Converting thread entrypoint from lamda to nano::thread_runner::run. (#4147)

nano/lib/threading.cpp

@@ -142,16 +142,44 @@ void nano::thread_attributes::set (boost::thread::attributes & attrs)
 	attrs_l->set_stack_size (8000000); // 8MB
 }
 
-nano::thread_runner::thread_runner (boost::asio::io_context & io_ctx_a, unsigned service_threads_a) :
+nano::thread_runner::thread_runner (boost::asio::io_context & io_ctx_a, unsigned num_threads) :
 	io_guard (boost::asio::make_work_guard (io_ctx_a))
 {
 	boost::thread::attributes attrs;
 	nano::thread_attributes::set (attrs);
-	for (auto i (0u); i < service_threads_a; ++i)
+	for (auto i (0u); i < num_threads; ++i)
 	{
-		threads.emplace_back (attrs, [&io_ctx_a] () {
+		threads.emplace_back (attrs, [this, &io_ctx_a] () {
 			nano::thread_role::set (nano::thread_role::name::io);
+
+			// In a release build, catch and swallow any exceptions,
+			// In debug mode let if fall through
+
+#ifndef NDEBUG
+			run (io_ctx_a);
+#else
 			try
+			{
+				run (io_ctx_a);
+			}
+			catch (std::exception const & ex)
+			{
+				std::cerr << ex.what () << std::endl;
+			}
+			catch (...)
+			{
+			}
+#endif
+		});
+	}
+}
+
+nano::thread_runner::~thread_runner ()
+{
+	join ();
+}
+
+void nano::thread_runner::run (boost::asio::io_context & io_ctx_a)
 {
 #if NANO_ASIO_HANDLER_TRACKING == 0
 	io_ctx_a.run ();
@@ -174,32 +202,6 @@ nano::thread_runner::thread_runner (boost::asio::io_context & io_ctx_a, unsigned
 	}
 #endif
 }
-			catch (std::exception const & ex)
-			{
-				std::cerr << ex.what () << std::endl;
-#ifndef NDEBUG
-				throw;
-#endif
-			}
-			catch (...)
-			{
-#ifndef NDEBUG
-				/*
-				 * In a release build, catch and swallow the
-				 * io_context exception, in debug mode pass it
-				 * on
-				 */
-				throw;
-#endif
-			}
-		});
-	}
-}
-
-nano::thread_runner::~thread_runner ()
-{
-	join ();
-}
 
 void nano::thread_runner::join ()
 {

nano/lib/threading.hpp

@@ -80,14 +80,18 @@ namespace thread_attributes
 class thread_runner final
 {
 public:
-	thread_runner (boost::asio::io_context &, unsigned);
+	thread_runner (boost::asio::io_context &, unsigned num_threads);
 	~thread_runner ();
+
 	/** Tells the IO context to stop processing events.*/
 	void stop_event_processing ();
 	/** Wait for IO threads to complete */
 	void join ();
 	std::vector<boost::thread> threads;
 	boost::asio::executor_work_guard<boost::asio::io_context::executor_type> io_guard;
+
+private:
+	void run (boost::asio::io_context &);
 };
 
 /* Default memory order of normal std::atomic operations is std::memory_order_seq_cst which provides