runtime Library Exception, version
  19 // 3.1, as published by the Free Software Foundation.
  20
  21 // You should have received a copy of the GNU General Public License and
  22 // a copy of the GCC Runtime Library Exception along with this program;
  23 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  24 // <http://www.gnu.org/licenses/>.
  25
  26 #include <debug/debug.h>
  27 #include <debug/safe_sequence.h>
  28 #include <debug/safe_iterator.h>
  29 #include <algorithm>
  30 #include <cassert>
  31 #include <cstring>
  32 #include <cctype>
  33 #include <cstdio>
  34 #include <cstdlib>
  35 #include <functional>
  36
  37 using namespace std;
  38
  39 namespace
  40 {
  41   /** Returns different instances of __mutex depending on the passed address
  42    *  in order to limit contention without breaking current library binary
  43    *  compatibility. */
  44   __gnu_cxx::__mutex&
  45   get_safe_base_mutex(void* __address)
  46   {
  47     const size_t mask = 0xf;
  48     static __gnu_cxx::__mutex safe_base_mutex[mask + 1];
  49     const size_t index = _Hash_impl::hash(__address) & mask;
  50     return safe_base_mutex[index];
  51   }
  52
  53   void
  54   swap_seq(__gnu_debug::_Safe_sequence_base& __lhs,
  55            __gnu_debug::_Safe_sequence_base& __rhs)
  56   {
  57     swap(__lhs._M_iterators, __rhs._M_iterators);
  58     swap(__lhs._M_const_iterators, __rhs._M_const_iterators);
  59     swap(__lhs._M_version, __rhs._M_version);
  60     __gnu_debug::_Safe_iterator_base* __iter;
  61     for (__iter = __rhs._M_iterators; __iter; __iter = __iter->_M_next)
  62       __iter->_M_sequence = &__rhs;
  63     for (__iter = __lhs._M_iterators; __iter; __iter = __iter->_M_next)
  64       __iter->_M_sequence = &__lhs;
  65     for (__iter = __rhs._M_const_iterators; __iter; __iter = __iter->_M_next)
  66       __iter->_M_sequence = &__rhs;
  67     for (__iter = __lhs._M_const_iterators; __iter; __iter = __iter->_M_next)
  68       __iter->_M_sequence = &__lhs;
  69   }
  70 } // anonymous namespace
  71
  72 namespace __gnu_debug
  73 {
  74   const char* _S_debug_messages[] =
  75   {
  76     "function requires a valid iterator range [%1.name;, %2.name;)",
  77     "attempt to insert into container with a singular iterator",
  78     "attempt to insert into container with an iterator"
  79     " from a different container",
  80     "attempt to erase from container with a %2.state; iterator",
  81     "attempt to erase from container with an iterator"
  82     " from a different container",
  83     "attempt to subscript container with out-of-bounds index %2;,"
  84     " but container only holds %3; elements",
  85     "attempt to access an element in an empty container",
  86     "elements in iterator range [%1.name;, %2.name;)"
  87     " are not partitioned by the value %3;",
  88     "elements in iterator range [%1.name;, %2.name;)"
  89     " are not partitioned by the predicate %3; and value %4;",
  90     "elements in iterator range [%1.name;, %2.name;) are not sorted",
  91     "elements in iterator range [%1.name;, %2.name;)"
  92     " are not sorted according to the predicate %3;",
  93     "elements in iterator range [%1.name;, %2.name;) do not form a heap",
  94     "elements in iterator range [%1.name;, %2.name;)"
  95     " do not form a heap with respect to the predicate %3;",
  96     "attempt to write through a singular bitset reference",
  97     "attempt to read from a singular bitset reference",
  98     "attempt to flip a singular bitset reference",
  99     "attempt to splice a list into itself",
 100     "attempt to splice lists with inequal allocators",
 101     "attempt to splice elements referenced by a %1.state; iterator",
