acl: finish Cygwin support

[Bruno Haible]

On Cygwin, two files with the same ACL can have different mode:
$ ls -l tmpfile1 
-rwxr-x--- 1 haible None 14 Jun  2 22:06 tmpfile1
$ getfacl.exe tmpfile1
# file: tmpfile1
# owner: haible
# group: None
user::rw-
group::r-x
mask:rwx
other:---
$ echo foo > tmpfile2
$ chmod 650 tmpfile2
$ getfacl.exe tmpfile2 
# file: tmpfile2
# owner: haible
# group: None
user::rw-
group::r-x
mask:rwx
other:---
$ ls -l tmpfile1 tmpfile2 
-rwxr-x--- 1 haible None 14 Jun  2 22:06 tmpfile1
-rw-r-x--- 1 haible None  4 Jun  2 22:08 tmpfile2

Therefore, on Cygwin, unlike on Solaris, after an ACL has been set, the
'chmod' call must be performed, even if the mode is a subset of 0777.


2008-06-08  Bruno Haible  <address@hidden>

        Add support for Cygwin ACLs.
        * lib/acl-internal.h (MODE_INSIDE_ACL): New macro for Solaris-like API.
        * lib/set-mode-acl.c (qset_acl) [!MODE_INSIDE_ACL]: Don't optimize away
        the chmod_or_fchmod call.
        * lib/copy-acl.c (qcopy_acl) [!MODE_INSIDE_ACL]: Likewise.

*** lib/acl-internal.h.orig     2008-06-08 16:49:30.000000000 +0200
--- lib/acl-internal.h  2008-06-08 16:44:43.000000000 +0200
***************
*** 160,165 ****
--- 160,173 ----
  
  # elif HAVE_ACL && defined GETACL /* Solaris, Cygwin, not HP-UX */
  
+ /* Set to 1 if a file's mode is implicit by the ACL.
+    Set to 0 if a file's mode is stored independently from the ACL.  */
+ #  if defined __CYGWIN__ /* Cygwin */
+ #   define MODE_INSIDE_ACL 0
+ #  else /* Solaris */
+ #   define MODE_INSIDE_ACL 1
+ #  endif
+ 
  /* Return 1 if the given ACL is non-trivial.
     Return 0 if it is trivial, i.e. equivalent to a simple stat() mode.  */
  extern int acl_nontrivial (int count, aclent_t *entries);
*** lib/copy-acl.c.orig 2008-06-08 16:49:30.000000000 +0200
--- lib/copy-acl.c      2008-06-08 16:49:17.000000000 +0200
***************
*** 330,337 ****
      if (count == 0)
        return qset_acl (dst_name, dest_desc, mode);
  
!   did_chmod = 0; /* set to 1 once the mode bits in 0777 have been set,
!                   set to 2 once the mode bits other than 0777 have been set */
    saved_errno = 0; /* the first non-ignorable error code */
  
    /* If both ace_entries and entries are available, try SETACL before
--- 330,336 ----
      if (count == 0)
        return qset_acl (dst_name, dest_desc, mode);
  
!   did_chmod = 0; /* set to 1 once the mode bits in 0777 have been set */
    saved_errno = 0; /* the first non-ignorable error code */
  
    /* If both ace_entries and entries are available, try SETACL before
***************
*** 371,377 ****
    free (ace_entries);
  #  endif
  
!   if (did_chmod <= ((mode & (S_ISUID | S_ISGID | S_ISVTX)) ? 1 : 0))
      {
        /* We did not call chmod so far, and either the mode and the ACL are
         separate or special bits are to be set which don't fit into ACLs.  */
--- 370,377 ----
    free (ace_entries);
  #  endif
  
!   if (!MODE_INSIDE_ACL
!       || did_chmod <= ((mode & (S_ISUID | S_ISGID | S_ISVTX)) ? 1 : 0))
      {
        /* We did not call chmod so far, and either the mode and the ACL are
         separate or special bits are to be set which don't fit into ACLs.  */
*** lib/set-mode-acl.c.orig     2008-06-08 16:49:30.000000000 +0200
--- lib/set-mode-acl.c  2008-06-08 16:45:52.000000000 +0200
***************
*** 305,311 ****
        }
    }
    
!   if (mode & (S_ISUID | S_ISGID | S_ISVTX))
      {
        /* We did not call chmod so far, so the special bits have not yet
           been set.  */
--- 305,311 ----
        }
    }
    
!   if (!MODE_INSIDE_ACL || (mode & (S_ISUID | S_ISGID | S_ISVTX)))
      {
        /* We did not call chmod so far, so the special bits have not yet
           been set.  */