locale/newlocale.c

   1 /* Return a reference to locale information record.
   2    Copyright (C) 1996-2016 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #include <argz.h>
  21 #include <libc-lock.h>
  22 #include <errno.h>
  23 #include <locale.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26
  27 #include "localeinfo.h"
  28
  29
  30 /* Lock for protecting global data.  */
  31 __libc_rwlock_define (extern , __libc_setlocale_lock attribute_hidden)
  32
  33
  34 /* Use this when we come along an error.  */
  35 #define ERROR_RETURN                                                          \
  36   do {                                                                        \
  37     __set_errno (EINVAL);                                                     \
  38     return NULL;                                                              \
  39   } while (0)
  40
  41
  42 __locale_t
  43 __newlocale (int category_mask, const char *locale, __locale_t base)
  44 {
  45   /* Intermediate memory for result.  */
  46   const char *newnames[__LC_LAST];
  47   struct __locale_struct result;
  48   __locale_t result_ptr;
  49   char *locale_path;
  50   size_t locale_path_len;
  51   const char *locpath_var;
  52   int cnt;
  53   size_t names_len;
  54
  55   /* We treat LC_ALL in the same way as if all bits were set.  */
  56   if (category_mask == 1 << LC_ALL)
  57     category_mask = (1 << __LC_LAST) - 1 - (1 << LC_ALL);
  58
  59   /* Sanity check for CATEGORY argument.  */
  60   if ((category_mask & ~((1 << __LC_LAST) - 1 - (1 << LC_ALL))) != 0)
  61     ERROR_RETURN;
  62
  63   /* `newlocale' does not support asking for the locale name. */
  64   if (locale == NULL)
  65     ERROR_RETURN;
  66
  67   if (base == _nl_C_locobj_ptr)
  68     /* We're to modify BASE, returned for a previous call with "C".
  69        We can't really modify the read-only structure, so instead
  70        start over by copying it.  */
  71     base = NULL;
  72
  73   if ((base == NULL || category_mask == (1 << __LC_LAST) - 1 - (1 << LC_ALL))
  74       && (category_mask == 0 || !strcmp (locale, "C")))
  75     /* Asking for the "C" locale needn't allocate a new object.  */
  76     return _nl_C_locobj_ptr;
  77
  78   /* Allocate memory for the result.  */
  79   if (base != NULL)
  80     result = *base;
  81   else
  82     /* Fill with pointers to C locale data.  */
  83     result = _nl_C_locobj;
  84
  85   /* If no category is to be set we return BASE if available or a
  86      dataset using the C locale data.  */
  87   if (category_mask == 0)
  88     {
  89       result_ptr = (__locale_t) malloc (sizeof (struct __locale_struct));
  90       if (result_ptr == NULL)
  91         return NULL;
  92       *result_ptr = result;
  93
  94       goto update;
  95     }
  96
  97   /* We perhaps really have to load some data.  So we determine the
  98      path in which to look for the data now.  The environment variable
  99      `LOCPATH' must only be used when the binary has no SUID or SGID
 100      bit set.  If using the default path, we tell _nl_find_locale
 101      by passing null and it can check the canonical locale archive.  */
 102   locale_path = NULL;
 103   locale_path_len = 0;
 104
 105   locpath_var = getenv ("LOCPATH");
 106   if (locpath_var != NULL && locpath_var[0] != '\0')
 107     {
 108       if (__argz_create_sep (locpath_var, ':',
 109                              &locale_path, &locale_path_len) != 0)
 110         return NULL;
 111
 112       if (__argz_add_sep (&locale_path, &locale_path_len,
 113                           _nl_default_locale_path, ':') != 0)
 114         return NULL;
 115     }
 116
 117   /* Get the names for the locales we are interested in.  We either
 118      allow a composite name or a single name.  */
 119   for (cnt = 0; cnt < __LC_LAST; ++cnt)
 120     if (cnt != LC_ALL)
 121       newnames[cnt] = locale;
 122   if (strchr (locale, ';') != NULL)
 123     {
 124       /* This is a composite name.  Make a copy and split it up.  */
 125       char *np = strdupa (locale);
 126       char *cp;
 127       int specified_mask = 0;
 128
 129       while ((cp = strchr (np, '=')) != NULL)
 130         {
 131           for (cnt = 0; cnt < __LC_LAST; ++cnt)
 132             if (cnt != LC_ALL
 133                 && (size_t) (cp - np) == _nl_category_name_sizes[cnt]
 134                 && memcmp (np, (_nl_category_names.str
 135                                 + _nl_category_name_idxs[cnt]), cp - np) == 0)
 136               break;
 137
 138           if (cnt == __LC_LAST)
 139             /* Bogus category name.  */
 140             ERROR_RETURN;
 141
 142           /* Found the category this clause sets.  */
 143           specified_mask |= 1 << cnt;
 144           newnames[cnt] = ++cp;
 145           cp = strchr (cp, ';');
 146           if (cp != NULL)
 147             {
 148               /* Examine the next clause.  */
 149               *cp = '\0';
 150               np = cp + 1;
 151             }
