locale/setlocale.c

   1 /* Copyright (C) 1991, 1992, 1995-2000, 2002, 2003, 2004
   2    Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   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 <alloca.h>
  21 #include <argz.h>
  22 #include <errno.h>
  23 #include <bits/libc-lock.h>
  24 #include <locale.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <unistd.h>
  28
  29 #include "localeinfo.h"
  30
  31 #ifdef NL_CURRENT_INDIRECT
  32
  33 /* For each category declare a special external symbol
  34    _nl_current_CATEGORY_used with a weak reference.
  35    This symbol will is defined in lc-CATEGORY.c and will be linked in
  36    if anything uses _nl_current_CATEGORY (also defined in that module).
  37    Also use a weak reference for the _nl_current_CATEGORY thread variable.  */
  38
  39 # define DEFINE_CATEGORY(category, category_name, items, a) \
  40     extern char _nl_current_##category##_used; \
  41     weak_extern (_nl_current_##category##_used) \
  42     weak_extern (_nl_current_##category)
  43 # include "categories.def"
  44 # undef DEFINE_CATEGORY
  45
  46 /* Now define a table of flags based on those special weak symbols' values.
  47    _nl_current_used[CATEGORY] will be zero if _nl_current_CATEGORY is not
  48    linked in.  */
  49 static char *const _nl_current_used[] =
  50   {
  51 # define DEFINE_CATEGORY(category, category_name, items, a) \
  52     [category] = &_nl_current_##category##_used,
  53 # include "categories.def"
  54 # undef DEFINE_CATEGORY
  55   };
  56
  57 # define CATEGORY_USED(category)        (_nl_current_used[category] != 0)
  58
  59 #else
  60
  61 /* The shared library always loads all the categories,
  62    and the current global settings are kept in _nl_global_locale.  */
  63
  64 # define CATEGORY_USED(category)        (1)
  65
  66 #endif
  67
  68
  69 /* Define an array of category names (also the environment variable names),
  70    indexed by integral category.  */
  71 const char *const _nl_category_names[] =
  72   {
  73 #define DEFINE_CATEGORY(category, category_name, items, a) \
  74     [category] = category_name,
  75 #include "categories.def"
  76 #undef  DEFINE_CATEGORY
  77     [LC_ALL] = "LC_ALL"
  78   };
  79 /* An array of their lengths, for convenience.  */
  80 const size_t _nl_category_name_sizes[] =
  81   {
  82 #define DEFINE_CATEGORY(category, category_name, items, a) \
  83     [category] = sizeof (category_name) - 1,
  84 #include "categories.def"
  85 #undef  DEFINE_CATEGORY
  86     [LC_ALL] = sizeof ("LC_ALL") - 1
  87   };
  88
  89
  90 #ifdef NL_CURRENT_INDIRECT
  91 # define WEAK_POSTLOAD(postload) weak_extern (postload)
  92 #else
  93 # define WEAK_POSTLOAD(postload) /* Need strong refs in static linking.  */
  94 #endif
  95
  96 /* Declare the postload functions used below.  */
  97 #undef  NO_POSTLOAD
  98 #define NO_POSTLOAD _nl_postload_ctype /* Harmless thing known to exist.  */
  99 #define DEFINE_CATEGORY(category, category_name, items, postload) \
 100 extern void postload (void); WEAK_POSTLOAD (postload)
 101 #include "categories.def"
 102 #undef  DEFINE_CATEGORY
 103 #undef  NO_POSTLOAD
 104
 105 /* Define an array indexed by category of postload functions to call after
 106    loading and installing that category's data.  */
 107 static void (*const _nl_category_postload[]) (void) =
 108   {
 109 #define DEFINE_CATEGORY(category, category_name, items, postload) \
 110     [category] = postload,
 111 #include "categories.def"
 112 #undef  DEFINE_CATEGORY
 113   };
 114
 115
 116 /* Lock for protecting global data.  */
 117 __libc_lock_define_initialized (, __libc_setlocale_lock attribute_hidden)
 118
 119 /* Defined in loadmsgcat.c.  */
 120 extern int _nl_msg_cat_cntr;
 121
 122
 123 /* Use this when we come along an error.  */
 124 #define ERROR_RETURN                                                          \
 125   do {                                                                        \
 126     __set_errno (EINVAL);                                                     \
 127     return NULL;                                                              \
 128   } while (0)
 129
 130
 131 /* Construct a new composite name.  */
 132 static char *
 133 new_composite_name (int category, const char *newnames[__LC_LAST])
 134 {
 135   size_t last_len = 0;
 136   size_t cumlen = 0;
 137   int i;
 138   char *new, *p;
 139   int same = 1;
 140
 141   for (i = 0; i < __LC_LAST; ++i)
 142     if (i != LC_ALL)
 143       {
 144         const char *name = (category == LC_ALL ? newnames[i] :
 145                             category == i ? newnames[0] :
 146                             _nl_global_locale.__names[i]);
 147         last_len = strlen (name);
