shredos.x86_64/fs/iso9660/Config.in

config BR2_TARGET_ROOTFS_ISO9660
	bool "iso image"
	depends on (BR2_i386 || BR2_x86_64)
	depends on BR2_LINUX_KERNEL
	depends on BR2_TARGET_GRUB2 || BR2_TARGET_SYSLINUX_ISOLINUX
	select BR2_LINUX_KERNEL_INSTALL_TARGET \
		if (!BR2_TARGET_ROOTFS_ISO9660_INITRD && !BR2_TARGET_ROOTFS_INITRAMFS)
	help
	  Build a bootable ISO9660 image. By default, the root
	  filesystem is directly packed as the ISO9660 filesystem,
	  which means the root filesystem will be read-only. It
	  requires ISO9660 filesystem support and CDROM support in the
	  kernel.

	  However, if BR2_TARGET_ROOTFS_INITRAMFS or
	  BR2_TARGET_ROOTFS_ISO9660_INITRD have been enabled, the
	  ISO9660 filesystem will only contain a kernel image and
	  optionally an external initrd image. In this case, the
	  filesystem being in RAM, it will be read/write. No ISO9660
	  or CDROM support is needed in the kernel.

if BR2_TARGET_ROOTFS_ISO9660

choice
	prompt "Bootloader"
	depends on BR2_TARGET_ROOTFS_ISO9660

config BR2_TARGET_ROOTFS_ISO9660_GRUB2
	bool "grub2"
	depends on BR2_TARGET_ROOTFS_ISO9660
	depends on BR2_TARGET_GRUB2 \
		&& (BR2_TARGET_GRUB2_I386_EFI || BR2_TARGET_GRUB2_X86_64_EFI)
	select BR2_TARGET_ROOTFS_ISO9660_BIOS_BOOTLOADER \
		if BR2_TARGET_GRUB2_I386_PC
	select BR2_TARGET_ROOTFS_ISO9660_EFI_BOOTLOADER \
		if (BR2_TARGET_GRUB2_I386_EFI || BR2_TARGET_GRUB2_X86_64_EFI)
	help
	  Use Grub 2 as the bootloader for the ISO9660 image.
	  Make sure to enable the 'iso9660' module in
	  (when used) BR2_TARGET_GRUB2_BUILTIN_MODULES_PC and (when used)
	  BR2_TARGET_GRUB2_BUILTIN_MODULES_EFI. For GRUB on BIOS, use 'cd'
	  as the boot partition in BR2_TARGET_GRUB2_BOOT_PARTITION setting.
	  For GRUB on EFI 'set root=(cd0)' in the configuration file passed
	  to BR2_TARGET_GRUB2_BUILTIN_CONFIG_EFI, although just an ISO9660
	  BR2_TARGET_ROOTFS_ISO9660_GRUB2_EFI_BOOT_MENU containing a "search"
	  using the BR2_TARGET_ROOTFS_ISO9660_GRUB2_EFI_IDENT_FILE also works.

config BR2_TARGET_ROOTFS_ISO9660_ISOLINUX
	bool "isolinux"
	depends on BR2_TARGET_ROOTFS_ISO9660
	depends on BR2_TARGET_SYSLINUX_ISOLINUX
	select BR2_TARGET_ROOTFS_ISO9660_BIOS_BOOTLOADER
	help
	  Use ISOLINUX as the bootloader for the ISO9660 image.
	  ISOLINUX is a bootloader for BIOS systems that can boot
	  from CD-ROM or USB devices.

config BR2_TARGET_ROOTFS_ISO9660_BOTH
	bool "both"
	depends on BR2_TARGET_ROOTFS_ISO9660
	depends on BR2_TARGET_SYSLINUX_ISOLINUX
	depends on BR2_TARGET_GRUB2 \
		&& (BR2_TARGET_GRUB2_I386_EFI || BR2_TARGET_GRUB2_X86_64_EFI)
	select BR2_TARGET_ROOTFS_ISO9660_BIOS_BOOTLOADER
	select BR2_TARGET_ROOTFS_ISO9660_EFI_BOOTLOADER
	help
	  Use both ISOLINUX (for BIOS boot) and GRUB2 (for UEFI boot).
	  This creates an ISO that can boot on both legacy BIOS
	  systems and modern UEFI systems, combined with the hybrid
	  image option this will produce a Debian-style hybrid ISO,
	  as it is commonly shipped alongside modern Linux distros,
	  which can both be flashed to USB and burned to CD/DVD-ROM.

