net: isolate LuaSec-specifics For this, various accessor functions are now provided directly on the sockets, which reach down into the LuaSec implementation to obtain the information. While this may seem of little gain at first, it hides the implementation detail of the LuaSec+LuaSocket combination that the actual socket and the TLS layer are separate objects. The net gain here is that an alternative implementation does not have to emulate that specific implementation detail and "only" has to expose LuaSec-compatible data structures on the new functions.

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");