Merge branch 'hans/ssh/fd_more/OTP-12966' into maint

* hans/ssh/fd_more/OTP-12966:
  ssh: testcases for starting daemon with given fd
  ssh: Make it possible for more than one daemon started with option fd

2 files changed, 41 insertions, 3 deletions

diff --git a/lib/ssh/src/ssh.erl b/lib/ssh/src/ssh.erl
index 5bde184070..bb50e436a3 100644
--- a/lib/ssh/src/ssh.erl
+++ b/lib/ssh/src/ssh.erl
@@ -235,10 +235,27 @@ start_daemon(Host, Port, Options, Inet) ->
 	{error, _Reason} = Error ->
 	    Error;
 	{SocketOptions, SshOptions}->
-	    do_start_daemon(Host, Port,[{role, server} |SshOptions] , [Inet | SocketOptions])
+	    try 
+		do_start_daemon(Host, Port,[{role, server} |SshOptions] , [Inet | SocketOptions])
+	    catch
+		throw:bad_fd -> {error,bad_fd};
+		_C:_E -> {error,{cannot_start_daemon,_C,_E}}
+	    end
     end.
     
-do_start_daemon(Host, Port, Options, SocketOptions) ->
+do_start_daemon(Host0, Port0, Options, SocketOptions) ->
+    {Host,Port} = try
+	       case proplists:get_value(fd, SocketOptions) of
+		   undefined ->
+		       {Host0,Port0};
+		   Fd when Port0==0 ->
+		       find_hostport(Fd);
+		   _ ->
+		       {Host0,Port0}
+	       end
+	   catch
+	       _:_ -> throw(bad_fd)
+	   end,
     Profile = proplists:get_value(profile, Options, ?DEFAULT_PROFILE),
     case ssh_system_sup:system_supervisor(Host, Port, Profile) of
 	undefined ->
@@ -272,6 +289,22 @@ do_start_daemon(Host, Port, Options, SocketOptions) ->
 	    end
     end.
 
+find_hostport(Fd) ->
+    %% Using internal functions inet:open/8 and inet:close/0.
+    %% Don't try this at home unless you know what you are doing!
+    {ok,S} = inet:open(Fd, {0,0,0,0}, 0, [], tcp, inet, stream, inet_tcp),
+    {ok, HostPort} = inet:sockname(S),
+    ok = inet:close(S),
+    HostPort.
+    
+%% find_port(Fd) ->
+%%     %% Hack....
+%%     {ok,TmpSock} = gen_tcp:listen(0,[{fd,Fd}]),
+%%     {ok, {_,ThePort}} = inet:sockname(TmpSock),
+%%     gen_tcp:close(TmpSock),
+%%     ThePort.
+
+
 handle_options(Opts) ->
     try handle_option(algs_compatibility(proplists:unfold(Opts)), [], []) of
 	{Inet, Ssh} ->
diff --git a/lib/ssh/src/ssh_acceptor.erl b/lib/ssh/src/ssh_acceptor.erl
index c5ad1d7b6c..d94dedf1bf 100644
--- a/lib/ssh/src/ssh_acceptor.erl
+++ b/lib/ssh/src/ssh_acceptor.erl
@@ -56,7 +56,12 @@ acceptor_init(Parent, Port, Address, SockOpts, Opts, AcceptTimeout) ->
 	    error
     end.
    
-do_socket_listen(Callback, Port, Opts) ->
+do_socket_listen(Callback, Port0, Opts) ->
+    Port =
+	case proplists:get_value(fd, Opts) of
+	    undefined -> Port0;
+	    _ -> 0
+	end,
     case Callback:listen(Port, Opts) of
 	{error, nxdomain} ->
 	    Callback:listen(Port, lists:delete(inet6, Opts));