lib/etorrent-1.0/src/etorrent_t_control.erl

   1 %%%-------------------------------------------------------------------
   2 %%% File    : torrent.erl
   3 %%% Author  : Jesper Louis Andersen <jlouis@succubus.local.domain>
   4 %%% License : See COPYING
   5 %%% Description : Representation of a torrent for downloading
   6 %%%
   7 %%% Created :  9 Jul 2007 by Jesper Louis Andersen
   8 %%%   <jlouis@succubus.local.domain>
   9 %%%-------------------------------------------------------------------
  10 -module(etorrent_t_control).
  11
  12 -behaviour(gen_fsm).
  13
  14 -include("etorrent_piece.hrl").
  15
  16 %% API
  17 -export([start_link/3, start/1, stop/1,
  18         torrent_checked/2, tracker_error_report/2, seed/1,
  19         tracker_warning_report/2,
  20
  21         check_torrent/1]).
  22
  23 %% gen_fsm callbacks
  24 -export([init/1, handle_event/3, initializing/2, started/2,
  25          stopped/2, handle_sync_event/4, handle_info/3, terminate/3,
  26          code_change/4]).
  27
  28 -record(state, {id = none,
  29
  30                 path = none,
  31                 peer_id = none,
  32
  33                 parent_pid = none,
  34                 tracker_pid = none,
  35                 file_system_pid = none,
  36
  37                 disk_state = none,
  38                 available_peers = []}).
  39
  40 -define(CHECK_WAIT_TIME, 3000).
  41
  42 %%====================================================================
  43 %% API
  44 %%====================================================================
  45 %%--------------------------------------------------------------------
  46 %% Function: start_link() -> ok,Pid} | ignore | {error,Error}
  47 %% Description:Creates a gen_fsm process which calls Module:init/1 to
  48 %% initialize. To ensure a synchronized start-up procedure, this function
  49 %% does not return until Module:init/1 has returned.
  50 %%--------------------------------------------------------------------
  51 start_link(Id, Path, PeerId) ->
  52     gen_fsm:start_link(?MODULE, [self(), Id, Path, PeerId], []).
  53
  54 stop(Pid) ->
  55     gen_fsm:send_event(Pid, stop).
  56
  57 start(Pid) ->
  58     gen_fsm:send_event(Pid, start).
  59
  60 check_torrent(Pid) ->
  61     gen_fsm:send_event(Pid, check_torrent).
  62
  63 torrent_checked(Pid, DiskState) ->
  64     gen_fsm:send_event(Pid, {torrent_checked, DiskState}).
  65
  66 tracker_error_report(Pid, Report) ->
  67     gen_fsm:send_event(Pid, {tracker_error_report, Report}).
  68
  69 tracker_warning_report(Pid, Report) ->
  70     gen_fsm:send_event(Pid, {tracker_warning_report, Report}).
  71
  72 seed(Pid) ->
  73     gen_fsm:send_event(Pid, seed).
  74
  75 %%====================================================================
  76 %% gen_fsm callbacks
  77 %%====================================================================
  78 %%--------------------------------------------------------------------
  79 %% Function: init(Args) -> {ok, StateName, State} |
  80 %%                         {ok, StateName, State, Timeout} |
  81 %%                         ignore                              |
  82 %%                         {stop, StopReason}
  83 %% Description:Whenever a gen_fsm is started using gen_fsm:start/[3,4] or
  84 %% gen_fsm:start_link/3,4, this function is called by the new process to
  85 %% initialize.
  86 %%--------------------------------------------------------------------
  87 init([Parent, Id, Path, PeerId]) ->
  88     process_flag(trap_exit, true),
  89     etorrent_tracking_map:new(Path, Parent, Id),
  90     {ok, initializing, #state{id = Id,
  91                               path = Path,
  92                               peer_id = PeerId,
  93                               parent_pid = Parent}, 0}. % Force timeout instantly.
