#!/usr/bin/perl
use strict;
use DBI;
use Socket;

foreach my $ether (split(/\s+/, get_ethers_by_host(shift())))
{
    wake_host_by_hwaddr($ether);
}

exit (0);


sub wake_host_by_hwaddr
{
    my ($packet, $hwaddr, $raddr, $port);

    foreach (split /:/, $_[0])
    {
        $hwaddr .= chr(hex($_));
    }
    $packet = chr(0xFF) x 6 . $hwaddr x 16;
    
    socket((SOCK, AF_INET, SOCK_DGRAM, getprotobyname('udp'))) || die "socket : $!";
    setsockopt(SOCK, SOL_SOCKET, SO_BROADCAST, 1) || die "setsockopt : $!";

    $port = getservbyname('discard', 'udp');
    $raddr = gethostbyname('255.255.255.255');
    send(SOCK, $packet, 0, pack_sockaddr_in($port, $raddr)) || die "send : $!";

    close (SOCK);

    return;
}


sub get_ethers_by_host
{
    my ($dbh, $sth, $query, $ethers);

    $dbh = open_db();
    $query = sprintf('SELECT ethers FROM ethers WHERE hostname = \'%s\'',
                     $_[0]);
    $sth = $dbh->prepare($query);
    $sth->execute || die "Error:" . $dbh->errstr . "\n";
    while (my $ref = $sth->fetchrow_arrayref)
    {
        $ethers = $$ref[0];
    }
    $sth->finish();
    $dbh->disconnect();

    return ($ethers);
}


sub open_db
{
    my $home = $ENV{'HOME'};
    my ($dsn, $dbh, $user, $password);

    $dsn = "DBI:mysql:database=ethers;"
         . "mysql_read_default_group=ethers;"
         . "mysql_read_default_file=$home/.my.cnf;"
         . "mysql_mysql_client_found_rows=TRUE;"
         . "mysql_mysql_ssl=TRUE";

    $dbh = DBI->connect($dsn, undef, undef, {RaiseError => 1, AutoCommit => 0});

    return ($dbh);
}