#!/usr/bin/perl -w

use Time::HiRes;
use IO::Socket;
use IO::Select;
use threads;
use threads::shared;
use Thread::Queue;

$SIG{"INT"}=\&sigInt;      # for ^C
$SIG{"PIPE"}=\&sigPipe;    # socket comm errors

my %sockConns;
share(%sockConns);

$q1 = new Thread::Queue;
$q2 = new Thread::Queue;
my $thread=threads->create('manageSock', $q1, $q2)->detach;

my $done=0;
my $count=0;
while(!$done)
{
    print "top\n";

  $count++;
  lock(%sockConns);
  foreach my $fn (keys %sockConns)
  {
    logit("FN: $fn=$sockConns{$fn}");
    if ($sockConns{$fn}==-1)
    {
      logit(">>>Close 1st: $fn");
      $sockOpened{$fn}->close()    if defined($sockOpened{$fn});
      delete $sockOpened{$fn};
      delete $sockConns{$fn};
      $q1->enqueue($fn);
      my $wait=$q2->dequeue;
      logit("Continue...");
      last;
    }

    if (!defined($sockOpened{$fn}) && !open($sockOpened{$fn}, ">&$fn"))
    {
      print "Couldn't open socket $fn for writing\n";
      next;
    }

    logit("Write: $count TO: $fn");
    $bytes=syswrite($sockOpened{$fn}, "$count/n", length($count)+1, 0);

    # Do nothing as socket will disconnet and normal cleanup will kick in
    if (!$bytes)
    {
      logit("========================> Comm Failure <====================");
      last;
    }
    logit("Wrote $bytes bytes");
  }
  sleep 1;  # uncomment to slow responses down
#  print "awake\n";
}

sub manageSock
{
  my $q1=shift;
  my $q2=shift;

  $port=2655;
  my $sockServer = new IO::Socket::INET(
        Type=>SOCK_STREAM,
        Reuse=>1, Listen => 1,
        LocalPort => $port) ||
        error("Could not create local socket on port $port");
  logit("Server socket opened on port $port");
  my $select=new IO::Select($sockServer);

  while(1)
  {
    logit("Waiting on socket");
    while (my @ready=$select->can_read)
    {
      my $saveFnum;
      my $saveHandle;
      my $waitForClose=0;
      foreach my $filehandle (@ready)
      {
        lock(%sockConns);
        logit("Socket 'can read'");

        if ($filehandle==$sockServer)
        {
          my $new=$sockServer->accept() || logmsg('E', "Couldn't accept connection request");
          $select->add($new);
          my $fnum=$new->fileno();
          $sockConns{$fnum}=0;
          $sockNumConn++;

          logit("Connection on FN: $fnum");
        }
        else
        {
          my $message=<$filehandle>;
          my $fnum=$filehandle->fileno();
          if (!defined($message))
          {
            logit("Client Disconnect FN: $fnum");

            $saveFnum=$fnum;
            $saveHandle=$filehandle;
            $waitForClose=1;
            $sockConns{$fnum}=-1;
            last;
          }
          else
          {
            logit("Ignoring: $message");
          }
        }
      }

      if ($waitForClose)
      {
        logit("Waiting for 1st socket close");
        my $fnum=$q1->dequeue;
        $select->remove($saveHandle);
        $saveHandle->close();
        $sockNumConn--;
        $q2->enqueue($fnum);    # tell main process OK to release lock
      }
    }
  }
}

sub sigPipe
{
  #trap but ignore
}

sub sigInt
{
    print "^C\n";
    $done=1;
}

sub logit
{
    my $text=shift;
    my ($intSeconds, $intUsecs)=Time::HiRes::gettimeofday();
    $time=sprintf("$intSeconds.%06d", $intUsecs);
    print "$time $text\n";
}