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-rw-r--r--lib/kernel/src/dist_util.erl474
1 files changed, 320 insertions, 154 deletions
diff --git a/lib/kernel/src/dist_util.erl b/lib/kernel/src/dist_util.erl
index b3507e5d13..ecc022b28d 100644
--- a/lib/kernel/src/dist_util.erl
+++ b/lib/kernel/src/dist_util.erl
@@ -1,7 +1,7 @@
%%
%% %CopyrightBegin%
%%
-%% Copyright Ericsson AB 1999-2017. All Rights Reserved.
+%% Copyright Ericsson AB 1999-2018. All Rights Reserved.
%%
%% Licensed under the Apache License, Version 2.0 (the "License");
%% you may not use this file except in compliance with the License.
@@ -27,8 +27,10 @@
%%-compile(export_all).
-export([handshake_we_started/1, handshake_other_started/1,
+ strict_order_flags/0,
start_timer/1, setup_timer/2,
reset_timer/1, cancel_timer/1,
+ is_node_name/1, split_node/1, is_allowed/2,
shutdown/3, shutdown/4]).
-import(error_logger,[error_msg/2]).
@@ -74,22 +76,52 @@
ticked = 0
}).
-remove_flag(Flag, Flags) ->
- case Flags band Flag of
- 0 ->
- Flags;
- _ ->
- Flags - Flag
- end.
+dflag2str(?DFLAG_PUBLISHED) ->
+ "PUBLISHED";
+dflag2str(?DFLAG_ATOM_CACHE) ->
+ "ATOM_CACHE";
+dflag2str(?DFLAG_EXTENDED_REFERENCES) ->
+ "EXTENDED_REFERENCES";
+dflag2str(?DFLAG_DIST_MONITOR) ->
+ "DIST_MONITOR";
+dflag2str(?DFLAG_FUN_TAGS) ->
+ "FUN_TAGS";
+dflag2str(?DFLAG_DIST_MONITOR_NAME) ->
+ "DIST_MONITOR_NAME";
+dflag2str(?DFLAG_HIDDEN_ATOM_CACHE) ->
+ "HIDDEN_ATOM_CACHE";
+dflag2str(?DFLAG_NEW_FUN_TAGS) ->
+ "NEW_FUN_TAGS";
+dflag2str(?DFLAG_EXTENDED_PIDS_PORTS) ->
+ "EXTENDED_PIDS_PORTS";
+dflag2str(?DFLAG_EXPORT_PTR_TAG) ->
+ "EXPORT_PTR_TAG";
+dflag2str(?DFLAG_BIT_BINARIES) ->
+ "BIT_BINARIES";
+dflag2str(?DFLAG_NEW_FLOATS) ->
+ "NEW_FLOATS";
+dflag2str(?DFLAG_UNICODE_IO) ->
+ "UNICODE_IO";
+dflag2str(?DFLAG_DIST_HDR_ATOM_CACHE) ->
+ "DIST_HDR_ATOM_CACHE";
+dflag2str(?DFLAG_SMALL_ATOM_TAGS) ->
+ "SMALL_ATOM_TAGS";
+dflag2str(?DFLAG_UTF8_ATOMS) ->
+ "UTF8_ATOMS";
+dflag2str(?DFLAG_MAP_TAG) ->
+ "MAP_TAG";
+dflag2str(?DFLAG_BIG_CREATION) ->
+ "BIG_CREATION";
+dflag2str(?DFLAG_SEND_SENDER) ->
+ "SEND_SENDER";
+dflag2str(?DFLAG_BIG_SEQTRACE_LABELS) ->
+ "BIG_SEQTRACE_LABELS";
+dflag2str(_) ->
+ "UNKNOWN".
+
adjust_flags(ThisFlags, OtherFlags) ->
- case (?DFLAG_PUBLISHED band ThisFlags) band OtherFlags of
- 0 ->
- {remove_flag(?DFLAG_PUBLISHED, ThisFlags),
- remove_flag(?DFLAG_PUBLISHED, OtherFlags)};
- _ ->
- {ThisFlags, OtherFlags}
- end.
+ ThisFlags band OtherFlags.
publish_flag(hidden, _) ->
0;
@@ -101,38 +133,56 @@ publish_flag(_, OtherNode) ->
0
end.
-make_this_flags(RequestType, OtherNode) ->
- publish_flag(RequestType, OtherNode) bor
- %% The parenthesis below makes the compiler generate better code.
