xref: /freebsd/lib/libc/secure/snprintf_chk.c (revision e9ac41698b2f322d55ccf9da50a3596edb2c1800)
1 /*-
2  *
3  * SPDX-License-Identifier: BSD-2-Clause
4  *
5  * Copyright (c) 2006 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by Christos Zoulas.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 #include <sys/cdefs.h>
33 __RCSID("$NetBSD: snprintf_chk.c,v 1.5 2008/04/28 20:23:00 martin Exp $");
34 
35 #include <stdarg.h>
36 #include <stdio.h>
37 
38 #include <ssp/stdio.h>
39 #undef vsnprintf
40 
41 int
42 __snprintf_chk(char * __restrict buf, size_t len, int flags, size_t slen,
43     const char * __restrict fmt, ...)
44 {
45 	va_list ap;
46 	int rv;
47 
48 	if (len > slen)
49 		__chk_fail();
50 
51 	va_start(ap, fmt);
52 	rv = vsnprintf(buf, len, fmt, ap);
53 	va_end(ap);
54 
55 	return (rv);
56 }
57