add checks for other Win32 POSIX substitutes

[spider.git] / perl / DXProtHandle.pm

#
#
# This module impliments the handlers for the protocal mode for a dx cluster
#
# Copyright (c) 1998-2007 Dirk Koopman G1TLH
#
#
#

package DXProt;

@ISA = qw(DXChannel);

use DXUtil;
use DXChannel;
use DXUser;
use DXM;
use DXProtVars;
use DXCommandmode;
use DXLog;
use Spot;
use DXProtout;
use DXDebug;
use Filter;
use Local;
use DXDb;
use AnnTalk;
use Geomag;
use WCY;
use BadWords;
use DXHash;
use Route;
use Route::Node;
use Script;
use RouteDB;


use strict;

use vars qw($pc11_max_age $pc23_max_age $last_pc50 $eph_restime $eph_info_restime $eph_pc34_restime
                        $last_hour $last10 %eph  %pings %rcmds $ann_to_talk
                        $pingint $obscount %pc19list $chatdupeage $chatimportfn
                        $investigation_int $pc19_version $myprot_version
                        %nodehops $baddx $badspotter $badnode $censorpc
                        $allowzero $decode_dk0wcy $send_opernam @checklist
                        $eph_pc15_restime $pc9x_past_age $pc9x_dupe_age
                        $pc10_dupe_age $pc92_slug_changes $last_pc92_slug
                        $pc92Ain $pc92Cin $pc92Din $pc92Kin $pc9x_time_tolerance
                   );

$pc9x_dupe_age = 60;                    # catch loops of circular (usually) D records
$pc10_dupe_age = 45;                    # just something to catch duplicate PC10->PC93 conversions
$pc92_slug_changes = 60;                # slug any changes going outward for this long
$last_pc92_slug = 0;                    # the last time we sent out any delayed add or del PC92s
$pc9x_time_tolerance = 15*60;   # the time on a pc9x is allowed to be out by this amount
$pc9x_past_age = (122*60)+              # maximum age in the past of a px9x (a config record might be the only
        $pc9x_time_tolerance;           # thing a node might send - once an hour and we allow an extra hour for luck)
                                # this is actually the partition between "yesterday" and "today" but old.


# incoming talk commands
sub handle_10
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;

        # this is to catch loops caused by bad software ...
        if (eph_dup($line, $pc10_dupe_age)) {
                return;
        }

        # will we allow it at all?
        if ($censorpc) {
                my @bad;
                if (@bad = BadWords::check($_[3])) {
                        dbg("PCPROT: Bad words: @bad, dropped") if isdbg('chanerr');
                        return;
                }
        }

        # is it for me or one of mine?
        my ($from, $to, $via, $call, $dxchan);
        $from = $_[1];
        if ($_[5] gt ' ') {
                $via = $_[2];
                $to = $_[5];
        } else {
                $to = $_[2];
        }

        # if this is a 'nodx' node then ignore it
        if ($badnode->in($_[6]) || ($via && $badnode->in($via))) {
                dbg("PCPROT: Bad Node, dropped") if isdbg('chanerr');
                return;
        }

        # if this is a 'bad spotter' user then ignore it
        my $nossid = $from;
        $nossid =~ s/-\d+$//;
        if ($badspotter->in($nossid)) {
                dbg("PCPROT: Bad Spotter, dropped") if isdbg('chanerr');
                return;
        }

        # if we are converting announces to talk is it a dup?
        if ($ann_to_talk) {
                if (AnnTalk::is_talk_candidate($from, $_[3]) && AnnTalk::dup($from, $to, $_[3])) {
                        dbg("PCPROT: Dupe talk from announce, dropped") if isdbg('chanerr');
                        return;
                }
        }

        # remember a route to this node and also the node on which this user is
        RouteDB::update($_[6], $self->{call});
#       RouteDB::update($to, $_[6]);

        # convert this to a PC93, coming from mycall with origin set and process it as such
        $main::me->normal(pc93($to, $from, $via, $_[3], $_[6]));
}

# DX Spot handling
sub handle_11
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;

        # route 'foreign' pc26s
        if ($pcno == 26) {
                if ($_[7] ne $main::mycall) {
                        $self->route($_[7], $line);
                        return;
                }
        }

#       my ($hops) = $_[8] =~ /^H(\d+)/;

        # is the spotted callsign blank? This should really be trapped earlier but it
        # could break other protocol sentences. Also check for lower case characters.
        if ($_[2] =~ /^\s*$/) {
                dbg("PCPROT: blank callsign, dropped") if isdbg('chanerr');
                return;
        }
        if ($_[2] =~ /[a-z]/) {
                dbg("PCPROT: lowercase characters, dropped") if isdbg('chanerr');
                return;
        }


        # if this is a 'nodx' node then ignore it
        if ($badnode->in($_[7])) {
                dbg("PCPROT: Bad Node, dropped") if isdbg('chanerr');
                return;
        }

        # if this is a 'bad spotter' user then ignore it
        my $nossid = $_[6];
        $nossid =~ s/-\d+$//;
        if ($badspotter->in($nossid)) {
                dbg("PCPROT: Bad Spotter, dropped") if isdbg('chanerr');
                return;
        }

        # convert the date to a unix date
        my $d = cltounix($_[3], $_[4]);
        # bang out (and don't pass on) if date is invalid or the spot is too old (or too young)
        if (!$d || ($pcno == 11 && ($d < $main::systime - $pc11_max_age || $d > $main::systime + 900))) {
                dbg("PCPROT: Spot ignored, invalid date or out of range ($_[3] $_[4])\n") if isdbg('chanerr');
                return;
        }

        # is it 'baddx'
        if ($baddx->in($_[2]) || BadWords::check($_[2]) || $_[2] =~ /COCK/) {
                dbg("PCPROT: Bad DX spot, ignored") if isdbg('chanerr');
                return;
        }

        # do some de-duping
        $_[5] =~ s/^\s+//;                      # take any leading blanks off
        $_[2] = unpad($_[2]);           # take off leading and trailing blanks from spotted callsign
        if ($_[2] =~ /BUST\w*$/) {
                dbg("PCPROT: useless 'BUSTED' spot") if isdbg('chanerr');
                return;
        }
        if ($censorpc) {
                my @bad;
                if (@bad = BadWords::check($_[5])) {
                        dbg("PCPROT: Bad words: @bad, dropped") if isdbg('chanerr');
                        return;
                }
        }

        # remember a route
#       RouteDB::update($_[7], $self->{call});
#       RouteDB::update($_[6], $_[7]);

        my @spot = Spot::prepare($_[1], $_[2], $d, $_[5], $nossid, $_[7]);
        # global spot filtering on INPUT
        if ($self->{inspotsfilter}) {
                my ($filter, $hops) = $self->{inspotsfilter}->it(@spot);
                unless ($filter) {
                        dbg("PCPROT: Rejected by input spot filter") if isdbg('chanerr');
                        return;
                }
        }

        # this goes after the input filtering, but before the add
        # so that if it is input filtered, it isn't added to the dup
        # list. This allows it to come in from a "legitimate" source
        if (Spot::dup(@spot[0..4,5])) {
                dbg("PCPROT: Duplicate Spot ignored\n") if isdbg('chanerr');
                return;
        }

        # add it
        Spot::add(@spot);

        #
        # @spot at this point contains:-
        # freq, spotted call, time, text, spotter, spotted cc, spotters cc, orig node
        # then  spotted itu, spotted cq, spotters itu, spotters cq
        # you should be able to route on any of these
        #