- (?DFLAG_EXPORT_PTR_TAG bor
- ?DFLAG_EXTENDED_PIDS_PORTS bor
- ?DFLAG_EXTENDED_REFERENCES bor
- ?DFLAG_DIST_MONITOR bor
- ?DFLAG_FUN_TAGS bor
- ?DFLAG_DIST_MONITOR_NAME bor
- ?DFLAG_HIDDEN_ATOM_CACHE bor
- ?DFLAG_NEW_FUN_TAGS bor
- ?DFLAG_BIT_BINARIES bor
- ?DFLAG_NEW_FLOATS bor
- ?DFLAG_UNICODE_IO bor
- ?DFLAG_DIST_HDR_ATOM_CACHE bor
- ?DFLAG_SMALL_ATOM_TAGS bor
- ?DFLAG_UTF8_ATOMS bor
- ?DFLAG_MAP_TAG bor
- ?DFLAG_BIG_CREATION).
-
-handshake_other_started(#hs_data{request_type=ReqType}=HSData0) ->
+
+%% Sync with dist.c
+-record(erts_dflags, {
+ default, % flags erts prefers
+ mandatory, % flags erts needs
+ addable, % flags local dist implementation is allowed to add
+ rejectable, % flags local dist implementation is allowed to reject
+ strict_order % flags for features needing strict order delivery
+}).
+
+-spec strict_order_flags() -> integer().
+strict_order_flags() ->
+ EDF = erts_internal:get_dflags(),
+ EDF#erts_dflags.strict_order.
+
+make_this_flags(RequestType, AddFlags, RejectFlags, OtherNode,
+ #erts_dflags{}=EDF) ->
+ case RejectFlags band (bnot EDF#erts_dflags.rejectable) of
+ 0 -> ok;
+ Rerror -> exit({"Rejecting non rejectable flags", Rerror})
+ end,
+ case AddFlags band (bnot EDF#erts_dflags.addable) of
+ 0 -> ok;
+ Aerror -> exit({"Adding non addable flags", Aerror})
+ end,
+ Flgs0 = EDF#erts_dflags.default,
+ Flgs1 = Flgs0 bor publish_flag(RequestType, OtherNode),
+ Flgs2 = Flgs1 bor AddFlags,
+ Flgs2 band (bnot RejectFlags).
+
+handshake_other_started(#hs_data{request_type=ReqType,
+ add_flags=AddFlgs0,
+ reject_flags=RejFlgs0,
+ require_flags=ReqFlgs0}=HSData0) ->
+ AddFlgs = convert_flags(AddFlgs0),
+ RejFlgs = convert_flags(RejFlgs0),
+ ReqFlgs = convert_flags(ReqFlgs0),
{PreOtherFlags,Node,Version} = recv_name(HSData0),
- PreThisFlags = make_this_flags(ReqType, Node),
- {ThisFlags, OtherFlags} = adjust_flags(PreThisFlags,
- PreOtherFlags),
- HSData = HSData0#hs_data{this_flags=ThisFlags,
- other_flags=OtherFlags,
+ EDF = erts_internal:get_dflags(),
+ PreThisFlags = make_this_flags(ReqType, AddFlgs, RejFlgs, Node, EDF),
+ ChosenFlags = adjust_flags(PreThisFlags, PreOtherFlags),
+ HSData = HSData0#hs_data{this_flags=ChosenFlags,
+ other_flags=ChosenFlags,
other_version=Version,
other_node=Node,
- other_started=true},
- check_dflags(HSData),
- is_allowed(HSData),
+ other_started=true,
+ add_flags=AddFlgs,
+ reject_flags=RejFlgs,
+ require_flags=ReqFlgs},
+ check_dflags(HSData, EDF),
?debug({"MD5 connection from ~p (V~p)~n",
[Node, HSData#hs_data.other_version]}),
mark_pending(HSData),
@@ -150,38 +200,16 @@ handshake_other_started(OldHsData) when element(1,OldHsData) =:= hs_data ->
%%
-%% check if connecting node is allowed to connect
-%% with allow-node-scheme
-%%
-is_allowed(#hs_data{other_node = Node,
- allowed = Allowed} = HSData) ->
- case lists:member(Node, Allowed) of
- false when Allowed =/= [] ->
- send_status(HSData, not_allowed),
- error_msg("** Connection attempt from "
- "disallowed node ~w ** ~n", [Node]),
- ?shutdown2(Node, {is_allowed, not_allowed});
- _ -> true
- end.