 152           else
 153             /* This was the last clause.  We are done.  */
 154             break;
 155         }
 156
 157       if (category_mask &~ specified_mask)
 158         /* The composite name did not specify all categories we need.  */
 159         ERROR_RETURN;
 160     }
 161
 162   /* Protect global data.  */
 163   __libc_rwlock_wrlock (__libc_setlocale_lock);
 164
 165   /* Now process all categories we are interested in.  */
 166   names_len = 0;
 167   for (cnt = 0; cnt < __LC_LAST; ++cnt)
 168     {
 169       if ((category_mask & 1 << cnt) != 0)
 170         {
 171           result.__locales[cnt] = _nl_find_locale (locale_path,
 172                                                    locale_path_len,
 173                                                    cnt, &newnames[cnt]);
 174           if (result.__locales[cnt] == NULL)
 175             {
 176             free_cnt_data_and_exit:
 177               while (cnt-- > 0)
 178                 if (((category_mask & 1 << cnt) != 0)
 179                     && result.__locales[cnt]->usage_count != UNDELETABLE)
 180                   /* We can remove the data.  */
 181                   _nl_remove_locale (cnt, result.__locales[cnt]);
 182
 183               /* Critical section left.  */
 184               __libc_rwlock_unlock (__libc_setlocale_lock);
 185               return NULL;
 186             }
 187
 188           if (newnames[cnt] != _nl_C_name)
 189             names_len += strlen (newnames[cnt]) + 1;
 190         }
 191       else if (cnt != LC_ALL && result.__names[cnt] != _nl_C_name)
 192         /* Tally up the unchanged names from BASE as well.  */
 193         names_len += strlen (result.__names[cnt]) + 1;
 194     }
 195
 196   /* We successfully loaded all required data.  Allocate a new structure.
 197      We can't just reuse the BASE pointer, because the name strings are
 198      changing and we need the old name string area intact so we can copy
 199      out of it into the new one without overlap problems should some
 200      category's name be getting longer.  */
 201   result_ptr = malloc (sizeof (struct __locale_struct) + names_len);
 202   if (result_ptr == NULL)
 203     {
 204       cnt = __LC_LAST;
 205       goto free_cnt_data_and_exit;
 206     }
 207
 208   if (base == NULL)
 209     {
 210       /* Fill in this new structure from scratch.  */
 211
 212       char *namep = (char *) (result_ptr + 1);
 213
 214       /* Install copied new names in the new structure's __names array.
 215          If resolved to "C", that is already in RESULT.__names to start.  */
 216       for (cnt = 0; cnt < __LC_LAST; ++cnt)
 217         if ((category_mask & 1 << cnt) != 0 && newnames[cnt] != _nl_C_name)
 218           {
 219             result.__names[cnt] = namep;
 220             namep = __stpcpy (namep, newnames[cnt]) + 1;
 221           }
 222
 223       *result_ptr = result;
 224     }
 225   else
 226     {
 227       /* We modify the base structure.  */
 228
 229       char *namep = (char *) (result_ptr + 1);
 230
 231       for (cnt = 0; cnt < __LC_LAST; ++cnt)
 232         if ((category_mask & 1 << cnt) != 0)
 233           {
 234             if (base->__locales[cnt]->usage_count != UNDELETABLE)
 235               /* We can remove the old data.  */
 236               _nl_remove_locale (cnt, base->__locales[cnt]);
 237             result_ptr->__locales[cnt] = result.__locales[cnt];
 238
 239             if (newnames[cnt] == _nl_C_name)
 240               result_ptr->__names[cnt] = _nl_C_name;
 241             else
 242               {
 243                 result_ptr->__names[cnt] = namep;
 244                 namep = __stpcpy (namep, newnames[cnt]) + 1;
 245               }
 246           }
 247         else if (cnt != LC_ALL)
 248           {
 249             /* The RESULT members point into the old BASE structure.  */
 250             result_ptr->__locales[cnt] = result.__locales[cnt];
 251             if (result.__names[cnt] == _nl_C_name)
 252               result_ptr->__names[cnt] = _nl_C_name;
 253             else
 254               {
 255                 result_ptr->__names[cnt] = namep;
 256                 namep = __stpcpy (namep, result.__names[cnt]) + 1;
 257               }
 258           }
 259
 260       free (base);
 261     }
 262
 263   /* Critical section left.  */
 264   __libc_rwlock_unlock (__libc_setlocale_lock);
 265
 266   /* Update the special members.  */
 267  update:
 268   {
 269     union locale_data_value *ctypes = result_ptr->__locales[LC_CTYPE]->values;
 270     result_ptr->__ctype_b = (const unsigned short int *)
 271       ctypes[_NL_ITEM_INDEX (_NL_CTYPE_CLASS)].string + 128;
 272     result_ptr->__ctype_tolower = (const int *)
 273       ctypes[_NL_ITEM_INDEX (_NL_CTYPE_TOLOWER)].string + 128;
 274     result_ptr->__ctype_toupper = (const int *)
 275       ctypes[_NL_ITEM_INDEX (_NL_CTYPE_TOUPPER)].string + 128;
 276   }
 277
 278   return result_ptr;
 279 }
 280 weak_alias (__newlocale, newlocale)