#!/usr/bin/perl -w
#
# $Id$
# Maintains set of NBIs based on currently-installed kernels
# Network card module sets are taken from /etc/mknbi-set.conf

use strict;
use vars qw($verbosity);

use constant EB_PCI_DEVICE => 1;

# Utility function: calculate output id given a kernel file name and
# space-separated list of modules
sub calc_output_id ($$) {
  my $kernel = shift;
  my $moduleset = shift;
  my $kernel_ver = "";
  ( $kernel_ver ) = ( $kernel =~ /vmlinuz-(.*)$/ );
  ( my $output_id = "$moduleset".( $kernel_ver ? ".$kernel_ver" : "" ) ) =~ tr/,/./;
  return ( $kernel_ver, $output_id );
}

# Utility function: read modules.pcimap-style file
# Add modules to modulesets hash, write out dhcpd.conf fragment
sub read_config_file ($$$$) {
  my $configfile = shift;
  my $modulesets = shift;
  my $dhcpfh = shift;
  my $alwaysuse = shift;

  print "Scanning through $configfile for network modules...\n" if $verbosity >= 1;
  open CF, $configfile or die "Could not open $configfile: $!\n";
  chomp ( my $tempmodule = `mktemp /tmp/mknbi-set.XXXXXX` );
  chomp ( my $cwd = `pwd` ); chdir '/'; # Modprobe searches the current directory...
  print $dhcpfh "    \# Generated from $configfile\n";
  while (<CF>) {
    chomp;
    next if /^[\#;]/ or /^\s*$/;
    ( my $module, undef, my $vendor, my $device ) = /^(\S+)(\s+(\S+)\s+(\S+))?/ ;
    $modulesets->{$module} = 1 if $alwaysuse;
    if ( ! exists $modulesets->{$module} ) {
      # Check to see if module is a network module
      # Only do this the first time we encounter a module
      my @modulepaths = `/sbin/modprobe -l $module.o*` ;
      chomp ( my $modulepath = $modulepaths[0] );
      if ( $modulepath ) {
	if ( $modulepath =~ /.o.gz$/ ) {
	  system ( "zcat $modulepath > $tempmodule" );
	} else {
	  system ( "cp $modulepath $tempmodule" );
	}
	$modulesets->{$module} = 0;
	foreach ( `nm $tempmodule` ) {
	  chomp;
	  $modulesets->{$module} = 1 if /(ether|wlan)/ ;
	}
	unlink $tempmodule;
      } else {
	print STDERR "Cannot locate module $module specified in $configfile\n";
      }
    }
    if ( $modulesets->{$module} ) {
      if ( $vendor ) {
	print "$module ($vendor,$device) listed in $configfile\n" if $verbosity >= 2;
	printf $dhcpfh ( "    if option etherboot.nic-dev-id = %02x:%02x:%02x:%02x:%02x { option etherboot.kmod \"%s\"; }\n",
			 EB_PCI_DEVICE,
			 ( hex($vendor) >> 8 ) & 0xff, hex($vendor) & 0xff,
			 ( hex($device) >> 8 ) & 0xff, hex($device) & 0xff,
			 $module );
      } else {
	print "$module (without PCI IDs) listed in $configfile\n" if $verbosity >= 2;
      }
    }
  }
  close CF;
  print $dhcpfh "\n";
  chdir $cwd;
}

my $conffile = '/etc/mknbi-set.conf';
my $mkinitrd_net = 'mkinitrd-net';
my $mknbi = 'mknbi-linux';
my $output_dir = '/var/lib/tftpboot';
my $dhcpfile = '/etc/dhcpd.conf.etherboot-pcimap.include';
my $use_local;
our $verbosity = 1;
my $modulesets = {};
my $kernel = '';
my @kernels = ();

my $usage="Usage: $0 [-l|--local] [-q] [-v] [-r|--refresh module[,module...]] [--help]";

# Parse command-line options
while ( $_ = shift ) {
  if ( /-l|--local/ ) {
    $conffile = 'mknbi-set.conf';
    $mkinitrd_net = './mkinitrd-net';
    $mknbi = './mknbi-linux --format=nbi --target=linux';
    $output_dir = 'tftpboot';
    $dhcpfile = 'tftpboot/dhcpd.conf.etherboot-pcimap.include';
    $use_local = 1;
  } elsif ( /-r|--refresh/ ) {
    my $moduleset = shift;
    $modulesets->{$moduleset} = 1;
  } elsif ( /-k|--kernel/ ) {
    $kernel = shift;
  } elsif ( /-v|--verbose/ ) {
    $verbosity++;
  } elsif ( /-q|--quiet/ ) {
    $verbosity--;
  } elsif ( /--help/ ) {
    die "$usage\n".
	"  -k, --kernel   Build NBIs for a particular kernel\n".
        "  -l, --local    Run locally from CVS (for developers only)\n".
	"  -r, --refresh  Refresh NBI for a particular module\n".
	"  -v, --verbose  Be more verbose\n".
	"  -q, --quiet    Be less verbose\n";
  } else {
    die "$usage\n";
  }
}

