xref: /freebsd/contrib/openpam/lib/libpam/openpam_strlcmp.h (revision 389e4940069316fe667ffa263fa7d6390d0a960f)
1 /*-
2  * Copyright (c) 2011 Dag-Erling Smørgrav
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. The name of the author may not be used to endorse or promote
14  *    products derived from this software without specific prior written
15  *    permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $OpenPAM: openpam_strlcmp.h 938 2017-04-30 21:34:42Z des $
30  */
31 
32 #ifndef OPENPAM_STRLCMP_H_INCLUDED
33 #define OPENPAM_STRLCMP_H_INCLUDED
34 
35 #ifndef HAVE_STRLCMP
36 /* like strcmp(3), but verifies that the entirety of s1 was matched */
37 static int
38 strlcmp(const char *s1, const char *s2, size_t len)
39 {
40 
41 	for (; len && *s1 && *s2; --len, ++s1, ++s2)
42 		if (*s1 != *s2)
43 			return ((unsigned char)*s1 - (unsigned char)*s2);
44 	return ((unsigned char)*s1);
45 }
46 #endif
47 
48 #endif
49