Add support for Grub 2.06 (latest version) on virtual disk

[tgiphil]

• Copy bootimage.img to MBR block
• Patch MBR as necessary
• Copy diskboot.img to first sector block (in gap partition)
• Patch first sector as necessary
• Copy core.img to gap partition

References:

• https://www.gnu.org/software/grub/manual/grub/html_node/Images.html
• https://wiki.osdev.org/GRUB

Notes:

• Build virtual disk using Linux tools and then extract the core.img that was placed in the gap partition created by grub-mkimage
• Reverse engineer how grub passes blocks between the boot stages

grub-mkimage -v -O i386-pc -d. -p\(hd0,msdos1\)/boot/grub biosdisk part_msdos fat ntfs exfat -o core.img
dd if=boot.img of=/dev/sdb bs=446 count=1
dd if=core.img of=/dev/sdb bs=512 seek=1 # seek=1 skips the first block (MBR)

[tgiphil]

Closing due to transition to Limine bootloader