summary refs log tree commit diff
path: root/wcsmbs/wcwidth.h
blob: 1d2c7b084c71bc2bdbe3f39512f22f1093adc1dd (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
/* Internal header containing implementation of wcwidth() function.
   Copyright (C) 1996-2017 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1996.

   The GNU C Library 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.

   The GNU C Library 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 the GNU C Library; if not, see
   <http://www.gnu.org/licenses/>.  */

#include <wchar.h>
#include <wctype.h>
#include "../wctype/wchar-lookup.h"
#include "../locale/localeinfo.h"

/* Table containing width information.  */
extern const char *__ctype32_width attribute_hidden;

static __inline int
internal_wcwidth (wchar_t wc)
{
  unsigned char res;

  /* The tables have been prepared in such a way that
     1. wc == L'\0' yields res = 0,
     2. !iswprint (wc) implies res = '\xff'.  */
  res = wcwidth_table_lookup (_NL_CURRENT (LC_CTYPE, _NL_CTYPE_WIDTH), wc);

  return res == (unsigned char) '\xff' ? -1 : (int) res;
}