#!/usr/bin/perl -w

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 2 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

use strict;
use warnings;
use Getopt::Long qw(GetOptionsFromString);
use Pod::Usage;
use File::Basename;
use File::Spec;
use IO::Handle;
use Time::HiRes("usleep");
use Socket;
use FileHandle;
use IPC::Open2;
use POSIX qw(:errno_h);
use Cwd qw(getcwd abs_path);

# always flush
$| = 1;

my $invocation_dir = getcwd();

chomp(my $gittop = `git rev-parse --show-toplevel 2>/dev/null`);

## Configuration file handling

# Default configuration
$CFG::hypervisor = "";
$CFG::hypervisor_params = "serial";
$CFG::genisoimage = "genisoimage";
$CFG::iprelay_addr = '141.76.48.80:2324'; #'141.76.48.252';
$CFG::qemu = 'qemu';
@CFG::chainloaders = (); #('bin/boot/bender promisc'); # TODO: convert to option
$CFG::pulsar_root = '';	 # TODO: convert to option
$CFG::pulsar_mac = '52-54-00-12-34-56';
%CFG::targets = (
    "tud" => '--server=erwin.inf.tu-dresden.de:~sojka/boot/novaboot --rsync-flags="--chmod=Dg+s,ug+w,o-w,+rX --rsync-path=\"umask 002 && rsync\"" --grub --grub-prefix=(nd)/tftpboot/sojka/novaboot --grub-preamble="timeout 0" --concat --iprelay=141.76.48.80:2324 --scriptmod=s/\\\\bhostserial\\\\b/hostserialpci/g',
    "novabox" => '--server=rtime.felk.cvut.cz:/srv/tftp/novaboot --rsync-flags="--chmod=Dg+s,ug+w,o-w,+rX --rsync-path=\"umask 002 && rsync\"" --pulsar=novaboot --iprelay=147.32.86.92:2324',
    "localhost" => '--scriptmod=s/console=tty[A-Z0-9,]+// --server=/boot/novaboot/$NAME --grub2 --grub-prefix=/boot/novaboot/$NAME --grub2-prolog="  set root=\'(hd0,msdos1)\'"',
    );
$CFG::scons = "scons -j2";

my @qemu_flags = qw(-cpu coreduo -smp 2);
sub read_config($) {
    my ($cfg) = @_;
    {
	package CFG; # Put config data into a separate namespace
	my $rc = do($cfg);

	# Check for errors
	if ($@) {
	    die("ERROR: Failure compiling '$cfg' - $@");
	} elsif (! defined($rc)) {
	    die("ERROR: Failure reading '$cfg' - $!");
	} elsif (! $rc) {
	    die("ERROR: Failure processing '$cfg'");
	}
    }
    print "novaboot: Read $cfg\n";
}

my @cfgs;
{
    # We don't use $0 here, because it points to the novaboot itself and
    # not to the novaboot script. The problem with this approach is that
    # when a script is run as "novaboot <options> <script>" then $ARGV[0]
    # contains the first option. Hence the -f check.
    my $dir = abs_path($invocation_dir . ((-f $ARGV[0]) ? '/'.dirname($ARGV[0]) : ''));
    while (-d $dir && $dir ne "/") {
	push @cfgs, "$dir/.novaboot" if -r "$dir/.novaboot";
	$dir = abs_path($dir."/..");
    }
}
my $cfg = $ENV{'NOVABOOT_CONFIG'};
Getopt::Long::Configure(qw/no_ignore_case pass_through/);
GetOptions ("config|c=s" => \$cfg);
read_config($_) foreach $cfg or reverse @cfgs;

## Command line handling

my ($append, $bender, $builddir, $concat, $config_name_opt, $dhcp_tftp, $dump_opt, $dump_config, $grub_config, $grub_prefix, $grub_preamble, $grub2_prolog, $grub2_config, $help, $iprelay, $iso_image, $man, $no_file_gen, $off_opt, $on_opt, $pulsar, $qemu, $qemu_append, $qemu_flags_cmd, $rom_prefix, $rsync_flags, @scriptmod, $scons, $serial, $server);

$rsync_flags = '';
$rom_prefix = 'rom://';

Getopt::Long::Configure(qw/no_ignore_case no_pass_through/);
my %opt_spec;
%opt_spec = (
    "append|a=s"     => \$append,
    "bender|b"       => \$bender,
    "build-dir=s"    => \$builddir,
    "concat"	     => \$concat,
    "dhcp-tftp|d"    => \$dhcp_tftp,
    "dump"	     => \$dump_opt,
    "dump-config"    => \$dump_config,
    "grub|g:s" 	     => \$grub_config,
    "grub-preamble=s"=> \$grub_preamble,
    "grub-prefix=s"  => \$grub_prefix,
    "grub2:s" 	     => \$grub2_config,
    "grub2-prolog=s" => \$grub2_prolog,
    "iprelay:s"	     => \$iprelay,
    "iso|i:s" 	     => \$iso_image,
    "name=s"	     => \$config_name_opt,
    "no-file-gen"    => \$no_file_gen,
    "off"	     => \$off_opt,
    "on"	     => \$on_opt,
    "pulsar|p:s"     => \$pulsar,
    "qemu|Q=s" 	     => \$qemu,
    "qemu-append:s"  => \$qemu_append,
    "qemu-flags|q=s" => \$qemu_flags_cmd,
    "rsync-flags=s"  => \$rsync_flags,
    "scons:s"	     => \$scons,
    "scriptmod=s"    => \@scriptmod,
    "serial|s:s"     => \$serial,
    "server:s" 	     => \$server,
    "strip-rom"	     => sub { $rom_prefix = ''; },
    "target|t=s"     => sub { my ($opt_name, $opt_value) = @_;
			      exists $CFG::targets{$opt_value} or die("Unknown target '$opt_value' (valid targets are: ".join(", ", sort keys(%CFG::targets)).")");
			      GetOptionsFromString($CFG::targets{$opt_value}, %opt_spec); },
    "h" 	     => \$help,
    "help" 	     => \$man,
    );
GetOptions %opt_spec or pod2usage(2);
pod2usage(1) if $help;
pod2usage(-exitstatus => 0, -verbose => 2) if $man;