 102     "attempt to splice an iterator from a different container",
 103     "splice destination %1.name;"
 104     " occurs within source range [%2.name;, %3.name;)",
 105     "attempt to initialize an iterator that will immediately become singular",
 106     "attempt to copy-construct an iterator from a singular iterator",
 107     "attempt to construct a constant iterator"
 108     " from a singular mutable iterator",
 109     "attempt to copy from a singular iterator",
 110     "attempt to dereference a %1.state; iterator",
 111     "attempt to increment a %1.state; iterator",
 112     "attempt to decrement a %1.state; iterator",
 113     "attempt to subscript a %1.state; iterator %2; step from"
 114     " its current position, which falls outside its dereferenceable range",
 115     "attempt to advance a %1.state; iterator %2; steps,"
 116     " which falls outside its valid range",
 117     "attempt to retreat a %1.state; iterator %2; steps,"
 118     " which falls outside its valid range",
 119     "attempt to compare a %1.state; iterator to a %2.state; iterator",
 120     "attempt to compare iterators from different sequences",
 121     "attempt to order a %1.state; iterator to a %2.state; iterator",
 122     "attempt to order iterators from different sequences",
 123     "attempt to compute the difference between a %1.state;"
 124     " iterator to a %2.state; iterator",
 125     "attempt to compute the different between two iterators"
 126     " from different sequences",
 127     "attempt to dereference an end-of-stream istream_iterator",
 128     "attempt to increment an end-of-stream istream_iterator",
 129     "attempt to output via an ostream_iterator with no associated stream",
 130     "attempt to dereference an end-of-stream istreambuf_iterator"
 131     " (this is a GNU extension)",
 132     "attempt to increment an end-of-stream istreambuf_iterator",
 133     "attempt to insert into container after an end iterator",
 134     "attempt to erase from container after a %2.state; iterator not followed"
 135     " by a dereferenceable one",
 136     "function requires a valid iterator range (%2.name;, %3.name;)"
 137     ", \"%2.name;\" shall be before and not equal to \"%3.name;\""
 138   };
 139
 140   void
 141   _Safe_sequence_base::
 142   _M_detach_all()
 143   {
 144     __gnu_cxx::__scoped_lock sentry(_M_get_mutex());
 145     for (_Safe_iterator_base* __iter = _M_iterators; __iter;)
 146       {
 147         _Safe_iterator_base* __old = __iter;
 148         __iter = __iter->_M_next;
 149         __old->_M_reset();
 150       }
 151     _M_iterators = 0;
 152
 153     for (_Safe_iterator_base* __iter2 = _M_const_iterators; __iter2;)
 154       {
 155         _Safe_iterator_base* __old = __iter2;
 156         __iter2 = __iter2->_M_next;
 157         __old->_M_reset();
 158       }
 159     _M_const_iterators = 0;
 160   }
 161
 162   void
 163   _Safe_sequence_base::
 164   _M_detach_singular()
 165   {
 166     __gnu_cxx::__scoped_lock sentry(_M_get_mutex());
 167     for (_Safe_iterator_base* __iter = _M_iterators; __iter;)
 168       {
 169         _Safe_iterator_base* __old = __iter;
 170         __iter = __iter->_M_next;
 171         if (__old->_M_singular())
 172           __old->_M_detach_single();
 173       }
 174
 175     for (_Safe_iterator_base* __iter2 = _M_const_iterators; __iter2;)
 176       {
 177         _Safe_iterator_base* __old = __iter2;
 178         __iter2 = __iter2->_M_next;
 179         if (__old->_M_singular())
 180           __old->_M_detach_single();
 181       }
 182   }
 183
 184   void
 185   _Safe_sequence_base::
 186   _M_revalidate_singular()
 187   {
 188     __gnu_cxx::__scoped_lock sentry(_M_get_mutex());
 189     for (_Safe_iterator_base* __iter = _M_iterators; __iter;
