samba4: add default dnssd variant

[CL-Jeremy]

• port Bonjour via mDNSResponder from FreeBSD and use as standard variant for Darwin

Description

Type(s)

• bugfix
• enhancement
• security fix

Tested on

macOS 10.15.7 19H2026 x86_64
Command Line Tools 12.4.0.0.1.1610135815
macOS 15.4.1 24E263 x86_64
Command Line Tools 16.3.0.0.1.1742442376

Verification

Have you

• followed our Commit Message Guidelines?
• squashed and minimized your commits?
• checked that there aren't other open pull requests for the same change?
• referenced existing tickets on Trac with full URL in commit message?
• checked your Portfile with port lint?
• tried existing tests with sudo port test?
• tried a full install with sudo port -vst install?
• tested basic functionality of all binary files?
• checked that the Portfile's most important variants haven't been broken?

[CL-Jeremy]

Just a sec, I'll try to fix ls-qpack first so this builds on 10.7-10.9.

[reneeotten]

was this accepted upstream? We typically don't want to be in the business of carrying forward large patches that are not supported by upstream.

[CL-Jeremy]

was this accepted upstream? We typically don't want to be in the business of carrying forward large patches that are not supported by upstream.

Generally agree, but:

• The original implementation comes from Samba itself (2007, Samba 3) and was used extensively (Mac OS X used to ship Samba), and Darwin is where this patch makes the most sense by far
• The original implementation was broken due to many upstream refactorings (some were done through scripts)
• Upstream has an open pull request (!1140) – and a closed one (!1134) where the removal of the relevant code basis was rejected – so the usage of this patch is at least recognized by upstream (so far it's been working for many major releases without modification)
  • the PR was not rejected, it just needed some fixes, which are covered by this patch
• FreeBSD has been supporting this patch for quite long (over 7 years), where the maintainer there (Timur I. Bakeyev) was affiliated with the source of this patch (TrueNAS) and has great insights in the software itself
• mDNSResponder is fully open-source and its API is quite stable, so it's also highly unlikely that things break on this side, either

Since this software is pretty useful for me, I could become a maintainer for this port in MacPorts, if this could help with the situation. I think FreeBSD is a pretty reliable source of inspiration for this port.