Hello,

The tarball of hplip 3.18.9 contains several .so files that it installs
as-is:

--8<---------------cut here---------------start------------->8---
ludo@ribbon ~/src/guix$ (cd /tmp; tar xf $(guix build -S hplip))
ludo@ribbon ~/src/guix$ find /tmp/hplip-3.18.9 -name \*.so
/tmp/hplip-3.18.9/prnt/plugins/hbpl1-arm32.so
/tmp/hplip-3.18.9/prnt/plugins/hbpl1-x86_64.so
/tmp/hplip-3.18.9/prnt/plugins/lj-x86_32.so
/tmp/hplip-3.18.9/prnt/plugins/hbpl1-arm64.so
/tmp/hplip-3.18.9/prnt/plugins/hbpl1-x86_32.so
/tmp/hplip-3.18.9/prnt/plugins/lj-arm64.so
/tmp/hplip-3.18.9/prnt/plugins/lj-x86_64.so
/tmp/hplip-3.18.9/prnt/plugins/lj-arm32.so
/tmp/hplip-3.18.9/prnt/hpcups/libImageProcessor-x86_32.so
/tmp/hplip-3.18.9/prnt/hpcups/libImageProcessor-x86_64.so
--8<---------------cut here---------------end--------------->8---

I tried removing them with a snippet (patch attached), but installation
eventually fails while trying to link against libImageProcessor, which
is now missing.

In <https://bugs.launchpad.net/hplip/+bug/1785230/> people suggest that
3.18.6 is the last known-good version.  Indeed that version does not
have the obnoxious libImageProcessor, so that should be fine.  It does
come with the non-free binary plug-ins, though these are just plugins so
removing them will be easier:

--8<---------------cut here---------------start------------->8---
ludo@ribbon ~/src/guix$ find /tmp/hplip-3.18.6/ -name \*.so
/tmp/hplip-3.18.6/prnt/plugins/hbpl1-arm32.so
/tmp/hplip-3.18.6/prnt/plugins/hbpl1-x86_64.so
/tmp/hplip-3.18.6/prnt/plugins/lj-x86_32.so
/tmp/hplip-3.18.6/prnt/plugins/hbpl1-arm64.so
/tmp/hplip-3.18.6/prnt/plugins/hbpl1-x86_32.so
/tmp/hplip-3.18.6/prnt/plugins/lj-arm64.so
/tmp/hplip-3.18.6/prnt/plugins/lj-x86_64.so
/tmp/hplip-3.18.6/prnt/plugins/lj-arm32.so
--8<---------------cut here---------------end--------------->8---

Thus, I propose to:

  1. Revert to 3.18.6 (we’ll upgrade if and when hplip becomes free
     again.)

  2. Add a snippet to remove the non-free plugins.

Thoughts?

Thanks,
Ludo’.