### Sanitize configuration

$CFG::iprelay_addr = $ENV{'NOVABOOT_IPRELAY'} if $ENV{'NOVABOOT_IPRELAY'};
if ($iprelay && $iprelay ne "on" && $iprelay ne "off") { $CFG::iprelay_addr = $iprelay; }

if (defined $config_name_opt && scalar(@ARGV) > 1) { die "You cannot use --name with multiple scripts"; }

if ($qemu) { $CFG::qemu = $qemu; }
$qemu_append ||= '';

if ($pulsar) {
    $CFG::pulsar_mac = $pulsar;
}

if ($scons) { $CFG::scons = $scons; }

### Dump sanitized configuration (if requested)

if ($dump_config) {
    use Data::Dumper;
    $Data::Dumper::Indent=0;
    print "# This file is in perl syntax.\n";
    foreach my $key(sort(keys(%CFG::))) { # See "Symbol Tables" in perlmod(1)
	if (defined ${$CFG::{$key}}) { print Data::Dumper->Dump([${$CFG::{$key}}], ["*$key"]); }
	if (        @{$CFG::{$key}}) { print Data::Dumper->Dump([\@{$CFG::{$key}}], ["*$key"]); }
	if (        %{$CFG::{$key}}) { print Data::Dumper->Dump([\%{$CFG::{$key}}], ["*$key"]); }
	print "\n";
    }
    print "1;\n";
    exit;
}

if (defined $serial) {
    $serial ||= "/dev/ttyUSB0";
}

if (defined $grub_config) {
    $grub_config ||= "menu.lst";
}

if (defined $grub2_config) {
    $grub2_config ||= "grub.cfg";
}

if ($on_opt) { $iprelay="on"; }
if ($off_opt) { $iprelay="off"; }

## Parse the novaboot script(s)
my @scripts;
my $file;
my $line;
my $EOF;
my $last_fn = '';
my ($modules, $variables, $generated, $continuation);
while (<>) {
    if ($ARGV ne $last_fn) { # New script
	die "Missing EOF in $last_fn" if $file;
	die "Unfinished line in $last_fn" if $line;
	$last_fn = $ARGV;
	push @scripts, { 'filename' => $ARGV,
			 'modules' => $modules = [],
			 'variables' => $variables = {},
			 'generated' => $generated = []};

    }
    chomp();
    next if /^#/ || /^\s*$/;	# Skip comments and empty lines

    foreach my $mod(@scriptmod) { eval $mod; }

    print "$_\n" if $dump_opt;

    if (/^([A-Z_]+)=(.*)$/) {	# Internal variable
	$$variables{$1} = $2;
	next;
    }
    if (/^([^ ]*)(.*?)[[:space:]]*<<([^ ]*)$/) { # Heredoc start
	push @$modules, "$1$2";
	$file = [];
	push @$generated, {filename => $1, content => $file};
	$EOF = $3;
	next;
    }
    if ($file && $_ eq $EOF) {	# Heredoc end
	undef $file;
	next;
    }
    if ($file) {		# Heredoc content
	push @{$file}, "$_\n";
	next;
    }
    $_ =~ s/^[[:space:]]*// if ($continuation);
    if (/\\$/) {		# Line continuation
	$line .= substr($_, 0, length($_)-1);
	$continuation = 1;
	next;
    }
    $continuation = 0;
    $line .= $_;
    $line .= " $append" if ($append && scalar(@$modules) == 0);

    if ($line =~ /^([^ ]*)(.*?)[[:space:]]*< ?(.*)$/) { # Command substitution
	push @$modules, "$1$2";
	push @$generated, {filename => $1, command => $3};
	$line = '';
	next;
    }
    push @$modules, $line;
    $line = '';
}
#use Data::Dumper;
#print Dumper(\@scripts);

exit if $dump_opt;

## Helper functions

sub generate_configs($$$) {
    my ($base, $generated, $filename) = @_;
    if ($base) { $base = "$base/"; };
    foreach my $g(@$generated) {
      if (exists $$g{content}) {
	my $config = $$g{content};
	my $fn = $$g{filename};
	open(my $f, '>', $fn) || die("$fn: $!");
	map { s|\brom://([^ ]*)|$rom_prefix$base$1|g; print $f "$_"; } @{$config};
	close($f);
	print "novaboot: Created $fn\n";
      } elsif (exists $$g{command} && ! $no_file_gen) {
	$ENV{SRCDIR} = dirname(File::Spec->rel2abs( $filename, $invocation_dir ));
	system_verbose("( $$g{command} ) > $$g{filename}");
      }
    }
}

