Move rabbit_net:accept_ack() to rabbit_networking

... in rabbitmq-server.

This resolves a reverse dependency of rabbitmq-common on
rabbitmq-server. However, this breaks the API because we can't keep a
compatibility function.

[#118490793]

Author: dumbbell

src/rabbit_networking.erl

@@ -34,7 +34,8 @@
          connections/0, connection_info_keys/0,
          connection_info/1, connection_info/2,
          connection_info_all/0, connection_info_all/1, connection_info_all/3,
-         close_connection/2, force_connection_event_refresh/1, tcp_host/1]).
+         close_connection/2, force_connection_event_refresh/1, accept_ack/2,
+         tcp_host/1]).
 
 %% Used by TCP-based transports, e.g. STOMP adapter
 -export([tcp_listener_addresses/1, tcp_listener_spec/9,
@@ -87,6 +88,7 @@
           'ok'.
 -spec close_connection(pid(), string()) -> 'ok'.
 -spec force_connection_event_refresh(reference()) -> 'ok'.
+-spec accept_ack(any(), rabbit_net:socket()) -> ok.
 
 -spec on_node_down(node()) -> 'ok'.
 -spec tcp_listener_addresses(listener_config()) -> [address()].
@@ -313,6 +315,22 @@ force_connection_event_refresh(Ref) ->
     [rabbit_reader:force_event_refresh(C, Ref) || C <- connections()],
     ok.
 
+accept_ack(Ref, Sock) ->
+    ok = ranch:accept_ack(Ref),
+    case tune_buffer_size(Sock) of
+        ok         -> ok;
+        {error, _} -> rabbit_net:fast_close(Sock),
+                      exit(normal)
+    end,
+    ok = file_handle_cache:obtain().
+
+tune_buffer_size(Sock) ->
+    case rabbit_net:getopts(Sock, [sndbuf, recbuf, buffer]) of
+        {ok, BufSizes} -> BufSz = lists:max([Sz || {_Opt, Sz} <- BufSizes]),
+                          rabbit_net:setopts(Sock, [{buffer, BufSz}]);
+        Error          -> Error
+    end.
+
 %%--------------------------------------------------------------------
 
 tcp_host(IPAddress) ->

src/rabbit_reader.erl

@@ -231,7 +231,7 @@ shutdown(Pid, Explanation) ->
     gen_server:call(Pid, {shutdown, Explanation}, infinity).
 
 init(Parent, HelperSup, Ref, Sock) ->
-    rabbit_net:accept_ack(Ref, Sock),
+    rabbit_networking:accept_ack(Ref, Sock),
     Deb = sys:debug_options([]),
     start_connection(Parent, HelperSup, Deb, Sock).