 148         cumlen += _nl_category_name_sizes[i] + 1 + last_len + 1;
 149         if (i > 0 && same && strcmp (name, newnames[0]) != 0)
 150           same = 0;
 151       }
 152
 153   if (same)
 154     {
 155       /* All the categories use the same name.  */
 156       if (strcmp (newnames[0], _nl_C_name) == 0
 157           || strcmp (newnames[0], _nl_POSIX_name) == 0)
 158         return (char *) _nl_C_name;
 159
 160       new = malloc (last_len + 1);
 161
 162       return new == NULL ? NULL : memcpy (new, newnames[0], last_len + 1);
 163     }
 164
 165   new = malloc (cumlen);
 166   if (new == NULL)
 167     return NULL;
 168   p = new;
 169   for (i = 0; i < __LC_LAST; ++i)
 170     if (i != LC_ALL)
 171       {
 172         /* Add "CATEGORY=NAME;" to the string.  */
 173         const char *name = (category == LC_ALL ? newnames[i] :
 174                             category == i ? newnames[0] :
 175                             _nl_global_locale.__names[i]);
 176         p = __stpcpy (p, _nl_category_names[i]);
 177         *p++ = '=';
 178         p = __stpcpy (p, name);
 179         *p++ = ';';
 180       }
 181   p[-1] = '\0';         /* Clobber the last ';'.  */
 182   return new;
 183 }
 184
 185
 186 /* Put NAME in _nl_global_locale.__names.  */
 187 static inline void
 188 setname (int category, const char *name)
 189 {
 190   if (_nl_global_locale.__names[category] == name)
 191     return;
 192
 193   if (_nl_global_locale.__names[category] != _nl_C_name)
 194     free ((char *) _nl_global_locale.__names[category]);
 195
 196   _nl_global_locale.__names[category] = name;
 197 }
 198
 199 /* Put DATA in *_nl_current[CATEGORY].  */
 200 static inline void
 201 setdata (int category, struct locale_data *data)
 202 {
 203   if (CATEGORY_USED (category))
 204     {
 205       _nl_global_locale.__locales[category] = data;
 206       if (_nl_category_postload[category])
 207         (*_nl_category_postload[category]) ();
 208     }
 209 }
 210
 211 char *
 212 setlocale (int category, const char *locale)
 213 {
 214   char *locale_path;
 215   size_t locale_path_len;
 216   const char *locpath_var;
 217   char *composite;
 218
 219   /* Sanity check for CATEGORY argument.  */
 220   if (__builtin_expect (category, 0) < 0
 221       || __builtin_expect (category, 0) >= __LC_LAST)
 222     ERROR_RETURN;
 223
 224   /* Does user want name of current locale?  */
 225   if (locale == NULL)
 226     return (char *) _nl_global_locale.__names[category];
 227
 228   if (strcmp (locale, _nl_global_locale.__names[category]) == 0)
 229     /* Changing to the same thing.  */
 230     return (char *) _nl_global_locale.__names[category];
 231
 232   /* We perhaps really have to load some data.  So we determine the
 233      path in which to look for the data now.  The environment variable
 234      `LOCPATH' must only be used when the binary has no SUID or SGID
 235      bit set.  If using the default path, we tell _nl_find_locale
 236      by passing null and it can check the canonical locale archive.  */
 237   locale_path = NULL;
 238   locale_path_len = 0;
 239
 240   locpath_var = getenv ("LOCPATH");
 241   if (locpath_var != NULL && locpath_var[0] != '\0')
 242     {
 243       if (__argz_create_sep (locpath_var, ':',
 244                              &locale_path, &locale_path_len) != 0)
 245         return NULL;
 246
 247       if (__argz_add_sep (&locale_path, &locale_path_len,
 248                           _nl_default_locale_path, ':') != 0)
 249         return NULL;
 250     }
 251
 252   if (category == LC_ALL)
 253     {
 254       /* The user wants to set all categories.  The desired locales
 255          for the individual categories can be selected by using a
 256          composite locale name.  This is a semi-colon separated list
 257          of entries of the form `CATEGORY=VALUE'.  */
 258       const char *newnames[__LC_LAST];
 259       struct locale_data *newdata[__LC_LAST];
 260
 261       /* Set all name pointers to the argument name.  */
 262       for (category = 0; category < __LC_LAST; ++category)
 263         if (category != LC_ALL)
 264           newnames[category] = (char *) locale;
 265
 266       if (__builtin_expect (strchr (locale, ';') != NULL, 0))
 267         {
 268           /* This is a composite name.  Make a copy and split it up.  */
 269           char *np = strdupa (locale);
 270           char *cp;
 271           int cnt;
 272
 273           while ((cp = strchr (np, '=')) != NULL)
 274             {
 275               for (cnt = 0; cnt < __LC_LAST; ++cnt)
 276                 if (cnt != LC_ALL
 277                     && (size_t) (cp - np) == _nl_category_name_sizes[cnt]
 278                     && memcmp (np, _nl_category_names[cnt], cp - np) == 0)