 190          __iter = __iter->_M_next)
 191       __iter->_M_version = _M_version;
 192
 193     for (_Safe_iterator_base* __iter2 = _M_const_iterators; __iter2;
 194          __iter2 = __iter2->_M_next)
 195       __iter2->_M_version = _M_version;
 196   }
 197
 198   void
 199   _Safe_sequence_base::
 200   _M_swap(_Safe_sequence_base& __x)
 201   {
 202     // We need to lock both sequences to swap
 203     using namespace __gnu_cxx;
 204     __mutex *__this_mutex = &_M_get_mutex();
 205     __mutex *__x_mutex = &__x._M_get_mutex();
 206     if (__this_mutex == __x_mutex)
 207       {
 208         __scoped_lock __lock(*__this_mutex);
 209         swap_seq(*this, __x);
 210       }
 211     else
 212       {
 213         __scoped_lock __l1(__this_mutex < __x_mutex
 214                              ? *__this_mutex : *__x_mutex);
 215         __scoped_lock __l2(__this_mutex < __x_mutex
 216                              ? *__x_mutex : *__this_mutex);
 217         swap_seq(*this, __x);
 218       }
 219   }
 220
 221   __gnu_cxx::__mutex&
 222   _Safe_sequence_base::
 223   _M_get_mutex() throw ()
 224   { return get_safe_base_mutex(this); }
 225
 226   void
 227   _Safe_sequence_base::
 228   _M_attach(_Safe_iterator_base* __it, bool __constant)
 229   {
 230     __gnu_cxx::__scoped_lock sentry(_M_get_mutex());
 231     _M_attach_single(__it, __constant);
 232   }
 233
 234   void
 235   _Safe_sequence_base::
 236   _M_attach_single(_Safe_iterator_base* __it, bool __constant) throw ()
 237   {
 238     _Safe_iterator_base*& __its =
 239       __constant ? _M_const_iterators : _M_iterators;
 240     __it->_M_next = __its;
 241     if (__it->_M_next)
 242       __it->_M_next->_M_prior = __it;
 243     __its = __it;
 244   }
 245
 246   void
 247   _Safe_sequence_base::
 248   _M_detach(_Safe_iterator_base* __it)
 249   {
 250     // Remove __it from this sequence's list
 251     __gnu_cxx::__scoped_lock sentry(_M_get_mutex());
 252     _M_detach_single(__it);
 253   }
 254
 255   void
 256   _Safe_sequence_base::
 257   _M_detach_single(_Safe_iterator_base* __it) throw ()
 258   {
 259     // Remove __it from this sequence's list
 260     if (__it->_M_prior)
 261       __it->_M_prior->_M_next = __it->_M_next;
 262     if (__it->_M_next)
 263       __it->_M_next->_M_prior = __it->_M_prior;
 264
 265     if (_M_const_iterators == __it)
 266       _M_const_iterators = __it->_M_next;
 267     if (_M_iterators == __it)
 268       _M_iterators = __it->_M_next;
 269   }
 270
 271   void
 272   _Safe_iterator_base::
 273   _M_attach(_Safe_sequence_base* __seq, bool __constant)
 274   {
 275     _M_detach();
 276
 277     // Attach to the new sequence (if there is one)
 278     if (__seq)
 279       {
 280         _M_sequence = __seq;
 281         _M_version = _M_sequence->_M_version;
 282         _M_sequence->_M_attach(this, __constant);
 283       }
 284   }
 285
 286   void
 287   _Safe_iterator_base::
 288   _M_attach_single(_Safe_sequence_base* __seq, bool __constant) throw ()
 289   {
 290     _M_detach_single();
 291
 292     // Attach to the new sequence (if there is one)
 293     if (__seq)
 294       {
 295         _M_sequence = __seq;
 296         _M_version = _M_sequence->_M_version;
 297         _M_sequence->_M_attach_single(this, __constant);
 298       }
 299   }
 300
 301   void
 302   _Safe_iterator_base::
 303   _M_detach()
 304   {
 305     if (_M_sequence)
 306       {
 307         _M_sequence->_M_detach(this);
 308       }
 309
 310     _M_reset();
 311   }
 312
 313   void
 314   _Safe_iterator_base::
 315   _M_detach_single() throw ()
 316   {
 317     if (_M_sequence)
 318       {
 319         _M_sequence->_M_detach_single(this);
 320       }
 321
 322     _M_reset();