sub generate_grub_config($$$$;$)
{
    my ($filename, $title, $base, $modules_ref, $preamble) = @_;
    if ($base) { $base = "$base/"; };
    open(my $fg, '>', $filename) or die "$filename: $!";
    print $fg "$preamble\n" if $preamble;
    my $endmark = ($serial || defined $iprelay) ? ';' : '';
    print $fg "title $title$endmark\n" if $title;
    #print $fg "root $base\n"; # root doesn't really work for (nd)
    my $first = 1;
    foreach (@$modules_ref) {
	if ($first) {
	    $first = 0;
	    my ($kbin, $kcmd) = split(' ', $_, 2);
	    $kcmd = '' if !defined $kcmd;
	    print $fg "kernel ${base}$kbin $kcmd\n";
	} else {
	    s|\brom://([^ ]*)|$rom_prefix$base$1|g; # Translate rom:// files - needed for vdisk parameter of sigma0
	    print $fg "module $base$_\n";
	}
    }
    close($fg);
    print("novaboot: Created $CFG::builddir/$filename\n");
    return $filename;
}

sub generate_grub2_config($$$$;$$)
{
    my ($filename, $title, $base, $modules_ref, $preamble, $prolog) = @_;
    if ($base && substr($base,-1,1) ne '/') { $base = "$base/"; };
    open(my $fg, '>', $filename) or die "$filename: $!";
    print $fg "$preamble\n" if $preamble;
    my $endmark = ($serial || defined $iprelay) ? ';' : '';
    $title ||= 'novaboot';
    print $fg "menuentry $title$endmark {\n";
    print $fg "$prolog\n" if $prolog;
    my $first = 1;
    foreach (@$modules_ref) {
	if ($first) {
	    $first = 0;
	    my ($kbin, $kcmd) = split(' ', $_, 2);
	    $kcmd = '' if !defined $kcmd;
	    print $fg "  multiboot ${base}$kbin $kcmd\n";
	} else {
	    my @args = split;
	    # GRUB2 doesn't pass filename in multiboot info so we have to duplicate it here
	    $_ = join(' ', ($args[0], @args));
	    s|\brom://|$rom_prefix|g; # We do not need to translate path for GRUB2
	    print $fg "  module $base$_\n";
	}
    }
    print $fg "}\n";
    close($fg);
    print("novaboot: Created $CFG::builddir/$filename\n");
    return $filename;
}

sub generate_pulsar_config($$)
{
    my ($filename, $modules_ref) = @_;
    open(my $fg, '>', $filename) or die "$filename: $!";
    print $fg "root $CFG::pulsar_root\n" if $CFG::pulsar_root;
    my $first = 1;
    my ($kbin, $kcmd);
    foreach (@$modules_ref) {
	if ($first) {
	    $first = 0;
	    ($kbin, $kcmd) = split(' ', $_, 2);
	    $kcmd = '' if !defined $kcmd;
	} else {
	    my @args = split;
	    s|\brom://|$rom_prefix|g;
	    print $fg "load $_\n";
	}
    }
    # Put kernel as last - this is needed for booting Linux and has no influence on non-Linux OSes
    print $fg "exec $kbin $kcmd\n";
    close($fg);
    print("novaboot: Created $CFG::builddir/$filename\n");
    return $filename;
}

sub exec_verbose(@)
{
    print "novaboot: Running: ".join(' ', map("'$_'", @_))."\n";
    exec(@_);
}

sub system_verbose($)
{
    my $cmd = shift;
    print "novaboot: Running: $cmd\n";
    my $ret = system($cmd);
    if ($ret & 0x007f) { die("Command terminated by a signal"); }
    if ($ret & 0xff00) {die("Command exit with non-zero exit code"); }
    if ($ret) { die("Command failure $ret"); }
}

## WvTest handline

if (exists $variables->{WVDESC}) {
    print "Testing \"$variables->{WVDESC}\" in $last_fn:\n";
} elsif ($last_fn =~ /\.wv$/) {
    print "Testing \"all\" in $last_fn:\n";
}

## Handle reset and power on/off

my $IPRELAY;
if (defined $iprelay) {
    $CFG::iprelay_addr =~ /([.0-9]+)(:([0-9]+))?/;
    my $addr = $1;
    my $port = $3 || 23;
    my $paddr   = sockaddr_in($port, inet_aton($addr));
    my $proto   = getprotobyname('tcp');
    socket($IPRELAY, PF_INET, SOCK_STREAM, $proto)  || die "socket: $!";
    print "novaboot: Connecting to IP relay... ";
    connect($IPRELAY, $paddr)    || die "connect: $!";
    print "done\n";
    $IPRELAY->autoflush(1);

    while (1) {
	print $IPRELAY "\xFF\xF6";
	alarm(20);
	local $SIG{ALRM} = sub { die "Relay AYT timeout"; };
	my $ayt_reponse = "";
	my $read = sysread($IPRELAY, $ayt_reponse, 100);
	alarm(0);

	chomp($ayt_reponse);
	print "$ayt_reponse\n";
	if ($ayt_reponse =~ /<iprelayd: not connected/) {
	    sleep(10);
	    next;
	}
	last;
    }

    sub relaycmd($$) {
	my ($relay, $onoff) = @_;
	die unless ($relay == 1 || $relay == 2);

	my $cmd = ($relay == 1 ? 0x5 : 0x6) | ($onoff ? 0x20 : 0x10);
	return "\xFF\xFA\x2C\x32".chr($cmd)."\xFF\xF0";
    }

    sub relayconf($$) {
	my ($relay, $onoff) = @_;
	die unless ($relay == 1 || $relay == 2);
	my $cmd = ($relay == 1 ? 0xdf : 0xbf) | ($onoff ? 0x00 : 0xff);
	return "\xFF\xFA\x2C\x97".chr($cmd)."\xFF\xF0";
    }

    sub relay($$;$) {
	my ($relay, $onoff, $can_giveup) = @_;
	my $confirmation = '';
	print $IPRELAY relaycmd($relay, $onoff);

