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      1 /*	$NetBSD: strlcpy.c,v 1.3 2007/06/04 18:19:27 christos Exp $	*/
      2 /*	$OpenBSD: strlcpy.c,v 1.7 2003/04/12 21:56:39 millert Exp $	*/
      3 
      4 /*
      5  * Copyright (c) 1998 Todd C. Miller <Todd.Miller (at) courtesan.com>
      6  *
      7  * Permission to use, copy, modify, and distribute this software for any
      8  * purpose with or without fee is hereby granted, provided that the above
      9  * copyright notice and this permission notice appear in all copies.
     10  *
     11  * THE SOFTWARE IS PROVIDED "AS IS" AND TODD C. MILLER DISCLAIMS ALL
     12  * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
     13  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL TODD C. MILLER BE LIABLE
     14  * FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
     15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
     16  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
     17  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
     18  */
     19 
     20 #include "config.h"
     21 
     22 #if defined(LIBC_SCCS) && !defined(lint)
     23 __RCSID("$NetBSD: strlcpy.c,v 1.3 2007/06/04 18:19:27 christos Exp $");
     24 #endif /* LIBC_SCCS and not lint */
     25 
     26 #include <sys/types.h>
     27 #include <assert.h>
     28 #include <string.h>
     29 
     30 #ifdef _LIBC
     31 # ifdef __weak_alias
     32 __weak_alias(strlcpy, _strlcpy)
     33 # endif
     34 #endif
     35 
     36 #if !HAVE_STRLCPY
     37 /*
     38  * Copy src to string dst of size siz.  At most siz-1 characters
     39  * will be copied.  Always NUL terminates (unless siz == 0).
     40  * Returns strlen(src); if retval >= siz, truncation occurred.
     41  */
     42 size_t
     43 strlcpy(char *dst, const char *src, size_t siz)
     44 {
     45 	char *d = dst;
     46 	const char *s = src;
     47 	size_t n = siz;
     48 
     49 	_DIAGASSERT(dst != NULL);
     50 	_DIAGASSERT(src != NULL);
     51 
     52 	/* Copy as many bytes as will fit */
     53 	if (n != 0 && --n != 0) {
     54 		do {
     55 			if ((*d++ = *s++) == 0)
     56 				break;
     57 		} while (--n != 0);
     58 	}
     59 
     60 	/* Not enough room in dst, add NUL and traverse rest of src */
     61 	if (n == 0) {
     62 		if (siz != 0)
     63 			*d = '\0';		/* NUL-terminate dst */
     64 		while (*s++)
     65 			;
     66 	}
     67 
     68 	return(s - src - 1);	/* count does not include NUL */
     69 }
     70 #endif
     71