task_fence.hpp

#ifndef TASK_FENCE_HPP
#define TASK_FENCE_HPP

#include <condition_variable>
#include <mutex>

class TaskFence
{
	int taskCount_;
	std::condition_variable taskCV_;
	std::mutex taskMutex_;
public:
	TaskFence() : taskCount_(0) {}
	
	~TaskFence()
	{
		wait();
	}

	void increment()
	{
		std::lock_guard<std::mutex> lock(taskMutex_);
		++taskCount_;
	}

	void decrement()
	{
		{
			std::lock_guard<std::mutex> lock(taskMutex_);
			--taskCount_;
		}
		taskCV_.notify_all();
	}

	void wait()
	{
		std::unique_lock<std::mutex> lock(taskMutex_);
		taskCV_.wait(lock, [this]{return taskCount_ == 0;});
	}
};

#endif // TASK_FENCE_HPP