libstdc++-v3/include/debug/functions.h

   1 // Debugging support implementation -*- C++ -*-
   2
   3 // Copyright (C) 2003-2020 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 debug/functions.h
  26  *  This file is a GNU debug extension to the Standard C++ Library.
  27  */
  28
  29 #ifndef _GLIBCXX_DEBUG_FUNCTIONS_H
  30 #define _GLIBCXX_DEBUG_FUNCTIONS_H 1
  31
  32 #include <bits/stl_function.h>  // for less
  33
  34 #if __cplusplus >= 201103L
  35 # include <bits/stl_iterator.h> // for __miter_base
  36 # include <type_traits>         // for is_lvalue_reference and conditional.
  37 #endif
  38
  39 #include <debug/helper_functions.h>
  40 #include <debug/formatter.h>
  41
  42 namespace __gnu_debug
  43 {
  44   template<typename _Sequence>
  45     struct _Insert_range_from_self_is_safe
  46     { enum { __value = 0 }; };
  47
  48   template<typename _Sequence>
  49     struct _Is_contiguous_sequence : std::__false_type { };
  50
  51   /* Checks that [first, last) is a valid range, and then returns
  52    * __first. This routine is useful when we can't use a separate
  53    * assertion statement because, e.g., we are in a constructor.
  54   */
  55   template<typename _InputIterator>
  56     inline _InputIterator
  57     __check_valid_range(const _InputIterator& __first,
  58                         const _InputIterator& __last,
  59                         const char* __file,
  60                         unsigned int __line,
  61                         const char* __function)
  62     {
  63       __glibcxx_check_valid_range_at(__first, __last,
  64                                      __file, __line, __function);
  65       return __first;
  66     }
  67
  68   /* Handle the case where __other is a pointer to _Sequence::value_type. */
  69   template<typename _Iterator, typename _Sequence, typename _Category>
  70     inline bool
  71     __foreign_iterator_aux4(
  72         const _Safe_iterator<_Iterator, _Sequence, _Category>& __it,
  73         const typename _Sequence::value_type* __other)
  74     {
  75       typedef const typename _Sequence::value_type* _PointerType;
  76       typedef std::less<_PointerType> _Less;
  77 #if __cplusplus >= 201103L
  78       constexpr _Less __l{};
  79 #else
  80       const _Less __l = _Less();
  81 #endif
  82       const _Sequence* __seq = __it._M_get_sequence();
  83       const _PointerType __begin = std::__addressof(*__seq->_M_base().begin());
  84       const _PointerType __end = std::__addressof(*(__seq->_M_base().end()-1));
  85
  86       // Check whether __other points within the contiguous storage.
  87       return __l(__other, __begin) || __l(__end, __other);
  88     }
  89
  90   /* Fallback overload for when we can't tell, assume it is valid. */
  91   template<typename _Iterator, typename _Sequence, typename _Category>
  92     inline bool
  93     __foreign_iterator_aux4(
  94         const _Safe_iterator<_Iterator, _Sequence, _Category>&, ...)
  95     { return true; }
  96
  97   /* Handle sequences with contiguous storage */
  98   template<typename _Iterator, typename _Sequence, typename _Category,
  99            typename _InputIterator>
 100     inline bool
 101     __foreign_iterator_aux3(
 102         const _Safe_iterator<_Iterator, _Sequence, _Category>& __it,
 103         const _InputIterator& __other, const _InputIterator& __other_end,
 104         std::__true_type)
 105     {
 106       if (__other == __other_end)
 107         return true;  // inserting nothing is safe even if not foreign iters
 108       if (__it._M_get_sequence()->empty())
 109         return true;  // can't be self-inserting if self is empty
 110       return __foreign_iterator_aux4(__it, std::__addressof(*__other));
 111     }
 112
 113   /* Handle non-contiguous containers, assume it is valid. */
 114   template<typename _Iterator, typename _Sequence, typename _Category,
 115            typename _InputIterator>
 116     inline bool
 117     __foreign_iterator_aux3(
 118         const _Safe_iterator<_Iterator, _Sequence, _Category>&,
 119         const _InputIterator&, const _InputIterator&,
 120         std::__false_type)
 121     { return true; }
 122
 123   /** Handle debug iterators from the same type of container. */
 124   template<typename _Iterator, typename _Sequence, typename _Category,
 125            typename _OtherIterator>
 126     inline bool
 127     __foreign_iterator_aux2(
 128         const _Safe_iterator<_Iterator, _Sequence, _Category>& __it,
