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tor  0.2.3.18-rc
strlcat.c
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00001 /*     $OpenBSD: strlcat.c,v 1.8 2001/05/13 15:40:15 deraadt Exp $    */
00002 
00003 /*
00004  * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
00005  * All rights reserved.
00006  *
00007  * Redistribution and use in source and binary forms, with or without
00008  * modification, are permitted provided that the following conditions
00009  * are met:
00010  * 1. Redistributions of source code must retain the above copyright
00011  *    notice, this list of conditions and the following disclaimer.
00012  * 2. Redistributions in binary form must reproduce the above copyright
00013  *    notice, this list of conditions and the following disclaimer in the
00014  *    documentation and/or other materials provided with the distribution.
00015  * 3. The name of the author may not be used to endorse or promote products
00016  *    derived from this software without specific prior written permission.
00017  *
00018  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
00019  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
00020  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
00021  * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
00022  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
00023  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
00024  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
00025  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
00026  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
00027  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
00028  */
00029 
00030 #if defined(LIBC_SCCS) && !defined(lint)
00031 static char *rcsid = "$OpenBSD: strlcat.c,v 1.8 2001/05/13 15:40:15 deraadt Exp $";
00032 #endif /* LIBC_SCCS and not lint */
00033 
00034 #include <sys/types.h>
00035 #include <string.h>
00036 
00037 /*
00038  * Appends src to string dst of size siz (unlike strncat, siz is the
00039  * full size of dst, not space left).  At most siz-1 characters
00040  * will be copied.  Always NUL terminates (unless siz <= strlen(dst)).
00041  * Returns strlen(src) + MIN(siz, strlen(initial dst)).
00042  * If retval >= siz, truncation occurred.
00043  */
00044 size_t
00045 strlcat(char *dst, const char *src, size_t siz)
00046 {
00047        register char *d = dst;
00048        register const char *s = src;
00049        register size_t n = siz;
00050        size_t dlen;
00051 
00052        /* Find the end of dst and adjust bytes left but don't go past end */
00053        while (n-- != 0 && *d != '\0')
00054               d++;
00055        dlen = d - dst;
00056        n = siz - dlen;
00057 
00058        if (n == 0)
00059               return(dlen + strlen(s));
00060        while (*s != '\0') {
00061               if (n != 1) {
00062                      *d++ = *s;
00063                      n--;
00064               }
00065               s++;
00066        }
00067        *d = '\0';
00068 
00069        return(dlen + (s - src));   /* count does not include NUL */
00070 }