view lib/wcsncmp-impl.h @ 14290:0da9f0fe36fe

New module 'wcsncmp'. * modules/wcsncmp: New file. * lib/wchar.in.h (wcsncmp): New declaration. * lib/wcsncmp.c: New file. * lib/wcsncmp-impl.h: New file, from libutf8 with modifications. * m4/wcsncmp.m4: New file. * m4/wchar_h.m4 (gl_WCHAR_H): Test whether wcsncmp is declared. (gl_WCHAR_H_DEFAULTS): Initialize GNULIB_WCSNCMP, HAVE_WCSNCMP. * modules/wchar (Makefile.am): Substitute GNULIB_WCSNCMP, HAVE_WCSNCMP. * tests/test-wchar-c++.cc: Test the declaration of wcsncmp. * doc/posix-functions/wcsncmp.texi: Mention the new module.
author Bruno Haible <bruno@clisp.org>
date Sun, 06 Feb 2011 04:47:49 +0100 (2011-02-06)
parents
children 8250f2777afc
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/* Compare two wide strings.
   Copyright (C) 1999, 2011 Free Software Foundation, Inc.
   Written by Bruno Haible <bruno@clisp.org>, 1999.

   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

int
wcsncmp (const wchar_t *s1, const wchar_t *s2, size_t n)
{
  for (; n > 0;)
    {
      wchar_t wc1 = *s1++;
      wchar_t wc2 = *s2++;
      if (wc1 != (wchar_t)'\0' && wc1 == wc2)
        {
          n--;
          continue;
        }
      /* Note that wc1 and wc2 each have at most 31 bits.  */
      return (int)wc1 - (int)wc2;
             /* > 0 if wc1 > wc2, < 0 if wc1 < wc2,
                = 0 if wc1 and wc2 are both '\0'.  */
    }
  return 0;
}