Add atomic signal implementation

include/sta/atomic_signal.hpp

@@ -0,0 +1,27 @@
+#ifndef STA_ATOMIC_SIGNAL_HPP
+#define STA_ATOMIC_SIGNAL_HPP
+
+#include <sta/signal.hpp>
+
+#include <atomic>
+
+
+namespace sta
+{
+	class AtomicSignal : public Signal
+	{
+	public:
+		AtomicSignal();
+
+		void notify() override;
+		bool peek() override;
+		bool test() override;
+		void wait() override;
+
+	private:
+		std::atomic<bool> signal_;
+	};
+} // namespace sta
+
+
+#endif // STA_ATOMIC_SIGNAL_HPP