1 /* Copyright (C) 1991-2022 Free Software Foundation, Inc.
2    This file is part of the GNU C Library.
3 
4    The GNU C Library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the License, or (at your option) any later version.
8 
9    The GNU C Library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library; if not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include <alloca.h>
19 #include <argz.h>
20 #include <errno.h>
21 #include <libc-lock.h>
22 #include <locale.h>
23 #include <stdlib.h>
24 #include <string.h>
25 #include <unistd.h>
26 
27 #include "localeinfo.h"
28 
29 #ifdef NL_CURRENT_INDIRECT
30 
31 /* For each category declare a special external symbol
32    _nl_current_CATEGORY_used with a weak reference.
33    This symbol will is defined in lc-CATEGORY.c and will be linked in
34    if anything uses _nl_current_CATEGORY (also defined in that module).
35    Also use a weak reference for the _nl_current_CATEGORY thread variable.  */
36 
37 # define DEFINE_CATEGORY(category, category_name, items, a) \
38     extern char _nl_current_##category##_used; \
39     weak_extern (_nl_current_##category##_used) \
40     weak_extern (_nl_current_##category)
41 # include "categories.def"
42 # undef	DEFINE_CATEGORY
43 
44 /* Now define a table of flags based on those special weak symbols' values.
45    _nl_current_used[CATEGORY] will be zero if _nl_current_CATEGORY is not
46    linked in.  */
47 static char *const _nl_current_used[] =
48   {
49 # define DEFINE_CATEGORY(category, category_name, items, a) \
50     [category] = &_nl_current_##category##_used,
51 # include "categories.def"
52 # undef	DEFINE_CATEGORY
53   };
54 
55 # define CATEGORY_USED(category)	(_nl_current_used[category] != 0)
56 
57 #else
58 
59 /* The shared library always loads all the categories,
60    and the current global settings are kept in _nl_global_locale.  */
61 
62 # define CATEGORY_USED(category)	(1)
63 
64 #endif
65 
66 
67 /* Define an array of category names (also the environment variable names).  */
68 const struct catnamestr_t _nl_category_names attribute_hidden =
69   {
70 #define DEFINE_CATEGORY(category, category_name, items, a) \
71     category_name,
72 #include "categories.def"
73 #undef DEFINE_CATEGORY
74   };
75 
76 const uint8_t _nl_category_name_idxs[__LC_LAST] attribute_hidden =
77   {
78 #define DEFINE_CATEGORY(category, category_name, items, a) \
79     [category] = offsetof (struct catnamestr_t, CATNAMEMF (__LINE__)),
80 #include "categories.def"
81 #undef DEFINE_CATEGORY
82   };
83 
84 /* An array of their lengths, for convenience.  */
85 const uint8_t _nl_category_name_sizes[] attribute_hidden =
86   {
87 #define DEFINE_CATEGORY(category, category_name, items, a) \
88     [category] = sizeof (category_name) - 1,
89 #include "categories.def"
90 #undef	DEFINE_CATEGORY
91     [LC_ALL] = sizeof ("LC_ALL") - 1
92   };
93 
94 
95 #ifdef NL_CURRENT_INDIRECT
96 # define WEAK_POSTLOAD(postload) weak_extern (postload)
97 #else
98 # define WEAK_POSTLOAD(postload) /* Need strong refs in static linking.  */
99 #endif
100 
101 /* Declare the postload functions used below.  */
102 #undef	NO_POSTLOAD
103 #define NO_POSTLOAD _nl_postload_ctype /* Harmless thing known to exist.  */
104 #define DEFINE_CATEGORY(category, category_name, items, postload) \
105 extern void postload (void); WEAK_POSTLOAD (postload)
106 #include "categories.def"
107 #undef	DEFINE_CATEGORY
108 #undef	NO_POSTLOAD
109 
110 /* Define an array indexed by category of postload functions to call after
111    loading and installing that category's data.  */
112 static void (*const _nl_category_postload[]) (void) =
113   {
114 #define DEFINE_CATEGORY(category, category_name, items, postload) \
115     [category] = postload,
116 #include "categories.def"
117 #undef	DEFINE_CATEGORY
118   };
119 
120 
121 /* Lock for protecting global data.  */
122 __libc_rwlock_define_initialized (, __libc_setlocale_lock attribute_hidden)
123 
124 /* Defined in loadmsgcat.c.  */
125 extern int _nl_msg_cat_cntr;
126 
127 
128 /* Use this when we come along an error.  */
129 #define ERROR_RETURN							      \
130   do {									      \
131     __set_errno (EINVAL);						      \
132     return NULL;							      \
133   } while (0)
134 
135 
136 /* Construct a new composite name.  */
137 static char *
new_composite_name(int category,const char ** newnames)138 new_composite_name (int category, const char **newnames)
139 {
140   size_t last_len = 0;
141   size_t cumlen = 0;
142   int i;
143   char *new, *p;
