NetBSD/gnu/dist/texinfo/lib/strncasecmp.c

49 lines
1.5 KiB
C

/* strncase.c -- compare at most N characters of two strings without
taking care for the case
Copyright (C) 1992 Free Software Foundation.
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 2, 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, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#include <string.h>
#include <ctype.h>
/* Compare no more than N characters of S1 and S2,
ignoring case, returning less than, equal to or
greater than zero if S1 is lexicographically less
than, equal to or greater than S2. */
int
strncasecmp (s1, s2, n)
const char *s1;
const char *s2;
size_t n;
{
register const unsigned char *p1 = (const unsigned char *) s1;
register const unsigned char *p2 = (const unsigned char *) s2;
unsigned char c1, c2;
if (p1 == p2 || n == 0)
return 0;
do
{
c1 = tolower (*p1++);
c2 = tolower (*p2++);
if (c1 == '\0' || c1 != c2)
return c1 - c2;
} while (--n > 0);
return c1 - c2;
}