1 // Locale support -*- C++ -*-
2 
3 // Copyright (C) 2007, 2008, 2009, 2010, 2011 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 bits/locale_classes.tcc
26  *  This is an internal header file, included by other library headers.
27  *  Do not attempt to use it directly. @headername{locale}
28  */
29 
30 //
31 // ISO C++ 14882: 22.1  Locales
32 //
33 
34 #ifndef _LOCALE_CLASSES_TCC
35 #define _LOCALE_CLASSES_TCC 1
36 
37 #pragma GCC system_header
38 
39 namespace std _GLIBCXX_VISIBILITY(default)
40 {
41 _GLIBCXX_BEGIN_NAMESPACE_VERSION
42 
43   template<typename _Facet>
44     locale::
45     locale(const locale& __other, _Facet* __f)
46     {
47       _M_impl = new _Impl(*__other._M_impl, 1);
48 
49       __try
50 	{ _M_impl->_M_install_facet(&_Facet::id, __f); }
51       __catch(...)
52 	{
53 	  _M_impl->_M_remove_reference();
54 	  __throw_exception_again;
55 	}
56       delete [] _M_impl->_M_names[0];
57       _M_impl->_M_names[0] = 0;   // Unnamed.
58     }
59 
60   template<typename _Facet>
61     locale
62     locale::
63     combine(const locale& __other) const
64     {
65       _Impl* __tmp = new _Impl(*_M_impl, 1);
66       __try
67 	{
68 	  __tmp->_M_replace_facet(__other._M_impl, &_Facet::id);
69 	}
70       __catch(...)
71 	{
72 	  __tmp->_M_remove_reference();
73 	  __throw_exception_again;
74 	}
75       return locale(__tmp);
76     }
77 
78   template<typename _CharT, typename _Traits, typename _Alloc>
79     bool
80     locale::
81     operator()(const basic_string<_CharT, _Traits, _Alloc>& __s1,
82 	       const basic_string<_CharT, _Traits, _Alloc>& __s2) const
83     {
84       typedef std::collate<_CharT> __collate_type;
85       const __collate_type& __collate = use_facet<__collate_type>(*this);
86       return (__collate.compare(__s1.data(), __s1.data() + __s1.length(),
87 				__s2.data(), __s2.data() + __s2.length()) < 0);
88     }
89 
90   /**
91    *  @brief  Test for the presence of a facet.
92    *
93    *  has_facet tests the locale argument for the presence of the facet type
94    *  provided as the template parameter.  Facets derived from the facet
95    *  parameter will also return true.
96    *
97    *  @tparam  _Facet  The facet type to test the presence of.
98    *  @param  __loc  The locale to test.
99    *  @return  true if @p __loc contains a facet of type _Facet, else false.
100   */
101   template<typename _Facet>
102     bool
103     has_facet(const locale& __loc) throw()
104     {
105       const size_t __i = _Facet::id._M_id();
106       const locale::facet** __facets = __loc._M_impl->_M_facets;
107       return (__i < __loc._M_impl->_M_facets_size
108 #ifdef __GXX_RTTI
109 	      && dynamic_cast<const _Facet*>(__facets[__i]));
110 #else
111               && static_cast<const _Facet*>(__facets[__i]));
112 #endif
113     }
114 
115   /**
116    *  @brief  Return a facet.
117    *
118    *  use_facet looks for and returns a reference to a facet of type Facet
119    *  where Facet is the template parameter.  If has_facet(locale) is true,
120    *  there is a suitable facet to return.  It throws std::bad_cast if the
121    *  locale doesn't contain a facet of type Facet.
122    *
123    *  @tparam  _Facet  The facet type to access.
124    *  @param  __loc  The locale to use.
125    *  @return  Reference to facet of type Facet.
126    *  @throw  std::bad_cast if @p __loc doesn't contain a facet of type _Facet.
127   */
128   template<typename _Facet>
129     const _Facet&
130     use_facet(const locale& __loc)
131     {
132       const size_t __i = _Facet::id._M_id();
133       const locale::facet** __facets = __loc._M_impl->_M_facets;
134       if (__i >= __loc._M_impl->_M_facets_size || !__facets[__i])
135         __throw_bad_cast();
136 #ifdef __GXX_RTTI
137       return dynamic_cast<const _Facet&>(*__facets[__i]);
138 #else
139       return static_cast<const _Facet&>(*__facets[__i]);
140 #endif
141     }
142 
143 
144   // Generic version does nothing.
145   template<typename _CharT>
146     int
147     collate<_CharT>::_M_compare(const _CharT*, const _CharT*) const throw ()
148     { return 0; }
149 
150   // Generic version does nothing.
