%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2008-2011. 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%
%%
%%
%% Description: User register for ssh_cli
-module(ssh_userreg).
-behaviour(gen_server).
%% API
-export([start_link/0,
register_user/2,
lookup_user/1,
delete_user/1]).
%% gen_server callbacks
-export([init/1,
handle_call/3,
handle_cast/2,
handle_info/2,
terminate/2,
code_change/3]).
-record(state, {user_db = []}).
%%====================================================================
%% API
%%====================================================================
%%--------------------------------------------------------------------
%% Function: start_link() -> {ok,Pid} | ignore | {error,Error}
%% Description: Starts the server
%%--------------------------------------------------------------------
start_link() ->
gen_server:start_link({local, ?MODULE}, ?MODULE, [], []).
register_user(User, Cm) ->
gen_server:cast(?MODULE, {register, {User, Cm}}).
delete_user(Cm) ->
gen_server:cast(?MODULE, {delete, Cm}).
lookup_user(Cm) ->
gen_server:call(?MODULE, {get_user, Cm}, infinity).
%%====================================================================
%% gen_server callbacks
%%====================================================================
%%--------------------------------------------------------------------
%% Function: init(Args) -> {ok, State} |
%% {ok, State, Timeout} |
%% ignore |
%% {stop, Reason}
%% Description: Initiates the server
%%--------------------------------------------------------------------
init([]) ->
{ok, #state{}}.
%%--------------------------------------------------------------------
%% Function: %% handle_call(Request, From, State) -> {reply, Reply, State} |
%% {reply, Reply, State, Timeout} |
%% {noreply, State} |
%% {noreply, State, Timeout} |
%% {stop, Reason, Reply, State} |
%% {stop, Reason, State}
%% Description: Handling call messages
%%--------------------------------------------------------------------
handle_call({get_user, Cm}, _From, #state{user_db = Db} = State) ->
User = lookup(Cm, Db),
{reply, {ok, User}, State}.
%%--------------------------------------------------------------------
%% Function: handle_cast(Msg, State) -> {noreply, State} |
%% {noreply, State, Timeout} |
%% {stop, Reason, State}
%% Description: Handling cast messages
%%--------------------------------------------------------------------
handle_cast({register, UserCm}, State) ->
{noreply, insert(UserCm, State)};
handle_cast({delete, UserCm}, State) ->
{noreply, delete(UserCm, State)}.
%%--------------------------------------------------------------------
%% Function: handle_info(Info, State) -> {noreply, State} |
%% {noreply, State, Timeout} |
%% {stop, Reason, State}
%% Description: Handling all non call/cast messages
%%--------------------------------------------------------------------
handle_info(_Info, State) ->
{noreply, State}.
%%--------------------------------------------------------------------
%% Function: terminate(Reason, State) -> void()
%% Description: This function is called by a gen_server when it is about to
%% terminate. It should be the opposite of Module:init/1 and do any necessary
%% cleaning up. When it returns, the gen_server terminates with Reason.
%% The return value is ignored.
%%--------------------------------------------------------------------
terminate(_Reason, _State) ->
ok.
%%--------------------------------------------------------------------
%% Func: code_change(OldVsn, State, Extra) -> {ok, NewState}
%% Description: Convert process state when code is changed
%%--------------------------------------------------------------------
code_change(_OldVsn, State, _Extra) ->
{ok, State}.
%%--------------------------------------------------------------------
%%% Internal functions
%%--------------------------------------------------------------------
insert({User, Cm}, #state{user_db = Db} = State) ->
State#state{user_db = [{User, Cm} | Db]}.
delete(Cm, #state{user_db = Db} = State) ->
State#state{user_db = lists:keydelete(Cm, 2, Db)}.
lookup(_, []) ->
undefined;
lookup(Cm, [{User, Cm} | _Rest]) ->
User;
lookup(Cm, [_ | Rest]) ->
lookup(Cm, Rest).