7 files changed, 196 insertions, 0 deletions
diff --git a/contrib/catch2/fuzzing/CMakeLists.txt b/contrib/catch2/fuzzing/CMakeLists.txt
new file mode 100644
index 0000000..daba61d
--- /dev/null
+++ b/contrib/catch2/fuzzing/CMakeLists.txt
@@ -0,0 +1,20 @@
+# License: Boost 1.0
+# By Paul Dreik 2020
+
+# add a library that brings in the main() function from libfuzzer
+# and has all the dependencies, so the individual fuzzers can be
+# added one line each.
+add_library(fuzzhelper NullOStream.h NullOStream.cpp)
+target_link_libraries(fuzzhelper PUBLIC Catch2::Catch2)
+
+# use C++17 so we can get string_view
+target_compile_features(fuzzhelper PUBLIC cxx_std_17)
+
+# This should be possible to set from the outside to be oss-fuzz compatible,
+# fix later. For now, target libFuzzer only.
+target_link_options(fuzzhelper PUBLIC "-fsanitize=fuzzer")
+
+foreach(fuzzer TestSpecParser XmlWriter textflow)
+add_executable(fuzz_${fuzzer} fuzz_${fuzzer}.cpp)
+target_link_libraries(fuzz_${fuzzer} PRIVATE fuzzhelper)
+endforeach()
diff --git a/contrib/catch2/fuzzing/NullOStream.cpp b/contrib/catch2/fuzzing/NullOStream.cpp
new file mode 100644
index 0000000..e3a181e
--- /dev/null
+++ b/contrib/catch2/fuzzing/NullOStream.cpp
@@ -0,0 +1,18 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+#include "NullOStream.h"
+
+void NullOStream::avoidOutOfLineVirtualCompilerWarning()
+{
+}
+
+int NullStreambuf::overflow(int c){
+    setp(dummyBuffer, dummyBuffer + sizeof(dummyBuffer));
+    return (c == traits_type::eof()) ? '\0' : c;
+}
diff --git a/contrib/catch2/fuzzing/NullOStream.h b/contrib/catch2/fuzzing/NullOStream.h
new file mode 100644
index 0000000..abbec09
--- /dev/null
+++ b/contrib/catch2/fuzzing/NullOStream.h
@@ -0,0 +1,28 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+#pragma once
+
+#include <ostream>
+#include <streambuf>
+
+// from https://stackoverflow.com/a/8244052
+class NullStreambuf : public std::streambuf {
+  char dummyBuffer[64];
+
+protected:
+  virtual int overflow(int c) override final;
+};
+
+class NullOStream final : private NullStreambuf, public std::ostream {
+public:
+  NullOStream() : std::ostream(this) {}
+  NullStreambuf *rdbuf() { return this; }
+  virtual void avoidOutOfLineVirtualCompilerWarning();
+};
+
diff --git a/contrib/catch2/fuzzing/build_fuzzers.sh b/contrib/catch2/fuzzing/build_fuzzers.sh
new file mode 100755
index 0000000..9788c68
--- /dev/null
+++ b/contrib/catch2/fuzzing/build_fuzzers.sh
@@ -0,0 +1,33 @@
+#!/bin/sh
+#
+# Builds the fuzzers
+#
+# By Paul Dreik 20200923
+set -exu
+
+CATCHROOT=$(readlink -f $(dirname $0)/..)
+
+
+BUILDDIR=$CATCHROOT/build-fuzzers
+mkdir -p $BUILDDIR
+cd $BUILDDIR
+
+if which /usr/lib/ccache/clang++ >/dev/null 2>&1 ; then
+ CXX=/usr/lib/ccache/clang++
+else
+ CXX=clang++
+fi
+
+cmake $CATCHROOT \
+  -DCMAKE_CXX_COMPILER=$CXX \
+  -DCMAKE_CXX_FLAGS="-fsanitize=fuzzer-no-link,address,undefined -O3 -g" \
+  -DCATCH_DEVELOPMENT_BUILD=On \
+  -DCATCH_BUILD_EXAMPLES=Off \
+  -DCATCH_BUILD_EXTRA_TESTS=Off \
+  -DCATCH_BUILD_TESTING=Off \
+  -DBUILD_TESTING=Off \
+  -DCATCH_ENABLE_WERROR=Off \
+  -DCATCH_BUILD_FUZZERS=On
+
+cmake --build . -j $(nproc)
+
diff --git a/contrib/catch2/fuzzing/fuzz_TestSpecParser.cpp b/contrib/catch2/fuzzing/fuzz_TestSpecParser.cpp
new file mode 100644
index 0000000..3aba8c8
--- /dev/null
+++ b/contrib/catch2/fuzzing/fuzz_TestSpecParser.cpp
@@ -0,0 +1,22 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+//By Paul Dreik 2020
+
+#include <catch2/internal/catch_test_spec_parser.hpp>
+#include <catch2/internal/catch_tag_alias_registry.hpp>
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+
+    Catch::TagAliasRegistry tar;
+    Catch::TestSpecParser tsp(tar);
+
+    std::string buf(Data,Data+Size);
+    tsp.parse(buf);
+
+    return 0;
+}
diff --git a/contrib/catch2/fuzzing/fuzz_XmlWriter.cpp b/contrib/catch2/fuzzing/fuzz_XmlWriter.cpp
new file mode 100644
index 0000000..70c4ed8
--- /dev/null
+++ b/contrib/catch2/fuzzing/fuzz_XmlWriter.cpp
@@ -0,0 +1,22 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+//By Paul Dreik 2020
+
+#include <catch2/internal/catch_xmlwriter.hpp>
+
+#include "NullOStream.h"
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+
+    std::string buf(Data,Data+Size);
+    NullOStream nul;
+    Catch::XmlEncode encode(buf);
+    encode.encodeTo(nul);
+    return 0;
+}
+
diff --git a/contrib/catch2/fuzzing/fuzz_textflow.cpp b/contrib/catch2/fuzzing/fuzz_textflow.cpp
new file mode 100644
index 0000000..7000f42
--- /dev/null
+++ b/contrib/catch2/fuzzing/fuzz_textflow.cpp
@@ -0,0 +1,53 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+//By Paul Dreik 2020
+
+#include <catch2/internal/catch_textflow.hpp>
+
+#include "NullOStream.h"
+
+#include <string>
+#include <string_view>
+
+
+template<class Callback>
+void split(const char *Data, size_t Size, Callback callback) {
+
+    using namespace std::literals;
+    constexpr auto sep="\n~~~\n"sv;
+
+    std::string_view remainder(Data,Size);
+    for (;;) {
+        auto pos=remainder.find(sep);
+        if(pos==std::string_view::npos) {
+            //not found. use the remainder and exit
+            callback(remainder);
+            return;
+        } else {
+            //found. invoke callback on the first part, then proceed with the rest.
+            callback(remainder.substr(0,pos));
+            remainder=remainder.substr(pos+sep.size());
+        }
+    }
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+
+    Catch::TextFlow::Columns columns;
+
+    // break the input on separator
+    split((const char*)Data,Size,[&](std::string_view word) {
+        columns+=Catch::TextFlow::Column(std::string(word));
+    });
+
+    NullOStream nul;
+    nul << columns;
+
+    return 0;
+}
+