locale/setlocale.c

   1 /* Copyright (C) 1991, 92, 95-99, 2000 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 Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    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    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 #include <alloca.h>
  20 #include <argz.h>
  21 #include <errno.h>
  22 #include <bits/libc-lock.h>
  23 #include <locale.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <unistd.h>
  27
  28 #include "localeinfo.h"
  29
  30 /* For each category declare two external variables (with weak references):
  31      extern const struct locale_data *_nl_current_CATEGORY;
  32    This points to the current locale's in-core data for CATEGORY.
  33      extern const struct locale_data _nl_C_CATEGORY;
  34    This contains the built-in "C"/"POSIX" locale's data for CATEGORY.
  35    Both are weak references; if &_nl_current_CATEGORY is zero,
  36    then nothing is using the locale data.  */
  37 #define DEFINE_CATEGORY(category, category_name, items, a) \
  38 extern struct locale_data *_nl_current_##category;                            \
  39 extern struct locale_data _nl_C_##category;
  40 #include "categories.def"
  41 #undef  DEFINE_CATEGORY
  42
  43 /* Array indexed by category of pointers to _nl_current_CATEGORY slots.
  44    Elements are zero for categories whose data is never used.  */
  45 struct locale_data * *const _nl_current[] =
  46   {
  47 #define DEFINE_CATEGORY(category, category_name, items, a) \
  48     [category] = &_nl_current_##category,
  49 #include "categories.def"
  50 #undef  DEFINE_CATEGORY
  51     /* We need this additional element to simplify the code.  It must
  52        simply be != NULL.  */
  53     [LC_ALL] = (struct locale_data **) ~0ul
  54   };
  55
  56 /* Array indexed by category of pointers to _nl_C_CATEGORY slots.
  57    Elements are zero for categories whose data is never used.  */
  58 struct locale_data *const _nl_C[] =
  59   {
  60 #define DEFINE_CATEGORY(category, category_name, items, a) \
  61     [category] = &_nl_C_##category,
  62 #include "categories.def"
  63 #undef  DEFINE_CATEGORY
  64   };
  65
  66
  67 /* Define an array of category names (also the environment variable names),
  68    indexed by integral category.  */
  69 const char *const _nl_category_names[] =
  70   {
  71 #define DEFINE_CATEGORY(category, category_name, items, a) \
  72     [category] = category_name,
  73 #include "categories.def"
  74 #undef  DEFINE_CATEGORY
  75     [LC_ALL] = "LC_ALL"
  76   };
  77 /* An array of their lengths, for convenience.  */
  78 const size_t _nl_category_name_sizes[] =
  79   {
  80 #define DEFINE_CATEGORY(category, category_name, items, a) \
  81     [category] = sizeof (category_name) - 1,
  82 #include "categories.def"
  83 #undef  DEFINE_CATEGORY
  84     [LC_ALL] = sizeof ("LC_ALL") - 1
  85   };
  86
  87
  88 /* Declare the postload functions used below.  */
  89 #undef  NO_POSTLOAD
  90 #define NO_POSTLOAD _nl_postload_ctype /* Harmless thing known to exist.  */
  91 #define DEFINE_CATEGORY(category, category_name, items, postload) \
  92 extern void postload (void);
  93 #include "categories.def"
  94 #undef  DEFINE_CATEGORY
  95 #undef  NO_POSTLOAD
  96
  97 /* Define an array indexed by category of postload functions to call after
  98    loading and installing that category's data.  */
  99 static void (*const _nl_category_postload[]) (void) =
 100   {
 101 #define DEFINE_CATEGORY(category, category_name, items, postload) \
 102     [category] = postload,
 103 #include "categories.def"
 104 #undef  DEFINE_CATEGORY
 105   };
 106
 107
 108 /* Name of current locale for each individual category.
