openbsd-compat/basename.c

   1 /*      $OpenBSD: basename.c,v 1.14 2005/08/08 08:05:33 espie Exp $     */
   2
   3 /*
   4  * Copyright (c) 1997, 2004 Todd C. Miller <Todd.Miller@courtesan.com>
   5  *
   6  * Permission to use, copy, modify, and distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18
  19 /* OPENBSD ORIGINAL: lib/libc/gen/basename.c */
  20
  21 #include "includes.h"
  22 #ifndef HAVE_BASENAME
  23 #include <errno.h>
  24 #include <string.h>
  25
  26 char *
  27 basename(const char *path)
  28 {
  29         static char bname[MAXPATHLEN];
  30         size_t len;
  31         const char *endp, *startp;
  32
  33         /* Empty or NULL string gets treated as "." */
  34         if (path == NULL || *path == '\0') {
  35                 bname[0] = '.';
  36                 bname[1] = '\0';
  37                 return (bname);
  38         }
  39
  40         /* Strip any trailing slashes */
  41         endp = path + strlen(path) - 1;
  42         while (endp > path && *endp == '/')
  43                 endp--;
  44
  45         /* All slashes becomes "/" */
  46         if (endp == path && *endp == '/') {
  47                 bname[0] = '/';
  48                 bname[1] = '\0';
  49                 return (bname);
  50         }
  51
  52         /* Find the start of the base */
  53         startp = endp;
  54         while (startp > path && *(startp - 1) != '/')
  55                 startp--;
  56
  57         len = endp - startp + 1;
  58         if (len >= sizeof(bname)) {
  59                 errno = ENAMETOOLONG;
  60                 return (NULL);
  61         }
  62         memcpy(bname, startp, len);
  63         bname[len] = '\0';
  64         return (bname);
  65 }
  66
  67 #endif /* !defined(HAVE_BASENAME) */