# functions.h

Go to the documentation of this file.

    00001 // Debugging support implementation -*- C++ -*-
    00002
    00003 // Copyright (C) 2003, 2005, 2006
    00004 // Free Software Foundation, Inc.
    00005 //
    00006 // This file is part of the GNU ISO C++ Library.  This library is free
    00007 // software; you can redistribute it and/or modify it under the
    00008 // terms of the GNU General Public License as published by the
    00009 // Free Software Foundation; either version 2, or (at your option)
    00010 // any later version.
    00011
    00012 // This library is distributed in the hope that it will be useful,
    00013 // but WITHOUT ANY WARRANTY; without even the implied warranty of
    00014 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    00015 // GNU General Public License for more details.
    00016
    00017 // You should have received a copy of the GNU General Public License along
    00018 // with this library; see the file COPYING.  If not, write to the Free
    00019 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
    00020 // USA.
    00021
    00022 // As a special exception, you may use this file as part of a free software
    00023 // library without restriction.  Specifically, if other files instantiate
    00024 // templates or use macros or inline functions from this file, or you compile
    00025 // this file and link it with other files to produce an executable, this
    00026 // file does not by itself cause the resulting executable to be covered by
    00027 // the GNU General Public License.  This exception does not however
    00028 // invalidate any other reasons why the executable file might be covered by
    00029 // the GNU General Public License.
    00030
    00031 /** @file debug/functions.h
    00032  *  This file is a GNU debug extension to the Standard C++ Library.
    00033  */
    00034
    00035 #ifndef _GLIBCXX_DEBUG_FUNCTIONS_H
    00036 #define _GLIBCXX_DEBUG_FUNCTIONS_H 1
    00037
    00038 #include <bits/c++config.h>
    00039 #include <stddef.h>                       // for ptrdiff_t
    00040 #include <bits/stl_iterator_base_types.h> // for iterator_traits, categories
    00041 #include <bits/cpp_type_traits.h>         // for __is_integer
    00042
    00043 namespace __gnu_debug
    00044 {
    00045   template<typename _Iterator, typename _Sequence>
    00046     class _Safe_iterator;
    00047
    00048   // An arbitrary iterator pointer is not singular.
    00049   inline bool
    00050   __check_singular_aux(const void*) { return false; }
    00051
    00052   // We may have an iterator that derives from _Safe_iterator_base but isn't
    00053   // a _Safe_iterator.
    00054   template<typename _Iterator>
    00055     inline bool
    00056     __check_singular(_Iterator& __x)
    00057     { return __check_singular_aux(&__x); }
    00058
    00059   /** Non-NULL pointers are nonsingular. */
    00060   template<typename _Tp>
    00061     inline bool
    00062     __check_singular(const _Tp* __ptr)
    00063     { return __ptr == 0; }
    00064
    00065   /** Safe iterators know if they are singular. */
    00066   template<typename _Iterator, typename _Sequence>
    00067     inline bool
    00068     __check_singular(const _Safe_iterator<_Iterator, _Sequence>& __x)
    00069     { return __x._M_singular(); }
    00070
    00071   /** Assume that some arbitrary iterator is dereferenceable, because we
    00072       can't prove that it isn't. */
    00073   template<typename _Iterator>
    00074     inline bool
    00075     __check_dereferenceable(_Iterator&)
    00076     { return true; }
    00077
    00078   /** Non-NULL pointers are dereferenceable. */
    00079   template<typename _Tp>
    00080     inline bool
    00081     __check_dereferenceable(const _Tp* __ptr)
    00082     { return __ptr; }
    00083
    00084   /** Safe iterators know if they are singular. */
    00085   template<typename _Iterator, typename _Sequence>
    00086     inline bool
    00087     __check_dereferenceable(const _Safe_iterator<_Iterator, _Sequence>& __x)
    00088     { return __x._M_dereferenceable(); }
    00089
    00090   /** If the distance between two random access iterators is
    00091    *  nonnegative, assume the range is valid.
