chore: import upstream snapshot with attribution

test/fuzzing/fuzz_butil.cpp

@@ -0,0 +1,52 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you 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.
+
+#include "butil/base64.h"
+#include "butil/crc32c.h"
+#include "butil/hash.h"
+#include "butil/sha1.h"
+
+#define kMinInputLength 5
+#define kMaxInputLength 1024
+
+extern "C" int
+LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
+{
+    if (size < kMinInputLength || size > kMaxInputLength){
+        return 1;
+    }
+
+    std::string input(reinterpret_cast<const char*>(data), size);
+
+    {
+        std::string encoded;
+        std::string decoded;
+        butil::Base64Encode(input, &encoded);
+        butil::Base64Decode(input, &decoded);
+    }
+    {
+        butil::crc32c::Value(reinterpret_cast<const char*>(data), size);
+    }
+    {
+        butil::Hash(input);
+    }
+    {
+        butil::SHA1HashString(input);
+    }
+
+    return 0;
+}