        # fix up qra locators of known users
        my $user = DXUser->get_current($spot[4]);
        if ($user) {
                my $qra = $user->qra;
                unless ($qra && is_qra($qra)) {
                        my $lat = $user->lat;
                        my $long = $user->long;
                        if (defined $lat && defined $long) {
                                $user->qra(DXBearing::lltoqra($lat, $long));
                                $user->put;
                        }
                }

                # send a remote command to a distant cluster if it is visible and there is no
                # qra locator and we havn't done it for a month.

                unless ($user->qra) {
                        my $node;
                        my $to = $user->homenode;
                        my $last = $user->lastoper || 0;
                        if ($send_opernam && $to && $to ne $main::mycall && $main::systime > $last + $DXUser::lastoperinterval && ($node = Route::Node::get($to)) ) {
                                my $cmd = "forward/opernam $spot[4]";
                                # send the rcmd but we aren't interested in the replies...
                                my $dxchan = $node->dxchan;
                                if ($dxchan && $dxchan->is_clx) {
                                        route(undef, $to, pc84($main::mycall, $to, $main::mycall, $cmd));
                                } else {
                                        route(undef, $to, pc34($main::mycall, $to, $cmd));
                                }
                                if ($to ne $_[7]) {
                                        $to = $_[7];
                                        $node = Route::Node::get($to);
                                        if ($node) {
                                                $dxchan = $node->dxchan;
                                                if ($dxchan && $dxchan->is_clx) {
                                                        route(undef, $to, pc84($main::mycall, $to, $main::mycall, $cmd));
                                                } else {
                                                        route(undef, $to, pc34($main::mycall, $to, $cmd));
                                                }
                                        }
                                }
                                $user->lastoper($main::systime);
                                $user->put;
                        }
                }
        }

        # local processing
        if (defined &Local::spot) {
                my $r;
                eval {
                        $r = Local::spot($self, @spot);
                };
                return if $r;
        }

        # DON'T be silly and send on PC26s!
        return if $pcno == 26;

        # send out the filtered spots
        send_dx_spot($self, $line, @spot) if @spot;
}

# announces
sub handle_12
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;

        # announce duplicate checking
        $_[3] =~ s/^\s+//;                      # remove leading blanks

        if ($censorpc) {
                my @bad;
                if (@bad = BadWords::check($_[3])) {
                        dbg("PCPROT: Bad words: @bad, dropped") if isdbg('chanerr');
                        return;
                }
        }

        # if this is a 'nodx' node then ignore it
        if ($badnode->in($_[5])) {
                dbg("PCPROT: Bad Node, dropped") if isdbg('chanerr');
                return;
        }

        # if this is a 'bad spotter' user then ignore it
        my $nossid = $_[1];
        $nossid =~ s/-\d+$//;
        if ($badspotter->in($nossid)) {
                dbg("PCPROT: Bad Spotter, dropped") if isdbg('chanerr');
                return;
        }


        my $dxchan;

        if ((($dxchan = DXChannel::get($_[2])) && $dxchan->is_user) || $_[4] =~ /^[\#\w.]+$/){
                $self->send_chat(0, $line, @_[1..6]);
        } elsif ($_[2] eq '*' || $_[2] eq $main::mycall) {

                # remember a route
#               RouteDB::update($_[5], $self->{call});
#               RouteDB::update($_[1], $_[5]);

                # ignore something that looks like a chat line coming in with sysop
                # flag - this is a kludge...
                if ($_[3] =~ /^\#\d+ / && $_[4] eq '*') {
                        dbg('PCPROT: Probable chat rewrite, dropped') if isdbg('chanerr');
                        return;
                }

                # here's a bit of fun, convert incoming ann with a callsign in the first word
                # or one saying 'to <call>' to a talk if we can route to the recipient
                if ($ann_to_talk) {
                        my $call = AnnTalk::is_talk_candidate($_[1], $_[3]);
                        if ($call) {
                                my $ref = Route::get($call);
                                if ($ref) {
                                        $dxchan = $ref->dxchan;
                                        $dxchan->talk($_[1], $call, undef, $_[3], $_[5]) if $dxchan != $self;
                                        return;
                                }
                        }
                }

                # send it
                $self->send_announce(0, $line, @_[1..6]);
        } else {
                $self->route($_[2], $line);
        }

        # local processing
        if (defined &Local::ann) {
                my $r;
                eval {
                        $r = Local::ann($self, $line, @_[1..6]);
                };
                return if $r;
        }
}

sub handle_15
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;

        if (eph_dup($line, $eph_pc15_restime)) {
                return;
        } else {
                unless ($self->{isolate}) {
                        DXChannel::broadcast_nodes($line, $self) if $line =~ /\^H\d+\^?~?$/; # send it to everyone but me
                }
        }
}

# incoming user
sub handle_16
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;

        # general checks
        my $dxchan;
        my $ncall = $_[1];
        my $newline = "PC16^";

        # dos I want users from this channel?
        unless ($self->user->wantpc16) {
                dbg("PCPROT: don't send users to $self->{call}") if isdbg('chanerr');
                return;
        }

        # is it me?
        if ($ncall eq $main::mycall) {
                dbg("PCPROT: trying to alter config on this node from outside!") if isdbg('chanerr');
                return;
        }

        my $h;
        $h = 1 if DXChannel::get($ncall);
        RouteDB::update($ncall, $self->{call}, $h);
        if ($h && $self->{call} ne $ncall) {
                dbg("PCPROT: trying to update a local node, ignored") if isdbg('chanerr');
                return;
        }

        if (eph_dup($line)) {
                return;
        }

        # isolate now means only accept stuff from this call only
        if ($self->{isolate} && $ncall ne $self->{call}) {
                dbg("PCPROT: $self->{call} isolated, $ncall ignored") if isdbg('chanerr');
                return;
        }

        my $parent = Route::Node::get($ncall);

        if ($parent) {
                $dxchan = $parent->dxchan;
                if ($dxchan && $dxchan ne $self) {
                        dbg("PCPROT: PC16 from $self->{call} trying to alter locally connected $ncall, ignored!") if isdbg('chanerr');
                        return;
                }

                # input filter if required
                return unless $self->in_filter_route($parent);
        } else {
                $parent = Route::Node->new($ncall);
        }

        unless ($h) {
                if ($parent->via_pc92) {
                        dbg("PCPROT: non-local node controlled by PC92, ignored") if isdbg('chanerr');
                        return;
                }
        }

        my $i;
        my @rout;
        for ($i = 2; $i < $#_; $i++) {
                my ($call, $conf, $here) = $_[$i] =~ /^(\S+) (\S) (\d)/o;
                next unless $call && $conf && defined $here && is_callsign($call);
                next if $call eq $main::mycall;

                eph_del_regex("^PC17\\^$call\\^$ncall");

                $conf = $conf eq '*';

                # reject this if we think it is a node already
                my $r = Route::Node::get($call);
                my $u = DXUser->get_current($call) unless $r;
                if ($r || ($u && $u->is_node)) {
                        dbg("PCPROT: $call is a node") if isdbg('chanerr');
                        next;
                }

                $r = Route::User::get($call);
                my $flags = Route::here($here)|Route::conf($conf);

                if ($r) {
                        my $au = $r->addparent($parent);
                        if ($r->flags != $flags) {
                                $r->flags($flags);
                                $au = $r;
                        }
                        push @rout, $r if $h && $au;
                } else {
                        my @ans = $parent->add_user($call, $flags);
                        push @rout, @ans if $h && @ans;
                }