 129         const _Safe_iterator<_OtherIterator, _Sequence, _Category>& __other,
 130         const _Safe_iterator<_OtherIterator, _Sequence, _Category>&)
 131     { return __it._M_get_sequence() != __other._M_get_sequence(); }
 132
 133   /** Handle debug iterators from different types of container. */
 134   template<typename _Iterator, typename _Sequence, typename _Category,
 135            typename _OtherIterator, typename _OtherSequence,
 136            typename _OtherCategory>
 137     inline bool
 138     __foreign_iterator_aux2(
 139         const _Safe_iterator<_Iterator, _Sequence, _Category>&,
 140         const _Safe_iterator<_OtherIterator, _OtherSequence,
 141                              _OtherCategory>&,
 142         const _Safe_iterator<_OtherIterator, _OtherSequence,
 143                              _OtherCategory>&)
 144     { return true; }
 145
 146   /* Handle non-debug iterators. */
 147   template<typename _Iterator, typename _Sequence, typename _Category,
 148            typename _InputIterator>
 149     inline bool
 150     __foreign_iterator_aux2(
 151         const _Safe_iterator<_Iterator, _Sequence, _Category>& __it,
 152         const _InputIterator& __other,
 153         const _InputIterator& __other_end)
 154     {
 155 #if __cplusplus < 201103L
 156       typedef _Is_contiguous_sequence<_Sequence> __tag;
 157 #else
 158       using __lvalref = std::is_lvalue_reference<
 159         typename std::iterator_traits<_InputIterator>::reference>;
 160       using __contiguous = _Is_contiguous_sequence<_Sequence>;
 161       using __tag = typename std::conditional<__lvalref::value, __contiguous,
 162                                               std::__false_type>::type;
 163 #endif
 164       return __foreign_iterator_aux3(__it, __other, __other_end, __tag());
 165     }
 166
 167   /* Handle the case where we aren't really inserting a range after all */
 168   template<typename _Iterator, typename _Sequence, typename _Category,
 169            typename _Integral>
 170     inline bool
 171     __foreign_iterator_aux(
 172         const _Safe_iterator<_Iterator, _Sequence, _Category>&,
 173         _Integral, _Integral, std::__true_type)
 174     { return true; }
 175
 176   /* Handle all iterators. */
 177   template<typename _Iterator, typename _Sequence, typename _Category,
 178            typename _InputIterator>
 179     inline bool
 180     __foreign_iterator_aux(
 181         const _Safe_iterator<_Iterator, _Sequence, _Category>& __it,
 182         _InputIterator __other, _InputIterator __other_end,
 183         std::__false_type)
 184     {
 185       return _Insert_range_from_self_is_safe<_Sequence>::__value
 186         || __foreign_iterator_aux2(__it, std::__miter_base(__other),
 187                                    std::__miter_base(__other_end));
 188     }
 189
 190   template<typename _Iterator, typename _Sequence, typename _Category,
 191            typename _InputIterator>
 192     inline bool
 193     __foreign_iterator(
 194         const _Safe_iterator<_Iterator, _Sequence, _Category>& __it,
 195         _InputIterator __other, _InputIterator __other_end)
 196     {
 197       typedef typename std::__is_integer<_InputIterator>::__type _Integral;
 198       return __foreign_iterator_aux(__it, __other, __other_end, _Integral());
 199     }
 200
 201   // Can't check if an input iterator sequence is sorted, because we
 202   // can't step through the sequence.
 203   template<typename _InputIterator>
 204     _GLIBCXX20_CONSTEXPR
 205     inline bool
 206     __check_sorted_aux(const _InputIterator&, const _InputIterator&,
 207                        std::input_iterator_tag)
 208     { return true; }
 209
 210   // Can verify if a forward iterator sequence is in fact sorted using
 211   // std::__is_sorted
 212   template<typename _ForwardIterator>
 213     _GLIBCXX20_CONSTEXPR
 214     inline bool
 215     __check_sorted_aux(_ForwardIterator __first, _ForwardIterator __last,
 216                        std::forward_iterator_tag)
 217     {
 218       if (__first == __last)
 219         return true;
 220
 221       _ForwardIterator __next = __first;
 222       for (++__next; __next != __last; __first = __next, (void)++__next)
 223         if (*__next < *__first)
 224           return false;
 225
 226       return true;
 227     }
 228
 229   // Can't check if an input iterator sequence is sorted, because we can't step
 230   // through the sequence.
