[snmp|manager] Use of inet-backend for gen_udp

Make it possible to configure manager transport (net-if) to
use the inet_backend gen_udp option.

OTP-17526

1 files changed, 87 insertions, 52 deletions

diff --git a/lib/snmp/src/manager/snmpm_net_if.erl b/lib/snmp/src/manager/snmpm_net_if.erl
index 1eb5ae216a..5ff8f91a6e 100644
--- a/lib/snmp/src/manager/snmpm_net_if.erl
+++ b/lib/snmp/src/manager/snmpm_net_if.erl
@@ -1,7 +1,7 @@
 %% 
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2004-2020. All Rights Reserved.
+%% Copyright Ericsson AB 2004-2021. 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.
@@ -81,7 +81,11 @@
 
 -record(transport,
 	{socket,
-	 domain = snmpUDPDomain}).
+         port_info,
+         opts,
+	 domain       = snmpUDPDomain,
+         inet_backend = []
+        }).
 
 -define(DEFAULT_FILTER_MODULE, snmpm_net_if_filter).
 -define(DEFAULT_FILTER_OPTS,   [{module, ?DEFAULT_FILTER_MODULE}]).
@@ -285,15 +289,29 @@ do_init(Server, NoteStore) ->
     ?vdebug("Log: ~w", [Log]),
 
     {ok, DomainAddresses} = snmpm_config:system_info(transports),
-    ?vdebug("DomainAddresses: ~w",[DomainAddresses]),
+    ?vdebug("DomainAddresses: ~w", [DomainAddresses]),
     CommonSocketOpts = common_socket_opts(Opts),
-    BindTo = get_opt(Opts, bind_to,  false),
+    BindTo = get_opt(Opts, bind_to, false),
+    InetBackend = case get_opt(Opts, inet_backend, use_default) of
+                      use_default -> [];
+                      IB          -> [{inet_backend, IB}]
+                  end,
     case
 	[begin
 	     {IpPort, SocketOpts} =
 		 socket_params(Domain, Address, BindTo, CommonSocketOpts),
-	     Socket = socket_open(IpPort, SocketOpts),
-	     #transport{socket = Socket, domain = Domain}
+             %% The 'inet-backend' option has to be first,
+             %% so we might as well add it last.
+	     Socket = socket_open(IpPort, InetBackend ++ SocketOpts),
+             ?vtrace("socket created: "
+                     "~n      Ip Port:     ~p"
+                     "~n      Socket Opts: ~p"
+                     "~n      Socket:      ~p", [IpPort, SocketOpts, Socket]),
+	     #transport{socket       = Socket,
+                        port_info    = IpPort,
+                        opts         = SocketOpts,
+                        inet_backend = InetBackend,
+                        domain       = Domain}
 	 end || {Domain, Address} <- DomainAddresses]
     of
 	[] ->
@@ -318,9 +336,9 @@ do_init(Server, NoteStore) ->
     end.
 
 socket_open(IpPort, SocketOpts) ->
-    ?vtrace("socket_open -> entry with~n"
-	    "   IpPort:     ~p~n"
-	    "   SocketOpts: ~p", [IpPort, SocketOpts]),
+    ?vtrace("socket_open -> entry with"
+	    "~n      IpPort:     ~p"
+	    "~n      SocketOpts: ~p", [IpPort, SocketOpts]),
     case gen_udp:open(IpPort, SocketOpts) of
 	{error, _} = Error ->
 	    throw(Error);
@@ -354,6 +372,7 @@ socket_params(Domain, {IpAddr, IpPort} = Addr, BindTo, CommonSocketOpts) ->
 	_ ->
 	    socket_params(SocketOpts, Addr, BindTo)
     end.
+
 %%
 socket_params(SocketOpts, {IpAddr, IpPort}, BindTo) ->
     case BindTo of
@@ -1253,9 +1272,9 @@ error_msg(F, A) ->
 
 %%%-------------------------------------------------------------------
 
-% get_opt(Key, Opts) ->
-%     ?vtrace("get option ~w", [Key]),
-%     snmp_misc:get_option(Key, Opts).
+%% get_opt(Key, Opts) ->
+%%     ?vtrace("get option ~w", [Key]),
+%%     snmp_misc:get_option(Key, Opts).
 
