bug#17810: 24.3.91; file-acl does not return ACL on Mac OS X

bug#17810: 24.3.91; file-acl does not return ACL on Mac OS X

[YAMAMOTO Mitsuharu]

On Mac OS X >= 10.5, the directory ~/Desktop has ACL, but (file-acl
"~/Desktop") returns nil.

  $ ls -lde ~/Desktop
  drwx------+ 4 mituharu  staff  136  6 11 12:04 /Users/mituharu/Desktop
   0: group:everyone deny delete

A comment in lib/qcopy-acl.c and lib/qset-acl.c says:

  # if !HAVE_ACL_TYPE_EXTENDED
    /* Linux, FreeBSD, IRIX, Tru64 */
...
  # else /* HAVE_ACL_TYPE_EXTENDED */
    /* Mac OS X */

    /* On Mac OS X,  acl_get_file (name, ACL_TYPE_ACCESS)
       and           acl_get_file (name, ACL_TYPE_DEFAULT)
       always return NULL / EINVAL.  You have to use
		     acl_get_file (name, ACL_TYPE_EXTENDED)
       or            acl_get_fd (open (name, ...))
       to retrieve an ACL.
       On the other hand,
		     acl_set_file (name, ACL_TYPE_ACCESS, acl)
       and           acl_set_file (name, ACL_TYPE_DEFAULT, acl)
       have the same effect as
		     acl_set_file (name, ACL_TYPE_EXTENDED, acl):
       Each of these calls sets the file's ACL.  */

So, the following lines in src/fileio.c seems to always result in
returning Qnil.

  acl = acl_get_file (SSDATA (absname), ACL_TYPE_ACCESS);
  if (acl == NULL)
    return Qnil;

If I change the above ACL_TYPE_ACCESS to ACL_TYPE_EXTENDED as an
experiment, then I get the following string as a result of (file-acl
"~/Desktop"):

  "!#acl 1
  group:ABCDEFAB-CDEF-ABCD-EFAB-CDEF0000000C:everyone:12:deny:delete
  "

And I could pass it to set-file-acl to set ACL of another file.

				     YAMAMOTO Mitsuharu
				mituharu@math.s.chiba-u.ac.jp

bug#17810: 24.3.91; file-acl does not return ACL on Mac OS X

[Paul Eggert]

[-- Attachment #1: Type: text/plain, Size: 127 bytes --]

Thanks for the bug report.  Does the attached patch fix things for you? 
  I can't easily test it myself, as I don't use OS X.

[-- Attachment #2: acl.diff --]
[-- Type: text/plain, Size: 593 bytes --]

=== modified file 'src/fileio.c'
--- src/fileio.c	2014-06-08 00:59:05 +0000
+++ src/fileio.c	2014-06-20 06:30:09 +0000
@@ -3013,6 +3013,9 @@
   acl_t acl;
   Lisp_Object acl_string;
   char *str;
+# ifndef HAVE_ACL_TYPE_EXTENDED
+  acl_type_t ACL_TYPE_EXTENDED = ACL_TYPE_ACCESS;
+# endif
 #endif
 
   absname = expand_and_dir_to_file (filename,
@@ -3027,7 +3030,7 @@
 #ifdef HAVE_ACL_SET_FILE
   absname = ENCODE_FILE (absname);
 
-  acl = acl_get_file (SSDATA (absname), ACL_TYPE_ACCESS);
+  acl = acl_get_file (SSDATA (absname), ACL_TYPE_EXTENDED);
   if (acl == NULL)
     return Qnil;
 

bug#17810: 24.3.91; file-acl does not return ACL on Mac OS X

[YAMAMOTO Mitsuharu]

>>>>> On Thu, 19 Jun 2014 23:35:52 -0700, Paul Eggert <eggert@cs.ucla.edu> said:

> Thanks for the bug report.  Does the attached patch fix things for
> you?  I can't easily test it myself, as I don't use OS X.

Yes, it works for me.  Thanks.

				     YAMAMOTO Mitsuharu
				mituharu@math.s.chiba-u.ac.jp

bug#17810: 24.3.91; file-acl does not return ACL on Mac OS X

[Paul Eggert]

OK, I installed that patch as emacs-24 bzr 117271 and am marking this as 
done.