Copy and unpack an .xz image to a block device - linux

copy-to-card.sh

#!/bin/sh -x

usage() {
        echo "Usage:"
        echo "$0 <url to .xz image> <device e.g. /dev/sda>"
        echo ""
        echo "Warning: Make sure you pass the device you really want to overwrite."
        echo "\tit will get wiped."
}

# Check that we have 2 arguments
if [ -z "$1" ] || [ -z "$2" ]; then
        usage
fi

# Preparing the image details
URL=$1
DISK=$2

curl -L -O "$URL"
XZ=${URL##*/}
## Unpack it and keep the xz
unxz --keep $XZ

IMAGE=$(basename "$XZ" .xz)
SIZE=$(find "$PWD/$IMAGE" -printf "%s")

## Copy it to the sdcard on /dev/sda
sudo /bin/sh -c "dd if=$IMAGE ibs=1M status=none | pv -s "$SIZE" | dd of="$DISK" obs=1M oflag=direct status=none"

## Remove the uncompressed image
#rm $IMAGE