1 // Versatile string utility -*- C++ -*-
2
3 // Copyright (C) 2005-2022 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 is an internal header file, included by other library headers.
27 * Do not attempt to use it directly. @headername{ext/vstring.h}
28 */
29
30 #ifndef _VSTRING_UTIL_H
31 #define _VSTRING_UTIL_H 1
32
33 #pragma GCC system_header
34
35 #include <ext/vstring_fwd.h>
36 #include <debug/debug.h>
37 #include <bits/stl_function.h> // For less
38 #include <bits/functexcept.h>
39 #include <bits/localefwd.h>
40 #include <bits/ostream_insert.h>
41 #include <bits/stl_iterator.h>
42 #include <ext/numeric_traits.h>
43 #include <ext/alloc_traits.h>
44 #include <bits/move.h>
45 #include <bits/range_access.h>
46
_GLIBCXX_VISIBILITY(default)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_traits<_Alloc>::template rebind<_CharT>::other
55 _CharT_alloc_type;
56 typedef __alloc_traits<_CharT_alloc_type> _CharT_alloc_traits;
57
58 typedef _Traits traits_type;
59 typedef typename _Traits::char_type value_type;
60 typedef typename _CharT_alloc_type::size_type size_type;
61 typedef typename _CharT_alloc_type::difference_type difference_type;
62 typedef typename _CharT_alloc_traits::pointer pointer;
63 typedef typename _CharT_alloc_traits::const_pointer const_pointer;
64
65 // For __sso_string.
66 typedef __gnu_cxx::
67 __normal_iterator<pointer, __gnu_cxx::
68 __versa_string<_CharT, _Traits, _Alloc,
69 __sso_string_base> >
70 __sso_iterator;
71 typedef __gnu_cxx::
72 __normal_iterator<const_pointer, __gnu_cxx::
73 __versa_string<_CharT, _Traits, _Alloc,
74 __sso_string_base> >
75 __const_sso_iterator;
76
77 // For __rc_string.
78 typedef __gnu_cxx::
79 __normal_iterator<pointer, __gnu_cxx::
80 __versa_string<_CharT, _Traits, _Alloc,
81 __rc_string_base> >
82 __rc_iterator;
83 typedef __gnu_cxx::
84 __normal_iterator<const_pointer, __gnu_cxx::
85 __versa_string<_CharT, _Traits, _Alloc,
86 __rc_string_base> >
87 __const_rc_iterator;
88
89 // NB: When the allocator is empty, deriving from it saves space
90 // (http://www.cantrip.org/emptyopt.html).
91 template<typename _Alloc1>
92 struct _Alloc_hider
93 : public _Alloc1
94 {
95 _Alloc_hider(_CharT* __ptr)
96 : _Alloc1(), _M_p(__ptr) { }
97
98 _Alloc_hider(const _Alloc1& __a, _CharT* __ptr)
99 : _Alloc1(__a), _M_p(__ptr) { }
100
101 _CharT* _M_p; // The actual data.
102 };
103
104 // When __n = 1 way faster than the general multichar
105 // traits_type::copy/move/assign.
106 static void
107 _S_copy(_CharT* __d, const _CharT* __s, size_type __n)
108 {
109 if (__n == 1)
110 traits_type::assign(*__d, *__s);
111 else
112 traits_type::copy(__d, __s, __n);
113 }
114
115 static void
116 _S_move(_CharT* __d, const _CharT* __s, size_type __n)
117 {
118 if (__n == 1)
119 traits_type::assign(*__d, *__s);
120 else
121 traits_type::move(__d, __s, __n);
122 }
123
124 static void
125 _S_assign(_CharT* __d, size_type __n, _CharT __c)
126 {
127 if (__n == 1)
128 traits_type::assign(*__d, __c);
129 else
130 traits_type::assign(__d, __n, __c);
131 }
132
133 // _S_copy_chars is a separate template to permit specialization
134 // to optimize for the common case of pointers as iterators.
135 template<typename _Iterator>
136 static void
137 _S_copy_chars(_CharT* __p, _Iterator __k1, _Iterator __k2)
138 {
139 for (; __k1 != __k2; ++__k1, ++__p)
140 traits_type::assign(*__p, *__k1); // These types are off.
141 }
142
143 static void
144 _S_copy_chars(_CharT* __p, __sso_iterator __k1, __sso_iterator __k2)
145 { _S_copy_chars(__p, __k1.base(), __k2.base()); }
146
147 static void
148 _S_copy_chars(_CharT* __p, __const_sso_iterator __k1,
149 __const_sso_iterator __k2)
150 { _S_copy_chars(__p, __k1.base(), __k2.base()); }
151
152 static void
153 _S_copy_chars(_CharT* __p, __rc_iterator __k1, __rc_iterator __k2)
154 { _S_copy_chars(__p, __k1.base(), __k2.base()); }
155
156 static void
157 _S_copy_chars(_CharT* __p, __const_rc_iterator __k1,
158 __const_rc_iterator __k2)
159 { _S_copy_chars(__p, __k1.base(), __k2.base()); }
160
161 static void
162 _S_copy_chars(_CharT* __p, _CharT* __k1, _CharT* __k2)
163 { _S_copy(__p, __k1, __k2 - __k1); }
164
165 static void
166 _S_copy_chars(_CharT* __p, const _CharT* __k1, const _CharT* __k2)
167 { _S_copy(__p, __k1, __k2 - __k1); }
168
169 static int
170 _S_compare(size_type __n1, size_type __n2)
171 {
172 const difference_type __d = difference_type(__n1 - __n2);
173
174 if (__d > __numeric_traits_integer<int>::__max)
175 return __numeric_traits_integer<int>::__max;
176 else if (__d < __numeric_traits_integer<int>::__min)
177 return __numeric_traits_integer<int>::__min;
178 else
179 return int(__d);
180 }
181 };
182
183 _GLIBCXX_END_NAMESPACE_VERSION
184 } // namespace
185
186 #endif /* _VSTRING_UTIL_H */
187