	# We use non-blocking I/O and polling here because for some
	# reason read() on blocking FD returns only after all
	# requested data is available. If we get during the first
	# read() only a part of confirmation, we may get the rest
	# after the system boots and print someting, which may be too
	# long.
	$IPRELAY->blocking(0);

	alarm(20); # Timeout in seconds
	my $giveup = 0;
        local $SIG{ALRM} = sub {
	    if ($can_giveup) { print("Relay confirmation timeout - ignoring\n"); $giveup = 1;}
	    else {die "Relay confirmation timeout";}
	};
	my $index;
	while (($index=index($confirmation, relayconf($relay, $onoff))) < 0 && !$giveup) {
	    my $read = read($IPRELAY, $confirmation, 70, length($confirmation));
	    if (!defined($read)) {
		die("IP relay: $!") unless $! == EAGAIN;
		usleep(10000);
		next;
	    }
	    #use MIME::QuotedPrint;
	    #print "confirmation = ".encode_qp($confirmation)."\n";
	}
	alarm(0);
	$IPRELAY->blocking(1);
    }
}

if ($iprelay && ($iprelay eq "on" || $iprelay eq "off")) {
     relay(1, 1); # Press power button
    if ($iprelay eq "on") {
	usleep(100000);		# Short press
    } else {
	usleep(6000000);	# Long press to switch off
    }
    print $IPRELAY relay(1, 0);
    exit;
}

## Figure out the location of builddir and chdir() there
if ($builddir) {
    $CFG::builddir = $builddir;
} else {
    if (! defined $CFG::builddir) {
	$CFG::builddir = ( $gittop || $ENV{'HOME'}."/nul" ) . "/build";
	if (! -d $CFG::builddir) {
	    $CFG::builddir = $ENV{SRCDIR} = dirname(File::Spec->rel2abs( ${$scripts[0]}{filename}, $invocation_dir ));
	}
    }
}

chdir($CFG::builddir) or die "Can't change directory to $CFG::builddir: $!";
print "novaboot: Entering directory `$CFG::builddir'\n";

## File generation phase
my (%files_iso, $menu_iso, $config_name, $filename);

foreach my $script (@scripts) {
    $filename = $$script{filename};
    $modules = $$script{modules};
    $generated = $$script{generated};
    $variables = $$script{variables};

    ($config_name = $filename) =~ s#.*/##;
    $config_name = $config_name_opt if (defined $config_name_opt);

    my $kernel;
    if (exists $variables->{KERNEL}) {
	$kernel = $variables->{KERNEL};
    } else {
	if ($CFG::hypervisor) {
	    $kernel = $CFG::hypervisor . " ";
	    if (exists $variables->{HYPERVISOR_PARAMS}) {
		$kernel .= $variables->{HYPERVISOR_PARAMS};
	    } else {
		$kernel .= $CFG::hypervisor_params;
	    }
	}
    }
    @$modules = ($kernel, @$modules) if $kernel;
    @$modules = (@CFG::chainloaders, @$modules);
    @$modules = ("bin/boot/bender", @$modules) if ($bender || defined $ENV{'NOVABOOT_BENDER'});

    my $prefix;
    ($prefix = $grub_prefix) =~ s/\$NAME/$config_name/ if defined $grub_prefix;
    $prefix ||= $CFG::builddir;
    # TODO: use $grub_prefix as first parameter if some switch is given
    generate_configs('', $generated, $filename);

### Generate bootloader configuration files
    my $pulsar_config;
    my @bootloader_configs;
    push @bootloader_configs, generate_grub_config($grub_config, $config_name, $prefix, $modules, $grub_preamble) if (defined $grub_config);
    push @bootloader_configs, generate_grub2_config($grub2_config, $config_name, $prefix, $modules, $grub_preamble, $grub2_prolog) if (defined $grub2_config);
    push @bootloader_configs, generate_pulsar_config($pulsar_config = "config-$CFG::pulsar_mac", $modules) if (defined $pulsar);

### Run scons
    if (defined $scons) {
	my @files = map({ ($file) = m/([^ ]*)/; $file; } @$modules);
	# Filter-out generated files
	my @to_build = grep({ my $file = $_; !scalar(grep($file eq $$_{filename}, @$generated)) } @files);
	system_verbose($CFG::scons." ".join(" ", @to_build));
    }

### Copy files (using rsync)
    if (defined $server) {
	(my $real_server = $server) =~ s/\$NAME/$config_name/;

	my ($hostname, $path) = split(":", $real_server, 2);
	if (! defined $path) {
	    $path = $hostname;
	    $hostname = "";
	}
	my $files = join(" ", map({ ($file) = m/([^ ]*)/; $file; } ( @$modules, @bootloader_configs)));
	map({ my $file = (split)[0]; die "$file: $!" if ! -f $file; } @$modules);
	my $istty = -t STDOUT && ($ENV{'TERM'} || 'dumb') ne 'dumb';
	my $progress = $istty ? "--progress" : "";
	system_verbose("rsync $progress -RLp $rsync_flags $files $real_server");
	if ($server =~ m|/\$NAME$| && $concat) {
	    my $cmd = join("; ", map { "( cd $path/.. && cat */$_ > $_ )" } @bootloader_configs);
	    system_verbose($hostname ? "ssh $hostname '$cmd'" : $cmd);
	}
    }

