/*
* 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.
*/
size_t
strlcat( char *dst, const char *src, size_t siz)
{
char *d = dst;
const char *s = src;
size_t n = siz;
size_t 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 */
}
/*
* Copy src to string dst of size siz. At most siz-1 characters
* will be copied. Always NUL terminates (unless siz == 0).
* Returns strlen(src); if retval >= siz, truncation occurred.
*/
size_t
strlcpy( char *dst, const char *src, size_t siz)
{
char *d = dst;
const char *s = src;
size_t n = siz;
/* Copy as many bytes as will fit */
if (n != 0) {
while (--n != 0) {
if ((*d++ = *s++) == ‘\0‘ )
break ;
}
}
/* Not enough room in dst, add NUL and traverse rest of src */
if (n == 0) {
if (siz != 0)
*d = ‘\0‘ ; /* NUL-terminate dst */
while (*s++)
;
}
return (s - src - 1); /* count does not include NUL */
}
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