locale/newlocale.c

   1 /* Return a reference to locale information record.
   2    Copyright (C) 1996, 1997, 1999, 2000, 2001 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_LAST];
  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 == 1 << LC_ALL)
  54     category_mask = (1 << __LC_LAST) - 1 - (1 << LC_ALL);
  55
  56   /* Sanity check for CATEGORY argument.  */
  57   if ((category_mask & ~((1 << __LC_LAST) - 1 - (1 << LC_ALL))) != 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     result = *base;
  67   else
  68     {
  69       /* Fill with pointers to C locale data.  */
  70       for (cnt = 0; cnt < __LC_LAST; ++cnt)
  71         if (cnt != LC_ALL)
  72           result.__locales[cnt] = _nl_C[cnt];
  73     }
  74
  75   /* If no category is to be set we return BASE if available or a
  76      dataset using the C locale data.  */
  77   if (category_mask == 0)
  78     {
  79       result_ptr = (__locale_t) malloc (sizeof (struct __locale_struct));
  80       if (result_ptr == NULL)
  81         return NULL;
  82       *result_ptr = result;
  83
  84       goto update;
  85     }
  86
  87   /* We perhaps really have to load some data.  So we determine the
  88      path in which to look for the data now.  The environment variable
  89      `LOCPATH' must only be used when the binary has no SUID or SGID
  90      bit set.  */
  91   locale_path = NULL;
  92   locale_path_len = 0;
  93
  94   locpath_var = getenv ("LOCPATH");
  95   if (locpath_var != NULL && locpath_var[0] != '\0')
  96     if (__argz_create_sep (locpath_var, ':',
  97                            &locale_path, &locale_path_len) != 0)
  98       return NULL;
  99
 100   if (__argz_append (&locale_path, &locale_path_len,
 101                      LOCALEDIR, sizeof (LOCALEDIR)) != 0)
 102     return NULL;
 103
 104   /* Get the names for the locales we are interested in.  We either
 105      allow a composite name or a single name.  */
 106   for (cnt = 0; cnt < __LC_LAST; ++cnt)
 107     if (cnt != LC_ALL)
 108       newnames[cnt] = locale;
 109   if (strchr (locale, ';') != NULL)
 110     {
 111       /* This is a composite name.  Make a copy and split it up.  */
 112       char *np = strdupa (locale);
 113       char *cp;
 114
 115       while ((cp = strchr (np, '=')) != NULL)
 116         {
 117           for (cnt = 0; cnt < __LC_LAST; ++cnt)
 118             if (cnt != LC_ALL
 119                 && (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_LAST)
 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_LAST; ++cnt)
 142         if (cnt != LC_ALL
 143             && (category_mask & 1 << cnt) != 0 && newnames[cnt] == locale)
 144           /* The composite name did not specify the category we need.  */
 145           ERROR_RETURN;
 146     }
 147
 148   /* Now process all categories we are interested in.  */
 149   for (cnt = 0; cnt < __LC_LAST; ++cnt)
 150     if (cnt != LC_ALL && (category_mask & 1 << cnt) != 0)
 151       {
 152         result.__locales[cnt] = _nl_find_locale (locale_path, locale_path_len,
 153                                                  cnt, &newnames[cnt]);
 154         if (result.__locales[cnt] == NULL)
 155           return NULL;
 156       }
 157
 158   /* We successfully loaded all required data.  */
 159   if (base == NULL)
 160     {
 161       /* Allocate new structure.  */
 162       result_ptr = (__locale_t) malloc (sizeof (struct __locale_struct));
 163       if (result_ptr == NULL)
 164         return NULL;
 165
 166       *result_ptr = result;
 167     }
 168   else
 169     *(result_ptr = base) = result;
 170
 171   /* Update the special members.  */
 172  update:
 173   {
 174     union locale_data_value *ctypes = result_ptr->__locales[LC_CTYPE]->values;
 175     result_ptr->__ctype_b = (const unsigned short int *)
 176       (ctypes[_NL_ITEM_INDEX (_NL_CTYPE_CLASS)].string);
 177     result_ptr->__ctype_tolower = (const int *)
 178       (ctypes[_NL_ITEM_INDEX (_NL_CTYPE_TOLOWER)].string);
 179     result_ptr->__ctype_toupper = (const int *)
 180       (ctypes[_NL_ITEM_INDEX (_NL_CTYPE_TOUPPER)].string);
 181   }
 182
 183   return result_ptr;
 184 }