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

   1 // Debugging support implementation -*- C++ -*-
   2
   3 // Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
   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 /** @file debug/functions.h
  27  *  This file is a GNU debug extension to the Standard C++ Library.
  28  */
  29
  30 #ifndef _GLIBCXX_DEBUG_FUNCTIONS_H
  31 #define _GLIBCXX_DEBUG_FUNCTIONS_H 1
  32
  33 #include <bits/c++config.h>
  34 #include <bits/stl_iterator_base_types.h> // for iterator_traits, categories
  35 #include <bits/cpp_type_traits.h>         // for __is_integer
  36 #include <debug/formatter.h>
  37
  38 namespace __gnu_debug
  39 {
  40   template<typename _Iterator, typename _Sequence>
  41     class _Safe_iterator;
  42
  43   // An arbitrary iterator pointer is not singular.
  44   inline bool
  45   __check_singular_aux(const void*) { return false; }
  46
  47   // We may have an iterator that derives from _Safe_iterator_base but isn't
  48   // a _Safe_iterator.
  49   template<typename _Iterator>
  50     inline bool
  51     __check_singular(_Iterator& __x)
  52     { return __check_singular_aux(&__x); }
  53
  54   /** Non-NULL pointers are nonsingular. */
  55   template<typename _Tp>
  56     inline bool
  57     __check_singular(const _Tp* __ptr)
  58     { return __ptr == 0; }
  59
  60   /** Safe iterators know if they are singular. */
  61   template<typename _Iterator, typename _Sequence>
  62     inline bool
  63     __check_singular(const _Safe_iterator<_Iterator, _Sequence>& __x)
  64     { return __x._M_singular(); }
  65
  66   /** Assume that some arbitrary iterator is dereferenceable, because we
  67       can't prove that it isn't. */
  68   template<typename _Iterator>
  69     inline bool
  70     __check_dereferenceable(_Iterator&)
  71     { return true; }
  72
  73   /** Non-NULL pointers are dereferenceable. */
  74   template<typename _Tp>
  75     inline bool
  76     __check_dereferenceable(const _Tp* __ptr)
  77     { return __ptr; }
  78
  79   /** Safe iterators know if they are singular. */
  80   template<typename _Iterator, typename _Sequence>
  81     inline bool
  82     __check_dereferenceable(const _Safe_iterator<_Iterator, _Sequence>& __x)
  83     { return __x._M_dereferenceable(); }
  84
  85   /** If the distance between two random access iterators is
  86    *  nonnegative, assume the range is valid.
  87   */
  88   template<typename _RandomAccessIterator>
  89     inline bool
  90     __valid_range_aux2(const _RandomAccessIterator& __first,
  91                        const _RandomAccessIterator& __last,
  92                        std::random_access_iterator_tag)
  93     { return __last - __first >= 0; }
  94
  95   /** Can't test for a valid range with input iterators, because
  96    *  iteration may be destructive. So we just assume that the range
  97    *  is valid.
  98   */
  99   template<typename _InputIterator>
 100     inline bool
 101     __valid_range_aux2(const _InputIterator&, const _InputIterator&,
 102                        std::input_iterator_tag)
 103     { return true; }
 104
 105   /** We say that integral types for a valid range, and defer to other
 106    *  routines to realize what to do with integral types instead of
 107    *  iterators.
 108   */
 109   template<typename _Integral>
 110     inline bool
 111     __valid_range_aux(const _Integral&, const _Integral&, std::__true_type)
 112     { return true; }
 113
 114   /** We have iterators, so figure out what kind of iterators that are
 115    *  to see if we can check the range ahead of time.
 116   */
 117   template<typename _InputIterator>
 118     inline bool
 119     __valid_range_aux(const _InputIterator& __first,
 120                       const _InputIterator& __last, std::__false_type)
 121   {
 122     typedef typename std::iterator_traits<_InputIterator>::iterator_category
 123       _Category;
 124     return __valid_range_aux2(__first, __last, _Category());
 125   }
 126
 127   /** Don't know what these iterators are, or if they are even
 128    *  iterators (we may get an integral type for InputIterator), so
 129    *  see if they are integral and pass them on to the next phase
 130    *  otherwise.
