lib/unicase/ulc-casexfrm.c

   1 /* Locale dependent transformation for case insensitive comparison of strings.
   2    Copyright (C) 2009-2018 Free Software Foundation, Inc.
   3    Written by Bruno Haible <bruno@clisp.org>, 2009.
   4
   5    This program is free software: you can redistribute it and/or modify it
   6    under the terms of the GNU Lesser General Public License as published
   7    by the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public License
  16    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  17
  18 #include <config.h>
  19
  20 /* Specification.  */
  21 #include "unicase.h"
  22
  23 #include <errno.h>
  24 #include <stdlib.h>
  25
  26 #include "uniconv.h"
  27
  28 char *
  29 ulc_casexfrm (const char *s, size_t n, const char *iso639_language,
  30               uninorm_t nf,
  31               char *resultbuf, size_t *lengthp)
  32 {
  33   uint8_t convbuf[2048 / sizeof (uint8_t)];
  34   uint8_t *conv;
  35   size_t conv_length;
  36   char *result;
  37
  38   /* Convert the string to UTF-8.  */
  39   conv_length = sizeof (convbuf) / sizeof (uint8_t);
  40   conv =
  41     u8_conv_from_encoding (locale_charset (), iconveh_error, s, n, NULL,
  42                            convbuf, &conv_length);
  43   if (conv == NULL)
  44     /* errno is set here.  */
  45     return NULL;
  46
  47   /* Case-fold and normalize.  */
  48   result = u8_casexfrm (conv, conv_length, iso639_language, nf,
  49                         resultbuf, lengthp);
  50   if (result == NULL)
  51     {
  52       if (conv != convbuf)
  53         {
  54           int saved_errno = errno;
  55           free (conv);
  56           errno = saved_errno;
  57         }
  58       return NULL;
  59     }
  60
  61   if (conv != convbuf)
  62     free (conv);
  63   return result;
  64 }