#!/bin/sh -eu

# As a first step see README.md and follow the steps under "Running a fuzzer using clang".

# You might need 'gsutil' to download new corpora from the Google cloud:
# Read the docs at https://github.com/google/oss-fuzz/blob/master/docs/corpora.md
# then install 'google-cloud-sdk' and execute 'gcloud init'.
# Now 'gsutil' should be ready to use.

if test -z "$1"; then
  echo "Usage: $0 <fuzzer target>"
  echo "Example: $0 libpsl_fuzzer"
  exit 1
fi

if ! grep -q FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION Makefile; then
  echo "The fuzzers haven't been built for fuzzing (maybe for regression testing !?)"
  echo "Please built regarding README.md and try again."
  exit 1
fi

fuzzer=$1
project=$(echo $1 | cut -d'_' -f1)

# sync/copy the OSS-Fuzz corpora into the .new directory
mkdir -p ${fuzzer}.in ${fuzzer}.new
cp -fp ${fuzzer}.in/* ${fuzzer}.new 2>/dev/null || true
gsutil cp $(gsutil ls gs://${project}-backup.clusterfuzz-external.appspot.com/corpus/libFuzzer/${fuzzer}|tail -n 1) ${fuzzer}.new/
(cd ${fuzzer}.new && unzip -o *.zip && mv *.zip ..)

# create fuzzer target
BUILD_ONLY=1 ./run-clang.sh ${fuzzer}

# merge the corpora into the .in directory
./${fuzzer} -merge=1 ${fuzzer}.in ${fuzzer}.new

# now clear .new dir and put all corpora there
rm -rf ${fuzzer}.new
mv ${fuzzer}.in ${fuzzer}.new
mkdir ${fuzzer}.in

# now merge again (optimizes number of corpora)
./${fuzzer} -merge=1 ${fuzzer}.in ${fuzzer}.new

echo
echo "If new files have been added, 'git add' and 'git commit' them."