Prepare fuzzing engine

src/fuzzing-engine/fuzzer.cpp

@@ -0,0 +1,114 @@
+#include "fuzzer.hpp"
+#include "input_generator.hpp"
+
+namespace fuzzer
+{
+	namespace
+	{
+		class fuzzing_context
+		{
+		public:
+			fuzzing_context(input_generator& generator, fuzzing_handler& handler)
+				: generator(generator)
+				  , handler(handler)
+			{
+			}
+
+			void stop()
+			{
+				this->stop_ = true;
+			}
+
+			bool should_stop()
+			{
+				if (this->stop_)
+				{
+					return true;
+				}
+
+				if (!handler.stop())
+				{
+					return false;
+				}
+
+				this->stop_ = true;
+				return true;
+			}
+
+			input_generator& generator;
+			fuzzing_handler& handler;
+
+		private:
+			std::atomic_bool stop_{false};
+		};
+
+		void perform_fuzzing_iteration(const fuzzing_context& context)
+		{
+			context.generator.access_input([&](const std::span<const uint8_t> input)
+			{
+				uint64_t score{0};
+				context.handler.execute(input, [&](uint64_t)
+				{
+					++score;
+				});
+
+				return score;
+			});
+		}
+
+		void worker(fuzzing_context& context)
+		{
+			while (!context.should_stop())
+			{
+				perform_fuzzing_iteration(context);
+			}
+		}
+
+		struct worker_pool
+		{
+			fuzzing_context* context_{nullptr};
+			std::vector<std::thread> workers_{};
+
+			worker_pool(fuzzing_context& context, const size_t concurrency)
+				: context_(&context)
+			{
+				this->workers_.reserve(concurrency);
+
+				for (size_t i = 0; i < concurrency; ++i)
+				{
+					this->workers_.emplace_back([&context]
+					{
+						worker(context);
+					});
+				}
+			}
+
+			~worker_pool()
+			{
+				if (this->workers_.empty())
+				{
+					return;
+				}
+
+				this->context_->stop();
+
+				for (auto& w : this->workers_)
+				{
+					w.join();
+				}
+			}
+		};
+	}
+
+	void run(fuzzing_handler& handler, const size_t concurrency)
+	{
+		input_generator generator{};
+		fuzzing_context context{generator, handler};
+		worker_pool pool{context, concurrency};
+
+		while (!context.should_stop())
+		{
+			std::this_thread::sleep_for(std::chrono::seconds{1});
+		}
+	}
+}