src/lwes_channel_manager.erl

   1 -module (lwes_channel_manager).
   2
   3 -behaviour (gen_server).
   4
   5 -include_lib ("lwes.hrl").
   6 -include_lib ("lwes_internal.hrl").
   7
   8 %% API
   9 -export ([ start_link/0,
  10            open_channel/1,
  11            register_channel/2,
  12            unregister_channel/1,
  13            find_channel/1,
  14            close_channel/1
  15          ]).
  16
  17 %% gen_server callbacks
  18 -export ([ init/1,
  19            handle_call/3,
  20            handle_cast/2,
  21            handle_info/2,
  22            terminate/2,
  23            code_change/3
  24          ]).
  25
  26 -define (TABLE, lwes_channels).
  27 -record (state, {}).
  28
  29 %%====================================================================
  30 %% API
  31 %%====================================================================
  32 start_link () ->
  33   gen_server:start_link ( { local, ?MODULE }, ?MODULE, [], []).
  34
  35 open_channel (Channel) ->
  36   lwes_channel_sup:open_channel (Channel).
  37
  38 register_channel (Channel, Pid) ->
  39   gen_server:call (?MODULE, {reg, Channel, Pid}).
  40
  41 unregister_channel (Channel) ->
  42   gen_server:call (?MODULE, {unreg, Channel}).
  43
  44 find_channel (Channel) ->
  45   case ets:lookup (?TABLE, Channel) of
  46     [] -> {error, not_open} ;
  47     [{_Channel, Pid}] -> Pid
  48   end.
  49
  50 close_channel (Channel) ->
  51   gen_server:call (find_channel (Channel), stop).
  52
  53 %%====================================================================
  54 %% gen_server callbacks
  55 %%====================================================================
  56 init ([]) ->
  57   ets:new (?TABLE, [ named_table, { read_concurrency, true } ]),
  58   { ok, #state {} }.
  59
  60 handle_call ({reg, Key, Val}, _From, State) ->
  61   { reply, ets:insert (?TABLE, {Key, Val}), State };
  62 handle_call ({unreg, Key}, _From, State) ->
  63   {reply, ets:delete (?TABLE, Key), State };
  64 handle_call (Request, From, State) ->
  65   error_logger:warning_msg
  66     ("lwes_channel_manager unrecognized call ~p from ~p~n",[Request, From]),
  67   { reply, ok, State }.
  68
  69 handle_cast (Request, State) ->
  70   error_logger:warning_msg
  71     ("lwes_channel_manager unrecognized cast ~p~n",[Request]),
  72   { noreply, State }.
  73
  74 handle_info (Request, State) ->
  75   error_logger:warning_msg
  76     ("lwes_channel_manager unrecognized info ~p~n",[Request]),
  77   {noreply, State}.
  78
  79 terminate (_Reason, _State) ->
  80   ets:delete (?TABLE),
  81   ok.
  82
  83 code_change (_OldVsn, State, _Extra) ->
  84   {ok, State}.
  85
  86 %%====================================================================
  87 %% Internal functions
  88 %%====================================================================
  89
  90 %%====================================================================
  91 %% Test functions
  92 %%====================================================================
  93 -ifdef (TEST).
  94 -include_lib ("eunit/include/eunit.hrl").
  95
  96 -endif.