libstdc++
vstring_util.h
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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 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
48 {
49 _GLIBCXX_BEGIN_NAMESPACE_VERSION
50 
51  template<typename _CharT, typename _Traits, typename _Alloc>
52  struct __vstring_utility
53  {
54  typedef typename _Alloc::template rebind<_CharT>::other _CharT_alloc_type;
55 
56  typedef _Traits traits_type;
57  typedef typename _Traits::char_type value_type;
58  typedef typename _CharT_alloc_type::size_type size_type;
59  typedef typename _CharT_alloc_type::difference_type difference_type;
60  typedef typename _CharT_alloc_type::pointer pointer;
61  typedef typename _CharT_alloc_type::const_pointer const_pointer;
62 
63  // For __sso_string.
64  typedef __gnu_cxx::
65  __normal_iterator<pointer, __gnu_cxx::
66  __versa_string<_CharT, _Traits, _Alloc,
67  __sso_string_base> >
68  __sso_iterator;
69  typedef __gnu_cxx::
70  __normal_iterator<const_pointer, __gnu_cxx::
71  __versa_string<_CharT, _Traits, _Alloc,
72  __sso_string_base> >
73  __const_sso_iterator;
74 
75  // For __rc_string.
76  typedef __gnu_cxx::
77  __normal_iterator<pointer, __gnu_cxx::
78  __versa_string<_CharT, _Traits, _Alloc,
79  __rc_string_base> >
80  __rc_iterator;
81  typedef __gnu_cxx::
82  __normal_iterator<const_pointer, __gnu_cxx::
83  __versa_string<_CharT, _Traits, _Alloc,
84  __rc_string_base> >
85  __const_rc_iterator;
86 
87  // NB: When the allocator is empty, deriving from it saves space
88  // (http://www.cantrip.org/emptyopt.html).
89  template<typename _Alloc1>
90  struct _Alloc_hider
91  : public _Alloc1
92  {
93  _Alloc_hider(_CharT* __ptr)
94  : _Alloc1(), _M_p(__ptr) { }
95 
96  _Alloc_hider(const _Alloc1& __a, _CharT* __ptr)
97  : _Alloc1(__a), _M_p(__ptr) { }
98 
99  _CharT* _M_p; // The actual data.
100  };
101 
102  // When __n = 1 way faster than the general multichar
103  // traits_type::copy/move/assign.
104  static void
105  _S_copy(_CharT* __d, const _CharT* __s, size_type __n)
106  {
107  if (__n == 1)
108  traits_type::assign(*__d, *__s);
109  else
110  traits_type::copy(__d, __s, __n);
111  }
112 
113  static void
114  _S_move(_CharT* __d, const _CharT* __s, size_type __n)
115  {
116  if (__n == 1)
117  traits_type::assign(*__d, *__s);
118  else
119  traits_type::move(__d, __s, __n);
120  }
121 
122  static void
123  _S_assign(_CharT* __d, size_type __n, _CharT __c)
124  {
125  if (__n == 1)
126  traits_type::assign(*__d, __c);
127  else
128  traits_type::assign(__d, __n, __c);
129  }
130 
131  // _S_copy_chars is a separate template to permit specialization
132  // to optimize for the common case of pointers as iterators.
133  template<typename _Iterator>
134  static void
135  _S_copy_chars(_CharT* __p, _Iterator __k1, _Iterator __k2)
136  {
137  for (; __k1 != __k2; ++__k1, ++__p)
138  traits_type::assign(*__p, *__k1); // These types are off.
139  }
140 
141  static void
142  _S_copy_chars(_CharT* __p, __sso_iterator __k1, __sso_iterator __k2)
143  { _S_copy_chars(__p, __k1.base(), __k2.base()); }
144 
145  static void
146  _S_copy_chars(_CharT* __p, __const_sso_iterator __k1,
147  __const_sso_iterator __k2)
148  { _S_copy_chars(__p, __k1.base(), __k2.base()); }
149 
150  static void
151  _S_copy_chars(_CharT* __p, __rc_iterator __k1, __rc_iterator __k2)
152  { _S_copy_chars(__p, __k1.base(), __k2.base()); }
153 
154  static void
155  _S_copy_chars(_CharT* __p, __const_rc_iterator __k1,
156  __const_rc_iterator __k2)
157  { _S_copy_chars(__p, __k1.base(), __k2.base()); }
158 
159  static void
160  _S_copy_chars(_CharT* __p, _CharT* __k1, _CharT* __k2)
161  { _S_copy(__p, __k1, __k2 - __k1); }
162 
163  static void
164  _S_copy_chars(_CharT* __p, const _CharT* __k1, const _CharT* __k2)
165  { _S_copy(__p, __k1, __k2 - __k1); }
166 
167  static int
168  _S_compare(size_type __n1, size_type __n2)
169  {
170  const difference_type __d = difference_type(__n1 - __n2);
171 
172  if (__d > __numeric_traits_integer<int>::__max)
173  return __numeric_traits_integer<int>::__max;
174  else if (__d < __numeric_traits_integer<int>::__min)
175  return __numeric_traits_integer<int>::__min;
176  else
177  return int(__d);
178  }
179  };
180 
181 _GLIBCXX_END_NAMESPACE_VERSION
182 } // namespace
183 
184 #endif /* _VSTRING_UTIL_H */