Re^4: multithreaded tcp listener with IO::Socket

[Random_Walk]

hi BrowserUk,

I tried using a thread pool but can not seem to pass the socket handle through the thread queue. Here is the error I get thrown by Thread::Queue. This happens as soon as the first client connects.

Updated, see below

C:\test>perl new_ecg.pl
Server ready. Waiting for connections on 8000 ...
Invalid value for shared scalar at C:/Perl/lib/Thread/Queue.pm line 90
+.
A thread exited while 12 threads were running.

Here is the code I am using

#!/usr/bin/perl
use strict;
use warnings;
use IO::Socket;
use threads;
use Thread::Queue;

#get the port to bind to or default to 8000
my $port = $ARGV[0] || 8000;
my $listeners = 10;

# a hash to record client machines and thread queue for internal comun
+ication
my %clients;
my $mqueue = Thread::Queue -> new;
my $squeue = Thread::Queue -> new;
threads->create ("monitor", $mqueue);
for (1..$listeners) {
    threads->create ("read_data", $mqueue, $squeue)->detach;
}

#create the listen socket
my $listen_socket = IO::Socket::INET->new(LocalPort => $port,
                                          Listen => 20,
                                          Proto => 'tcp',
                                          Reuse => 1);
#make sure we are bound to the port
die "Cant't create a listening socket: $@" unless $listen_socket;
warn "Server ready. Waiting for connections on $port ... \n";

#wait for connections at the accept call
while (my $connection = $listen_socket->accept) {
    # put the connection on the queue for a reader thread
    $squeue -> enqueue($connection);
}

sub read_data {
    # accept data from the socket and put it on the queue
    my ($mqueue, $squeue) = @_;
    while (my $socket = $squeue -> dequeue) {
        while (<$socket>) {
            print "listener got: $_";
            $mqueue -> enqueue(time." $_");
    }
        close $socket;
    }
}

sub monitor {
    my $mqueue = shift;
    while (1) {
        while ($mqueue -> pending) {
            my $data = $mqueue -> dequeue;
            print "monitor got: $data";
            $data =~ /(\d+) Heartbeat from (\S+) next one in (\d+) min
+utes/;
            my $time   = $1;
            my $client = $2;
            my $cycle  = $3;
            if (defined $clients{$client} and $clients{$client} -> [0]
+ eq 'NAK') {
                print "$client sent a beat again\n";
            }
            $clients{$client} = [ 'OK', $time + $cycle * 60 ];
        }
        for my $client (keys %clients) {
            next if $clients{$client}->[0] eq 'NAK';
            next if $clients{$client}->[1] > time;
            print "$client missed a heartbeat, expected at $clients{$c
+lient}->[1], now it is ".time."\n";
            $clients{$client}->[0] = 'NAK';
        }
        sleep 30;
    }
}

Update

I had a search on that error and found Thread::Queue can only handle simple scalar values. I downloaded and installed Thread::Queue::Any which can handle more complex objects but it still looks to choke on the handle ...

[tivadm@rtmr]/home/tivoli/robin$ ./new_ecg.pl
Server ready. Waiting for connections on 8000 ...
Can't store GLOB items at ../../lib/Storable.pm (autosplit into ../../
+lib/auto/Storable/_freeze.al) line 282, at /usr/opt/perl5/lib/site_pe
+rl/5.8.0/Thread/Queue/Any.pm line 30
A thread exited while 12 other threads were still running.

Any suggestions how I can pass the sockets to the thread pool ? Perhaps I can find another data structure that can hold them and then pass some form of pointer to that.

Cheers,
R.