-
-%%
-%% Check that both nodes can handle the same types of extended
-%% node containers. If they can not, abort the connection.
+%% Check mandatory flags...
%%
check_dflags(#hs_data{other_node = Node,
other_flags = OtherFlags,
- other_started = OtherStarted} = HSData) ->
-
- Mandatory = [{?DFLAG_EXTENDED_REFERENCES, "EXTENDED_REFERENCES"},
- {?DFLAG_EXTENDED_PIDS_PORTS, "EXTENDED_PIDS_PORTS"},
- {?DFLAG_UTF8_ATOMS, "UTF8_ATOMS"}],
- Missing = lists:filtermap(fun({Bit, Str}) ->
- case Bit band OtherFlags of
- Bit -> false;
- 0 -> {true, Str}
- end
- end,
- Mandatory),
+ other_started = OtherStarted,
+ require_flags = RequiredFlags} = HSData,
+ #erts_dflags{}=EDF) ->
+
+ Mandatory = (EDF#erts_dflags.mandatory bor RequiredFlags),
+ Missing = check_mandatory(Mandatory, OtherFlags, []),
case Missing of
[] ->
ok;
@@ -201,6 +229,21 @@ check_dflags(#hs_data{other_node = Node,
?shutdown2(Node, {check_dflags_failed, Missing})
end.
+check_mandatory(0, _OtherFlags, Missing) ->
+ Missing;
+check_mandatory(Mandatory, OtherFlags, Missing) ->
+ Left = Mandatory band (Mandatory - 1), % clear lowest set bit
+ DFlag = Mandatory bxor Left, % only lowest set bit
+ NewMissing = case DFlag band OtherFlags of
+ 0 ->
+ %% Mandatory and missing...
+ [dflag2str(DFlag) | Missing];
+ _ ->
+ %% Mandatory and present...
+ Missing
+ end,
+ check_mandatory(Left, OtherFlags, NewMissing).
+
%% No nodedown will be sent if we fail before this process has
%% succeeded to mark the node as pending.
@@ -314,17 +357,27 @@ flush_down() ->
end.
handshake_we_started(#hs_data{request_type=ReqType,
- other_node=Node}=PreHSData) ->
- PreThisFlags = make_this_flags(ReqType, Node),
- HSData = PreHSData#hs_data{this_flags=PreThisFlags},
+ other_node=Node,
+ add_flags=AddFlgs0,
+ reject_flags=RejFlgs0,
+ require_flags=ReqFlgs0}=PreHSData) ->
+ AddFlgs = convert_flags(AddFlgs0),
+ RejFlgs = convert_flags(RejFlgs0),
+ ReqFlgs = convert_flags(ReqFlgs0),
+ EDF = erts_internal:get_dflags(),
+ PreThisFlags = make_this_flags(ReqType, AddFlgs, RejFlgs, Node, EDF),
+ HSData = PreHSData#hs_data{this_flags = PreThisFlags,
+ add_flags = AddFlgs,
+ reject_flags = RejFlgs,
+ require_flags = ReqFlgs},
send_name(HSData),
recv_status(HSData),
{PreOtherFlags,ChallengeA} = recv_challenge(HSData),
- {ThisFlags,OtherFlags} = adjust_flags(PreThisFlags, PreOtherFlags),
- NewHSData = HSData#hs_data{this_flags = ThisFlags,
- other_flags = OtherFlags,
+ ChosenFlags = adjust_flags(PreThisFlags, PreOtherFlags),
+ NewHSData = HSData#hs_data{this_flags = ChosenFlags,
+ other_flags = ChosenFlags,
other_started = false},
- check_dflags(NewHSData),
+ check_dflags(NewHSData, EDF),
MyChallenge = gen_challenge(),
{MyCookie,HisCookie} = get_cookies(Node),
send_challenge_reply(NewHSData,MyChallenge,
@@ -336,15 +389,16 @@ handshake_we_started(#hs_data{request_type=ReqType,
handshake_we_started(OldHsData) when element(1,OldHsData) =:= hs_data ->
handshake_we_started(convert_old_hsdata(OldHsData)).
