[Libguestfs] [RFC PATCH v1 3/3] daemon: list-filesystems: Don't list partitioned md devices

[Richard W.M. Jones]

On Tue, Jan 23, 2018 at 12:38:24PM +0200, Nikolay Ivanets wrote:
> 2018-01-23 12:16 GMT+02:00 Richard W.M. Jones <rjones at redhat.com>:
> > On Tue, Jan 23, 2018 at 12:44:13AM +0200, Mykola Ivanets wrote:
> >> Filter partitioned md devices out the same way as partitioned physical devices are filtered out
> >> ---
> >>  daemon/listfs.ml | 22 +++++++++-------------
> >>  1 file changed, 9 insertions(+), 13 deletions(-)
> >>
> >> diff --git a/daemon/listfs.ml b/daemon/listfs.ml
> >> index 370ffb4..dc424f5 100644
> >> --- a/daemon/listfs.ml
> >> +++ b/daemon/listfs.ml
> >> @@ -24,24 +24,20 @@ let rec list_filesystems () =
> >>    let has_lvm2 = Lvm.available () in
> >>    let has_ldm = Ldm.available () in
> >>
> >> -  let devices = Devsparts.list_devices () in
> >>    let partitions = Devsparts.list_partitions () in
> >> -  let mds = Md.list_md_devices () in
> >>
> >>    (* Look to see if any devices directly contain filesystems
> >> -   * (RHBZ#590167).  However vfs-type will fail to tell us anything
> >> +   * (RHBZ#590167). However vfs-type will fail to tell us anything
> >
> > This whitespace change is wrong.
> 
> Ah, I didn't realize double-whitespace is used intentionally.
> Seems sentences should be separated with double-whitespace?
> What is the reason (just curious)?

It's part of the GNU coding standards that we (broadly) follow:

https://www.gnu.org/prep/standards/standards.html#Comments

More generally:

https://en.wikipedia.org/wiki/Sentence_spacing

Rich.

> >>     * useful about devices which just contain partitions, so we also
> >> -   * get the list of partitions and exclude the corresponding devices
> >> -   * by using part-to-dev.
> >> +   * get the list of partitions and exclude the corresponding devices.
> >>     *)
> >> -  let devices_containing_partitions = List.fold_left (
> >> -    fun set part ->
> >> -      StringSet.add (Devsparts.part_to_dev part) set
> >> -  ) StringSet.empty partitions in
> >> -  let devices = List.filter (
> >> -    fun dev ->
> >> -      not (StringSet.mem dev devices_containing_partitions)
> >> -  ) devices in
> >> +  let device_without_partitions device =
> >> +    not (Devsparts.is_partitioned_device device) in
> >> +
> >> +  let devices = Devsparts.list_devices () in
> >> +  let devices = List.filter device_without_partitions devices in
> >> +  let mds = Md.list_md_devices () in
> >> +  let mds = List.filter device_without_partitions mds in
> >
> > Yes, this is better than the previous approach with sets.
> >
> > Rich.
> >
> > --
> > Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
> > Read my programming and virtualization blog: http://rwmj.wordpress.com
> > Fedora Windows cross-compiler. Compile Windows programs, test, and
> > build Windows installers. Over 100 libraries supported.
> > http://fedoraproject.org/wiki/MinGW
> 
> --
>     Nikolay Ivanets

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
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