From d471be96c075ce20ed75fbbe4c7164de74b5eaa5 Mon Sep 17 00:00:00 2001
From: Matthijs Kooijman <matthijs@stdin.nl>
Date: Thu, 4 Apr 2024 15:46:24 +0200
Subject: [PATCH 1/4] Let sfdisk generate new disk id when initializing

This removes the old disk id from the info passed to sfdisk, forcing it
to generate a new disk id instead of preserving the old disk id when
updating the partition table. This allows removing the code that
randomizes the disk id after sfdisk updated the partition table. Also
note that this code was previously already redudundant because after
initializing there is more code that changes the disk id if it is
identical (to support the non-initializing flow, but that is also run
when initializing).
---
 rpi-clone | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/rpi-clone b/rpi-clone
index 22e53a4..2752389 100755
--- a/rpi-clone
+++ b/rpi-clone
@@ -1426,6 +1426,9 @@ Use -U for unattended even if initializing.
 	part="${src_part_base}$n_image_parts"
 	sfd1=$(echo "$sfd0" | sed "\/dev\/$part/s/size=[^,]*,//")
 
+	# Strip label-id, to let sfdisk generate a new disk id
+	sfd1=$(echo "$sfd1" | grep -v '^label-id: ')
+
 	if ((ext_part_num > 0 && !force_2_parts))
 	then
 		part="${src_part_base}$ext_part_num"
@@ -1466,17 +1469,11 @@ Use -U for unattended even if initializing.
 		fi
 	done
 	printf "\n    Resize success.\n"
-	printf "  Changing destination Disk ID ..."
-	sync
-	sleep 2
 
-	new_id=$(od -A n -t x -N 4 /dev/urandom | tr -d " ")
-	qprintf "x\ni\n0x$new_id\nr\nw\nq\n" | fdisk /dev/$dst_disk > /dev/null
 	sync
 	sleep 2
 	partprobe "/dev/$dst_disk"
 	sleep 2
-	echo ""
 
 	for ((p = n_image_parts + 1; p <= n_src_parts; p++))
 	do

From e2b3f56521106cddfc9a95420b7b0719ccbfddb4 Mon Sep 17 00:00:00 2001
From: Matthijs Kooijman <matthijs@stdin.nl>
Date: Thu, 4 Apr 2024 15:52:14 +0200
Subject: [PATCH 2/4] Introduce change_disk_id() function

This removes some duplicate code, preparing for making that code more
complex to support GPT in an upcoming commit.
---
 rpi-clone | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/rpi-clone b/rpi-clone
index 2752389..368aa41 100755
--- a/rpi-clone
+++ b/rpi-clone
@@ -567,6 +567,12 @@ ext_label()
 	printf -v "${4}" "%s" "$label_arg"
 	}
 
+change_disk_id()
+	{
+	new_id=$(od -A n -t x -N 4 /dev/urandom | tr -d " ")
+	sfdisk --disk-id "$1" "$new_id"
+	}
+
 get_src_disk()
 	{
 	partition=${1#/dev/}
@@ -1463,8 +1469,7 @@ Use -U for unattended even if initializing.
 			printf "    Try running $PGM again.\n\n"
 
 			# Don't let dst disk keep source disk ID.  Can lead to remounts.
-			new_id=$(od -A n -t x -N 4 /dev/urandom | tr -d " ")
-			qprintf "x\ni\n0x$new_id\nr\nw\nq\n" | fdisk /dev/$dst_disk > /dev/null
+			change_disk_id "/dev/$dst_disk"
 			exit 1
 		fi
 	done
@@ -1634,8 +1639,7 @@ dst_disk_ID=${line#*x}
 if [ "$dst_disk_ID" == "$src_disk_ID" ]
 then
 	qecho "Destination disk has same Disk ID as source, changing it."
-	new_id=$(od -A n -t x -N 4 /dev/urandom | tr -d " ")
-	qprintf "x\ni\n0x$new_id\nr\nw\nq\n" | fdisk /dev/$dst_disk | grep changed
+	change_disk_id "/dev/$dst_disk"
 	sync
 	sleep 2
 	partprobe "/dev/$dst_disk"

From b43dd66a4d14f0670c44f5d28336f68cc38a6480 Mon Sep 17 00:00:00 2001
From: Matthijs Kooijman <matthijs@stdin.nl>
Date: Thu, 4 Apr 2024 15:53:13 +0200
Subject: [PATCH 3/4] Use sfdisk for getting the disk id

