#!/system/bin/sh -ex

ITERATION="$1"
OUTPUT="$2"
PARTITION="$3"
export PATH="/data/local/tmp/bin:${PATH}"

if [ "$#" -lt 2 ]; then
    echo "ERROR: Usage: $0 <iteration> <output> <partition>"
    exit 1
fi

[ -d "${OUTPUT}" ] && mv "${OUTPUT}" "${OUTPUT}_$(date -r "${OUTPUT}" +%Y%m%d%H%M%S)"
mkdir -p "${OUTPUT}" && cd "${OUTPUT}"

# If partition specified, format it to vfat, and mount it to /mnt/dd_test.
# Then enter the mount point to do dd test.
if [ -n "${PARTITION}" ]; then
    partition_name=$(basename "${PARTITION}")
    # shellcheck disable=SC2016
    partition_numbers=$(grep "${partition_name}" /proc/partitions | busybox awk '{print $1","$2}')

    if [ -z "${partition_numbers}" ]; then
        echo "ERROR: ${PARTITION} NOT found" && exit 1
    else
        # Attemp to umount it in case it is mounted by Android vold.
        umount "/dev/block/vold/public:${partition_numbers}" > /dev/null 2>&1 || true
        umount "${PARTITION}" > /dev/null 2>&1 || true

        echo "INFO: formatting ${PARTITION} to vfat..."
        busybox mkfs.vfat "${PARTITION}"
        sync && sleep 10

        mkdir -p /mnt/dd_test
        if mount -t vfat "${PARTITION}" /mnt/dd_test/; then
            echo "INFO: Mounted ${PARTITION} to /mnt/dd_test"
        else
            echo "ERROR: failed to mount ${PARTITION}" && exit 1
        fi

        cd /mnt/dd_test
        echo "INFO: dd test directory: $(pwd)"
    fi
fi

# Run dd write/read test.
for i in $(seq "${ITERATION}"); do
    echo
    echo "INFO: Running dd write test [$i/${ITERATION}]"
    echo 3 > /proc/sys/vm/drop_caches
    busybox dd if=/dev/zero of=dd.img bs=1048576 count=1024 conv=fsync 2>&1 \
        | tee  -a "${OUTPUT}"/dd-write-output.txt

    echo
    echo "INFO: Running dd read test [$i/${ITERATION}]"
    echo 3 > /proc/sys/vm/drop_caches
    busybox dd if=dd.img of=/dev/null bs=1048576 count=1024 2>&1 \
        | tee -a "${OUTPUT}"/dd-read-output.txt

    rm -f dd.img
done