#!/usr/bin/perl -w

#
# $Id: program,v 1.11 2002/03/09 02:19:09 jj Exp $
#
# Author: Shannon -jj Behrens
# Date: Tue Sep 11 13:52:16 PDT 2001
#

use strict;

# Read "man getaddrinfo", "perldoc Socket6", and "perldoc perlipc".
use Socket;
use Socket6;

# This is the port we should listen to for incoming bell
# requests.
$::BELL_PORT = 1029;


#
# A lot of other code has been snipped.
#


# This is a stub function that will do something with a 
# host and two ports.
sub ring_bell {
    my ($pip, $vic_port, $rat_port) = @_;
    print "pip: $pip vic_port: $vic_port " . 
          "rat_port: $rat_port\n";
}


# Open up a socket on $::BELL_PORT.  If a connection is
# received, accept the Vic and Rat port values, call 
# ring_bell, and disconnect.  This function must
# be called from a forked process before Tk is used.  This
# function does not return.  
sub bell_daemon {
    my @addrinfo = getaddrinfo("", $::BELL_PORT, PF_INET6,
                               SOCK_STREAM, 0, AI_PASSIVE);
    if (scalar(@addrinfo) < 5) { 
        die "Error while trying to bind to port.  " . 
            "Reason: $1";
    }
    my ($family, $socktype, $proto, $saddr) = @addrinfo;
    socket SERVER, $family, $socktype, $proto ||
        die "Couldn't create socket.  Reason: $1";
    setsockopt SERVER, SOL_SOCKET, SO_REUSEADDR, 
        pack("l", 1) ||
        die "Couldn't set socket options.  Reason: $1";
    bind SERVER, $saddr || 
        die "Couldn't bind to socket.  Reason: $1";
    listen SERVER, SOMAXCONN || 
        die "Couldn't call listen on socket.  Reason: $1";

    for ( ; my $paddr = accept CLIENT, SERVER; 
         close CLIENT) {
        my ($pip, $pport) = 
            getnameinfo($paddr, 
                NI_NUMERICHOST | NI_NUMERICSERV);
        my $line;
        if (!defined($line = <CLIENT>)) {
            warn "connecting socket didn't send " . 
                 "port values";
            next;
        }
        my @port_values = split / /, $line;
        if (scalar(@port_values) != 2) { 
            warn "connecting socket didn't send exactly " .
                 "two port values";
            next;
        }
        my ($vic_port, $rat_port) = @port_values;
        ring_bell $pip, $vic_port, $rat_port;
    }

    close SERVER;
}


bell_daemon;