libstdc++-v3/include/ext/vstring_util.h

   1 // Versatile string utility -*- C++ -*-
   2
   3 // Copyright (C) 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 /** @file ext/vstring_util.h
  27  *  This file is a GNU extension to the Standard C++ Library.
  28  *  This is an internal header file, included by other library headers.
  29  *  You should not attempt to use it directly.
  30  */
  31
  32 #ifndef _VSTRING_UTIL_H
  33 #define _VSTRING_UTIL_H 1
  34
  35 #pragma GCC system_header
  36
  37 #include <ext/vstring_fwd.h>
  38 #include <debug/debug.h>
  39 #include <bits/stl_function.h>  // For less
  40 #include <bits/functexcept.h>
  41 #include <bits/localefwd.h>
  42 #include <bits/ostream_insert.h>
  43 #include <bits/stl_iterator.h>
  44 #include <ext/numeric_traits.h>
  45 #include <bits/move.h>
  46 #include <bits/range_access.h>
  47
  48 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
  49
  50   template<typename _CharT, typename _Traits, typename _Alloc>
  51     struct __vstring_utility
  52     {
  53       typedef typename _Alloc::template rebind<_CharT>::other _CharT_alloc_type;
  54
  55       typedef _Traits                                       traits_type;
  56       typedef typename _Traits::char_type                   value_type;
  57       typedef typename _CharT_alloc_type::size_type         size_type;
  58       typedef typename _CharT_alloc_type::difference_type   difference_type;
  59       typedef typename _CharT_alloc_type::pointer           pointer;
  60       typedef typename _CharT_alloc_type::const_pointer     const_pointer;
  61
  62       // For __sso_string.
  63       typedef __gnu_cxx::
  64       __normal_iterator<pointer, __gnu_cxx::
  65                         __versa_string<_CharT, _Traits, _Alloc,
  66                                        __sso_string_base> >
  67         __sso_iterator;
  68       typedef __gnu_cxx::
  69       __normal_iterator<const_pointer, __gnu_cxx::
  70                         __versa_string<_CharT, _Traits, _Alloc,
  71                                        __sso_string_base> >
  72         __const_sso_iterator;
  73
  74       // For __rc_string.
  75       typedef __gnu_cxx::
  76       __normal_iterator<pointer, __gnu_cxx::
  77                         __versa_string<_CharT, _Traits, _Alloc,
  78                                        __rc_string_base> >
  79         __rc_iterator;
  80       typedef __gnu_cxx::
  81       __normal_iterator<const_pointer, __gnu_cxx::
  82                         __versa_string<_CharT, _Traits, _Alloc,
  83                                        __rc_string_base> >
  84         __const_rc_iterator;
  85
  86       // NB:  When the allocator is empty, deriving from it saves space
  87       // (http://www.cantrip.org/emptyopt.html).
  88       template<typename _Alloc1>
  89         struct _Alloc_hider
  90         : public _Alloc1
  91         {
  92           _Alloc_hider(_CharT* __ptr)
  93           : _Alloc1(), _M_p(__ptr) { }
  94
  95           _Alloc_hider(const _Alloc1& __a, _CharT* __ptr)
  96           : _Alloc1(__a), _M_p(__ptr) { }
  97
  98           _CharT*  _M_p; // The actual data.
  99         };
 100
 101       // When __n = 1 way faster than the general multichar
 102       // traits_type::copy/move/assign.
 103       static void
 104       _S_copy(_CharT* __d, const _CharT* __s, size_type __n)
 105       {
 106         if (__n == 1)
 107           traits_type::assign(*__d, *__s);
 108         else
 109           traits_type::copy(__d, __s, __n);
 110       }
 111
 112       static void
 113       _S_move(_CharT* __d, const _CharT* __s, size_type __n)
 114       {
 115         if (__n == 1)
 116           traits_type::assign(*__d, *__s);
 117         else
 118           traits_type::move(__d, __s, __n);
 119       }
 120
 121       static void
 122       _S_assign(_CharT* __d, size_type __n, _CharT __c)
 123       {
 124         if (__n == 1)
 125           traits_type::assign(*__d, __c);
 126         else
 127           traits_type::assign(__d, __n, __c);
 128       }
 129
 130       // _S_copy_chars is a separate template to permit specialization
 131       // to optimize for the common case of pointers as iterators.
 132       template<typename _Iterator>
 133         static void
 134         _S_copy_chars(_CharT* __p, _Iterator __k1, _Iterator __k2)
 135         {
 136           for (; __k1 != __k2; ++__k1, ++__p)
 137             traits_type::assign(*__p, *__k1); // These types are off.
 138         }
 139
 140       static void
 141       _S_copy_chars(_CharT* __p, __sso_iterator __k1, __sso_iterator __k2)
 142       { _S_copy_chars(__p, __k1.base(), __k2.base()); }
 143
 144       static void
 145       _S_copy_chars(_CharT* __p, __const_sso_iterator __k1,
 146                     __const_sso_iterator __k2)
 147       { _S_copy_chars(__p, __k1.base(), __k2.base()); }
 148
 149       static void
 150       _S_copy_chars(_CharT* __p, __rc_iterator __k1, __rc_iterator __k2)
 151       { _S_copy_chars(__p, __k1.base(), __k2.base()); }
 152
 153       static void
 154       _S_copy_chars(_CharT* __p, __const_rc_iterator __k1,
 155                     __const_rc_iterator __k2)
 156       { _S_copy_chars(__p, __k1.base(), __k2.base()); }
 157
 158       static void
 159       _S_copy_chars(_CharT* __p, _CharT* __k1, _CharT* __k2)
 160       { _S_copy(__p, __k1, __k2 - __k1); }
 161
 162       static void
 163       _S_copy_chars(_CharT* __p, const _CharT* __k1, const _CharT* __k2)
 164       { _S_copy(__p, __k1, __k2 - __k1); }
 165
 166       static int
 167       _S_compare(size_type __n1, size_type __n2)
 168       {
 169         const difference_type __d = difference_type(__n1 - __n2);
 170
 171         if (__d > __numeric_traits_integer<int>::__max)
 172           return __numeric_traits_integer<int>::__max;
 173         else if (__d < __numeric_traits_integer<int>::__min)
 174           return __numeric_traits_integer<int>::__min;
 175         else
 176           return int(__d);
 177       }
 178     };
 179
 180 _GLIBCXX_END_NAMESPACE
 181
 182 #endif /* _VSTRING_UTIL_H */