#!/usr/bin/perl --        -*-CPerl-*-

use strict;

sub fail
{
    print ::FH ($_ = localtime, " ", @_, "\n");
    close ::FH;
    exit (1);
};

sub current_default_gw
{
    my ($gw, @lines, @matches);

    @lines = `/bin/netstat -nr`;
    @matches = grep (/^0\.0\.0\.0\s+(\S+)\s+/, @lines);
    scalar (@matches) || return;
    $matches[0] =~ /^0\.0\.0\.0\s+(\S+)\s+/;
    $gw = $1;
    return ($gw);
};

sub dhcp_default_gw
{
    my ($if) = shift (@_);
    my ($dhclient_file, $line, $gw, $file_if, @lines);

    $dhclient_file = "/var/lib/dhcp/dhclient-$if.leases";
    $file_if = $if;
    @lines = `/bin/cat $dhclient_file`;
    foreach $line (@lines)
    {
	if ($line =~ /^\s*interface\s+"([^"]+)"/)
	{
	    $file_if = $1;
	}
	elsif (($file_if eq $if) &&
	    ($line =~ /^\s*option\s+routers\s+(\d+\.\d+\.\d+\.\d+)/))
	{
	    $gw = $1;
	};
    };
    defined ($gw) || return;
    return ($gw);
};

sub main
{
    my ($if) = shift (@::ARGV);
    my ($current_gw, $dhcp_gw, $line, @lines);
    my ($ipwdir, @matches);
    my ($must_set) = 0;
    my ($must_unset) = 0;

    ($if =~ /^eth\d+/) ||
      ($if =~ /^wlan\d+/) || return;
    open (::FH, ">>/var/log/ifup-local")
      || die ("Cannot open /var/log/ifup-local: $!");
    defined ($if) || fail ("No argument to ifup-local");

    ##  See if default gw is not set
    $current_gw = current_default_gw();
    defined ($dhcp_gw = dhcp_default_gw ($if)) ||
      fail ("No option routers in /var/lib/dhcp/dhclient-$if.leases");
    if (! defined ($current_gw))
    {
	print ::FH ($_ = localtime, " no current default gw for $if\n");
	$must_set = 1;
    }
    elsif ($current_gw ne $dhcp_gw)
    {
	print ::FH ($_ = localtime, " current gw $current_gw != dhcp gw $dhcp_gw for $if\n");
	$must_set = 1;
	$must_unset = 1;
    };

    if ((! $must_set) && (! $must_unset))
    {
	print ::FH ($_ = localtime,
		    " default gw already set to $dhcp_gw for $if\n");
	return;
    };

    if ($must_unset)
    {
	print ::FH ($_ = localtime, " removing default gw $current_gw for $if\n");
	system ("/sbin/route", "del", "default", "gw", $current_gw);
    };

    if ($must_set)
    {
	print ::FH ($_ = localtime, " adding default gw $dhcp_gw for $if\n");
	system ("/sbin/route", "add", "default", "gw", $dhcp_gw);
    };

    ##  See if this was an ipw wireless startup and if an led exists
    @lines = </sys/bus/pci/drivers/ipw2200/*:*:*.*>;
    if (scalar (@lines) == 1)
    {
	$ipwdir = $lines[0];
	chdir ($ipwdir) || fail ("Cannot chdir to \"$ipwdir\": $!");
	@lines = <net:eth*>;
	if ((scalar (@lines) == 1) &&
	    ($lines[0] eq "net:$if") &&
	    (-e "led"))
	{
	    print ::FH ($_ = localtime, " turning on wireless LED");
	    open (::LED, ">led")
	      && (print ::LED ("1"))
		&& close (::LED);
	};
    };

    close (::FH);
};

main();