-convert_old_hsdata({hs_data, KP, ON, TN, S, T, TF, A, OV, OF, OS, FS, FR,
- FS_PRE, FS_POST, FG, FA, MFT, MFG, RT}) ->
- #hs_data{
- kernel_pid = KP, other_node = ON, this_node = TN, socket = S, timer = T,
- this_flags = TF, allowed = A, other_version = OV, other_flags = OF,
- other_started = OS, f_send = FS, f_recv = FR, f_setopts_pre_nodeup = FS_PRE,
- f_setopts_post_nodeup = FS_POST, f_getll = FG, f_address = FA,
- mf_tick = MFT, mf_getstat = MFG, request_type = RT}.
+convert_old_hsdata(OldHsData) ->
+ OHSDL = tuple_to_list(OldHsData),
+ NoMissing = tuple_size(#hs_data{}) - tuple_size(OldHsData),
+ true = NoMissing > 0,
+ list_to_tuple(OHSDL ++ lists:duplicate(NoMissing, undefined)).
+convert_flags(Flags) when is_integer(Flags) ->
+ Flags;
+convert_flags(_Undefined) ->
+ 0.
%% --------------------------------------------------------------
%% The connection has been established.
@@ -359,15 +413,20 @@ connection(#hs_data{other_node = Node,
PType = publish_type(HSData#hs_data.other_flags),
case FPreNodeup(Socket) of
ok ->
- do_setnode(HSData), % Succeeds or exits the process.
+ DHandle = do_setnode(HSData), % Succeeds or exits the process.
Address = FAddress(Socket,Node),
mark_nodeup(HSData,Address),
case FPostNodeup(Socket) of
ok ->
+ case HSData#hs_data.f_handshake_complete of
+ undefined -> ok;
+ HsComplete -> HsComplete(Socket, Node, DHandle)
+ end,
con_loop({HSData#hs_data.kernel_pid,
Node,
Socket,
PType,
+ DHandle,
HSData#hs_data.mf_tick,
HSData#hs_data.mf_getstat,
HSData#hs_data.mf_setopts,
@@ -425,18 +484,16 @@ do_setnode(#hs_data{other_node = Node, socket = Socket,
[Node, Port, {publish_type(Flags),
'(', Flags, ')',
Version}]),
- case (catch
- erlang:setnode(Node, Port,
- {Flags, Version, '', ''})) of
- {'EXIT', {system_limit, _}} ->
+ try
+ erlang:setnode(Node, Port, {Flags, Version, '', ''})
+ catch
+ error:system_limit ->
error_msg("** Distribution system limit reached, "
"no table space left for node ~w ** ~n",
[Node]),
?shutdown(Node);
- {'EXIT', Other} ->
- exit(Other);
- _Else ->
- ok
+ error:Other:Stacktrace ->
+ exit({Other, Stacktrace})
end;
_ ->
error_msg("** Distribution connection error, "
@@ -468,7 +525,13 @@ mark_nodeup(#hs_data{kernel_pid = Kernel,
?shutdown(Node)
end.
-con_loop({Kernel, Node, Socket, Type, MFTick, MFGetstat, MFSetOpts, MFGetOpts}=ConData,
+getstat(DHandle, _Socket, undefined) ->
+ erlang:dist_get_stat(DHandle);
+getstat(_DHandle, Socket, MFGetstat) ->
+ MFGetstat(Socket).
+
+con_loop({Kernel, Node, Socket, Type, DHandle, MFTick, MFGetstat,
+ MFSetOpts, MFGetOpts}=ConData,
Tick) ->
receive
{tcp_closed, Socket} ->
@@ -476,15 +539,15 @@ con_loop({Kernel, Node, Socket, Type, MFTick, MFGetstat, MFSetOpts, MFGetOpts}=C
{Kernel, disconnect} ->
?shutdown2(Node, disconnected);
{Kernel, aux_tick} ->
- case MFGetstat(Socket) of
+ case getstat(DHandle, Socket, MFGetstat) of
{ok, _, _, PendWrite} ->
- send_tick(Socket, PendWrite, MFTick);
+ send_aux_tick(Type, Socket, PendWrite, MFTick);
_ ->
ignore_it
end,
con_loop(ConData, Tick);
{Kernel, tick} ->
- case send_tick(Socket, Tick, Type,
+ case send_tick(DHandle, Socket, Tick, Type,
MFTick, MFGetstat) of
{ok, NewTick} ->
con_loop(ConData, NewTick);
@@ -497,7 +560,7 @@ con_loop({Kernel, Node, Socket, Type, MFTick, MFGetstat, MFSetOpts, MFGetOpts}=C
?shutdown2(Node, send_net_tick_failed)
end;
{From, get_status} ->
- case MFGetstat(Socket) of
+ case getstat(DHandle, Socket, MFGetstat) of
{ok, Read, Write, _} ->
From ! {self(), get_status, {ok, Read, Write}},
con_loop(ConData, Tick);
@@ -564,33 +627,130 @@ send_challenge_ack(#hs_data{socket = Socket, f_send = FSend},
%% tcp_drv.c which used it to detect simultaneous connection
%% attempts).
