Bug#763338: /usr/bin/vorbistagedit: Doesn't escape filenames properly

[Martin Steghöfer]

Thank you for reporting this problem, Roland!

I tried to track the problem down. I'm certainly not a shell-script 
expert, but I think I fixed it.

The patch that was applied earlier to fix this bug only fixed the 
quoting of the *input* to "getopt". However, there was still a problem 
with the interpretation of its *output* that didn't take into account 
its quoting. "GNU getopt" quotes its output, so it can be correctly 
split into parameters. However, just using that output directly in a for 
loop doesn't take into account that quoting, but splits the output 
string at every space regardless its quoting.

To avoid this, the output of "getopt" is now parsed using "eval set --", 
which overwrites the original command-line parameters with the ones 
provided by "getopt", taking into account quoting.

Iterating over those parameters using a "while" loop with the "shift" 
command (to advance) provides an additional positive effect: The 
possibility to process the options in the first loop and the filenames 
in a second loop. Before, the filename loop processed all options a 
second time. Therefore you could only have options that exited 
immediately (otherwise they would be interpreted as filenames in the 
second loop).

The changes are in git's master branch right now. We should probably 
cherry-pick the commit into the branch "jessie-fixes" and upload a new 
version of the package because this has a realistic chance of going into 
jessie, doesn't it?

Could somebody maybe give it a little more testing? I'm not sure, if my 
own testing covered all possible edge cases.

Cheers,
Martin