 231   template<typename _InputIterator, typename _Predicate>
 232     _GLIBCXX20_CONSTEXPR
 233     inline bool
 234     __check_sorted_aux(const _InputIterator&, const _InputIterator&,
 235                        _Predicate, std::input_iterator_tag)
 236     { return true; }
 237
 238   // Can verify if a forward iterator sequence is in fact sorted using
 239   // std::__is_sorted
 240   template<typename _ForwardIterator, typename _Predicate>
 241     _GLIBCXX20_CONSTEXPR
 242     inline bool
 243     __check_sorted_aux(_ForwardIterator __first, _ForwardIterator __last,
 244                        _Predicate __pred, std::forward_iterator_tag)
 245     {
 246       if (__first == __last)
 247         return true;
 248
 249       _ForwardIterator __next = __first;
 250       for (++__next; __next != __last; __first = __next, (void)++__next)
 251         if (__pred(*__next, *__first))
 252           return false;
 253
 254       return true;
 255     }
 256
 257   // Determine if a sequence is sorted.
 258   template<typename _InputIterator>
 259     _GLIBCXX20_CONSTEXPR
 260     inline bool
 261     __check_sorted(const _InputIterator& __first, const _InputIterator& __last)
 262     {
 263       return __check_sorted_aux(__first, __last,
 264                                 std::__iterator_category(__first));
 265     }
 266
 267   template<typename _InputIterator, typename _Predicate>
 268     _GLIBCXX20_CONSTEXPR
 269     inline bool
 270     __check_sorted(const _InputIterator& __first, const _InputIterator& __last,
 271                    _Predicate __pred)
 272     {
 273       return __check_sorted_aux(__first, __last, __pred,
 274                                 std::__iterator_category(__first));
 275     }
 276
 277   template<typename _InputIterator>
 278     _GLIBCXX20_CONSTEXPR
 279     inline bool
 280     __check_sorted_set_aux(const _InputIterator& __first,
 281                            const _InputIterator& __last,
 282                            std::__true_type)
 283     { return __check_sorted(__first, __last); }
 284
 285   template<typename _InputIterator>
 286     _GLIBCXX20_CONSTEXPR
 287     inline bool
 288     __check_sorted_set_aux(const _InputIterator&,
 289                            const _InputIterator&,
 290                            std::__false_type)
 291     { return true; }
 292
 293   template<typename _InputIterator, typename _Predicate>
 294     _GLIBCXX20_CONSTEXPR
 295     inline bool
 296     __check_sorted_set_aux(const _InputIterator& __first,
 297                            const _InputIterator& __last,
 298                            _Predicate __pred, std::__true_type)
 299     { return __check_sorted(__first, __last, __pred); }
 300
 301   template<typename _InputIterator, typename _Predicate>
 302     _GLIBCXX20_CONSTEXPR
 303     inline bool
 304     __check_sorted_set_aux(const _InputIterator&,
 305                            const _InputIterator&, _Predicate,
 306                            std::__false_type)
 307     { return true; }
 308
 309   // ... special variant used in std::merge, std::includes, std::set_*.
 310   template<typename _InputIterator1, typename _InputIterator2>
 311     _GLIBCXX20_CONSTEXPR
 312     inline bool
 313     __check_sorted_set(const _InputIterator1& __first,
 314                        const _InputIterator1& __last,
 315                        const _InputIterator2&)
 316     {
 317       typedef typename std::iterator_traits<_InputIterator1>::value_type
 318         _ValueType1;
 319       typedef typename std::iterator_traits<_InputIterator2>::value_type
 320         _ValueType2;
 321
 322       typedef typename std::__are_same<_ValueType1, _ValueType2>::__type
 323         _SameType;
 324       return __check_sorted_set_aux(__first, __last, _SameType());
 325     }
 326
 327   template<typename _InputIterator1, typename _InputIterator2,
 328            typename _Predicate>
 329     _GLIBCXX20_CONSTEXPR
 330     inline bool
 331     __check_sorted_set(const _InputIterator1& __first,
 332                        const _InputIterator1& __last,
 333                        const _InputIterator2&, _Predicate __pred)
 334     {
 335       typedef typename std::iterator_traits<_InputIterator1>::value_type
 336         _ValueType1;
 337       typedef typename std::iterator_traits<_InputIterator2>::value_type
 338         _ValueType2;
 339
 340       typedef typename std::__are_same<_ValueType1, _ValueType2>::__type
 341         _SameType;
 342       return __check_sorted_set_aux(__first, __last, __pred, _SameType());
 343    }
 344
 345   // _GLIBCXX_RESOLVE_LIB_DEFECTS
 346   // 270. Binary search requirements overly strict
 347   // Determine if a sequence is partitioned w.r.t. this element.
