add quick flash script

build/quick-flash.sh

@@ -0,0 +1,35 @@
+#!/bin/bash
+
+set -e
+
+echo 'This script will only work on a card that has previously had a full image written to it.'
+echo 'It will *only* flash the ext4 portion (`green` partition) of the img file onto the card.'
+echo 'The product key, disk guid, and kernel data will *not* be affected.'
+read -p "Continue? [y/N]" -n 1 -r
+if ! [[ "$REPLY" =~ ^[Yy]$ ]]; then
+        exit 1
+else
+	echo
+fi
+
+if ! test -e /dev/disk/by-label/green; then
+	>&2 echo '`green` partition not found'
+	exit 1
+fi
+
+export SOURCE_DEVICE=$(sudo losetup --show -fP eos.img)
+sudo e2fsck -f ${SOURCE_DEVICE}p3
+sudo resize2fs -M ${SOURCE_DEVICE}p3
+export BLOCK_INFO=$(sudo dumpe2fs ${SOURCE_DEVICE}p3)
+export BLOCK_COUNT=$(echo "$BLOCK_INFO" | grep "Block count:" | sed 's/Block count:\s\+//g')
+export BLOCK_SIZE=$(echo "$BLOCK_INFO" | grep "Block size:" | sed 's/Block size:\s\+//g')
+sudo dd if=${SOURCE_DEVICE}p3 of=/dev/disk/by-label/green count=$BLOCK_COUNT bs=$BLOCK_SIZE status=progress
+echo Verifying...
+export INPUT_HASH=$(sudo dd if=${SOURCE_DEVICE}p3 count=$BLOCK_COUNT bs=$BLOCK_SIZE | sha256sum)
+export OUTPUT_HASH=$(sudo dd if=/dev/disk/by-label/green count=$BLOCK_COUNT bs=$BLOCK_SIZE | sha256sum)
+sudo losetup -d ${SOURCE_DEVICE}
+if ! [[ "$INPUT_HASH" == "$OUTPUT_HASH" ]]; then
+	>&2 echo Verification Failed
+	exit 1
+fi
+echo Quick Flash Successfull