Github user achristianson commented on a diff in the pull request:
https://github.com/apache/nifi-minifi-cpp/pull/163#discussion_r148547924
--- Diff: extensions/script/lua/LuaBaseStream.cpp ---
@@ -0,0 +1,73 @@
+/**
+ *
+ * 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 <stdexcept>
+#include <memory>
+#include <utility>
+#include <string>
+
+#include "LuaBaseStream.h"
+
+namespace org {
+namespace apache {
+namespace nifi {
+namespace minifi {
+namespace lua {
+
+LuaBaseStream::LuaBaseStream(std::shared_ptr<io::BaseStream> stream)
+ : stream_(std::move(stream)) {
+}
+
+std::string LuaBaseStream::read(size_t len) {
+ if (len == 0) {
+ len = stream_->getSize();
+ }
+
+ if (len <= 0) {
+ return nullptr;
+ }
+
+ std::string buffer;
+ buffer.resize(len);
+
+ // Here, we write directly to the string data, which is safe starting in
C++ 11:
+ //
+ // The char-like objects in a basic_string object shall be stored
contiguously. That is, for any basic_string
+ // object s, the identity &*(s.begin() + n) == &*s.begin() + n shall
hold for all values of n such that
+ // 0 <= n < s.size()."
+ //
+ // http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3337.pdf
--- End diff --
Based on everything I have read, we are 100% safe here -- 14 is required
for lua, and that's well beyond when this guarantee was in the standard.
---
