Shell lockup with on tab completion of tar with --acls option

[Mike Matera]

Bash completion causes the shell to lockup when completing command lines for the TAR command. The following sequence of commands shows the problem:

# starting in an empty directory
mkdir foo
touch foo/bar
touch foo/bak
tar -cvf foo.tar <tab>
tar --acls -cvf foo.tar <tab>

After the last tab the shell is locked up permanently and is no longer usable. This only seems to happen when the --acls option is specified, though it may affect others too (I have only tried --acls).

[Mike Matera (fatboymaximus)]

Digging into /usr/share/bash-completion/completions/tar I found some answers. Basically the completer doesn't understand the intent argument "-c" when the intent is not the first argument. That confused the program and it's trying to extract the index of a (nonexistant) tar file by running:

tar t foo.tar

Lacking the "f" argument TAR is reading from STDIN and that will hang us up forever. I tried CTRL-D but that didn't work.

Attached is a patch that works around the problem by blinding the completer when the first argument is --something. A better solution would be to fix the parser to understand arguments in any position but in the mean time it's better for my mental health not to crash.

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "Workaround patch" seems to be a patch. If it isn't, please remove the "patch" flag from the attachment, remove the "patch" tag, and if you are a member of the ~ubuntu-reviewers, unsubscribe the team.

[This is an automated message performed by a Launchpad user owned by ~brian-murray, for any issues please contact him.]

[Mike Matera (fatboymaximus)]

I had the wrong package selected. This bug affect bash-completion. Sorry.