From 082033d384f793004b0deef88dbb8d4f7bcd0969 Mon Sep 17 00:00:00 2001
From: saschawillems <webmaster@saschawillems.de>
Date: Fri, 1 Apr 2016 12:17:30 +0200
Subject: [PATCH] Added basic C++11 thread pool

---
 base/threadpool.hpp | 111 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 111 insertions(+)
 create mode 100644 base/threadpool.hpp

diff --git a/base/threadpool.hpp b/base/threadpool.hpp
new file mode 100644
index 00000000..c9695107
--- /dev/null
+++ b/base/threadpool.hpp
@@ -0,0 +1,111 @@
+/*
+* Basic C++11 based thread pool with per-thread job queues
+*
+* Copyright (C) 2016 by Sascha Willems - www.saschawillems.de
+*
+* This code is licensed under the MIT license (MIT) (http://opensource.org/licenses/MIT)
+*/
+
+#include <vector>
+#include <thread>
+#include <queue>
+#include <mutex>
+
+namespace vkTools
+{
+	class Thread
+	{
+	private:
+		bool destroying = false;
+		std::thread worker;
+		std::queue<std::function<void()>> jobQueue;
+		std::mutex queueMutex;
+		std::condition_variable condition;
+
+		// Loop through all remaining jobs
+		void queueLoop()
+		{
+			while (true)
+			{
+				std::function<void()> job;
+				{
+					std::unique_lock<std::mutex> lock(queueMutex);
+					condition.wait(lock, [this] { return !jobQueue.empty() || destroying; });
+					if (destroying)
+					{
+						break;
+					}
+					job = jobQueue.front();
+				}
+
+				job();
+
+				{
+					std::lock_guard<std::mutex> lock(queueMutex);
+					jobQueue.pop();
+					condition.notify_one();
+				}
+			}
+		}
+
+	public:
+		Thread()
+		{
+			worker = std::thread(&Thread::queueLoop, this);
+		}
+
+		~Thread()
+		{
+			if (worker.joinable())
+			{
+				wait();
+				queueMutex.lock();
+				destroying = true;
+				condition.notify_one();
+				queueMutex.unlock();
+				worker.join();
+			}
+		}
+
+		// Add a new job to the thread's queue
+		void addJob(std::function<void()> function)
+		{
+			std::lock_guard<std::mutex> lock(queueMutex);
+			jobQueue.push(std::move(function));
+			condition.notify_one();
+		}
+
+		// Wait until all work items have been finished
+		void wait()
+		{
+			std::unique_lock<std::mutex> lock(queueMutex);
+			condition.wait(lock, [this]() { return jobQueue.empty(); });
+		}
+	};
+	
+	class ThreadPool
+	{
+	public:
+		std::vector<std::unique_ptr<Thread>> threads;
+
+		// Sets the number of threads to be allocted in this pool
+		void setThreadCount(uint32_t count)
+		{
+			threads.clear();
+			for (auto i = 0; i < count; i++)
+			{
+				threads.push_back(std::make_unique<Thread>());
+			}
+		}
+
+		// Wait until all threads have finished their work items
+		void wait()
+		{
+			for (auto &thread : threads)
+			{
+				thread->wait();
+			}
+		}
+	};
+
+}
\ No newline at end of file