get_magic_at() { local file="$1" local pos="$2" get_image "$file" | dd bs=1 count=2 skip="$pos" 2>/dev/null | hexdump -v -n 2 -e '1/1 "%02x"' } platform_check_image_clearfog() { local file="$1" local magic magic=$(get_magic_at "$file" 510) [ "$magic" != "55aa" ] && { echo "Failed to verify MBR boot signature." return 1 } return 0; } platform_do_upgrade_clearfog() { sync get_image "$1" | dd of=/dev/mmcblk0 bs=2M conv=fsync sleep 1 } platform_copy_config_clearfog() { mkdir -p /boot [ -f /boot/kernel.img ] || mount -t vfat -o rw,noatime /dev/mmcblk0p1 /boot cp -af "$CONF_TAR" /boot/ sync umount /boot }