another scheme, without ABI-15 breaks

src/examples/cpp/custom-appender.cpp

@@ -38,8 +38,6 @@ class NullWriterAppender : public log4cxx::AppenderSkeleton {
 		return false;
 	}
 
-	void flushBuffers() override{}
-
 	void append(const spi::LoggingEventPtr& event, log4cxx::helpers::Pool& p) override {
 		// This gets called whenever there is a valid event for our appender.
 	}

src/main/cpp/CMakeLists.txt

@@ -207,6 +207,12 @@ target_sources(log4cxx
   ${extra_classes}
 )
 
+if(LOG4CXX_EVENTS_AT_EXIT)
+  target_sources(log4cxx
+    PRIVATE atexitregistry.cpp
+  )
+endif(WIN32)
+
 if(WIN32)
   target_sources(log4cxx
     PRIVATE visualstudio.natvis

src/main/cpp/appenderattachableimpl.cpp

@@ -183,10 +183,4 @@ void AppenderAttachableImpl::removeAppender(const LogString& name)
 	}
 }
 
-void AppenderAttachableImpl::flushBuffers()
-{
-	std::lock_guard<std::recursive_mutex> lock( m_priv->m_mutex );
-	for(const AppenderPtr& appender : m_priv->appenderList)
-		appender->flushBuffers();
-}
 

src/main/cpp/asyncappender.cpp

@@ -30,6 +30,10 @@
 #include <log4cxx/helpers/threadutility.h>
 #include <log4cxx/private/appenderskeleton_priv.h>
 
+#if LOG4CXX_EVENTS_AT_EXIT
+#include <log4cxx/private/atexitregistry.h>
+#endif
+
 using namespace LOG4CXX_NS;
 using namespace LOG4CXX_NS::helpers;
 using namespace LOG4CXX_NS::spi;
@@ -103,7 +107,22 @@ struct AsyncAppender::AsyncAppenderPriv : public AppenderSkeleton::AppenderSkele
 		appenders(std::make_shared<AppenderAttachableImpl>(pool)),
 		dispatcher(),
 		locationInfo(false),
-		blocking(true) {}
+		blocking(true)
+#if LOG4CXX_EVENTS_AT_EXIT
+		, atExitRegistryRaii([this]{atExitActivated();})
+#endif
+	{
+	}
+
+#if LOG4CXX_EVENTS_AT_EXIT
+	void atExitActivated()
+	{
+		std::unique_lock<std::mutex> lock(bufferMutex);
+		bufferNotFull.wait(lock, [this]() -> bool
+			{ return buffer.empty() || closed; }
+		);
+	}
+#endif
 
 	/**
 	 * Event buffer.
@@ -157,6 +176,10 @@ struct AsyncAppender::AsyncAppenderPriv : public AppenderSkeleton::AppenderSkele
 	 * Does appender block when buffer is full.
 	*/
 	bool blocking;
+
+#if LOG4CXX_EVENTS_AT_EXIT
+	helpers::AtExitRegistry::Raii atExitRegistryRaii;
+#endif
 };
 
 
@@ -341,14 +364,6 @@ bool AsyncAppender::requiresLayout() const
 	return false;
 }
 
-void AsyncAppender::flushBuffers()
-{
-	std::unique_lock<std::mutex> lock(priv->bufferMutex);
-	priv->bufferNotFull.wait(lock, [this]() -> bool
-		{ return priv->buffer.empty() || priv->closed; }
-	);
-}
-
 void AsyncAppender::removeAllAppenders()
 {
 	priv->appenders->removeAllAppenders();

src/main/cpp/hierarchy.cpp

@@ -474,16 +474,6 @@ bool Hierarchy::isConfigured()
 	return m_priv->configured;
 }
 
