Dynamically create and destroy the timer thread

lib/base/application.cpp

@@ -158,8 +158,6 @@ void Application::InitializeBase(void)
 
 	/* make sure the thread pool gets initialized */
 	GetTP().Start();
-
-	Timer::Initialize();
 }
 
 void Application::UninitializeBase(void)
@@ -317,8 +315,6 @@ void Application::SetArgV(char **argv)
  */
 void Application::RunEventLoop(void)
 {
-	Timer::Initialize();
-
 	double lastLoop = Utility::GetTime();
 
 mainloop:

lib/base/timer.cpp

@@ -71,6 +71,7 @@ static boost::condition_variable l_TimerCV;
 static std::thread l_TimerThread;
 static bool l_StopTimerThread;
 static TimerSet l_Timers;
+static int l_AliveTimers;
 
 /**
  * Constructor for the Timer class.
@@ -87,29 +88,16 @@ Timer::~Timer(void)
 	Stop(true);
 }
 
-/**
- * Initializes the timer sub-system.
- */
-void Timer::Initialize(void)
-{
-	boost::mutex::scoped_lock lock(l_TimerMutex);
-	l_StopTimerThread = false;
-	l_TimerThread = std::thread(&Timer::TimerThreadProc);
-}
-
-/**
- * Disables the timer sub-system.
- */
 void Timer::Uninitialize(void)
 {
-	{
+       {
-		boost::mutex::scoped_lock lock(l_TimerMutex);
+	       boost::mutex::scoped_lock lock(l_TimerMutex);
-		l_StopTimerThread = true;
+	       l_StopTimerThread = true;
-		l_TimerCV.notify_all();
+	       l_TimerCV.notify_all();
-	}
+       }
 
-	if (l_TimerThread.joinable())
+       if (l_TimerThread.joinable())
-		l_TimerThread.join();
+	       l_TimerThread.join();
 }
 
 /**
@@ -158,6 +146,11 @@ void Timer::Start(void)
 	{
 		boost::mutex::scoped_lock lock(l_TimerMutex);
 		m_Started = true;
+
+		if (l_AliveTimers++ == 0) {
+			l_StopTimerThread = false;
+			l_TimerThread = std::thread(&Timer::TimerThreadProc);
+		}
 	}
 
 	InternalReschedule(false);
@@ -173,6 +166,18 @@ void Timer::Stop(bool wait)
 
 	boost::mutex::scoped_lock lock(l_TimerMutex);
 
+	if (m_Started && --l_AliveTimers == 0) {
+		l_StopTimerThread = true;
+		l_TimerCV.notify_all();
+
+		lock.unlock();
+
+		if (l_TimerThread.joinable() && l_TimerThread.get_id() != std::this_thread::get_id())
+			l_TimerThread.join();
+
+		lock.lock();
+	}
+
 	m_Started = false;
 	l_Timers.erase(this);
 

lib/base/timer.hpp

@@ -41,6 +41,8 @@ public:
 	Timer(void);
 	~Timer(void);
 
+	static void Uninitialize(void);
+
 	void SetInterval(double interval);
 	double GetInterval(void) const;
 
@@ -65,10 +67,6 @@ private:
 
 	static void TimerThreadProc(void);
 
-	static void Initialize(void);
-	static void Uninitialize(void);
-
-	friend class Application;
 	friend class TimerHolder;
 };
 

lib/icinga/comment.cpp

@@ -26,6 +26,7 @@
 #include "base/timer.hpp"
 #include <boost/algorithm/string/split.hpp>
 #include <boost/algorithm/string/classification.hpp>
+#include <boost/thread/once.hpp>
 
 using namespace icinga;
 
@@ -37,18 +38,8 @@ static Timer::Ptr l_CommentsExpireTimer;
 boost::signals2::signal<void (const Comment::Ptr&)> Comment::OnCommentAdded;
 boost::signals2::signal<void (const Comment::Ptr&)> Comment::OnCommentRemoved;
 
-INITIALIZE_ONCE(&Comment::StaticInitialize);
-
 REGISTER_TYPE(Comment);
 
-void Comment::StaticInitialize(void)
-{
-	l_CommentsExpireTimer = new Timer();
-	l_CommentsExpireTimer->SetInterval(60);
-	l_CommentsExpireTimer->OnTimerExpired.connect(std::bind(&Comment::CommentsExpireTimerHandler));
-	l_CommentsExpireTimer->Start();
-}
-
 String CommentNameComposer::MakeName(const String& shortName, const Object::Ptr& context) const
 {
 	Comment::Ptr comment = dynamic_pointer_cast<Comment>(context);
@@ -106,6 +97,15 @@ void Comment::Start(bool runtimeCreated)
 {
 	ObjectImpl<Comment>::Start(runtimeCreated);
 
