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Diffstat (limited to 'deps/ibrowse/src/ibrowse_lb.erl')
| -rw-r--r-- | deps/ibrowse/src/ibrowse_lb.erl | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/deps/ibrowse/src/ibrowse_lb.erl b/deps/ibrowse/src/ibrowse_lb.erl new file mode 100644 index 00000000..0e001d48 --- /dev/null +++ b/deps/ibrowse/src/ibrowse_lb.erl @@ -0,0 +1,235 @@ +%%%------------------------------------------------------------------- +%%% File : ibrowse_lb.erl +%%% Author : chandru <chandrashekhar.mullaparthi@t-mobile.co.uk> +%%% Description : +%%% +%%% Created : 6 Mar 2008 by chandru <chandrashekhar.mullaparthi@t-mobile.co.uk> +%%%------------------------------------------------------------------- +-module(ibrowse_lb). +-author(chandru). +-behaviour(gen_server). +%%-------------------------------------------------------------------- +%% Include files +%%-------------------------------------------------------------------- + +%%-------------------------------------------------------------------- +%% External exports +-export([ + start_link/1, + spawn_connection/5, + stop/1 + ]). + +%% gen_server callbacks +-export([ + init/1, + handle_call/3, + handle_cast/2, + handle_info/2, + terminate/2, + code_change/3 + ]). + +-record(state, {parent_pid, + ets_tid, + host, + port, + max_sessions, + max_pipeline_size, + num_cur_sessions = 0}). + +-include("ibrowse.hrl"). + +%%==================================================================== +%% External functions +%%==================================================================== +%%-------------------------------------------------------------------- +%% Function: start_link/0 +%% Description: Starts the server +%%-------------------------------------------------------------------- +start_link(Args) -> + gen_server:start_link(?MODULE, Args, []). + +%%==================================================================== +%% Server functions +%%==================================================================== + +%%-------------------------------------------------------------------- +%% Function: init/1 +%% Description: Initiates the server +%% Returns: {ok, State} | +%% {ok, State, Timeout} | +%% ignore | +%% {stop, Reason} +%%-------------------------------------------------------------------- +init([Host, Port]) -> + process_flag(trap_exit, true), + Max_sessions = ibrowse:get_config_value({max_sessions, Host, Port}, 10), + Max_pipe_sz = ibrowse:get_config_value({max_pipeline_size, Host, Port}, 10), + put(my_trace_flag, ibrowse_lib:get_trace_status(Host, Port)), + put(ibrowse_trace_token, ["LB: ", Host, $:, integer_to_list(Port)]), + Tid = ets:new(ibrowse_lb, [public, ordered_set]), + {ok, #state{parent_pid = whereis(ibrowse), + host = Host, + port = Port, + ets_tid = Tid, + max_pipeline_size = Max_pipe_sz, + max_sessions = Max_sessions}}. + +spawn_connection(Lb_pid, Url, + Max_sessions, + Max_pipeline_size, + SSL_options) + when is_pid(Lb_pid), + is_record(Url, url), + is_integer(Max_pipeline_size), + is_integer(Max_sessions) -> + gen_server:call(Lb_pid, + {spawn_connection, Url, Max_sessions, Max_pipeline_size, SSL_options}). + +stop(Lb_pid) -> + case catch gen_server:call(Lb_pid, stop) of + {'EXIT', {timeout, _}} -> + exit(Lb_pid, kill); + ok -> + ok + end. +%%-------------------------------------------------------------------- +%% Function: handle_call/3 +%% Description: Handling call messages +%% Returns: {reply, Reply, State} | +%% {reply, Reply, State, Timeout} | +%% {noreply, State} | +%% {noreply, State, Timeout} | +%% {stop, Reason, Reply, State} | (terminate/2 is called) +%% {stop, Reason, State} (terminate/2 is called) +%%-------------------------------------------------------------------- +% handle_call({spawn_connection, _Url, Max_sess, Max_pipe, _}, _From, +% #state{max_sessions = Max_sess, +% ets_tid = Tid, +% max_pipeline_size = Max_pipe_sz, +% num_cur_sessions = Num} = State) +% when Num >= Max -> +% Reply = find_best_connection(Tid), +% {reply, sorry_dude_reuse, State}; + +%% Update