 get_opt(Opts, Key, Def) ->
     ?vtrace("get option ~w with default ~p", [Key, Def]),
@@ -1265,10 +1284,19 @@ get_opt(Opts, Key, Def) ->
 %% -------------------------------------------------------------------
 
 get_info(#state{transports = Transports}) ->
-    ProcSize = proc_mem(self()),
-    [{process_memory, ProcSize}
-     | [{port_info, get_port_info(Socket)}
-	|| #transport{socket = Socket} <- Transports]].
+    ProcSize      = proc_mem(self()),
+    Counters      = get_counters(),
+    TransportInfo = [#{tdomain     => Domain,
+                       port_info   => PI,
+                       opts        => Opts,
+                       socket_info => get_socket_info(Socket)} ||
+                        #transport{socket    = Socket,
+                                   port_info = PI,
+                                   opts      = Opts,
+                                   domain    = Domain} <- Transports],
+    [{counters,       Counters},
+     {process_memory, ProcSize},
+     {transport_info, TransportInfo}].
 
 proc_mem(P) when is_pid(P) ->
     case (catch erlang:process_info(P, memory)) of
@@ -1279,35 +1307,9 @@ proc_mem(P) when is_pid(P) ->
     end.
 
 
-get_port_info(Id) ->
-    PortInfo = 
-	case (catch erlang:port_info(Id)) of
-	    PI when is_list(PI) ->
-		[{port_info, PI}];
-	    _ ->
-		[]
-	end,
-    PortStatus = 
-	case (catch prim_inet:getstatus(Id)) of
-	    {ok, PS} ->
-		[{port_status, PS}];
-	    _ ->
-		[]
-	end,
-    PortAct = 
-	case (catch inet:getopts(Id, [active])) of
-	    {ok, PA} ->
-		[{port_act, PA}];
-	    _ ->
-		[]
-	end,
-    PortStats = 
-	case (catch inet:getstat(Id)) of
-	    {ok, Stat} ->
-		[{port_stats, Stat}];
-	    _ ->
-		[]
-	end,
+get_socket_info(Id) when is_port(Id) ->
+    Info = inet:info(Id),
+
     IfList = 
 	case (catch inet:getif(Id)) of
 	    {ok, IFs} ->
@@ -1315,6 +1317,29 @@ get_port_info(Id) ->
 	    _ ->
 		[]
 	end,
+
+    BufSz = 
+	case (catch inet:getopts(Id, [recbuf, sndbuf, buffer])) of
+	    {ok, Sz} ->
+		[{buffer_size, Sz}];
+	    _ ->
+		[]
+	end,
+
+    [{socket, Id}, {info, Info}] ++ IfList ++ BufSz;
+
+get_socket_info(Id) ->
+    Info = inet:info(Id),
+
+    %% Does not exist for 'socket' ... yet
+    %% IfList = 
+    %%     case (catch inet:getif(Id)) of
+    %%         {ok, IFs} ->
+    %%     	[{interfaces, IFs}];
+    %%         _ ->
+    %%     	[]
+    %%     end,
+
     BufSz = 
 	case (catch inet:getopts(Id, [recbuf, sndbuf, buffer])) of
 	    {ok, Sz} ->
@@ -1322,13 +1347,9 @@ get_port_info(Id) ->
 	    _ ->
 		[]
 	end,
-    [{socket, Id}] ++ 
-	IfList ++ 
-	PortStats ++ 
-	PortInfo ++ 
-	PortStatus ++ 
-	PortAct ++
-	BufSz.
+
+    [{socket, Id}, {info, Info}] ++ BufSz.
+
 
 
 %%-----------------------------------------------------------------
@@ -1356,6 +1377,20 @@ counters() ->
 inc(Name)    -> inc(Name, 1).
 inc(Name, N) -> snmpm_config:incr_stats_counter(Name, N).
 
+get_counters() ->
+    Counters = counters(),
+    get_counters(Counters, []).
+
+get_counters([], Acc) ->
+    lists:reverse(Acc);
+get_counters([Counter|Counters], Acc) ->
+    case snmpm_config:get_stats_counter(Counter) of
+	{ok, CounterVal} ->
+	    get_counters(Counters, [{Counter, CounterVal}|Acc]);
+	_ ->
+	    get_counters(Counters, Acc)
+    end.
+
 
 %% ----------------------------------------------------------------