-void Hierarchy::flushBuffers()
-{
-	std::unique_lock<std::mutex> lock(m_priv->mutex);
-	for (auto& item : m_priv->loggers)
-		if (auto& pLogger = item.second)
-			pLogger->flushBuffers();
-	if (m_priv->root)
-		m_priv->root->flushBuffers();
-}
-
 HierarchyPtr Hierarchy::create()
 {
 	HierarchyPtr ret(new Hierarchy);

src/main/cpp/logger.cpp

@@ -515,11 +515,6 @@ void Logger::removeAppender(const LogString& name1)
 	m_priv->aai.removeAppender(name1);
 }
 
-void Logger::flushBuffers()
-{
-	m_priv->aai.flushBuffers();
-}
-
 void Logger::removeHierarchy()
 {
 	m_priv->repositoryRaw = 0;

src/main/cpp/logmanager.cpp

@@ -200,25 +200,6 @@ LoggerList LogManager::getCurrentLoggers()
 	return getLoggerRepository()->getCurrentLoggers();
 }
 
-void LogManager::flushBuffers()
-{
-	getLoggerRepository()->flushBuffers();
-}
-
-#if LOG4CXX_EVENTS_AT_EXIT
-// initiate buffers flush at static deinitialization phase
-namespace
-{
-	struct FlushBuffersAtExit
-	{
-		~FlushBuffersAtExit()
-		{
-			LogManager::flushBuffers();
-		}
-	} s_flushBuffersAtExit;
-}
-#endif
-
 void LogManager::shutdown()
 {
 	APRInitializer::unregisterAll();

src/main/cpp/smtpappender.cpp

@@ -447,11 +447,6 @@ bool SMTPAppender::requiresLayout() const
 	return true;
 }
 
-void SMTPAppender::flushBuffers()
-{
-	sendBuffer(_priv->pool);
-}
-
 LogString SMTPAppender::getFrom() const
 {
 	return _priv->from;

src/main/cpp/writerappender.cpp

@@ -304,12 +304,6 @@ bool WriterAppender::requiresLayout() const
 	return true;
 }
 
-void WriterAppender::flushBuffers()
-{
-	if (_priv->layout != NULL)
-		_priv->writer->flush(_priv->pool);
-}
-
 void WriterAppender::setOption(const LogString& option, const LogString& value)
 {
 	if (StringHelper::equalsIgnoreCase(option, LOG4CXX_STR("ENCODING"), LOG4CXX_STR("encoding")))

src/main/include/log4cxx/appender.h

@@ -127,11 +127,6 @@ class LOG4CXX_EXPORT Appender :
 		 the appender should return <code>true</code>.
 		*/
 		virtual bool requiresLayout() const = 0;
-
-		/**
-		 Flush all buffered data if present.
-		*/
-		virtual void flushBuffers() = 0;
 };
 
 LOG4CXX_PTR_DEF(Appender);

src/main/include/log4cxx/asyncappender.h

@@ -121,11 +121,6 @@ class LOG4CXX_EXPORT AsyncAppender :
 
 		bool requiresLayout() const override;
 
-		/**
-		* Flush all buffered data if present.
-		*/
-		void flushBuffers() override;
-
 		/**
 		 * Removes and closes all attached appenders.
 		*/

src/main/include/log4cxx/db/dbappender.h

@@ -158,11 +158,6 @@ class LOG4CXX_EXPORT DBAppender : public AppenderSkeleton
                         return false;
                 }
 
-                /**
-                * There are no bufferred data here, no action required
-                * */
-                void flushBuffers() override {}
-
                 /**
                 * Set pre-formated statement eg: insert into LogTable (msg) values (?)
                 */

src/main/include/log4cxx/db/odbcappender.h

@@ -233,13 +233,6 @@ class LOG4CXX_EXPORT ODBCAppender : public AppenderSkeleton
 		* */
 		bool requiresLayout() const override;
 
-		/**
-		* There are no bufferred data here, no action required
-		* */
-		void flushBuffers() override
-		{
-		}
-
 		/**
 		* Set pre-formated statement eg: insert into LogTable (msg) values ("%m")
 		*/

src/main/include/log4cxx/helpers/appenderattachableimpl.h

@@ -101,11 +101,6 @@ class LOG4CXX_EXPORT AppenderAttachableImpl :
 		 */
 		void removeAppender(const LogString& name) override;
 
