#!/bin/bash -u
# Copyright 2018 Google Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
################################################################################
cd $OUT

LOGS_DIR="$OUT/logs"
mkdir -p $LOGS_DIR

# This will be used by llvm-cov command to generate the actual report.
objects=""

# Number of CPUs available, this is needed for running tests in parallel.
NPROC=$(nproc)

function run_fuzz_target {
  local target=$1

  # Use 100s timeout instead of 25s as code coverage builds can be very slow.
  local args="-timeout=100 -runs=0 /corpus/${target}"

  LLVM_PROFILE_FILE="$target.profraw" $target $args &> $LOGS_DIR/$target.log
  if (( $? != 0)); then
    echo "Error occured while running $target:"
    cat $LOGS_DIR/$target.log
  fi
}

# Run each fuzz target, generate raw coverage dumps.
for fuzz_target in $(find . -maxdepth 1 -type f -executable); do
  echo "Running $fuzz_target"
  run_fuzz_target $fuzz_target &
  objects="$objects -object=$fuzz_target"

  # Do not spawn more processes than the number of CPUs available.
  n_child_proc=$(jobs -rp | wc -l)
  while [ "$n_child_proc" -eq "$NPROC" ]; do
    sleep 4
    n_child_proc=$(jobs -rp | wc -l)
  done
done

# Wait for background processes to finish.
wait

# Merge all raw dumps.
llvm-profdata merge -sparse *.profraw -o merged.profdata

# Delete unnecessary and (potentially) large .profraw files.
rm *.profraw

# TODO(mmoroz): add script from Chromium for rendering directory view reports.

# Generate HTML report.
llvm-cov show -format=html -output-dir=report -path-equivalence="/,$OUT" \
		-instr-profile merged.profdata $objects

# Serve the report locally.
echo "Serving the report on http://127.0.0.1:$HTTP_PORT/"
cd report
python3 -m http.server $HTTP_PORT