#!/usr/bin/perl 
# require 5.002;

use strict;
BEGIN { $ENV{PATH} = '/usr/ucb:/bin' }
use Socket qw( 
   getaddrinfo getnameinfo IN6ADDR_ANY AF_UNSPEC SOCK_STREAM PF_UNSPEC 
   AI_PASSIVE NI_NUMERICHOST  NI_NUMERICSERV SOL_SOCKET SO_REUSEADDR SOMAXCONN
);

use Carp;
use IO::Select;

my $myself = "$0 ";
sub logmsg { print "$myself $$: @_ at ", scalar localtime, "\n" }

my $host = shift || IN6ADDR_ANY;
my $port = shift || 2345;
my $proto = getprotobyname('tcp');

my $select = &bind_sockets($host,$port);

logmsg "server started on port $port";

my %address_list;

my $paddr;

my $count = 0;

while(my @ready = $select->can_read()) {
    for my $socket ( @ready ) {
	my $paddr =  accept(my $client, $socket);
	next if (! $paddr) ;

	my ($err,$addr,$m) = getnameinfo($paddr,NI_NUMERICHOST); 
	my ($err,$name,$port) = getnameinfo($paddr,NI_NUMERICSERV); 
        $address_list{$addr} = $name;
        $count ++;

        my $user = <$client>;
        $user=~ s/[\r\n]//g;
	logmsg "connection from $user \@ $name [",
	     $addr, "]
	     at port $port count = $count";

	print $client "Hello there, $name, it's now ",
		     scalar localtime, " coount = $count \n";
        foreach my $k (keys %address_list) {
	    print $client "$k = $address_list{$k}\n";
        }
	close($client);
    }
}

sub bind_sockets {
    my ($host0,$port0) = @_;
    my $select = IO::Select->new();

    my ($err,@res) = getaddrinfo($host0, $port0,{socktype=>SOCK_STREAM, flags=>AI_PASSIVE});
    my @socket;
    my (@host);
    for my $res (@res) { 
        my ($family, $socktype, $proto, $saddr, $canonname) = ( $res->{family} , $res->{socktype}, $res->{protocol}, $res->{addr}, $res->{canonname} );
        my ($host, $port) = getnameinfo($saddr,NI_NUMERICHOST | NI_NUMERICSERV);
        print STDERR "Trying to bind to $host : $port... ";
        socket(my $fd, $family, $socktype, $proto) || next;
	setsockopt($fd, SOL_SOCKET, SO_REUSEADDR, pack("l", 1))   || die "setsockopt : $!";

	if (bind($fd, $saddr)) { # sockaddr_in($port, INADDR_ANY)
	    listen($fd,SOMAXCONN)  || die "listen: $!  ";
            $select->add($fd);
	    print STDERR "connected.\n";
	} else {
	    print STDERR "failed.\n";
	    close($fd);
        }
    }

    if ($select->count == 0) {
        die "connect attempt failed\n";
    }
    return $select;

}


sub accepts {
    my ($c, @sockets) = @_;    # $c is dummy
}