Merge branch 'uw/extending_gen' into maint

* uw/extending_gen:
  Add plugin support for alternative name lookup

OTP-9945

1 files changed, 94 insertions, 0 deletions

diff --git a/lib/stdlib/test/dummy_via.erl b/lib/stdlib/test/dummy_via.erl
new file mode 100644
index 0000000000..e405811cbe
--- /dev/null
+++ b/lib/stdlib/test/dummy_via.erl
@@ -0,0 +1,94 @@
+-module(dummy_via).
+-export([reset/0,
+	 register_name/2,
+	 whereis_name/1,
+	 unregister_name/1,
+	 send/2]).
+
+
+reset() ->
+    P = whereis(?MODULE),
+    catch unlink(P),
+    Ref = erlang:monitor(process, P),
+    catch exit(P, kill),
+    receive {'DOWN',Ref,_,_,_} -> ok end,
+    Me = self(),
+    Pid = spawn_link(fun() ->
+			     register(?MODULE, self()),
+			     Me ! {self(), started},
+			     loop([])
+		     end),
+    receive
+	{Pid, started} ->
+	    Pid
+    after 10000 ->
+	    exit(timeout)
+    end.
+
+register_name(Name, Pid) when is_pid(Pid) ->
+    call({register_name, Name, Pid}).
+
+unregister_name(Name) ->
+    call({unregister_name, Name}).
+
+whereis_name(Name) ->
+    call({whereis_name, Name}).
+
+send(Name, Msg) ->
+    case whereis_name(Name) of
+	undefined ->
+	    exit({badarg, {Name, Msg}});
+	Pid when is_pid(Pid) ->
+	    Pid ! Msg,
+	    Pid
+    end.
+
+call(Req) ->
+    MRef = erlang:monitor(process, ?MODULE),
+    ?MODULE ! {self(), MRef, Req},
+    receive
+	{'DOWN', MRef, _, _, _} ->
+	    erlang:error(badarg);
+	{MRef, badarg} ->
+	    erlang:error(badarg);
+	{MRef, Reply} ->
+	    Reply
+    after 5000 ->
+	    erlang:error(timeout)
+    end.
+
+loop(Reg) ->
+    receive
+	{'DOWN', _, _, P, _} when is_pid(P) ->
+	    loop([X || {_,Pid,_} = X <- Reg, Pid =/= P]);
+	{From, Ref, Request} when is_pid(From), is_reference(Ref) ->
+	    {Reply, NewReg} = handle_request(Request, Reg),
+	    From ! {Ref, Reply},
+	    loop(NewReg)
+    end.
+
+handle_request({register_name, Name, Pid}, Reg) when is_pid(Pid) ->
+    case lists:keyfind(Name, 1, Reg) of
+	false ->
+	    Ref = erlang:monitor(process, Pid),
+	    {yes, [{Name, Pid, Ref}|Reg]};
+	_ ->
+	    {no, Reg}
+    end;
+handle_request({whereis_name, Name}, Reg) ->
+    case lists:keyfind(Name, 1, Reg) of
+	{_, Pid, _} ->
+	    {Pid, Reg};
+	false ->
+	    {undefined, Reg}
+    end;
+handle_request({unregister_name, Name}, Reg) ->
+    case lists:keyfind(Name, 1, Reg) of
+	{_, _, Ref} ->
+	    catch erlang:demonitor(Ref);
+	_ ->
+	    ok
+    end,
+    {ok, lists:keydelete(Name, 1, Reg)};
+handle_request(_, Reg) ->
+    {badarg, Reg}.