locale/setlocale.c

   1 /* Copyright (C) 1991-2017 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 <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       /* Copy of the locale argument, for in-place splitting.  */
 276       char *locale_copy = NULL;
 277
 278       /* Set all name pointers to the argument name.  */
 279       for (category = 0; category < __LC_LAST; ++category)
 280         if (category != LC_ALL)
 281           newnames[category] = (char *) locale;
 282
 283       if (__glibc_unlikely (strchr (locale, ';') != NULL))
 284         {
 285           /* This is a composite name.  Make a copy and split it up.  */
 286           locale_copy = __strdup (locale);
 287           if (__glibc_unlikely (locale_copy == NULL))
 288             {
 289               __libc_rwlock_unlock (__libc_setlocale_lock);
 290               return NULL;
 291             }
 292           char *np = locale_copy;
 293           char *cp;
 294           int cnt;
 295
 296           while ((cp = strchr (np, '=')) != NULL)
 297             {
 298               for (cnt = 0; cnt < __LC_LAST; ++cnt)
 299                 if (cnt != LC_ALL
 300                     && (size_t) (cp - np) == _nl_category_name_sizes[cnt]
 301                     && (memcmp (np, (_nl_category_names.str
 302                                      + _nl_category_name_idxs[cnt]), cp - np)
 303                         == 0))
 304                   break;
 305
 306               if (cnt == __LC_LAST)
 307                 {
 308                 error_return:
 309                   __libc_rwlock_unlock (__libc_setlocale_lock);
 310                   free (locale_copy);
 311
 312                   /* Bogus category name.  */
 313                   ERROR_RETURN;
 314                 }
 315
 316               /* Found the category this clause sets.  */
 317               newnames[cnt] = ++cp;
 318               cp = strchr (cp, ';');
 319               if (cp != NULL)
 320                 {
 321                   /* Examine the next clause.  */
 322                   *cp = '\0';
 323                   np = cp + 1;
 324                 }
 325               else
 326                 /* This was the last clause.  We are done.  */
 327                 break;
 328             }
 329
 330           for (cnt = 0; cnt < __LC_LAST; ++cnt)
 331             if (cnt != LC_ALL && newnames[cnt] == locale)
 332               /* The composite name did not specify all categories.  */
 333               goto error_return;
 334         }
 335
 336       /* Load the new data for each category.  */
 337       while (category-- > 0)
 338         if (category != LC_ALL)
 339           {
 340             newdata[category] = _nl_find_locale (locale_path, locale_path_len,
 341                                                  category,
 342                                                  &newnames[category]);
 343
 344             if (newdata[category] == NULL)
 345               {
 346 #ifdef NL_CURRENT_INDIRECT
 347                 if (newnames[category] == _nl_C_name)
 348                   /* Null because it's the weak value of _nl_C_LC_FOO.  */
 349                   continue;
 350 #endif
 351                 break;
 352               }
 353
 354             /* We must not simply free a global locale since we have
 355                no control over the usage.  So we mark it as
 356                un-deletable.  And yes, the 'if' is needed, the data
 357                might be in read-only memory.  */
 358             if (newdata[category]->usage_count != UNDELETABLE)
 359               newdata[category]->usage_count = UNDELETABLE;
 360
 361             /* Make a copy of locale name.  */
 362             if (newnames[category] != _nl_C_name)
 363               {
 364                 if (strcmp (newnames[category],
 365                             _nl_global_locale.__names[category]) == 0)
 366                   newnames[category] = _nl_global_locale.__names[category];
 367                 else
 368                   {
 369                     newnames[category] = __strdup (newnames[category]);
 370                     if (newnames[category] == NULL)
 371                       break;
 372                   }
 373               }
 374           }
 375
 376       /* Create new composite name.  */
 377       composite = (category >= 0
 378                    ? NULL : new_composite_name (LC_ALL, newnames));
 379       if (composite != NULL)
 380         {
 381           /* Now we have loaded all the new data.  Put it in place.  */
 382           for (category = 0; category < __LC_LAST; ++category)
 383             if (category != LC_ALL)
 384               {
 385                 setdata (category, newdata[category]);
 386                 setname (category, newnames[category]);
 387               }
 388           setname (LC_ALL, composite);
 389
 390           /* We successfully loaded a new locale.  Let the message catalog
 391              functions know about this.  */
 392           ++_nl_msg_cat_cntr;
 393         }
 394       else
 395         for (++category; category < __LC_LAST; ++category)
 396           if (category != LC_ALL && newnames[category] != _nl_C_name
 397               && newnames[category] != _nl_global_locale.__names[category])
 398             free ((char *) newnames[category]);
 399
 400       /* Critical section left.  */
 401       __libc_rwlock_unlock (__libc_setlocale_lock);
 402
 403       /* Free the resources.  */
 404       free (locale_path);
 405       free (locale_copy);
 406
 407       return composite;
 408     }
 409   else
 410     {
 411       struct __locale_data *newdata = NULL;
 412       const char *newname[1] = { locale };
 413
 414       if (CATEGORY_USED (category))
 415         {
 416           /* Only actually load the data if anything will use it.  */
 417           newdata = _nl_find_locale (locale_path, locale_path_len, category,
 418                                      &newname[0]);
 419           if (newdata == NULL)
 420             goto abort_single;
 421
 422           /* We must not simply free a global locale since we have no
 423              control over the usage.  So we mark it as un-deletable.
