#!/bin/bash -eu
# 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.
#
################################################################################

# Force Python3, run configure.py to pick the right build config
PYTHON=python3
yes "" | ${PYTHON} configure.py

# Since Bazel passes flags to compilers via `--copt`, `--conlyopt` and
# `--cxxopt`, we need to move all flags from `$CFLAGS` and `$CXXFLAGS` to these.
# We don't use `--copt` as warnings issued by C compilers when encountering a
# C++-only option results in errors during build.
#
# Note: Make sure that by this line `$CFLAGS` and `$CXXFLAGS` are properly set
# up as further changes to them won't be visible to Bazel.
#
# Note: for builds using the undefined behavior sanitizer we need to link
# `clang_rt` ubsan library. Since Bazel uses `clang` for linking instead of
# `clang++`, we need to add the additional `--linkopt` flag.
# See issue: https://github.com/bazelbuild/bazel/issues/8777
declare -r EXTRA_FLAGS="\
$(
for f in ${CFLAGS}; do
  echo "--conlyopt=${f}" "--linkopt=${f}"
done
for f in ${CXXFLAGS}; do
    echo "--cxxopt=${f}" "--linkopt=${f}"
done
if [ "$SANITIZER" = "undefined" ]
then
  echo "--linkopt=$(find $(llvm-config --libdir) -name libclang_rt.ubsan_standalone_cxx-x86_64.a | head -1)"
  sed -i -e 's/"\/\/conditions:default": \[/"\/\/conditions:default": \[\n"-fno-sanitize=undefined",/' third_party/nasm/nasm.BUILD
  sed -i -e 's/includes/linkopts = \["-fno-sanitize=undefined"\],\nincludes/' third_party/nasm/nasm.BUILD
fi
if [ "$SANITIZER" = "address" ]
then
  echo "--action_env=ASAN_OPTIONS=detect_leaks=0,detect_odr_violation=0"
fi
)"

# Ugly hack to get LIB_FUZZING_ENGINE only for fuzz targets
# and not for other binaries such as protoc
sed -i -e 's/linkstatic/linkopts = \["-fsanitize=fuzzer"\],\nlinkstatic/' tensorflow/security/fuzzing/tf_fuzzing.bzl

# Determine all fuzz targets. To control what gets fuzzed with OSSFuzz, all
# supported fuzzers are in `//tensorflow/security/fuzzing`.
# Ignore fuzzers tagged with `no_oss` in opensource.
declare FUZZERS=$(bazel query 'kind(cc_.*, tests(//tensorflow/security/fuzzing/...)) - attr(tags, no_oss, kind(cc_.*, tests(//tensorflow/security/fuzzing/...)))' | grep -v checkpoint_reader_fuzz)
# checkpoint_reader_fuzz seems out of date with the API

# Build the fuzzer targets.
# Pass in `--config=libc++` to link against libc++.
# Pass in `--verbose_failures` so it is easy to debug compile crashes.
# Pass in `--strip=never` to ensure coverage support.
# Since we have `assert` in fuzzers, make sure `NDEBUG` is not defined
bazel build \
  --config=libc++ \
  ${EXTRA_FLAGS} \
  --verbose_failures \
  --strip=never \
  --copt='-UNDEBUG' \
  -- ${FUZZERS}

# The fuzzers built above are in the `bazel-bin/` symlink. But they need to be
# in `$OUT`, so move them accordingly.
for bazel_target in ${FUZZERS}; do
  colon_index=$(expr index "${bazel_target}" ":")
  fuzz_name="${bazel_target:$colon_index}"
  bazel_location="bazel-bin/${bazel_target/:/\/}"
  cp ${bazel_location} ${OUT}/$fuzz_name
done

echo "  write_to_bazelrc('import %workspace%/tools/bazel.rc')" >> configure.py
yes "" | ./configure

declare FUZZERS=$(grep '^tf_ops_fuzz_target' tensorflow/core/kernels/fuzzing/BUILD | cut -d'"' -f2 | grep -v decode_base64)

