diff options
| -rwxr-xr-x | isohybrid-acritox | 40 |
1 files changed, 25 insertions, 15 deletions
diff --git a/isohybrid-acritox b/isohybrid-acritox index 657f377..68d8206 100755 --- a/isohybrid-acritox +++ b/isohybrid-acritox @@ -346,29 +346,39 @@ print "iso_pos: $iso_pos iso_size: $iso_size\n" if($debug); print "final imgsize: $imgsize\n" if($debug); # Calculate and write partiton table (MBR) -$h = 64; $s = 32; -$hpc = 32; $spt = 63; -$cc = min(1024, $imgsize/$cylsize); +sub lba2chs +{ + my $lba = @_; + my $hpc = 64, $spt = 32, $c, $h, $s; + $c = $lba / ($spt * $hpc); + $h = ($lba / $spt) % $hpc; + $s = ($lba % $spt) + 1; + if($c >= 1024) + { + $c = 1023; + $h = 254; + $s = 63; + } + # Head Sect Cyl + # <-Byte-> <-Byte-> <-Byte-> + # 76543210 98543210 76543210 + # HHHHHHHH CCSSSSSS CCCCCCCC + $s += ($c & 0x300) >> 2; + $c &= 0xff; + return ($c, $h, $s); +} $pentry = 1; $fstype = 0xEF; -$bcyl = $fat_pos_lba / ($spt * $hpc); -$bhead = ($fat_pos_lba / $spt) % $hpc; -$bsect = ($fat_pos_lba % $spt) + 1; -$ehead = $h-1; -$esect = $s + ((($cc-1) & 0x300) >> 2); -$ecyl = ($cc-1) & 0xff; +($bcyl, $bhead, $bsect) = lba2chs($fat_pos_lba); +($ecyl, $ehead, $esect) = lba2chs($fat_pos_lba+$fat_size_lba-1); seek(FIMG, 430+16*$pentry, SEEK_SET) or die "$0: $file: $!\n"; print FIMG pack("CCCCCCCCVV", 0x80, $bhead, $bsect, $bcyl, $fstype, $ehead, $esect, $ecyl, $fat_pos_lba, $fat_size_lba); $pentry = 2; $fstype = 0x83; -$bcyl = $iso_pos_lba / ($spt * $hpc); -$bhead = ($iso_pos_lba / $spt) % $hpc; -$bsect = ($iso_pos_lba % $spt) + 1; -$ehead = $h-1; -$esect = $s + ((($cc-1) & 0x300) >> 2); -$ecyl = ($cc-1) & 0xff; +($bcyl, $bhead, $bsect) = lba2chs($iso_pos_lba); +($ecyl, $ehead, $esect) = lba2chs($iso_pos_lba+$iso_size_lba-1); seek(FIMG, 430+16*$pentry, SEEK_SET) or die "$0: $file: $!\n"; print FIMG pack("CCCCCCCCVV", 0x00, $bhead, $bsect, $bcyl, $fstype, $ehead, $esect, $ecyl, $iso_pos_lba, $iso_size_lba); |