### Prepare ISO image generation
    if (defined $iso_image) {
	generate_configs("(cd)", $generated, $filename);
	my $menu;
	generate_grub_config(\$menu, $config_name, "(cd)", $modules);
	$menu_iso .= "$menu\n";
	map { ($file,undef) = split; $files_iso{$file} = 1; } @$modules;
    }
}

## Generate ISO image
if (defined $iso_image) {
    open(my $fh, ">menu-iso.lst");
    print $fh "timeout 5\n\n$menu_iso";
    close($fh);
    my $files = "boot/grub/menu.lst=menu-iso.lst " . join(" ", map("$_=$_", keys(%files_iso)));
    $iso_image ||= "$config_name.iso";
    system_verbose("$CFG::genisoimage -R -b stage2_eltorito -no-emul-boot -boot-load-size 4 -boot-info-table -hide-rr-moved -J -joliet-long -o $iso_image -graft-points bin/boot/grub/ $files");
    print("ISO image created: $CFG::builddir/$iso_image\n");
}

## Boot the system using various methods and send serial output to stdout

if (scalar(@scripts) > 1 && ( defined $dhcp_tftp || defined $serial || defined $iprelay)) {
    die "You cannot do this with multiple scripts simultaneously";
}

if ($variables->{WVTEST_TIMEOUT}) {
    print "wvtest: timeout ", $variables->{WVTEST_TIMEOUT}, "\n";
}

sub trim($) {
    my ($str) = @_;
    $str =~ s/^\s+|\s+$//g;
    return $str
}

### Qemu

if (!(defined $dhcp_tftp || defined $serial || defined $iprelay || defined $server || defined $iso_image)) {
    # Qemu
    if (!$qemu && $variables->{QEMU}) {
	@qemu_flags = split(" ", $variables->{QEMU});
	$CFG::qemu = shift(@qemu_flags);
    }

    @qemu_flags = split(/ +/, trim($variables->{QEMU_FLAGS})) if exists $variables->{QEMU_FLAGS};
    @qemu_flags = split(/ +/, trim($qemu_flags_cmd)) if $qemu_flags_cmd;
    push(@qemu_flags, split(/ +/, trim($qemu_append)));

    if (defined $iso_image) {
	# Boot NOVA with grub (and test the iso image)
	push(@qemu_flags, ('-cdrom', "$config_name.iso"));
    } else {
	# Boot NOVA without GRUB

	# Non-patched qemu doesn't like commas, but NUL can live with pluses instead of commans
	foreach (@$modules) {s/,/+/g;}
	generate_configs("", $generated, $filename);

	my ($kbin, $kcmd) = split(' ', shift(@$modules), 2);
	$kcmd = '' if !defined $kcmd;
	my $dtb;
	@$modules = map { if (/\.dtb$/) { $dtb=$_; (); } else { $_ } } @$modules;
	my $initrd = join ",", @$modules;

	push(@qemu_flags, ('-kernel', $kbin, '-append', $kcmd));
	push(@qemu_flags, ('-initrd', $initrd)) if $initrd;
	push(@qemu_flags, ('-dtb', $dtb)) if $dtb;
    }
    push(@qemu_flags,  qw(-serial stdio)); # Redirect serial output (for collecting test restuls)
    exec_verbose(($CFG::qemu,  '-name', $config_name, @qemu_flags));
}

### Local DHCPD and TFTPD

my ($dhcpd_pid, $tftpd_pid);

if (defined $dhcp_tftp)
{
    generate_configs("(nd)", $generated, $filename);
    system_verbose('mkdir -p tftpboot');
    generate_grub_config("tftpboot/os-menu.lst", $config_name, "(nd)", \@$modules, "timeout 0");
    open(my $fh, '>', 'dhcpd.conf');
    my $mac = `cat /sys/class/net/eth0/address`;
    chomp $mac;
    print $fh "subnet 10.23.23.0 netmask 255.255.255.0 {
		      range 10.23.23.10 10.23.23.100;
		      filename \"bin/boot/grub/pxegrub.pxe\";
		      next-server 10.23.23.1;
}
host server {
	hardware ethernet $mac;
	fixed-address 10.23.23.1;
}";
    close($fh);
    system_verbose("sudo ip a add 10.23.23.1/24 dev eth0;
	    sudo ip l set dev eth0 up;
	    sudo touch dhcpd.leases");

    $dhcpd_pid = fork();
    if ($dhcpd_pid == 0) {
	# This way, the spawned server are killed when this script is killed.
	exec_verbose("sudo dhcpd -d -cf dhcpd.conf -lf dhcpd.leases -pf dhcpd.pid");
    }
    $tftpd_pid = fork();
    if ($tftpd_pid == 0) {
	exec_verbose("sudo in.tftpd --foreground --secure -v -v -v $CFG::builddir");
    }
    $SIG{TERM} = sub { print "CHILDS KILLED\n"; kill 15, $dhcpd_pid, $tftpd_pid; };
}

