locale/newlocale.c

   1 /* Return a reference to locale information record.
   2    Copyright (C) 1996, 1997 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 Library General Public License as
   8    published by the Free Software Foundation; either version 2 of the
   9    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    Library General Public License for more details.
  15
  16    You should have received a copy of the GNU Library General Public
  17    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  18    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include <argz.h>
  22 #include <errno.h>
  23 #include <locale.h>
  24 #include <stdlib.h>
  25
  26 #include "localeinfo.h"
  27
  28
  29 /* Constant data defined in setlocale.c.  */
  30 extern struct locale_data *const _nl_C[];
  31
  32 /* Use this when we come along an error.  */
  33 #define ERROR_RETURN                                                          \
  34   do {                                                                        \
  35     __set_errno (EINVAL);                                                     \
  36     return NULL;                                                              \
  37   } while (0)
  38
  39
  40 __locale_t
  41 __newlocale (int category_mask, const char *locale, __locale_t base)
  42 {
  43   /* Intermediate memory for result.  */
  44   const char *newnames[LC_ALL];
  45   struct __locale_struct result;
  46   __locale_t result_ptr;
  47   char *locale_path;
  48   size_t locale_path_len;
  49   const char *locpath_var;
  50   int cnt;
  51
  52   /* We treat LC_ALL in the same way as if all bits were set.  */
  53   if (category_mask == LC_ALL)
  54     category_mask = (1 << LC_ALL) - 1;
  55
  56   /* Sanity check for CATEGORY argument.  */
  57   if ((category_mask & ~(1 << LC_ALL) - 1) != 0)
  58     ERROR_RETURN;
  59
  60   /* `newlocale' does not support asking for the locale name. */
  61   if (locale == NULL)
  62     ERROR_RETURN;
  63
  64   /* Allocate memory for the result.  */
  65   if (base != NULL)
  66     {
  67       if (base != NULL)
  68         return base;
  69
  70       result = *base;
  71     }
  72   else
  73     {
  74       /* Fill with pointers to C locale data to .  */
  75       for (cnt = 0; cnt < LC_ALL; ++cnt)
  76         result.__locales[cnt] = _nl_C[cnt];
  77
  78       /* If no category is to be set we return BASE if available or a
  79          dataset using the C locale data.  */
  80       if (category_mask == 0)
  81         {
  82           result_ptr = (__locale_t) malloc (sizeof (struct __locale_struct));
  83           *result_ptr = result;
  84
  85           goto update;
  86         }
  87     }
  88
  89   /* We perhaps really have to load some data.  So we determine the
  90      path in which to look for the data now.  The environment variable
  91      `LOCPATH' must only be used when the binary has no SUID or SGID
  92      bit set.  */
  93   locale_path = NULL;
  94   locale_path_len = 0;
  95
  96   locpath_var = __secure_getenv ("LOCPATH");
  97   if (locpath_var != NULL && locpath_var[0] != '\0')
  98     if (__argz_create_sep (locpath_var, ':',
  99                            &locale_path, &locale_path_len) != 0)
 100       return NULL;
 101
 102   if (__argz_append (&locale_path, &locale_path_len,
 103                      LOCALE_PATH, sizeof (LOCALE_PATH)) != 0)
 104     return NULL;
 105
 106   /* Get the names for the locales we are interested in.  We either
 107      allow a composite name or a single name.  */
 108   for (cnt = 0; cnt < LC_ALL; ++cnt)
 109     newnames[cnt] = locale;
 110   if (strchr (locale, ';') != NULL)
 111     {
 112       /* This is a composite name.  Make a copy and split it up.  */
 113       char *np = strdupa (locale);
 114       char *cp;
 115
 116       while ((cp = strchr (np, '=')) != NULL)
 117         {
 118           for (cnt = 0; cnt < LC_ALL; ++cnt)
 119             if ((size_t) (cp - np) == _nl_category_name_sizes[cnt]
 120                 && memcmp (np, _nl_category_names[cnt], cp - np) == 0)
 121               break;
 122
 123           if (cnt == LC_ALL)
 124             /* Bogus category name.  */
 125             ERROR_RETURN;
 126
 127           /* Found the category this clause sets.  */
 128           newnames[cnt] = ++cp;
 129           cp = strchr (cp, ';');
 130           if (cp != NULL)
 131             {
 132               /* Examine the next clause.  */
 133               *cp = '\0';
 134               np = cp + 1;
 135             }
 136           else
 137             /* This was the last clause.  We are done.  */
 138             break;
 139         }
 140
 141       for (cnt = 0; cnt < LC_ALL; ++cnt)
 142         if ((category_mask & 1 << cnt) != 0 && newnames[cnt] == locale)
 143           /* The composite name did not specify the category we need.  */
 144           ERROR_RETURN;
 145     }
 146
 147   /* Now process all categories we are interested in.  */
 148   for (cnt = 0; cnt < LC_ALL; ++cnt)
 149     if ((category_mask & 1 << cnt) != 0)
 150       {
 151         result.__locales[cnt] = _nl_find_locale (locale_path, locale_path_len,
 152                                                  cnt, &newnames[cnt]);
 153         if (result.__locales[cnt] == NULL)
 154           return NULL;
 155       }
 156
 157   /* We successfully loaded all required data.  */
 158   if (base == NULL)
 159     {
 160       /* Allocate new structure.  */
 161       result_ptr = (__locale_t) malloc (sizeof (struct __locale_struct));
 162       if (result_ptr == NULL)
 163         return NULL;
 164
 165       *result_ptr = result;
 166     }
 167   else
 168     *(result_ptr = base) = result;
 169
 170   /* Update the special members.  */
 171  update:
 172   {
 173     union locale_data_value *ctypes = result_ptr->__locales[LC_CTYPE]->values;
 174   result_ptr->__ctype_b = (const unsigned short int *)
 175     (ctypes[_NL_ITEM_INDEX (_NL_CTYPE_CLASS)] .string);
 176 #if BYTE_ORDER == BIG_ENDIAN
 177   result_ptr->__ctype_tolower = (const int *)
 178     (ctypes[_NL_ITEM_INDEX (_NL_CTYPE_TOLOWER_EB)].string);
 179   result_ptr->__ctype_toupper = (const int *)
 180     (ctypes[_NL_ITEM_INDEX (_NL_CTYPE_TOUPPER_EB)].string);
 181 #elif BYTE_ORDER == LITTLE_ENDIAN
 182   result_ptr->__ctype_tolower = (const int *)
 183     (ctypes[_NL_ITEM_INDEX (_NL_CTYPE_TOLOWER_EL)].string);
 184   result_ptr->__ctype_toupper = (const int *)
 185     (ctypes[_NL_ITEM_INDEX (_NL_CTYPE_TOUPPER_EL)].string);
 186 #else
 187 #error bizarre byte order
 188 #endif
 189   }
 190
 191   return result_ptr;
 192 }