[GitHub] [nifi-minifi-cpp] arpadboda commented on a change in pull request #746: MINIFICPP-1185 - Remove moodycamel::concurrentqueue from threadpool

[GitBox <gi...@apache.org>]

arpadboda commented on a change in pull request #746: MINIFICPP-1185 - Remove moodycamel::concurrentqueue from threadpool
URL: https://github.com/apache/nifi-minifi-cpp/pull/746#discussion_r396710845
 
 

 ##########
 File path: libminifi/include/utils/ConcurrentQueue.h
 ##########
 @@ -0,0 +1,155 @@
+/**
+ * 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.
+ */
+#ifndef LIBMINIFI_INCLUDE_CONCURRENT_QUEUE_H
+#define LIBMINIFI_INCLUDE_CONCURRENT_QUEUE_H
+
+#include <deque>
+#include <mutex>
+#include <condition_variable>
+
+namespace org {
+namespace apache {
+namespace nifi {
+namespace minifi {
+namespace utils {
+
+template <typename T>
+class ConcurrentQueue {
+ public:    
+  ConcurrentQueue() = default;
+  virtual ~ConcurrentQueue() = default;
+
+  ConcurrentQueue(const ConcurrentQueue& other) = delete;
+  ConcurrentQueue& operator=(const ConcurrentQueue& other) = delete;
+  ConcurrentQueue(ConcurrentQueue&& other)
+    : ConcurrentQueue(std::move(other), std::lock_guard<std::mutex>(other.mutex_)) {}
+
+  ConcurrentQueue& operator=(ConcurrentQueue&& other) {
+    if (this != &other) {
+      std::lock(mtx_, other.mtx_);
+      std::lock_guard<std::mutex> lk1(mtx_, std::adopt_lock);
+      std::lock_guard<std::mutex> lk2(other.mtx_, std::adopt_lock);
+      queue_.swap(other.queue_);
+    }
+    return *this;
+  }
+
+  virtual bool tryDequeue(T& out) {
+    std::unique_lock<std::mutex> lck(mtx_);
+    return tryDequeue(lck, out);
+  }
+
+  virtual bool empty() const {
+    std::lock_guard<std::mutex> guard(mtx_);
+    return queue_.empty();
+  }
+
+  virtual size_t size() const {
+    std::lock_guard<std::mutex> guard(mtx_);
+    return queue_.size();
+  }
+
+  virtual void clear() {
+    std::lock_guard<std::mutex> guard(mtx_);
+    queue_.clear();
+  }
+
+  template <typename... Args>
+  void enqueue(Args&&... args) {
+    std::lock_guard<std::mutex> guard(mtx_);
+    queue_.emplace_back(std::forward<Args>(args)...);
+  }
+
+ private:
+   ConcurrentQueue(ConcurrentQueue&& other, std::lock_guard<std::mutex>&)
+    : queue_( std::move(other.queue_) ) {}
+
+ protected:
+  bool tryDequeue(std::unique_lock<std::mutex>& lck, T& out) {
+    if (!lck.owns_lock()) {
+      return false;
+    }
+    if (queue_.empty()) {
+      return false;
+    }
+    out = std::move(queue_.front());
+    queue_.pop_front();
+    return true;
+  }
+  std::deque<T> queue_;
+  mutable std::mutex mtx_;
+};
+
+template <typename T>
+class ConditionConcurrentQueue : public ConcurrentQueue<T> {
+ public:
+  ConditionConcurrentQueue(bool start = false) : ConcurrentQueue<T>(), running_{start} {};
+  
+  ConditionConcurrentQueue(const ConditionConcurrentQueue& other) = delete;
+  ConditionConcurrentQueue& operator=(const ConditionConcurrentQueue& other) = delete;
+  ConditionConcurrentQueue(ConditionConcurrentQueue&& other) = delete;
+  ConditionConcurrentQueue& operator=(ConditionConcurrentQueue&& other) = delete;
+  
+  template <typename... Args>
+  void enqueue(Args&&... args) {
+    ConcurrentQueue<T>::enqueue(std::forward<Args>(args)...);
+    if (running_) {
+      cv_.notify_one();
+    }
+  }
+  
+  bool tryDequeue(T& out) override {
 
 Review comment:
   Renamed to "dequeue", tryDequeue is also available as a non-blocking alternative. 

----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
users@infra.apache.org


With regards,
Apache Git Services