| #!/bin/bash -x |
| # Copyright 2016 The Bazel Authors. All rights reserved. |
| # |
| # 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. |
| |
| # This script collects code coverage data for C++ sources, after the tests |
| # were executed. |
| # |
| # Bazel C++ code coverage collection support is poor and limited. There is |
| # an ongoing effort to improve this (tracking issue #1118). |
| # |
| # Bazel uses the lcov tool for gathering coverage data. There is also |
| # an experimental support for clang llvm coverage, which uses the .profraw |
| # data files to compute the coverage report. |
| # |
| # This script assumes the following environment variables are set: |
| # - COVERAGE_DIR Directory containing metadata files needed for |
| # coverage collection (e.g. gcda files, profraw). |
| # - COVERAGE_MANIFEST Location of the instrumented file manifest. |
| # - COVERAGE_GCOV_PATH Location of gcov. This is set by the TestRunner. |
| # - ROOT Location from where the code coverage collection |
| # was invoked. |
| # |
| # The script looks in $COVERAGE_DIR for the C++ metadata coverage files (either |
| # gcda or profraw) and uses either lcov or gcov to get the coverage data. |
| # The coverage data is placed in $COVERAGE_OUTPUT_FILE. |
| |
| # Checks if clang llvm coverage should be used instead of lcov. |
| function uses_llvm() { |
| if stat "${COVERAGE_DIR}"/*.profraw >/dev/null 2>&1; then |
| return 0 |
| fi |
| return 1 |
| } |
| |
| # Returns 0 if gcov must be used, 1 otherwise. |
| function uses_gcov() { |
| [[ "$GCOV_COVERAGE" -eq "1" ]] && return 0 |
| return 1 |
| } |
| |
| function init_gcov() { |
| # Symlink the gcov tool such with a link called gcov. Clang comes with a tool |
| # called llvm-cov, which behaves like gcov if symlinked in this way (otherwise |
| # we would need to invoke it with "llvm-cov gcov"). |
| # For more details see https://llvm.org/docs/CommandGuide/llvm-cov.html. |
| GCOV="${COVERAGE_DIR}/gcov" |
| ln -s "${COVERAGE_GCOV_PATH}" "${GCOV}" |
| } |
| |
| # Computes code coverage data using the clang generated metadata found under |
| # $COVERAGE_DIR. |
| # Writes the collected coverage into the given output file. |
| function llvm_coverage() { |
| local output_file="${1}"; shift |
| export LLVM_PROFILE_FILE="${COVERAGE_DIR}/%h-%p-%m.profraw" |
| "${COVERAGE_GCOV_PATH}" merge -output "${output_file}" \ |
| "${COVERAGE_DIR}"/*.profraw |
| } |
| |
| # Computes code coverage data using gcda files found under $COVERAGE_DIR. |
| # Writes the collected coverage into the given output file in lcov format. |
| function lcov_coverage() { |
| local output_file="${1}"; shift |
| |
| cat "${COVERAGE_MANIFEST}" | grep ".gcno$" | while read gcno; do |
| mkdir -p "${COVERAGE_DIR}/$(dirname ${gcno})" |
| cp "${ROOT}/${gcno}" "${COVERAGE_DIR}/${gcno}" |
| done |
| |
| local lcov_tool="$(which lcov)" |
| if [[ ! -x "$lcov_tool" ]]; then |
| lcov_tool=/usr/bin/lcov |
| fi |
| |
| # Run lcov over the .gcno and .gcda files to generate the lcov tracefile. |
| # -c - Collect coverage data |
| # --no-external - Do not collect coverage data for system files |
| # --ignore-errors graph - Ignore missing .gcno files; Bazel only instruments |
| # some files |
| # -q - Quiet mode |
| # --gcov-tool "${GCOV}" - Pass the local symlink to be uses as gcov by lcov |
| # -b /proc/self/cwd - Use this as a prefix for all source files instead of |
| # the current directory |
| # -d "${COVERAGE_DIR}" - Directory to search for .gcda files |
| # -o "${COVERAGE_OUTPUT_FILE}" - Output file |
| $lcov_tool -c --no-external --ignore-errors graph \ |
| --gcov-tool "${GCOV}" -b /proc/self/cwd \ |
| -d "${COVERAGE_DIR}" -o "${output_file}" |
| |
| # Fix up the paths to be relative by removing the prefix we specified above. |
| sed -i -e "s*/proc/self/cwd/**g" "${output_file}" |
| } |
| |
| # Generates a code coverage report in gcov intermediate text format by invoking |
| # gcov and using the profile data (.gcda) and notes (.gcno) files. |
| # |
| # The profile data files are expected to be found under $COVERAGE_DIR. |
