REQUIRE_IMAGE_METADATA=1 get_magic_at() { local pos="$2" get_image "$1" | dd bs=1 count=2 skip="$pos" 2>/dev/null | hexdump -v -n 2 -e '1/1 "%02x"' } platform_check_image() { local diskdev partdev diff [ "$#" -gt 1 ] && return 1 case "$(get_magic_at "$1" 510)" in 55aa) ;; *) echo "Failed to verify MBR boot signature." return 1 ;; esac export_bootdevice && export_partdevice diskdev 0 || { echo "Unable to determine upgrade device" return 1 } get_partitions "/dev/$diskdev" bootdisk #extract the boot sector from the image get_image "$@" | dd of=/tmp/image.bs count=1 bs=512b 2>/dev/null get_partitions /tmp/image.bs image #compare tables diff="$(grep -F -x -v -f /tmp/partmap.bootdisk /tmp/partmap.image)" rm -f /tmp/image.bs /tmp/partmap.bootdisk /tmp/partmap.image if [ -n "$diff" ]; then echo "Partition layout has changed. Full image will be written." ask_bool 0 "Abort" && exit 1 return 0 fi } platform_copy_config() { local partdev if export_partdevice partdev 1; then mount -o rw,noatime "/dev/$partdev" /mnt cp -af "$UPGRADE_BACKUP" "/mnt/$BACKUP_FILE" umount /mnt fi } platform_do_upgrade() { local diskdev partdev diff export_bootdevice && export_partdevice diskdev 0 || { echo "Unable to determine upgrade device" return 1 } sync if [ "$UPGRADE_OPT_SAVE_PARTITIONS" = "1" ]; then get_partitions "/dev/$diskdev" bootdisk #extract the boot sector from the image get_image "$@" | dd of=/tmp/image.bs count=1 bs=512b get_partitions /tmp/image.bs image #compare tables diff="$(grep -F -x -v -f /tmp/partmap.bootdisk /tmp/partmap.image)" else diff=1 fi if [ -n "$diff" ]; then get_image "$@" | dd of="/dev/$diskdev" bs=4096 conv=fsync # Separate removal and addtion is necessary; otherwise, partition 1 # will be missing if it overlaps with the old partition 2 partx -d - "/dev/$diskdev" partx -a - "/dev/$diskdev" return 0 fi #write uboot image get_image "$@" | dd of="$diskdev" bs=512 skip=1 seek=1 count=4097 conv=fsync,notrunc #iterate over each partition from the image and write it to the boot disk while read part start size; do if export_partdevice partdev $part; then echo "Writing image to /dev/$partdev..." get_image "$@" | dd of="/dev/$partdev" ibs="512" obs=1M skip="$start" count="$size" conv=fsync else echo "Unable to find partition $part device, skipped." fi done < /tmp/partmap.image #copy partition uuid echo "Writing new UUID to /dev/$diskdev..." get_image "$@" | dd of="/dev/$diskdev" bs=1 skip=440 count=4 seek=440 conv=fsync }