I have a problem with Perl script for Linux. It's main purpose is to be middleman between 3 applications. What it should do:
$udp_port
Problem is my app currently works until the first time I disconnect with TCP client. Then I cannot connect to it any longer, and it times out after it receives next UDP packet on $udp_port
. So basically whenever I want to reconnect with TCP I have to restart app.
All of this should be as fast as possible (every millisecond counts). The text sent to UDP or TCP doesn't contain spaces. It's not necessary to be able to support multiple TCP clients at once, but it would certainly be advantage :-)
Here's my current code:
#!/usr/bin/perl
use strict;
use warnings;
use IO::Socket;
use Net::hostent;
use threads;
use threads::shared;
my $tcp_port = "10008"; # connection from TCP Client
my $udp_port = "2099"; # connection from Announcer
my $udp_password = ""; # password from Announcer
my $title = "Middle Man server version 0.1";
my $tcp_sock = IO::Socket::INET->new( Proto => 'tcp', LocalPort => $tcp_port, Listen => SOMAXCONN,Reuse => 1)|| die @!;
my $udp_sock = new IO::Socket::INET(LocalPort => $udp_port, Proto => "udp") || die @!;
my (@threads);
print "[$title]\n";
sub mySubTcp($)
{
my ($popup) = @_;
print "[TCP][CLIENT CONNECTED]\n";
while (my $answer = <$popup>)
{
chomp $answer;
my ($pass, $announce) = split ' ', $answer;
print $answer . '\n';
}
printf "[TCP][CLIENT DISCONNECTED]\n";
}
my $client = $tcp_sock->accept();
$client->autoflush(1);
my $thr = threads->new(\&mySubTcp, $client);
while ($udp_sock->recv(my $buf, 1024))
{
chomp $buf;
my $announce = $buf;
print "[ANNOUNCE] $announce [START]\n";
print $client $announce . "\n";
print "[ANNOUNCE] $announce [END]\n";
}
Here's the code i tried after couple of suggestions to go without threading. Problem is even thou i am able to connect with TCP Client msg "Trying to setup UDP\n is never displayed. Probably something i'm doing wrong. The tcp client just connects and waits for server to send some data. Udp arrives but it's not accepted. Here's the code:
#!/usr/bin/perl
use strict;
use warnings;
use IO::Socket;
use Net::hostent;
use threads;
use threads::shared;
my $tcp_port = "10008"; # connection from Tcp
my $udp_port = "2099"; # connection from Announcer
my $title = "Middle Man server version 0.2";
my $tcp_sock = IO::Socket::INET->new( Proto => 'tcp', LocalPort => $tcp_port, Listen => SOMAXCONN,Reuse => 1)|| die @!;
my (@threads);
print "[$title]\n";
for (;;)
{
my $open_socket = $tcp_sock->accept();
print "[TCP][CLIENT CONNECTED]\n";
while (my $input = <$open_socket>)
{
print "Trying to setup UDP\n";
my $udp_sock = new IO::Socket::INET(LocalPort => $udp_port, Proto => "udp") || die @!;
while ($udp_sock->recv(my $buf, 1024)) {
chomp $buf;
print "\[ANNOUNCER\] $buf \[START\]\n";
print $open_socket $buf . "\n";
print "\[ANNOUNCER\] $buf \[END\]\n";
}
print "Closing UDP\n";
close $udp_sock;
#chomp $input;
#print $input;
}
close $open_socket;
printf "[TCP][CLIENT DISCONNECTED]\n";
}
What is the maximum number of concurrent TCP connections that a server can handle, in theory ? A single listening port can accept more than one connection simultaneously. There is a '64K' limit that is often cited, but that is per client per server port, and needs clarifying.
The server can receive any number of connections on its single listening port, as long as a different address/port combination is used by each client.
A socket that has been established as a server can accept connection requests from multiple clients.
On the TCP level the tuple (source ip, source port, destination ip, destination port) must be unique for each simultaneous connection. That means a single client cannot open more than 65535 simultaneous connections to a single server. But a server can (theoretically) serve 65535 simultaneous connections per client.
After it disconnects, you'll probably want to loop around and wait for a new connection with ->accept
again.
It would also be a good idea to use strict;
and use warnings;
to ferret out any errors.
Edit: And I don't think glob
does whatever you think it does there.
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