                # add this station to the user database, if required
                my $user = DXUser->get_current($ncall);
                $user = DXUser->new($call) unless $user;
                $user->homenode($parent->call) if !$user->homenode;
                $user->node($parent->call);
                $user->lastin($main::systime) unless DXChannel::get($call);
                $user->put;

                # send info to all logged in thingies
                $self->tell_login('loginu', "$ncall: $call") if $user->is_local_node;
                $self->tell_buddies('loginb', $call, $ncall);
        }
        if (@rout) {
                $self->route_pc16($origin, $line, $parent, @rout) if @rout;
#               $self->route_pc92a($main::mycall, undef, $parent, @rout) if $h && $self->{state} eq 'normal';
        }
}

# remove a user
sub handle_17
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;
        my $dxchan;
        my $ncall = $_[2];
        my $ucall = $_[1];

        eph_del_regex("^PC16\\^$ncall.*$ucall");

        # do I want users from this channel?
        unless ($self->user->wantpc16) {
                dbg("PCPROT: don't send users to $self->{call}") if isdbg('chanerr');
                return;
        }

        if ($ncall eq $main::mycall) {
                dbg("PCPROT: trying to alter config on this node from outside!") if isdbg('chanerr');
                return;
        }

        # isolate now means only accept stuff from this call only
        if ($self->{isolate} && $ncall ne $self->{call}) {
                dbg("PCPROT: $self->{call} isolated, $ncall ignored") if isdbg('chanerr');
                return;
        }

        RouteDB::delete($ncall, $self->{call});

        my $uref = Route::User::get($ucall);
        unless ($uref) {
                dbg("PCPROT: Route::User $ucall not in config") if isdbg('chanerr');
                return;
        }
        my $parent = Route::Node::get($ncall);
        unless ($parent) {
                dbg("PCPROT: Route::Node $ncall not in config") if isdbg('chanerr');
                return;
        }

        $dxchan = DXChannel::get($ncall);
        if ($dxchan && $dxchan ne $self) {
                dbg("PCPROT: PC17 from $self->{call} trying to alter locally connected $ncall, ignored!") if isdbg('chanerr');
                return;
        }

        unless ($dxchan) {
                if ($parent->via_pc92) {
                        dbg("PCPROT: non-local node controlled by PC92, ignored") if isdbg('chanerr');
                        return;
                }
        }

        if (DXChannel::get($ucall)) {
                dbg("PCPROT: trying do disconnect local user, ignored") if isdbg('chanerr');
                return;
        }

        # input filter if required and then remove user if present
#               return unless $self->in_filter_route($parent);
        $parent->del_user($uref);

        # send info to all logged in thingies
        my $user = DXUser->get_current($ncall);
        $self->tell_login('logoutu', "$ncall: $ucall") if $user && $user->is_local_node;
        $self->tell_buddies('logoutb', $ucall, $ncall);

        if (eph_dup($line)) {
                return;
        }

        $self->route_pc17($origin, $line, $parent, $uref);
#       $self->route_pc92d($main::mycall, undef, $parent, $uref) if $dxchan;
}

# link request
sub handle_18
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;
        $self->state('init');

        my $parent = Route::Node::get($self->{call});

        # record the type and version offered
        if (my ($version) = $_[1] =~ /DXSpider Version: (\d+\.\d+)/) {
                $self->{version} = 53 + $version;
                $self->user->version(53 + $version);
                $parent->version(0 + $version);
                my ($build) = $_[1] =~ /Build: (\d+(?:\.\d+)?)/;
                $self->{build} = 0 + $build;
                $self->user->build(0 + $build);
                $parent->build(0 + $build);
                dbg("DXSpider version $version build $build");
                unless ($self->is_spider) {
                        dbg("Change U " . $self->user->sort . " C $self->{sort} -> S");
                        $self->user->sort('S');
                        $self->user->put;
                        $self->sort('S');
                }
#               $self->{handle_xml}++ if DXXml::available() && $_[1] =~ /\bxml/;
        } else {
                dbg("Unknown software");
                $self->version(50.0);
                $self->version($_[2] / 100) if $_[2] && $_[2] =~ /^\d+$/;
                $self->user->version($self->version);
        }

        if ($_[1] =~ /\bpc9x/) {
                if ($self->{isolate}) {
                        dbg("pc9x recognised, but $self->{call} is isolated, using old protocol");
                } elsif (!$self->user->wantpc9x) {
                        dbg("pc9x explicitly switched off on $self->{call}, using old protocol");
                } else {
                        $self->{do_pc9x} = 1;
                        dbg("Do px9x set on $self->{call}");
                }
        }

        # first clear out any nodes on this dxchannel
        my @rout = $parent->del_nodes;
        $self->route_pc21($origin, $line, @rout, $parent) if @rout;
        $self->send_local_config();
        $self->send(pc20());
}

sub check_add_node
{
        my $call = shift;

        # add this station to the user database, if required (don't remove SSID from nodes)
        my $user = DXUser->get_current($call);
        if (!$user) {
                $user = DXUser->new($call);
                $user->priv(1);         # I have relented and defaulted nodes
                $user->lockout(1);
                $user->homenode($call);
                $user->node($call);
        }
        $user->sort('A') unless $user->is_node;
        return $user;
}

# incoming cluster list
sub handle_19
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;

        my $i;
        my $newline = "PC19^";

        # new routing list
        my (@rout, @pc92out);

        # first get the INTERFACE node
        my $parent = Route::Node::get($self->{call});
        unless ($parent) {
                dbg("PCPROT: my parent $self->{call} has disappeared");
                $self->disconnect;
                return;
        }

        my $h;

        # parse the PC19
        #
        # We are making a major change from now on. We are only going to accept
        # PC19s from directly connected nodes.  This means that we are probably
        # going to throw away most of the data that we are being sent.
        #
        # The justification for this is that most of it is wrong or out of date
        # anyway.
        #
        # From now on we are only going to believe PC92 data and locally connected
        # non-pc92 nodes.
        #
        for ($i = 1; $i < $#_-1; $i += 4) {
                my $here = $_[$i];
                my $call = uc $_[$i+1];
                my $conf = $_[$i+2];
                my $ver = $_[$i+3];
                next unless defined $here && defined $conf && is_callsign($call);

                eph_del_regex("^PC(?:21\\^$call|17\\^[^\\^]+\\^$call)");

                # check for sane parameters
                #                               $ver = 5000 if $ver eq '0000';
                next unless $ver && $ver =~ /^\d+$/;
                next if $ver < 5000;    # only works with version 5 software
                next if length $call < 3; # min 3 letter callsigns
                next if $call eq $main::mycall;

                # check that this PC19 isn't trying to alter the wrong dxchan
                $h = 0;
                my $dxchan = DXChannel::get($call);
                if ($dxchan) {
                        if ($dxchan == $self) {
                                $h = 1;
                        } else {
                                dbg("PCPROT: PC19 from $self->{call} trying to alter wrong locally connected $call, ignored!") if isdbg('chanerr');
                                next;
                        }
                }

                # isolate now means only accept stuff from this call only
                if ($self->{isolate} && $call ne $self->{call}) {
                        dbg("PCPROT: $self->{call} isolated, $call ignored") if isdbg('chanerr');
                        next;
                }

                my $user = check_add_node($call);

#               if (eph_dup($genline)) {
#                       dbg("PCPROT: dup PC19 for $call detected") if isdbg('chanerr');
#                       next;
#               }