144   int same = 1;
145 
146   for (i = 0; i < __LC_LAST; ++i)
147     if (i != LC_ALL)
148       {
149 	const char *name = (category == LC_ALL ? newnames[i]
150 			    : category == i ? newnames[0]
151 			    : _nl_global_locale.__names[i]);
152 	last_len = strlen (name);
153 	cumlen += _nl_category_name_sizes[i] + 1 + last_len + 1;
154 	if (same && name != newnames[0] && strcmp (name, newnames[0]) != 0)
155 	  same = 0;
156       }
157 
158   if (same)
159     {
160       /* All the categories use the same name.  */
161       if (strcmp (newnames[0], _nl_C_name) == 0
162 	  || strcmp (newnames[0], _nl_POSIX_name) == 0)
163 	return (char *) _nl_C_name;
164 
165       new = malloc (last_len + 1);
166 
167       return new == NULL ? NULL : memcpy (new, newnames[0], last_len + 1);
168     }
169 
170   new = malloc (cumlen);
171   if (new == NULL)
172     return NULL;
173   p = new;
174   for (i = 0; i < __LC_LAST; ++i)
175     if (i != LC_ALL)
176       {
177 	/* Add "CATEGORY=NAME;" to the string.  */
178 	const char *name = (category == LC_ALL ? newnames[i]
179 			    : category == i ? newnames[0]
180 			    : _nl_global_locale.__names[i]);
181 	p = __stpcpy (p, _nl_category_names_get (i));
182 	*p++ = '=';
183 	p = __stpcpy (p, name);
184 	*p++ = ';';
185       }
186   p[-1] = '\0';		/* Clobber the last ';'.  */
187   return new;
188 }
189 
190 
191 /* Put NAME in _nl_global_locale.__names.  */
192 static void
setname(int category,const char * name)193 setname (int category, const char *name)
194 {
195   if (_nl_global_locale.__names[category] == name)
196     return;
197 
198   if (_nl_global_locale.__names[category] != _nl_C_name)
199     free ((char *) _nl_global_locale.__names[category]);
200 
201   _nl_global_locale.__names[category] = name;
202 }
203 
204 /* Put DATA in *_nl_current[CATEGORY].  */
205 static void
setdata(int category,struct __locale_data * data)206 setdata (int category, struct __locale_data *data)
207 {
208   if (CATEGORY_USED (category))
209     {
210       _nl_global_locale.__locales[category] = data;
211       if (_nl_category_postload[category])
212 	(*_nl_category_postload[category]) ();
213     }
214 }
215 
216 char *
setlocale(int category,const char * locale)217 setlocale (int category, const char *locale)
218 {
219   char *locale_path;
220   size_t locale_path_len;
221   const char *locpath_var;
222   char *composite;
223 
224   /* Sanity check for CATEGORY argument.  */
225   if (__builtin_expect (category, 0) < 0
226       || __builtin_expect (category, 0) >= __LC_LAST)
227     ERROR_RETURN;
228 
229   /* Does user want name of current locale?  */
230   if (locale == NULL)
231     return (char *) _nl_global_locale.__names[category];
232 
233   /* Protect global data.  */
234   __libc_rwlock_wrlock (__libc_setlocale_lock);
235 
236   if (strcmp (locale, _nl_global_locale.__names[category]) == 0)
237     {
238       /* Changing to the same thing.  */
239       __libc_rwlock_unlock (__libc_setlocale_lock);
240 
241       return (char *) _nl_global_locale.__names[category];
242     }
243 
244   /* We perhaps really have to load some data.  So we determine the
245      path in which to look for the data now.  The environment variable
246      `LOCPATH' must only be used when the binary has no SUID or SGID
247      bit set.  If using the default path, we tell _nl_find_locale
248      by passing null and it can check the canonical locale archive.  */
249   locale_path = NULL;
250   locale_path_len = 0;
251 
252   locpath_var = getenv ("LOCPATH");
253   if (locpath_var != NULL && locpath_var[0] != '\0')
254     {
255       if (__argz_create_sep (locpath_var, ':',
256 			     &locale_path, &locale_path_len) != 0
257 	  || __argz_add_sep (&locale_path, &locale_path_len,
258 			     _nl_default_locale_path, ':') != 0)
259 	{
260 	  __libc_rwlock_unlock (__libc_setlocale_lock);
261 	  return NULL;
262 	}
263     }
264 
265   if (category == LC_ALL)
266     {
267       /* The user wants to set all categories.  The desired locales
268 	 for the individual categories can be selected by using a
269 	 composite locale name.  This is a semi-colon separated list
270 	 of entries of the form `CATEGORY=VALUE'.  */
271       const char *newnames[__LC_LAST];
272       struct __locale_data *newdata[__LC_LAST];
273       /* Copy of the locale argument, for in-place splitting.  */
274       char *locale_copy = NULL;
275 
276       /* Set all name pointers to the argument name.  */
277       for (category = 0; category < __LC_LAST; ++category)
