Line data    Source code

       1              : /*
       2              :  * src/port/strlcat.c
       3              :  *
       4              :  *  $OpenBSD: strlcat.c,v 1.13 2005/08/08 08:05:37 espie Exp $  */
       5              : 
       6              : /*
       7              :  * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
       8              :  *
       9              :  * Permission to use, copy, modify, and distribute this software for any
      10              :  * purpose with or without fee is hereby granted, provided that the above
      11              :  * copyright notice and this permission notice appear in all copies.
      12              :  *
      13              :  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
      14              :  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
      15              :  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
      16              :  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
      17              :  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
      18              :  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
      19              :  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
      20              :  */
      21              : 
      22              : #include "c.h"
      23              : 
      24              : 
      25              : /*
      26              :  * Appends src to string dst of size siz (unlike strncat, siz is the
      27              :  * full size of dst, not space left).  At most siz-1 characters
      28              :  * will be copied.  Always NUL terminates (unless siz <= strlen(dst)).
      29              :  * Returns strlen(src) + MIN(siz, strlen(initial dst)).
      30              :  * If retval >= siz, truncation occurred.
      31              :  */
      32              : size_t
      33              : strlcat(char *dst, const char *src, size_t siz)
      34              : {
      35         1097 :     char       *d = dst;
      36         1097 :     const char *s = src;
      37         1097 :     size_t      n = siz;
      38              :     size_t      dlen;
      39              : 
      40              :     /* Find the end of dst and adjust bytes left but don't go past end */
      41        62691 :     while (n-- != 0 && *d != '\0')
      42        61594 :         d++;
      43         1097 :     dlen = d - dst;
      44         1097 :     n = siz - dlen;
      45              : 
      46         1097 :     if (n == 0)
      47            0 :         return (dlen + strlen(s));
      48        15720 :     while (*s != '\0')
      49              :     {
      50        14623 :         if (n != 1)
      51              :         {
      52        14623 :             *d++ = *s;
      53        14623 :             n--;
      54              :         }
      55        14623 :         s++;
      56              :     }
      57         1097 :     *d = '\0';
      58              : 
      59         1097 :     return (dlen + (s - src));  /* count does not include NUL */
      60              : }