function newline_to_space() {
  # Replaces all newlines with spaces
  # $1: name of variable

  local -n ptr=$1
  # Replace newlines with spaces
  # See bash string substitution: https://gist.github.com/JPvRiel/b279524d3e56229a896477cb8082a72b

  # echo "replacing newlines in str: -->$ptr<--"
  ptr="${ptr//$'\n'/' '}"
  # echo "new str is: -->$ptr<--"
}

function newline_separated_to_array() {
  # Watch out for tailing newlines as these will get an empty array entry at the end.
  # $1 and $2 can be equal (if the result shall be written to the input variable)
  #
  # $1: name of variable with newline separated list
  # $2: name of array to store values into

  local -n ptr=$1
  local -n ptr2=$2
  # ptr newline separated list.
  # Store this as array ptr2.
  readarray -t ptr2 <<<"$ptr"
}

function space_separated_to_array() {
  # $1: name of variable with space separated list
  # $2: name of array to store values into

  local -n ptr=$1
  local -n ptr2=$2
  # ptr space separated list.
  # Store this as array ptr2.
  # Without newline at last array element: https://unix.stackexchange.com/a/519917/315162
  readarray -d " " -t ptr2 < <(printf '%s' "$ptr")
}




function get_block_devices() {
  # return: the following variables:
  #   BLOCK_DEVICES (array with one entry for each block device)

  # Get list of devices, one per line
  BLOCK_DEVICES=$(lsblk -dplnx size -o name | grep -Ev "boot|rpmb|loop" | tac)

  newline_separated_to_array BLOCK_DEVICES  BLOCK_DEVICES
}

function get_block_devices_with_size() {
  # return: the following variables:
  #   BLOCK_DEVICE_SIZES (array with two entries for each block device: device path and device size)

  # Get list of devices and their sizes, one pair per line
  # Use sed to remove multiple white spaces: sed 's|\s\s*| |'
  BLOCK_DEVICE_SIZES="$(lsblk -dplnx size -o name,size | grep -Ev "boot|rpmb|loop" | sed 's|\s\s*| |' | tac)"

  newline_to_space BLOCK_DEVICE_SIZES
  space_separated_to_array BLOCK_DEVICE_SIZES BLOCK_DEVICE_SIZES

#  # DEBUG
#  for i in "${BLOCK_DEVICE_SIZES[@]}"; do
#    echo "<$i>"
#  done
#  exit
}