xref: /haiku/src/system/libroot/posix/glibc/wcsmbs/wcsmbsload.c (revision 239222b2369c39dc52df52b0a7cdd6cc0a91bc92)
1 /* Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
2    This file is part of the GNU C Library.
3    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, write to the Free
17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
18    02111-1307 USA.  */
19 
20 #include <ctype.h>
21 #include <langinfo.h>
22 #include <limits.h>
23 #include <stdlib.h>
24 #include <string.h>
25 
26 #include <locale/localeinfo.h>
27 #include <wcsmbsload.h>
28 #include <bits/libc-lock.h>
29 #include <iconv/gconv_int.h>
30 
31 
32 /* Last loaded locale for LC_CTYPE.  We initialize for the C locale
33    which is enabled at startup.  */
34 extern const struct locale_data _nl_C_LC_CTYPE;
35 const struct locale_data *__wcsmbs_last_locale = &_nl_C_LC_CTYPE;
36 
37 
38 /* These are the descriptions for the default conversion functions.  */
39 static struct __gconv_step to_wc =
40 {
41   .__shlib_handle = NULL,
42   .__modname = NULL,
43   .__counter = INT_MAX,
44   .__from_name = (char *) "ANSI_X3.4-1968//TRANSLIT",
45   .__to_name = (char *) "INTERNAL",
46   .__fct = __gconv_transform_ascii_internal,
47   .__init_fct = NULL,
48   .__end_fct = NULL,
49   .__min_needed_from = 1,
50   .__max_needed_from = 1,
51   .__min_needed_to = 4,
52   .__max_needed_to = 4,
53   .__stateful = 0,
54   .__data = NULL
55 };
56 
57 static struct __gconv_step to_mb =
58 {
59   .__shlib_handle = NULL,
60   .__modname = NULL,
61   .__counter = INT_MAX,
62   .__from_name = (char *) "INTERNAL",
63   .__to_name = (char *) "ANSI_X3.4-1968//TRANSLIT",
64   .__fct = __gconv_transform_internal_ascii,
65   .__init_fct = NULL,
66   .__end_fct = NULL,
67   .__min_needed_from = 4,
68   .__max_needed_from = 4,
69   .__min_needed_to = 1,
70   .__max_needed_to = 1,
71   .__stateful = 0,
72   .__data = NULL
73 };
74 
75 
76 /* For the default locale we only have to handle ANSI_X3.4-1968.  */
77 struct gconv_fcts __wcsmbs_gconv_fcts =
78 {
79   .towc = &to_wc,
80   .towc_nsteps = 1,
81   .tomb = &to_mb,
82   .tomb_nsteps = 1
83 };
84 
85 
86 static inline struct __gconv_step *
87 getfct (const char *to, const char *from, size_t *nstepsp)
88 {
89   size_t nsteps;
90   struct __gconv_step *result;
91 #if 0
92   size_t nstateful;
93   size_t cnt;
94 #endif
95 
96   if (__gconv_find_transform (to, from, &result, &nsteps, 0) != __GCONV_OK)
97     /* Loading the conversion step is not possible.  */
98     return NULL;
99 
100   /* Maybe it is someday necessary to allow more than one step.
101      Currently this is not the case since the conversions handled here
102      are from and to INTERNAL and there always is a converted for
103      that.  It the directly following code is enabled the libio
104      functions will have to allocate appropriate __gconv_step_data
105      elements instead of only one.  */
106 #if 0
107   /* Count the number of stateful conversions.  Since we will only
108      have one 'mbstate_t' object available we can only deal with one
109      stateful conversion.  */
110   nstateful = 0;
111   for (cnt = 0; cnt < nsteps; ++cnt)
112     if (result[cnt].__stateful)
113       ++nstateful;
114   if (nstateful > 1)
115 #else
116   if (nsteps > 1)
117 #endif
118     {
119       /* We cannot handle this case.  */
120       __gconv_close_transform (result, nsteps);
121       result = NULL;
122     }
123   else
124     *nstepsp = nsteps;
125 
126   return result;
127 }
128 
129 
130 /* Extract from the given locale name the character set portion.  Since
131    only the XPG form of the name includes this information we don't have
132    to take care for the CEN form.  */
133 #define extract_charset_name(str) \
134   ({									      \
135     const char *cp = str;						      \
136     char *result = NULL;						      \
137 									      \
138     cp += strcspn (cp, "@.+,");						      \
139     if (*cp == '.')							      \
140       {									      \
141 	const char *endp = ++cp;					      \
142 	while (*endp != '\0' && *endp != '@')				      \
143 	  ++endp;							      \
144 	if (endp != cp)							      \
145 	  result = strndupa (cp, endp - cp);				      \
146       }									      \
147     result;								      \
148   })
149 
150 
151 /* We must modify global data.  */
152 __libc_lock_define_initialized (static, lock)
153 
154 
155 /* Load conversion functions for the currently selected locale.  */
156 void
157 internal_function
158 __wcsmbs_load_conv (const struct locale_data *new_category)
159 {
160   /* Acquire the lock.  */
161   __libc_lock_lock (lock);
162 
