Before 2011 it was recommended to use a prime number for the initial
size. In 2011 the OCaml hash table was reimplemented using a hash
function based on Murmur 3. Hashtbl.create now adjusts the initial
size to the next power of 2 (minimum 16). So replace obsolete
'Hashtbl.create 13' with 'Hashtbl.create 16'.
In filesystems that have many millions of files, the default behaviour
of setfiles is to build a huge hash table containing every filename.
This uses up lots of memory which prevents relabelling from happening
in the reduced memory environment of the libguestfs appliance.
I added the setfiles -A option to change this default behaviour. If
setfiles has the option then use it.
Fixes: https://issues.redhat.com/browse/RHEL-114292
Related: https://issues.redhat.com/browse/RHEL-111165
Related: https://issues.redhat.com/browse/RHEL-111505
The guestfs_selinux_relabel function was very hard to use. In
particular it didn't just do an SELinux relabel as you might expect.
Instead you have to write a whole bunch of code around it (example[1])
to make it useful.
Another problem is that it doesn't let you pass multiple paths to the
setfiles command, but the command itself does permit that (and, as it
turns out, will require it). There is no backwards compatible way to
extend the existing definition to allow a list parameter without
breaking API.
So deprecate guestfs_selinux_relabel. Reimplement it as
guestfs_setfiles. The new function is basically the same as the old
one, but allows you to pass a list of paths. The old function calls
the new function with a single path parameter.
[1] https://github.com/libguestfs/libguestfs-common/blob/master/mlcustomize/SELinux_relabel.ml
