From 291644e89541f87496c44aacf21ae7a228d1f018 Mon Sep 17 00:00:00 2001 From: Raimo Niskanen Date: Wed, 13 Apr 2011 18:17:23 +0200 Subject: Cleanup timeout handling, fix bug for remaining time =:= 0 --- lib/kernel/src/inet_res.erl | 166 +++++++++++++++++++++++++------------------- 1 file changed, 95 insertions(+), 71 deletions(-) (limited to 'lib') diff --git a/lib/kernel/src/inet_res.erl b/lib/kernel/src/inet_res.erl index de0f23bf24..2b63121043 100644 --- a/lib/kernel/src/inet_res.erl +++ b/lib/kernel/src/inet_res.erl @@ -1,7 +1,7 @@ %% %% %CopyrightBegin% %% -%% Copyright Ericsson AB 1997-2010. All Rights Reserved. +%% Copyright Ericsson AB 1997-2011. All Rights Reserved. %% %% The contents of this file are subject to the Erlang Public License, %% Version 1.1, (the "License"); you may not use this file except in @@ -539,27 +539,34 @@ udp_send(#sock{inet=I}, {A,B,C,D}=IP, Port, Buffer) when ?ip(A,B,C,D), ?port(Port) -> gen_udp:send(I, IP, Port, Buffer). -udp_recv(#sock{inet6=I}, {A,B,C,D,E,F,G,H}=IP, Port, Timeout) +udp_recv(#sock{inet6=I}, {A,B,C,D,E,F,G,H}=IP, Port, Timeout, Decode) when ?ip6(A,B,C,D,E,F,G,H), ?port(Port) -> - do_udp_recv(fun(T) -> gen_udp:recv(I, 0, T) end, IP, Port, Timeout); -udp_recv(#sock{inet=I}, {A,B,C,D}=IP, Port, Timeout) + do_udp_recv(I, IP, Port, Timeout, Decode); +udp_recv(#sock{inet=I}, {A,B,C,D}=IP, Port, Timeout, Decode) when ?ip(A,B,C,D), ?port(Port) -> - do_udp_recv(fun(T) -> gen_udp:recv(I, 0, T) end, IP, Port, Timeout). - -do_udp_recv(Recv, IP, Port, Timeout) -> - do_udp_recv(Recv, IP, Port, Timeout, - if Timeout =/= 0 -> erlang:now(); true -> undefined end). - -do_udp_recv(Recv, IP, Port, Timeout, Then) -> - case Recv(Timeout) of - {ok,{IP,Port,Answer}} -> - {ok,Answer,erlang:max(0, Timeout - now_ms(erlang:now(), Then))}; - {ok,_} when Timeout =:= 0 -> - {error,timeout}; - {ok,_} -> - Now = erlang:now(), - T = erlang:max(0, Timeout - now_ms(Now, Then)), - do_udp_recv(Recv, IP, Port, T, Now); + do_udp_recv(I, IP, Port, Timeout, Decode). + +do_udp_recv(I, IP, Port, Timeout, Decode) -> + Start = + case Timeout of + 0 -> undefined; + _ -> erlang:now() + end, + do_udp_recv(I, IP, Port, Timeout, Decode, Start, Timeout). + +do_udp_recv(I, IP, Port, Timeout, Decode, Start, T) -> + case gen_udp:recv(I, 0, T) of + {ok,Reply} -> + case Decode(Reply) of + false when Start =:= undefined -> + do_udp_recv(I, IP, Port, Timeout, Decode, Start, T); + false -> + Now = erlang:now(), + NewT = erlang:max(0, Timeout - now_ms(Now, Start)), + do_udp_recv(I, IP, Port, Timeout, Decode, Start, NewT); + Result -> + Result + end; Error -> Error end. @@ -580,6 +587,17 @@ udp_close(#sock{inet=I,inet6=I6}) -> %% end %% end %% +%% But that man page also says dig always use num_servers = 1. +%% +%% Our man page says: timeout/retry, then double for next retry, i.e +%% for i = 0 to retry - 1 +%% foreach nameserver +%% send query +%% wait((time * (2**i)) / retry) +%% end +%% end +%% +%% And that is what the code seems to do, now fixed, hopefully... do_query(_Q, [], _Timer) -> {error,nxdomain}; @@ -589,19 +607,16 @@ do_query(#q{options=#options{retry=Retry}}=Q, NSs, Timer) -> query_retries(_Q, _NSs, _Timer, Retry, Retry, S) -> udp_close(S), {error,timeout}; +query_retries(_Q, [], _Timer, _Retry, _I, S) -> + udp_close(S), + {error,timeout}; query_retries(Q, NSs, Timer, Retry, I, S0) -> - Num = length(NSs), - if Num =:= 0 -> - udp_close(S0), - {error,timeout}; - true -> - case query_nss(Q, NSs, Timer, Retry, I, S0, []) of - {S,{noanswer,ErrNSs}} -> %% remove unreachable nameservers - query_retries(Q, NSs--ErrNSs, Timer, Retry, I+1, S); - {S,Result} -> - udp_close(S), - Result - end + case query_nss(Q, NSs, Timer, Retry, I, S0, []) of + {S,{noanswer,ErrNSs}} -> %% remove unreachable nameservers + query_retries(Q, NSs--ErrNSs, Timer, Retry, I+1, S); + {S,Result} -> + udp_close(S), + Result end. query_nss(_Q, [], _Timer, _Retry, _I, S, ErrNSs) -> @@ -611,13 +626,13 @@ query_nss(#q{edns=undefined}=Q, NSs, Timer, Retry, I, S, ErrNSs) -> query_nss(Q, NSs, Timer, Retry, I, S, ErrNSs) -> query_nss_edns(Q, NSs, Timer, Retry, I, S, ErrNSs). -query_nss_edns(#q{options=#options{udp_payload_size=PSz}=Options, - edns={Id,Buffer}}=Q, - [{IP,Port}=NS|NSs]=NSs0, Timer, Retry, I, S0, ErrNSs) -> - {S,Res}=Reply = query_ns(S0, Id, Buffer, IP, Port, Timer, - Retry, I, Options, PSz), +query_nss_edns( + #q{options=#options{udp_payload_size=PSz}=Options,edns={Id,Buffer}}=Q, + [{IP,Port}=NS|NSs]=NSs0, Timer, Retry, I, S0, ErrNSs) -> + {S,Res}=Reply = + query_ns(S0, Id, Buffer, IP, Port, Timer, Retry, I, Options, PSz), case Res of - timeout -> {S,{error,timeout}}; + timeout -> {S,{error,timeout}}; % Bailout timeout {ok,_} -> Reply; {error,{nxdomain,_}} -> Reply; {error,{E,_}} when E =:= qfmterror; E =:= notimp; E =:= servfail; @@ -629,17 +644,19 @@ query_nss_edns(#q{options=#options{udp_payload_size=PSz}=Options, query_nss(Q, NSs, Timer, Retry, I, S, ErrNSs) end. -query_nss_dns(#q{dns=Qdns}=Q0, [{IP,Port}=NS|NSs], - Timer, Retry, I, S0, ErrNSs) -> +query_nss_dns( + #q{dns=Qdns}=Q0, + [{IP,Port}=NS|NSs], Timer, Retry, I, S0, ErrNSs) -> #q{options=Options,dns={Id,Buffer}}=Q = if is_function(Qdns, 0) -> Q0#q{dns=Qdns()}; true -> Q0 end, - {S,Res}=Reply = query_ns(S0, Id, Buffer, IP, Port, Timer, - Retry, I, Options, ?PACKETSZ), + {S,Res}=Reply = + query_ns( + S0, Id, Buffer, IP, Port, Timer, Retry, I, Options, ?PACKETSZ), case Res of - timeout -> {S,{error,timeout}}; + timeout -> {S,{error,timeout}}; % Bailout timeout {ok,_} -> Reply; {error,{E,_}} when E =:= nxdomain; E =:= qfmterror -> Reply; {error,E} when E =:= fmt; E =:= enetunreach; E =:= econnrefused -> @@ -653,48 +670,55 @@ query_ns(S0, Id, Buffer, IP, Port, Timer, Retry, I, PSz) -> case UseVC orelse iolist_size(Buffer) > PSz