### Serial line or IP relay

if ($serial || defined $iprelay) {
    my $CONN;
    if (defined $iprelay) {
	print "novaboot: Reseting the test box... ";
	relay(2, 1, 1); # Reset the machine
	usleep(100000);
	relay(2, 0);
	print "done\n";

	$CONN = $IPRELAY;
    } elsif ($serial) {
	system("stty -F $serial raw -crtscts -onlcr 115200");
	open($CONN, "+<", $serial) || die "open $serial: $!";
	$CONN->autoflush(1);
    }

    # Pass the NOVA output to stdout.
    while (<$CONN>) {
	print;
    }
    kill 15, $dhcpd_pid, $tftpd_pid if ($dhcp_tftp);
    exit;
}

### Wait for dhcpc or tftpd
if (defined $dhcp_tftp) {
    my $pid = wait();
    if ($pid == $dhcpd_pid) { print "dhcpd exited!\n"; }
    elsif ($pid == $tftpd_pid) { print "tftpd exited!\n"; }
    else { print "wait returned: $pid\n"; }
    kill(15, 0); # Kill current process group i.e. all remaining children
}

## Documentation

=head1 NAME

novaboot - A tool for booting various operating systems on various hardware or in qemu

=head1 SYNOPSIS

B<novaboot> [ options ] [--] script...

B<./script> [ options ]

B<novaboot> --help

=head1 DESCRIPTION

This program makes it easier to boot NOVA or other operating system
(OS) in different environments. It reads a so called novaboot script
and uses it either to boot the OS in an emulator (e.g. in qemu) or to
generate the configuration for a specific bootloader and optionally to
copy the necessary binaries and other needed files to proper
locations, perhaps on a remote server. In case the system is actually
booted, its serial output is redirected to standard output if that is
possible.

A typical way of using novaboot is to make the novaboot script
executable and set its first line to I<#!/usr/bin/env novaboot>. Then,
booting a particular OS configuration becomes the same as executing a
local program - the novaboot script.

With C<novaboot> you can:

=over 3

=item 1.

Run an OS in Qemu. This is the default action when no other action is
specified by command line switches. Thus running C<novaboot ./script>
(or C<./script> as described above) will run Qemu and make it boot the
configuration specified in the I<script>.

=item 2.

Create a bootloader configuration file (currently supported
bootloaders are GRUB, GRUB2 and Pulsar) and copy it with all other
files needed for booting to another, perhaps remote, location.

 ./script --server --iprelay

This command copies files to a TFTP server specified in the
configuration file and uses TCP/IP-controlled relay to reset the test
box and receive its serial output.

=item 3.

Run DHCP and TFTP server on developer's machine to PXE-boot NOVA from
it. E.g.

 ./script --dhcp-tftp

When a PXE-bootable machine is connected via Ethernet to developer's
machine, it will boot the configuration described in I<script>.

=item 4.

Create bootable ISO images. E.g.

 novaboot --iso -- script1 script2

The created ISO image will have GRUB bootloader installed on it and
the boot menu will allow selecting between I<script1> and I<script2>
configurations.

=back

=head1 PHASES AND OPTIONS

Novaboot perform its work in several phases. Each phase can be
influenced by several options, certain phases can be skipped. The list
of phases with the corresponding options follows.

=head2 Configuration reading phase

After starting, novaboot reads configuration files. By default, it
searches for files named F<.novaboot> starting from the directory of
the novaboot script (or working directory, see bellow) and continuing
upwards up to the root directory. The configuration files are read in
order from the root directory downwards with latter files overriding
settings from the former ones.

In certain cases, the location of the novaboot script cannot be
determined in this early phase. This happens either when the script is
read from the standard input or when novaboot is invoked explicitly
and options precede the script name, as in the example L</"4."> above.
In this case the current working directory is used as a starting point
for configuration file search.

=over 8

=item -c, --config=<filename>

Use the specified configuration file instead of the default one(s).

=back

=head2 Command line processing phase

=over 8

=item --dump-config

Dump the current configuration to stdout end exits. Useful as an
initial template for a configuration file.

=item -h, --help

Print short (B<-h>) or long (B<--help>) help.

=item -t, --target=<target>

This option serves as a user configurable shortcut for other novaboot
options. The effect of this option is the same as the options stored
in the C<%targets> configuration variable under key I<target>. See
also L</"CONFIGURATION FILE">.

=back

=head2 Script preprocessing phase

This phases allows to modify the parsed novaboot script before it is
used in the later phases.

=over 8

=item -a, --append=<parameters>

Appends a string to the first "filename" line in the novaboot script.
This can be used to append parameters to the kernel's or root task's
command line.

=item -b, --bender

Use F<bender> chainloader. Bender scans the PCI bus for PCI serial
ports and stores the information about them in the BIOS data area for
use by the kernel.

=item --dump

Prints the content of the novaboot script after removing comments and
evaluating all I<--scriptmod> expressions. Exit after reading (and
dumping) the script.

=item --scriptmod=I<perl expression>

When novaboot script is read, I<perl expression> is executed for every
line (in $_ variable). For example, C<novaboot
--scriptmod=s/sigma0/omega6/g> replaces every occurrence of I<sigma0>
in the script with I<omega6>.

When this option is present, it overrides I<$script_modifier> variable
from the configuration file, which has the same effect. If this option
is given multiple times all expressions are evaluated in the command
line order.

=item --strip-rom

Strip I<rom://> prefix from command lines and generated config files.
The I<rom://> prefix is used by NUL. For NRE, it has to be stripped.