151   template<typename _CharT>
152     size_t
153     collate<_CharT>::_M_transform(_CharT*, const _CharT*, size_t) const throw ()
154     { return 0; }
155 
156   template<typename _CharT>
157     int
158     collate<_CharT>::
159     do_compare(const _CharT* __lo1, const _CharT* __hi1,
160 	       const _CharT* __lo2, const _CharT* __hi2) const
161     {
162       // strcoll assumes zero-terminated strings so we make a copy
163       // and then put a zero at the end.
164       const string_type __one(__lo1, __hi1);
165       const string_type __two(__lo2, __hi2);
166 
167       const _CharT* __p = __one.c_str();
168       const _CharT* __pend = __one.data() + __one.length();
169       const _CharT* __q = __two.c_str();
170       const _CharT* __qend = __two.data() + __two.length();
171 
172       // strcoll stops when it sees a nul character so we break
173       // the strings into zero-terminated substrings and pass those
174       // to strcoll.
175       for (;;)
176 	{
177 	  const int __res = _M_compare(__p, __q);
178 	  if (__res)
179 	    return __res;
180 
181 	  __p += char_traits<_CharT>::length(__p);
182 	  __q += char_traits<_CharT>::length(__q);
183 	  if (__p == __pend && __q == __qend)
184 	    return 0;
185 	  else if (__p == __pend)
186 	    return -1;
187 	  else if (__q == __qend)
188 	    return 1;
189 
190 	  __p++;
191 	  __q++;
192 	}
193     }
194 
195   template<typename _CharT>
196     typename collate<_CharT>::string_type
197     collate<_CharT>::
198     do_transform(const _CharT* __lo, const _CharT* __hi) const
199     {
200       string_type __ret;
201 
202       // strxfrm assumes zero-terminated strings so we make a copy
203       const string_type __str(__lo, __hi);
204 
205       const _CharT* __p = __str.c_str();
206       const _CharT* __pend = __str.data() + __str.length();
207 
208       size_t __len = (__hi - __lo) * 2;
209 
210       _CharT* __c = new _CharT[__len];
211 
212       __try
213 	{
214 	  // strxfrm stops when it sees a nul character so we break
215 	  // the string into zero-terminated substrings and pass those
216 	  // to strxfrm.
217 	  for (;;)
218 	    {
219 	      // First try a buffer perhaps big enough.
220 	      size_t __res = _M_transform(__c, __p, __len);
221 	      // If the buffer was not large enough, try again with the
222 	      // correct size.
223 	      if (__res >= __len)
224 		{
225 		  __len = __res + 1;
226 		  delete [] __c, __c = 0;
227 		  __c = new _CharT[__len];
228 		  __res = _M_transform(__c, __p, __len);
229 		}
230 
231 	      __ret.append(__c, __res);
232 	      __p += char_traits<_CharT>::length(__p);
233 	      if (__p == __pend)
234 		break;
235 
236 	      __p++;
237 	      __ret.push_back(_CharT());
238 	    }
239 	}
240       __catch(...)
241 	{
242 	  delete [] __c;
243 	  __throw_exception_again;
244 	}
245 
246       delete [] __c;
247 
248       return __ret;
249     }
250 
251   template<typename _CharT>
252     long
253     collate<_CharT>::
254     do_hash(const _CharT* __lo, const _CharT* __hi) const
255     {
256       unsigned long __val = 0;
257       for (; __lo < __hi; ++__lo)
258 	__val =
259 	  *__lo + ((__val << 7)
260 		   | (__val >> (__gnu_cxx::__numeric_traits<unsigned long>::
261 				__digits - 7)));
262       return static_cast<long>(__val);
263     }
264 
265   // Inhibit implicit instantiations for required instantiations,
266   // which are defined via explicit instantiations elsewhere.
267 #if _GLIBCXX_EXTERN_TEMPLATE
268   extern template class collate<char>;
269   extern template class collate_byname<char>;
270 
271   extern template
272     const collate<char>&
273     use_facet<collate<char> >(const locale&);
274 
275   extern template
276     bool
277     has_facet<collate<char> >(const locale&);
278 
279 #ifdef _GLIBCXX_USE_WCHAR_T
280   extern template class collate<wchar_t>;
281   extern template class collate_byname<wchar_t>;
282 
283   extern template
284     const collate<wchar_t>&
285     use_facet<collate<wchar_t> >(const locale&);
286 
287   extern template
288     bool
289     has_facet<collate<wchar_t> >(const locale&);
290 #endif
291 #endif
292 
293 _GLIBCXX_END_NAMESPACE_VERSION
294 } // namespace std
295 
296 #endif
297