From b879b2bf70c80d40e2ea64ce69b3ae960571a054 Mon Sep 17 00:00:00 2001
From: Stephen Webb <stephen.webb@ieee.org>
Date: Thu, 16 May 2024 12:22:37 +1000
Subject: [PATCH] Warn about each instance of a mis-configured appender (#385)

---
 src/main/cpp/appenderskeleton.cpp             | 31 ++++++++++++++
 src/main/cpp/writerappender.cpp               | 42 ++++---------------
 .../log4cxx/private/appenderskeleton_priv.h   |  6 +++
 .../log4cxx/private/writerappender_priv.h     |  3 ++
 4 files changed, 49 insertions(+), 33 deletions(-)

diff --git a/src/main/cpp/appenderskeleton.cpp b/src/main/cpp/appenderskeleton.cpp
index 878a89dc2..3a5e74958 100644
--- a/src/main/cpp/appenderskeleton.cpp
+++ b/src/main/cpp/appenderskeleton.cpp
@@ -131,6 +131,37 @@ void AppenderSkeleton::doAppendImpl(const spi::LoggingEventPtr& event, Pool& poo
 	append(event, pool1);
 }
 
+bool AppenderSkeleton::AppenderSkeletonPrivate::checkNotClosed()
+{
+	if (this->closed)
+	{
+		if (!this->warnedClosed)
+		{
+			LogLog::warn(LOG4CXX_STR("Not allowed to write to a closed appender."));
+			this->warnedClosed = true;
+		}
+		return false;
+	}
+	return true;
+}
+
+bool AppenderSkeleton::AppenderSkeletonPrivate::checkLayout()
+{
+	if (!this->layout)
+	{
+		if (!this->warnedNoLayout)
+		{
+			this->errorHandler->error
+				( LogString(LOG4CXX_STR("No layout set for the appender named ["))
+				+ this->name + LOG4CXX_STR("].")
+				);
+			this->warnedNoLayout = true;
+		}
+		return false;
+	}
+	return true;
+}
+
 void AppenderSkeleton::setErrorHandler(const spi::ErrorHandlerPtr errorHandler1)
 {
 	std::lock_guard<std::recursive_mutex> lock(m_priv->mutex);
diff --git a/src/main/cpp/writerappender.cpp b/src/main/cpp/writerappender.cpp
index 5751f2556..b1c5a6899 100644
--- a/src/main/cpp/writerappender.cpp
+++ b/src/main/cpp/writerappender.cpp
@@ -107,46 +107,22 @@ void WriterAppender::append(const spi::LoggingEventPtr& event, Pool& pool1)
    value <code>false</code> is returned. */
 bool WriterAppender::checkEntryConditions() const
 {
-	static bool warnedClosed = false;
-	static bool warnedNoWriter = false;
-	static bool warnedNoLayout = false;
-
-	if (_priv->closed)
-	{
-		if (!warnedClosed)
-		{
-			LogLog::warn(LOG4CXX_STR("Not allowed to write to a closed appender."));
-			warnedClosed = true;
-		}
-
-		return false;
-	}
+	return _priv->checkWriter() && _priv->checkLayout() && _priv->checkNotClosed();
+}
 
-	if (_priv->writer == 0)
+bool WriterAppender::WriterAppenderPriv::checkWriter()
+{
+	if (this->writer == 0)
 	{
-		if (!warnedNoWriter)
+		if (!this->warnedNoWriter)
 		{
-			_priv->errorHandler->error(
+			this->errorHandler->error(
 				LogString(LOG4CXX_STR("No output stream or file set for the appender named [")) +
-				_priv->name + LOG4CXX_STR("]."));
-			warnedNoWriter = true;
-		}
-
-		return false;
-	}
-
-	if (_priv->layout == 0)
-	{
-		if (!warnedNoLayout)
-		{
-			_priv->errorHandler->error(
-				LogString(LOG4CXX_STR("No layout set for the appender named [")) +
-				_priv->name + LOG4CXX_STR("]."));
-			warnedNoLayout = true;
+				this->name + LOG4CXX_STR("]."));
+			this->warnedNoWriter = true;
 		}
 		return false;
 	}
-
 	return true;
 }
 
diff --git a/src/main/include/log4cxx/private/appenderskeleton_priv.h b/src/main/include/log4cxx/private/appenderskeleton_priv.h
index b9660cf3d..cba7bec45 100644
--- a/src/main/include/log4cxx/private/appenderskeleton_priv.h
+++ b/src/main/include/log4cxx/private/appenderskeleton_priv.h
@@ -70,6 +70,12 @@ struct AppenderSkeleton::AppenderSkeletonPrivate
 
 	LOG4CXX_NS::helpers::Pool pool;
 	mutable std::recursive_mutex mutex;
+
+	bool warnedClosed = false;
+	bool checkNotClosed();
+
+	bool warnedNoLayout = false;
+	bool checkLayout();
 };
 
 }
diff --git a/src/main/include/log4cxx/private/writerappender_priv.h b/src/main/include/log4cxx/private/writerappender_priv.h
index 752c1c3c5..30f52eea4 100644
--- a/src/main/include/log4cxx/private/writerappender_priv.h
+++ b/src/main/include/log4cxx/private/writerappender_priv.h
@@ -101,6 +101,9 @@ struct WriterAppender::WriterAppenderPriv : public AppenderSkeleton::AppenderSke
 #if LOG4CXX_EVENTS_AT_EXIT
 	helpers::AtExitRegistry::Raii atExitRegistryRaii;
 #endif
+
+	bool warnedNoWriter = false;
+	bool checkWriter();
 };
 
 }