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      1 /*	$NetBSD: strlcpy.c,v 1.4 2024/11/01 21:11:37 riastradh 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 #if !defined(_KERNEL) && !defined(_STANDALONE)
     21 #if HAVE_NBTOOL_CONFIG_H
     22 #include "nbtool_config.h"
     23 #endif
     24 
     25 #include <sys/cdefs.h>
     26 #if defined(LIBC_SCCS) && !defined(lint)
     27 __RCSID("$NetBSD: strlcpy.c,v 1.4 2024/11/01 21:11:37 riastradh Exp $");
     28 #endif /* LIBC_SCCS and not lint */
     29 
     30 #ifdef _LIBC
     31 #include "namespace.h"
     32 #endif
     33 #include <sys/types.h>
     34 #include <assert.h>
     35 #include <string.h>
     36 
     37 #ifdef _LIBC
     38 # ifdef __weak_alias
     39 __weak_alias(strlcpy, _strlcpy)
     40 # endif
     41 #endif
     42 #else
     43 #include <lib/libkern/libkern.h>
     44 #endif /* !_KERNEL && !_STANDALONE */
     45 
     46 
     47 #if !HAVE_STRLCPY
     48 /*
     49  * Copy src to string dst of size siz.  At most siz-1 characters
     50  * will be copied.  Always NUL terminates (unless siz == 0).
     51  * Returns strlen(src); if retval >= siz, truncation occurred.
     52  */
     53 size_t
     54 strlcpy(char *__restrict dst, const char *__restrict src, size_t siz)
     55 {
     56 	char *d = dst;
     57 	const char *s = src;
     58 	size_t n = siz;
     59 
     60 	_DIAGASSERT(dst != NULL);
     61 	_DIAGASSERT(src != NULL);
     62 
     63 	/* Copy as many bytes as will fit */
     64 	if (n != 0 && --n != 0) {
     65 		do {
     66 			if ((*d++ = *s++) == 0)
     67 				break;
     68 		} while (--n != 0);
     69 	}
     70 
     71 	/* Not enough room in dst, add NUL and traverse rest of src */
     72 	if (n == 0) {
     73 		if (siz != 0)
     74 			*d = '\0';		/* NUL-terminate dst */
     75 		while (*s++)
     76 			;
     77 	}
     78 
     79 	return(s - src - 1);	/* count does not include NUL */
     80 }
     81 #endif
     82