                RouteDB::update($call, $self->{call}, $dxchan ? 1 : undef);

                unless ($h) {
                        if ($parent->via_pc92) {
                                dbg("PCPROT: non-local node controlled by PC92, ignored") if isdbg('chanerr');
                                next;
                        }
                }

                my $r = Route::Node::get($call);
                my $flags = Route::here($here)|Route::conf($conf);

                # modify the routing table if it is in it, otherwise store it in the pc19list for now
                if ($r) {
                        my $ar;
                        if ($call ne $parent->call) {
                                if ($self->in_filter_route($r)) {
                                        $ar = $parent->add($call, $ver, $flags);
#                                       push @rout, $ar if $ar;
                                } else {
                                        next;
                                }
                        }
                        if ($r->version ne $ver || $r->flags != $flags) {
                                $r->version($ver);
                                $r->flags($flags);
                        }
                        push @rout, $r;
                } else {
                        if ($call eq $self->{call} || $user->wantroutepc19) {
                                my $new = Route->new($call); # throw away
                                if ($self->in_filter_route($new)) {
                                        my $ar = $parent->add($call, $ver, $flags);
                                        $user->wantroutepc19(1) unless defined $user->wantroutepc19;
                                        push @rout, $ar if $ar;
                                        push @pc92out, $r if $h;
                                } else {
                                        next;
                                }
                        }
                }

                # unbusy and stop and outgoing mail (ie if somehow we receive another PC19 without a disconnect)
                my $mref = DXMsg::get_busy($call);
                $mref->stop_msg($call) if $mref;

                $user->lastin($main::systime) unless DXChannel::get($call);
                $user->put;
        }

        # we are not automatically sending out PC19s, we send out a composite PC21,PC19 instead
        # but remember there will only be one (pair) these because any extras will be
        # thrown away.
        if (@rout) {
#               $self->route_pc21($self->{call}, $line, @rout);
                $self->route_pc19($self->{call}, $line, @rout);
        }
        if (@pc92out && !$pc92_slug_changes) {
                $self->route_pc92a($main::mycall, $line, $main::routeroot, @pc92out) if $self->{state} eq 'normal';
        }
}

# send local configuration
sub handle_20
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;

        if ($self->{do_pc9x} && $self->{state} ne 'init92') {
                $self->send("Reseting to oldstyle routing because login call not sent in any pc92");
                $self->{do_pc9x} = 0;
        }
        $self->send_local_config;
        $self->send(pc22());
        $self->state('normal');
        $self->{lastping} = 0;
        $self->route_pc92a($main::mycall, undef, $main::routeroot, Route::Node::get($self->{call}));
}

# delete a cluster from the list
#
# This should never occur for directly connected nodes.
#
sub handle_21
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;
        my $call = uc $_[1];

        eph_del_regex("^PC1[679].*$call");

        # if I get a PC21 from the same callsign as self then ignore it
        if ($call eq $self->{call}) {
                dbg("PCPROT: self referencing PC21 from $self->{call}");
                return;
        }

        # for the above reason and also because of the check for PC21s coming
        # in for self->call from outside being ignored further down
        # we don't need any isolation code here, because we will never
        # act on a PC21 with self->call in it.

        RouteDB::delete($call, $self->{call});

        my $parent = Route::Node::get($self->{call});
        unless ($parent) {
                dbg("PCPROT: my parent $self->{call} has disappeared");
                $self->disconnect;
                return;
        }

        my @rout;

        if ($call ne $main::mycall) { # don't allow malicious buggers to disconnect me!
                my $node = Route::Node::get($call);
                if ($node) {

                        if ($node->via_pc92) {
                                dbg("PCPROT: controlled by PC92, ignored") if isdbg('chanerr');
                                return;
                        }

                        my $dxchan = DXChannel::get($call);
                        if ($dxchan && $dxchan != $self) {
                                dbg("PCPROT: PC21 from $self->{call} trying to alter locally connected $call, ignored!") if isdbg('chanerr');
                                return;
                        }

                        # input filter it
                        return unless $self->in_filter_route($node);

                        # routing objects, force a PC21 if it is local
                        push @rout, $node->del($parent);
                        push @rout, $call if $dxchan && @rout == 0;
                }
        } else {
                dbg("PCPROT: I WILL _NOT_ be disconnected!") if isdbg('chanerr');
                return;
        }

        if (eph_dup($line)) {
                return;
        }

        if (@rout) {
                $self->route_pc21($origin, $line, @rout);
#               $self->route_pc92d($main::mycall, $line, $main::routeroot, @rout);
        }
}


sub handle_22
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;

        if ($self->{do_pc9x}) {
                if ($self->{state} ne 'init92') {
                        $self->send("Reseting to oldstyle routing because login call not sent in any pc92");
                        $self->{do_pc9x} = 0;
                }
        }
        $self->{lastping} = 0;
        $self->state('normal');
        $self->route_pc92a($main::mycall, undef, $main::routeroot, Route::Node::get($self->{call}));
}

# WWV info
sub handle_23
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;

        # route foreign' pc27s
        if ($pcno == 27) {
                if ($_[8] ne $main::mycall) {
                        $self->route($_[8], $line);
                        return;
                }
        }


        # do some de-duping
        my $d = cltounix($_[1], sprintf("%02d18Z", $_[2]));
        my $sfi = unpad($_[3]);
        my $k = unpad($_[4]);
        my $i = unpad($_[5]);
        my ($r) = $_[6] =~ /R=(\d+)/;
        $r = 0 unless $r;
        if (($pcno == 23 && $d < $main::systime - $pc23_max_age) || $d > $main::systime + 1500 || $_[2] < 0 || $_[2] > 23) {
                dbg("PCPROT: WWV Date ($_[1] $_[2]) out of range") if isdbg('chanerr');
                return;
        }

        # global wwv filtering on INPUT
        my @dxcc = ((Prefix::cty_data($_[7]))[0..2], (Prefix::cty_data($_[8]))[0..2]);
        if ($self->{inwwvfilter}) {
                my ($filter, $hops) = $self->{inwwvfilter}->it(@_[7,8], $origin, @dxcc);
                unless ($filter) {
                        dbg("PCPROT: Rejected by input wwv filter") if isdbg('chanerr');
                        return;
                }
        }
        $_[7] =~ s/-\d+$//o;            # remove spotter's ssid
        if (Geomag::dup($d,$sfi,$k,$i,$_[6],$_[7])) {
                dbg("PCPROT: Dup WWV Spot ignored\n") if isdbg('chanerr');
                return;
        }

        # note this only takes the first one it gets
        Geomag::update($d, $_[2], $sfi, $k, $i, @_[6..8], $r);

        if (defined &Local::wwv) {
                my $rep;
                eval {
                        $rep = Local::wwv($self, $_[1], $_[2], $sfi, $k, $i, @_[6..8], $r);
                };
                return if $rep;
        }

        # DON'T be silly and send on PC27s!
        return if $pcno == 27;

        # broadcast to the eager world
        send_wwv_spot($self, $line, $d, $_[2], $sfi, $k, $i, @_[6..8]);
}

# set here status
sub handle_24
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;
        my $call = uc $_[1];
        my ($nref, $uref);
        $nref = Route::Node::get($call);
        $uref = Route::User::get($call);
        return unless $nref || $uref; # if we don't know where they are, it's pointless sending it on

        if (eph_dup($line)) {
                return;
        }

        $nref->here($_[2]) if $nref;
        $uref->here($_[2]) if $uref;
        my $ref = $nref || $uref;
        return unless $self->in_filter_route($ref);

