volname does not work for dvd's / udf images

[Dan Kegel]

Binary package hint: eject

The package 'eject' includes the handy utility 'volname'.
eject works with both cd-roms and dvds, but volname doesn't.
Let's fix that. I had a quick look at what it would take.

First, udf seems complex, so rather than extend the simple
hardcoded iso parser in volname.c, it might make sense to
use libdvdread's handy UDFGetVolumeIdentifier() function,
and fall back to the existing iso parser if that fails (e.g. if the disc
is not udf format).

Second, volname currently right-justifies the volume name,
which probably works nicely with isos because their names
are space-padded, but looks funny with dvds, because
UDFGetVolumeIdentifier does not space-pad. Might want
to left-justify the output of volname, or remove the padding.

Third, libdvdread suffers from a bug
( http://bugzilla.mplayerhq.hu/show_bug.cgi?id=1451 )
which keeps it from reading the volume name properly.
This is fixed upstream, but they haven't don't a release
yet, so we'd want to include a patch.

Fourth, libdvd's DVDOpen() function prints an annoying
warning about encrypted dvds not being supported, even
when you're just getting a volume name. That probably should
be suppressed or printed later, so it's not seen when just
retrieving the volume name.

I'll attach my quickie patches to the eject and libdvdread packages
showing what I have so far. Ideally, someone will reply
and say "Oh, we already fixed all that" :-)

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: eject 2.1.5+deb1+cvs20081104-7
ProcVersionSignature: Ubuntu 2.6.32-25.45-generic 2.6.32.21+drm33.7
Uname: Linux 2.6.32-25-generic i686
NonfreeKernelModules: nvidia
Architecture: i386
Date: Sun Nov 21 23:59:49 2010
InstallationMedia: Ubuntu 9.10 "Karmic Koala" - Release i386 (20091028.5)
ProcEnviron:
 LANG=en_US.utf8
 SHELL=/bin/bash
SourcePackage: eject

[Scott Ritchie (scottritchie)]

I can confirm the patch fixes the problem, although I'll note that this will pull libdvdread into the default install if done.

[Dan Kegel (dank)]

libudf is another possible alternative to libdvdread. I need to educate myself a bit about these...

[Evan Broder (broder)]

I think a patch that uses libudf would be better, since libudf is already in main and libdvdread is not - you wouldn't need to go through the MIR process.

libudf, though in main, also isn't in the default desktop install currently, but that's not really a big issue, as it's miniscule.

Dan, can you try to come up with a patch that uses libudf? I'm going to unsubscribe ubuntu-sponsors while you work on that, but feel free to resubscribe when you have a new patch ready.

Thanks for working on this.

[Dan Kegel (dank)]

Actually, given the spirit of the current volname.c, perhaps
we should write the simplest possible volume name getting
code. It turns out to be not too hard to write. Attached
is a prototype written in shell (I need to deploy something
before this bug is fixed). I'll translate it to C and resubmit a patch.

[Gianfranco Costamagna (costamagnagianfranco)]

Hi Dan, do you have any news on this?

[Dan Kegel (dank)]

No, I guess I got distracted. I'm pretty busy; if someone else wants to pick this up, that'd be fine.

[Gianfranco Costamagna (costamagnagianfranco)]

Hi Dan, unfortunately I'm not too much involved in eject code, and volname is not a tool that I use currently... I don't know if I can help so much