    00092   */
    00093   template<typename _RandomAccessIterator>
    00094     inline bool
    00095     __valid_range_aux2(const _RandomAccessIterator& __first,
    00096                const _RandomAccessIterator& __last,
    00097                std::random_access_iterator_tag)
    00098     { return __last - __first >= 0; }
    00099
    00100   /** Can't test for a valid range with input iterators, because
    00101    *  iteration may be destructive. So we just assume that the range
    00102    *  is valid.
    00103   */
    00104   template<typename _InputIterator>
    00105     inline bool
    00106     __valid_range_aux2(const _InputIterator&, const _InputIterator&,
    00107                std::input_iterator_tag)
    00108     { return true; }
    00109
    00110   /** We say that integral types for a valid range, and defer to other
    00111    *  routines to realize what to do with integral types instead of
    00112    *  iterators.
    00113   */
    00114   template<typename _Integral>
    00115     inline bool
    00116     __valid_range_aux(const _Integral&, const _Integral&, std::__true_type)
    00117     { return true; }
    00118
    00119   /** We have iterators, so figure out what kind of iterators that are
    00120    *  to see if we can check the range ahead of time.
    00121   */
    00122   template<typename _InputIterator>
    00123     inline bool
    00124     __valid_range_aux(const _InputIterator& __first,
    00125               const _InputIterator& __last, std::__false_type)
    00126   {
    00127     typedef typename std::iterator_traits<_InputIterator>::iterator_category
    00128       _Category;
    00129     return __valid_range_aux2(__first, __last, _Category());
    00130   }
    00131
    00132   /** Don't know what these iterators are, or if they are even
    00133    *  iterators (we may get an integral type for InputIterator), so
    00134    *  see if they are integral and pass them on to the next phase
    00135    *  otherwise.
    00136   */
    00137   template<typename _InputIterator>
    00138     inline bool
    00139     __valid_range(const _InputIterator& __first, const _InputIterator& __last)
    00140     {
    00141       typedef typename std::__is_integer<_InputIterator>::__type _Integral;
    00142       return __valid_range_aux(__first, __last, _Integral());
    00143     }
    00144
    00145   /** Safe iterators know how to check if they form a valid range. */
    00146   template<typename _Iterator, typename _Sequence>
    00147     inline bool
    00148     __valid_range(const _Safe_iterator<_Iterator, _Sequence>& __first,
    00149           const _Safe_iterator<_Iterator, _Sequence>& __last)
    00150     { return __first._M_valid_range(__last); }
    00151
    00152   /* Checks that [first, last) is a valid range, and then returns
    00153    * __first. This routine is useful when we can't use a separate
    00154    * assertion statement because, e.g., we are in a constructor.
    00155   */
    00156   template<typename _InputIterator>
    00157     inline _InputIterator
    00158     __check_valid_range(const _InputIterator& __first,
    00159             const _InputIterator& __last
    00160             __attribute__((__unused__)))
    00161     {
    00162       _GLIBCXX_DEBUG_ASSERT(__valid_range(__first, __last));
    00163       return __first;
    00164     }
    00165
    00166   /** Checks that __s is non-NULL or __n == 0, and then returns __s. */
    00167   template<typename _CharT, typename _Integer>
    00168     inline const _CharT*
    00169     __check_string(const _CharT* __s,
    00170            const _Integer& __n __attribute__((__unused__)))
    00171     {
    00172 #ifdef _GLIBCXX_DEBUG_PEDANTIC
    00173       _GLIBCXX_DEBUG_ASSERT(__s != 0 || __n == 0);
    00174 #endif
    00175       return __s;
    00176     }
    00177
    00178   /** Checks that __s is non-NULL and then returns __s. */
    00179   template<typename _CharT>
    00180     inline const _CharT*
    00181     __check_string(const _CharT* __s)
    00182     {
    00183 #ifdef _GLIBCXX_DEBUG_PEDANTIC
    00184       _GLIBCXX_DEBUG_ASSERT(__s != 0);
    00185 #endif
    00186       return __s;
    00187     }
    00188
    00189   // Can't check if an input iterator sequence is sorted, because we
    00190   // can't step through the sequence.
