test_rng_quality

#!/bin/bash

function progress {
    let "_progress = (${1} * 100 / ${2} * 100) / 100"
    let "_done = (${_progress} * 4) / 10"
    let "_left = 40 - $_done"
    _fill=$(printf "%${_done}s")
    _empty=$(printf "%${_left}s")
    printf "\r${_fill// /▇}${_empty// /-} ${_progress}%%"
}

GREEN='\033[0;32m'
RED='\033[0;31m'
NC='\033[0m'

AMOUNT=1048576

# Update opal-toolset submodule
printf "Updating opal-toolset ...\n"
git submodule update --init --remote --merge >/dev/null
( cd opal-toolset && make >/dev/null 2>&1 ) || { printf "\nBuild of opal-toolset failed, test skipped.\n" && exit 1; }

[ -z "$OPAL_RNG_PATH" ] && OPAL_RNG_PATH="opal-toolset"
RNG=$OPAL_RNG_PATH/rng
[ ! -f "$RNG" ] && printf "Invalid path $RNG, test skipped.\n" && exit 1

[ -z "$DEV" ] && printf "WARNING: Variable DEV must be defined (partition or block device), test skipped.\n" && exit 1

TMPDIR="$(mktemp -d)"
cd $TMPDIR

gcc -std=c99 -o test ${OLDPWD}/source/chi_squared_test.c || { printf "\nBuild of testing program failed, test skipped.\n" && exit 1; }

printf "Extracting 1MiB of random data ...\n"

${OLDPWD}/${RNG} $DEV -b $AMOUNT -o rng.tmp >/dev/null 2>&1 &
pid=$!
trap "kill $pid 2> /dev/null" EXIT

# Wait until the data extraction program creates output file rng.tmp
while [ ! -f rng.tmp ] && kill -0 $pid 2> /dev/null; do
    sleep 0.5
done

# Draw progress during data extraction
while kill -0 $pid 2> /dev/null; do
    RNG_CURRENT_SIZE="$(wc -c <rng.tmp)"
    progress ${RNG_CURRENT_SIZE} ${AMOUNT}
    sleep .2
done
trap - EXIT

wait $pid
if [ $? == 1 ]; then
    printf "\nRandom data extraction failed, test skipped.\n"
    exit 1
fi

# Finish progress bar on successful extraction
if [ -f rng.tmp ]; then
    RNG_CURRENT_SIZE="$(wc -c <rng.tmp)"
    progress ${RNG_CURRENT_SIZE} ${AMOUNT}
    printf "\n"
fi

if ./test rng.tmp; then
    printf "\n${GREEN}RNG OK${NC}\n"
    printf "\nQuality of the random number generator doesn't show significant deficiency.\n"
    printf "To ensure this quality holds and isn't coincidental, run this test multiple times.\n"
else
    printf "\n${RED}FATAL - quality of the random number generator is not sufficient!${NC}\n"
    RNG_OUT_FILE="${OLDPWD}/rng_output_$(basename $DEV)_$(date +"%FT%T")"
    mv rng.tmp $RNG_OUT_FILE
    printf "\nThe random sample was saved into $(basename $RNG_OUT_FILE) for further inspection.\n"
    printf "To ensure the quality holds and isn't coincidental, run this test multiple times.\n"
    exit 1
fi