%% Copyright (c) 2011, Loïc Hoguin %% %% Permission to use, copy, modify, and/or distribute this software for any %% purpose with or without fee is hereby granted, provided that the above %% copyright notice and this permission notice appear in all copies. %% %% THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES %% WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF %% MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR %% ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES %% WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN %% ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF %% OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. %% @private -module(cowboy_acceptor). -export([start_link/6]). %% API. -export([acceptor/6]). %% Internal. %% API. -spec start_link(inet:socket(), module(), module(), any(), non_neg_integer(), pid()) -> {ok, pid()}. start_link(LSocket, Transport, Protocol, Opts, MaxConns, ReqsSup) -> Pid = spawn_link(?MODULE, acceptor, [LSocket, Transport, Protocol, Opts, MaxConns, ReqsSup]), {ok, Pid}. %% Internal. -spec acceptor(inet:socket(), module(), module(), any(), non_neg_integer(), pid()) -> no_return(). acceptor(LSocket, Transport, Protocol, Opts, MaxConns, ReqsSup) -> case Transport:accept(LSocket, 2000) of {ok, CSocket} -> {ok, Pid} = supervisor:start_child(ReqsSup, [CSocket, Transport, Protocol, Opts]), Transport:controlling_process(CSocket, Pid), limit_reqs(MaxConns, ReqsSup); {error, timeout} -> ignore; {error, _Reason} -> %% @todo Probably do something here. If the socket was closed, %% we may want to try and listen again on the port? ignore end, ?MODULE:acceptor(LSocket, Transport, Protocol, Opts, MaxConns, ReqsSup). -spec limit_reqs(non_neg_integer(), pid()) -> ok. limit_reqs(MaxConns, ReqsSup) -> Counts = supervisor:count_children(ReqsSup), Active = lists:keyfind(active, 1, Counts), case Active < MaxConns of true -> ok; false -> timer:sleep(1) end.