lib/acl.c

   1 /* acl.c - access control lists
   2
   3    Copyright (C) 2002 Free Software Foundation, Inc.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 2, or (at your option)
   8    any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program; if not, write to the Free Software Foundation,
  17    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18
  19    Written by Paul Eggert.  */
  20
  21 #if HAVE_CONFIG_H
  22 # include <config.h>
  23 #endif
  24
  25 #include <sys/stat.h>
  26 #ifndef S_ISLNK
  27 # define S_ISLNK(Mode) 0
  28 #endif
  29
  30 #include "acl.h"
  31
  32 #include <errno.h>
  33 #ifndef ENOSYS
  34 # define ENOSYS (-1)
  35 #endif
  36
  37 #ifndef MIN_ACL_ENTRIES
  38 # define MIN_ACL_ENTRIES 4
  39 #endif
  40
  41 /* Return 1 if PATH has a nontrivial access control list, 0 if not,
  42    and -1 (setting errno) if an error is encountered.  */
  43
  44 int
  45 file_has_acl (char const *path, struct stat const *pathstat)
  46 {
  47   /* FIXME: This implementation should work on recent-enough versions
  48      of HP-UX, Solaris, and Unixware, but it simply returns 0 with
  49      POSIX 1003.1e (draft 17 -- abandoned), AIX, GNU/Linux, Irix, and
  50      Tru64.  Please see Samba's source/lib/sysacls.c file for
  51      fix-related ideas.  */
  52
  53 #if HAVE_ACL && defined GETACLCNT
  54   if (! S_ISLNK (pathstat->st_mode))
  55     {
  56       int n = acl (path, GETACLCNT, 0, NULL);
  57       return n < 0 ? (errno == ENOSYS ? 0 : -1) : (MIN_ACL_ENTRIES < n);
  58     }
  59 #endif
  60
  61   return 0;
  62 }