net: refactor sslconfig to not depend on LuaSec This now requires that the network backend exposes a tls_builder function, which essentially wraps the former util.sslconfig.new() function, passing a factory to create the eventual SSL context. That allows a net.server backend to pick whatever it likes as SSL context factory, as long as it understands the config table passed by the SSL config builder. Heck, a backend could even mock and replace the entire SSL config builder API.

local data = {}
local getinfo = debug.getinfo;
local function linehook(ev, li)
	local S = getinfo(2, "S");
	if S and S.source and S.source:match"^@" then
		local file = S.source:sub(2);
		local lines = data[file];
		if not lines then
			lines = {};
			data[file] = lines;
			for line in io.lines(file) do
				lines[#lines+1] = line;
			end
		end
		io.stderr:write(ev, " ", file, " ", li, " ", lines[li], "\n");
	end
end
debug.sethook(linehook, "l");