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 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