 323   }
 324
 325   void
 326   _Safe_iterator_base::
 327   _M_reset() throw ()
 328   {
 329     _M_sequence = 0;
 330     _M_version = 0;
 331     _M_prior = 0;
 332     _M_next = 0;
 333   }
 334
 335   bool
 336   _Safe_iterator_base::
 337   _M_singular() const throw ()
 338   { return !_M_sequence || _M_version != _M_sequence->_M_version; }
 339
 340   bool
 341   _Safe_iterator_base::
 342   _M_can_compare(const _Safe_iterator_base& __x) const throw ()
 343   {
 344     return (!_M_singular()
 345             && !__x._M_singular() && _M_sequence == __x._M_sequence);
 346   }
 347
 348   __gnu_cxx::__mutex&
 349   _Safe_iterator_base::
 350   _M_get_mutex() throw ()
 351   { return get_safe_base_mutex(_M_sequence); }
 352
 353   void
 354   _Error_formatter::_Parameter::
 355   _M_print_field(const _Error_formatter* __formatter, const char* __name) const
 356   {
 357     assert(this->_M_kind != _Parameter::__unused_param);
 358     const int __bufsize = 64;
 359     char __buf[__bufsize];
 360
 361     if (_M_kind == __iterator)
 362       {
 363         if (strcmp(__name, "name") == 0)
 364           {
 365             assert(_M_variant._M_iterator._M_name);
 366             __formatter->_M_print_word(_M_variant._M_iterator._M_name);
 367           }
 368         else if (strcmp(__name, "address") == 0)
 369           {
 370             __formatter->_M_format_word(__buf, __bufsize, "%p",
 371                                         _M_variant._M_iterator._M_address);
 372             __formatter->_M_print_word(__buf);
 373           }
 374         else if (strcmp(__name, "type") == 0)
 375           {
 376             if (!_M_variant._M_iterator._M_type)
 377               __formatter->_M_print_word("<unknown type>");
 378             else
 379               // TBD: demangle!
 380               __formatter->_M_print_word(_M_variant._M_iterator.
 381                                          _M_type->name());
 382           }
 383         else if (strcmp(__name, "constness") == 0)
 384           {
 385             static const char* __constness_names[__last_constness] =
 386               {
 387                 "<unknown>",
 388                 "constant",
 389                 "mutable"
 390               };
 391             __formatter->_M_print_word(__constness_names[_M_variant.
 392                                                          _M_iterator.
 393                                                          _M_constness]);
 394           }
 395         else if (strcmp(__name, "state") == 0)
 396           {
 397             static const char* __state_names[__last_state] =
 398               {
 399                 "<unknown>",
 400                 "singular",
 401                 "dereferenceable (start-of-sequence)",
 402                 "dereferenceable",
 403                 "past-the-end",
 404                 "before-begin"
 405               };
 406             __formatter->_M_print_word(__state_names[_M_variant.
 407                                                      _M_iterator._M_state]);
 408           }
 409         else if (strcmp(__name, "sequence") == 0)
 410           {
 411             assert(_M_variant._M_iterator._M_sequence);
 412             __formatter->_M_format_word(__buf, __bufsize, "%p",
 413                                         _M_variant._M_iterator._M_sequence);
 414             __formatter->_M_print_word(__buf);
 415           }
 416         else if (strcmp(__name, "seq_type") == 0)
 417           {
 418             if (!_M_variant._M_iterator._M_seq_type)
 419               __formatter->_M_print_word("<unknown seq_type>");
 420             else
 421               // TBD: demangle!
 422               __formatter->_M_print_word(_M_variant._M_iterator.
