#! /usr/bin/perl

# This script gets run after tunnels have been deleted, it removes
# the underlying tunnel link, if all tunnels of that type are gone.

use strict;
use warnings;
use lib "/opt/vyatta/share/perl5";
use Vyatta::Config;

# encapsulations and module names
my %encapsulation = (
    'gre'  => 'ip_gre',
    'ipip' => 'ipip',
    'sit'  => 'sit',
);

# Create map of encapsulations still in use
my $config = new Vyatta::Config;
$config->setLevel("interfaces tunnel");

my %tunnel;
foreach my $tun ( $config->listNodes() ) {
    my $mode = $config->returnValue("$tun encapsulation");
    $tunnel{$mode} = 1;
}

foreach my $type ( keys %encapsulation ) {
    # skip if tunnel is still in use
    next if $tunnel{$type};

    my $module = $encapsulation{$type};
    next unless ( -d "/sys/module/$module" );
    system("sudo /sbin/rmmod $module") == 0
	or warn "rmmod $module failed\n";
}