1/* Determine the number of screen columns needed for a character.
2   Copyright (C) 2006-2007, 2010-2014 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 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 General Public License for more details.
13
14   You should have received a copy of the GNU General Public License
15   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
16
17#include <config.h>
18
19/* Specification.  */
20#include <wchar.h>
21
22/* Get iswprint.  */
23#include <wctype.h>
24
25#include "localcharset.h"
26#include "streq.h"
27#include "uniwidth.h"
28
29int
30wcwidth (wchar_t wc)
31#undef wcwidth
32{
33  /* In UTF-8 locales, use a Unicode aware width function.  */
34  const char *encoding = locale_charset ();
35  if (STREQ_OPT (encoding, "UTF-8", 'U', 'T', 'F', '-', '8', 0, 0, 0 ,0))
36    {
37      /* We assume that in a UTF-8 locale, a wide character is the same as a
38         Unicode character.  */
39      return uc_width (wc, encoding);
40    }
41  else
42    {
43      /* Otherwise, fall back to the system's wcwidth function.  */
44#if HAVE_WCWIDTH
45      return wcwidth (wc);
46#else
47      return wc == 0 ? 0 : iswprint (wc) ? 1 : -1;
48#endif
49    }
50}
51