 423                                          _M_seq_type->name());
 424           }
 425         else
 426           assert(false);
 427       }
 428     else if (_M_kind == __sequence)
 429       {
 430         if (strcmp(__name, "name") == 0)
 431           {
 432             assert(_M_variant._M_sequence._M_name);
 433             __formatter->_M_print_word(_M_variant._M_sequence._M_name);
 434           }
 435         else if (strcmp(__name, "address") == 0)
 436           {
 437             assert(_M_variant._M_sequence._M_address);
 438             __formatter->_M_format_word(__buf, __bufsize, "%p",
 439                                         _M_variant._M_sequence._M_address);
 440             __formatter->_M_print_word(__buf);
 441           }
 442         else if (strcmp(__name, "type") == 0)
 443           {
 444             if (!_M_variant._M_sequence._M_type)
 445               __formatter->_M_print_word("<unknown type>");
 446             else
 447               // TBD: demangle!
 448               __formatter->_M_print_word(_M_variant._M_sequence.
 449                                          _M_type->name());
 450           }
 451         else
 452           assert(false);
 453       }
 454     else if (_M_kind == __integer)
 455       {
 456         if (strcmp(__name, "name") == 0)
 457           {
 458             assert(_M_variant._M_integer._M_name);
 459             __formatter->_M_print_word(_M_variant._M_integer._M_name);
 460           }
 461         else
 462         assert(false);
 463       }
 464     else if (_M_kind == __string)
 465       {
 466         if (strcmp(__name, "name") == 0)
 467           {
 468             assert(_M_variant._M_string._M_name);
 469             __formatter->_M_print_word(_M_variant._M_string._M_name);
 470           }
 471         else
 472           assert(false);
 473       }
 474     else
 475       {
 476         assert(false);
 477       }
 478   }
 479
 480   void
 481   _Error_formatter::_Parameter::
 482   _M_print_description(const _Error_formatter* __formatter) const
 483   {
 484     const int __bufsize = 128;
 485     char __buf[__bufsize];
 486
 487     if (_M_kind == __iterator)
 488       {
 489         __formatter->_M_print_word("iterator ");
 490         if (_M_variant._M_iterator._M_name)
 491           {
 492             __formatter->_M_format_word(__buf, __bufsize, "\"%s\" ",
 493                                         _M_variant._M_iterator._M_name);
 494             __formatter->_M_print_word(__buf);
 495           }
 496
 497         __formatter->_M_format_word(__buf, __bufsize, "@ 0x%p {\n",
 498                                     _M_variant._M_iterator._M_address);
 499         __formatter->_M_print_word(__buf);
 500         if (_M_variant._M_iterator._M_type)
 501           {
 502             __formatter->_M_print_word("type = ");
 503             _M_print_field(__formatter, "type");
 504
 505             if (_M_variant._M_iterator._M_constness != __unknown_constness)
 506               {
 507                 __formatter->_M_print_word(" (");
 508                 _M_print_field(__formatter, "constness");
 509                 __formatter->_M_print_word(" iterator)");
 510               }
 511             __formatter->_M_print_word(";\n");
 512           }
 513
 514         if (_M_variant._M_iterator._M_state != __unknown_state)
 515           {
 516             __formatter->_M_print_word("  state = ");
 517             _M_print_field(__formatter, "state");
 518             __formatter->_M_print_word(";\n");
 519           }
 520
 521         if (_M_variant._M_iterator._M_sequence)
 522           {
 523             __formatter->_M_print_word("  references sequence ");
 524             if (_M_variant._M_iterator._M_seq_type)
 525               {
 526                 __formatter->_M_print_word("with type `");
 527                 _M_print_field(__formatter, "seq_type");
 528                 __formatter->_M_print_word("' ");
 529               }
 530
 531             __formatter->_M_format_word(__buf, __bufsize, "@ 0x%p\n",
 532                                         _M_variant._M_sequence._M_address);
 533             __formatter->_M_print_word(__buf);
 534           }
