Re: Calibre

[Andreas Enge <andreas@enge.fr>]

On Tue, Feb 17, 2015 at 12:02:00AM -0500, Mark H Weaver wrote:
> The calibre source tarball contains non-free software.  Debian
> distributes their own excerpted source tarball instead, with the
> src/unrar, src/calibre/ebooks/markdown, and resources/viewer/mathjax
> directories removed, as well as src/odf/thumbnail.py.

Amazing, thanks for looking into it. How do you find out which files
debian drops? I suppose that a "dfsg" in the package name is a warning
sign? This is even more surprising as there is the file COPYRIGHT
in the distribution, which diligently lists the licenses of lots of
packages, except apparently for the non-free ones... I will try
to contact the upstream author.

> (1) src/unrar's license includes the following clause:
> 
> --8<---------------cut here---------------start------------->8---
>    2. UnRAR source code may be used in any software to handle
>       RAR archives without limitations free of charge, but cannot be
>       used to develop RAR (WinRAR) compatible archiver and to
>       re-create RAR compression algorithm, which is proprietary.
>       Distribution of modified UnRAR source code in separate form
>       or as a part of other software is permitted, provided that
>       full text of this paragraph, starting from "UnRAR source code"
>       words, is included in license, or in documentation if license
>       is not available, and in source code comments of resulting package.
> --8<---------------cut here---------------end--------------->8---
> 
>     This restriction on use makes it non-free software.

Clearly so!

> (2) src/calibre/ebooks/markdown/serializers.py license includes the text:
> 
> --8<---------------cut here---------------start------------->8---
>   # By obtaining, using, and/or copying this software and/or its
>   # associated documentation, you agree that you have read, understood,
>   # and will comply with the following terms and conditions:
>   #
>   # Permission to use, copy, modify, and distribute this software and
>   # its associated documentation for any purpose and without fee is
>   # hereby granted, provided that the above copyright notice appears in
>   # all copies, and that both that copyright notice and this permission
>   # notice appear in supporting documentation, and that the name of
>   # Secret Labs AB or the author not be used in advertising or publicity
>   # pertaining to distribution of the software without specific, written
>   # prior permission.
> --8<---------------cut here---------------end--------------->8---
> 
>     I'm not as confident that this one is a problem, partly because I
>     guess it is probably unenforceable, but the first paragraph is
>     attempting to put a restriction on use.  They are saying that you're
>     not even allowed to use this software unless you have "read,
>     understood, and will comply with ...".

I suppose that the first sentence merely states "the following license
is valid", so I do not think it is a real problem. One always needs to
comply with the license, no?

> (3) src/odf/thumbnail.py simply says "License: Freeware".  I have no
>     idea what that means.  It is "Non-functional Data" (an image), so
>     (quoting the GNU FSDG) "It can be included in a free system
>     distribution as long as its license gives you permission to copy and
>     redistribute, both for commercial and non-commercial purposes."
>     However, I don't think we can deduce that from "License: Freeware".

I think it is supposed to mean "public domain", but that is just guessing.
We should drop the file.

I will try to take out 1) and 3); I am not sure about 2), though.
As usual in python, I suppose that things will still compile and install,
and then one just needs to hope that it still works.

Andreas