lib/duplocale.c

   1 /* Duplicate a locale object.
   2    Copyright (C) 2009 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU Lesser General Public License as published by
   6    the Free Software Foundation; either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program 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
  12    GNU Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public License
  15    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Bruno Haible <bruno@clisp.org>, 2007.  */
  18
  19 #include <config.h>
  20
  21 /* Specification.  */
  22 #include <locale.h>
  23
  24 #include <errno.h>
  25 #include <langinfo.h>
  26 #include <string.h>
  27
  28 /* Work around an incorrect definition of the _NL_LOCALE_NAME macro in
  29    glibc < 2.12.
  30    See <http://sourceware.org/bugzilla/show_bug.cgi?id=10968>.  */
  31 #undef _NL_LOCALE_NAME
  32 #define _NL_LOCALE_NAME(category) _NL_ITEM ((category), _NL_ITEM_INDEX (-1))
  33
  34 #define SIZEOF(a) (sizeof(a) / sizeof(a[0]))
  35
  36 #undef duplocale
  37
  38 locale_t
  39 rpl_duplocale (locale_t locale)
  40 {
  41   /* Work around crash in the duplocale function in glibc < 2.12.
  42      See <http://sourceware.org/bugzilla/show_bug.cgi?id=10969>.  */
  43   if (locale == LC_GLOBAL_LOCALE)
  44     {
  45       /* Create a copy of the locale by fetching the name of each locale
  46          category, starting with LC_CTYPE.  */
  47       static struct { int cat; int mask; } categories[] =
  48         {
  49             { LC_NUMERIC,        LC_NUMERIC_MASK },
  50             { LC_TIME,           LC_TIME_MASK },
  51             { LC_COLLATE,        LC_COLLATE_MASK },
  52             { LC_MONETARY,       LC_MONETARY_MASK },
  53             { LC_MESSAGES,       LC_MESSAGES_MASK }
  54 #ifdef LC_PAPER
  55           , { LC_PAPER,          LC_PAPER_MASK }
  56 #endif
  57 #ifdef LC_NAME
  58           , { LC_NAME,           LC_NAME_MASK }
  59 #endif
  60 #ifdef LC_ADDRESS
  61           , { LC_ADDRESS,        LC_ADDRESS_MASK }
  62 #endif
  63 #ifdef LC_TELEPHONE
  64           , { LC_TELEPHONE,      LC_TELEPHONE_MASK }
  65 #endif
  66 #ifdef LC_MEASUREMENT
  67           , { LC_MEASUREMENT,    LC_MEASUREMENT_MASK }
  68 #endif
  69 #ifdef LC_IDENTIFICATION
  70           , { LC_IDENTIFICATION, LC_IDENTIFICATION_MASK }
  71 #endif
  72         };
  73       const char *base_name;
  74       locale_t base_copy;
  75       unsigned int i;
  76
  77       base_name = nl_langinfo (_NL_LOCALE_NAME (LC_CTYPE));
  78       if (base_name[0] == '\0')
  79         /* Fallback code for glibc < 2.4, which did not implement
  80            nl_langinfo (_NL_LOCALE_NAME (category)).  */
  81         base_name = setlocale (LC_CTYPE, NULL);
  82       base_copy = newlocale (LC_ALL_MASK, base_name, NULL);
  83       if (base_copy == NULL)
  84         return NULL;
  85
  86       for (i = 0; i < SIZEOF (categories); i++)
  87         {
  88           int category = categories[i].cat;
  89           int category_mask = categories[i].mask;
  90           const char *name = nl_langinfo (_NL_LOCALE_NAME (category));
  91           if (name[0] == '\0')
  92             /* Fallback code for glibc < 2.4, which did not implement
  93                nl_langinfo (_NL_LOCALE_NAME (category)).  */
  94             name = setlocale (category, NULL);
  95           if (strcmp (name, base_name) != 0)
  96             {
  97               locale_t copy = newlocale (category_mask, name, base_copy);
  98               if (copy == NULL)
  99                 {
 100                   int saved_errno = errno;
 101                   freelocale (base_copy);
 102                   errno = saved_errno;
 103                   return NULL;
 104                 }
 105               /* No need to call freelocale (base_copy) if copy != base_copy;
 106                  the newlocale function already takes care of doing it.  */
 107               base_copy = copy;
 108             }
 109         }
 110
 111       return base_copy;
 112     }
 113
 114   return duplocale (locale);
 115 }