=back

=head2 File generation phase

In this phase, files needed for booting are generated in a so called
I<build directory> (see TODO). In most cases configuration for a
bootloader is generated automatically by novaboot. It is also possible
to generate other files using I<heredoc> or I<"<"> syntax in novaboot
scripts. Finally, binaries can be generated in this phases by running
C<scons> or C<make>.

=over 8

=item --build-dir=<directory>

Overrides the default build directory location.

The default build directory location is determined as follows:

If there is a configuration file, the value specified in the
I<$builddir> variable is used. Otherwise, if the current working
directory is inside git work tree and there is F<build> directory at
the top of that tree, it is used. Otherwise, if directory
F<~/nul/build> exists, it is used. Otherwise, it is the directory that
contains the first processed novaboot script.

=item -g, --grub[=I<filename>]

Generates grub bootloader menu file. If the I<filename> is not
specified, F<menu.lst> is used. The I<filename> is relative to the
build directory (see B<--build-dir>).

=item --grub-preamble=I<prefix>

Specifies the I<preable> that is at the beginning of the generated
GRUB or GRUB2 config files. This is useful for specifying GRUB's
timeout.

=item --grub-prefix=I<prefix>

Specifies I<prefix> that is put in front of every file name in GRUB's
F<menu.lst>. The default value is the absolute path to the build directory.

If the I<prefix> contains string $NAME, it will be replaced with the
name of the novaboot script (see also B<--name>).

=item --grub2[=I<filename>]

Generate GRUB2 menuentry in I<filename>. If I<filename> is not
specified F<grub.cfg> is used. The content of the menuentry can be
customized with B<--grub-preable>, B<--grub2-prolog> or
B<--grub_prefix> options.

In order to use the the generated menuentry on your development
machine that uses GRUB2, append the following snippet to
F</etc/grub.d/40_custom> file and regenerate your grub configuration,
i.e. run update-grub on Debian/Ubuntu.

  if [ -f /path/to/nul/build/grub.cfg ]; then
    source /path/to/nul/build/grub.cfg
  fi

=item --grub2-prolog=I<prolog>

Specifies text I<preable> that is put at the begiging of the entry
GRUB2 entry.

=item --name=I<string>

Use the name I<string> instead of the name of the novaboot script.
This name is used for things like a title of grub menu or for the
server directory where the boot files are copied to.

=item --no-file-gen

Do not generate files on the fly (i.e. "<" syntax) except for the
files generated via "<<WORD" syntax.

=item -p, --pulsar[=mac]

Generates pulsar bootloader configuration file whose name is based on
the MAC address specified either on the command line or taken from
I<.novaboot> configuration file.

=back

=head2 File deployment phase

In some setups, it is necessary to copy the files needed for booting
to a particular location, e.g. to a TFTP boot server or to the
F</boot> partition.

=over 8

=item -d, --dhcp-tftp

Turns your workstation into a DHCP and TFTP server so that NOVA
can be booted via PXE BIOS on a test machine directly connected by
a plain Ethernet cable to your workstation.

The DHCP and TFTP servers require root privileges and C<novaboot>
uses C<sudo> command to obtain those. You can put the following to
I</etc/sudoers> to allow running the necessary commands without
asking for password.

 Cmnd_Alias NOVABOOT = /bin/ip a add 10.23.23.1/24 dev eth0, /bin/ip l set dev eth0 up, /usr/sbin/dhcpd -d -cf dhcpd.conf -lf dhcpd.leases -pf dhcpd.pid, /usr/sbin/in.tftpd --foreground --secure -v -v -v *, /usr/bin/touch dhcpd.leases
 your_login ALL=NOPASSWD: NOVABOOT

=item -i, --iso[=filename]

Generates the ISO image that boots NOVA system via GRUB. If no filename
is given, the image is stored under I<NAME>.iso, where I<NAME> is the name
of the novaboot script (see also B<--name>).

=item --server[=[[user@]server:]path]

Copy all files needed for booting to another location (implies B<-g>
unless B<--grub2> is given). The files will be copied (by B<rsync>
tool) to the directory I<path>. If the I<path> contains string $NAME,
it will be replaced with the name of the novaboot script (see also
B<--name>).

=item --concat

If B<--server> is used and its value ends with $NAME, then after
copying the files, a new bootloader configuration file (e.g. menu.lst)
is created at I<path-wo-name>, i.e. the path specified by B<--server>
with $NAME part removed. The content of the file is created by
concatenating all files of the same name from all subdirectories of
I<path-wo-name> found on the "server".

=item --rsync-flags=I<flags>

Specifies which I<flags> are appended to F<rsync> command line when
copying files as a result of I<--server> option.

=item --scons[=scons command]

Runs I<scons> to build files that are not generated by novaboot
itself.

=back

=head2 Target power-on and reset phase

=over 8

=item --iprelay[=addr or cmd]

If no I<cmd> is given, use IP relay to reset the machine and to get
the serial output. The IP address of the relay is given by I<addr>
parameter if specified or by $iprelay_addr variable in the
configuration file.

If I<cmd> is one of "on" or "off", the IP relay is used to press power
button for a short (in case of "on") or long (in case of "off") time.
Then, novaboot exits.

Note: This option is expected to work with HWG-ER02a IP relays.

=item --on, --off

Synonym for --iprelay=on/off.

=item -Q, --qemu=I<qemu-binary>

The name of qemu binary to use. The default is 'qemu'.