        $self->route_pc24($origin, $line, $ref, $_[3]);
}

# merge request
sub handle_25
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;
        if ($_[1] ne $main::mycall) {
                $self->route($_[1], $line);
                return;
        }
        if ($_[2] eq $main::mycall) {
                dbg("PCPROT: Trying to merge to myself, ignored") if isdbg('chanerr');
                return;
        }

        Log('DXProt', "Merge request for $_[3] spots and $_[4] WWV from $_[2]");

        # spots
        if ($_[3] > 0) {
                my @in = reverse Spot::search(1, undef, undef, 0, $_[3]);
                my $in;
                foreach $in (@in) {
                        $self->send(pc26(@{$in}[0..4], $_[2]));
                }
        }

        # wwv
        if ($_[4] > 0) {
                my @in = reverse Geomag::search(0, $_[4], time, 1);
                my $in;
                foreach $in (@in) {
                        $self->send(pc27(@{$in}[0..5], $_[2]));
                }
        }
}

sub handle_26 {goto &handle_11}
sub handle_27 {goto &handle_23}

# mail/file handling
sub handle_28
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;
        if ($_[1] eq $main::mycall) {
                no strict 'refs';
                my $sub = "DXMsg::handle_$pcno";
                &$sub($self, @_);
        } else {
                $self->route($_[1], $line) unless $self->is_clx;
        }
}

sub handle_29 {goto &handle_28}
sub handle_30 {goto &handle_28}
sub handle_31 {goto &handle_28}
sub handle_32 {goto &handle_28}
sub handle_33 {goto &handle_28}

sub handle_34
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;
        if (eph_dup($line, $eph_pc34_restime)) {
                return;
        } else {
                $self->process_rcmd($_[1], $_[2], $_[2], $_[3]);
        }
}

# remote command replies
sub handle_35
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;
        eph_del_regex("^PC35\\^$_[2]\\^$_[1]\\^");
        $self->process_rcmd_reply($_[1], $_[2], $_[1], $_[3]);
}

sub handle_36 {goto &handle_34}

# database stuff
sub handle_37
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;
        if ($_[1] eq $main::mycall) {
                no strict 'refs';
                my $sub = "DXDb::handle_$pcno";
                &$sub($self, @_);
        } else {
                $self->route($_[1], $line) unless $self->is_clx;
        }
}

# node connected list from neighbour
sub handle_38
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;
}

# incoming disconnect
sub handle_39
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;
        if ($_[1] eq $self->{call}) {
                $self->disconnect(1);
        } else {
                dbg("PCPROT: came in on wrong channel") if isdbg('chanerr');
        }
}

sub handle_40 {goto &handle_28}

# user info
sub handle_41
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;
        my $call = $_[1];
        my $sort = $_[2];
        my $val = $_[3];

        my $l = "PC41^$call^$sort";
        if (eph_dup($l, $eph_info_restime)) {
                return;
        }

        # input filter if required
        #                       my $ref = Route::get($call) || Route->new($call);
        #                       return unless $self->in_filter_route($ref);

        if ($val eq $sort || $val =~ /^\s*$/) {
                dbg('PCPROT: invalid value') if isdbg('chanerr');
                return;
        }

        # add this station to the user database, if required
        my $user = DXUser->get_current($call);
        $user = DXUser->new($call) unless $user;

        if ($sort == 1) {
                if (($val =~ /spotter/i || $val =~ /self/i) && $user->name && $user->name ne $val) {
                        dbg("PCPROT: invalid name") if isdbg('chanerr');
                        if ($main::mycall eq 'GB7DJK' || $main::mycall eq 'GB7BAA' || $main::mycall eq 'WR3D') {
                                DXChannel::broadcast_nodes(pc41($_[1], 1, $user->name)); # send it to everyone including me
                        }
                        return;
                }
                $user->name($val);
        } elsif ($sort == 2) {
                $user->qth($val);
        } elsif ($sort == 3) {
                if (is_latlong($val)) {
                        my ($lat, $long) = DXBearing::stoll($val);
                        $user->lat($lat) if $lat;
                        $user->long($long) if $long;
                        $user->qra(DXBearing::lltoqra($lat, $long)) unless $user->qra;
                } else {
                        dbg('PCPROT: not a valid lat/long') if isdbg('chanerr');
                        return;
                }
        } elsif ($sort == 4) {
                $user->homenode($val);
        } elsif ($sort == 5) {
                if (is_qra(uc $val)) {
                        my ($lat, $long) = DXBearing::qratoll(uc $val);
                        $user->lat($lat) if $lat && !$user->lat;
                        $user->long($long) if $long && !$user->long;
                        $user->qra(uc $val);
                } else {
                        dbg('PCPROT: not a valid QRA locator') if isdbg('chanerr');
                        return;
                }
        }
        $user->lastoper($main::systime); # to cut down on excessive for/opers being generated
        $user->put;

        unless ($self->{isolate}) {
                DXChannel::broadcast_nodes($line, $self); # send it to everyone but me
        }

        #  perhaps this IS what we want after all
        #                       $self->route_pc41($ref, $call, $sort, $val, $_[4]);
}

sub handle_42 {goto &handle_28}


# database
sub handle_44 {goto &handle_37}
sub handle_45 {goto &handle_37}
sub handle_46 {goto &handle_37}
sub handle_47 {goto &handle_37}
sub handle_48 {goto &handle_37}

# message and database
sub handle_49
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;

        if (eph_dup($line)) {
                return;
        }

        if ($_[1] eq $main::mycall) {
                DXMsg::handle_49($self, @_);
        } else {
                $self->route($_[1], $line) unless $self->is_clx;
        }
}

# keep alive/user list
sub handle_50
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;

        return if (eph_dup($line));

        my $call = $_[1];

        RouteDB::update($call, $self->{call});

        my $node = Route::Node::get($call);
        if ($node) {
                return unless $node->call eq $self->{call};
                $node->usercount($_[2]) unless $node->users;
                $node->reset_obs;

                # input filter if required
#               return unless $self->in_filter_route($node);

                unless ($self->{isolate}) {
                        DXChannel::broadcast_nodes($line, $self); # send it to everyone but me
                }
#               $self->route_pc50($origin, $line, $node, $_[2], $_[3]) unless eph_dup($line);
        }
}

# incoming ping requests/answers
sub handle_51
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;
        my $to = $_[1];
        my $from = $_[2];
        my $flag = $_[3];


        # is it for us?
        if ($to eq $main::mycall) {
                if ($flag == 1) {
                        $self->send(pc51($from, $to, '0'));
                } else {
                        DXXml::Ping::handle_ping_reply($self, $from);
                }
        } else {

                RouteDB::update($from, $self->{call});

                if (eph_dup($line)) {
                        return;
                }
                # route down an appropriate thingy
                $self->route($to, $line);
        }
}

sub handle_61 { goto &handle_11; }

# dunno but route it
sub handle_75
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;
        my $call = $_[1];
        if ($call ne $main::mycall) {
                $self->route($call, $line);
        }
}

# WCY broadcasts
sub handle_73
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;
        my $call = $_[1];

        # do some de-duping
        my $d = cltounix($call, sprintf("%02d18Z", $_[2]));
        if (($pcno == 23 && $d < $main::systime - $pc23_max_age) || $d > $main::systime + 1500 || $_[2] < 0 || $_[2] > 23) {
                dbg("PCPROT: WCY Date ($call $_[2]) out of range") if isdbg('chanerr');
                return;
        }
        @_ = map { unpad($_) } @_;
        if (WCY::dup($d)) {
                dbg("PCPROT: Dup WCY Spot ignored\n") if isdbg('chanerr');
                return;
        }

        my $wcy = WCY::update($d, @_[2..12]);

        if (defined &Local::wcy) {
                my $rep;
                eval {
                        $rep = Local::wcy($self, @_[1..12]);
                };
                return if $rep;
        }

