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#define	__STDC_WANT_LIB_EXT1__	1
31
32#include "lint.h"
33
34#include <errno.h>
35#include <stddef.h>
36#include <stdint.h>
37#include <string.h>
38
39#include "libc.h"
40
41/* __memset_vp is a volatile pointer to memset() function */
42static void *(*const volatile __memset_vp)(void *, int, size_t) = (memset);
43
44/* ISO/IEC 9899:2011 K.3.7.4.1 */
45errno_t
46memset_s(void *s, rsize_t smax, int c, rsize_t n)
47{
48	errno_t ret;
49	rsize_t lim;
50	unsigned char v;
51
52	ret = EINVAL;
53	lim = n < smax ? n : smax;
54	v = (unsigned char)c;
55	if (s == NULL) {
56		__throw_constraint_handler_s("memset_s: s is NULL", ret);
57	} else if (smax > RSIZE_MAX) {
58		__throw_constraint_handler_s("memset_s: smax > RSIZE_MAX",
59		    ret);
60	} else {
61		/*
62		 * Both s and smax are valid, fill the memory buffer using
63		 * memset() called through a volatile pointer to guarantee
64		 * it will not be optimized away.
65		 */
66		(*__memset_vp)(s, v, lim);
67
68		if (n > RSIZE_MAX) {
69			__throw_constraint_handler_s("memset_s: n > RSIZE_MAX",
70			    ret);
71		} else if (n > smax) {
72			__throw_constraint_handler_s("memset_s: n > smax", ret);
73		} else {
74			ret = 0;
75		}
76	}
77	return (ret);
78}
79