%%
-recv_name(#hs_data{socket = Socket, f_recv = Recv}) ->
+recv_name(#hs_data{socket = Socket, f_recv = Recv} = HSData) ->
case Recv(Socket, 0, infinity) of
- {ok,Data} ->
- get_name(Data);
+ {ok,
+ [$n,VersionA, VersionB, Flag1, Flag2, Flag3, Flag4
+ | OtherNode] = Data} ->
+ case is_node_name(OtherNode) of
+ true ->
+ Flags = ?u32(Flag1, Flag2, Flag3, Flag4),
+ Version = ?u16(VersionA,VersionB),
+ is_allowed(HSData, Flags, OtherNode, Version);
+ false ->
+ ?shutdown(Data)
+ end;
_ ->
?shutdown(no_node)
end.
-get_name([$n,VersionA, VersionB, Flag1, Flag2, Flag3, Flag4 | OtherNode] = Data) ->
- case is_valid_name(OtherNode) of
+is_node_name(OtherNodeName) ->
+ case string:split(OtherNodeName, "@", all) of
+ [Name,Host] ->
+ (not string:is_empty(Name))
+ andalso (not string:is_empty(Host));
+ _ ->
+ false
+ end.
+
+split_node(Node) ->
+ Split = string:split(listify(Node), "@", all),
+ case Split of
+ [Name,Host] ->
+ case string:is_empty(Name) of
+ true ->
+ Split;
+ false ->
+ case string:is_empty(Host) of
+ true ->
+ {name,Name};
+ false ->
+ {node,Name,Host}
+ end
+ end;
+ [Host] ->
+ case string:is_empty(Host) of
+ true ->
+ Split;
+ false ->
+ {host,Host}
+ end
+ end.
+
+%% Check if connecting node is allowed to connect
+%% with allow-node-scheme. An empty allowed list
+%% allows all nodes.
+%%
+is_allowed(#hs_data{allowed = []}, Flags, Node, Version) ->
+ {Flags,list_to_atom(Node),Version};
+is_allowed(#hs_data{allowed = Allowed} = HSData, Flags, Node, Version) ->
+ case is_allowed(Node, Allowed) of
true ->
- {?u32(Flag1, Flag2, Flag3, Flag4), list_to_atom(OtherNode),
- ?u16(VersionA,VersionB)};
+ {Flags,list_to_atom(Node),Version};
false ->
- ?shutdown(Data)
- end;
-get_name(Data) ->
- ?shutdown(Data).
-
-is_valid_name(OtherNodeName) ->
- case string:lexemes(OtherNodeName,"@") of
- [_OtherNodeName,_OtherNodeHost] ->
- true;
- _else ->
- false
+ send_status(HSData#hs_data{other_node = Node}, not_allowed),
+ error_msg("** Connection attempt from "
+ "disallowed node ~s ** ~n", [Node]),
+ ?shutdown2(Node, {is_allowed, not_allowed})
+ end.
+
+%% The allowed list can contain node names, host names
+%% or names before '@', in atom or list form:
+%% [[email protected], "host.example.org", "node@"].
+%% An empty allowed list allows no nodes.
+%%
+%% Allow a node that matches any entry in the allowed list.
+%% Also allow allowed entries as node to match, not from
+%% this module; here the node has to be a valid name.