 109    Each is malloc'd unless it is nl_C_name.  */
 110 static const char *_nl_current_names[] =
 111   {
 112 #define DEFINE_CATEGORY(category, category_name, items, a) \
 113     [category] = _nl_C_name,
 114 #include "categories.def"
 115 #undef  DEFINE_CATEGORY
 116     [LC_ALL] = _nl_C_name               /* For LC_ALL.  */
 117   };
 118
 119
 120 /* Lock for protecting global data.  */
 121 __libc_lock_define_initialized (, __libc_setlocale_lock)
 122
 123 /* Defined in loadmsgcat.c.  */
 124 extern int _nl_msg_cat_cntr;
 125
 126
 127 /* Use this when we come along an error.  */
 128 #define ERROR_RETURN                                                          \
 129   do {                                                                        \
 130     __set_errno (EINVAL);                                                     \
 131     return NULL;                                                              \
 132   } while (0)
 133
 134
 135 /* Construct a new composite name.  */
 136 static inline char *
 137 new_composite_name (int category, const char *newnames[__LC_LAST])
 138 {
 139   size_t last_len = 0;
 140   size_t cumlen = 0;
 141   int i;
 142   char *new, *p;
 143   int same = 1;
 144
 145   for (i = 0; i < __LC_LAST; ++i)
 146     if (i != LC_ALL)
 147       {
 148         const char *name = (category == LC_ALL ? newnames[i] :
 149                             category == i ? newnames[0] :
 150                             _nl_current_names[i]);
 151         last_len = strlen (name);
 152         cumlen += _nl_category_name_sizes[i] + 1 + last_len + 1;
 153         if (i > 0 && same && strcmp (name, newnames[0]) != 0)
 154           same = 0;
 155       }
 156
 157   if (same)
 158     {
 159       /* All the categories use the same name.  */
 160       if (strcmp (newnames[0], _nl_C_name) == 0
 161           || strcmp (newnames[0], _nl_POSIX_name) == 0)
 162         return (char *) _nl_C_name;
 163
 164       new = malloc (last_len + 1);
 165
 166       return new == NULL ? NULL : memcpy (new, newnames[0], last_len + 1);
 167     }
 168
 169   new = malloc (cumlen);
 170   if (new == NULL)
 171     return NULL;
 172   p = new;
 173   for (i = 0; i < __LC_LAST; ++i)
 174     if (i != LC_ALL)
 175       {
 176         /* Add "CATEGORY=NAME;" to the string.  */
 177         const char *name = (category == LC_ALL ? newnames[i] :
 178                             category == i ? newnames[0] :
 179                             _nl_current_names[i]);
 180         p = __stpcpy (p, _nl_category_names[i]);
 181         *p++ = '=';
 182         p = __stpcpy (p, name);
 183         *p++ = ';';
 184       }
 185   p[-1] = '\0';         /* Clobber the last ';'.  */
 186   return new;
 187 }
 188
 189
 190 /* Put NAME in _nl_current_names.  */
 191 static inline void
 192 setname (int category, const char *name)
 193 {
 194   if (_nl_current_names[category] == name)
 195     return;
 196
 197   if (_nl_current_names[category] != _nl_C_name)
 198     free ((char *) _nl_current_names[category]);
 199
 200   _nl_current_names[category] = name;
 201 }
 202
 203
 204 /* Put DATA in *_nl_current[CATEGORY].  */
 205 static inline void
 206 setdata (int category, struct locale_data *data)
 207 {
 208   if (_nl_current[category] != NULL)
 209     {
 210       *_nl_current[category] = data;
 211       if (_nl_category_postload[category])
 212         (*_nl_category_postload[category]) ();
 213     }
 214 }
 215
 216
 217 char *
 218 setlocale (int category, const char *locale)
 219 {
 220   char *locale_path;
 221   size_t locale_path_len;
 222   const char *locpath_var;
 223   char *composite;
 224
 225   /* Sanity check for CATEGORY argument.  */
 226   if (__builtin_expect (category, 0) < 0
 227       || __builtin_expect (category, 0) >= __LC_LAST)
 228     ERROR_RETURN;
 229
 230   /* Does user want name of current locale?  */
 231   if (locale == NULL)
 232     return (char *) _nl_current_names[category];
 233
 234   if (strcmp (locale, _nl_current_names[category]) == 0)
 235     /* Changing to the same thing.  */
 236     return (char *) _nl_current_names[category];