+	static boost::once_flag once = BOOST_ONCE_INIT;
+
+	boost::call_once(once, []() {
+		l_CommentsExpireTimer = new Timer();
+		l_CommentsExpireTimer->SetInterval(60);
+		l_CommentsExpireTimer->OnTimerExpired.connect(std::bind(&Comment::CommentsExpireTimerHandler));
+		l_CommentsExpireTimer->Start();
+	});
+
 	{
 		boost::mutex::scoped_lock lock(l_CommentMutex);
 

lib/icinga/comment.hpp

@@ -56,8 +56,6 @@ public:
 
 	static String GetCommentIDFromLegacyID(int id);
 
-	static void StaticInitialize(void);
-
 protected:
 	virtual void OnAllConfigLoaded(void) override;
 	virtual void Start(bool runtimeCreated) override;

lib/icinga/downtime.cpp

@@ -27,6 +27,7 @@
 #include "base/timer.hpp"
 #include <boost/algorithm/string/split.hpp>
 #include <boost/algorithm/string/classification.hpp>
+#include <boost/thread/once.hpp>
 
 using namespace icinga;
 
@@ -41,23 +42,8 @@ boost::signals2::signal<void (const Downtime::Ptr&)> Downtime::OnDowntimeRemoved
 boost::signals2::signal<void (const Downtime::Ptr&)> Downtime::OnDowntimeStarted;
 boost::signals2::signal<void (const Downtime::Ptr&)> Downtime::OnDowntimeTriggered;
 
-INITIALIZE_ONCE(&Downtime::StaticInitialize);
-
 REGISTER_TYPE(Downtime);
 
-void Downtime::StaticInitialize(void)
-{
-	l_DowntimesStartTimer = new Timer();
-	l_DowntimesStartTimer->SetInterval(5);
-	l_DowntimesStartTimer->OnTimerExpired.connect(std::bind(&Downtime::DowntimesStartTimerHandler));
-	l_DowntimesStartTimer->Start();
-
-	l_DowntimesExpireTimer = new Timer();
-	l_DowntimesExpireTimer->SetInterval(60);
-	l_DowntimesExpireTimer->OnTimerExpired.connect(std::bind(&Downtime::DowntimesExpireTimerHandler));
-	l_DowntimesExpireTimer->Start();
-}
-
 String DowntimeNameComposer::MakeName(const String& shortName, const Object::Ptr& context) const
 {
 	Downtime::Ptr downtime = dynamic_pointer_cast<Downtime>(context);
@@ -115,6 +101,20 @@ void Downtime::Start(bool runtimeCreated)
 {
 	ObjectImpl<Downtime>::Start(runtimeCreated);
 
+	static boost::once_flag once = BOOST_ONCE_INIT;
+
+	boost::call_once(once, []() {
+		l_DowntimesStartTimer = new Timer();
+		l_DowntimesStartTimer->SetInterval(5);
+		l_DowntimesStartTimer->OnTimerExpired.connect(std::bind(&Downtime::DowntimesStartTimerHandler));
+		l_DowntimesStartTimer->Start();
+
+		l_DowntimesExpireTimer = new Timer();
+		l_DowntimesExpireTimer->SetInterval(60);
+		l_DowntimesExpireTimer->OnTimerExpired.connect(std::bind(&Downtime::DowntimesExpireTimerHandler));
+		l_DowntimesExpireTimer->Start();
+	});
+
 	{
 		boost::mutex::scoped_lock lock(l_DowntimeMutex);
 

lib/icinga/downtime.hpp

@@ -65,8 +65,6 @@ public:
 
 	static String GetDowntimeIDFromLegacyID(int id);
 
-	static void StaticInitialize(void);
-
 protected:
 	virtual void OnAllConfigLoaded(void) override;
 	virtual void Start(bool runtimeCreated) override;

lib/icinga/externalcommandprocessor.cpp

@@ -39,6 +39,7 @@
 #include <fstream>
 #include <boost/algorithm/string/classification.hpp>
 #include <boost/algorithm/string/split.hpp>
+#include <boost/thread/once.hpp>
 
 using namespace icinga;
 
@@ -111,6 +112,12 @@ void ExternalCommandProcessor::Execute(double time, const String& command, const
 {
 	ExternalCommandInfo eci;
 