 535         __formatter->_M_print_word("}\n");
 536       }
 537     else if (_M_kind == __sequence)
 538       {
 539         __formatter->_M_print_word("sequence ");
 540         if (_M_variant._M_sequence._M_name)
 541           {
 542             __formatter->_M_format_word(__buf, __bufsize, "\"%s\" ",
 543                                         _M_variant._M_sequence._M_name);
 544             __formatter->_M_print_word(__buf);
 545           }
 546
 547         __formatter->_M_format_word(__buf, __bufsize, "@ 0x%p {\n",
 548                                     _M_variant._M_sequence._M_address);
 549         __formatter->_M_print_word(__buf);
 550
 551         if (_M_variant._M_sequence._M_type)
 552           {
 553             __formatter->_M_print_word("  type = ");
 554             _M_print_field(__formatter, "type");
 555             __formatter->_M_print_word(";\n");
 556           }
 557         __formatter->_M_print_word("}\n");
 558       }
 559   }
 560
 561   const _Error_formatter&
 562   _Error_formatter::_M_message(_Debug_msg_id __id) const throw ()
 563   { return this->_M_message(_S_debug_messages[__id]); }
 564
 565   void
 566   _Error_formatter::_M_error() const
 567   {
 568     const int __bufsize = 128;
 569     char __buf[__bufsize];
 570
 571     // Emit file & line number information
 572     _M_column = 1;
 573     _M_wordwrap = false;
 574     if (_M_file)
 575       {
 576         _M_format_word(__buf, __bufsize, "%s:", _M_file);
 577         _M_print_word(__buf);
 578         _M_column += strlen(__buf);
 579       }
 580
 581     if (_M_line > 0)
 582       {
 583         _M_format_word(__buf, __bufsize, "%u:", _M_line);
 584         _M_print_word(__buf);
 585         _M_column += strlen(__buf);
 586       }
 587
 588     if (_M_max_length)
 589       _M_wordwrap = true;
 590     _M_print_word("error: ");
 591
 592     // Print the error message
 593     assert(_M_text);
 594     _M_print_string(_M_text);
 595     _M_print_word(".\n");
 596
 597     // Emit descriptions of the objects involved in the operation
 598     _M_wordwrap = false;
 599     bool __has_noninteger_parameters = false;
 600     for (unsigned int __i = 0; __i < _M_num_parameters; ++__i)
 601       {
 602         if (_M_parameters[__i]._M_kind == _Parameter::__iterator
 603             || _M_parameters[__i]._M_kind == _Parameter::__sequence)
 604           {
 605             if (!__has_noninteger_parameters)
 606               {
 607                 _M_first_line = true;
 608                 _M_print_word("\nObjects involved in the operation:\n");
 609                 __has_noninteger_parameters = true;
 610               }
 611             _M_parameters[__i]._M_print_description(this);
 612           }
 613       }
 614
 615     abort();
 616   }
 617
 618   template<typename _Tp>
 619     void
 620     _Error_formatter::_M_format_word(char* __buf,
 621                                      int __n __attribute__ ((__unused__)),
 622                                      const char* __fmt, _Tp __s) const throw ()
 623     {
 624 #ifdef _GLIBCXX_USE_C99
 625       std::snprintf(__buf, __n, __fmt, __s);
 626 #else
 627       std::sprintf(__buf, __fmt, __s);
 628 #endif
 629     }
 630
 631
 632   void
 633   _Error_formatter::_M_print_word(const char* __word) const
 634   {
 635     if (!_M_wordwrap)
 636       {
 637         fprintf(stderr, "%s", __word);
 638         return;
 639       }
 640
 641     size_t __length = strlen(__word);
 642     if (__length == 0)
 643       return;
 644
 645     if ((_M_column + __length < _M_max_length)
 646         || (__length >= _M_max_length && _M_column == 1))
 647       {
 648         // If this isn't the first line, indent
 649         if (_M_column == 1 && !_M_first_line)
 650           {
 651             char __spacing[_M_indent + 1];
 652             for (int i = 0; i < _M_indent; ++i)
 653               __spacing[i] = ' ';
 654             __spacing[_M_indent] = '\0';
 655             fprintf(stderr, "%s", __spacing);
 656             _M_column += _M_indent;
 657           }
 658
 659         fprintf(stderr, "%s", __word);
 660         _M_column += __length;
 661
 662         if (__word[__length - 1] == '\n')
 663           {
 664             _M_first_line = false;