278 	if (category != LC_ALL)
279 	  newnames[category] = (char *) locale;
280 
281       if (__glibc_unlikely (strchr (locale, ';') != NULL))
282 	{
283 	  /* This is a composite name.  Make a copy and split it up.  */
284 	  locale_copy = __strdup (locale);
285 	  if (__glibc_unlikely (locale_copy == NULL))
286 	    {
287 	      __libc_rwlock_unlock (__libc_setlocale_lock);
288 	      return NULL;
289 	    }
290 	  char *np = locale_copy;
291 	  char *cp;
292 	  int cnt;
293 
294 	  while ((cp = strchr (np, '=')) != NULL)
295 	    {
296 	      for (cnt = 0; cnt < __LC_LAST; ++cnt)
297 		if (cnt != LC_ALL
298 		    && (size_t) (cp - np) == _nl_category_name_sizes[cnt]
299 		    && (memcmp (np, (_nl_category_names_get (cnt)), cp - np)
300 			== 0))
301 		  break;
302 
303 	      if (cnt == __LC_LAST)
304 		{
305 		error_return:
306 		  __libc_rwlock_unlock (__libc_setlocale_lock);
307 		  free (locale_copy);
308 
309 		  /* Bogus category name.  */
310 		  ERROR_RETURN;
311 		}
312 
313 	      /* Found the category this clause sets.  */
314 	      newnames[cnt] = ++cp;
315 	      cp = strchr (cp, ';');
316 	      if (cp != NULL)
317 		{
318 		  /* Examine the next clause.  */
319 		  *cp = '\0';
320 		  np = cp + 1;
321 		}
322 	      else
323 		/* This was the last clause.  We are done.  */
324 		break;
325 	    }
326 
327 	  for (cnt = 0; cnt < __LC_LAST; ++cnt)
328 	    if (cnt != LC_ALL && newnames[cnt] == locale)
329 	      /* The composite name did not specify all categories.  */
330 	      goto error_return;
331 	}
332 
333       /* Load the new data for each category.  */
334       while (category-- > 0)
335 	if (category != LC_ALL)
336 	  {
337 	    newdata[category] = _nl_find_locale (locale_path, locale_path_len,
338 						 category,
339 						 &newnames[category]);
340 
341 	    if (newdata[category] == NULL)
342 	      {
343 #ifdef NL_CURRENT_INDIRECT
344 		if (newnames[category] == _nl_C_name)
345 		  /* Null because it's the weak value of _nl_C_LC_FOO.  */
346 		  continue;
347 #endif
348 		break;
349 	      }
350 
351 	    /* We must not simply free a global locale since we have
352 	       no control over the usage.  So we mark it as
353 	       un-deletable.  And yes, the 'if' is needed, the data
354 	       might be in read-only memory.  */
355 	    if (newdata[category]->usage_count != UNDELETABLE)
356 	      newdata[category]->usage_count = UNDELETABLE;
357 
358 	    /* Make a copy of locale name.  */
359 	    if (newnames[category] != _nl_C_name)
360 	      {
361 		if (strcmp (newnames[category],
362 			    _nl_global_locale.__names[category]) == 0)
363 		  newnames[category] = _nl_global_locale.__names[category];
364 		else
365 		  {
366 		    newnames[category] = __strdup (newnames[category]);
367 		    if (newnames[category] == NULL)
368 		      break;
369 		  }
370 	      }
371 	  }
372 
373       /* Create new composite name.  */
374       composite = (category >= 0
375 		   ? NULL : new_composite_name (LC_ALL, newnames));
376       if (composite != NULL)
377 	{
378 	  /* Now we have loaded all the new data.  Put it in place.  */
379 	  for (category = 0; category < __LC_LAST; ++category)
380 	    if (category != LC_ALL)
381 	      {
382 		setdata (category, newdata[category]);
383 		setname (category, newnames[category]);
384 	      }
385 	  setname (LC_ALL, composite);
386 
387 	  /* We successfully loaded a new locale.  Let the message catalog
388 	     functions know about this.  */
389 	  ++_nl_msg_cat_cntr;
390 	}
391       else
392 	for (++category; category < __LC_LAST; ++category)
393 	  if (category != LC_ALL && newnames[category] != _nl_C_name
394 	      && newnames[category] != _nl_global_locale.__names[category])
395 	    free ((char *) newnames[category]);
396 
397       /* Critical section left.  */
398       __libc_rwlock_unlock (__libc_setlocale_lock);
399 
400       /* Free the resources.  */
401       free (locale_path);
402       free (locale_copy);
403 
404       return composite;
405     }
406   else
407     {
408       struct __locale_data *newdata = NULL;
409       const char *newname[1] = { locale };
410 
411       if (CATEGORY_USED (category))
412 	{
413 	  /* Only actually load the data if anything will use it.  */
414 	  newdata = _nl_find_locale (locale_path, locale_path_len, category,
415 				     &newname[0]);
416 	  if (newdata == NULL)
417 	    goto abort_single;
418 
419 	  /* We must not simply free a global locale since we have no
420 	     control over the usage.  So we mark it as un-deletable.