+	static boost::once_flag once = BOOST_ONCE_INIT;
+
+	boost::call_once(once, []() {
+		RegisterCommands();
+	});
+
 	{
 		boost::mutex::scoped_lock lock(GetMutex());
 

lib/icinga/scheduleddowntime.cpp

@@ -24,7 +24,6 @@
 #include "icinga/service.hpp"
 #include "base/timer.hpp"
 #include "base/configtype.hpp"
-#include "base/initialize.hpp"
 #include "base/utility.hpp"
 #include "base/objectlock.hpp"
 #include "base/convert.hpp"
@@ -32,13 +31,12 @@
 #include "base/exception.hpp"
 #include <boost/algorithm/string/split.hpp>
 #include <boost/algorithm/string/classification.hpp>
+#include <boost/thread/once.hpp>
 
 using namespace icinga;
 
 REGISTER_TYPE(ScheduledDowntime);
 
-INITIALIZE_ONCE(&ScheduledDowntime::StaticInitialize);
-
 static Timer::Ptr l_Timer;
 
 String ScheduledDowntimeNameComposer::MakeName(const String& shortName, const Object::Ptr& context) const
@@ -79,14 +77,6 @@ Dictionary::Ptr ScheduledDowntimeNameComposer::ParseName(const String& name) con
 	return result;
 }
 
-void ScheduledDowntime::StaticInitialize(void)
-{
-	l_Timer = new Timer();
-	l_Timer->SetInterval(60);
-	l_Timer->OnTimerExpired.connect(std::bind(&ScheduledDowntime::TimerProc));
-	l_Timer->Start();
-}
-
 void ScheduledDowntime::OnAllConfigLoaded(void)
 {
 	ObjectImpl<ScheduledDowntime>::OnAllConfigLoaded();
@@ -99,6 +89,15 @@ void ScheduledDowntime::Start(bool runtimeCreated)
 {
 	ObjectImpl<ScheduledDowntime>::Start(runtimeCreated);
 
+	static boost::once_flag once = BOOST_ONCE_INIT;
+
+	boost::call_once(once, []() {
+		l_Timer = new Timer();
+		l_Timer->SetInterval(60);
+		l_Timer->OnTimerExpired.connect(std::bind(&ScheduledDowntime::TimerProc));
+		l_Timer->Start();
+	});
+
 	Utility::QueueAsyncCallback(std::bind(&ScheduledDowntime::CreateNextDowntime, this));
 }
 

lib/icinga/scheduleddowntime.hpp

@@ -44,8 +44,6 @@ public:
 	DECLARE_OBJECT(ScheduledDowntime);
 	DECLARE_OBJECTNAME(ScheduledDowntime);
 
-	static void StaticInitialize(void);
-
 	Checkable::Ptr GetCheckable(void) const;
 
 	static void EvaluateApplyRules(const intrusive_ptr<Host>& host);

lib/icinga/timeperiod.cpp

@@ -26,6 +26,7 @@
 #include "base/logger.hpp"
 #include "base/timer.hpp"
 #include "base/utility.hpp"
+#include <boost/thread/once.hpp>
 
 using namespace icinga;
 
@@ -33,20 +34,19 @@ REGISTER_TYPE(TimePeriod);
 
 static Timer::Ptr l_UpdateTimer;
 
-INITIALIZE_ONCE(&TimePeriod::StaticInitialize);
-
-void TimePeriod::StaticInitialize(void)
-{
-	l_UpdateTimer = new Timer();
-	l_UpdateTimer->SetInterval(300);
-	l_UpdateTimer->OnTimerExpired.connect(std::bind(&TimePeriod::UpdateTimerHandler));
-	l_UpdateTimer->Start();
-}
-
 void TimePeriod::Start(bool runtimeCreated)
 {
 	ObjectImpl<TimePeriod>::Start(runtimeCreated);
 
+	static boost::once_flag once = BOOST_ONCE_INIT;
+
+	boost::call_once(once, []() {
+		l_UpdateTimer = new Timer();
+		l_UpdateTimer->SetInterval(300);
+		l_UpdateTimer->OnTimerExpired.connect(std::bind(&TimePeriod::UpdateTimerHandler));
+		l_UpdateTimer->Start();
+	});
+
 	/* Pre-fill the time period for the next 24 hours. */
 	double now = Utility::GetTime();
 	UpdateRegion(now, now + 24 * 3600, true);

lib/icinga/timeperiod.hpp

@@ -37,8 +37,6 @@ public:
 	DECLARE_OBJECT(TimePeriod);
 	DECLARE_OBJECTNAME(TimePeriod);
 