  94
  95 %%--------------------------------------------------------------------
  96 %% Function:
  97 %% state_name(Event, State) -> {next_state, NextStateName, NextState}|
  98 %%                             {next_state, NextStateName,
  99 %%                                NextState, Timeout} |
 100 %%                             {stop, Reason, NewState}
 101 %% Description:There should be one instance of this function for each possible
 102 %% state name. Whenever a gen_fsm receives an event sent using
 103 %% gen_fsm:send_event/2, the instance of this function with the same name as
 104 %% the current state name StateName is called to handle the event. It is also
 105 %% called if a timeout occurs.
 106 %%--------------------------------------------------------------------
 107 % Load a torrent at Path with Torrent
 108 initializing(timeout, S) ->
 109     case etorrent_tracking_map:is_ready_for_checking(S#state.id) of
 110         false ->
 111             {next_state, initializing, S, ?CHECK_WAIT_TIME};
 112         true ->
 113             %% TODO: Try to coalesce some of these operations together.
 114
 115             %% Read the torrent, check its contents for what we are missing
 116             etorrent_event_mgr:checking_torrent(S#state.id),
 117             {ok, Torrent, FSPid, InfoHash, NumberOfPieces} =
 118                 etorrent_fs_checker:read_and_check_torrent(
 119                   S#state.id,
 120                   S#state.parent_pid,
 121                   S#state.path),
 122             %% Update the tracking map. This torrent has been started, and we
 123             %%  know its infohash
 124             etorrent_tracking_map:statechange(S#state.id, {infohash, InfoHash}),
 125             etorrent_tracking_map:statechange(S#state.id, started),
 126
 127             %% Add a torrent entry for this torrent.
 128             ok = etorrent_torrent:new(
 129                    S#state.id,
 130                    {{uploaded, 0},
 131                     {downloaded, 0},
 132                     {left, calculate_amount_left(S#state.id)},
 133                     {total, etorrent_metainfo:get_length(Torrent)}},
 134                    NumberOfPieces),
 135
 136             %% Start the tracker
 137             {ok, TrackerPid} =
 138                 etorrent_t_sup:add_tracker(
 139                   S#state.parent_pid,
 140                   etorrent_metainfo:get_url(Torrent),
 141                   etorrent_metainfo:get_infohash(Torrent),
 142                   S#state.peer_id,
 143                   S#state.id),
 144
 145             %% Since the process will now go to a hibernation state, GC it
 146             etorrent_event_mgr:started_torrent(S#state.id),
 147             garbage_collect(),
 148             {next_state, started,
 149              S#state{file_system_pid = FSPid,
 150                      tracker_pid = TrackerPid}}
 151
 152     end.
 153
 154 started(stop, S) ->
 155     {stop, argh, S};
 156 started(check_torrent, S) ->
 157     case etorrent_fs_checker:check_torrent(S#state.file_system_pid,
 158                                            S#state.id) of
 159         [] -> {next_state, started, S};
 160         Errors ->
 161             error_logger:info_report([errornous_pieces, {Errors}]),
 162             {next_state, started, S}
 163     end;
 164 started({tracker_error_report, Reason}, S) ->
 165     io:format("Got tracker error: ~s~n", [Reason]),
 166     {next_state, started, S}.
 167
 168 stopped(start, S) ->
 169     {stop, argh, S}.
 170
 171 %%--------------------------------------------------------------------
 172 %% Function:
 173 %% state_name(Event, From, State) -> {next_state, NextStateName, NextState} |
 174 %%                                   {next_state, NextStateName,
 175 %%                                     NextState, Timeout} |
 176 %%                                   {reply, Reply, NextStateName, NextState}|
 177 %%                                   {reply, Reply, NextStateName,
 178 %%                                    NextState, Timeout} |
 179 %%                                   {stop, Reason, NewState}|
 180 %%                                   {stop, Reason, Reply, NewState}
 181 %% Description: There should be one instance of this function for each
 182 %% possible state name. Whenever a gen_fsm receives an event sent using
 183 %% gen_fsm:sync_send_event/2,3, the instance of this function with the same
 184 %% name as the current state name StateName is called to handle the event.
