util_strlcpy.c.svn-base

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#include <string.h>

/* 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.
 */

int strlcpy(char *dst, const char *src, int siz)
{
	register char *d = dst;
	register const char *s = src;
	register int n = siz;

	/* Copy as many bytes as will fit */
	if (n != 0 && --n != 0) {
		do {
			if ((*d++ = *s++) == 0)
				break;
		} while (--n != 0);
	}

	/* 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 */
}

/* 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 == 0).
 * Returns strlen(src); if retval >= siz, truncation occurred.
 */

int strlcat(char *dst, const char *src, int siz)
{
	register char *d = dst;
	register const char *s = src;
	register int n = siz;
	int dlen;

	/* Find the end of dst and adjust bytes left but don't go past end */
	while (*d != '\0' && n-- != 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 */
}