 279                   break;
 280
 281               if (cnt == __LC_LAST)
 282                 /* Bogus category name.  */
 283                 ERROR_RETURN;
 284
 285               /* Found the category this clause sets.  */
 286               newnames[cnt] = ++cp;
 287               cp = strchr (cp, ';');
 288               if (cp != NULL)
 289                 {
 290                   /* Examine the next clause.  */
 291                   *cp = '\0';
 292                   np = cp + 1;
 293                 }
 294               else
 295                 /* This was the last clause.  We are done.  */
 296                 break;
 297             }
 298
 299           for (cnt = 0; cnt < __LC_LAST; ++cnt)
 300             if (cnt != LC_ALL && newnames[cnt] == locale)
 301               /* The composite name did not specify all categories.  */
 302               ERROR_RETURN;
 303         }
 304
 305       /* Protect global data.  */
 306       __libc_lock_lock (__libc_setlocale_lock);
 307
 308       /* Load the new data for each category.  */
 309       while (category-- > 0)
 310         if (category != LC_ALL)
 311           {
 312             newdata[category] = _nl_find_locale (locale_path, locale_path_len,
 313                                                  category,
 314                                                  &newnames[category]);
 315
 316             if (newdata[category] == NULL)
 317               {
 318 #ifdef NL_CURRENT_INDIRECT
 319                 if (newnames[category] == _nl_C_name)
 320                   /* Null because it's the weak value of _nl_C_LC_FOO.  */
 321                   continue;
 322 #endif
 323                 break;
 324               }
 325
 326             /* We must not simply free a global locale since we have
 327                no control over the usage.  So we mark it as
 328                un-deletable.  And yes, the 'if' is needed, the data
 329                might be in read-only memory.  */
 330             if (newdata[category]->usage_count != UNDELETABLE)
 331               newdata[category]->usage_count = UNDELETABLE;
 332
 333             /* Make a copy of locale name.  */
 334             if (newnames[category] != _nl_C_name)
 335               {
 336                 if (strcmp (newnames[category],
 337                             _nl_global_locale.__names[category]) == 0)
 338                   newnames[category] = _nl_global_locale.__names[category];
 339                 else
 340                   {
 341                     newnames[category] = __strdup (newnames[category]);
 342                     if (newnames[category] == NULL)
 343                       break;
 344                   }
 345               }
 346           }
 347
 348       /* Create new composite name.  */
 349       composite = (category >= 0
 350                    ? NULL : new_composite_name (LC_ALL, newnames));
 351       if (composite != NULL)
 352         {
 353           /* Now we have loaded all the new data.  Put it in place.  */
 354           for (category = 0; category < __LC_LAST; ++category)
 355             if (category != LC_ALL)
 356               {
 357                 setdata (category, newdata[category]);
 358                 setname (category, newnames[category]);
 359               }
 360           setname (LC_ALL, composite);
 361
 362           /* We successfully loaded a new locale.  Let the message catalog
 363              functions know about this.  */
 364           ++_nl_msg_cat_cntr;
 365         }
 366       else
 367         for (++category; category < __LC_LAST; ++category)
 368           if (category != LC_ALL && newnames[category] != _nl_C_name
 369               && newnames[category] != _nl_global_locale.__names[category])
 370             free ((char *) newnames[category]);
 371
 372       /* Critical section left.  */
 373       __libc_lock_unlock (__libc_setlocale_lock);
 374
 375       /* Free the resources (the locale path variable).  */
 376       free (locale_path);
 377
 378       return composite;
 379     }
 380   else
 381     {
 382       struct locale_data *newdata = NULL;
 383       const char *newname[1] = { locale };
 384
 385       /* Protect global data.  */
 386       __libc_lock_lock (__libc_setlocale_lock);
 387
 388       if (CATEGORY_USED (category))
 389         {
 390           /* Only actually load the data if anything will use it.  */
 391           newdata = _nl_find_locale (locale_path, locale_path_len, category,
 392                                      &newname[0]);
 393           if (newdata == NULL)
 394             goto abort_single;
 395
 396           /* We must not simply free a global locale since we have no
 397              control over the usage.  So we mark it as un-deletable.