 237
 238   /* We perhaps really have to load some data.  So we determine the
 239      path in which to look for the data now.  The environment variable
 240      `LOCPATH' must only be used when the binary has no SUID or SGID
 241      bit set.  */
 242   locale_path = NULL;
 243   locale_path_len = 0;
 244
 245   locpath_var = getenv ("LOCPATH");
 246   if (locpath_var != NULL && locpath_var[0] != '\0')
 247     if (__argz_create_sep (locpath_var, ':',
 248                            &locale_path, &locale_path_len) != 0)
 249       return NULL;
 250
 251   if (__argz_add_sep (&locale_path, &locale_path_len, LOCALEDIR, ':') != 0)
 252     return NULL;
 253
 254   if (category == LC_ALL)
 255     {
 256       /* The user wants to set all categories.  The desired locales
 257          for the individual categories can be selected by using a
 258          composite locale name.  This is a semi-colon separated list
 259          of entries of the form `CATEGORY=VALUE'.  */
 260       const char *newnames[__LC_LAST];
 261       struct locale_data *newdata[__LC_LAST];
 262
 263       /* Set all name pointers to the argument name.  */
 264       for (category = 0; category < __LC_LAST; ++category)
 265         if (category != LC_ALL)
 266           newnames[category] = (char *) locale;
 267
 268       if (__builtin_expect (strchr (locale, ';') != NULL, 0))
 269         {
 270           /* This is a composite name.  Make a copy and split it up.  */
 271           char *np = strdupa (locale);
 272           char *cp;
 273           int cnt;
 274
 275           while ((cp = strchr (np, '=')) != NULL)
 276             {
 277               for (cnt = 0; cnt < __LC_LAST; ++cnt)
 278                 if (cnt != LC_ALL
 279                     && (size_t) (cp - np) == _nl_category_name_sizes[cnt]
 280                     && memcmp (np, _nl_category_names[cnt], cp - np) == 0)
 281                   break;
 282
 283               if (cnt == __LC_LAST)
 284                 /* Bogus category name.  */
 285                 ERROR_RETURN;
 286
 287               /* Found the category this clause sets.  */
 288               newnames[cnt] = ++cp;
 289               cp = strchr (cp, ';');
 290               if (cp != NULL)
 291                 {
 292                   /* Examine the next clause.  */
 293                   *cp = '\0';
 294                   np = cp + 1;
 295                 }
 296               else
 297                 /* This was the last clause.  We are done.  */
 298                 break;
 299             }
 300
 301           for (cnt = 0; cnt < __LC_LAST; ++cnt)
 302             if (cnt != LC_ALL && newnames[cnt] == locale)
 303               /* The composite name did not specify all categories.  */
 304               ERROR_RETURN;
 305         }
 306
 307       /* Protect global data.  */
 308       __libc_lock_lock (__libc_setlocale_lock);
 309
 310       /* Load the new data for each category.  */
 311       while (category-- > 0)
 312         if (category != LC_ALL)
 313           {
 314             newdata[category] = _nl_find_locale (locale_path, locale_path_len,
 315                                                  category,
 316                                                  &newnames[category]);
 317
 318             if (newdata[category] == NULL)
 319               break;
 320
 321             /* We must not simply free a global locale since we have no
 322                control over the usage.  So we mark it as un-deletable.  */
 323             if (newdata[category]->usage_count != UNDELETABLE)
 324               newdata[category]->usage_count = UNDELETABLE;
 325
 326             /* Make a copy of locale name.  */
 327             if (newnames[category] != _nl_C_name)
 328               {
 329                 newnames[category] = strdup (newnames[category]);
 330                 if (newnames[category] == NULL)
 331                   break;
 332               }
 333           }
 334
 335       /* Create new composite name.  */
 336       composite = (category >= 0
 337                    ? NULL : new_composite_name (LC_ALL, newnames));
 338       if (composite != NULL)
