xref: /optee_os/lib/libutils/ext/strlcpy.c (revision bc420748bfc44a9e09000a3966fc59e9e0219df4)
1 /* This file is copied from newlib-1.19 */
2 
3 /*      $OpenBSD: strlcpy.c,v 1.5 2001/05/13 15:40:16 deraadt Exp $        */
4 
5 /*
6  * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. The name of the author may not be used to endorse or promote products
18  *    derived from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
21  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
22  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
23  * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
24  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
25  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
26  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
27  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
28  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
29  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #if defined(LIBC_SCCS) && !defined(lint)
33 static char *rcsid =
34 	"$OpenBSD: strlcpy.c,v 1.5 2001/05/13 15:40:16 deraadt Exp $";
35 #endif /* LIBC_SCCS and not lint */
36 
37 #include <types_ext.h>
38 #include <string_ext.h>
39 
40 /*
41  * Copy src to string dst of size siz.  At most siz-1 characters
42  * will be copied.  Always NUL terminates (unless siz == 0).
43  * Returns strlen(src); if retval >= siz, truncation occurred.
44  */
45 size_t strlcpy(char *dst, const char *src, size_t siz)
46 {
47 	register char *d = dst;
48 	register const char *s = src;
49 	register size_t n = siz;
50 
51 	/* Copy as many bytes as will fit */
52 	if (n != 0 && --n != 0) {
53 		do {
54 			if ((*d++ = *s++) == 0)
55 				break;
56 		} while (--n != 0);
57 	}
58 
59 	/* Not enough room in dst, add NUL and traverse rest of src */
60 	if (n == 0) {
61 		if (siz != 0)
62 			*d = '\0';	/* NUL-terminate dst */
63 		while (*s++)
64 			;
65 	}
66 
67 	return s - src - 1;	/* count does not include NUL */
68 }
69