%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2008-2010. All Rights Reserved.
%%
%% The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
%% compliance with the License. You should have received a copy of the
%% Erlang Public License along with this software. If not, it can be
%% retrieved online at http://www.erlang.org/.
%%
%% Software distributed under the License is distributed on an "AS IS"
%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
%% the License for the specific language governing rights and limitations
%% under the License.
%%
%% %CopyrightEnd%
%%
%%
%%----------------------------------------------------------------------
%% Purpose: The ssh server instance supervisor, an instans of this supervisor
%% exists for every ip-address and port combination, hangs under
%% sshd_sup.
%%----------------------------------------------------------------------
-module(ssh_system_sup).
-behaviour(supervisor).
-export([start_link/1, stop_listener/1,
stop_listener/2, stop_system/1,
stop_system/2, system_supervisor/2,
subsystem_supervisor/1, channel_supervisor/1,
connection_supervisor/1,
acceptor_supervisor/1, start_subsystem/2, restart_subsystem/2,
restart_acceptor/2, stop_subsystem/2]).
%% Supervisor callback
-export([init/1]).
%%%=========================================================================
%%% API
%%%=========================================================================
start_link(ServerOpts) ->
Address = proplists:get_value(address, ServerOpts),
Port = proplists:get_value(port, ServerOpts),
Name = make_name(Address, Port),
supervisor:start_link({local, Name}, ?MODULE, [ServerOpts]).
stop_listener(SysSup) ->
stop_acceptor(SysSup).
stop_listener(Address, Port) ->
Name = make_name(Address, Port),
stop_acceptor(whereis(Name)).
stop_system(SysSup) ->
Name = sshd_sup:system_name(SysSup),
sshd_sup:stop_child(Name).
stop_system(Address, Port) ->
sshd_sup:stop_child(Address, Port).
system_supervisor(Address, Port) ->
Name = make_name(Address, Port),
whereis(Name).
subsystem_supervisor(SystemSup) ->
ssh_subsystem_sup(supervisor:which_children(SystemSup)).
channel_supervisor(SystemSup) ->
SubSysSup = ssh_subsystem_sup(supervisor:which_children(SystemSup)),
ssh_subsystem_sup:channel_supervisor(SubSysSup).
connection_supervisor(SystemSup) ->
SubSysSup = ssh_subsystem_sup(supervisor:which_children(SystemSup)),
ssh_subsystem_sup:connection_supervisor(SubSysSup).
acceptor_supervisor(SystemSup) ->
ssh_acceptor_sup(supervisor:which_children(SystemSup)).
start_subsystem(SystemSup, Options) ->
Spec = ssh_subsystem_child_spec(Options),
supervisor:start_child(SystemSup, Spec).
stop_subsystem(SystemSup, SubSys) ->
case catch lists:keyfind(SubSys, 2, supervisor:which_children(SystemSup)) of
false ->
{error, not_found};
{Id, _, _, _} ->
spawn(fun() -> supervisor:terminate_child(SystemSup, Id),
supervisor:delete_child(SystemSup, Id) end),
ok;
{'EXIT', {noproc, _}} ->
%% Already terminated; probably shutting down.
ok;
{'EXIT', {shutdown, _}} ->
%% Already shutting down.
ok
end.
restart_subsystem(Address, Port) ->
SysSupName = make_name(Address, Port),
SubSysName = id(ssh_subsystem_sup, Address, Port),
case supervisor:terminate_child(SysSupName, SubSysName) of
ok ->
supervisor:restart_child(SysSupName, SubSysName);
Error ->
Error
end.
restart_acceptor(Address, Port) ->
SysSupName = make_name(Address, Port),
AcceptorName = id(ssh_acceptor_sup, Address, Port),
supervisor:restart_child(SysSupName, AcceptorName).
%%%=========================================================================
%%% Supervisor callback
%%%=========================================================================
init([ServerOpts]) ->
RestartStrategy = one_for_one,
MaxR = 10,
MaxT = 3600,
Children = child_specs(ServerOpts),
{ok, {{RestartStrategy, MaxR, MaxT}, Children}}.
%%%=========================================================================
%%% Internal functions
%%%=========================================================================
child_specs(ServerOpts) ->
[ssh_acceptor_child_spec(ServerOpts)].
ssh_acceptor_child_spec(ServerOpts) ->
Address = proplists:get_value(address, ServerOpts),
Port = proplists:get_value(port, ServerOpts),
Name = id(ssh_acceptor_sup, Address, Port),
StartFunc = {ssh_acceptor_sup, start_link, [ServerOpts]},
Restart = permanent,
Shutdown = infinity,
Modules = [ssh_acceptor_sup],
Type = supervisor,
{Name, StartFunc, Restart, Shutdown, Type, Modules}.
ssh_subsystem_child_spec(ServerOpts) ->
Name = make_ref(),
StartFunc = {ssh_subsystem_sup, start_link, [ServerOpts]},
Restart = temporary,
Shutdown = infinity,
Modules = [ssh_subsystem_sup],
Type = supervisor,
{Name, StartFunc, Restart, Shutdown, Type, Modules}.
id(Sup, Address, Port) ->
{Sup, Address, Port}.
make_name(Address, Port) ->
list_to_atom(lists:flatten(io_lib:format("ssh_system_~p_~p_sup",
[Address, Port]))).
ssh_subsystem_sup([{_, Child, _, [ssh_subsystem_sup]} | _]) ->
Child;
ssh_subsystem_sup([_ | Rest]) ->
ssh_subsystem_sup(Rest).
ssh_acceptor_sup([{_, Child, _, [ssh_acceptor_sup]} | _]) ->
Child;
ssh_acceptor_sup([_ | Rest]) ->
ssh_acceptor_sup(Rest).
stop_acceptor(Sup) ->
[Name] =
[SupName || {SupName, _, _, [ssh_acceptor_sup]} <-
supervisor:which_children(Sup)],
supervisor:terminate_child(Sup, Name).
