1 /*      $OpenBSD: dirname.c,v 1.7 2002/05/24 21:22:37 deraadt Exp $     */
   2 
   3 /*
   4  * Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com>
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. The name of the author may not be used to endorse or promote products
  16  *    derived from this software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
  19  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
  20  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
  21  * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  22  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  23  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  24  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  25  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  26  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  27  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  */
  29 
  30 #include "includes.h"
  31 #ifndef HAVE_DIRNAME
  32 
  33 #if defined(LIBC_SCCS) && !defined(lint)
  34 static char rcsid[] = "$OpenBSD: dirname.c,v 1.7 2002/05/24 21:22:37 deraadt Exp $";
  35 #endif /* LIBC_SCCS and not lint */
  36 
  37 #include <errno.h>
  38 #include <string.h>
  39 #include <sys/param.h>
  40 
  41 char *
  42 dirname(path)
  43         const char *path;
  44 {
  45         static char bname[MAXPATHLEN];
  46         register const char *endp;
  47 
  48         /* Empty or NULL string gets treated as "." */
  49         if (path == NULL || *path == '\0') {
  50                 (void)strlcpy(bname, ".", sizeof bname);
  51                 return(bname);
  52         }
  53 
  54         /* Strip trailing slashes */
  55         endp = path + strlen(path) - 1;
  56         while (endp > path && *endp == '/')
  57                 endp--;
  58 
  59         /* Find the start of the dir */
  60         while (endp > path && *endp != '/')
  61                 endp--;
  62 
  63         /* Either the dir is "/" or there are no slashes */
  64         if (endp == path) {
  65                 (void)strlcpy(bname, *endp == '/' ? "/" : ".", sizeof bname);
  66                 return(bname);
  67         } else {
  68                 do {
  69                         endp--;
  70                 } while (endp > path && *endp == '/');
  71         }
  72 
  73         if (endp - path + 2 > sizeof(bname)) {
  74                 errno = ENAMETOOLONG;
  75                 return(NULL);
  76         }
  77         strlcpy(bname, path, endp - path + 2);
  78         return(bname);
  79 }
  80 #endif
  81 
  82 #pragma ident   "%Z%%M% %I%     %E% SMI"