| # The notes file are expected to be found under $ROOT. |
| # |
| # - output_file The location of the file where the generated code coverage |
| # report is written. |
| function gcov_coverage() { |
| local output_file="${1}"; shift |
| |
| # We'll save the standard output of each the gcov command in this log. |
| local gcov_log="$output_file.gcov.log" |
| |
| # Copy .gcno files next to their corresponding .gcda files in $COVERAGE_DIR |
| # because gcov expects them to be in the same directory. |
| cat "${COVERAGE_MANIFEST}" | grep ".gcno$" | while read gcno_path; do |
| |
| local gcda="${COVERAGE_DIR}/$(dirname ${gcno_path})/$(basename ${gcno_path} .gcno).gcda" |
| # If the gcda file was not found we skip generating coverage from the gcno |
| # file. |
| if [[ -f "$gcda" ]]; then |
| # gcov expects both gcno and gcda files to be in the same directory. |
| # We overcome this by copying the gcno to $COVERAGE_DIR where the gcda |
| # files are expected to be. |
| if [ ! -f "${COVERAGE_DIR}/${gcno_path}" ]; then |
| mkdir -p "${COVERAGE_DIR}/$(dirname ${gcno_path})" |
| cp "$ROOT/${gcno_path}" "${COVERAGE_DIR}/${gcno_path}" |
| fi |
| # Invoke gcov to generate a code coverage report with the flags: |
| # -i Output gcov file in an intermediate text format. |
| # The output is a single .gcov file per .gcda file. |
| # No source code is required. |
| # -b Write branch frequencies to the output file, and |
| # write branch summary info to the standard output. |
| # -o directory The directory containing the .gcno and |
| # .gcda data files. |
| # "${gcda"} The input file name. gcov is looking for data files |
| # named after the input filename without its extension. |
| # gcov produces files called <source file name>.gcov in the current |
| # directory. These contain the coverage information of the source file |
| # they correspond to. One .gcov file is produced for each source |
| # (or header) file containing code which was compiled to produce the |
| # .gcda files. |
| "${GCOV}" -i -b -o "$(dirname ${gcda})" "${gcda}" &> "$gcov_log" |
| |
| # Go through all the files that were created by the gcov command above |
| # and append their content to the output .gcov file. |
| # |
| # For each source file gcov outputs to stdout something like this: |
| # |
| # File 'examples/cpp/hello-lib.cc' |
| # Lines executed:100.00% of 8 |
| # Creating 'hello-lib.cc.gcov' |
| # |
| # We grep the names of the files that were created from that output. |
| cat "$gcov_log" | grep "Creating" | cut -d " " -f 2 | cut -d"'" -f2 | \ |
| while read gcov_file; do |
| echo "Processing $gcov_file" |
| cat "$gcov_file" >> "$output_file" |
| # Remove the intermediate gcov file because it is not useful anymore. |
| rm -f "$gcov_file" |
| done |
| fi |
| done |
| } |
| |
| function main() { |
| init_gcov |
| |
| # If llvm code coverage is used, we output the raw code coverage report in |
| # the $COVERAGE_OUTPUT_FILE. This report will not be converted to any other |
| # format by LcovMerger. |
| # TODO(#5881): Convert profdata reports to lcov. |
| if uses_llvm; then |
| BAZEL_CC_COVERAGE_TOOL="PROFDATA" |
| fi |
| |
| # When using either gcov or lcov, have an output file specific to the test |
| # and format used. For lcov we generate a ".dat" output file and for gcov |
| # a ".gcov" output file. It is important that these files are generated under |
| # COVERAGE_DIR. |
| # When this script is invoked by tools/test/collect_coverage.sh either of |
| # these two coverage reports will be picked up by LcovMerger and their |
| # content will be converted and/or merged with other reports to an lcov |
| # format, generating the final code coverage report. |
| case "$BAZEL_CC_COVERAGE_TOOL" in |
| ("GCOV") gcov_coverage "$COVERAGE_DIR/_cc_coverage.gcov" ;; |
| ("LCOV") lcov_coverage "$COVERAGE_DIR/_cc_coverage.dat" ;; |
| ("PROFDATA") llvm_coverage "$COVERAGE_DIR/_cc_coverage.profdata" ;; |
| (*) echo "Coverage tool $BAZEL_CC_COVERAGE_TOOL not supported" \ |
| && exit 1 |
| esac |
| } |
| |
| main |
