libstdc++
vstring_util.h
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1 // Versatile string utility -*- C++ -*-
2 
3 // Copyright (C) 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10 
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15 
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19 
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24 
25 /** @file ext/vstring_util.h
26  * This file is a GNU extension to the Standard C++ Library.
27  * This is an internal header file, included by other library headers.
28  * You should not attempt to use it directly.
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 
46 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
47 
48  template<typename _CharT, typename _Traits, typename _Alloc>
49  struct __vstring_utility
50  {
51  typedef typename _Alloc::template rebind<_CharT>::other _CharT_alloc_type;
52 
53  typedef _Traits traits_type;
54  typedef typename _Traits::char_type value_type;
55  typedef typename _CharT_alloc_type::size_type size_type;
56  typedef typename _CharT_alloc_type::difference_type difference_type;
57  typedef typename _CharT_alloc_type::pointer pointer;
58  typedef typename _CharT_alloc_type::const_pointer const_pointer;
59 
60  // For __sso_string.
61  typedef __gnu_cxx::
62  __normal_iterator<pointer, __gnu_cxx::
63  __versa_string<_CharT, _Traits, _Alloc,
64  __sso_string_base> >
65  __sso_iterator;
66  typedef __gnu_cxx::
67  __normal_iterator<const_pointer, __gnu_cxx::
68  __versa_string<_CharT, _Traits, _Alloc,
69  __sso_string_base> >
70  __const_sso_iterator;
71 
72  // For __rc_string.
73  typedef __gnu_cxx::
74  __normal_iterator<pointer, __gnu_cxx::
75  __versa_string<_CharT, _Traits, _Alloc,
76  __rc_string_base> >
77  __rc_iterator;
78  typedef __gnu_cxx::
79  __normal_iterator<const_pointer, __gnu_cxx::
80  __versa_string<_CharT, _Traits, _Alloc,
81  __rc_string_base> >
82  __const_rc_iterator;
83 
84  // NB: When the allocator is empty, deriving from it saves space
85  // (http://www.cantrip.org/emptyopt.html).
86  template<typename _Alloc1>
87  struct _Alloc_hider
88  : public _Alloc1
89  {
90  _Alloc_hider(_CharT* __ptr)
91  : _Alloc1(), _M_p(__ptr) { }
92 
93  _Alloc_hider(const _Alloc1& __a, _CharT* __ptr)
94  : _Alloc1(__a), _M_p(__ptr) { }
95 
96  _CharT* _M_p; // The actual data.
97  };
98 
99  // When __n = 1 way faster than the general multichar
100  // traits_type::copy/move/assign.
101  static void
102  _S_copy(_CharT* __d, const _CharT* __s, size_type __n)
103  {
104  if (__n == 1)
105  traits_type::assign(*__d, *__s);
106  else
107  traits_type::copy(__d, __s, __n);
108  }
109 
110  static void
111  _S_move(_CharT* __d, const _CharT* __s, size_type __n)
112  {
113  if (__n == 1)
114  traits_type::assign(*__d, *__s);
115  else
116  traits_type::move(__d, __s, __n);
117  }
118 
119  static void
120  _S_assign(_CharT* __d, size_type __n, _CharT __c)
121  {
122  if (__n == 1)
123  traits_type::assign(*__d, __c);
124  else
125  traits_type::assign(__d, __n, __c);
126  }
127 
128  // _S_copy_chars is a separate template to permit specialization
129  // to optimize for the common case of pointers as iterators.
130  template<typename _Iterator>
131  static void
132  _S_copy_chars(_CharT* __p, _Iterator __k1, _Iterator __k2)
133  {
134  for (; __k1 != __k2; ++__k1, ++__p)
135  traits_type::assign(*__p, *__k1); // These types are off.
136  }
137 
138  static void
139  _S_copy_chars(_CharT* __p, __sso_iterator __k1, __sso_iterator __k2)
140  { _S_copy_chars(__p, __k1.base(), __k2.base()); }
141 
142  static void
143  _S_copy_chars(_CharT* __p, __const_sso_iterator __k1,
144  __const_sso_iterator __k2)
145  { _S_copy_chars(__p, __k1.base(), __k2.base()); }
146 
147  static void
148  _S_copy_chars(_CharT* __p, __rc_iterator __k1, __rc_iterator __k2)
149  { _S_copy_chars(__p, __k1.base(), __k2.base()); }
150 
151  static void
152  _S_copy_chars(_CharT* __p, __const_rc_iterator __k1,
153  __const_rc_iterator __k2)
154  { _S_copy_chars(__p, __k1.base(), __k2.base()); }
155 
156  static void
157  _S_copy_chars(_CharT* __p, _CharT* __k1, _CharT* __k2)
158  { _S_copy(__p, __k1, __k2 - __k1); }
159 
160  static void
161  _S_copy_chars(_CharT* __p, const _CharT* __k1, const _CharT* __k2)
162  { _S_copy(__p, __k1, __k2 - __k1); }
163 
164  static int
165  _S_compare(size_type __n1, size_type __n2)
166  {
167  const difference_type __d = difference_type(__n1 - __n2);
168 
169  if (__d > __numeric_traits_integer<int>::__max)
170  return __numeric_traits_integer<int>::__max;
171  else if (__d < __numeric_traits_integer<int>::__min)
172  return __numeric_traits_integer<int>::__min;
173  else
174  return int(__d);
175  }
176  };
177 
178 _GLIBCXX_END_NAMESPACE
179 
180 #endif /* _VSTRING_UTIL_H */
Managing sequences of characters and character-like objects.
Definition: vstring.h:49