endchoice

config BR2_TARGET_ROOTFS_ISO9660_BIOS_BOOTLOADER
	bool

config BR2_TARGET_ROOTFS_ISO9660_EFI_BOOTLOADER
	bool

config BR2_TARGET_ROOTFS_ISO9660_VOLUME_NAME
	string "iso volume name"
	depends on BR2_TARGET_ROOTFS_ISO9660
	default "ISO9660"
	help
	  Set the Volume ID of the ISO image. xorriso accepts any text up to 32
	  characters, but according to rarely obeyed specs stricter rules apply:
	  Conformant are ASCII characters out of [A-Z0-9_], like: "IMAGE_23". Joliet
	  allows 16 UCS-2 characters, like: "Windows name". Be aware that the volume
	  ID might get used automatically as name of the mount point when the medium
	  is inserted into a playful computer system.

config BR2_TARGET_ROOTFS_ISO9660_ISOLINUX_BOOT_MENU
	string "Isolinux configuration file"
	depends on BR2_TARGET_ROOTFS_ISO9660
	depends on BR2_TARGET_ROOTFS_ISO9660_ISOLINUX || BR2_TARGET_ROOTFS_ISO9660_BOTH
	default "fs/iso9660/isolinux.cfg"
	help
	  Use this option to provide a custom ISOLINUX configuration
	  file (isolinux.cfg).

	  Note that the strings __KERNEL_PATH__ and __INITRD_PATH__
	  will automatically be replaced by the path to the kernel and
	  initrd images respectively (or removed, if not applicable).

config BR2_TARGET_ROOTFS_ISO9660_GRUB2_BOOT_MENU
	string "Grub2 configuration file"
	depends on BR2_TARGET_ROOTFS_ISO9660
	depends on BR2_TARGET_ROOTFS_ISO9660_GRUB2 || BR2_TARGET_ROOTFS_ISO9660_BOTH
	default "fs/iso9660/grub.cfg"
	help
	  Use this option to provide a custom GRUB2 configuration
	  file (grub.cfg).

	  Note that the strings __KERNEL_PATH__ and __INITRD_PATH__
	  will automatically be replaced by the path to the kernel and
	  initrd images respectively (or removed, if not applicable).

config BR2_TARGET_ROOTFS_ISO9660_GRUB2_EFI_BOOT_MENU
	string "Grub2 configuration file (EFI)"
	depends on BR2_TARGET_ROOTFS_ISO9660
	depends on (BR2_TARGET_ROOTFS_ISO9660_GRUB2 || BR2_TARGET_ROOTFS_ISO9660_BOTH) \
		&& BR2_TARGET_ROOTFS_ISO9660_EFI_BOOTLOADER
	default "fs/iso9660/efigrub.cfg"
	help
	  Use this option to provide a custom GRUB2 configuration
	  file (grub.cfg), copied both to the EFI partition and the
	  ISO9660 filesystem EFI-structure (for an EFI bootloader to find).

	  It will usually contain a "search" and "source" directive to find
	  the ISO9660 filesystem containing a common (BIOS) GRUB2 configuration.
	  Alternatively, 'set root=(cd0)' and other such quirks are possible here.

	  This is specifically for directives required for ISO9660 builds, for
	  baking an EFI search config into the common GRUB image (often better)
	  check out instead the GRUB2 setting: BR2_TARGET_GRUB2_BUILTIN_CONFIG_EFI

	  Note that the strings __KERNEL_PATH__ and __INITRD_PATH__
	  will automatically be replaced by the path to the kernel and
	  initrd images respectively (or removed, if not applicable).

	  Note that any string __EFI_ID_FILE__ will automatically be
	  replaced with the BR2_TARGET_ROOTFS_ISO9660_GRUB2_EFI_IDENT_FILE.

config BR2_TARGET_ROOTFS_ISO9660_GRUB2_EFI_IDENT_FILE
	string "Grub2 identification file (EFI)"
	depends on BR2_TARGET_ROOTFS_ISO9660
	depends on (BR2_TARGET_ROOTFS_ISO9660_GRUB2 || BR2_TARGET_ROOTFS_ISO9660_BOTH) \
		&& BR2_TARGET_ROOTFS_ISO9660_EFI_BOOTLOADER
	default "/boot/buildroot"
	help
	  Use this option to provide a custom name for the identification
	  file that is added to the ISO9660 filesystem, so the EFI bootloader
	  can better "search" it among possibly multiple attached boot devices.

config BR2_TARGET_ROOTFS_ISO9660_GRUB2_EFI_PARTITION_SIZE
	string "Grub2 partition size (EFI)"
	depends on BR2_TARGET_ROOTFS_ISO9660
	depends on (BR2_TARGET_ROOTFS_ISO9660_GRUB2 || BR2_TARGET_ROOTFS_ISO9660_BOTH) \
		&& BR2_TARGET_ROOTFS_ISO9660_EFI_BOOTLOADER
	default "3M"
	help
	  Use this option to increase the size of the EFI partition.
	  Embedding more GRUB2 modules may require a larger EFI partition size.

