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Diffstat (limited to 'server/_build/default/lib/ranch/src/ranch_conns_sup.erl')
| -rw-r--r-- | server/_build/default/lib/ranch/src/ranch_conns_sup.erl | 325 |
1 files changed, 325 insertions, 0 deletions
diff --git a/server/_build/default/lib/ranch/src/ranch_conns_sup.erl b/server/_build/default/lib/ranch/src/ranch_conns_sup.erl new file mode 100644 index 0000000..fe2237a --- /dev/null +++ b/server/_build/default/lib/ranch/src/ranch_conns_sup.erl @@ -0,0 +1,325 @@ +%% Copyright (c) 2011-2018, Loïc Hoguin <essen@ninenines.eu> +%% +%% 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. + +%% Make sure to never reload this module outside a release upgrade, +%% as calling l(ranch_conns_sup) twice will kill the process and all +%% the currently open connections. +-module(ranch_conns_sup). + +%% API. +-export([start_link/3]). +-export([start_protocol/2]). +-export([active_connections/1]). + +%% Supervisor internals. +-export([init/4]). +-export([system_continue/3]). +-export([system_terminate/4]). +-export([system_code_change/4]). + +-type conn_type() :: worker | supervisor. +-type shutdown() :: brutal_kill | timeout(). + +-record(state, { + parent = undefined :: pid(), + ref :: ranch:ref(), + conn_type :: conn_type(), + shutdown :: shutdown(), + transport = undefined :: module(), + protocol = undefined :: module(), + opts :: any(), + handshake_timeout :: timeout(), + max_conns = undefined :: ranch:max_conns(), + logger = undefined :: module() +}). + +%% API. + +-spec start_link(ranch:ref(), module(), module()) -> {ok, pid()}. +start_link(Ref, Transport, Protocol) -> + proc_lib:start_link(?MODULE, init, + [self(), Ref, Transport, Protocol]). + +%% We can safely assume we are on the same node as the supervisor. +%% +%% We can also safely avoid having a monitor and a timeout here +%% because only three things can happen: +%% * The supervisor died; rest_for_one strategy killed all acceptors +%% so this very calling process is going to di-- +%% * There's too many connections, the supervisor will resume the +%% acceptor only when we get below the limit again. +%% * The supervisor is overloaded, there's either too many acceptors +%% or the max_connections limit is too large. It's better if we +%% don't keep accepting connections because this leaves +%% more room for the situation to be resolved. +%% +%% We do not need the reply, we only need the ok from the supervisor +%% to continue. The supervisor sends its own pid when the acceptor can +%% continue. +-spec start_protocol(pid(), inet:socket()) -> ok. +start_protocol(SupPid, Socket) -> + SupPid ! {?MODULE, start_protocol, self(), Socket}, + receive SupPid -> ok end. + +%% We can't make the above assumptions here. This function might be +%% called from anywhere. +-spec active_connections(pid()) -> non_neg_integer(). +active_connections(SupPid) -> + Tag = erlang:monitor(process, SupPid), + catch erlang:send(SupPid, {?MODULE, active_connections, self(), Tag}, + [noconnect]), + receive + {Tag, Ret} -> + erlang:demonitor(Tag, [flush]), + Ret; + {'DOWN', Tag, _, _, noconnection} -> + exit({nodedown, node(SupPid)}); + {'DOWN', Tag, _, _, Reason} -> + exit(Reason) + after 5000 -> + erlang:demonitor(Tag, [flush]), + exit(timeout) + end. + +%% Supervisor internals. + +-spec init(pid(), ranch:ref(), module(), module()) -> no_return(). +init(Parent, Ref, Transport, Protocol) -> + process_flag(trap_exit, true), + ok = ranch_server:set_connections_sup(Ref, self()), + MaxConns = ranch_server:get_max_connections(Ref), + TransOpts = ranch_server:get_transport_options(Ref), + ConnType = maps:get(connection_type, TransOpts, worker), + Shutdown = maps:get(shutdown, TransOpts, 5000), + HandshakeTimeout = maps:get(handshake_timeout, TransOpts, 5000), + Logger = maps:get(logger, TransOpts, error_logger), + ProtoOpts = ranch_server:get_protocol_options(Ref), + ok = proc_lib:init_ack(Parent, {ok, self()}), + loop(#state{parent=Parent, ref=Ref, conn_type=ConnType, + shutdown=Shutdown, transport=Transport, protocol=Protocol, + opts=ProtoOpts, handshake_timeout=HandshakeTimeout, + max_conns=MaxConns, logger=Logger}, 0, 0, []). + +loop(State=#state{parent=Parent, ref=Ref, conn_type=ConnType, + transport=Transport, protocol=Protocol, opts=Opts, + max_conns=MaxConns, logger=Logger}, CurConns, NbChildren, Sleepers) -> + receive + {?MODULE, start_protocol, To, Socket} -> + try Protocol:start_link(Ref, Socket, Transport, Opts) of + {ok, Pid} -> + handshake(State, CurConns, NbChildren, Sleepers, To, Socket, Pid, Pid); + {ok, SupPid, ProtocolPid} when ConnType =:= supervisor -> + handshake(State, CurConns, NbChildren, Sleepers, To, Socket, SupPid, ProtocolPid); + Ret -> + To ! self(), + ranch:log(error, + "Ranch listener ~p connection process start failure; " + "~p:start_link/4 returned: ~999999p~n", + [Ref, Protocol, Ret], Logger), + Transport:close(Socket), + loop(State, CurConns, NbChildren, Sleepers) + catch Class:Reason -> + To ! self(), + ranch:log(error, + "Ranch listener ~p connection process start failure; " + "~p:start_link/4 crashed with reason: ~p:~999999p~n", + [Ref, Protocol, Class, Reason], Logger), + loop(State, CurConns, NbChildren, Sleepers) + end; + {?MODULE, active_connections, To, Tag} -> + To ! {Tag, CurConns}, + loop(State, CurConns, NbChildren, Sleepers); + %% Remove a connection from the count of connections. + {remove_connection, Ref, Pid} -> + case put(Pid, removed) of + active -> + loop(State, CurConns - 1, NbChildren, Sleepers); + remove -> + loop(State, CurConns, NbChildren, Sleepers); + undefined -> + _ = erase(Pid), + loop(State, CurConns, NbChildren, Sleepers) + end; + %% Upgrade the max number of connections allowed concurrently. + %% We resume all sleeping acceptors if this number increases. + {set_max_conns, MaxConns2} when MaxConns2 > MaxConns -> + _ = [To ! self() || To <- Sleepers], + loop(State#state{max_conns=MaxConns2}, + CurConns, NbChildren, []); + {set_max_conns, MaxConns2} -> + loop(State#state{max_conns=MaxConns2}, + CurConns, NbChildren, Sleepers); + %% Upgrade the protocol options. + {set_opts, Opts2} -> + loop(State#state{opts=Opts2}, + CurConns, NbChildren, Sleepers); + {'EXIT', Parent, Reason} -> + terminate(State, Reason, NbChildren); + {'EXIT', Pid, Reason} when Sleepers =:= [] -> + case erase(Pid) of + active -> + report_error(Logger, Ref, Protocol, Pid, Reason), + loop(State, CurConns - 1, NbChildren - 1, Sleepers); + removed -> + report_error(Logger, Ref, Protocol, Pid, Reason), + loop(State, CurConns, NbChildren - 1, Sleepers); + undefined -> + loop(State, CurConns, NbChildren, Sleepers) + end; + %% Resume a sleeping acceptor if needed. + {'EXIT', Pid, Reason} -> + case erase(Pid) of + active when CurConns > MaxConns -> + report_error(Logger, Ref, Protocol, Pid, Reason), + loop(State, CurConns - 1, NbChildren - 1, Sleepers); + active -> + report_error(Logger, Ref, Protocol, Pid, Reason), + [To|Sleepers2] = Sleepers, + To ! self(), + loop(State, CurConns - 1, NbChildren - 1, Sleepers2); + removed -> + report_error(Logger, Ref, Protocol, Pid, Reason), + loop(State, CurConns, NbChildren - 1, Sleepers); + undefined -> + loop(State, CurConns, NbChildren, Sleepers) + end; + {system, From, Request} -> + sys:handle_system_msg(Request, From, Parent, ?MODULE, [], + {State, CurConns, NbChildren, Sleepers}); + %% Calls from the supervisor module. + {'$gen_call', {To, Tag}, which_children} -> + Children = [{Protocol, Pid, ConnType, [Protocol]} + || {Pid, Type} <- get(), + Type =:= active