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      1 /*	$NetBSD: strlcpy.c,v 1.2 2009/06/30 02:44:52 agc 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 "compat.h"
     21 
     22 #include <sys/types.h>
     23 #include <assert.h>
     24 #include <string.h>
     25 
     26 
     27 #if !HAVE_STRLCPY
     28 /*
     29  * Copy src to string dst of size siz.  At most siz-1 characters
     30  * will be copied.  Always NUL terminates (unless siz == 0).
     31  * Returns strlen(src); if retval >= siz, truncation occurred.
     32  */
     33 size_t
     34 #ifdef _LIBC
     35 _strlcpy(dst, src, siz)
     36 #else
     37 strlcpy(dst, src, siz)
     38 #endif
     39 	char *dst;
     40 	const char *src;
     41 	size_t siz;
     42 {
     43 	char *d = dst;
     44 	const char *s = src;
     45 	size_t n = siz;
     46 
     47 	_DIAGASSERT(dst != NULL);
     48 	_DIAGASSERT(src != NULL);
     49 
     50 	/* Copy as many bytes as will fit */
     51 	if (n != 0 && --n != 0) {
     52 		do {
     53 			if ((*d++ = *s++) == 0)
     54 				break;
     55 		} while (--n != 0);
     56 	}
     57 
     58 	/* Not enough room in dst, add NUL and traverse rest of src */
     59 	if (n == 0) {
     60 		if (siz != 0)
     61 			*d = '\0';		/* NUL-terminate dst */
     62 		while (*s++)
     63 			;
     64 	}
     65 
     66 	return(s - src - 1);	/* count does not include NUL */
     67 }
     68 #endif
     69