1 /* $NetBSD: safe.c,v 1.3 2014/12/10 04:37:59 christos Exp $ */
2
3 /*
4 * Copyright (C) 2013 Internet Systems Consortium, Inc. ("ISC")
5 *
6 * Permission to use, copy, modify, and/or distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
11 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
12 * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
13 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
14 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
15 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
16 * PERFORMANCE OF THIS SOFTWARE.
17 */
18
19 /* Id */
20
21 /*! \file */
22
23 #include <config.h>
24
25 #include <isc/safe.h>
26 #include <isc/util.h>
27
28 #ifdef _MSC_VER
29 #pragma optimize("", off)
30 #endif
31
32 isc_boolean_t
isc_safe_memcmp(const void * s1,const void * s2,size_t n)33 isc_safe_memcmp(const void *s1, const void *s2, size_t n) {
34 isc_uint8_t acc = 0;
35
36 if (n != 0U) {
37 const isc_uint8_t *p1 = s1, *p2 = s2;
38
39 do {
40 acc |= *p1++ ^ *p2++;
41 } while (--n != 0U);
42 }
43 return (ISC_TF(acc == 0));
44 }
45