of true -> - {S0,query_tcp(Tm, Id, Buffer, IP, Port, Timer, Verbose)}; + TcpTimeout = inet:timeout(Tm*5, Timer), + {S0,query_tcp(TcpTimeout, Id, Buffer, IP, Port, Verbose)}; false -> case udp_open(S0, IP) of {ok,S} -> - {S,case query_udp(S, Id, Buffer, IP, Port, Timer, - Retry, I, Tm, Verbose) of - {ok,#dns_rec{header=H}} when H#dns_header.tc -> - query_tcp(Tm, Id, Buffer, - IP, Port, Timer, Verbose); - Reply -> Reply - end}; + Timeout = + inet:timeout( (Tm * (1 bsl I)) div Retry, Timer), + {S, + case query_udp( + S, Id, Buffer, IP, Port, Timeout, Verbose) of + {ok,#dns_rec{header=H}} when H#dns_header.tc -> + TcpTimeout = inet:timeout(Tm*5, Timer), + query_tcp( + TcpTimeout, Id, Buffer, IP, Port, Verbose); + Reply -> Reply + end}; Error -> {S0,Error} end end. -query_udp(S, Id, Buffer, IP, Port, Timer, Retry, I, Tm, Verbose) -> - Timeout = inet:timeout( (Tm * (1 bsl I)) div Retry, Timer), +query_udp(S, Id, Buffer, IP, Port, Timeout, Verbose) -> ?verbose(Verbose, "Try UDP server : ~p:~p (timeout=~w)\n", - [IP, Port, Timeout]), + [IP,Port,Timeout]), udp_connect(S, IP, Port), udp_send(S, IP, Port, Buffer), - query_udp_recv(S, IP, Port, Id, Timeout, Verbose). - -query_udp_recv(S, IP, Port, Id, Timeout, Verbose) -> - case udp_recv(S, IP, Port, Timeout) of - {ok,Answer,T} -> - case decode_answer(Answer, Id, Verbose) of - {error, badid} -> - query_udp_recv(S, IP, Port, Id, T, Verbose); - Reply -> Reply - end; - {error, timeout} when Timeout =:= 0 -> - ?verbose(Verbose, "UDP server timeout\n", []), + Decode = + fun ({RecIP,RecPort,Answer}) when RecIP =:= IP, RecPort =:= Port -> + case decode_answer(Answer, Id, Verbose) of + {error,badid} -> + false; + Reply -> + Reply + end; + ({_,_,_}) -> + false + end, + case udp_recv(S, IP, Port, Timeout, Decode) of + {ok,_}=Result -> + Result; + {error,timeout} when Timeout =:= 0 -> + ?verbose(Verbose, "UDP bailout timeout\n", []), timeout; - Error -> + Error -> ?verbose(Verbose, "UDP server error: ~p\n", [Error]), Error end. -query_tcp(Tm, Id, Buffer, IP, Port, Timer, Verbose) -> - Timeout = inet:timeout(Tm*5, Timer), +query_tcp(Timeout, Id, Buffer, IP, Port, Verbose) -> ?verbose(Verbose, "Try TCP server : ~p:~p (timeout=~w)\n", [IP, Port, Timeout]), Family = case IP of @@ -718,7 +742,7 @@ query_tcp(Tm, Id, Buffer, IP, Port, Timer, Verbose) -> gen_tcp:close(S), case Error of {error, timeout} when Timeout =:= 0 -> - ?verbose(Verbose, "TCP server recv timeout\n", []), + ?verbose(Verbose, "TCP bailout recv timeout\n", []), timeout; _ -> ?verbose(Verbose, "TCP server recv error: ~p\n", @@ -727,7 +751,7 @@ query_tcp(Tm, Id, Buffer, IP, Port, Timer, Verbose) -> end end; {error, timeout} when Timeout =:= 0 -> - ?verbose(Verbose, "TCP server connect timeout\n", []), + ?verbose(Verbose, "TCP bailout connect timeout\n", []), timeout; Error -> ?verbose(Verbose, "TCP server error: ~p\n", [Error]), -- cgit v1.2.3