wcsmbs/wcsncase.c

   1 /* Compare at most N wide characters of two strings without taking care
   2    for the case.
   3    Copyright (C) 1992, 1996, 1997 Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Library General Public License as
   8    published by the Free Software Foundation; either version 2 of the
   9    License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Library General Public License for more details.
  15
  16    You should have received a copy of the GNU Library General Public
  17    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  18    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include <wchar.h>
  22 #include <wctype.h>
  23
  24 #ifndef weak_alias
  25 # define __wcsncasecmp wcsncasecmp
  26 #endif
  27
  28 /* Compare no more than N wide characters of S1 and S2,
  29    ignoring case, returning less than, equal to or
  30    greater than zero if S1 is lexicographically less
  31    than, equal to or greater than S2.  */
  32 int
  33 __wcsncasecmp (s1, s2, n)
  34      const wchar_t *s1;
  35      const wchar_t *s2;
  36      size_t n;
  37 {
  38   wint_t c1, c2;
  39
  40   if (s1 == s2 || n == 0)
  41     return 0;
  42
  43   do
  44     {
  45       c1 = (wint_t) towlower (*s1++);
  46       c2 = (wint_t) towlower (*s2++);
  47       if (c1 == L'\0' || c1 != c2)
  48         return c1 - c2;
  49     } while (--n > 0);
  50
  51   return c1 - c2;
  52 }
  53 #ifdef weak_alias
  54 weak_alias (__wcsncasecmp, wcsncasecmp)
  55 #endif