-		/**
-		* Flush all buffered data if present.
-		*/
-		void flushBuffers() override;
-
 	private:
 		LOG4CXX_DECLARE_PRIVATE_MEMBER_PTR(priv_data, m_priv)
 

src/main/include/log4cxx/hierarchy.h

@@ -219,11 +219,6 @@ class LOG4CXX_EXPORT Hierarchy : public spi::LoggerRepository
 		virtual bool isConfigured() override;
 		virtual void setConfigured(bool configured) override;
 
-		/**
-		Flush all buffered data in all appenders if present.
-		*/
-		void flushBuffers() override;
-
 		/**
 		Refresh the threshold in children of parent
 		*/

src/main/include/log4cxx/logger.h

@@ -1652,11 +1652,6 @@ class LOG4CXX_EXPORT Logger :
 		 */
 		void removeAppender(const LogString& name) override;
 
-		/**
-		Flush all buffered data in all downstream appenders if present.
-		*/
-		void flushBuffers() override;
-
 		/**
 		 Set the additivity flag for this logger.
 		  */

src/main/include/log4cxx/logmanager.h

@@ -211,11 +211,6 @@ class LOG4CXX_EXPORT LogManager
 
 		static LoggerList getCurrentLoggers();
 
-		/**
-		 Flush all buffered data in all loggers/appenders if present.
-		*/
-		static void flushBuffers();
-
 		/**
 		Safely close and remove all appenders in all loggers including
 		the root logger.

src/main/include/log4cxx/net/smtpappender.h

@@ -173,11 +173,6 @@ class LOG4CXX_EXPORT SMTPAppender : public AppenderSkeleton
 		*/
 		bool requiresLayout() const override;
 
-		/**
-		Flush all buffered data if present.
-		*/
-		void flushBuffers() override;
-
 		/**
 		Send the contents of the cyclic buffer as an e-mail message.
 		*/

src/main/include/log4cxx/net/socketappenderskeleton.h

@@ -71,13 +71,6 @@ class LOG4CXX_EXPORT SocketAppenderSkeleton : public AppenderSkeleton
 			return false;
 		}
 
-		/**
-		* There are no bufferred data here, no action required
-		* */
-		void flushBuffers() override
-		{
-		}
-
 		/**
 		* The <b>RemoteHost</b> option takes a string value which should be
 		* the host name of the server where a

src/main/include/log4cxx/net/syslogappender.h

@@ -108,13 +108,6 @@ class LOG4CXX_EXPORT SyslogAppender : public AppenderSkeleton
 			return true;
 		}
 
-		/**
-		* There are no bufferred data here, no action required
-		* */
-		void flushBuffers() override
-		{
-		}
-
 		/**
 		The <b>SyslogHost</b> option is the name of the the syslog host
 		where log output should go.

src/main/include/log4cxx/net/telnetappender.h

@@ -87,13 +87,6 @@ class LOG4CXX_EXPORT TelnetAppender : public AppenderSkeleton
 			return true;
 		}
 
-		/**
-		* There are no bufferred data here, no action required
-		* */
-		void flushBuffers() override
-		{
-		}
-
 		/**
 		The current encoding value.
 

src/main/include/log4cxx/nt/nteventlogappender.h

@@ -77,11 +77,6 @@ class LOG4CXX_EXPORT NTEventLogAppender : public AppenderSkeleton
 			return true;
 		}
 
-		/**
-		* There are no bufferred data here, no action required
-		* */
-		void flushBuffers() override {}
-
 		void setSource(const LogString& source);
 
 		const LogString& getSource() const;

src/main/include/log4cxx/nt/outputdebugstringappender.h

@@ -43,8 +43,6 @@ class LOG4CXX_EXPORT OutputDebugStringAppender : public AppenderSkeleton
 		void close() override {}
 
 		void append(const spi::LoggingEventPtr& event, helpers::Pool& p) override;
-
-		void flushBuffers() override {}
 };
 }
 }