Use rooted Android phone to write Raspberry Pi image to microSSD card

write_sd_image

#!/bin/bash
# Use a rooted android phone to load a raspberry pi image onto a microSSD card.
#
# adb push /dev/block/$PHONEBLOCKDEVICE
# won't work because you are not root by default
#
# Commands like
# cat $IMAGEFILE | adb su -c dd of=/dev/block/$PHONEBLOCKDEVICE
# won't work because adb corrupts the stream
#
# adb push $IMAGEFILE /path/to/writable/memory/image
# won't work unless your phone can fit the im#!/bin/bash
#
# You need a script to copy the file in many chunks

#!/bin/bash

IMAGEFILE=$1
PHONEBLOCKDEVICE=$2
BS=1048576
STEP=16

usage () {
  echo "write_sd_image IMAGEFILE PHONEBLOCKDEVICE"
  exit
}

if [[ -z "$IMAGEFILE" ]]
then
  echo "Please supply IMAGEFILE"
  usage
fi


if [[ -z "$PHONEBLOCKDEVICE" ]]
then
  echo "Please supply PHONEBLOCKDEVICE"
  usage
fi

LOCATION=0
CHUNK_ID=0

while true
do

CHUNK="$IMAGEFILE.$CHUNK_ID"

echo "Writing chunk $CHUNK_ID, location $LOCATION"
echo "dd if=$IMAGEFILE of=$CHUNK skip=$(($LOCATION/$BS)) count=$STEP bs=$BS"

dd if=$IMAGEFILE of=$CHUNK skip=$(($LOCATION/$BS)) count=$STEP bs=$BS

if [[ ! -s "$CHUNK" ]]
then
  echo "complete"
  exit(0)
fi

adb push $CHUNK /mnt/sdcard/$CHUNK
rm $CHUNK

adb shell su -c "busybox dd if=/mnt/sdcard/$CHUNK of=/dev/block/$PHONEBLOCKDEVICE seek=$(($LOCATION/$BS)) count=$STEP bs=$BS"

adb shell su -c "busybox rm /mnt/sdcard/$CHUNK"

CHUNK_ID=$(($CHUNK_ID+1))
LOCATION=$(($LOCATION+$STEP*$BS))

done