rustls: fix coverage build (#6852)

* rustls: fix coverage build

* rustls: copy over the py script

projects/rustls/Dockerfile

@@ -16,9 +16,17 @@
 
 FROM gcr.io/oss-fuzz-base/base-builder-rust
 RUN apt-get update && apt-get install -y make autoconf automake libtool curl cmake python llvm-dev libclang-dev clang
+RUN apt-get --yes update \
+   && apt-get install --no-install-recommends --yes \
+   libssl-dev \
+   pkg-config \
+   python \
+   && apt-get clean \
+   && rm --recursive --force /var/lib/apt/lists/*
 
 RUN git clone https://github.com/ctz/rustls
 
 WORKDIR $SRC
 
 COPY build.sh $SRC/
+COPY *.py $SRC/

projects/rustls/build.sh

@@ -15,6 +15,14 @@
 #
 ################################################################################
 
+if [ "$SANITIZER" = "coverage" ]
+then
+  export RUSTFLAGS="$RUSTFLAGS -C debug-assertions=no"
+  chmod +x $SRC/rustc.py
+  export RUSTC="$SRC/rustc.py"
+  export CFLAGS=""
+fi
+
 cd $SRC/rustls
 cargo fuzz build -O
 cp fuzz/target/x86_64-unknown-linux-gnu/release/client $OUT/

projects/rustls/rustc.py

@@ -0,0 +1,28 @@
+#!/usr/bin/env python
+
+# Copyright 2021 Google LLC
+#
+# 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.
+
+import sys
+import subprocess
+
+#Disable coverage for troubling crates.
+sys.argv[0] = "rustc"
+if "tokio_util" in sys.argv or "hyper" in sys.argv:
+    try:
+        sys.argv.remove("-Zinstrument-coverage")
+    except:
+        pass
+    print(sys.argv)
+subprocess.call(sys.argv)