 348   template<typename _ForwardIterator, typename _Tp>
 349     _GLIBCXX20_CONSTEXPR
 350     inline bool
 351     __check_partitioned_lower(_ForwardIterator __first,
 352                               _ForwardIterator __last, const _Tp& __value)
 353     {
 354       while (__first != __last && *__first < __value)
 355         ++__first;
 356       if (__first != __last)
 357         {
 358           ++__first;
 359           while (__first != __last && !(*__first < __value))
 360             ++__first;
 361         }
 362       return __first == __last;
 363     }
 364
 365   template<typename _ForwardIterator, typename _Tp>
 366     _GLIBCXX20_CONSTEXPR
 367     inline bool
 368     __check_partitioned_upper(_ForwardIterator __first,
 369                               _ForwardIterator __last, const _Tp& __value)
 370     {
 371       while (__first != __last && !(__value < *__first))
 372         ++__first;
 373       if (__first != __last)
 374         {
 375           ++__first;
 376           while (__first != __last && __value < *__first)
 377             ++__first;
 378         }
 379       return __first == __last;
 380     }
 381
 382   // Determine if a sequence is partitioned w.r.t. this element.
 383   template<typename _ForwardIterator, typename _Tp, typename _Pred>
 384     _GLIBCXX20_CONSTEXPR
 385     inline bool
 386     __check_partitioned_lower(_ForwardIterator __first,
 387                               _ForwardIterator __last, const _Tp& __value,
 388                               _Pred __pred)
 389     {
 390       while (__first != __last && bool(__pred(*__first, __value)))
 391         ++__first;
 392       if (__first != __last)
 393         {
 394           ++__first;
 395           while (__first != __last && !bool(__pred(*__first, __value)))
 396             ++__first;
 397         }
 398       return __first == __last;
 399     }
 400
 401   template<typename _ForwardIterator, typename _Tp, typename _Pred>
 402     _GLIBCXX20_CONSTEXPR
 403     inline bool
 404     __check_partitioned_upper(_ForwardIterator __first,
 405                               _ForwardIterator __last, const _Tp& __value,
 406                               _Pred __pred)
 407     {
 408       while (__first != __last && !bool(__pred(__value, *__first)))
 409         ++__first;
 410       if (__first != __last)
 411         {
 412           ++__first;
 413           while (__first != __last && bool(__pred(__value, *__first)))
 414             ++__first;
 415         }
 416       return __first == __last;
 417     }
 418
 419 #if __cplusplus >= 201103L
 420   struct _Irreflexive_checker
 421   {
 422     template<typename _It>
 423       static typename std::iterator_traits<_It>::reference
 424       __deref();
 425
 426     template<typename _It,
 427              typename = decltype(__deref<_It>() < __deref<_It>())>
 428       _GLIBCXX20_CONSTEXPR
 429       static bool
 430       _S_is_valid(_It __it)
 431       { return !(*__it < *__it); }
 432
 433     // Fallback method if operator doesn't exist.
 434     template<typename... _Args>
 435       _GLIBCXX20_CONSTEXPR
 436       static bool
 437       _S_is_valid(_Args...)
 438       { return true; }
 439
 440     template<typename _It, typename _Pred, typename
 441         = decltype(std::declval<_Pred>()(__deref<_It>(), __deref<_It>()))>
 442       _GLIBCXX20_CONSTEXPR
 443       static bool
 444       _S_is_valid_pred(_It __it, _Pred __pred)
 445       { return !__pred(*__it, *__it); }
 446
 447     // Fallback method if predicate can't be invoked.
 448     template<typename... _Args>
 449       _GLIBCXX20_CONSTEXPR
 450       static bool
 451       _S_is_valid_pred(_Args...)
 452       { return true; }
 453   };
 454
 455   template<typename _Iterator>
 456     _GLIBCXX20_CONSTEXPR
 457     inline bool
 458     __is_irreflexive(_Iterator __it)
 459     { return _Irreflexive_checker::_S_is_valid(__it); }
 460
 461   template<typename _Iterator, typename _Pred>
 462     _GLIBCXX20_CONSTEXPR
 463     inline bool
 464     __is_irreflexive_pred(_Iterator __it, _Pred __pred)
 465     { return _Irreflexive_checker::_S_is_valid_pred(__it, __pred); }
 466 #endif
 467
 468 } // namespace __gnu_debug
 469
 470 #endif