Initial version

README.md

@@ -1,2 +1,20 @@
-# rpi2GPT
-Copy a raspiOS image to a GPT-partitioned device
+# rpi-img2GPT
+Copy a raspiOS disk image to a GPT-partitioned device (eg. hard disk)
+
+## Usage:
+```
+sudo rpi-img2GPT -d|--device device_name -i|--image rpi_disk_image
+```
+
+Example:
+
+sudo rpi-img2GPT --device /dev/sdc --image 2021-05-07-raspios-buster-armhf-lite.img
+
+## What the command does
+This command will:
+- Erase the specified device (usually a hard disk)
+- Partition the device with the GPT scheme and create 2 partitions - boot (64MB) and root (the rest of the device)
+- Copy the content of the disk image to the device
+- Change the file boot/config.txt to define a 2 x 5-second-delay to run the bootloader and kernel to leave enough time for the device to spin
+- Change the file boot/cmdline.txt to define the new root mount (switching in the process to PARTLABEL from PARTUUID) and remove the call to the initial root partition resize
+- Change the file root/etc/fstab to define the 2 mount points - /boot and / - (switching in the process to PARTLABEL from PARTUUID)

rpi-img2GPT

@@ -0,0 +1,191 @@
+#!/bin/bash
+
+DisplayUsage() {
+
+	cat <<-EOF
+
+	${COMMAND} copies a raspiOS disk image to a GPT-partitioned device and performs a few adjustments to allow the raspberry-pi to boot directly from the device.
+
+	Usage: 
+	${COMMAND} --device|-d device_name --image|-i disk_image
+
+	EOF
+
+	exit 0
+}
+
+GetArguments() {
+	## Translate long options to short ones
+	for arg in $@; do
+		delim=""
+		case ${arg} in
+			"--help") 	args="${args}-h" ;;
+			"--device") args="${args}-d" ;;
+			"--image")	args="${args}-i" ;;
+			*)			[[ "${arg:0:1}" == "-" ]] || delim="\""
+      					args="${args}${delim}${arg}${delim} ";;
+		esac
+	done
+
+	# reset the translated args
+	eval set -- "${args}"
+
+	## Parse short options
+	while getopts "hd:i:" opt; do
+		case ${opt} in
+			"h")	DisplayUsage; exit 0 ;;
+			"d")	DEVICE_NAME=${OPTARG} ;;
+			"i")	DISK_IMAGE=${OPTARG} ;;
+			*)		DisplayUsage ;;
+		esac
+	done
+}
+
+CheckConditions() {
+
+	# Check that the program is run by root
+	if [ $(id -u) -ne 0 ]; then
+		echo "${COMMAND} must be run as root" >&2
+		exit 1
+	fi
+
+	# Check that the device exists
+	if [ -z ${DEVICE_NAME} ]; then
+		echo "Device name not specified" >&2
+		exit 2
+	fi
+
+	mountpoints=$(lsblk --noheadings --list -o MOUNTPOINTS ${DEVICE_NAME} 2>/dev/null)
+	if [ ${?} -ne 0 ]; then
+		echo "Device ${DEVICE_NAME} not found" >&2
+		exit 3
+	fi
+
+	# Check that the disk image exists
+	if [ -z ${DISK_IMAGE} ]; then
+		echo "Disk image not specified" >&2
+		exit 4
+	fi
+
+	if [ ! -f ${DISK_IMAGE} ]; then
+		echo "Disk image ${DISK_IMAGE} not found" >&2
+		exit 5
+	fi
+}
+
+Cleanup() {
+
+	echo "Cleaning up..."
+	# Unmount partitions
+	umount ${TEMP_DIR}/*
+
+	# Unmap disk image
+	kpartx -d ${DISK_IMAGE}
+
+	# Delete the temporary directory
+	if [ -d ${TEMP_DIR} ]; then
+		rm -rf ${TEMP_DIR}
