locale/newlocale.c

   1 /* Return a reference to locale information record.
   2    Copyright (C) 1996-2020 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    <https://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_get (cnt)), cp - np) == 0)
 135               break;
 136
 137           if (cnt == __LC_LAST)
 138             /* Bogus category name.  */
 139             ERROR_RETURN;
 140
 141           /* Found the category this clause sets.  */
 142           specified_mask |= 1 << cnt;
 143           newnames[cnt] = ++cp;
 144           cp = strchr (cp, ';');
 145           if (cp != NULL)
 146             {
 147               /* Examine the next clause.  */
 148               *cp = '\0';
 149               np = cp + 1;
 150             }
 151           else
 152             /* This was the last clause.  We are done.  */
 153             break;
 154         }
 155
 156       if (category_mask &~ specified_mask)
 157         /* The composite name did not specify all categories we need.  */
 158         ERROR_RETURN;
 159     }
 160
 161   /* Protect global data.  */
 162   __libc_rwlock_wrlock (__libc_setlocale_lock);
 163
 164   /* Now process all categories we are interested in.  */
 165   names_len = 0;
 166   for (cnt = 0; cnt < __LC_LAST; ++cnt)
 167     {
 168       if ((category_mask & 1 << cnt) != 0)
 169         {
 170           result.__locales[cnt] = _nl_find_locale (locale_path,
 171                                                    locale_path_len,
 172                                                    cnt, &newnames[cnt]);
 173           if (result.__locales[cnt] == NULL)
 174             {
 175             free_cnt_data_and_exit:
 176               while (cnt-- > 0)
 177                 if (((category_mask & 1 << cnt) != 0)
 178                     && result.__locales[cnt]->usage_count != UNDELETABLE)
 179                   /* We can remove the data.  */
 180                   _nl_remove_locale (cnt, result.__locales[cnt]);
 181
 182               /* Critical section left.  */
 183               __libc_rwlock_unlock (__libc_setlocale_lock);
 184               return NULL;
 185             }
 186
 187           if (newnames[cnt] != _nl_C_name)
 188             names_len += strlen (newnames[cnt]) + 1;
 189         }
 190       else if (cnt != LC_ALL && result.__names[cnt] != _nl_C_name)
 191         /* Tally up the unchanged names from BASE as well.  */
 192         names_len += strlen (result.__names[cnt]) + 1;
 193     }
 194
 195   /* We successfully loaded all required data.  Allocate a new structure.
 196      We can't just reuse the BASE pointer, because the name strings are
 197      changing and we need the old name string area intact so we can copy
 198      out of it into the new one without overlap problems should some
 199      category's name be getting longer.  */
 200   result_ptr = malloc (sizeof (struct __locale_struct) + names_len);
 201   if (result_ptr == NULL)
 202     {
 203       cnt = __LC_LAST;
 204       goto free_cnt_data_and_exit;
 205     }
 206
 207   if (base == NULL)
 208     {
 209       /* Fill in this new structure from scratch.  */
 210
 211       char *namep = (char *) (result_ptr + 1);
 212
 213       /* Install copied new names in the new structure's __names array.
 214          If resolved to "C", that is already in RESULT.__names to start.  */
 215       for (cnt = 0; cnt < __LC_LAST; ++cnt)
 216         if ((category_mask & 1 << cnt) != 0 && newnames[cnt] != _nl_C_name)
 217           {
 218             result.__names[cnt] = namep;
 219             namep = __stpcpy (namep, newnames[cnt]) + 1;
 220           }
 221
 222       *result_ptr = result;
 223     }
 224   else
 225     {
 226       /* We modify the base structure.  */
 227
 228       char *namep = (char *) (result_ptr + 1);
 229
 230       for (cnt = 0; cnt < __LC_LAST; ++cnt)
 231         if ((category_mask & 1 << cnt) != 0)
 232           {
 233             if (base->__locales[cnt]->usage_count != UNDELETABLE)
 234               /* We can remove the old data.  */
 235               _nl_remove_locale (cnt, base->__locales[cnt]);
 236             result_ptr->__locales[cnt] = result.__locales[cnt];
 237
 238             if (newnames[cnt] == _nl_C_name)
 239               result_ptr->__names[cnt] = _nl_C_name;
 240             else
 241               {
 242                 result_ptr->__names[cnt] = namep;
 243                 namep = __stpcpy (namep, newnames[cnt]) + 1;
 244               }
 245           }
 246         else if (cnt != LC_ALL)
 247           {
 248             /* The RESULT members point into the old BASE structure.  */
 249             result_ptr->__locales[cnt] = result.__locales[cnt];
 250             if (result.__names[cnt] == _nl_C_name)
 251               result_ptr->__names[cnt] = _nl_C_name;
 252             else
 253               {
 254                 result_ptr->__names[cnt] = namep;
 255                 namep = __stpcpy (namep, result.__names[cnt]) + 1;
 256               }
 257           }
 258
 259       free (base);
 260     }
 261
 262   /* Critical section left.  */
 263   __libc_rwlock_unlock (__libc_setlocale_lock);
 264
 265   /* Update the special members.  */
 266  update:
 267   {
 268     union locale_data_value *ctypes = result_ptr->__locales[LC_CTYPE]->values;
 269     result_ptr->__ctype_b = (const unsigned short int *)
 270       ctypes[_NL_ITEM_INDEX (_NL_CTYPE_CLASS)].string + 128;
 271     result_ptr->__ctype_tolower = (const int *)
 272       ctypes[_NL_ITEM_INDEX (_NL_CTYPE_TOLOWER)].string + 128;
 273     result_ptr->__ctype_toupper = (const int *)
 274       ctypes[_NL_ITEM_INDEX (_NL_CTYPE_TOUPPER)].string + 128;
 275   }
 276
 277   return result_ptr;
 278 }
 279 weak_alias (__newlocale, newlocale)