source: vbox/trunk/src/VBox/Devices/PC/Etherboot-src/util/makelilo.pl@ 26302

#!/usr/bin/perl -w

use constant SYSSIZE_LOC => 500;        # bytes from beginning of boot block
use constant MINSIZE => 32768;

use strict;

use bytes;

$#ARGV >= 1 or die "Usage: $0 liloprefix file ...\n";
open(L, "$ARGV[0]") or die "$ARGV[0]: $!\n";
undef($/);
my $liloprefix = <L>;
close(L);
length($liloprefix) >= 512 or die "LILO prefix too short\n";
shift(@ARGV);
my $totalsize = 0;
for my $file (@ARGV) {
        next if (! -f $file or ! -r $file);
        $totalsize += -s $file;
}
my $pad = 0;
if ($totalsize < MINSIZE) {
        $pad = MINSIZE - $totalsize;
        $totalsize = MINSIZE;
}
print STDERR "LILO payload is $totalsize bytes\n";
$totalsize += 16;
$totalsize >>= 4;
substr($liloprefix, SYSSIZE_LOC, 2) = pack('v', $totalsize);
print $liloprefix;
for my $file (@ARGV) {
        next unless open(I, "$file");
        undef($/);
        my $data = <I>;
        print $data;
        close(I);
}
print "\x0" x $pad;
exit(0);