[Debian-med-packaging] Bug#908834: Bug#908834: please build zstd udeb so that btrfs-progs can use zstd in Debian Installer

[Alex Mestiashvili]

On 10/09/2018 04:32 PM, Dimitri John Ledkov wrote:
>  is o
> On Tue, 9 Oct 2018 at 12:23, Alex Mestiashvili <amestia at rsh2.donotuse.de> wrote:
>>
>> On 09/14/2018 08:04 PM, Nicholas D Steeves wrote:
>>> Package: zstd
>>> Version: 1.3.5+dfsg-1
>>> Severity: wishlist
>>>
>>> Dear Debian Med Packaging Team,
>>>
>>> Would you please build a zstd udeb so that btrfs-progs can use zstd in
>>> Debian Installer and Rescue System?  It uses zstd for transparent
>>> filesystem compression.
>>>
>>> eg: `chattr +c`, or `btrfs filesystem defrag -c`, or via a mount
>>> option `compress=zstd`.  I believe the first and last of these use the
>>> kernel's libzstd, and that the udeb is primarily required for
>>> `btrfs-repair` to handle zstd extents in the Rescue System.  Also, please continue to CC Dmitri Ledkov, Debian's btrfs-progs maintainer.
>>>
>>> Cheers,
>>> Nicholas
>>>
>>> _______________________________________________
>>> Debian-med-packaging mailing list
>>> Debian-med-packaging at alioth-lists.debian.net
>>> https://alioth-lists.debian.net/cgi-bin/mailman/listinfo/debian-med-packaging
>>>
>>
>>
>> As far as I see it's enough to add udeb stanzas in d/control in order to
>> build the udebs[0].
>> Is there anything else to consider before uploading lisbzstd with udebs?
>>
> 
> No, that's not at all enough. It ends up creating two empty packages,
> without any files in them.

Oh, I see. I thought there is some debhelper magic involved and didn't
check the generated packages..

> 
> One needs to actually install a library into the library udeb and
> tools into tools-udeb.
> Note for fbtrfs only library-udeb is needed.

Does that also apply for btrfs-repair? Initial bug report is about zstd
udeb as I see.

> 
> Maybe https://patches.ubuntu.com/libz/libzstd/libzstd_1.3.5+dfsg-1ubuntu1.patch
> is of help

That's clear now. Thank you.

> 
> Also do get it reviewed, as last time unwritten rules w.r.t. udebs got
> enforced and above patch was rejected on ground of not strict enough
> alternative shlibs deps generated.

Thank you for clarifying, but I didn't understand the reason of reject :).

> 
> Please figure out what's missing before uploading to avoid a reject again.

I've pushed quite the same changes as yours to zstd repository now.

@debian-boot folks, please review and please either fix it or explain
what is required.

Are there any udeb related docs available?

Thank you,
Alex