        # broadcast to the eager world
        send_wcy_spot($self, $line, $d, @_[2..12]);
}

# remote commands (incoming)
sub handle_84
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;
        $self->process_rcmd($_[1], $_[2], $_[3], $_[4]);
}

# remote command replies
sub handle_85
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;
        $self->process_rcmd_reply($_[1], $_[2], $_[3], $_[4]);
}

# decode a pc92 call: flag call : version : build
sub _decode_pc92_call
{
        my $icall = shift;
        my @part = split /:/, $icall;
        my ($flag, $call) = unpack "A A*", $part[0];
        unless (defined $flag && $flag ge '0' && $flag le '7') {
                dbg("PCPROT: $icall no flag byte (0-7) at front of call, ignored") if isdbg('chanerr');
                return ();
        }
        unless ($call && is_callsign($call)) {
                dbg("PCPROT: $icall no recognisable callsign, ignored") if isdbg('chanerr');
                return ();
        }
        my $is_node = $flag & 4;
        my $is_extnode = $flag & 2;
        my $here = $flag & 1;
        return ($call, $is_node, $is_extnode, $here, $part[1], $part[2]);
}

# decode a pc92 call: flag call : version : build
sub _encode_pc92_call
{
        my $ref = shift;

        # plain call or value
        return $ref unless ref $ref;

        my $ext = shift;
        my $flag = 0;
        my $call = $ref->call;
        my $extra = '';
        $flag |= $ref->here ? 1 : 0;
        if ($ref->isa('Route::Node') || $ref->isa('DXProt')) {
                $flag |= 4;
                my $dxchan = DXChannel::get($call);
                $flag |= 2 if $call ne $main::mycall && $dxchan && !$dxchan->{do_pc9x};
                if ($ext) {
                        if ($ref->version) {
                                my $version = $ref->version || 1.0;
                                $version =  $version * 100 + 5300 if $version < 50;
                                $extra .= ":" . $version;
                        }
                }
        }
        return "$flag$call$extra";
}

my %things_add;
my %things_del;

sub _add_thingy
{
        my $parent = shift;
        my $s = shift;
        my ($call, $is_node, $is_extnode, $here, $version, $build) = @$s;
        my @rout;

        if ($call) {
                if ($is_node) {
                        dbg("ROUTE: added node $call to " . $parent->call) if isdbg('routelow');
                        @rout = $parent->add($call, $version, Route::here($here));
                } else {
                        dbg("ROUTE: added user $call to " . $parent->call) if isdbg('routelow');
                        @rout = $parent->add_user($call, Route::here($here));
                }
                if ($pc92_slug_changes && $parent == $main::routeroot) {
                        $things_add{$call} = Route::get($call);
                        delete $things_del{$call};
                }
        }
        return @rout;
}

sub _del_thingy
{
        my $parent = shift;
        my $s = shift;
        my ($call, $is_node, $is_extnode, $here, $version, $build) = @$s;
        my @rout;
        if ($call) {
                my $ref;
                if ($is_node) {
                        $ref = Route::Node::get($call);
                        dbg("ROUTE: deleting node $call from " . $parent->call) if isdbg('routelow');
                        @rout = $ref->del($parent) if $ref;
                } else {
                        $ref = Route::User::get($call);
                        dbg("ROUTE: deleting user $call from " . $parent->call) if isdbg('routelow');
                        @rout = $parent->del_user($ref) if $ref;
                }
                if ($pc92_slug_changes && $parent == $main::routeroot) {
                        $things_del{$call} = $ref unless exists $things_add{$call};
                        delete $things_add{$call};
                }
        }
        return @rout;
}

# this will only happen if we are slugging changes and
# there are some changes to be sent, it will create an add or a delete
# or both
sub gen_pc92_changes
{
        my @add = values %things_add;
        my @del = values %things_del;
        return (\@add, \@del);
}

sub clear_pc92_changes
{
        %things_add = %things_del = ();
        $last_pc92_slug = $main::systime;
}

my $_last_time;
my $_last_occurs;
my $_last_pc9x_id;

sub last_pc9x_id
{
        return $_last_pc9x_id;
}

sub gen_pc9x_t
{
        if (!$_last_time || $_last_time != $main::systime) {
                $_last_time = $main::systime;
                $_last_occurs = 0;
                return $_last_pc9x_id = $_last_time - $main::systime_daystart;
        } else {
                $_last_occurs++;
                return $_last_pc9x_id = sprintf "%d.%02d", $_last_time - $main::systime_daystart, $_last_occurs;
        }
}

sub check_pc9x_t
{
        my $call = shift;
        my $t = shift;
        my $pc = shift;
        my $create = shift;

        # check that the time is between 0 >= $t < 86400
        unless ($t >= 0 && $t < 86400) {
                dbg("PCPROT: time invalid t: $t, ignored") if isdbg('chanerr');
                return undef;
        }

        # check that the time of this pc9x is within tolerance (default 15 mins either way)
        my $now = $main::systime - $main::systime_daystart ;
        my $diff = abs($now - $t);
        unless ($diff < $pc9x_time_tolerance || 86400 - $diff < $pc9x_time_tolerance) {
                my $c = ref $call ? $call->call : $call;
                dbg("PC9XERR: $c time out of range t: $t now: $now diff: $diff > $pc9x_time_tolerance, ignored") if isdbg('chan');
                return undef;
        }

        my $parent = ref $call ? $call : Route::Node::get($call);
        if ($parent) {
                # we only do this for external calls whose routing table
                # record come and go. The reference for mycall is permanent
                # and not that frequently used, it also never times out, so
                # the id on it is completely unreliable. Besides, only commands
                # originating on this box will go through this code...
                if ($parent->call ne $main::mycall) {
                        my $lastid = $parent->lastid;
                        if (defined $lastid) {
                                if ($t < $lastid) {
                                        # note that this is where we determine whether this pc9x has come in yesterday
                                        # but is still greater (modulo 86400) than the lastid or is simply an old
                                        # duplicate sentence. To determine this we need to do some module 86400
                                        # arithmetic. High numbers mean that this is an old duplicate sentence,
                                        # low numbers that it is a new sentence.
                                        #
                                        # Typically you will see yesterday being taken on $t = 84, $lastid = 86235
                                        # and old dupes with $t = 234, $lastid = 256 (which give answers 249 and
                                        # 86378 respectively in the calculation below).
                                        #
                                        if ($t+86400-$lastid > $pc9x_past_age) {
                                                dbg("PCPROT: dup id on $t <= lastid $lastid, ignored") if isdbg('chanerr') || isdbg('pc92dedupe');
                                                return undef;
                                        }
                                } elsif ($t == $lastid) {
                                        dbg("PCPROT: dup id on $t == lastid $lastid, ignored") if isdbg('chanerr') || isdbg('pc92dedupe');
                                        return undef;
                                } else {
                                        # check that if we have a low number in lastid that yesterday's numbers
                                        # (likely in the 85000+ area) don't override them, thus causing flip flopping
                                        if ($lastid+86400-$t < $pc9x_past_age) {
                                                dbg("PCPROT: dup id on $t in yesterday, lastid $lastid, ignored") if isdbg('chanerr') || isdbg('pc92dedupe');
                                                return undef;
                                        }
                                }
                        }
                }
        } elsif ($create) {
                $parent = Route::Node->new($call);
        } else {
                dbg("PCPROT: $call does not exist, ignored") if isdbg('pc92dedupe');
                return undef;
        }
        if (isdbg('pc92dedupe')) {
                my $exists = exists $parent->{lastid}; # naughty, naughty :-)
                my $val = $parent->{lastid};
                my $s = $exists ? (defined $val ? $val : 'exists/undef') : 'undef';
                dbg("PCPROT: $call pc92 id lastid $s -> $t");
        }
        $parent->lastid($t);

