scripts: add code coverage script

Fixes: #6507

Signed-off-by: Songqian Li <sionli@tencent.com>

scripts/run_coverage.sh

@@ -0,0 +1,63 @@
+#!/usr/bin/env bash
+
+set -x
+
+# shellcheck source=/dev/null
+source "$HOME"/.cargo/env
+
+PROJECT_DIR="/cloud-hypervisor"
+TARGET_DIR="$PROJECT_DIR/target"
+
+pushd $PROJECT_DIR || exit
+
+export BUILD_TARGET=${BUILD_TARGET-$(uname -m)-unknown-linux-gnu}
+
+# GLIBC > 2.31
+GRCOV_RELEASE_URL="https://github.com/mozilla/grcov/releases/download/v0.8.19/grcov-$BUILD_TARGET.tar.bz2"
+wget --quiet "$GRCOV_RELEASE_URL" || exit 1
+tar -xjf "grcov-$BUILD_TARGET.tar.bz2"
+
+rustup component add llvm-tools-preview
+
+export_lcov() {
+    rm "coverage.info"
+
+    ./grcov "$(find . -name 'ch-*.profraw' -print)" -s . \
+        --ignore "tests/*" \
+        --ignore "test_infra/*" \
+        --ignore "performance-metrics/*" \
+        --binary-path "$TARGET_DIR/$BUILD_TARGET/release/" \
+        --branch --ignore-not-existing -t lcov \
+        -o "coverage.info"
+
+    find . -type f -name 'ch-*.profraw' -exec rm {} \;
+}
+
+# Generate HTML report
+export_html() {
+    OUTPUT_DIR="$TARGET_DIR/coverage"
+    rm -rf $OUTPUT_DIR
+    ./grcov "$(find . -name 'ch-*.profraw' -print)" -s . \
+        --ignore "tests/*" \
+        --ignore "test_infra/*" \
+        --ignore "performance-metrics/*" \
+        --binary-path "$TARGET_DIR/$BUILD_TARGET/release/" \
+        --branch --ignore-not-existing -t html \
+        -o $OUTPUT_DIR
+    find . -type f -name 'ch-*.profraw' -exec rm {} \;
+}
+
+# $1 is now a command name. Check if it is a valid command and, if so,
+# run it.
+#
+declare -f "export_$1" >/dev/null
+code=$?
+[[ $code == 0 ]] || echo "Unknown command: $1. Only support \"lcov\" and \"html\". Change to default command: html"
+type=${1-html}
+
+func=export_$type
+shift
+
+$func "$@"
+
+popd || exit 1