	  Beware that sizes above 32M may not be compatible with all systems.
	  xorriso will raise warnings, but not fail partitions larger than 32M.
	  If you exceed 32M, carefully examine your builds and partition layouts.

config BR2_TARGET_ROOTFS_ISO9660_INITRD
	bool "Use initrd"
	depends on BR2_TARGET_ROOTFS_ISO9660
	depends on !BR2_TARGET_ROOTFS_INITRAMFS
	default y
	select BR2_TARGET_ROOTFS_CPIO
	help
	  Enable this option to have the root filesystem bundled as an
	  initrd/initramfs rather than directly as the ISO9660
	  filesystem. With this option enabled, the ISO9660 will only
	  contain a kernel image, an initrd image (unless an initramfs
	  linked into the kernel is used) and the bootloader.

config BR2_TARGET_ROOTFS_ISO9660_TRANSPARENT_COMPRESSION
	bool "transparent compression"
	depends on BR2_TARGET_ROOTFS_ISO9660
	depends on !BR2_TARGET_ROOTFS_ISO9660_INITRD
	depends on !BR2_TARGET_ROOTFS_INITRAMFS
	help
	  Enables the use of transparent (de)compression. All files
	  are stored compressed and will be decompressed on-the-fly
	  upon access at runtime.

config BR2_TARGET_ROOTFS_ISO9660_HYBRID
	bool "Build hybrid image"
	depends on BR2_TARGET_ROOTFS_ISO9660
	depends on BR2_TARGET_ROOTFS_ISO9660_ISOLINUX || BR2_TARGET_ROOTFS_ISO9660_BOTH
	help
	  Enable this option to build a hybrid image, which is an image
	  that can either be burned to CD/DVD-ROM or flashed onto a device
	  which the BIOS considers as HDD/removable device (e.g. USB stick)

config BR2_TARGET_ROOTFS_ISO9660_HYBRID_APPEND_PARTITION
	string "Append partition to hybrid image"
	depends on BR2_TARGET_ROOTFS_ISO9660
	depends on BR2_TARGET_ROOTFS_ISO9660_BOTH
	depends on BR2_TARGET_ROOTFS_ISO9660_HYBRID
	default ""
	help
	  Enable this option to append a prepared filesystem image
	  to the hybrid image, useful when needing a writeable data
	  partition for USBs - should be considered as EXPERIMENTAL.

	  The path is expected to be relative to folder "output/images/".

	  You can use e.g. a BR2_ROOTFS_POST_BUILD_SCRIPT for preparing
	  the respective filesystem image for your target configuration.

config BR2_TARGET_ROOTFS_ISO9660_HYBRID_APPEND_PARTITION_TYPE
	string "Append partition type"
	depends on BR2_TARGET_ROOTFS_ISO9660
	depends on BR2_TARGET_ROOTFS_ISO9660_BOTH
	depends on BR2_TARGET_ROOTFS_ISO9660_HYBRID
	depends on BR2_TARGET_ROOTFS_ISO9660_HYBRID_APPEND_PARTITION != ""
	default "0x0e"
	help
	  May be "FAT12", "FAT16", "Linux", or a hexadecimal number between 0x00 and
	  0xff. Not all those numbers will yield usable results. For a list of codes
	  search the internet for "Partition Types". If the partition appears in GPT
	  then 0xef is mapped to the EFI System Partition Type GUID. All others get
	  mapped to Basic Data Type GUID. May also be a type GUID as plain hex
	  string like a2a0d0ebe5b9334487c068b6b72699c7 or as structured text like
	  EBD0A0A2-B9E5-4433-87C0-68B6B72699C7. It will be used if the partition is
	  mentioned in GPT. In MBR, C12A7328-F81F-11D2-BA4B-00A0C93EC93B will be
	  mapped to 0xef. Any other GUID will be mapped to 0x83.

endif

comment "iso image needs a Linux kernel and either grub2 or isolinux to be built"
	depends on BR2_i386 || BR2_x86_64
	depends on !BR2_LINUX_KERNEL || \
		!(BR2_TARGET_GRUB2 || BR2_TARGET_SYSLINUX_ISOLINUX)