 339         {
 340           /* Now we have loaded all the new data.  Put it in place.  */
 341           for (category = 0; category < __LC_LAST; ++category)
 342             if (category != LC_ALL)
 343               {
 344                 setdata (category, newdata[category]);
 345                 setname (category, newnames[category]);
 346               }
 347           setname (LC_ALL, composite);
 348
 349           /* We successfully loaded a new locale.  Let the message catalog
 350              functions know about this.  */
 351           ++_nl_msg_cat_cntr;
 352         }
 353       else
 354         for (++category; category < __LC_LAST; ++category)
 355           if (category != LC_ALL && newnames[category] != _nl_C_name)
 356             free ((char *) newnames[category]);
 357
 358       /* Critical section left.  */
 359       __libc_lock_unlock (__libc_setlocale_lock);
 360
 361       /* Free the resources (the locale path variable.  */
 362       free (locale_path);
 363
 364       return composite;
 365     }
 366   else
 367     {
 368       struct locale_data *newdata = NULL;
 369       const char *newname[1] = { locale };
 370
 371       /* Protect global data.  */
 372       __libc_lock_lock (__libc_setlocale_lock);
 373
 374       if (_nl_current[category] != NULL)
 375         {
 376           /* Only actually load the data if anything will use it.  */
 377           newdata = _nl_find_locale (locale_path, locale_path_len, category,
 378                                      &newname[0]);
 379           if (newdata == NULL)
 380             goto abort_single;
 381
 382           /* We must not simply free a global locale since we have no
 383              control over the usage.  So we mark it as un-deletable.
 384
 385              Note: do not remove the `if', it's necessary to copy with
 386              the builtin locale data.  */
 387           if (newdata->usage_count != UNDELETABLE)
 388             newdata->usage_count = UNDELETABLE;
 389         }
 390
 391       /* Make a copy of locale name.  */
 392       if (newname[0] != _nl_C_name)
 393         {
 394           newname[0] = strdup (newname[0]);
 395           if (newname[0] == NULL)
 396             goto abort_single;
 397         }
 398
 399       /* Create new composite name.  */
 400       composite = new_composite_name (category, newname);
 401       if (composite == NULL)
 402         {
 403           if (newname[0] != _nl_C_name)
 404             free ((char *) newname[0]);
 405
 406           /* Say that we don't have any data loaded.  */
 407         abort_single:
 408           newname[0] = NULL;
 409         }
 410       else
 411         {
 412           if (_nl_current[category] != NULL)
 413             setdata (category, newdata);
 414
 415           setname (category, newname[0]);
 416           setname (LC_ALL, composite);
 417
 418           /* We successfully loaded a new locale.  Let the message catalog
 419              functions know about this.  */
 420           ++_nl_msg_cat_cntr;
 421         }
 422
 423       /* Critical section left.  */
 424       __libc_lock_unlock (__libc_setlocale_lock);
 425
 426       /* Free the resources (the locale path variable.  */
 427       free (locale_path);
 428
 429       return (char *) newname[0];
 430     }
 431 }
 432
 433
 434 static void __attribute__ ((unused))
 435 free_mem (void)
 436 {
 437   int category;
 438
 439   for (category = 0; category < __LC_LAST; ++category)
 440     if (category != LC_ALL)
 441       {
 442         struct locale_data *here = *_nl_current[category];
 443
 444         /* If this category is already "C" don't do anything.  */
 445         if (here == _nl_C[category])
 446           continue;
 447
 448         /* We have to be prepared that sometime later me still might
 449            need the locale information.  */
 450         setdata (category, _nl_C[category]);
 451         setname (category, _nl_C_name);
 452
 453         _nl_unload_locale (here);
 454       }
 455
 456   setname (LC_ALL, _nl_C_name);
 457 }
 458 text_set_element (__libc_subfreeres, free_mem);