+%%
+is_allowed(_Node, []) ->
+ false;
+is_allowed(Node, [Node|_Allowed]) ->
+ %% Just an optimization
+ true;
+is_allowed(Node, [AllowedNode|Allowed]) ->
+ case split_node(AllowedNode) of
+ {node,AllowedName,AllowedHost} ->
+ %% Allowed node name
+ case split_node(Node) of
+ {node,AllowedName,AllowedHost} ->
+ true;
+ _ ->
+ is_allowed(Node, Allowed)
+ end;
+ {host,AllowedHost} ->
+ %% Allowed host name
+ case split_node(Node) of
+ {node,_,AllowedHost} ->
+ %% Matching Host part
+ true;
+ {host,AllowedHost} ->
+ %% Host matches Host
+ true;
+ _ ->
+ is_allowed(Node, Allowed)
+ end;
+ {name,AllowedName} ->
+ %% Allowed name before '@'
+ case split_node(Node) of
+ {node,AllowedName,_} ->
+ %% Matching Name part
+ true;
+ {name,AllowedName} ->
+ %% Name matches Name
+ true;
+ _ ->
+ is_allowed(Node, Allowed)
+ end;
+ _ ->
+ is_allowed(Node, Allowed)
end.
+listify(Atom) when is_atom(Atom) ->
+ atom_to_list(Atom);
+listify(Node) when is_list(Node) ->
+ Node.
+
publish_type(Flags) ->
case Flags band ?DFLAG_PUBLISHED of
0 ->
@@ -731,51 +891,57 @@ send_status(#hs_data{socket = Socket, other_node = Node,
%% The detection time interval is thus, by default, 45s < DT < 75s
-%% A HIDDEN node is always (if not a pending write) ticked if
-%% we haven't read anything as a hidden node only ticks when it receives
-%% a TICK !!
+%% A HIDDEN node is always ticked if we haven't read anything
+%% as a (primitive) hidden node only ticks when it receives a TICK !!
-send_tick(Socket, Tick, Type, MFTick, MFGetstat) ->
+send_tick(DHandle, Socket, Tick, Type, MFTick, MFGetstat) ->
#tick{tick = T0,
read = Read,
write = Write,
- ticked = Ticked} = Tick,
+ ticked = Ticked0} = Tick,
T = T0 + 1,
T1 = T rem 4,
- case MFGetstat(Socket) of
- {ok, Read, _, _} when Ticked =:= T ->
+ case getstat(DHandle, Socket, MFGetstat) of
+ {ok, Read, _, _} when Ticked0 =:= T ->
{error, not_responding};
- {ok, Read, W, Pend} when Type =:= hidden ->
- send_tick(Socket, Pend, MFTick),
- {ok, Tick#tick{write = W + 1,
- tick = T1}};
- {ok, Read, Write, Pend} ->
- send_tick(Socket, Pend, MFTick),
- {ok, Tick#tick{write = Write + 1,
- tick = T1}};
- {ok, R, Write, Pend} ->
- send_tick(Socket, Pend, MFTick),
- {ok, Tick#tick{write = Write + 1,
- read = R,
- tick = T1,
- ticked = T}};
- {ok, Read, W, _} ->
- {ok, Tick#tick{write = W,
- tick = T1}};
- {ok, R, W, _} ->
- {ok, Tick#tick{write = W,
- read = R,
- tick = T1,
- ticked = T}};
+
+ {ok, R, W1, Pend} ->
+ RDiff = R - Read,
+ W2 = case need_to_tick(Type, RDiff, W1-Write, Pend) of
+ true ->
+ MFTick(Socket),
+ W1 + 1;
+ false ->
+ W1
+ end,
+
+ Ticked1 = case RDiff of
+ 0 -> Ticked0;
+ _ -> T
+ end,
+
+ {ok, Tick#tick{write = W2,
+ tick = T1,
+ read = R,
+ ticked = Ticked1}};
+
Error ->
Error
end.
-send_tick(Socket, 0, MFTick) ->
- MFTick(Socket);
-send_tick(_, _Pend, _) ->
- %% Dont send tick if pending write.
- ok.
+need_to_tick(_, _, 0, 0) -> % nothing written and empty send queue
+ true;
+need_to_tick(_, _, 0, false) -> % nothing written and empty send queue
+ true;
+need_to_tick(hidden, 0, _, _) -> % nothing read from hidden
+ true;
+need_to_tick(_, _, _, _) ->
+ false.
+
+send_aux_tick(normal, _, Pend, _) when Pend /= false, Pend /= 0 ->
+ ok; %% Dont send tick if pending write.
+send_aux_tick(_Type, Socket, _Pend, MFTick) ->
+ MFTick(Socket).
%% ------------------------------------------------------------
%% Connection setup timeout timer.