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