max_sessions in #state with supplied value +handle_call({spawn_connection, _Url, Max_sess, Max_pipe, _}, _From, + #state{num_cur_sessions = Num} = State) + when Num >= Max_sess -> + State_1 = maybe_create_ets(State), + Reply = find_best_connection(State_1#state.ets_tid, Max_pipe), + {reply, Reply, State_1#state{max_sessions = Max_sess}}; + +handle_call({spawn_connection, Url, _Max_sess, _Max_pipe, SSL_options}, _From, + #state{num_cur_sessions = Cur} = State) -> + State_1 = maybe_create_ets(State), + Tid = State_1#state.ets_tid, + {ok, Pid} = ibrowse_http_client:start_link({Tid, Url, SSL_options}), + ets:insert(Tid, {{1, Pid}, []}), + {reply, {ok, Pid}, State_1#state{num_cur_sessions = Cur + 1}}; + +handle_call(stop, _From, #state{ets_tid = undefined} = State) -> + gen_server:reply(_From, ok), + {stop, normal, State}; + +handle_call(stop, _From, #state{ets_tid = Tid} = State) -> + ets:foldl(fun({{_, Pid}, _}, Acc) -> + ibrowse_http_client:stop(Pid), + Acc + end, [], Tid), + gen_server:reply(_From, ok), + {stop, normal, State}; + +handle_call(Request, _From, State) -> + Reply = {unknown_request, Request}, + {reply, Reply, State}. + +%%-------------------------------------------------------------------- +%% Function: handle_cast/2 +%% Description: Handling cast messages +%% Returns: {noreply, State} | +%% {noreply, State, Timeout} | +%% {stop, Reason, State} (terminate/2 is called) +%%-------------------------------------------------------------------- +handle_cast(_Msg, State) -> + {noreply, State}. + +%%-------------------------------------------------------------------- +%% Function: handle_info/2 +%% Description: Handling all non call/cast messages +%% Returns: {noreply, State} | +%% {noreply, State, Timeout} | +%% {stop, Reason, State} (terminate/2 is called) +%%-------------------------------------------------------------------- +handle_info({'EXIT', Parent, _Reason}, #state{parent_pid = Parent} = State) -> + {stop, normal, State}; + +handle_info({'EXIT', _Pid, _Reason}, #state{ets_tid = undefined} = State) -> + {noreply, State}; + +handle_info({'EXIT', Pid, _Reason}, + #state{num_cur_sessions = Cur, + ets_tid = Tid} = State) -> + ets:match_delete(Tid, {{'_', Pid}, '_'}), + Cur_1 = Cur - 1, + State_1 = case Cur_1 of + 0 -> + ets:delete(Tid), + State#state{ets_tid = undefined}; + _ -> + State + end, + {noreply, State_1#state{num_cur_sessions = Cur_1}}; + +handle_info({trace, Bool}, #state{ets_tid = undefined} = State) -> + put(my_trace_flag, Bool), + {noreply, State}; + +handle_info({trace, Bool}, #state{ets_tid = Tid} = State) -> + ets:foldl(fun({{_, Pid}, _}, Acc) when is_pid(Pid) -> + catch Pid ! {trace, Bool}, + Acc; + (_, Acc) -> + Acc + end, undefined, Tid), + put(my_trace_flag, Bool), + {noreply, State}; + +handle_info(_Info, State) -> + {noreply, State}. + +%%-------------------------------------------------------------------- +%% Function: terminate/2 +%% Description: Shutdown the server +%% Returns: any (ignored by gen_server) +%%-------------------------------------------------------------------- +terminate(_Reason, _State) -> + ok. + +%%-------------------------------------------------------------------- +%% Func: code_change/3 +%% Purpose: Convert process state when code is changed +%% Returns: {ok, NewState} +%%-------------------------------------------------------------------- +code_change(_OldVsn, State, _Extra) -> + {ok, State}. + +%%-------------------------------------------------------------------- +%%% Internal functions +%%-------------------------------------------------------------------- +find_best_connection(Tid, Max_pipe) -> + case ets:first(Tid) of + {Cur_sz, Pid} when Cur_sz < Max_pipe -> + ets:delete(Tid, {Cur_sz, Pid}), + ets:insert(Tid, {{Cur_sz + 1, Pid}, []}), + {ok, Pid}; + _ -> + {error, retry_later} + end. + +maybe_create_ets(#state{ets_tid = undefined} = State) -> + Tid = ets:new(ibrowse_lb, [public, ordered_set]), + State#state{ets_tid = Tid}; +maybe_create_ets(State) -> + State. |