1 /*
2  * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND TODD C. MILLER DISCLAIMS ALL
9  * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
10  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL TODD C. MILLER BE LIABLE
11  * FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
13  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
14  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 /*
18  * Copy src to string dst of size siz.  At most siz-1 characters
19  * will be copied.  Always NUL terminates (unless siz == 0).
20  * Returns strlen(src); if retval >= siz, truncation occurred.
21  */
22 #include <string.h>
23 
24 size_t
25 strlcpy(char *dst, const char *src, size_t siz);
26 
27 size_t
strlcpy(char * dst,const char * src,size_t siz)28 strlcpy(char *dst, const char *src, size_t siz)
29 {
30 	char *d = dst;
31 	const char *s = src;
32 	size_t n = siz;
33 
34 	/* Copy as many bytes as will fit */
35 	if (n != 0 && --n != 0) {
36 		do {
37 			if ((*d++ = *s++) == 0)
38 				break;
39 		} while (--n != 0);
40 	}
41 
42 	/* Not enough room in dst, add NUL and traverse rest of src */
43 	if (n == 0) {
44 		if (siz != 0)
45 			*d = '\0';		/* NUL-terminate dst */
46 		while (*s++)
47 			;
48 	}
49 
50 	return(s - src - 1);	/* count does not include NUL */
51 }
52