%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2010-2011. All Rights Reserved.
%%
%% The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
%% compliance with the License. You should have received a copy of the
%% Erlang Public License along with this software. If not, it can be
%% retrieved online at http://www.erlang.org/.
%%
%% Software distributed under the License is distributed on an "AS IS"
%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
%% the License for the specific language governing rights and limitations
%% under the License.
%%
%% %CopyrightEnd%
%%
-module(diameter_peer).
-behaviour(gen_server).
%% Interface towards transport modules ...
-export([recv/2,
up/1,
up/2]).
%% ... and the stack.
-export([start/1,
send/2,
close/1,
abort/1,
notify/2]).
%% Old interface only called from old code.
-export([start/3]). %% < diameter-1.2 (R15B02)
%% Server start.
-export([start_link/0]).
%% gen_server callbacks
-export([init/1,
terminate/2,
handle_call/3,
handle_cast/2,
handle_info/2,
code_change/3]).
%% debug
-export([state/0,
uptime/0]).
-include_lib("diameter/include/diameter.hrl").
-include("diameter_internal.hrl").
%% Registered name of the server.
-define(SERVER, ?MODULE).
%% Server state.
-record(state, {id = now()}).
%% Default transport_module/config.
-define(DEFAULT_TMOD, diameter_tcp).
-define(DEFAULT_TCFG, []).
-define(DEFAULT_TTMO, infinity).
%%% ---------------------------------------------------------------------------
%%% # notify/2
%%% ---------------------------------------------------------------------------
notify(SvcName, T) ->
rpc:abcast(nodes(), ?SERVER, {notify, SvcName, T}).
%%% ---------------------------------------------------------------------------
%%% # start/3
%%% ---------------------------------------------------------------------------
%% From old code: make is restart.
start(_T, _Opts, #diameter_service{}) ->
{error, restart}.
%%% ---------------------------------------------------------------------------
%%% # start/1
%%% ---------------------------------------------------------------------------
-spec start({T, [Opt], #diameter_service{}})
-> {TPid, [Addr], Tmo, Data}
| {error, [term()]}
when T :: {connect|accept, diameter:transport_ref()},
Opt :: diameter:transport_opt(),
TPid :: pid(),
Addr :: inet:ip_address(),
Tmo :: non_neg_integer(),
Data :: {{T, Mod, Cfg}, [Mod], [{T, [Mod], Cfg}], [Err]},
Mod :: module(),
Cfg :: term(),
Err :: term().
%% Initial start.
start({T, Opts, #diameter_service{} = Svc}) ->
start(T, Svc, pair(Opts, [], []), []);
%% Subsequent start.
start({#diameter_service{} = Svc, Tmo, {{T, _, Cfg}, Ms, Rest, Errs}}) ->
start(T, Ms, Cfg, Svc, Tmo, Rest, Errs).
%% pair/3
%%
%% Pair transport modules with config.
%% Another transport_module: accumulate it.
pair([{transport_module, M} | Rest], Mods, Acc) ->
pair(Rest, [M|Mods], Acc);
%% Another transport_config: accumulate another tuple.
pair([{transport_config = T, C} | Rest], Mods, Acc) ->
pair([{T, C, ?DEFAULT_TTMO} | Rest], Mods, Acc);
pair([{transport_config, C, Tmo} | Rest], Mods, Acc) ->
pair(Rest, [], acc({Mods, C, Tmo}, Acc));
pair([_ | Rest], Mods, Acc) ->
pair(Rest, Mods, Acc);
%% No transport_module or transport_config: defaults.
pair([], [], []) ->
[{[?DEFAULT_TMOD], ?DEFAULT_TCFG, ?DEFAULT_TTMO}];
%% One transport_module, one transport_config.
pair([], [M], [{[], Cfg, Tmo}]) ->
[{[M], Cfg, Tmo}];
%% Trailing transport_module: default transport_config.
pair([], [_|_] = Mods, Acc) ->
lists:reverse(acc({Mods, ?DEFAULT_TCFG, ?DEFAULT_TTMO}, Acc));
pair([], [], Acc) ->
lists:reverse(def(Acc)).
%% acc/2
acc(T, Acc) ->
[T | def(Acc)].
%% def/1
%%
%% Default module of previous pair if none were specified.
def([{[], Cfg, Tmo} | Acc]) ->
[{[?DEFAULT_TMOD], Cfg, Tmo} | Acc];
def(Acc) ->
Acc.
