Added check for broken alien version

[rincebrain]

Implemented the suggested detection of a broken alien version from #11848

Motivation and Context

Closes #11848 ; does not fix #11650, merely detects the broken version discovered from that.

Description

Added a check for alien 8.95.3, which is known to fail to generate debs 100% of the time, and instead print out a message informing the developer that it's known to be broken and linking them to more information.

How Has This Been Tested?

Tried compiling with alien 8.95 and 8.95.3 installed, verified that it bailed out on the latter and built normally with the former.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Performance enhancement (non-breaking change which improves efficiency)
• Code cleanup (non-breaking change which makes code smaller or more readable)
• Breaking change (fix or feature that would cause existing functionality to change)
• Library ABI change (libzfs, libzfs_core, libnvpair, libuutil and libzfsbootenv)
• Documentation (a change to man pages or other documentation)

Checklist:

• My code follows the OpenZFS code style requirements.
• I have updated the documentation accordingly.
• I have read the contributing document.
• I have added tests to cover my changes.
• I have run the ZFS Test Suite with this change applied.
• All commit messages are properly formatted and contain Signed-off-by.

[behlendorf]

Just to be clear do I understand correctly that only this version of alien is effected? Both older and newer versions work fine? It would be best if we could make sure Debian bullsye ships with a working version, even if we do expect most users to use the distribution provided packages and not alien. @aerusso do you happen to know if getting a newer (or even older) version is still possible? Regardless, adding a warning does seem like the least we can do.

[rincebrain]

Technically, 8.95.2 and 8.95.1 are also affected by at least one of the two bugs, but nobody's shipped those in a released distro that I could find, so I didn't make the check more versatile. It'd be simple enough to do if you'd prefer.

There's not yet any version newer than 8.95.3; one presumes they would ship patches for this in that version, but it's not been cut yet, so who knows.

You have to go out of your way to get 8.95 on bullseye - I think your options are grabbing the buster packages for it or building it yourself. There's not really an easy way to just go "apt install alien-8.95" without some work on your part.

quick edit: the same commit actually caused both bugs, so 8.95.1 and 8.95.2 have both problems as well.

[behlendorf]

Once Debian bullseye is available we'll want to add it to the CI and that looks like it's going to be an issue unless this is resolved in the distribution. Is there either a Debian or alien bug we can reference for this? This might also be a good time to revisit adding some proper deb style packaging in the repository as long it doesn't conflict with the downstream packaging.

[ghost]

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=985835

Awesome, looks like someone is on it as of today.

[behlendorf]

That's good news. It sounds like we'll probably want to include this change either way but it'll be nice if this can get resolved before it's a wide spread issue.