Update 200_check_usb_layout.sh

[casantos]

Issue an error message and exit if USB_DEVICE_FILESYSTEM is invalid, instead of setting it to "ext3". It's safer to fail due to configuation errors than to ignore/fix them silently.

Fixes: issue #3029

• Type: Bug Fix

• Impact: Low

• Reference to related issue (URL): ReaR should issue an error message and exit if USB_DEVICE_FILESYSTEM is invalid #3029

• How was this pull request tested?

  Ran rear mkbackup with a configuration containing

  BACKUP=NETFS
  BACKUP_PROG_COMPRESS_OPTIONS=( )
  BACKUP_PROG_COMPRESS_SUFFIX=
  BACKUP_URL=usb:///dev/disk/by-label/REAR-000
  MODULES=()
  OUTPUT=USB
  USB_BOOTLOADER=grub
  USB_DEVICE_FILESYSTEM=xfs
  USB_DEVICE_PARTED_LABEL=gpt
  USB_UEFI_PART_SIZE=2048
  SECURE_BOOT_BOOTLOADER=/boot/efi/EFI/redhat/shimx64.efi
  

• Brief description of the changes in this pull request:

Issue an error message and exit if USB_DEVICE_FILESYSTEM is invalid.

[jsmeix]

@casantos
thank you for your contribution
to make ReaR behave more in compliance with
https://github.com/rear/rear/wiki/Coding-Style

I think it is not a bug because conf/default.conf reads

# Only ext3 and ext4 are supported by the format workflow.

[jsmeix]

From plain looking at the code changes it looks good to me

[jsmeix]

@rear/contributors
please have a look here (as time permits),
perhaps I may have overlooked something.

I would like to merge it on Thursday afternoon
unless there are objections.

[pcahyna]

thank you for the change, I think that silently changing user's settings to something else because we don't like them is a bad idea (except for special defaults like the empty string).

[jsmeix]

Yes, I fully agree with you,
cf. your
#3025 (comment)
and my
#3025 (comment)
that reads (excerpt)

What is still questionable is if ReaR should
try to silently "correct" a user specified value
like "only blank characters" == "no characters",
...
or
if ReaR should not try to "correct" user specified values?

The more I am thinking about it the more I think that
ReaR should not try to "correct" user specified values
but error out when a user specified value is wrong.

[schlomo]

Good catch, thank you!