        return $parent;
}

sub pc92_handle_first_slot
{
        my $self = shift;
        my $slot = shift;
        my $parent = shift;
        my $t = shift;
        my $oparent = $parent;

        my @radd;

        my ($call, $is_node, $is_extnode, $here, $version, $build) = @$slot;
        if ($call && $is_node) {
                if ($call eq $main::mycall) {
                        dbg("PCPROT: $call looped back onto $main::mycall, ignored") if isdbg('chanerr');
                        return;
                }
                # this is only accepted from my "self".
                # this also kills configs from PC92 nodes with external PC19 nodes that are also
                # locally connected. Local nodes always take precedence. But we remember the lastid
                # to try to reduce the number of dupe PC92s for this external node.
                if (DXChannel::get($call) && $call ne $self->{call}) {
                        $parent = check_pc9x_t($call, $t, 92); # this will update the lastid time
                        dbg("PCPROT: locally connected node $call from other another node $self->{call}, ignored") if isdbg('chanerr');
                        return;
                }
                if ($is_extnode) {
                        # reparent to external node (note that we must have received a 'C' or 'A' record
                        # from the true parent node for this external before we get one for the this node
                        unless ($parent = Route::Node::get($call)) {
                                if ($is_extnode && $oparent) {
                                        @radd = _add_thingy($oparent, $slot);
                                        $parent = $radd[0];
                                } else {
                                        dbg("PCPROT: no previous C or A for this external node received, ignored") if isdbg('chanerr');
                                        return;
                                }
                        }
                        $parent = check_pc9x_t($call, $t, 92) || return;
                        $parent->via_pc92(1);
                        $parent->PC92C_dxchan($self->{call});
                }
        } else {
                dbg("PCPROT: must be \$mycall or external node as first entry, ignored") if isdbg('chanerr');
                return;
        }
        $parent->here(Route::here($here));
        $parent->version($version || $pc19_version) if $version;
        $parent->build($build) if $build;
        $parent->PC92C_dxchan($self->{call}) unless $self->{call} eq $parent->call;
        return ($parent, @radd);
}

# DXSpider routing entries
sub handle_92
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;

        my (@radd, @rdel);

        my $pcall = $_[1];
        my $t = $_[2];
        my $sort = $_[3];

        # this catches loops of A/Ds
#       if (eph_dup($line, $pc9x_dupe_age)) {
#               return;
#       }

        if ($pcall eq $main::mycall) {
                dbg("PCPROT: looped back, ignored") if isdbg('chanerr');
                return;
        }

        if ($pcall eq $self->{call} && $self->{state} eq 'init') {
                if ($self->{isolate}) {
                        dbg("PC9x received, but $pcall is isolated, ignored");
                        return;
                } elsif (!$self->user->wantpc9x) {
                        dbg("PC9x explicitly switched off on $pcall, ignored");
                        return;
                } else {
                        $self->state('init92');
                        $self->{do_pc9x} = 1;
                        dbg("Do pc9x set on $pcall");
                }
        }
        unless ($self->{do_pc9x}) {
                dbg("PCPROT: PC9x come in from non-PC9x node, ignored") if isdbg('chanerr');
                return;
        }

        # don't create routing entries for D records that don't already exist
        # this is what causes all those PC92 loops!
        my $parent = check_pc9x_t($pcall, $t, 92, $sort ne 'D') || return;
        my $oparent = $parent;

        $parent->do_pc9x(1);
        $parent->via_pc92(1);

        if ($sort eq 'F' || $sort eq 'R') {

                # this is the route finding section
                # here is where the consequences of the 'find' command
                # are dealt with

                my $from = $_[4];
                my $target = $_[5];

                if ($sort eq 'F') {
                        my $flag;
                        my $ref;
                        my $dxchan;
                        if ($ref = DXChannel::get($target)) {
                                $flag = 1;              # we are directly connected
                        } else {
                                $ref = Route::get($target);
                                $dxchan = $ref->dxchan;
                                $flag = 2;
                        }
                        if ($ref && $flag && $dxchan) {
                                $self->send(pc92r($from, $target, $flag, int($dxchan->{pingave}*1000)));
                                return;
                        }
                } elsif ($sort eq 'R') {
                        if (my $dxchan = DXChannel::get($from)) {
                                handle_pc92_find_reply($dxchan, $pcall, $from, $target, @_[6,7]);
                        } else {
                                my $ref = Route::get($from);
                                if ($ref) {
                                        my @dxchan = grep {$_->do_pc9x} $ref->alldxchan;
                                        if (@dxchan) {
                                                $_->send($line) for @dxchan;
                                        } else {
                                                dbg("PCPROT: no return route, ignored") if isdbg('chanerr')
                                        }
                                } else {
                                        dbg("PCPROT: no return route, ignored") if isdbg('chanerr')
                                }
                        }
                        return;
                }

        } elsif ($sort eq 'K') {
                $pc92Kin += length $line if $sort eq 'K';

                # remember the last channel we arrived on
                $parent->PC92C_dxchan($self->{call}) unless $self->{call} eq $parent->call;

                my @ent = _decode_pc92_call($_[4]);

                if (@ent) {
                        my $add;

                        ($parent, $add) = $self->pc92_handle_first_slot(\@ent, $parent, $t);
                        return unless $parent; # dupe

                        push @radd, $add if $add;
                        $parent->reset_obs;
                        $parent->version($ent[4]) if $ent[4];
                        $parent->build($ent[5]) if $ent[5];

                        dbg("ROUTE: reset obscount on $parent->{call} now " . $parent->obscount) if isdbg('obscount');
                }
        } elsif ($sort eq 'A' || $sort eq 'D' || $sort eq 'C') {

                $pc92Ain += length $line if $sort eq 'A';
                $pc92Cin += length $line if $sort eq 'C';
                $pc92Din += length $line if $sort eq 'D';

                # remember the last channel we arrived on
                $parent->PC92C_dxchan($self->{call}) unless $self->{call} eq $parent->call;

                # this is the main route section
                # here is where all the routes are created and destroyed

                # cope with missing duplicate node calls in the first slot
                my $me = $_[4] || '';
                $me ||= _encode_pc92_call($parent) unless $me ;

                my @ent = map {my @a = _decode_pc92_call($_); @a ? \@a : ()} grep {$_ && /^[0-7]/} $me, @_[5 .. $#_];

                if (@ent) {

                        # look at the first one which will always be a node of some sort
                        # except in the case of 'A' or 'D' in which the $pcall is used
                        # otherwise use the node call and update any information
                        # that needs to be done.
                        my $add;

                        ($parent, $add) = $self->pc92_handle_first_slot($ent[0], $parent, $t);
                        return unless $parent; # dupe

                        shift @ent;
                        push @radd, $add if $add;
                }

                # do a pass through removing any references to either locally connected nodes or mycall
                my @nent;
                for (@ent) {
                        next unless $_ && @$_;
                        if ($_->[0] eq $main::mycall || DXChannel::get($_->[0])) {
                                dbg("PCPROT: $_->[0] refers to locally connected node, ignored") if isdbg('chanerr');
                                next;
                        }
                        push @nent, $_;
                }

                if ($sort eq 'A') {
                        for (@nent) {
                                push @radd, _add_thingy($parent, $_);
                        }
                } elsif ($sort eq 'D') {
                        for (@nent) {
                                push @rdel, _del_thingy($parent, $_);
                        }
                } elsif ($sort eq 'C') {
                        my (@nodes, @users);

