Ranch Source Analysis (i)

Previously wrote a ranch process, http://www.cnblogs.com/tudou008/p/5197314.html, there is only one picture, not very clear, now have time to do a source analysis.

Ranch source code (version v1.2.1 download link https://github.com/ninenines/ranch.git)

Let's start with one of the simplest examples Tcp_echo

1[Email protected] ranch-master]#pwd2/home/erlang/ranch-Master3[Email protected] ranch-master]# Ll-r examples/tcp_echo/4examples/tcp_echo/:5Total -6-rw-rw-r--1Erlang Erlang AboutJan -  .: theMakefile7-rw-rw-r--1Erlang Erlang543Jan -  .: thereadme.md8-rw-rw-r--1Erlang Erlang -Jan -  .: theRelx.config9Drwxrwxr-x2Erlang Erlang4096May6  the: -srcTen  Oneexamples/tcp_echo/src: ATotal - --rw-rw-r--1Erlang Erlang572Jan -  .: theEcho_protocol.erl --rw-rw-r--1Erlang Erlang346Jan -  .: theTcp_echo_app.erl the-rw-rw-r--1Erlang Erlang284Jan -  .: thetcp_echo.app.src --rw-rw-r--1Erlang Erlang370Jan -  .: theTcp_echo_sup.erl

First View Tcp_echo_app.erl

%%feel free to use, reuse and abuse the code in this file.%%@private-Module(Tcp_echo_app).-behaviour (application).%%API.-Export([START/2]).-Export([STOP/1]).%%API.Start (_type, _args)-{OK, _}=Ranch:start_listener(Tcp_echo, 1, Ranch_tcp, [{port,5555}], Echo_protocol, []), Tcp_echo_sup:start_link (). Stop (_state)-OK.

Can see here, start the Ranch:start_listener

And after we started Tcp_echo_sup:start_link, let's see what Tcp_echo_sup did.

Tcp_echo_sup.erl

%%feel free to use, reuse and abuse the code in this file.%%@private-Module(tcp_echo_sup).-behaviour (supervisor).%%API.-Export([start_link/0]).%%supervisor.-Export([INIT/1]).%%API.-spec Start_link (){OK, pid ()}.start_link ()-Supervisor:start_link ({local,? MODULE},?MODULE, []).%%supervisor.init ([])-{OK, {{one_for_one,10, 10}, []}.

Tcp_echo_sup obviously did not do any business, let's look at the details below Ranch.erl

-Module(Ranch).-Export([START_LISTENER/6]).-Export([STOP_LISTENER/1]).-Export([CHILD_SPEC/6]).-Export([ACCEPT_ACK/1]).-Export([REMOVE_CONNECTION/1]).-Export([GET_ADDR/1]).-Export([GET_PORT/1]).-Export([GET_MAX_CONNECTIONS/1]).-Export([SET_MAX_CONNECTIONS/2]).-Export([GET_PROTOCOL_OPTIONS/1]).-Export([SET_PROTOCOL_OPTIONS/2]).-Export([FILTER_OPTIONS/3]).-Export([SET_OPTION_DEFAULT/3]).-Export([REQUIRE/1]).#...... Omit several lines-spec Start_listener (ref (), Non_neg_integer (), module (), any (), module (), any ())-Supervisor:startchild_ret (). Start_listener (Ref, Nbacceptors, Transport, transopts, Protocol, protoopts) whenIs_integer (nbacceptors)AndAlsoIs_atom (Transport)AndAlsoIs_atom (Protocol)    _ =code:ensure_loaded (Transport),%%@todo Remove in Ranch 2.0 and simply require SSL._ =Ensure_ssl (Transport), CaseErlang:function_exported (Transport, name, 0) of        false-{error, badarg}; true-Res=Supervisor:start_child (Ranch_sup, Child_spec (Ref, Nbacceptors, Transport, transopts, Protocol, Pro toopts)), Socket=proplists:get_value (socket, transopts), CaseRes of{OK, Pid} whenSocket =/= undefined%%Give ownership of the socket to Ranch_acceptors_sup                    %%To make sure the socket stays open as long as the                    %%Listener is alive. If The socket closes however there                    %%'ll be no it's recover because we don ' t know how                    %%To open it again.Children =Supervisor:which_children (Pid), {_, Acceptorssup, _, _}= Lists:keyfind (Ranch_acceptors_sup, 1, children),%%% note:the catch is here because SSL crashes                    %%% The controlling process of a listen socket because of a bug.                    %%% The bug would be a fixed in R16.                    Catchtransport:controlling_process (Socket, acceptorssup); _ -OKEnd, ResEnd.

#...... Omit several lines

The Start_listener starts here,
In comparison with the parameters found in the example, the corresponding values and meanings are as follows

Ref,: Tcp_echo         represents the applied tag
Nbacceptors,  : 1 The                number of processes initiated by the application (that is, the number of ranch_acceptor behind)
Transport: module of the RANCH_TCP Transport layer (RANCH_TCP or RANCH_SSL, can be user-defined)
Transopts,  : [{port, 5555}]   parameters of the transport layer
Protocol,     : echo_protocol    Application Layer Processing module, the general user according to Ranch_protocol writing
Protoopts: [] Application layer parameter definition

Then ranch slowly into our vision, below we slowly analysis ... (not to be continued).

Ranch Source Analysis (i)