wcsmbs/wcswidth.c

   1 /* Copyright (C) 1996-2017 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1996.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library 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
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include "wcwidth.h"
  20
  21 /* Determine number of column positions required for first N wide
  22    characters (or fewer if S ends before this) in S.  */
  23 int
  24 wcswidth (const wchar_t *s, size_t n)
  25 {
  26   int result = 0;
  27
  28   while (n-- > 0 && *s != L'\0')
  29     {
  30       int now = internal_wcwidth (*s);
  31       if (now == -1)
  32         return -1;
  33       result += now;
  34       ++s;
  35     }
  36
  37   return result;
  38 }