From aff16b9f49bb5cbb49e483c09ea375759974491e Mon Sep 17 00:00:00 2001
From: Paulo Gomes <paulo.gomes@weave.works>
Date: Fri, 25 Nov 2022 17:07:34 +0000
Subject: [PATCH] build: Link libgit2 via LIB_FUZZING_ENGINE

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
---
 tests/fuzz/oss_fuzz_postbuild.sh |  6 +++++-
 tests/fuzz/oss_fuzz_prebuild.sh  | 13 ++++++++++++-
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/tests/fuzz/oss_fuzz_postbuild.sh b/tests/fuzz/oss_fuzz_postbuild.sh
index 36818fed5..2b155772e 100755
--- a/tests/fuzz/oss_fuzz_postbuild.sh
+++ b/tests/fuzz/oss_fuzz_postbuild.sh
@@ -20,10 +20,14 @@ set -euxo pipefail
 # Use it for unsetting any environment variables that may impact other building
 # processes.
 
+if [[ -n "${PRE_LIB_FUZZING_ENGINE}" ]]; then
+	export LIB_FUZZING_ENGINE="${PRE_LIB_FUZZING_ENGINE}"
+fi
+
 unset TARGET_DIR
 unset CGO_ENABLED
 unset LIBRARY_PATH
 unset PKG_CONFIG_PATH
 unset CGO_CFLAGS
 unset CGO_LDFLAGS
-unset ADDITIONAL_LIBS
+unset PRE_LIB_FUZZING_ENGINE
diff --git a/tests/fuzz/oss_fuzz_prebuild.sh b/tests/fuzz/oss_fuzz_prebuild.sh
index 29cd7d615..ac6314f55 100755
--- a/tests/fuzz/oss_fuzz_prebuild.sh
+++ b/tests/fuzz/oss_fuzz_prebuild.sh
@@ -62,4 +62,15 @@ export PKG_CONFIG_PATH="${TARGET_DIR}/lib/pkgconfig"
 export CGO_CFLAGS="-I${TARGET_DIR}/include"
 export CGO_LDFLAGS="$(pkg-config --libs --static --cflags libgit2)"
 
-export ADDITIONAL_LIBS="${TARGET_DIR}/lib/libgit2.a"
+# Temporary hack whilst libgit2 is still in use.
+# Enables the fuzzing compilation to link libgit2.
+#
+# After building the fuzzers, the value of
+# LIB_FUZZING_ENGINE is reset to what it was before
+# it to avoid side effects onto other repositories.
+#
+# For context refer to:
+# https://github.com/google/oss-fuzz/pull/9063
+export PRE_LIB_FUZZING_ENGINE="${LIB_FUZZING_ENGINE}"
+
+export LIB_FUZZING_ENGINE="${LIB_FUZZING_ENGINE} -Wl,--start-group ${TARGET_DIR}/lib/libgit2.a"