/*      $NetBSD: wcslcat.c,v 1.3 2012/06/25 22:32:46 abs Exp $  */
/*      from OpenBSD: strlcat.c,v 1.3 2000/11/24 11:10:02 itojun Exp    */

/*
* Copyright (c) 1998 Todd C. Miller <[email protected]>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
*    derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
* THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: wcslcat.c,v 1.3 2012/06/25 22:32:46 abs Exp $");
#endif /* LIBC_SCCS and not lint */

#include <sys/types.h>
#include <assert.h>
#include <wchar.h>

/*
* Appends src to string dst of size siz (unlike wcsncat, 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 wcslen(initial dst) + wcslen(src); if retval >= siz,
* truncation occurred.
*/
size_t
wcslcat(wchar_t *dst, const wchar_t *src, size_t siz)
{
       wchar_t *d = dst;
       const wchar_t *s = src;
       size_t n = siz;
       size_t dlen;

       _DIAGASSERT(dst != NULL);
       _DIAGASSERT(src != NULL);

       /* 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 + wcslen(s));
       while (*s != '\0') {
               if (n != 1) {
                       *d++ = *s;
                       n--;
               }
               s++;
       }
       *d = '\0';

       return(dlen + (s - src));       /* count does not include NUL */
}