Fix up resize scripts

debian/changelog

@@ -1,10 +1,10 @@
-raspi-config (20200514) buster; urgency=medium
+raspi-config (20200515) buster; urgency=medium
 
   * Update initial resize script
     - Change disk ID to avoid clashes
-  * Add boot order selector
+  * Add support for USB resize
 
- -- Serge Schneider <serge@raspberrypi.org>  Thu, 14 May 2020 06:33:23 +0100
+ -- Serge Schneider <serge@raspberrypi.com>  Fri, 15 May 2020 08:47:17 +0100
 
 raspi-config (20200504) buster; urgency=medium
 

raspi-config

@@ -122,21 +122,18 @@ you have heavily customised your installation.\
 }
 
 get_can_expand() {
-  ROOT_PART=$(mount | sed -n 's|^/dev/\(.*\) on / .*|\1|p')
+  ROOT_PART="$(findmnt / -o source -n)"
+  ROOT_DEV="/dev/$(lsblk -no pkname "$ROOT_PART")"
 
-  PART_NUM=${ROOT_PART#mmcblk0p}
-  if [ "$PART_NUM" = "$ROOT_PART" ]; then
-    echo 1
-    exit
-  fi
+  PART_NUM="$(echo "$ROOT_PART" | grep -o "[[:digit:]]*$")"
 
   if [ "$PART_NUM" -ne 2 ]; then
     echo 1
     exit
   fi
 
-  LAST_PART_NUM=$(parted /dev/mmcblk0 -ms unit s p | tail -n 1 | cut -f 1 -d:)
-  if [ $LAST_PART_NUM -ne $PART_NUM ]; then
+  LAST_PART_NUM=$(parted "ROOT_DEV" -ms unit s p | tail -n 1 | cut -f 1 -d:)
+  if [ "$LAST_PART_NUM" -ne "$PART_NUM" ]; then
     echo 1
     exit
   fi
@@ -144,13 +141,10 @@ get_can_expand() {
 }
 
 do_expand_rootfs() {
-  ROOT_PART=$(mount | sed -n 's|^/dev/\(.*\) on / .*|\1|p')
+  ROOT_PART="$(findmnt / -o source -n)"
+  ROOT_DEV="/dev/$(lsblk -no pkname "$ROOT_PART")"
 
-  PART_NUM=${ROOT_PART#mmcblk0p}
-  if [ "$PART_NUM" = "$ROOT_PART" ]; then
-    whiptail --msgbox "$ROOT_PART is not an SD card. Don't know how to expand" 20 60 2
-    return 0
-  fi
+  PART_NUM="$(echo "$ROOT_PART" | grep -o "[[:digit:]]*$")"
 
   # NOTE: the NOOBS partition layout confuses parted. For now, let's only 
   # agree to work with a sufficiently simple partition layout
@@ -159,18 +153,18 @@ do_expand_rootfs() {
     return 0
   fi
 
-  LAST_PART_NUM=$(parted /dev/mmcblk0 -ms unit s p | tail -n 1 | cut -f 1 -d:)
+  LAST_PART_NUM=$(parted "$ROOT_DEV" -ms unit s p | tail -n 1 | cut -f 1 -d:)
   if [ $LAST_PART_NUM -ne $PART_NUM ]; then
     whiptail --msgbox "$ROOT_PART is not the last partition. Don't know how to expand" 20 60 2
     return 0
   fi
 
   # Get the starting offset of the root partition
-  PART_START=$(parted /dev/mmcblk0 -ms unit s p | grep "^${PART_NUM}" | cut -f 2 -d: | sed 's/[^0-9]//g')
+  PART_START=$(parted "$ROOT_DEV" -ms unit s p | grep "^${PART_NUM}" | cut -f 2 -d: | sed 's/[^0-9]//g')
   [ "$PART_START" ] || return 1
   # Return value will likely be error for fdisk as it fails to reload the
   # partition table because the root fs is mounted
-  fdisk /dev/mmcblk0 <<EOF
+  fdisk "$ROOT_DEV" <<EOF
 p
 d
 $PART_NUM
@@ -202,7 +196,7 @@ cat <<EOF > /etc/init.d/resize2fs_once &&
 case "\$1" in
   start)
     log_daemon_msg "Starting resize2fs_once" &&
-    resize2fs /dev/$ROOT_PART &&
+    resize2fs "$ROOT_PART" &&
     update-rc.d resize2fs_once remove &&
     rm /etc/init.d/resize2fs_once &&
     log_end_msg \$?

usr/lib/raspi-config/init_resize.sh

@@ -22,7 +22,7 @@ check_commands () {
       sleep 5
       return 1
   fi
-  for COMMAND in grep cut sed parted fdisk findmnt partprobe; do
+  for COMMAND in grep cut sed parted fdisk findmnt; do
     if ! command -v $COMMAND > /dev/null; then
       FAIL_REASON="$COMMAND not found"
       return 1
@@ -78,18 +78,21 @@ fix_partuuid() {
   mount -o remount,rw "$ROOT_PART_DEV"
   mount -o remount,rw "$BOOT_PART_DEV"
   DISKID="$(tr -dc 'a-f0-9' < /dev/hwrng | dd bs=1 count=8 2>/dev/null)"
-  fdisk "$ROOT_DEV" <<EOF
+  fdisk "$ROOT_DEV" > /dev/null <<EOF
 x
 i
 0x$DISKID
 r
 w
 EOF
+  if [ "$?" -eq 0 ]; then
     sed -i "s/${OLD_DISKID}/${DISKID}/g" /etc/fstab
     sed -i "s/${OLD_DISKID}/${DISKID}/" /boot/cmdline.txt
+    sync
+  fi
+
   mount -o remount,ro "$ROOT_PART_DEV"
   mount -o remount,ro "$BOOT_PART_DEV"
-  sync
 }
 
 check_variables () {