BaseDaemon: waitForTerminationRequest() use sigaction instead of sigwait

contrib/libpoco/Util/include/Poco/Util/ServerApplication.h

@@ -163,7 +163,7 @@ public:
 		
 protected:
 	int run();
-	void waitForTerminationRequest();
+	virtual void waitForTerminationRequest();
 #if !defined(_WIN32_WCE)
 	void defineOptions(OptionSet& options);
 #endif

libs/libdaemon/include/daemon/BaseDaemon.h

@@ -52,6 +52,8 @@ namespace Poco { class TaskManager; }
 
 class BaseDaemon : public Poco::Util::ServerApplication
 {
+	friend class SignalListener;
+
 public:
 	BaseDaemon();
     ~BaseDaemon();
@@ -132,6 +134,14 @@ protected:
 	/// Используется при exitOnTaskError()
 	void handleNotification(Poco::TaskFailedNotification *);
 
+	/// thread safe
+	virtual void handleSignal(int signal_id);
+
+	/// реализация обработки сигналов завершения через pipe не требует блокировки сигнала с помощью sigprocmask во всех потоках
+	void waitForTerminationRequest() override;
+	/// thread safe
+	virtual void onInterruptSignals(int signal_id);
+
 	std::unique_ptr<Poco::TaskManager> task_manager;
 
 	/// Создание и автоматическое удаление pid файла.
@@ -156,8 +166,7 @@ protected:
 
 	PID pid;
 
-	/// Получен ли сигнал на завершение? Этот флаг устанавливается в BaseDaemonApplication.
-	bool is_cancelled = false;
+	std::atomic_bool is_cancelled{false};
 
 	/// Флаг устанавливается по сообщению из Task (при аварийном завершении).
 	bool task_failed = false;
@@ -179,4 +188,8 @@ protected:
 	std::unique_ptr<GraphiteWriter> graphite_writer;
 
 	boost::optional<size_t> layer;
+
+	std::mutex signal_handler_mutex;
+	std::condition_variable signal_event;
+	size_t terminate_signals_counter = 0;
 };

libs/libdaemon/src/BaseDaemon.cpp

@@ -131,9 +131,9 @@ static void call_default_signal_handler(int sig)
 using ThreadNumber = decltype(Poco::ThreadNumber::get());
 static const size_t buf_size = sizeof(int) + sizeof(siginfo_t) + sizeof(ucontext_t) + sizeof(ThreadNumber);
 
+using signal_function = void(int, siginfo_t*, void*);
 
-/** Обработчик сигналов HUP / USR1 */
-static void close_logs_signal_handler(int sig, siginfo_t * info, void * context)
+static void writeSignalIDtoSignalPipe(int sig)
 {
 	char buf[buf_size];
 	DB::WriteBufferFromFileDescriptor out(signal_pipe.write_fd, buf_size, buf);
@@ -141,10 +141,21 @@ static void close_logs_signal_handler(int sig, siginfo_t * info, void * context)
 	out.next();
 }
 
+/** Обработчик сигналов HUP / USR1 */
+static void closeLogsSignalHandler(int sig, siginfo_t * info, void * context)
+{
+	writeSignalIDtoSignalPipe(sig);
+}
+
+static void terminateRequestedSignalHandler(int sig, siginfo_t * info, void * context)
+{
+	writeSignalIDtoSignalPipe(sig);
+}
+
 
 /** Обработчик некоторых сигналов. Выводит информацию в лог (если получится).
   */
-static void fault_signal_handler(int sig, siginfo_t * info, void * context)
+static void faultSignalHandler(int sig, siginfo_t * info, void * context)
 {
 	char buf[buf_size];
 	DB::WriteBufferFromFileDescriptor out(signal_pipe.write_fd, buf_size, buf);
@@ -174,7 +185,9 @@ static bool already_printed_stack_trace = false;
 class SignalListener : public Poco::Runnable
 {
 public:
-	SignalListener() : log(&Logger::get("BaseDaemon"))
+	SignalListener(BaseDaemon & daemon_)
+	: log(&Logger::get("BaseDaemon"))
+	, daemon(daemon_)
 	{
 	}
 
@@ -204,6 +217,12 @@ public:
 
 				onTerminate(message, thread_num);
 			}
+			else if (sig == SIGINT ||
+				sig == SIGQUIT ||
+				sig == SIGTERM)
+			{
+				daemon.handleSignal(sig);
+			}
 			else
 			{
 				siginfo_t info;
@@ -221,8 +240,9 @@ public:
 
 private:
 	Logger * log;
+	BaseDaemon & daemon;
 