 665             _M_column = 1;
 666           }
 667       }
 668     else
 669       {
 670         _M_column = 1;
 671         _M_print_word("\n");
 672         _M_print_word(__word);
 673       }
 674   }
 675
 676   void
 677   _Error_formatter::
 678   _M_print_string(const char* __string) const
 679   {
 680     const char* __start = __string;
 681     const char* __finish = __start;
 682     const int __bufsize = 128;
 683     char __buf[__bufsize];
 684
 685     while (*__start)
 686       {
 687         if (*__start != '%')
 688           {
 689             // [__start, __finish) denotes the next word
 690             __finish = __start;
 691             while (isalnum(*__finish))
 692               ++__finish;
 693             if (__start == __finish)
 694               ++__finish;
 695             if (isspace(*__finish))
 696               ++__finish;
 697
 698             const ptrdiff_t __len = __finish - __start;
 699             assert(__len < __bufsize);
 700             memcpy(__buf, __start, __len);
 701             __buf[__len] = '\0';
 702             _M_print_word(__buf);
 703             __start = __finish;
 704
 705             // Skip extra whitespace
 706             while (*__start == ' ')
 707               ++__start;
 708
 709             continue;
 710           }
 711
 712         ++__start;
 713         assert(*__start);
 714         if (*__start == '%')
 715           {
 716             _M_print_word("%");
 717             ++__start;
 718             continue;
 719           }
 720
 721         // Get the parameter number
 722         assert(*__start >= '1' && *__start <= '9');
 723         size_t __param = *__start - '0';
 724         --__param;
 725         assert(__param < _M_num_parameters);
 726
 727         // '.' separates the parameter number from the field
 728         // name, if there is one.
 729         ++__start;
 730         if (*__start != '.')
 731           {
 732             assert(*__start == ';');
 733             ++__start;
 734             __buf[0] = '\0';
 735             if (_M_parameters[__param]._M_kind == _Parameter::__integer)
 736               {
 737                 _M_format_word(__buf, __bufsize, "%ld",
 738                                _M_parameters[__param]._M_variant._M_integer._M_value);
 739                 _M_print_word(__buf);
 740               }
 741             else if (_M_parameters[__param]._M_kind == _Parameter::__string)
 742               _M_print_string(_M_parameters[__param]._M_variant._M_string._M_value);
 743             continue;
 744           }
 745
 746         // Extract the field name we want
 747         enum { __max_field_len = 16 };
 748         char __field[__max_field_len];
 749         int __field_idx = 0;
 750         ++__start;
 751         while (*__start != ';')
 752           {
 753             assert(*__start);
 754             assert(__field_idx < __max_field_len-1);
 755             __field[__field_idx++] = *__start++;
 756           }
 757         ++__start;
 758         __field[__field_idx] = 0;
 759
 760         _M_parameters[__param]._M_print_field(this, __field);
 761       }
 762   }
 763
 764   void
 765   _Error_formatter::_M_get_max_length() const throw ()
 766   {
 767     const char* __nptr = std::getenv("GLIBCXX_DEBUG_MESSAGE_LENGTH");
 768     if (__nptr)
 769       {
 770         char* __endptr;
 771         const unsigned long __ret = std::strtoul(__nptr, &__endptr, 0);
 772         if (*__nptr != '\0' && *__endptr == '\0')
 773           _M_max_length = __ret;
 774       }
 775   }
 776
 777   // Instantiations.
 778   template
 779     void
 780     _Error_formatter::_M_format_word(char*, int, const char*,
 781                                      const void*) const;
 782
 783   template
 784     void
 785     _Error_formatter::_M_format_word(char*, int, const char*, long) const;
 786
 787   template
 788     void
 789     _Error_formatter::_M_format_word(char*, int, const char*,
 790                                      std::size_t) const;
 791
 792   template
 793     void
 794     _Error_formatter::_M_format_word(char*, int, const char*,
 795                                      const char*) const;
 796 } // namespace __gnu_debug