-	static void StaticInitialize(void);
-
 	virtual void Start(bool runtimeCreated) override;
 
 	void UpdateRegion(double begin, double end, bool clearExisting);

lib/remote/consolehandler.cpp

@@ -29,6 +29,7 @@
 #include "base/timer.hpp"
 #include "base/initialize.hpp"
 #include <boost/algorithm/string.hpp>
+#include <boost/thread/once.hpp>
 #include <set>
 
 using namespace icinga;
@@ -57,12 +58,17 @@ static void ScriptFrameCleanupHandler(void)
 		l_ApiScriptFrames.erase(key);
 }
 
-INITIALIZE_ONCE([]() {
+static void EnsureFrameCleanupTimer(void)
-	l_FrameCleanupTimer = new Timer();
+{
-	l_FrameCleanupTimer->OnTimerExpired.connect(std::bind(ScriptFrameCleanupHandler));
+	static boost::once_flag once = BOOST_ONCE_INIT;
-	l_FrameCleanupTimer->SetInterval(30);
+
-	l_FrameCleanupTimer->Start();
+	boost::call_once(once, []() {
-});
+		l_FrameCleanupTimer = new Timer();
+		l_FrameCleanupTimer->OnTimerExpired.connect(std::bind(ScriptFrameCleanupHandler));
+		l_FrameCleanupTimer->SetInterval(30);
+		l_FrameCleanupTimer->Start();
+	});
+}
 
 bool ConsoleHandler::HandleRequest(const ApiUser::Ptr& user, HttpRequest& request, HttpResponse& response, const Dictionary::Ptr& params)
 {
@@ -102,6 +108,8 @@ bool ConsoleHandler::ExecuteScriptHelper(HttpRequest& request, HttpResponse& res
 	Log(LogNotice, "Console")
 	    << "Executing expression: " << command;
 
+	EnsureFrameCleanupTimer();
+
 	ApiScriptFrame& lsf = l_ApiScriptFrames[session];
 	lsf.Seen = Utility::GetTime();
 
@@ -175,6 +183,8 @@ bool ConsoleHandler::AutocompleteScriptHelper(HttpRequest& request, HttpResponse
 	Log(LogInformation, "Console")
 	    << "Auto-completing expression: " << command;
 
+	EnsureFrameCleanupTimer();
+
 	ApiScriptFrame& lsf = l_ApiScriptFrames[session];
 	lsf.Seen = Utility::GetTime();
 

lib/remote/jsonrpcconnection-heartbeat.cpp

@@ -29,15 +29,6 @@ using namespace icinga;
 
 REGISTER_APIFUNCTION(Heartbeat, event, &JsonRpcConnection::HeartbeatAPIHandler);
 
-static Timer::Ptr l_HeartbeatTimer;
-
-INITIALIZE_ONCE([]() {
-	l_HeartbeatTimer = new Timer();
-	l_HeartbeatTimer->OnTimerExpired.connect(std::bind(&JsonRpcConnection::HeartbeatTimerHandler));
-	l_HeartbeatTimer->SetInterval(10);
-	l_HeartbeatTimer->Start();
-});
-
 void JsonRpcConnection::HeartbeatTimerHandler(void)
 {
 	for (const Endpoint::Ptr& endpoint : ConfigType::GetObjectsByType<Endpoint>()) {

lib/remote/jsonrpcconnection.cpp

@@ -39,6 +39,7 @@ static Timer::Ptr l_JsonRpcConnectionTimeoutTimer;
 static WorkQueue *l_JsonRpcConnectionWorkQueues;
 static size_t l_JsonRpcConnectionWorkQueueCount;
 static int l_JsonRpcConnectionNextID;
+static Timer::Ptr l_HeartbeatTimer;
 
 JsonRpcConnection::JsonRpcConnection(const String& identity, bool authenticated,
     const TlsStream::Ptr& stream, ConnectionRole role)
@@ -65,6 +66,11 @@ void JsonRpcConnection::StaticInitialize(void)
 	for (size_t i = 0; i < l_JsonRpcConnectionWorkQueueCount; i++) {
 		l_JsonRpcConnectionWorkQueues[i].SetName("JsonRpcConnection, #" + Convert::ToString(i));
 	}
+
+	l_HeartbeatTimer = new Timer();
+	l_HeartbeatTimer->OnTimerExpired.connect(std::bind(&JsonRpcConnection::HeartbeatTimerHandler));
+	l_HeartbeatTimer->SetInterval(10);
+	l_HeartbeatTimer->Start();
 }
 
 void JsonRpcConnection::Start(void)