Otherwise, things like hp-setup segfault if you run them from another
nixpkgs checkout:
```
HP Linux Imaging and Printing System (ver. 3.20.5)
Printer/Fax Setup Utility ver. 9.0
Copyright (c) 2001-18 HP Development Company, LP
This software comes with ABSOLUTELY NO WARRANTY.
This is free software, and you are welcome to distribute it
under certain conditions. See COPYING file for more details.
qt.qpa.plugin: Could not find the Qt platform plugin "xcb" in ""
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.
[1] 4543 abort (core dumped) result/bin/hp-setup
```
Otherwise, things like `hp-setup` fail finding gi:
```
HP Linux Imaging and Printing System (ver. 3.20.5)
Printer/Fax Setup Utility ver. 9.0
Copyright (c) 2001-18 HP Development Company, LP
This software comes with ABSOLUTELY NO WARRANTY.
This is free software, and you are welcome to distribute it
under certain conditions. See COPYING file for more details.
Traceback (most recent call last):
File "/nix/store/rmzq8c4n47s4q4p31w18waz0zrba2ljl-hplip-3.20.5/share/hplip/setup.py", line 314, in <module>
ui = import_module(ui_package + ".setupdialog")
File "/nix/store/n0b076p351ma864q38if4yglsg99hw2s-python3-3.8.3/lib/python3.8/importlib/__init__.py", line 127, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 1014, in _gcd_import
File "<frozen importlib._bootstrap>", line 991, in _find_and_load
File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 671, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 783, in exec_module
File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
File "/nix/store/rmzq8c4n47s4q4p31w18waz0zrba2ljl-hplip-3.20.5/share/hplip/ui5/setupdialog.py", line 31, in <module>
from base import device, utils, models, pkit
File "/nix/store/rmzq8c4n47s4q4p31w18waz0zrba2ljl-hplip-3.20.5/share/hplip/base/pkit.py", line 38, in <module>
from gi import _gobject as gobject
ModuleNotFoundError: No module named 'gi'
```
This plugin adds support for the GT-S650, Perfection V19 and
Perfection V39 scanners. I've tested it personally with an Epson
Perfection V39.
This plugin uses the ISCAN_FIRMWARE_DIR environment variable, not
ISCAN_FW_DIR. A quick grep didn't find any use of ISCAN_FW_DIR in the
currently packaged plugins, but a quick Google suggests that this
variable does (or at least used to) exist, so I'm not touching it.
Building with -std=c99 breaks the obsolete "%as" format string, which
completely breaks the parsing of epkowa interpreters. This means that
no scanner requiring plugins worked.
According to https://repology.org/repository/nix_unstable/problems, we have a
lot of packages that have http links that redirect to https as their homepage.
This commit updates all these packages to use the https links as their
homepage.
The following script was used to make these updates:
```
curl https://repology.org/api/v1/repository/nix_unstable/problems \
| jq '.[] | .problem' -r \
| rg 'Homepage link "(.+)" is a permanent redirect to "(.+)" and should be updated' --replace 's@$1@$2@' \
| sort | uniq > script.sed
find -name '*.nix' | xargs -P4 -- sed -f script.sed -i
```
