locale/setlocale.c

   1 /* Copyright (C) 1991-2013 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    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <alloca.h>
  19 #include <argz.h>
  20 #include <errno.h>
  21 #include <bits/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 union catnamestr_t _nl_category_names attribute_hidden =
  69   {
  70     {
  71 #define DEFINE_CATEGORY(category, category_name, items, a) \
  72       category_name,
  73 #include "categories.def"
  74 #undef DEFINE_CATEGORY
  75     }
  76   };
  77
  78 const uint8_t _nl_category_name_idxs[__LC_LAST] attribute_hidden =
  79   {
  80 #define DEFINE_CATEGORY(category, category_name, items, a) \
  81     [category] = offsetof (union catnamestr_t, CATNAMEMF (__LINE__)),
  82 #include "categories.def"
  83 #undef DEFINE_CATEGORY
  84   };
  85
  86 /* An array of their lengths, for convenience.  */
  87 const uint8_t _nl_category_name_sizes[] attribute_hidden =
  88   {
  89 #define DEFINE_CATEGORY(category, category_name, items, a) \
  90     [category] = sizeof (category_name) - 1,
  91 #include "categories.def"
  92 #undef  DEFINE_CATEGORY
  93     [LC_ALL] = sizeof ("LC_ALL") - 1
  94   };
  95
  96
  97 #ifdef NL_CURRENT_INDIRECT
  98 # define WEAK_POSTLOAD(postload) weak_extern (postload)
  99 #else
 100 # define WEAK_POSTLOAD(postload) /* Need strong refs in static linking.  */
 101 #endif
 102
 103 /* Declare the postload functions used below.  */
 104 #undef  NO_POSTLOAD
 105 #define NO_POSTLOAD _nl_postload_ctype /* Harmless thing known to exist.  */
 106 #define DEFINE_CATEGORY(category, category_name, items, postload) \
 107 extern void postload (void); WEAK_POSTLOAD (postload)
 108 #include "categories.def"
 109 #undef  DEFINE_CATEGORY
 110 #undef  NO_POSTLOAD
 111
 112 /* Define an array indexed by category of postload functions to call after
 113    loading and installing that category's data.  */
 114 static void (*const _nl_category_postload[]) (void) =
 115   {
 116 #define DEFINE_CATEGORY(category, category_name, items, postload) \
 117     [category] = postload,
 118 #include "categories.def"
 119 #undef  DEFINE_CATEGORY
 120   };
 121
 122
 123 /* Lock for protecting global data.  */
 124 __libc_rwlock_define_initialized (, __libc_setlocale_lock attribute_hidden)
 125
 126 /* Defined in loadmsgcat.c.  */
 127 extern int _nl_msg_cat_cntr;
 128
 129
 130 /* Use this when we come along an error.  */
 131 #define ERROR_RETURN                                                          \
 132   do {                                                                        \
 133     __set_errno (EINVAL);                                                     \
 134     return NULL;                                                              \
 135   } while (0)
 136
 137
 138 /* Construct a new composite name.  */
 139 static char *
 140 new_composite_name (int category, const char *newnames[__LC_LAST])
 141 {
 142   size_t last_len = 0;
 143   size_t cumlen = 0;
 144   int i;
 145   char *new, *p;
 146   int same = 1;
 147
 148   for (i = 0; i < __LC_LAST; ++i)
 149     if (i != LC_ALL)
 150       {
 151         const char *name = (category == LC_ALL ? newnames[i] :
 152                             category == i ? newnames[0] :
 153                             _nl_global_locale.__names[i]);
 154         last_len = strlen (name);
 155         cumlen += _nl_category_name_sizes[i] + 1 + last_len + 1;
 156         if (same && name != newnames[0] && strcmp (name, newnames[0]) != 0)
 157           same = 0;
 158       }
 159
 160   if (same)
 161     {
 162       /* All the categories use the same name.  */
 163       if (strcmp (newnames[0], _nl_C_name) == 0
 164           || strcmp (newnames[0], _nl_POSIX_name) == 0)
 165         return (char *) _nl_C_name;
 166
 167       new = malloc (last_len + 1);
 168
 169       return new == NULL ? NULL : memcpy (new, newnames[0], last_len + 1);
 170     }
 171
 172   new = malloc (cumlen);
 173   if (new == NULL)
 174     return NULL;
 175   p = new;
 176   for (i = 0; i < __LC_LAST; ++i)
 177     if (i != LC_ALL)
 178       {
 179         /* Add "CATEGORY=NAME;" to the string.  */
 180         const char *name = (category == LC_ALL ? newnames[i] :
 181                             category == i ? newnames[0] :
 182                             _nl_global_locale.__names[i]);
