feat add thread_pool

include/sled/system/thread_pool.h

@@ -0,0 +1,34 @@
+#pragma once
+#ifndef SLED_SYSTEM_THREAD_POOL_H
+#define SLED_SYSTEM_THREAD_POOL_H
+#include "sled/system/fiber/scheduler.h"
+#include <functional>
+#include <future>
+
+namespace sled {
+class ThreadPool final {
+public:
+    /**
+    * @param num_threads The number of threads to create in the thread pool. If
+    * -1, the number of threads will be equal to the number of hardware threads
+    **/
+    ThreadPool(int num_threads = -1);
+    ~ThreadPool();
+
+    template<typename F, typename... Args>
+    auto submit(F &&f, Args &&...args) -> std::future<decltype(f(args...))>
+    {
+        std::function<decltype(f(args...))()> func =
+            std::bind(std::forward<F>(f), std::forward<Args>(args)...);
+        auto task_ptr =
+            std::make_shared<std::packaged_task<decltype(f(args...))()>>(func);
+        scheduler->enqueue(marl::Task([task_ptr]() { (*task_ptr)(); }));
+        return task_ptr->get_future();
+    }
+
+private:
+    sled::Scheduler *scheduler;
+};
+
+}// namespace sled
+#endif// SLED_SYSTEM_THREAD_POOL_H