    00191   template<typename _InputIterator>
    00192     inline bool
    00193     __check_sorted_aux(const _InputIterator&, const _InputIterator&,
    00194                        std::input_iterator_tag)
    00195     { return true; }
    00196
    00197   // Can verify if a forward iterator sequence is in fact sorted using
    00198   // std::__is_sorted
    00199   template<typename _ForwardIterator>
    00200     inline bool
    00201     __check_sorted_aux(_ForwardIterator __first, _ForwardIterator __last,
    00202                        std::forward_iterator_tag)
    00203     {
    00204       if (__first == __last)
    00205         return true;
    00206
    00207       _ForwardIterator __next = __first;
    00208       for (++__next; __next != __last; __first = __next, ++__next) {
    00209         if (*__next < *__first)
    00210           return false;
    00211       }
    00212
    00213       return true;
    00214     }
    00215
    00216   // Can't check if an input iterator sequence is sorted, because we can't step
    00217   // through the sequence.
    00218   template<typename _InputIterator, typename _Predicate>
    00219     inline bool
    00220     __check_sorted_aux(const _InputIterator&, const _InputIterator&,
    00221                        _Predicate, std::input_iterator_tag)
    00222     { return true; }
    00223
    00224   // Can verify if a forward iterator sequence is in fact sorted using
    00225   // std::__is_sorted
    00226   template<typename _ForwardIterator, typename _Predicate>
    00227     inline bool
    00228     __check_sorted_aux(_ForwardIterator __first, _ForwardIterator __last,
    00229                        _Predicate __pred, std::forward_iterator_tag)
    00230     {
    00231       if (__first == __last)
    00232         return true;
    00233
    00234       _ForwardIterator __next = __first;
    00235       for (++__next; __next != __last; __first = __next, ++__next) {
    00236         if (__pred(*__next, *__first))
    00237           return false;
    00238       }
    00239
    00240       return true;
    00241     }
    00242
    00243   // Determine if a sequence is sorted.
    00244   template<typename _InputIterator>
    00245     inline bool
    00246     __check_sorted(const _InputIterator& __first, const _InputIterator& __last)
    00247     {
    00248       typedef typename std::iterator_traits<_InputIterator>::iterator_category
    00249         _Category;
    00250       return __check_sorted_aux(__first, __last, _Category());
    00251     }
    00252
    00253   template<typename _InputIterator, typename _Predicate>
    00254     inline bool
    00255     __check_sorted(const _InputIterator& __first, const _InputIterator& __last,
    00256                    _Predicate __pred)
    00257     {
    00258       typedef typename std::iterator_traits<_InputIterator>::iterator_category
    00259         _Category;
    00260       return __check_sorted_aux(__first, __last, __pred,
    00261                          _Category());
    00262     }
    00263
    00264   // _GLIBCXX_RESOLVE_LIB_DEFECTS
    00265   // 270. Binary search requirements overly strict
    00266   // Determine if a sequence is partitioned w.r.t. this element.
    00267   template<typename _ForwardIterator, typename _Tp>
    00268     inline bool
    00269     __check_partitioned(_ForwardIterator __first, _ForwardIterator __last,
    00270             const _Tp& __value)
    00271     {
    00272       while (__first != __last && *__first < __value)
    00273     ++__first;
    00274       while (__first != __last && !(*__first < __value))
    00275     ++__first;
    00276       return __first == __last;
    00277     }
    00278
    00279   // Determine if a sequence is partitioned w.r.t. this element.
    00280   template<typename _ForwardIterator, typename _Tp, typename _Pred>
    00281     inline bool
    00282     __check_partitioned(_ForwardIterator __first, _ForwardIterator __last,
    00283             const _Tp& __value, _Pred __pred)
    00284     {
    00285       while (__first != __last && __pred(*__first, __value))
    00286     ++__first;
    00287       while (__first != __last && !__pred(*__first, __value))
    00288     ++__first;
    00289       return __first == __last;
    00290     }
    00291 } // namespace __gnu_debug
    00292
    00293 #endif