 183         p = __stpcpy (p, _nl_category_names.str + _nl_category_name_idxs[i]);
 184         *p++ = '=';
 185         p = __stpcpy (p, name);
 186         *p++ = ';';
 187       }
 188   p[-1] = '\0';         /* Clobber the last ';'.  */
 189   return new;
 190 }
 191
 192
 193 /* Put NAME in _nl_global_locale.__names.  */
 194 static void
 195 setname (int category, const char *name)
 196 {
 197   if (_nl_global_locale.__names[category] == name)
 198     return;
 199
 200   if (_nl_global_locale.__names[category] != _nl_C_name)
 201     free ((char *) _nl_global_locale.__names[category]);
 202
 203   _nl_global_locale.__names[category] = name;
 204 }
 205
 206 /* Put DATA in *_nl_current[CATEGORY].  */
 207 static void
 208 setdata (int category, struct __locale_data *data)
 209 {
 210   if (CATEGORY_USED (category))
 211     {
 212       _nl_global_locale.__locales[category] = data;
 213       if (_nl_category_postload[category])
 214         (*_nl_category_postload[category]) ();
 215     }
 216 }
 217
 218 char *
 219 setlocale (int category, const char *locale)
 220 {
 221   char *locale_path;
 222   size_t locale_path_len;
 223   const char *locpath_var;
 224   char *composite;
 225
 226   /* Sanity check for CATEGORY argument.  */
 227   if (__builtin_expect (category, 0) < 0
 228       || __builtin_expect (category, 0) >= __LC_LAST)
 229     ERROR_RETURN;
 230
 231   /* Does user want name of current locale?  */
 232   if (locale == NULL)
 233     return (char *) _nl_global_locale.__names[category];
 234
 235   /* Protect global data.  */
 236   __libc_rwlock_wrlock (__libc_setlocale_lock);
 237
 238   if (strcmp (locale, _nl_global_locale.__names[category]) == 0)
 239     {
 240       /* Changing to the same thing.  */
 241       __libc_rwlock_unlock (__libc_setlocale_lock);
 242
 243       return (char *) _nl_global_locale.__names[category];
 244     }
 245
 246   /* We perhaps really have to load some data.  So we determine the
 247      path in which to look for the data now.  The environment variable
 248      `LOCPATH' must only be used when the binary has no SUID or SGID
 249      bit set.  If using the default path, we tell _nl_find_locale
 250      by passing null and it can check the canonical locale archive.  */
 251   locale_path = NULL;
 252   locale_path_len = 0;
 253
 254   locpath_var = getenv ("LOCPATH");
 255   if (locpath_var != NULL && locpath_var[0] != '\0')
 256     {
 257       if (__argz_create_sep (locpath_var, ':',
 258                              &locale_path, &locale_path_len) != 0
 259           || __argz_add_sep (&locale_path, &locale_path_len,
 260                              _nl_default_locale_path, ':') != 0)
 261         {
 262           __libc_rwlock_unlock (__libc_setlocale_lock);
 263           return NULL;
 264         }
 265     }
 266
 267   if (category == LC_ALL)
 268     {
 269       /* The user wants to set all categories.  The desired locales
 270          for the individual categories can be selected by using a
 271          composite locale name.  This is a semi-colon separated list
 272          of entries of the form `CATEGORY=VALUE'.  */
 273       const char *newnames[__LC_LAST];
 274       struct __locale_data *newdata[__LC_LAST];
 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 (__builtin_expect (strchr (locale, ';') != NULL, 0))
 282         {
 283           /* This is a composite name.  Make a copy and split it up.  */
 284           char *np = strdupa (locale);
 285           char *cp;
 286           int cnt;
 287
 288           while ((cp = strchr (np, '=')) != NULL)
 289             {
 290               for (cnt = 0; cnt < __LC_LAST; ++cnt)
 291                 if (cnt != LC_ALL
 292                     && (size_t) (cp - np) == _nl_category_name_sizes[cnt]
 293                     && (memcmp (np, (_nl_category_names.str
 294                                      + _nl_category_name_idxs[cnt]), cp - np)
 295                         == 0))
 296                   break;
 297
 298               if (cnt == __LC_LAST)
 299                 {
 300                 error_return:
 301                   __libc_rwlock_unlock (__libc_setlocale_lock);
 302
 303                   /* Bogus category name.  */
 304                   ERROR_RETURN;
 305                 }
 306
 307               /* Found the category this clause sets.  */
