strlcpy.c

/*  $OpenBSD: strlcpy.c,v 1.5 2001/05/13 15:40:16 deraadt Exp $ */

/*
 * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
 * 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.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char *rcsid = "$OpenBSD: strlcpy.c,v 1.5 2001/05/13 15:40:16 deraadt Exp $";
#endif /* LIBC_SCCS and not lint */

#include <string.h>
#include "sectionname.h"

/** \ingroup avr_string
    \fn size_t strlcpy (char *dst, const char *src, size_t siz)
    \brief Copy a string.

    Copy src to string dst of size siz.  At most siz-1 characters will be
    copied.  Always NULL terminates (unless siz == 0).

    \returns The strlcpy() function returns strlen(src). If retval >= siz,
    truncation occurred.  */

ATTRIBUTE_CLIB_SECTION
size_t
strlcpy (char *dst, const char *src, size_t siz)
{
    register char *d = dst;
    register const char *s = src;
    register size_t 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 */
}