 131   */
 132   template<typename _InputIterator>
 133     inline bool
 134     __valid_range(const _InputIterator& __first, const _InputIterator& __last)
 135     {
 136       typedef typename std::__is_integer<_InputIterator>::__type _Integral;
 137       return __valid_range_aux(__first, __last, _Integral());
 138     }
 139
 140   /** Safe iterators know how to check if they form a valid range. */
 141   template<typename _Iterator, typename _Sequence>
 142     inline bool
 143     __valid_range(const _Safe_iterator<_Iterator, _Sequence>& __first,
 144                   const _Safe_iterator<_Iterator, _Sequence>& __last)
 145     { return __first._M_valid_range(__last); }
 146
 147   /** Safe local iterators know how to check if they form a valid range. */
 148   template<typename _Iterator, typename _Sequence>
 149     inline bool
 150     __valid_range(const _Safe_local_iterator<_Iterator, _Sequence>& __first,
 151                   const _Safe_local_iterator<_Iterator, _Sequence>& __last)
 152     { return __first._M_valid_range(__last); }
 153
 154   /* Checks that [first, last) is a valid range, and then returns
 155    * __first. This routine is useful when we can't use a separate
 156    * assertion statement because, e.g., we are in a constructor.
 157   */
 158   template<typename _InputIterator>
 159     inline _InputIterator
 160     __check_valid_range(const _InputIterator& __first,
 161                         const _InputIterator& __last
 162                         __attribute__((__unused__)))
 163     {
 164       __glibcxx_check_valid_range(__first, __last);
 165       return __first;
 166     }
 167
 168   /** Checks that __s is non-NULL or __n == 0, and then returns __s. */
 169   template<typename _CharT, typename _Integer>
 170     inline const _CharT*
 171     __check_string(const _CharT* __s,
 172                    const _Integer& __n __attribute__((__unused__)))
 173     {
 174 #ifdef _GLIBCXX_DEBUG_PEDANTIC
 175       __glibcxx_assert(__s != 0 || __n == 0);
 176 #endif
 177       return __s;
 178     }
 179
 180   /** Checks that __s is non-NULL and then returns __s. */
 181   template<typename _CharT>
 182     inline const _CharT*
 183     __check_string(const _CharT* __s)
 184     {
 185 #ifdef _GLIBCXX_DEBUG_PEDANTIC
 186       __glibcxx_assert(__s != 0);
 187 #endif
 188       return __s;
 189     }
 190
 191   // Can't check if an input iterator sequence is sorted, because we
 192   // can't step through the sequence.
 193   template<typename _InputIterator>
 194     inline bool
 195     __check_sorted_aux(const _InputIterator&, const _InputIterator&,
 196                        std::input_iterator_tag)
 197     { return true; }
 198
 199   // Can verify if a forward iterator sequence is in fact sorted using
 200   // std::__is_sorted
 201   template<typename _ForwardIterator>
 202     inline bool
 203     __check_sorted_aux(_ForwardIterator __first, _ForwardIterator __last,
 204                        std::forward_iterator_tag)
 205     {
 206       if (__first == __last)
 207         return true;
 208
 209       _ForwardIterator __next = __first;
 210       for (++__next; __next != __last; __first = __next, ++__next)
 211         if (*__next < *__first)
 212           return false;
 213
 214       return true;
 215     }
 216
 217   // Can't check if an input iterator sequence is sorted, because we can't step
 218   // through the sequence.
 219   template<typename _InputIterator, typename _Predicate>
 220     inline bool
 221     __check_sorted_aux(const _InputIterator&, const _InputIterator&,
 222                        _Predicate, std::input_iterator_tag)
 223     { return true; }
 224
 225   // Can verify if a forward iterator sequence is in fact sorted using
 226   // std::__is_sorted
 227   template<typename _ForwardIterator, typename _Predicate>
 228     inline bool
 229     __check_sorted_aux(_ForwardIterator __first, _ForwardIterator __last,
 230                        _Predicate __pred, std::forward_iterator_tag)
 231     {
 232       if (__first == __last)
 233         return true;
 234
 235       _ForwardIterator __next = __first;
 236       for (++__next; __next != __last; __first = __next, ++__next)
 237         if (__pred(*__next, *__first))
 238           return false;
 239
 240       return true;
 241     }
 242
 243   // Determine if a sequence is sorted.
 244   template<typename _InputIterator>
 245     inline bool
 246     __check_sorted(const _InputIterator& __first, const _InputIterator& __last)
 247     {
 248       typedef typename std::iterator_traits<_InputIterator>::iterator_category
 249         _Category;
 250
 251       // Verify that the < operator for elements in the sequence is a
 252       // StrictWeakOrdering by checking that it is irreflexive.
 253       __glibcxx_assert(__first == __last || !(*__first < *__first));
 254
 255       return __check_sorted_aux(__first, __last, _Category());
 256     }
 257
 258   template<typename _InputIterator, typename _Predicate>
 259     inline bool
 260     __check_sorted(const _InputIterator& __first, const _InputIterator& __last,
 261                    _Predicate __pred)
 262     {
 263       typedef typename std::iterator_traits<_InputIterator>::iterator_category
 264         _Category;
 265
 266       // Verify that the predicate is StrictWeakOrdering by checking that it
 267       // is irreflexive.
