9.4 Example 4

This example demonstrates how the library is used to convert ASCII compatible names to internationalized domain names.

/* example4.c --- Example ToUnicode() code showing how to use Libidn.
 * Copyright (C) 2002, 2003, 2004, 2006  Simon Josefsson
 *
 * This file is part of GNU Libidn.
 *
 * GNU Libidn is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * GNU Libidn is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with GNU Libidn; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <locale.h>		/* setlocale() */
#include <stringprep.h>		/* stringprep_locale_charset() */
#include <idna.h>		/* idna_to_unicode_lzlz() */

/*
 * Compiling using libtool and pkg-config is recommended:
 *
 * $ libtool cc -o example4 example4.c `pkg-config --cflags --libs libidn`
 * $ ./example4
 * Input domain encoded as `ISO-8859-1': www.xn--rksmrgsa-0zap8p.example
 * Read string (length 33): 77 77 77 2e 78 6e 2d 2d 72 6b 73 6d 72 67 73 61 2d 30 7a 61 70 38 70 2e 65 78 61 6d 70 6c 65
 * ACE label (length 23): 'www.räksmörgåsa.example'
 * 77 77 77 2e 72 e4 6b 73 6d f6 72 67 e5 73 61 2e 65 78 61 6d 70 6c 65
 * $
 *
 */

int
main (int argc, char *argv[])
{
  char buf[BUFSIZ];
  char *p;
  int rc;
  size_t i;

  setlocale (LC_ALL, "");

  printf ("Input domain encoded as `%s': ", stringprep_locale_charset ());
  fflush (stdout);
  fgets (buf, BUFSIZ, stdin);
  buf[strlen (buf) - 1] = '\0';

  printf ("Read string (length %d): ", strlen (buf));
  for (i = 0; i < strlen (buf); i++)
    printf ("%02x ", buf[i] & 0xFF);
  printf ("\n");

  rc = idna_to_unicode_lzlz (buf, &p, 0);
  if (rc != IDNA_SUCCESS)
    {
      printf ("ToUnicode() failed (%d): %s\n", rc, idna_strerror (rc));
      exit (1);
    }

  printf ("ACE label (length %d): '%s'\n", strlen (p), p);
  for (i = 0; i < strlen (p); i++)
    printf ("%02x ", p[i] & 0xFF);
  printf ("\n");

  free (p);

  return 0;
}