+	fi
+}
+
+# Initialize the program
+
+## Set constants
+readonly COMMAND=$(basename ${0})
+
+## Get arguments
+GetArguments $@
+
+## Check conditions
+CheckConditions
+
+## Set program execution flags
+set -euo pipefail
+
+## Intercept interruptions
+trap Cleanup SIGHUP SIGINT SIGQUIT SIGABRT SIGTERM
+
+# STEP-1: Prepare the hard disk
+## unmount the partitions of the specified device, if any
+for mp in ${mountpoints}; do 
+	umount ${mp}
+done
+
+## Remove previous content
+echo "Erasing device ${DEVICE_NAME}..."
+sgdisk --zap-all ${DEVICE_NAME} 1>/dev/null
+
+## Create 2 partitions
+echo "Preparing device ${DEVICE_NAME}..."
+sgdisk --new=0:0:+64M --typecode=0:0700 --change-name=0:boot ${DEVICE_NAME} 1>/dev/null
+sgdisk --new=0:0:0 --typecode=0:8300 --change-name=0:root ${DEVICE_NAME} 1>/dev/null
+
+## Create an hybrid MBR with partition type "0c" so that bootloader finds it
+cat << EOF | gdisk ${DEVICE_NAME} 1>/dev/null
+r
+h
+1
+N
+0c
+N
+Y
+EE
+w
+Y
+EOF
+
+## Format the 3 partitions 
+mkfs.fat -F 32 -n BOOT ${DEVICE_NAME}1 1>/dev/null 2>&1
+mkfs.ext4 -F -L root ${DEVICE_NAME}2 1>/dev/null
+
+# STEP-2: Copy the content of the disk image to the hard disk
+## Create a temporary directory
+readonly TEMP_DIR=$(mktemp -d)
+
+## Mount the 2 hard-disk partitions
+mkdir ${TEMP_DIR}/d1
+mount ${DEVICE_NAME}1 ${TEMP_DIR}/d1
+mkdir ${TEMP_DIR}/d2
+mount ${DEVICE_NAME}2 ${TEMP_DIR}/d2
+
+## Map the disk image to a loop device
+readonly LIST_MAPPINGS=$(kpartx -asv ${DISK_IMAGE})
+
+## Mount the 2 disk image partitions
+device=$(echo ${LIST_MAPPINGS} | cut -d" " -f3)
+mkdir ${TEMP_DIR}/s1
+mount /dev/mapper/${device} ${TEMP_DIR}/s1
+
+device=$(echo ${LIST_MAPPINGS} | cut -d" " -f12)
+mkdir ${TEMP_DIR}/s2
+mount /dev/mapper/${device} ${TEMP_DIR}/s2
+
+## Copy content of the disk image to the device
+echo "Copying boot-partition files..."
+rsync -a ${TEMP_DIR}/s1/ ${TEMP_DIR}/d1 
+echo "Copying root-partition files..."
+rsync -a ${TEMP_DIR}/s2/ ${TEMP_DIR}/d2 
+
+# STEP-3: adjust some settings
+
+## /boot/config.txt: Add bootcode_delay and boot_delay
+echo "Making few adjustments..."
+echo 'bootcode_delay=5' >> ${TEMP_DIR}/d1/config.txt
+echo 'boot_delay=5' >> ${TEMP_DIR}/d1/config.txt
+
+## /boot/cmdline.txt: Remove one-time root file system resizing, quiet option and fsck option
+sed -e 's; init=/usr/lib/raspi-config/init_resize.sh;;' -i ${TEMP_DIR}/d1/cmdline.txt
+sed -e 's; quiet;;' -i ${TEMP_DIR}/d1/cmdline.txt
+sed -e 's; fsck.repair=yes; fsck.repair=no;' -i ${TEMP_DIR}/d1/cmdline.txt
+
+## Change mount point in /boot/cmdline.txt 
+sed -e 's;root=PARTUUID=[0-9,a-f,\-]*;root=PARTLABEL=root;' -i ${TEMP_DIR}/d1/cmdline.txt
+
+## Change mount points in /etc/fstab 
+sed -e 's;^PARTUUID=.*/boot;PARTLABEL=boot \t/boot;' -i ${TEMP_DIR}/d2/etc/fstab
+sed -e 's;^PARTUUID=.*/[[:blank:]];PARTLABEL=root \t/;' -i ${TEMP_DIR}/d2/etc/fstab
+
+# Clean up and exit
+Cleanup
+echo "Operation completed"
+exit 0