 308               newnames[cnt] = ++cp;
 309               cp = strchr (cp, ';');
 310               if (cp != NULL)
 311                 {
 312                   /* Examine the next clause.  */
 313                   *cp = '\0';
 314                   np = cp + 1;
 315                 }
 316               else
 317                 /* This was the last clause.  We are done.  */
 318                 break;
 319             }
 320
 321           for (cnt = 0; cnt < __LC_LAST; ++cnt)
 322             if (cnt != LC_ALL && newnames[cnt] == locale)
 323               /* The composite name did not specify all categories.  */
 324               goto error_return;
 325         }
 326
 327       /* Load the new data for each category.  */
 328       while (category-- > 0)
 329         if (category != LC_ALL)
 330           {
 331             newdata[category] = _nl_find_locale (locale_path, locale_path_len,
 332                                                  category,
 333                                                  &newnames[category]);
 334
 335             if (newdata[category] == NULL)
 336               {
 337 #ifdef NL_CURRENT_INDIRECT
 338                 if (newnames[category] == _nl_C_name)
 339                   /* Null because it's the weak value of _nl_C_LC_FOO.  */
 340                   continue;
 341 #endif
 342                 break;
 343               }
 344
 345             /* We must not simply free a global locale since we have
 346                no control over the usage.  So we mark it as
 347                un-deletable.  And yes, the 'if' is needed, the data
 348                might be in read-only memory.  */
 349             if (newdata[category]->usage_count != UNDELETABLE)
 350               newdata[category]->usage_count = UNDELETABLE;
 351
 352             /* Make a copy of locale name.  */
 353             if (newnames[category] != _nl_C_name)
 354               {
 355                 if (strcmp (newnames[category],
 356                             _nl_global_locale.__names[category]) == 0)
 357                   newnames[category] = _nl_global_locale.__names[category];
 358                 else
 359                   {
 360                     newnames[category] = __strdup (newnames[category]);
 361                     if (newnames[category] == NULL)
 362                       break;
 363                   }
 364               }
 365           }
 366
 367       /* Create new composite name.  */
 368       composite = (category >= 0
 369                    ? NULL : new_composite_name (LC_ALL, newnames));
 370       if (composite != NULL)
 371         {
 372           /* Now we have loaded all the new data.  Put it in place.  */
 373           for (category = 0; category < __LC_LAST; ++category)
 374             if (category != LC_ALL)
 375               {
 376                 setdata (category, newdata[category]);
 377                 setname (category, newnames[category]);
 378               }
 379           setname (LC_ALL, composite);
 380
 381           /* We successfully loaded a new locale.  Let the message catalog
 382              functions know about this.  */
 383           ++_nl_msg_cat_cntr;
 384         }
 385       else
 386         for (++category; category < __LC_LAST; ++category)
 387           if (category != LC_ALL && newnames[category] != _nl_C_name
 388               && newnames[category] != _nl_global_locale.__names[category])
 389             free ((char *) newnames[category]);
 390
 391       /* Critical section left.  */
 392       __libc_rwlock_unlock (__libc_setlocale_lock);
 393
 394       /* Free the resources (the locale path variable).  */
 395       free (locale_path);
 396
 397       return composite;
 398     }
 399   else
 400     {
 401       struct __locale_data *newdata = NULL;
 402       const char *newname[1] = { locale };
 403
 404       if (CATEGORY_USED (category))
 405         {
 406           /* Only actually load the data if anything will use it.  */
 407           newdata = _nl_find_locale (locale_path, locale_path_len, category,
 408                                      &newname[0]);
 409           if (newdata == NULL)
 410             goto abort_single;
 411
 412           /* We must not simply free a global locale since we have no
 413              control over the usage.  So we mark it as un-deletable.