# Get set of current kernels
if ($kernel) {
  @kernels = ( $kernel );
} else {
  @kernels = glob('/boot/vmlinuz*');
}
die "Could not find any kernels in /boot\n" unless @kernels;

# If modules have been specified via --refresh, do not scan for modules or rewrite the
# dhcpd.conf fragment file
unless ( %$modulesets ) {
  # Write dhcpd.conf fragment file
  open my $dhcpfh, ">$dhcpfile" or die "Could not open $dhcpfile for writing: $!\n";
  print $dhcpfh "# Etherboot PCI ID -> Linux kernel module mapping file\n";
  print $dhcpfh "# Generated by mknbi-set on ".(scalar localtime)."\n";
  print $dhcpfh "#\n";
  print $dhcpfh "if substring ( option vendor-class-identifier, 0, 9 ) = \"Etherboot\" {\n";
  print $dhcpfh "  if exists etherboot.nic-dev-id {\n";
  print $dhcpfh "    \# Legacy nic-dev-id mechanism: there are some DLink DFE538 cards in circulation that\n";
  print $dhcpfh "    \# predated the change to the new nic-dev-id binary structure\n";
  print $dhcpfh "    if option etherboot.nic-dev-id = \"PCI:1186:1300\" { option etherboot.kmod \"8139too\"; }\n";
  print $dhcpfh "\n";

  # Get set of network modules to build NBIs for
  # Read explicitly-specified module sets from $conffile
  read_config_file($conffile, $modulesets, $dhcpfh, 1);
  # Obtain list of all network modules from pcimap file
  my $pcimap;
  foreach ( `/sbin/modprobe -c` ) {
    $pcimap = $1 if /^pcimap.*?=(.*)$/;
  }
  if ( $pcimap ) {
    read_config_file($pcimap, $modulesets, $dhcpfh, 0);
  } else {
    print STDERR "Could not identify pcimap file\n";
  }
  # Finish off dhcpd.conf fragment file
  print $dhcpfh "  }\n}\n";
  close $dhcpfh;
}

# Build initrd and nbi for each kernel-moduleset combination
foreach my $moduleset ( sort keys %$modulesets ) {
  next unless $modulesets->{$moduleset}; # Ignore if value is 0
  print "Building NBIs for module set $moduleset\n" if $verbosity >= 1;
  foreach my $kernel ( @kernels ) {
    ( my $kernel_ver, my $output_id ) = calc_output_id ( $kernel, $moduleset );
    if ( -l $kernel ) {
      # Symbolic link; create matching symlink
      my $real_kernel = readlink ( $kernel );
      ( my $real_kernel_ver, my $real_output_id ) = calc_output_id ( $real_kernel, $moduleset );
      print "Symlinking $output_id to $real_output_id\n" if $verbosity >= 2;
      my $initrd_file = "$output_dir/initrd-$output_id.img";
      unlink ( $initrd_file ) if -l $initrd_file;
      system ( "ln -s initrd-$real_output_id.img $initrd_file" ) == 0 or print STDERR "Could not symlink $initrd_file to initrd-$real_output_id.img: $!\n";
      my $nbi_file = "$output_dir/boot-$output_id.nbi";
      unlink ( $nbi_file ) if -l $nbi_file;
      system ( "ln -s boot-$real_output_id.nbi $nbi_file" ) == 0 or print STDERR "Could not symlink $nbi_file to boot-$real_output_id.nbi: $!\n";
    } else {
      # Real file: create initrd and nbi
      print "Creating initrd and nbi for $output_id\n" if $verbosity >= 2;
      ( my $moduleset_spaces = $moduleset ) =~ tr/,/ /;
      my $initrd_cmd = "$mkinitrd_net --nolink ".
	  ( $use_local ? "--local " : "" ).
	      ( $kernel_ver ? "--kernel $kernel_ver " : "" ).
		  ( $verbosity >= 2 ? "" : "-q " ).
		      $moduleset_spaces;
      print "$initrd_cmd\n" if $verbosity >= 3;
      if ( system ( $initrd_cmd ) == 0 ) {
	my $mknbi_cmd = "$mknbi $kernel $output_dir/initrd-$output_id.img > $output_dir/boot-$output_id.nbi";
	print "$mknbi_cmd\n" if $verbosity >= 3;
	system ( $mknbi_cmd ) == 0 or print STDERR "mknbi failed: $!\n";
      } else {
	print STDERR "$initrd_cmd failed: $!\n";
      }
    }
  }
}