%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1999-2016. 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.
%% You may obtain a copy of the License at
%%
%% http://www.apache.org/licenses/LICENSE-2.0
%%
%% Unless required by applicable law or agreed to in writing, software
%% distributed under the License is distributed on an "AS IS" BASIS,
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%% See the License for the specific language governing permissions and
%% limitations under the License.
%%
%% %CopyrightEnd%
%%
%%
%%-----------------------------------------------------------------
%%
%% Description:
%% This file handles the H.248 UDP connections.
%%
%%-----------------------------------------------------------------
-module(megaco_udp_server).
-behaviour(gen_server).
%%-----------------------------------------------------------------
%% Include files
%%-----------------------------------------------------------------
-include_lib("megaco/src/udp/megaco_udp.hrl").
-include_lib("megaco/src/app/megaco_internal.hrl").
%%-----------------------------------------------------------------
%% External exports
%%-----------------------------------------------------------------
-export([
start_link/1,
stop/1,
upgrade_receive_handle/2
]).
%%-----------------------------------------------------------------
%% Internal exports
%%-----------------------------------------------------------------
-export([
init/1,
handle_call/3,
handle_cast/2,
handle_info/2,
code_change/3,
terminate/2,
handle_received_message/5
]).
%%-----------------------------------------------------------------
%% External interface functions
%%-----------------------------------------------------------------
%%-----------------------------------------------------------------
%% Func: start_link/1
%% Description: Starts the process that keeps track of an UDP
%% socket.
%%-----------------------------------------------------------------
start_link(Arg) ->
gen_server:start_link(?MODULE, Arg, []).
%%-----------------------------------------------------------------
%% Func: stop/1
%% Description: Stops the process that keeps track of an UDP
%% socket.
%%-----------------------------------------------------------------
stop(Pid) ->
call(Pid, stop).
upgrade_receive_handle(Pid, NewHandle) ->
call(Pid, {upgrade_receive_handle, NewHandle}).
%%-----------------------------------------------------------------
%% Internal interface functions
%%-----------------------------------------------------------------
%%-----------------------------------------------------------------
%% Server functions
%%-----------------------------------------------------------------
%%-----------------------------------------------------------------
%% Func: init/1
%% Description: Init funcion for the generic server
%%-----------------------------------------------------------------
init(Arg) ->
?udp_debug(Arg, "udp server starting", [self()]),
{ok, Arg}.
%%-----------------------------------------------------------------
%% Func: terminate/2
%% Description: Termination function for the generic server
%%-----------------------------------------------------------------
terminate(Reason, State) ->
?udp_debug(State, "udp server terminating", [self(), Reason]),
ok.
%%-----------------------------------------------------------------
%% Func: handle_call/3
%% Description: Handling call messages (really just stop and garbage)
%%-----------------------------------------------------------------
handle_call(stop, _From, UdpRec) ->
Reply = do_stop(UdpRec),
{stop, shutdown, Reply, UdpRec};
handle_call({upgrade_receive_handle, NewHandle}, _From, UdpRec) ->
{reply, ok, UdpRec#megaco_udp{receive_handle = NewHandle}};
handle_call(Req, From, UdpRec) ->
warning_msg("received unexpected request from ~p: "
"~n~p", [From, Req]),
{reply, {error, {invalid_request, Req}}, UdpRec}.
%%-----------------------------------------------------------------
%% Func: handle_cast/2
%% Description: Handling cast messages (really just stop and garbage)
%%-----------------------------------------------------------------
handle_cast(stop, UdpRec) ->
do_stop(UdpRec),
{stop, shutdown, UdpRec};
handle_cast(Msg, UdpRec) ->
warning_msg("received unexpected message: "
"~n~w", [Msg]),
{noreply, UdpRec}.
%%-----------------------------------------------------------------
%% Func: handle_info/2
%% Description: Handling non call/cast messages. Incomming messages
%% from the socket and exit codes.
%%-----------------------------------------------------------------
handle_info({udp, _UdpId, Ip, Port, Msg},
#megaco_udp{serialize = false} = UdpRec) ->
#megaco_udp{socket = Socket, module = Mod, receive_handle = RH} = UdpRec,
SH = megaco_udp:create_send_handle(Socket, Ip, Port),
MsgSize = size(Msg),
incNumInMessages(SH),
incNumInOctets(SH, MsgSize),
case MsgSize of
Sz when Sz < ?GC_MSG_LIMIT ->
apply(Mod, receive_message, [RH, self(), SH, Msg]);
Sz ->
receive_message(Mod, RH, SH, Sz, Msg)
end,
inet:setopts(Socket, [{active, once}]),
{noreply, UdpRec};
handle_info({udp, _UdpId, Ip, Port, Msg},
#megaco_udp{serialize = true} = UdpRec) ->
#megaco_udp{socket = Socket, module = Mod, receive_handle = RH} = UdpRec,
SH = megaco_udp:create_send_handle(Socket, Ip, Port),
MsgSize = size(Msg),
incNumInMessages(SH),
incNumInOctets(SH, MsgSize),
process_received_message(Mod, RH, SH, Msg),
inet:setopts(Socket, [{active, once}]),
{noreply, UdpRec};
handle_info(Info, UdpRec) ->
warning_msg("received unexpected info: "
"~n~w", [Info]),
{noreply, UdpRec}.
process_received_message(Mod, RH, SH, Msg) ->
case (catch Mod:process_received_message(RH, self(), SH, Msg)) of
ok ->
ok;
Error ->
error_msg("failed processing received message: "
"~n~p", [Error]),
ok
end.
receive_message(Mod, RH, SendHandle, Length, Msg) ->
Opts = [link , {min_heap_size, ?HEAP_SIZE(Length)}],
spawn_opt(?MODULE, handle_received_message,
[Mod, RH, self(), SendHandle, Msg], Opts).
handle_received_message(Mod, RH, Parent, SH, Msg) ->
Mod:process_received_message(RH, Parent, SH, Msg),
unlink(Parent),
exit(normal).
%%-----------------------------------------------------------------
%% Func: code_change/3
%% Descrition: Handles code change messages during upgrade.
%%-----------------------------------------------------------------
code_change(_Vsn, State, _Extra) ->
{ok, State}.
do_stop(#megaco_udp{socket = Socket}) ->
gen_udp:close(Socket).
%%-----------------------------------------------------------------
%% Func: incNumInMessages/1, incNumInOctets/2, incNumErrors/1
%% Description: SNMP counter increment functions
%%
%%-----------------------------------------------------------------
incNumInMessages(SH) ->
incCounter({SH, medGwyGatewayNumInMessages}, 1).
incNumInOctets(SH, NumOctets) ->
incCounter({SH, medGwyGatewayNumInOctets}, NumOctets).
incCounter(Key, Inc) ->
ets:update_counter(megaco_udp_stats, Key, Inc).
% incNumErrors(SH) ->
% incCounter({SH, medGwyGatewayNumErrors}, 1).
%% info_msg(F, A) ->
%% ?megaco_info("UDP server: " ++ F, A).
warning_msg(F, A) ->
?megaco_warning("UDP server: " ++ F, A).
error_msg(F, A) ->
?megaco_error("UDP server: " ++ F, A).
call(Pid, Req) ->
gen_server:call(Pid, Req, infinity).
