xref: /freebsd/contrib/openbsm/compat/strlcpy.h (revision 2e3507c25e42292b45a5482e116d278f5515d04d)
1 /*
2  * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
17  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
18  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
19  * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
22  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
25  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  *
27  * dollar OpenBSD: strlcpy.c,v 1.4 1999/05/01 18:56:41 millert Exp dollar
28  */
29 
30 /*
31  * Copy src to string dst of size siz.  At most siz-1 characters
32  * will be copied.  Always NUL terminates (unless siz == 0).
33  * Returns strlen(src); if retval >= siz, truncation occurred.
34  */
35 static size_t
36 strlcpy(dst, src, siz)
37 	char *dst;
38 	const char *src;
39 	size_t siz;
40 {
41 	char *d = dst;
42 	const char *s = src;
43 	size_t n = siz;
44 
45 	/* Copy as many bytes as will fit */
46 	if (n != 0 && --n != 0) {
47 		do {
48 			if ((*d++ = *s++) == 0)
49 				break;
50 		} while (--n != 0);
51 	}
52 
53 	/* Not enough room in dst, add NUL and traverse rest of src */
54 	if (n == 0) {
55 		if (siz != 0)
56 			*d = '\0';		/* NUL-terminate dst */
57 		while (*s++)
58 			;
59 	}
60 
61 	return(s - src - 1);	/* count does not include NUL */
62 }
63