=item --qemu-append=I<flags>

Append I<flags> to the default qemu flags (QEMU_FLAGS variable or
C<-cpu coreduo -smp 2>).

=item -q, --qemu-flags=I<flags>

Replace the default qemu flags (QEMU_FLAGS variable or C<-cpu coreduo
-smp 2>) with I<flags> specified here.

=back

=head2 Interaction with the bootloader on the target

See B<--serial>. There will be new options soon.

=head2 Target's output reception phase

=over 8

=item -s, --serial[=device]

Use serial line to control GRUB bootloader and to see the output
serial output of the machine. The default value is F</dev/ttyUSB0>.

=back

See also B<--iprelay>.

=head2 Termination phase

Daemons that were spwned (F<dhcpd> and F<tftpd>) are killed here.

=head1 NOVABOOT SCRIPT SYNTAX

The syntax tries to mimic POSIX shell syntax. The syntax is defined with the following rules.

Lines starting with "#" are ignored.

Lines that end with "\" are concatenated with the following line after
removal of the final "\" and leading whitespace of the following line.

Lines in the form I<VARIABLE=...> (i.e. matching '^[A-Z_]+=' regular
expression) assign values to internal variables. See VARIABLES
section.

Otherwise, the first word on the line represents the filename
(relative to the build directory (see B<--build-dir>) of the module to
load and the remaining words are passed as the command line
parameters.

When the line ends with "<<WORD" then the subsequent lines until the
line containing only WORD are copied literally to the file named on
that line.

When the line ends with "< CMD" the command CMD is executed with
C</bin/sh> and its standard output is stored in the file named on that
line. The SRCDIR variable in CMD's environment is set to the absolute
path of the directory containing the interpreted novaboot script.

Example:
  #!/usr/bin/env novaboot
  WVDESC=Example program
  bin/apps/sigma0.nul S0_DEFAULT script_start:1,1 \
    verbose hostkeyb:0,0x60,1,12,2
  bin/apps/hello.nul
  hello.nulconfig <<EOF
  sigma0::mem:16 name::/s0/log name::/s0/timer name::/s0/fs/rom ||
  rom://bin/apps/hello.nul
  EOF

This example will load three modules: sigma0.nul, hello.nul and
hello.nulconfig. sigma0 gets some command line parameters and
hello.nulconfig file is generated on the fly from the lines between
<<EOF and EOF.

=head2 VARIABLES

The following variables are interpreted in the novaboot script:

=over 8

=item WVDESC

Description of the wvtest-compliant program.

=item WVTEST_TIMEOUT

The timeout in seconds for WvTest harness. If no complete line appears
in the test output within the time specified here, the test fails. It
is necessary to specify this for long running tests that produce no
intermediate output.

=item QEMU

Use a specific qemu binary (can be overriden with B<-Q>) and flags
when booting this script under qemu. If QEMU_FLAGS variable is also
specified flags specified in QEMU variable are replaced by those in
QEMU_FLAGS.

=item QEMU_FLAGS

Use specific qemu flags (can be overriden with B<-q>).

=item HYPERVISOR_PARAMS

Parameters passed to hypervisor. The default value is "serial", unless
overriden in configuration file.

=item KERNEL

The kernel to use instead of NOVA hypervisor specified in the
configuration file. The value should contain the name of the kernel
image as well as its command line parameters. If this variable is
defined and non-empty, the variable HYPERVISOR_PARAMS is not used.

=back

=head1 CONFIGURATION FILE

Novaboot can read its configuration from a file. Configuration file
was necessary in early days of novaboot. Nowadays, an attempt is made
to not use the configuration file because it makes certain novaboot
scripts unusable on systems without (or with different) configuration
file. The only recommended use of the configuration file is to specify
custom_options (see bellow).

If you decide to use the configuration file, it is looked up, by
default, in files named F<.novaboot> as described in L</Configuration
reading phase>. Alternatively, its location can be specified with the
B<-c> switch or with the NOVABOOT_CONFIG environment variable. The
configuration file has perl syntax and should set values of certain
Perl variables. The current configuration can be dumped with the
B<--dump-config> switch. Some configuration variables can be overriden
by environment variables (see below) or by command line switches.

Documentation of some configuration variables follows:

=over 8

=item @chainloaders

Custom chainloaders to load before hypervisor and files specified in
novaboot script. E.g. ('bin/boot/bender promisc', 'bin/boot/zapp').

=item %targets

Hash of shortcuts to be used with the B<--target> option. If the hash
contains, for instance, the following pair of values

 'mybox' => '--server=boot:/tftproot --serial=/dev/ttyUSB0 --grub',

then the following two commands are equivalent:

 ./script --server=boot:/tftproot --serial=/dev/ttyUSB0 --grub
 ./script -t mybox

=back

=head1 ENVIRONMENT VARIABLES

Some options can be specified not only via config file or command line
but also through environment variables. Environment variables override
the values from configuration file and command line parameters
override the environment variables.

=over 8

=item NOVABOOT_CONFIG

Name of the novaboot configuration file to use instead of the default
one(s).

=item NOVABOOT_BENDER

Defining this variable has the same meaning as B<--bender> option.

=item NOVABOOT_IPRELAY

The IP address (and optionally the port) of the IP relay. This
overrides $iprelay_addr variable from the configuration file.

=back

=head1 AUTHORS

Michal Sojka <sojka@os.inf.tu-dresden.de>