Bug#738591: lintian: Add checker for timestamped gzip files

[Jakub Wilk <jwilk@debian.org>]

* Tomasz Buchert <tomasz.buchert@inria.fr>, 2014-02-11, 00:56:
> There is an ongoing project to build reproducible deps (see 
> https://wiki.debian.org/ReproducibleBuilds). One of tasks is to update 
> lintian to emit a tag on gzips that contain timestamps. I've written a 
> simple checker that does exactly that and emits 
> "package-contains-timestamped-gzip". The patch is attached.

We check for a very similar thing already in files.pm (the 
gzip-file-is-not-multi-arch-same-safe tag). Perhaps it would be better 
to reuse that code.

Niels, do you remember why we read timestamp with sysread() and unpack() 
instead of using file_info? I have a vague recollection that we did it 
on purpose, but can't remember the details.

> +Severity: normal

It think it should be at most "wishlist", perhaps even "pedantic".

--
Jakub Wilk