1  /*
       2    File: acl_get_file.c
       3  
       4    Copyright (C) 1999, 2000
       5    Andreas Gruenbacher, <andreas.gruenbacher@gmail.com>
       6  
       7    This program is free software; you can redistribute it and/or
       8    modify it under the terms of the GNU Lesser General Public
       9    License as published by the Free Software Foundation; either
      10    version 2.1 of the License, or (at your option) any later version.
      11  
      12    This program is distributed in the hope that it will be useful,
      13    but WITHOUT ANY WARRANTY; without even the implied warranty of
      14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      15    Lesser General Public License for more details.
      16  
      17    You should have received a copy of the GNU Lesser General Public
      18    License along with this library; if not, write to the Free Software
      19    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
      20  */
      21  
      22  #include "config.h"
      23  #include <sys/types.h>
      24  #include <sys/stat.h>
      25  #include <unistd.h>
      26  #include <stdio.h>
      27  #include <sys/xattr.h>
      28  #include "libacl.h"
      29  #include "__acl_from_xattr.h"
      30  
      31  #include "byteorder.h"
      32  #include "acl_ea.h"
      33  
      34  /* 23.4.16 */
      35  acl_t
      36  acl_get_file(const char *path_p, acl_type_t type)
      37  {
      38  	const size_t size_guess = acl_ea_size(16);
      39  	char *ext_acl_p = alloca(size_guess);
      40  	const char *name;
      41  	int retval;
      42  
      43  	switch(type) {
      44  		case ACL_TYPE_ACCESS:
      45  			name = ACL_EA_ACCESS;
      46  			break;
      47  		case ACL_TYPE_DEFAULT:
      48  			name = ACL_EA_DEFAULT;
      49  			break;
      50  		default:
      51  			errno = EINVAL;
      52  			return NULL;
      53  	}
      54  
      55  	if (!ext_acl_p)
      56  		return NULL;
      57  	retval = getxattr(path_p, name, ext_acl_p, size_guess);
      58  	if (retval == -1 && errno == ERANGE) {
      59  		retval = getxattr(path_p, name, NULL, 0);
      60  		if (retval > 0) {
      61  			ext_acl_p = alloca(retval);
      62  			if (!ext_acl_p)
      63  				return NULL;
      64  			retval = getxattr(path_p, name, ext_acl_p, retval);
      65  		}
      66  	}
      67  	if (retval > 0) {
      68  		acl_t acl = __acl_from_xattr(ext_acl_p, retval);
      69  		return acl;
      70  	} else if (retval == 0 || errno == ENOATTR || errno == ENODATA) {
      71  		struct stat st;
      72  
      73  		if (stat(path_p, &st) != 0)
      74  			return NULL;
      75  
      76  		if (type == ACL_TYPE_DEFAULT) {
      77  			if (S_ISDIR(st.st_mode))
      78  				return acl_init(0);
      79  			else {
      80  				errno = EACCES;
      81  				return NULL;
      82  			}
      83  		} else
      84  			return acl_from_mode(st.st_mode);
      85  	} else
      86  		return NULL;
      87  }
      88