 398
 399              Note: do not remove the `if', it's necessary to copy with
 400              the builtin locale data.  */
 401           if (newdata->usage_count != UNDELETABLE)
 402             newdata->usage_count = UNDELETABLE;
 403         }
 404
 405       /* Make a copy of locale name.  */
 406       if (newname[0] != _nl_C_name)
 407         {
 408           newname[0] = __strdup (newname[0]);
 409           if (newname[0] == NULL)
 410             goto abort_single;
 411         }
 412
 413       /* Create new composite name.  */
 414       composite = new_composite_name (category, newname);
 415       if (composite == NULL)
 416         {
 417           if (newname[0] != _nl_C_name)
 418             free ((char *) newname[0]);
 419
 420           /* Say that we don't have any data loaded.  */
 421         abort_single:
 422           newname[0] = NULL;
 423         }
 424       else
 425         {
 426           if (CATEGORY_USED (category))
 427             setdata (category, newdata);
 428
 429           setname (category, newname[0]);
 430           setname (LC_ALL, composite);
 431
 432           /* We successfully loaded a new locale.  Let the message catalog
 433              functions know about this.  */
 434           ++_nl_msg_cat_cntr;
 435         }
 436
 437       /* Critical section left.  */
 438       __libc_lock_unlock (__libc_setlocale_lock);
 439
 440       /* Free the resources (the locale path variable.  */
 441       free (locale_path);
 442
 443       return (char *) newname[0];
 444     }
 445 }
 446 libc_hidden_def (setlocale)
 447
 448 static void __libc_freeres_fn_section
 449 free_category (int category,
 450                struct locale_data *here, struct locale_data *c_data)
 451 {
 452   struct loaded_l10nfile *runp = _nl_locale_file_list[category];
 453
 454   /* If this category is already "C" don't do anything.  */
 455   if (here != c_data)
 456     {
 457       /* We have to be prepared that sometime later we still
 458          might need the locale information.  */
 459       setdata (category, c_data);
 460       setname (category, _nl_C_name);
 461     }
 462
 463   while (runp != NULL)
 464     {
 465       struct loaded_l10nfile *curr = runp;
 466       struct locale_data *data = (struct locale_data *) runp->data;
 467
 468       if (data != NULL && data != c_data)
 469         _nl_unload_locale (data);
 470       runp = runp->next;
 471       free ((char *) curr->filename);
 472       free (curr);
 473     }
 474 }
 475
 476 /* This is called from iconv/gconv_db.c's free_mem, as locales must
 477    be freed before freeing gconv steps arrays.  */
 478 void __libc_freeres_fn_section
 479 _nl_locale_subfreeres (void)
 480 {
 481 #ifdef NL_CURRENT_INDIRECT
 482   /* We don't use the loop because we want to have individual weak
 483      symbol references here.  */
 484 # define DEFINE_CATEGORY(category, category_name, items, a)                   \
 485   if (CATEGORY_USED (category))                                               \
 486     {                                                                         \
 487       extern struct locale_data _nl_C_##category;                             \
 488       weak_extern (_nl_C_##category)                                          \
 489       free_category (category, *_nl_current_##category, &_nl_C_##category);   \
 490     }
 491 # include "categories.def"
 492 # undef DEFINE_CATEGORY
 493 #else
 494   int category;
 495
 496   for (category = 0; category < __LC_LAST; ++category)
 497     if (category != LC_ALL)
 498       free_category (category, _NL_CURRENT_DATA (category),
 499                      _nl_C_locobj.__locales[category]);
 500 #endif
 501
 502   setname (LC_ALL, _nl_C_name);
 503
 504   /* This frees the data structures associated with the locale archive.
 505      The locales from the archive are not in the file list, so we have
 506      not called _nl_unload_locale on them above.  */
 507   _nl_archive_subfreeres ();
 508 }