163   /* We should repeat the test since while we waited some other thread
164      might have run this function.  */
165   if (__builtin_expect (__wcsmbs_last_locale != new_category, 1))
166     {
167       if (new_category->name == _nl_C_name)	/* Yes, pointer comparison.  */
168 	{
169 	failed:
170 	  __wcsmbs_gconv_fcts.towc = &to_wc;
171 	  __wcsmbs_gconv_fcts.tomb = &to_mb;
172 	}
173       else
174 	{
175 	  /* We must find the real functions.  */
176 	  const char *charset_name;
177 	  const char *complete_name;
178 	  struct __gconv_step *new_towc;
179 	  size_t new_towc_nsteps;
180 	  struct __gconv_step *new_tomb;
181 	  size_t new_tomb_nsteps;
182 	  int use_translit;
183 
184 	  /* Free the old conversions.  */
185 	  if (__wcsmbs_gconv_fcts.tomb != &to_mb)
186 	    __gconv_close_transform (__wcsmbs_gconv_fcts.tomb,
187 				     __wcsmbs_gconv_fcts.tomb_nsteps);
188 	  if (__wcsmbs_gconv_fcts.towc != &to_wc)
189 	    __gconv_close_transform (__wcsmbs_gconv_fcts.towc,
190 				     __wcsmbs_gconv_fcts.towc_nsteps);
191 
192 	  /* Get name of charset of the locale.  */
193 	  charset_name = new_category->values[_NL_ITEM_INDEX(CODESET)].string;
194 
195 	  /* Does the user want transliteration?  */
196 	  use_translit = new_category->use_translit;
197 
198 	  /* Normalize the name and add the slashes necessary for a
199              complete lookup.  */
200 	  complete_name = norm_add_slashes (charset_name,
201 					    use_translit ? "TRANSLIT" : NULL);
202 
203 	  /* It is not necessary to use transliteration in this direction
204 	     since the internal character set is supposed to be able to
205 	     represent all others.  */
206 	  new_towc = getfct ("INTERNAL", complete_name, &new_towc_nsteps);
207 	  new_tomb = (new_towc != NULL
208 		      ? getfct (complete_name, "INTERNAL", &new_tomb_nsteps)
209 		      : NULL);
210 
211 	  /* If any of the conversion functions is not available we don't
212 	     use any since this would mean we cannot convert back and
213 	     forth.*/
214 	  if (new_towc == NULL || new_tomb == NULL)
215 	    {
216 	      if (new_towc != NULL)
217 		__gconv_close_transform (new_towc, 1);
218 
219 	      goto failed;
220 	    }
221 
222 	  __wcsmbs_gconv_fcts.tomb = new_tomb;
223 	  __wcsmbs_gconv_fcts.tomb_nsteps = new_tomb_nsteps;
224 	  __wcsmbs_gconv_fcts.towc = new_towc;
225 	  __wcsmbs_gconv_fcts.towc_nsteps = new_towc_nsteps;
226 	}
227 
228       /* Set last-used variable for current locale.  */
229       __wcsmbs_last_locale = new_category;
230     }
231 
232   __libc_lock_unlock (lock);
233 }
234 
235 
236 /* Clone the current conversion function set.  */
237 void
238 internal_function
239 __wcsmbs_clone_conv (struct gconv_fcts *copy)
240 {
241   /* First make sure the function table is up-to-date.  */
242   update_conversion_ptrs ();
243 
244   /* Make sure the data structures remain the same until we are finished.  */
245   __libc_lock_lock (lock);
246 
247   /* Copy the data.  */
248   *copy = __wcsmbs_gconv_fcts;
249 
250   /* Now increment the usage counters.  */
251   if (copy->towc->__shlib_handle != NULL)
252     ++copy->towc->__counter;
253   if (copy->tomb->__shlib_handle != NULL)
254     ++copy->tomb->__counter;
255 
256   __libc_lock_unlock (lock);
257 }
258 
259 
260 /* Get converters for named charset.  */
261 int
262 internal_function
263 __wcsmbs_named_conv (struct gconv_fcts *copy, const char *name)
264 {
265   copy->towc = getfct ("INTERNAL", name, &copy->towc_nsteps);
266   if (copy->towc != NULL)
267     {
268       copy->tomb = getfct (name, "INTERNAL", &copy->tomb_nsteps);
269       if (copy->tomb == NULL)
270 	__gconv_close_transform (copy->towc, copy->towc_nsteps);
271     }
272 
273   return copy->towc == NULL || copy->tomb == NULL ? 1 : 0;
274 }
275 
276 
277 /* Free all resources if necessary.  */
278 static void __attribute__ ((unused))
279 free_mem (void)
280 {
281   if (__wcsmbs_gconv_fcts.tomb != &to_mb)
282     {
283       struct __gconv_step *old = __wcsmbs_gconv_fcts.tomb;
284       size_t nold = __wcsmbs_gconv_fcts.tomb_nsteps;
285       __wcsmbs_gconv_fcts.tomb = &to_mb;
286       __wcsmbs_gconv_fcts.tomb_nsteps = 1;
287       __gconv_release_cache (old, nold);
288     }
289 
290   if (__wcsmbs_gconv_fcts.towc != &to_wc)
291     {
292       struct __gconv_step *old = __wcsmbs_gconv_fcts.towc;
293       size_t nold = __wcsmbs_gconv_fcts.towc_nsteps;
294       __wcsmbs_gconv_fcts.towc = &to_wc;
295       __wcsmbs_gconv_fcts.towc_nsteps = 1;
296       __gconv_release_cache (old, nold);
297     }
298 }
299 
300 
301 text_set_element (__libc_subfreeres, free_mem);
302