wmii/libcext/strlcat.c

56 lines
1.7 KiB
C

/*
* Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/types.h>
#include <string.h>
#include "cext.h"
/*
* Appends src to string dst of size siz (unlike strncat, siz is the
* full size of dst, not space left). At most siz-1 characters
* will be copied. Always NUL terminates (unless siz <= strlen(dst)).
* Returns strlen(src) + MIN(siz, strlen(initial dst)).
* If retval >= siz, truncation occurred.
*/
unsigned int
cext_strlcat(char *dst, const char *src, unsigned int siz)
{
register char *d = dst;
register const char *s = src;
register unsigned int n = siz;
unsigned int dlen;
/* Find the end of dst and adjust bytes left but don't go past end */
while(n-- != 0 && *d != 0)
d++;
dlen = d - dst;
n = siz - dlen;
if(n == 0)
return (dlen + strlen(s));
while(*s != 0) {
if(n != 1) {
*d++ = *s;
n--;
}
s++;
}
*d = 0;
return (dlen + (s - src)); /* count does not include NUL */
}