# HG changeset patch # User Matthew Wild # Date 1236171575 0 # Node ID 4fd5d8f1657cc0270c4ea2dd1d1cbd80f4bf2f97 # Parent 09019c4527094f72643b3ffe451047383b65dd26 net.adns: Add helper module for performing non-blocking DNS lookups diff -r 09019c452709 -r 4fd5d8f1657c net/adns.lua --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/net/adns.lua Wed Mar 04 12:59:35 2009 +0000 @@ -0,0 +1,38 @@ +local server = require "net.server"; +local dns = require "net.dns2"; + +local log = require "util.logger".init("adns"); + +local coroutine, tostring = coroutine, tostring; + +module "adns" + +function lookup(handler, qname, qtype, qclass) + return dns.peek(qname, qtype, qclass) or + coroutine.wrap(function () + log("debug", "Records for "..qname.." not in cache, sending query (%s)...", tostring(coroutine.running())); + dns.query(qname, qtype, qclass); + coroutine.yield(nil); -- Wait for reply + log("debug", "Reply for "..qname.." (%s)", tostring(coroutine.running())); + handler(dns.peek(qname, qtype, qclass)); + end)(); +end + +function new_async_socket(sock) + local newconn = {}; + local listener = {}; + function listener.incoming(conn, data) + dns.feed(sock, data); + end + function listener.disconnect() + end + newconn.handler, newconn._socket = server.wrapclient(sock, "dns", 53, listener); + newconn.handler.settimeout = function () end + newconn.handler.setsockname = function (_, ...) return sock:setsockname(...); end + newconn.handler.setpeername = function (_, ...) return sock:setpeername(...); end + newconn.handler.connect = function (_, ...) return sock:connect(...) end + newconn.handler.send = function (_, data) return _.write(data) end + return newconn.handler; +end + +dns:socket_wrapper_set(new_async_socket);