gen/FreeBSD/dirname.c

   1 /*      $OpenBSD: dirname.c,v 1.13 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 #include <sys/cdefs.h>
  20 __FBSDID("$FreeBSD: src/lib/libc/gen/dirname.c,v 1.8 2008/11/03 05:19:45 delphij Exp $");
  21
  22 #include <errno.h>
  23 #include <libgen.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <sys/param.h>
  27
  28 char *
  29 dirname_r(const char *path, char *dname)
  30 {
  31         const char *endp;
  32         size_t len;
  33
  34         /* Empty or NULL string gets treated as "." */
  35         if (path == NULL || *path == '\0') {
  36                 dname[0] = '.';
  37                 dname[1] = '\0';
  38                 return (dname);
  39         }
  40
  41         /* Strip any trailing slashes */
  42         endp = path + strlen(path) - 1;
  43         while (endp > path && *endp == '/')
  44                 endp--;
  45
  46         /* Find the start of the dir */
  47         while (endp > path && *endp != '/')
  48                 endp--;
  49
  50         /* Either the dir is "/" or there are no slashes */
  51         if (endp == path) {
  52                 dname[0] = *endp == '/' ? '/' : '.';
  53                 dname[1] = '\0';
  54                 return (dname);
  55         } else {
  56                 /* Move forward past the separating slashes */
  57                 do {
  58                         endp--;
  59                 } while (endp > path && *endp == '/');
  60         }
  61
  62         len = endp - path + 1;
  63         if (len >= MAXPATHLEN) {
  64                 errno = ENAMETOOLONG;
  65                 return (NULL);
  66         }
  67         memmove(dname, path, len);
  68         dname[len] = '\0';
  69         return (dname);
  70 }
  71
  72 #if __DARWIN_UNIX03
  73 #define const /**/
  74 #endif
  75
  76 char *
  77 dirname(const char *path)
  78 {
  79         static char *dname = NULL;
  80
  81         if (dname == NULL) {
  82                 dname = (char *)malloc(MAXPATHLEN);
  83                 if (dname == NULL)
  84                         return (NULL);
  85         }
  86         return (dirname_r(path, dname));
  87 }