 414
 415              Note: do not remove the `if', it's necessary to copy with
 416              the builtin locale data.  */
 417           if (newdata->usage_count != UNDELETABLE)
 418             newdata->usage_count = UNDELETABLE;
 419         }
 420
 421       /* Make a copy of locale name.  */
 422       if (newname[0] != _nl_C_name)
 423         {
 424           newname[0] = __strdup (newname[0]);
 425           if (newname[0] == NULL)
 426             goto abort_single;
 427         }
 428
 429       /* Create new composite name.  */
 430       composite = new_composite_name (category, newname);
 431       if (composite == NULL)
 432         {
 433           if (newname[0] != _nl_C_name)
 434             free ((char *) newname[0]);
 435
 436           /* Say that we don't have any data loaded.  */
 437         abort_single:
 438           newname[0] = NULL;
 439         }
 440       else
 441         {
 442           if (CATEGORY_USED (category))
 443             setdata (category, newdata);
 444
 445           setname (category, newname[0]);
 446           setname (LC_ALL, composite);
 447
 448           /* We successfully loaded a new locale.  Let the message catalog
 449              functions know about this.  */
 450           ++_nl_msg_cat_cntr;
 451         }
 452
 453       /* Critical section left.  */
 454       __libc_rwlock_unlock (__libc_setlocale_lock);
 455
 456       /* Free the resources (the locale path variable.  */
 457       free (locale_path);
 458
 459       return (char *) newname[0];
 460     }
 461 }
 462 libc_hidden_def (setlocale)
 463
 464 static void __libc_freeres_fn_section
 465 free_category (int category,
 466                struct __locale_data *here, struct __locale_data *c_data)
 467 {
 468   struct loaded_l10nfile *runp = _nl_locale_file_list[category];
 469
 470   /* If this category is already "C" don't do anything.  */
 471   if (here != c_data)
 472     {
 473       /* We have to be prepared that sometime later we still
 474          might need the locale information.  */
 475       setdata (category, c_data);
 476       setname (category, _nl_C_name);
 477     }
 478
 479   while (runp != NULL)
 480     {
 481       struct loaded_l10nfile *curr = runp;
 482       struct __locale_data *data = (struct __locale_data *) runp->data;
 483
 484       if (data != NULL && data != c_data)
 485         _nl_unload_locale (data);
 486       runp = runp->next;
 487       free ((char *) curr->filename);
 488       free (curr);
 489     }
 490 }
 491
 492 /* This is called from iconv/gconv_db.c's free_mem, as locales must
 493    be freed before freeing gconv steps arrays.  */
 494 void __libc_freeres_fn_section
 495 _nl_locale_subfreeres (void)
 496 {
 497 #ifdef NL_CURRENT_INDIRECT
 498   /* We don't use the loop because we want to have individual weak
 499      symbol references here.  */
 500 # define DEFINE_CATEGORY(category, category_name, items, a)                   \
 501   if (CATEGORY_USED (category))                                               \
 502     {                                                                         \
 503       extern struct __locale_data _nl_C_##category;                           \
 504       weak_extern (_nl_C_##category)                                          \
 505       free_category (category, *_nl_current_##category, &_nl_C_##category);   \
 506     }
 507 # include "categories.def"
 508 # undef DEFINE_CATEGORY
 509 #else
 510   int category;
 511
 512   for (category = 0; category < __LC_LAST; ++category)
 513     if (category != LC_ALL)
 514       free_category (category, _NL_CURRENT_DATA (category),
 515                      _nl_C_locobj.__locales[category]);
 516 #endif
 517
 518   setname (LC_ALL, _nl_C_name);
 519
 520   /* This frees the data structures associated with the locale archive.
 521      The locales from the archive are not in the file list, so we have
 522      not called _nl_unload_locale on them above.  */
 523   _nl_archive_subfreeres ();
 524 }