The sfdisk command has a convenient `--disk-id` option, saving the need
to use grep to parse fdisk output.
---
 rpi-clone | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/rpi-clone b/rpi-clone
index 368aa41..d773ebb 100755
--- a/rpi-clone
+++ b/rpi-clone
@@ -652,9 +652,7 @@ src_df_table=$(echo "$tmp" | sed "s/root/$dev/")
 n_src_parts=$(echo "$src_partition_table" | tail -n 1 | cut -d ":" -f 1)
 src_disk_size=$(echo "$src_partition_table" \
 				| grep "^/dev/$src_disk" | cut -d ":" -f 2 | tr -d 's')
-
-line=$(fdisk -l /dev/$src_disk | grep "Disk identifier:")
-src_disk_ID=${line#*x}
+src_disk_ID=$(sfdisk --disk-id "/dev/$src_disk")
 
 src_mount_table=$(findmnt -o source,target -n -l \
 				| grep -e "^/dev/$src_disk" -e "^$src_root_dev" | tr -s " ")
@@ -1634,8 +1632,7 @@ else
 	start_sec=$(date '+%s')
 fi
 
-line=$(fdisk -l /dev/$dst_disk | grep "Disk identifier:")
-dst_disk_ID=${line#*x}
+dst_disk_ID=$(sfdisk --disk-id "/dev/$dst_disk")
 if [ "$dst_disk_ID" == "$src_disk_ID" ]
 then
 	qecho "Destination disk has same Disk ID as source, changing it."
@@ -1645,8 +1642,7 @@ then
 	partprobe "/dev/$dst_disk"
 	sleep 2
 
-	line=$(fdisk -l /dev/$dst_disk | grep "Disk identifier:")
-	dst_disk_ID=${line#*x}
+	dst_disk_ID=$(sfdisk --disk-id "/dev/$dst_disk")
 	if [ "$dst_disk_ID" == "$src_disk_ID" ]
 	then
 		qecho "  Failed to set a new Disk ID."

From 9bb92c228212548c282317b54cf56812552e3cd3 Mon Sep 17 00:00:00 2001
From: Matthijs Kooijman <matthijs@stdin.nl>
Date: Thu, 4 Apr 2024 15:54:13 +0200
Subject: [PATCH 4/4] Support GPT partition tables

The sfdisk command already handles most of what is needed. This just
removes the last-lba entry from sfdisk partition info (which is based on
the source disk size and would otherwise limit the available destination
space, if it is omitted the entire destination disk is usable), and
makes change_disk_id support generating a longer UUID disk id when a GPT
table is in use.
---
 rpi-clone | 21 ++++++++++++++++++---
 1 file changed, 18 insertions(+), 3 deletions(-)

diff --git a/rpi-clone b/rpi-clone
index d773ebb..e769e7f 100755
--- a/rpi-clone
+++ b/rpi-clone
@@ -62,8 +62,8 @@ confirm()
 	}
 
 # sfdisk is in fdisk package
-commands="rsync parted fdisk findmnt column fsck.vfat"
-packages="rsync parted util-linux mount bsdmainutils dosfstools"
+commands="rsync parted fdisk findmnt column fsck.vfat uuidgen"
+packages="rsync parted util-linux mount bsdmainutils dosfstools uuid-runtime"
 need_packages=""
 
 idx=1
@@ -569,7 +569,18 @@ ext_label()
 
 change_disk_id()
 	{
-	new_id=$(od -A n -t x -N 4 /dev/urandom | tr -d " ")
+	case "$src_disk_table_type" in
+		msdos)
+			new_id=$(od -A n -t x -N 4 /dev/urandom | tr -d " ")
+			;;
+		gpt)
+			new_id=$(uuidgen)
+			;;
+		*)
+			qecho "  Unsupported partition table, cannot change Disk ID."
+			return 1
+			;;
+	esac
 	sfdisk --disk-id "$1" "$new_id"
 	}
 
@@ -652,6 +663,8 @@ src_df_table=$(echo "$tmp" | sed "s/root/$dev/")
 n_src_parts=$(echo "$src_partition_table" | tail -n 1 | cut -d ":" -f 1)
 src_disk_size=$(echo "$src_partition_table" \
 				| grep "^/dev/$src_disk" | cut -d ":" -f 2 | tr -d 's')
+src_disk_table_type=$(echo "$src_partition_table" \
+				| grep "^/dev/$src_disk" | cut -d ":" -f 6 )
 src_disk_ID=$(sfdisk --disk-id "/dev/$src_disk")
 
 src_mount_table=$(findmnt -o source,target -n -l \
@@ -1430,6 +1443,8 @@ Use -U for unattended even if initializing.
 	part="${src_part_base}$n_image_parts"
 	sfd1=$(echo "$sfd0" | sed "\/dev\/$part/s/size=[^,]*,//")
 
+	# Strip gpt last-lba marker, if any, that will needlessly limit to the src disk size.
+	sfd1=$(echo "$sfd1" | grep -v '^last-lba: ')
 	# Strip label-id, to let sfdisk generate a new disk id
 	sfd1=$(echo "$sfd1" | grep -v '^label-id: ')