-
+private:
 	void onTerminate(const std::string & message, ThreadNumber thread_num) const
 	{
 		LOG_ERROR(log, "(from thread " << thread_num << ") " << message);
@@ -739,42 +759,31 @@ void BaseDaemon::initialize(Application& self)
 	std::set_terminate(terminate_handler);
 
 	/// Ставим обработчики сигналов
-	struct sigaction sa;
-	memset(&sa, 0, sizeof(sa));
-	sa.sa_sigaction = fault_signal_handler;
-	sa.sa_flags = SA_SIGINFO;
-
-	{
-		int signals[] = {SIGABRT, SIGSEGV, SIGILL, SIGBUS, SIGSYS, SIGFPE, SIGPIPE, 0};
-
-		if (sigemptyset(&sa.sa_mask))
-			throw Poco::Exception("Cannot set signal handler.");
-
-		for (size_t i = 0; signals[i]; ++i)
-			if (sigaddset(&sa.sa_mask, signals[i]))
-				throw Poco::Exception("Cannot set signal handler.");
-
-		for (size_t i = 0; signals[i]; ++i)
-			if (sigaction(signals[i], &sa, 0))
-				throw Poco::Exception("Cannot set signal handler.");
-	}
-
-	sa.sa_sigaction = close_logs_signal_handler;
+	auto add_signal_handler =
+		[](const std::vector<int> & signals, signal_function handler)
+		{
+			struct sigaction sa;
+			memset(&sa, 0, sizeof(sa));
+			sa.sa_sigaction = handler;
+			sa.sa_flags = SA_SIGINFO;
 
-	{
-		int signals[] = {SIGHUP, SIGUSR1, 0};
+			{
+				if (sigemptyset(&sa.sa_mask))
+					throw Poco::Exception("Cannot set signal handler.");
 
-		if (sigemptyset(&sa.sa_mask))
-			throw Poco::Exception("Cannot set signal handler.");
+				for (auto signal : signals)
+					if (sigaddset(&sa.sa_mask, signal))
+						throw Poco::Exception("Cannot set signal handler.");
 
-		for (size_t i = 0; signals[i]; ++i)
-			if (sigaddset(&sa.sa_mask, signals[i]))
-				throw Poco::Exception("Cannot set signal handler.");
+				for (auto signal : signals)
+					if (sigaction(signal, &sa, 0))
+						throw Poco::Exception("Cannot set signal handler.");
+			}
+		};
 
-		for (size_t i = 0; signals[i]; ++i)
-			if (sigaction(signals[i], &sa, 0))
-				throw Poco::Exception("Cannot set signal handler.");
-	}
+	add_signal_handler({SIGABRT, SIGSEGV, SIGILL, SIGBUS, SIGSYS, SIGFPE, SIGPIPE}, faultSignalHandler);
+	add_signal_handler({SIGHUP, SIGUSR1}, closeLogsSignalHandler);
+	add_signal_handler({SIGINT, SIGQUIT, SIGTERM}, terminateRequestedSignalHandler);
 
 	/// Ставим ErrorHandler для потоков
 	static KillingErrorHandler killing_error_handler;
@@ -783,7 +792,7 @@ void BaseDaemon::initialize(Application& self)
 	/// Выведем ревизию демона
 	logRevision();
 
-	signal_listener.reset(new SignalListener);
+	signal_listener.reset(new SignalListener(*this));
 	signal_listener_thread.start(*signal_listener);
 
 	graphite_writer.reset(new GraphiteWriter("graphite"));
@@ -890,3 +899,35 @@ void BaseDaemon::PID::clear()
 		file.clear();
 	}
 }
+
+void BaseDaemon::handleSignal(int signal_id)
+{
+	if (signal_id == SIGINT ||
+		signal_id == SIGQUIT ||
+		signal_id == SIGTERM)
+	{
+		std::unique_lock<std::mutex> lock(signal_handler_mutex);
+		{
+			++terminate_signals_counter;
+			signal_event.notify_all();
+		}
+
+		onInterruptSignals(signal_id);
+	}
+	else
+		throw DB::Exception(std::string("Unsupported signal: ") + strsignal(signal_id));
+}
+
+void BaseDaemon::onInterruptSignals(int signal_id)
+{
+	is_cancelled = true;
+	LOG_INFO(&logger(), "Received termination signal(" << strsignal(signal_id) << ")");
+}
+
+
+void BaseDaemon::waitForTerminationRequest()
+{
+	std::unique_lock<std::mutex> lock(signal_handler_mutex);
+	signal_event.wait(lock, [this](){ return terminate_signals_counter > 0; });
+}
+