orelse Type =:= removed], + To ! {Tag, Children}, + loop(State, CurConns, NbChildren, Sleepers); + {'$gen_call', {To, Tag}, count_children} -> + Counts = case ConnType of + worker -> [{supervisors, 0}, {workers, NbChildren}]; + supervisor -> [{supervisors, NbChildren}, {workers, 0}] + end, + Counts2 = [{specs, 1}, {active, NbChildren}|Counts], + To ! {Tag, Counts2}, + loop(State, CurConns, NbChildren, Sleepers); + {'$gen_call', {To, Tag}, _} -> + To ! {Tag, {error, ?MODULE}}, + loop(State, CurConns, NbChildren, Sleepers); + Msg -> + ranch:log(error, + "Ranch listener ~p received unexpected message ~p~n", + [Ref, Msg], Logger), + loop(State, CurConns, NbChildren, Sleepers) + end. + +handshake(State=#state{ref=Ref, transport=Transport, handshake_timeout=HandshakeTimeout, + max_conns=MaxConns}, CurConns, NbChildren, Sleepers, To, Socket, SupPid, ProtocolPid) -> + case Transport:controlling_process(Socket, ProtocolPid) of + ok -> + ProtocolPid ! {handshake, Ref, Transport, Socket, HandshakeTimeout}, + put(SupPid, active), + CurConns2 = CurConns + 1, + if CurConns2 < MaxConns -> + To ! self(), + loop(State, CurConns2, NbChildren + 1, Sleepers); + true -> + loop(State, CurConns2, NbChildren + 1, [To|Sleepers]) + end; + {error, _} -> + Transport:close(Socket), + %% Only kill the supervised pid, because the connection's pid, + %% when different, is supposed to be sitting under it and linked. + exit(SupPid, kill), + To ! self(), + loop(State, CurConns, NbChildren, Sleepers) + end. + +-spec terminate(#state{}, any(), non_neg_integer()) -> no_return(). +terminate(#state{shutdown=brutal_kill}, Reason, _) -> + kill_children(get_keys(active)), + kill_children(get_keys(removed)), + exit(Reason); +%% Attempt to gracefully shutdown all children. +terminate(#state{shutdown=Shutdown}, Reason, NbChildren) -> + shutdown_children(get_keys(active)), + shutdown_children(get_keys(removed)), + _ = if + Shutdown =:= infinity -> + ok; + true -> + erlang:send_after(Shutdown, self(), kill) + end, + wait_children(NbChildren), + exit(Reason). + +%% Kill all children and then exit. We unlink first to avoid +%% getting a message for each child getting killed. +kill_children(Pids) -> + _ = [begin + unlink(P), + exit(P, kill) + end || P <- Pids], + ok. + +%% Monitor processes so we can know which ones have shutdown +%% before the timeout. Unlink so we avoid receiving an extra +%% message. Then send a shutdown exit signal. +shutdown_children(Pids) -> + _ = [begin + monitor(process, P), + unlink(P), + exit(P, shutdown) + end || P <- Pids], + ok. + +wait_children(0) -> + ok; +wait_children(NbChildren) -> + receive + {'DOWN', _, process, Pid, _} -> + case erase(Pid) of + active -> wait_children(NbChildren - 1); + removed -> wait_children(NbChildren - 1); + _ -> wait_children(NbChildren) + end; + kill -> + Active = get_keys(active), + _ = [exit(P, kill) || P <- Active], + Removed = get_keys(removed), + _ = [exit(P, kill) || P <- Removed], + ok + end. + +system_continue(_, _, {State, CurConns, NbChildren, Sleepers}) -> + loop(State, CurConns, NbChildren, Sleepers). + +-spec system_terminate(any(), _, _, _) -> no_return(). +system_terminate(Reason, _, _, {State, _, NbChildren, _}) -> + terminate(State, Reason, NbChildren). + +system_code_change(Misc, _, _, _) -> + {ok, Misc}. + +%% We use ~999999p here instead of ~w because the latter doesn't +%% support printable strings. +report_error(_, _, _, _, normal) -> + ok; +report_error(_, _, _, _, shutdown) -> + ok; +report_error(_, _, _, _, {shutdown, _}) -> + ok; +report_error(Logger, Ref, Protocol, Pid, Reason) -> + ranch:log(error, + "Ranch listener ~p had connection process started with " + "~p:start_link/4 at ~p exit with reason: ~999999p~n", + [Ref, Protocol, Pid, Reason], Logger). |