1 /* 2 * Copyright (c) 2017 Juniper Networks. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23 * SUCH DAMAGE. 24 */ 25 26 /* 27 * Copyright 2018 Nexenta Systems, Inc. 28 */ 29 30 #include "lint.h" 31 32 #include <errno.h> 33 #include <stddef.h> 34 #include <stdint.h> 35 #include <string.h> 36 37 #include "libc.h" 38 39 /* __memset_vp is a volatile pointer to memset() function */ 40 static void *(*const volatile __memset_vp)(void *, int, size_t) = (memset); 41 42 /* ISO/IEC 9899:2011 K.3.7.4.1 */ 43 errno_t 44 memset_s(void *s, rsize_t smax, int c, rsize_t n) 45 { 46 errno_t ret; 47 rsize_t lim; 48 unsigned char v; 49 50 ret = EINVAL; 51 lim = n < smax ? n : smax; 52 v = (unsigned char)c; 53 if (s == NULL) { 54 __throw_constraint_handler_s("memset_s: s is NULL", ret); 55 } else if (smax > RSIZE_MAX) { 56 __throw_constraint_handler_s("memset_s: smax > RSIZE_MAX", 57 ret); 58 } else { 59 /* 60 * Both s and smax are valid, fill the memory buffer using 61 * memset() called through a volatile pointer to guarantee 62 * it will not be optimized away. 63 */ 64 (*__memset_vp)(s, v, lim); 65 66 if (n > RSIZE_MAX) { 67 __throw_constraint_handler_s("memset_s: n > RSIZE_MAX", 68 ret); 69 } else if (n > smax) { 70 __throw_constraint_handler_s("memset_s: n > smax", ret); 71 } else { 72 ret = 0; 73 } 74 } 75 return (ret); 76 } 77