421 
422 	     Note: do not remove the `if', it's necessary to cope with
423 	     the builtin locale data.  */
424 	  if (newdata->usage_count != UNDELETABLE)
425 	    newdata->usage_count = UNDELETABLE;
426 	}
427 
428       /* Make a copy of locale name.  */
429       if (newname[0] != _nl_C_name)
430 	{
431 	  newname[0] = __strdup (newname[0]);
432 	  if (newname[0] == NULL)
433 	    goto abort_single;
434 	}
435 
436       /* Create new composite name.  */
437       composite = new_composite_name (category, newname);
438       if (composite == NULL)
439 	{
440 	  if (newname[0] != _nl_C_name)
441 	    free ((char *) newname[0]);
442 
443 	  /* Say that we don't have any data loaded.  */
444 	abort_single:
445 	  newname[0] = NULL;
446 	}
447       else
448 	{
449 	  if (CATEGORY_USED (category))
450 	    setdata (category, newdata);
451 
452 	  setname (category, newname[0]);
453 	  setname (LC_ALL, composite);
454 
455 	  /* We successfully loaded a new locale.  Let the message catalog
456 	     functions know about this.  */
457 	  ++_nl_msg_cat_cntr;
458 	}
459 
460       /* Critical section left.  */
461       __libc_rwlock_unlock (__libc_setlocale_lock);
462 
463       /* Free the resources (the locale path variable.  */
464       free (locale_path);
465 
466       return (char *) newname[0];
467     }
468 }
libc_hidden_def(setlocale)469 libc_hidden_def (setlocale)
470 
471 static void __libc_freeres_fn_section
472 free_category (int category,
473 	       struct __locale_data *here, struct __locale_data *c_data)
474 {
475   struct loaded_l10nfile *runp = _nl_locale_file_list[category];
476 
477   /* If this category is already "C" don't do anything.  */
478   if (here != c_data)
479     {
480       /* We have to be prepared that sometime later we still
481 	 might need the locale information.  */
482       setdata (category, c_data);
483       setname (category, _nl_C_name);
484     }
485 
486   while (runp != NULL)
487     {
488       struct loaded_l10nfile *curr = runp;
489       struct __locale_data *data = (struct __locale_data *) runp->data;
490 
491       if (data != NULL && data != c_data)
492 	_nl_unload_locale (category, data);
493       runp = runp->next;
494       free ((char *) curr->filename);
495       free (curr);
496     }
497 }
498 
499 /* This is called from iconv/gconv_db.c's free_mem, as locales must
500    be freed before freeing gconv steps arrays.  */
501 void __libc_freeres_fn_section
_nl_locale_subfreeres(void)502 _nl_locale_subfreeres (void)
503 {
504 #ifdef NL_CURRENT_INDIRECT
505   /* We don't use the loop because we want to have individual weak
506      symbol references here.  */
507 # define DEFINE_CATEGORY(category, category_name, items, a)		      \
508   if (CATEGORY_USED (category))						      \
509     {									      \
510       extern struct __locale_data _nl_C_##category;			      \
511       weak_extern (_nl_C_##category)					      \
512       free_category (category, *_nl_current_##category, &_nl_C_##category);   \
513     }
514 # include "categories.def"
515 # undef	DEFINE_CATEGORY
516 #else
517   int category;
518 
519   for (category = 0; category < __LC_LAST; ++category)
520     if (category != LC_ALL)
521       free_category (category, _NL_CURRENT_DATA (category),
522 		     _nl_C_locobj.__locales[category]);
523 #endif
524 
525   setname (LC_ALL, _nl_C_name);
526 
527   /* This frees the data structures associated with the locale archive.
528      The locales from the archive are not in the file list, so we have
529      not called _nl_unload_locale on them above.  */
530   _nl_archive_subfreeres ();
531 }
532