gnulib/lib/unistr/u32-strncmp.c

/* Compare UTF-32 strings.
   Copyright (C) 1999, 2002, 2006, 2009-2020 Free Software Foundation, Inc.
   Written by Bruno Haible <bruno@clisp.org>, 2002.

   This program 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 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
   Lesser General Public License for more details.

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

#include <config.h>

/* Specification.  */
#include "unistr.h"

int
u32_strncmp (const uint32_t *s1, const uint32_t *s2, size_t n)
{
  for (; n > 0;)
    {
      uint32_t uc1 = *s1++;
      uint32_t uc2 = *s2++;
      if (uc1 != 0 && uc1 == uc2)
        {
          n--;
          continue;
        }
      /* Note that uc1 and uc2 each have at most 31 bits. */
      return (int)uc1 - (int)uc2;
      /* > 0 if uc1 > uc2, < 0 if uc1 < uc2, = 0 if uc1 and uc2 are both 0.  */
    }
  return 0;
}