 424
 425              Note: do not remove the `if', it's necessary to cope with
 426              the builtin locale data.  */
 427           if (newdata->usage_count != UNDELETABLE)
 428             newdata->usage_count = UNDELETABLE;
 429         }
 430
 431       /* Make a copy of locale name.  */
 432       if (newname[0] != _nl_C_name)
 433         {
 434           newname[0] = __strdup (newname[0]);
 435           if (newname[0] == NULL)
 436             goto abort_single;
 437         }
 438
 439       /* Create new composite name.  */
 440       composite = new_composite_name (category, newname);
 441       if (composite == NULL)
 442         {
 443           if (newname[0] != _nl_C_name)
 444             free ((char *) newname[0]);
 445
 446           /* Say that we don't have any data loaded.  */
 447         abort_single:
 448           newname[0] = NULL;
 449         }
 450       else
 451         {
 452           if (CATEGORY_USED (category))
 453             setdata (category, newdata);
 454
 455           setname (category, newname[0]);
 456           setname (LC_ALL, composite);
 457
 458           /* We successfully loaded a new locale.  Let the message catalog
 459              functions know about this.  */
 460           ++_nl_msg_cat_cntr;
 461         }
 462
 463       /* Critical section left.  */
 464       __libc_rwlock_unlock (__libc_setlocale_lock);
 465
 466       /* Free the resources (the locale path variable.  */
 467       free (locale_path);
 468
 469       return (char *) newname[0];
 470     }
 471 }
 472 libc_hidden_def (setlocale)
 473
 474 static void __libc_freeres_fn_section
 475 free_category (int category,
 476                struct __locale_data *here, struct __locale_data *c_data)
 477 {
 478   struct loaded_l10nfile *runp = _nl_locale_file_list[category];
 479
 480   /* If this category is already "C" don't do anything.  */
 481   if (here != c_data)
 482     {
 483       /* We have to be prepared that sometime later we still
 484          might need the locale information.  */
 485       setdata (category, c_data);
 486       setname (category, _nl_C_name);
 487     }
 488
 489   while (runp != NULL)
 490     {
 491       struct loaded_l10nfile *curr = runp;
 492       struct __locale_data *data = (struct __locale_data *) runp->data;
 493
 494       if (data != NULL && data != c_data)
 495         _nl_unload_locale (data);
 496       runp = runp->next;
 497       free ((char *) curr->filename);
 498       free (curr);
 499     }
 500 }
 501
 502 /* This is called from iconv/gconv_db.c's free_mem, as locales must
 503    be freed before freeing gconv steps arrays.  */
 504 void __libc_freeres_fn_section
 505 _nl_locale_subfreeres (void)
 506 {
 507 #ifdef NL_CURRENT_INDIRECT
 508   /* We don't use the loop because we want to have individual weak
 509      symbol references here.  */
 510 # define DEFINE_CATEGORY(category, category_name, items, a)                   \
 511   if (CATEGORY_USED (category))                                               \
 512     {                                                                         \
 513       extern struct __locale_data _nl_C_##category;                           \
 514       weak_extern (_nl_C_##category)                                          \
 515       free_category (category, *_nl_current_##category, &_nl_C_##category);   \
 516     }
 517 # include "categories.def"
 518 # undef DEFINE_CATEGORY
 519 #else
 520   int category;
 521
 522   for (category = 0; category < __LC_LAST; ++category)
 523     if (category != LC_ALL)
 524       free_category (category, _NL_CURRENT_DATA (category),
 525                      _nl_C_locobj.__locales[category]);
 526 #endif
 527
 528   setname (LC_ALL, _nl_C_name);
 529
 530   /* This frees the data structures associated with the locale archive.
 531      The locales from the archive are not in the file list, so we have
 532      not called _nl_unload_locale on them above.  */
 533   _nl_archive_subfreeres ();
 534 }