 185 %%--------------------------------------------------------------------
 186
 187 %%--------------------------------------------------------------------
 188 %% Function:
 189 %% handle_event(Event, StateName, State) -> {next_state, NextStateName,
 190 %%                                                NextState} |
 191 %%                                          {next_state, NextStateName,
 192 %%                                                NextState, Timeout} |
 193 %%                                          {stop, Reason, NewState}
 194 %% Description: Whenever a gen_fsm receives an event sent using
 195 %% gen_fsm:send_all_state_event/2, this function is called to handle
 196 %% the event.
 197 %%--------------------------------------------------------------------
 198 handle_event(Msg, SN, S) ->
 199     io:format("Problem: ~p~n", [Msg]),
 200     {next_state, SN, S}.
 201
 202 %%--------------------------------------------------------------------
 203 %% Function:
 204 %% handle_sync_event(Event, From, StateName,
 205 %%                   State) -> {next_state, NextStateName, NextState} |
 206 %%                             {next_state, NextStateName, NextState,
 207 %%                              Timeout} |
 208 %%                             {reply, Reply, NextStateName, NextState}|
 209 %%                             {reply, Reply, NextStateName, NextState,
 210 %%                              Timeout} |
 211 %%                             {stop, Reason, NewState} |
 212 %%                             {stop, Reason, Reply, NewState}
 213 %% Description: Whenever a gen_fsm receives an event sent using
 214 %% gen_fsm:sync_send_all_state_event/2,3, this function is called to handle
 215 %% the event.
 216 %%--------------------------------------------------------------------
 217 handle_sync_event(_Event, _From, StateName, State) ->
 218     Reply = ok,
 219     {reply, Reply, StateName, State}.
 220
 221 %%--------------------------------------------------------------------
 222 %% Function:
 223 %% handle_info(Info,StateName,State)-> {next_state, NextStateName, NextState}|
 224 %%                                     {next_state, NextStateName, NextState,
 225 %%                                       Timeout} |
 226 %%                                     {stop, Reason, NewState}
 227 %% Description: This function is called by a gen_fsm when it receives any
 228 %% other message than a synchronous or asynchronous event
 229 %% (or a system message).
 230 %%--------------------------------------------------------------------
 231 handle_info(Info, StateName, State) ->
 232     error_logger:info_report([unknown_info, Info, StateName]),
 233     {next_state, StateName, State}.
 234
 235 %%--------------------------------------------------------------------
 236 %% Function: terminate(Reason, StateName, State) -> void()
 237 %% Description:This function is called by a gen_fsm when it is about
 238 %% to terminate. It should be the opposite of Module:init/1 and do any
 239 %% necessary cleaning up. When it returns, the gen_fsm terminates with
 240 %% Reason. The return value is ignored.
 241 %%--------------------------------------------------------------------
 242 terminate(_Reason, _StateName, S) ->
 243     ok = etorrent_piece_mgr:delete(S#state.id),
 244     etorrent_torrent:delete(S#state.id),
 245
 246     etorrent_tracking_map:delete(S#state.id),
 247     ok.
 248
 249 %%--------------------------------------------------------------------
 250 %% Function:
 251 %% code_change(OldVsn, StateName, State, Extra) -> {ok, StateName, NewState}
 252 %% Description: Convert process state when code is changed
 253 %%--------------------------------------------------------------------
 254 code_change(_OldVsn, StateName, State, _Extra) ->
 255     {ok, StateName, State}.
 256
 257 %%--------------------------------------------------------------------
 258 %%% Internal functions
 259 %%--------------------------------------------------------------------
 260 calculate_amount_left(Id) when is_integer(Id) ->
 261     Pieces = etorrent_piece_mgr:select(Id),
 262     lists:sum([size_piece(P) || P <- Pieces]).
 263
 264 size_piece(#piece{state = fetched}) -> 0;
 265 size_piece(#piece{state = not_fetched, files = Files}) ->
 266     lists:sum([Sz || {_F, _O, Sz} <- Files]).
 267
 268
 269