Re: Calibre

[Mark H Weaver <mhw@netris.org>]

Andreas Enge <andreas@enge.fr> writes:
> the attached file adds the e-book management program
> calibre. Eventually, I will put it into ebook.scm. Comments are
> welcome, in particular concerning the xdg issue.

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.

I haven't done a full investigation and don't plan to.  You're adding
this package, so that's your job :)  However, I did verify that your
'license' field is not sufficient, and found the following problems:

(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.

(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 ...".

(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".

We'll need to add a 'snippet' to remove everything that doesn't comply
with the GNU FSDG[*], and to do a more careful job with the 'license'
field..  For now, we could probably assume that removing everything that
Debian removed will be sufficient.

     Thanks,
       Mark

[*] https://gnu.org/distros/free-system-distribution-guidelines.html