lib/uninorm/u-normxfrm.h

   1 /* Locale dependent transformation for comparison of Unicode strings.
   2    Copyright (C) 2009-2019 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 char *
  19 FUNC (const UNIT *s, size_t n, uninorm_t nf,
  20       char *resultbuf, size_t *lengthp)
  21 {
  22   UNIT normsbuf[2048 / sizeof (UNIT)];
  23   UNIT *norms;
  24   size_t norms_length;
  25   char convsbuf[2048];
  26   char *convs;
  27   size_t convs_length;
  28   char *result;
  29
  30   /* Normalize the Unicode string.  */
  31   norms_length = sizeof (normsbuf) / sizeof (UNIT);
  32   norms = U_NORMALIZE (nf, s, n, normsbuf, &norms_length);
  33   if (norms == NULL)
  34     /* errno is set here.  */
  35     return NULL;
  36
  37   /* Convert it to locale encoding.  */
  38   convs_length = sizeof (convsbuf) - 1;
  39   convs = U_CONV_TO_ENCODING (locale_charset (),
  40                               iconveh_error,
  41                               norms, norms_length,
  42                               NULL,
  43                               convsbuf, &convs_length);
  44   if (convs == NULL)
  45     {
  46       if (norms != normsbuf)
  47         {
  48           int saved_errno = errno;
  49           free (norms);
  50           errno = saved_errno;
  51         }
  52       return NULL;
  53     }
  54
  55   if (norms != normsbuf)
  56     free (norms);
  57
  58   /* Ensure one more byte is available.  */
  59   if (convs != convsbuf)
  60     {
  61       char *memory = (char *) realloc (convs, convs_length + 1);
  62       if (memory == NULL)
  63         {
  64           free (convs);
  65           errno = ENOMEM;
  66           return NULL;
  67         }
  68       convs = memory;
  69     }
  70
  71   /* Apply locale dependent transformations for comparison.  */
  72   result = amemxfrm (convs, convs_length, resultbuf, lengthp);
  73   if (result == NULL)
  74     {
  75       if (convs != convsbuf)
  76         {
  77           int saved_errno = errno;
  78           free (convs);
  79           errno = saved_errno;
  80         }
  81       return NULL;
  82     }
  83
  84   if (convs != convsbuf)
  85     free (convs);
  86   return result;
  87 }