Mercurial > mjpegproxy / file comparison
comparison: net/adns.lua
net/adns.lua
- changeset 0
- d363a6692a10
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| -1:000000000000 | 0:d363a6692a10 |
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| 1 -- Prosody IM | |
| 2 -- Copyright (C) 2008-2010 Matthew Wild | |
| 3 -- Copyright (C) 2008-2010 Waqas Hussain | |
| 4 -- | |
| 5 -- This project is MIT/X11 licensed. Please see the | |
| 6 -- COPYING file in the source package for more information. | |
| 7 -- | |
| 8 | |
| 9 local server = require "net.server"; | |
| 10 local dns = require "net.dns"; | |
| 11 | |
| 12 local log = require "util.logger".init("adns"); | |
| 13 | |
| 14 local t_insert, t_remove = table.insert, table.remove; | |
| 15 local coroutine, tostring, pcall = coroutine, tostring, pcall; | |
| 16 | |
| 17 local function dummy_send(sock, data, i, j) return (j-i)+1; end | |
| 18 | |
| 19 module "adns" | |
| 20 | |
| 21 function lookup(handler, qname, qtype, qclass) | |
| 22 return coroutine.wrap(function (peek) | |
| 23 if peek then | |
| 24 log("debug", "Records for %s already cached, using those...", qname); | |
| 25 handler(peek); | |
| 26 return; | |
| 27 end | |
| 28 log("debug", "Records for %s not in cache, sending query (%s)...", qname, tostring(coroutine.running())); | |
| 29 local ok, err = dns.query(qname, qtype, qclass); | |
| 30 if ok then | |
| 31 coroutine.yield({ qclass or "IN", qtype or "A", qname, coroutine.running()}); -- Wait for reply | |
| 32 log("debug", "Reply for %s (%s)", qname, tostring(coroutine.running())); | |
| 33 end | |
| 34 if ok then | |
| 35 ok, err = pcall(handler, dns.peek(qname, qtype, qclass)); | |
| 36 else | |
| 37 log("error", "Error sending DNS query: %s", err); | |
| 38 ok, err = pcall(handler, nil, err); | |
| 39 end | |
| 40 if not ok then | |
| 41 log("error", "Error in DNS response handler: %s", tostring(err)); | |
| 42 end | |
| 43 end)(dns.peek(qname, qtype, qclass)); | |
| 44 end | |
| 45 | |
| 46 function cancel(handle, call_handler, reason) | |
| 47 log("warn", "Cancelling DNS lookup for %s", tostring(handle[3])); | |
| 48 dns.cancel(handle[1], handle[2], handle[3], handle[4], call_handler); | |
| 49 end | |
| 50 | |
| 51 function new_async_socket(sock, resolver) | |
| 52 local peername = "<unknown>"; | |
| 53 local listener = {}; | |
| 54 local handler = {}; | |
| 55 local err; | |
| 56 function listener.onincoming(conn, data) | |
| 57 if data then | |
| 58 dns.feed(handler, data); | |
| 59 end | |
| 60 end | |
| 61 function listener.ondisconnect(conn, err) | |
| 62 if err then | |
| 63 log("warn", "DNS socket for %s disconnected: %s", peername, err); | |
| 64 local servers = resolver.server; | |
| 65 if resolver.socketset[conn] == resolver.best_server and resolver.best_server == #servers then | |
| 66 log("error", "Exhausted all %d configured DNS servers, next lookup will try %s again", #servers, servers[1]); | |
| 67 end | |
| 68 | |
| 69 resolver:servfail(conn); -- Let the magic commence | |
| 70 end | |
| 71 end | |
| 72 handler, err = server.wrapclient(sock, "dns", 53, listener); | |
| 73 if not handler then | |
| 74 return nil, err; | |
| 75 end | |
| 76 | |
| 77 handler.settimeout = function () end | |
| 78 handler.setsockname = function (_, ...) return sock:setsockname(...); end | |
| 79 handler.setpeername = function (_, ...) peername = (...); local ret, err = sock:setpeername(...); _:set_send(dummy_send); return ret, err; end | |
| 80 handler.connect = function (_, ...) return sock:connect(...) end | |
| 81 --handler.send = function (_, data) _:write(data); return _.sendbuffer and _.sendbuffer(); end | |
| 82 handler.send = function (_, data) | |
| 83 log("debug", "Sending DNS query to %s", peername); | |
| 84 return sock:send(data); | |
| 85 end | |
| 86 return handler; | |
| 87 end | |
| 88 | |
| 89 dns.socket_wrapper_set(new_async_socket); | |
| 90 | |
| 91 return _M; |
