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-----------------------------------------------------------------------------
-- --
-- ADASOCKETS COMPONENTS --
-- --
-- T C P R E L A Y --
-- --
-- B o d y --
-- --
-- Copyright (C) 1998-2010 Samuel Tardieu <sam@rfc1149.net> --
-- Copyright (C) 1999-2003 ENST http://www.enst.fr/ --
-- --
-- AdaSockets is free software; you can redistribute it and/or modify --
-- it under terms of the GNU General Public License as published by --
-- the Free Software Foundation; either version 2, or (at your option) --
-- any later version. AdaSockets is distributed in the hope that it --
-- will be useful, but WITHOUT ANY WARRANTY; without even the implied --
-- warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. --
-- See the GNU General Public License for more details. You should --
-- have received a copy of the GNU General Public License distributed --
-- with AdaSockets; see file COPYING. If not, write to the Free --
-- Software Foundation, 59 Temple Place - Suite 330, Boston, MA --
-- 02111-1307, USA. --
-- --
-- As a special exception, if other files instantiate generics from --
-- this unit, or you link this unit with other files to produce an --
-- executable, this unit does not by itself cause the resulting --
-- executable to be covered by the GNU General Public License. This --
-- exception does not however invalidate any other reasons why the --
-- executable file might be covered by the GNU Public License. --
-- --
-- The main repository for this software is located at: --
-- http://www.rfc1149.net/devel/adasockets --
-- --
-- If you have any question, please send a mail to the AdaSockets list --
-- adasockets@lists.rfc1149.net --
-- --
-----------------------------------------------------------------------------
with Ada.Command_Line; use Ada.Command_Line;
with Ada.Exceptions; use Ada.Exceptions;
with Ada.Text_IO; use Ada.Text_IO;
with Sockets; use Sockets;
procedure TCPRelay is
-- Usage: tcprelay localport remotehost remoteport
-- Example: tcprelay 5000 localhost 25,
-- then telnet localhost 5000
task type Relay is
entry Start (From, To : Socket_FD);
end Relay;
-----------
-- Relay --
-----------
task body Relay
is
From_FD, To_FD : Socket_FD;
begin
select
accept Start (From, To : Socket_FD) do
From_FD := From;
To_FD := To;
end Start;
or
terminate;
end select;
loop
Send (To_FD, Receive (From_FD));
end loop;
exception
when Connection_Closed =>
Put_Line ("Connection closed");
Shutdown (From_FD, Receive);
Shutdown (To_FD, Send);
end Relay;
Accepting_Socket,
Incoming_Socket,
Outgoing_Socket : Socket_FD;
type Relay_Access is access Relay;
Dummy : Relay_Access;
begin
if Argument_Count /= 3 then
Raise_Exception
(Constraint_Error'Identity,
"Usage: " & Command_Name & " localport remotehost remoteport");
end if;
Socket (Accepting_Socket, PF_INET, SOCK_STREAM);
Setsockopt (Accepting_Socket, SOL_SOCKET, SO_REUSEADDR, 1);
Bind (Accepting_Socket, Positive'Value (Argument (1)));
Listen (Accepting_Socket);
loop
Put_Line ("Waiting for new connection");
Accept_Socket (Accepting_Socket, Incoming_Socket);
Put_Line ("New connection acknowledged");
Socket (Outgoing_Socket, PF_INET, SOCK_STREAM);
Put_Line ("Connecting to remote host");
Connect (Outgoing_Socket, Argument (2), Positive'Value (Argument (3)));
Put_Line ("Connection established");
Dummy := new Relay;
Dummy.Start (Incoming_Socket, Outgoing_Socket);
Dummy := new Relay;
Dummy.Start (Outgoing_Socket, Incoming_Socket);
end loop;
end TCPRelay;
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