                        # we reset obscounts on config records as well as K records
                        $parent->reset_obs;
                        dbg("ROUTE: reset obscount on $parent->{call} now " . $parent->obscount) if isdbg('obscount');

                        #
                        foreach my $r (@nent) {
                                #                       my ($call, $is_node, $is_extnode, $here, $version, $build) = _decode_pc92_call($_);
                                if ($r->[0]) {
                                        if ($r->[1]) {
                                                push @nodes, $r->[0];
                                        } else {
                                                push @users, $r->[0];
                                        }
                                } else {
                                        dbg("PCPROT: pc92 call entry '$_' not decoded, ignored") if isdbg('chanerr');
                                }
                        }

                        my ($dnodes, $dusers, $nnodes, $nusers) = $parent->calc_config_changes(\@nodes, \@users);

                        # add users here
                        foreach my $r (@nent) {
                                my $call = $r->[0];
                                if ($call) {
                                        push @radd,_add_thingy($parent, $r) if grep $call eq $_, (@$nnodes, @$nusers);
                                }
                        }
                        # del users here
                        foreach my $r (@$dnodes) {
                                push @rdel,_del_thingy($parent, [$r, 1]);
                        }
                        foreach my $r (@$dusers) {
                                push @rdel,_del_thingy($parent, [$r, 0]);
                        }

                        # remember this last PC92C for rebroadcast on demand
                        $parent->last_PC92C($line);
                } else {
                        dbg("PCPROT: unknown action '$sort', ignored") if isdbg('chanerr');
                        return;
                }

                foreach my $r (@rdel) {
                        next unless $r;

                        $self->route_pc21($pcall, undef, $r) if $r->isa('Route::Node');
                        $self->route_pc17($pcall, undef, $parent, $r) if $r->isa('Route::User');
                }
                my @pc19 = grep { $_ && $_->isa('Route::Node') } @radd;
                my @pc16 = grep { $_ && $_->isa('Route::User') } @radd;
                unshift @pc19, $parent if $self->{state} eq 'init92' && $oparent == $parent;
                $self->route_pc19($pcall, undef, @pc19) if @pc19;
                $self->route_pc16($pcall, undef, $parent, @pc16) if @pc16;
        }

        # broadcast it if we get here
        $self->broadcast_route_pc9x($pcall, undef, $line, 0);
}


sub handle_93
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;

#       $self->{do_pc9x} ||= 1;

        my $pcall = $_[1];                      # this is now checked earlier

        # remember that we are converting PC10->PC93 and self will be $main::me if it
        # comes from us
        unless ($self->{do_pc9x}) {
                dbg("PCPROT: PC9x come in from non-PC9x node, ignored") if isdbg('chanerr');
                return;
        }

        my $t = $_[2];
        my $parent = check_pc9x_t($pcall, $t, 93, 1) || return;

        my $to = uc $_[3];
        my $from = uc $_[4];
        my $via = uc $_[5];
        my $text = $_[6];
        my $onode = uc $_[7];
        $onode = $pcall if @_ <= 8;

        # this is catch loops caused by bad software ...
        if (eph_dup("PC93|$from|$text|$onode", $pc10_dupe_age)) {
                return;
        }

        # will we allow it at all?
        if ($censorpc) {
                my @bad;
                if (@bad = BadWords::check($text)) {
                        dbg("PCPROT: Bad words: @bad, dropped") if isdbg('chanerr');
                        return;
                }
        }

        # if this is a 'bad spotter' user then ignore it
        my $nossid = $from;
        $nossid =~ s/-\d+$//;
        if ($badspotter->in($nossid)) {
                dbg("PCPROT: Bad Spotter, dropped") if isdbg('chanerr');
                return;
        }

        # ignore PC93 coming in from outside this node with a target of local
        if ($to eq 'LOCAL' && $self != $main::me) {
                dbg("PCPROT: incoming LOCAL chat not from local node, ignored") if isdbg('chanerr');
                return;
        }

        # if it is routeable then then treat it like a talk
        my $ref = Route::get($to);
        if ($ref) {
                # local talks
                my $dxchan;
                $dxchan = DXChannel::get($main::myalias) if $to eq $main::mycall;
                $dxchan = DXChannel::get($to) unless $dxchan;
                # check it...
                if ($dxchan) {
                        if (ref $dxchan && $dxchan->isa('DXChannel')) {
                                if ($dxchan->is_user) {
                                        $dxchan->talk($from, $to, $via, $text, $onode);
                                        return;
                                }
                        } else {
                                dbg("ERROR: $to -> $dxchan is not a DXChannel! (local talk)");
                        }
                }

                # convert to PC10 talks where appropriate
                # just go for the "best" one for now (rather than broadcast)
                $dxchan = $ref->dxchan;

                # check it...
                if (ref $dxchan && $dxchan->isa('DXChannel')) {
                        if ($dxchan->{do_pc9x}) {
                                $dxchan->send($line);
                        } else {
                                $dxchan->talk($from, $to, $via, $text, $onode);
                        }
                } else {
                        dbg("ERROR: $to -> $dxchan is not a DXChannel! (convert to pc10)");
                }
                return;

        } elsif ($to eq '*' || $to eq 'SYSOP' || $to eq 'WX') {
                # announces
                my $sysop = $to eq 'SYSOP' ? '*' : ' ';
                my $wx = $to eq 'WX' ? '1' : '0';
                my $local = $via eq 'LOCAL' ? '*' : $via;

                $self->send_announce(1, pc12($from, $text, $local, $sysop, $wx, $pcall), $from, $local, $text, $sysop, $pcall, $wx, $via eq 'LOCAL' ? $via : undef);
                return if $via eq 'LOCAL';
        } elsif (!is_callsign($to) && $text =~ /^#\d+ /) {
                # chat messages to non-pc9x nodes
                $self->send_chat(1, pc12($from, $text, undef, $to, undef, $pcall), $from, '*', $text, $to, $pcall, '0');
        }

        # broadcast this chat sentence everywhere unless it is targetted to 'LOCAL'
        $self->broadcast_route_pc9x($pcall, undef, $line, 0) unless $to eq 'LOCAL' || $via eq 'LOCAL';
}

# if get here then rebroadcast the thing with its Hop count decremented (if
# there is one). If it has a hop count and it decrements to zero then don't
# rebroadcast it.
#
# NOTE - don't arrive here UNLESS YOU WANT this lump of protocol to be
#        REBROADCAST!!!!
#

sub handle_default
{
        my $self = shift;
        my $pcno = shift;
        my $line = shift;
        my $origin = shift;

        unless (eph_dup($line)) {
                if ($pcno >= 90) {
                        my $pcall = $_[1];
                        unless (is_callsign($pcall)) {
                                dbg("PCPROT: invalid callsign string '$_[1]', ignored") if isdbg('chanerr');
                                return;
                        }
                        my $t = $_[2];
                        my $parent = check_pc9x_t($pcall, $t, $pcno, 1) || return;
                        $self->broadcast_route_pc9x($pcall, undef, $line, 0);
                } else {
                        unless ($self->{isolate}) {
                                DXChannel::broadcast_nodes($line, $self) if $line =~ /\^H\d+\^?~?$/; # send it to everyone but me
                        }
                }
        }
}

1;