[socket-nif] Add proper connect and accept timeout handling

Added proper connect and accept timeout handling.
Made use of the enif_select(mode = cancel) feature. Each
time a timeout expires, the previous operation (connect or accept)
has to be cancelled (actually its the select operation that has
to be cancelled). Only partial implementation of cancel for now
(connect and accept). More to follow...

OTP-14831

2 files changed, 25 insertions, 6 deletions

diff --git a/lib/kernel/test/socket_client.erl b/lib/kernel/test/socket_client.erl
index 58d70b6181..6cd353fd07 100644
--- a/lib/kernel/test/socket_client.erl
+++ b/lib/kernel/test/socket_client.erl
@@ -74,7 +74,7 @@ start(Domain, Type, Proto, Addr, Port) ->
     %% The way we use tos only works because we
     %% send so few messages (a new value for every
     %% message).
-    put(tos, 1),
+    tos_init(),
     do_start(Domain, Type, Proto, SA).
 
 do_start(Domain, stream = Type, Proto, SA) ->
@@ -282,11 +282,10 @@ send(#client{socket = Sock, type = dgram, dest = Dest}, Msg) ->
     %% i("try send to: "
     %%   "~n   ~p", [Dest]),
     %% ok = socket:setopt(Sock, otp, debug, true),
-    TOS = get(tos),
+    TOS = tos_next(),
     ok = socket:setopt(Sock, ip, tos, TOS),
     case socket:sendto(Sock, Msg, Dest) of
         ok = OK ->
-            put(tos, TOS+1),
             OK;
         {error, _} = ERROR ->
             ERROR
@@ -402,6 +401,22 @@ which_addr2(Domain, [_|IFO]) ->
 
 %% ---
 
+tos_init() ->
+    put(tos, 1).
+
+tos_next() ->
+    case get(tos) of
+        TOS when (TOS < 100) ->
+            put(tos, TOS + 1),
+            TOS;
+        _ ->
+            put(tos, 1),
+            1
+    end.
+
+
+%% ---
+
 e(F, A) ->
     ?LIB:e(F, A).
 
diff --git a/lib/kernel/test/socket_server.erl b/lib/kernel/test/socket_server.erl
index ea2bdc8e0d..3e5c4e5d95 100644
--- a/lib/kernel/test/socket_server.erl
+++ b/lib/kernel/test/socket_server.erl
@@ -34,7 +34,7 @@
 -define(LIB, socket_lib).
 
 -record(manager,  {socket, msg, peek, acceptors, handler_id, handlers}).
--record(acceptor, {id, socket, manager}).
+-record(acceptor, {id, socket, manager, atimeout = 5000}).
 -record(handler,  {socket, peek, msg, type, manager}).
 
 -define(NUM_ACCEPTORS, 5).
@@ -521,13 +521,14 @@ acceptor_stop(Pid, _Reason) ->
 acceptor_init(Manager, Sock, ID) ->
     put(sname, f("acceptor[~w]", [ID])),
     Manager ! {acceptor, self(), ok},
+    %% ok = socket:setopt(Sock, otp, debug, true),
     acceptor_loop(#acceptor{id      = ID,
                             manager = Manager,
                             socket  = Sock}).
 
-acceptor_loop(#acceptor{socket = LSock} = A) ->
+acceptor_loop(#acceptor{socket = LSock, atimeout = Timeout} = A) ->
     i("try accept"),
-    case socket:accept(LSock, infinity) of
+    case socket:accept(LSock, Timeout) of
         {ok, Sock} ->
             i("accepted: "
               "~n   ~p"
@@ -542,6 +543,9 @@ acceptor_loop(#acceptor{socket = LSock} = A) ->
                     socket:close(Sock),
                     exit({failed_starting_handler, Reason})
             end;
+        {error, timeout} ->
+            i("timeout"),
+            acceptor_loop(A);
         {error, Reason} ->
             e("accept failure: "
               "~n   ~p", [Reason]),