cat >> tensorflow/core/kernels/fuzzing/tf_ops_fuzz_target_lib.bzl << END

def cc_tf(name):
    native.cc_test(
        name = name + "_fuzz",
        deps = [
            "//tensorflow/core/kernels/fuzzing:fuzz_session",
            "//tensorflow/core/kernels/fuzzing:" + name + "_fuzz_lib",
            "//tensorflow/cc:cc_ops",
            "//tensorflow/cc:scope",
            "//tensorflow/core:core_cpu",
        ],

	linkopts = ["-fsanitize=fuzzer"]
    )
END

cat >> tensorflow/core/kernels/fuzzing/BUILD << END

load("//tensorflow/core/kernels/fuzzing:tf_ops_fuzz_target_lib.bzl", "cc_tf")

END

for fuzzer in ${FUZZERS}; do
    echo cc_tf\(\"${fuzzer}\"\) >> tensorflow/core/kernels/fuzzing/BUILD
done

declare FUZZERS=$(bazel query 'kind(cc_.*, tests(//tensorflow/core/kernels/fuzzing/...))' | grep -v decode_base64)

bazel build \
  --spawn_strategy=sandboxed \
  --jobs=$(nproc) \
  --config=monolithic \
  --dynamic_mode=off \
  ${EXTRA_FLAGS} \
  --verbose_failures \
  --strip=never \
  --define=framework_shared_object=false \
  -- //tensorflow/core/kernels/fuzzing:all

# The fuzzers built above are in the `bazel-bin/` symlink. But they need to be
# in `$OUT`, so move them accordingly.
for bazel_target in ${FUZZERS}; do
  colon_index=$(expr index "${bazel_target}" ":")
  fuzz_name="${bazel_target:$colon_index}"
  bazel_location="bazel-bin/${bazel_target/:/\/}"
  cp ${bazel_location} ${OUT}/$fuzz_name
  corpus_location=tensorflow/core/kernels/fuzzing/corpus/$(basename ${fuzz_name} _fuzz)
  if [[ -d ${corpus_location} ]]
  then
    find ${corpus_location} -type f | xargs zip -j ${OUT}/${fuzz_name}_seed_corpus.zip
  fi
  dict_location=tensorflow/core/kernels/fuzzing/dictionaries/$(basename ${fuzz_name} _fuzz).dict
  if [[ -f ${dict_location} ]]
  then
    cp ${dict_location} $OUT/${fuzz_name}.dict
  fi
done

# For coverage, we need to remap source files to correspond to the Bazel build
# paths. We also need to resolve all symlinks that Bazel creates.
if [ "$SANITIZER" = "coverage" ]
then
  declare -r RSYNC_CMD="rsync -aLkR"
  declare -r REMAP_PATH=${OUT}/proc/self/cwd/
  mkdir -p ${REMAP_PATH}

  # Sync existing code.
  ${RSYNC_CMD} tensorflow/ ${REMAP_PATH}

  # Sync generated proto files.
  ${RSYNC_CMD} ./bazel-out/k8-opt/bin/tensorflow/ ${REMAP_PATH}
  ${RSYNC_CMD} ./bazel-out/k8-opt/bin/external/ ${REMAP_PATH}
  ${RSYNC_CMD} ./bazel-out/k8-opt/bin/third_party/ ${REMAP_PATH}

  # Sync external dependencies. We don't need to include `bazel-tensorflow`.
  # Also, remove `external/org_tensorflow` which is a copy of the entire source
  # code that Bazel creates. Not removing this would cause `rsync` to expand a
  # symlink that ends up pointing to itself!
  pushd bazel-tensorflow
  [[ -e external/org_tensorflow ]] && unlink external/org_tensorflow
  ${RSYNC_CMD} external/ ${REMAP_PATH}
  popd
fi

# Finally, make sure we don't accidentally run with stuff from the bazel cache.
rm -f bazel-*