Replace the custom DNS servers used in the "chain" system test with
new code based on the isctest.asyncserver module.
For ans3, replace the sequence of logical conditions present in Perl
code with zone files and a limited amount of custom logic applied on top
of them where necessary.
For ans4, replace the ctl_channel() and create_response() functions with
a custom control command handler coupled with a dynamically instantiated
response handler, making the code more robust and readable.
Migrate sendcmd() and its uses to the new way of sending control queries
to custom servers used in system tests.
This commit converts the license handling to adhere to the REUSE
specification. It specifically:
1. Adds used licnses to LICENSES/ directory
2. Add "isc" template for adding the copyright boilerplate
3. Changes all source files to include copyright and SPDX license
header, this includes all the C sources, documentation, zone files,
configuration files. There are notes in the doc/dev/copyrights file
on how to add correct headers to the new files.
4. Handle the rest that can't be modified via .reuse/dep5 file. The
binary (or otherwise unmodifiable) files could have license places
next to them in <foo>.license file, but this would lead to cluttered
repository and most of the files handled in the .reuse/dep5 file are
system test files.
- add CHANGES note
- update copyrights and license headers
- add -j to the make commands in .gitlab-ci.yml to take
advantage of parallelization in the gitlab CI process