%% start/4
start(T, Svc, [{Ms, Cfg, Tmo} | Rest], Errs) ->
start(T, Ms, Cfg, Svc, Tmo, Rest, Errs);
start(_, _, [], Errs) ->
{error, Errs}.
%% start/7
start(T, [], _, Svc, _, Rest, Errs) ->
start(T, Svc, Rest, Errs);
start(T, [M|Ms], Cfg, Svc, Tmo, Rest, Errs) ->
case start(M, [T, Svc, Cfg]) of
{ok, TPid} ->
{TPid, [], Tmo, {{T, M, Cfg}, Ms, Rest, Errs}};
{ok, TPid, [_|_] = Addrs} ->
{TPid, Addrs, Tmo, {{T, M, Cfg}, Ms, Rest, Errs}};
E ->
start(T, Ms, Cfg, Svc, Tmo, Rest, [E|Errs])
end.
%% start/2
start(Mod, Args) ->
apply(Mod, start, Args).
%%% ---------------------------------------------------------------------------
%%% # up/[12]
%%% ---------------------------------------------------------------------------
up(Pid) -> %% accepting transport
ifc_send(Pid, {self(), connected}).
up(Pid, Remote) -> %% connecting transport
ifc_send(Pid, {self(), connected, Remote}).
%%% ---------------------------------------------------------------------------
%%% # recv/2
%%% ---------------------------------------------------------------------------
recv(Pid, Pkt) ->
ifc_send(Pid, {recv, Pkt}).
%%% ---------------------------------------------------------------------------
%%% # send/2
%%% ---------------------------------------------------------------------------
send(Pid, #diameter_packet{transport_data = undefined,
bin = Bin}) ->
send(Pid, Bin);
send(Pid, Pkt) ->
ifc_send(Pid, {send, Pkt}).
%%% ---------------------------------------------------------------------------
%%% # close/1
%%% ---------------------------------------------------------------------------
close(Pid) ->
ifc_send(Pid, {close, self()}).
%%% ---------------------------------------------------------------------------
%%% # abort/1
%%% ---------------------------------------------------------------------------
abort(Pid) ->
exit(Pid, shutdown).
%% ---------------------------------------------------------------------------
%% ---------------------------------------------------------------------------
start_link() ->
ServerName = {local, ?SERVER},
Module = ?MODULE,
Args = [],
Options = [{spawn_opt, diameter_lib:spawn_opts(server, [])}],
gen_server:start_link(ServerName, Module, Args, Options).
state() ->
call(state).
uptime() ->
call(uptime).
%%% ----------------------------------------------------------
%%% # init(Role)
%%% ----------------------------------------------------------
init([]) ->
{ok, #state{}}.
%%% ----------------------------------------------------------
%%% # handle_call(Request, From, State)
%%% ----------------------------------------------------------
handle_call(state, _, State) ->
{reply, State, State};
handle_call(uptime, _, #state{id = Time} = State) ->
{reply, diameter_lib:now_diff(Time), State};
handle_call(Req, From, State) ->
?UNEXPECTED([Req, From]),
{reply, nok, State}.
%%% ----------------------------------------------------------
%%% # handle_cast(Request, State)
%%% ----------------------------------------------------------
handle_cast(Msg, State) ->
?UNEXPECTED([Msg]),
{noreply, State}.
%%% ----------------------------------------------------------
%%% # handle_info(Request, State)
%%% ----------------------------------------------------------
%% Remote service is distributing a message.
handle_info({notify, SvcName, T}, S) ->
bang(diameter_service:whois(SvcName), T),
{noreply, S};
handle_info(Info, State) ->
?UNEXPECTED([Info]),
{noreply, State}.
%% ----------------------------------------------------------
%% terminate(Reason, State)
%% ----------------------------------------------------------
terminate(_Reason, _State) ->
ok.
%% ----------------------------------------------------------
%% code_change(OldVsn, State, Extra)
%% ----------------------------------------------------------
code_change(_OldVsn, State, _Extra) ->
{ok, State}.
%% ---------------------------------------------------------
%% INTERNAL FUNCTIONS
%% ---------------------------------------------------------
%% ifc_send/2
%%
%% Send something over the transport interface.
ifc_send(Pid, T) ->
Pid ! {diameter, T}.
%% bang/2
bang(undefined = No, _) ->
No;
bang(Pid, T) ->
Pid ! T.
%% call/1
call(Request) ->
gen_server:call(?SERVER, Request, infinity).