 268       __glibcxx_assert(__first == __last || !__pred(*__first, *__first));
 269
 270       return __check_sorted_aux(__first, __last, __pred, _Category());
 271     }
 272
 273   template<typename _InputIterator>
 274     inline bool
 275     __check_sorted_set_aux(const _InputIterator& __first,
 276                            const _InputIterator& __last,
 277                            std::__true_type)
 278     { return __check_sorted(__first, __last); }
 279
 280   template<typename _InputIterator>
 281     inline bool
 282     __check_sorted_set_aux(const _InputIterator&,
 283                            const _InputIterator&,
 284                            std::__false_type)
 285     { return true; }
 286
 287   template<typename _InputIterator, typename _Predicate>
 288     inline bool
 289     __check_sorted_set_aux(const _InputIterator& __first,
 290                            const _InputIterator& __last,
 291                            _Predicate __pred, std::__true_type)
 292     { return __check_sorted(__first, __last, __pred); }
 293
 294   template<typename _InputIterator, typename _Predicate>
 295     inline bool
 296     __check_sorted_set_aux(const _InputIterator&,
 297                            const _InputIterator&, _Predicate,
 298                            std::__false_type)
 299     { return true; }
 300
 301   // ... special variant used in std::merge, std::includes, std::set_*.
 302   template<typename _InputIterator1, typename _InputIterator2>
 303     inline bool
 304     __check_sorted_set(const _InputIterator1& __first,
 305                        const _InputIterator1& __last,
 306                        const _InputIterator2&)
 307     {
 308       typedef typename std::iterator_traits<_InputIterator1>::value_type
 309         _ValueType1;
 310       typedef typename std::iterator_traits<_InputIterator2>::value_type
 311         _ValueType2;
 312
 313       typedef typename std::__are_same<_ValueType1, _ValueType2>::__type
 314         _SameType;
 315       return __check_sorted_set_aux(__first, __last, _SameType());
 316     }
 317
 318   template<typename _InputIterator1, typename _InputIterator2,
 319            typename _Predicate>
 320     inline bool
 321     __check_sorted_set(const _InputIterator1& __first,
 322                        const _InputIterator1& __last,
 323                        const _InputIterator2&, _Predicate __pred)
 324     {
 325       typedef typename std::iterator_traits<_InputIterator1>::value_type
 326         _ValueType1;
 327       typedef typename std::iterator_traits<_InputIterator2>::value_type
 328         _ValueType2;
 329
 330       typedef typename std::__are_same<_ValueType1, _ValueType2>::__type
 331         _SameType;
 332       return __check_sorted_set_aux(__first, __last, __pred, _SameType());
 333    }
 334
 335   // _GLIBCXX_RESOLVE_LIB_DEFECTS
 336   // 270. Binary search requirements overly strict
 337   // Determine if a sequence is partitioned w.r.t. this element.
 338   template<typename _ForwardIterator, typename _Tp>
 339     inline bool
 340     __check_partitioned_lower(_ForwardIterator __first,
 341                               _ForwardIterator __last, const _Tp& __value)
 342     {
 343       while (__first != __last && *__first < __value)
 344         ++__first;
 345       while (__first != __last && !(*__first < __value))
 346         ++__first;
 347       return __first == __last;
 348     }
 349
 350   template<typename _ForwardIterator, typename _Tp>
 351     inline bool
 352     __check_partitioned_upper(_ForwardIterator __first,
 353                               _ForwardIterator __last, const _Tp& __value)
 354     {
 355       while (__first != __last && !(__value < *__first))
 356         ++__first;
 357       while (__first != __last && __value < *__first)
 358         ++__first;
 359       return __first == __last;
 360     }
 361
 362   // Determine if a sequence is partitioned w.r.t. this element.
 363   template<typename _ForwardIterator, typename _Tp, typename _Pred>
 364     inline bool
 365     __check_partitioned_lower(_ForwardIterator __first,
 366                               _ForwardIterator __last, const _Tp& __value,
 367                               _Pred __pred)
 368     {
 369       while (__first != __last && bool(__pred(*__first, __value)))
 370         ++__first;
 371       while (__first != __last && !bool(__pred(*__first, __value)))
 372         ++__first;
 373       return __first == __last;
 374     }
 375
 376   template<typename _ForwardIterator, typename _Tp, typename _Pred>
 377     inline bool
 378     __check_partitioned_upper(_ForwardIterator __first,
 379                               _ForwardIterator __last, const _Tp& __value,
 380                               _Pred __pred)
 381     {
 382       while (__first != __last && !bool(__pred(__value, *__first)))
 383         ++__first;
 384       while (__first != __last && bool(__pred(__value, *__first)))
 385         ++__first;
 386       return __first == __last;
 387     }
 388 } // namespace __gnu_debug
 389
 390 #endif