Major plugin refactor and cleanup.

Switched to POCO library for unified platform/library interface.
Deprecated the external module API. It was creating more problems than solving.
Removed most built-in libraries in favor of system libraries for easier maintenance.
Cleaned and secured code with help from static analyzers.

vendor/POCO/Foundation/include/Poco/PurgeStrategy.h

@@ -0,0 +1,97 @@
+//
+// PurgeStrategy.h
+//
+// Library: Foundation
+// Package: Logging
+// Module:  FileChannel
+//
+// Definition of the PurgeStrategy class.
+//
+// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
+// and Contributors.
+//
+// SPDX-License-Identifier:	BSL-1.0
+//
+
+
+#ifndef Foundation_PurgeStrategy_INCLUDED
+#define Foundation_PurgeStrategy_INCLUDED
+
+
+#include "Poco/Foundation.h"
+#include "Poco/File.h"
+#include "Poco/Timespan.h"
+#include <vector>
+
+
+namespace Poco {
+
+
+class Foundation_API PurgeStrategy
+	/// The PurgeStrategy is used by FileChannel
+	/// to purge archived log files.
+{
+public:
+	PurgeStrategy();
+	virtual ~PurgeStrategy();
+
+	virtual void purge(const std::string& path) = 0;
+		/// Purges archived log files. The path to the
+		/// current "hot" log file is given.
+		/// To find archived log files, look for files
+		/// with a name consisting of the given path 
+		/// plus any suffix (e.g., .1, .20050929081500, .1.gz).
+		/// A list of archived files can be obtained by calling
+		/// the list() method.
+
+protected:
+	void list(const std::string& path, std::vector<File>& files);
+		/// Fills the given vector with a list of archived log
+		/// files. The path of the current "hot" log file is
+		/// given in path.
+		///
+		/// All files with the same name as the one given in path,
+		/// plus some suffix (e.g., .1, .20050929081500, .1.gz) are
+		/// considered archived files.
+
+private:
+	PurgeStrategy(const PurgeStrategy&);
+	PurgeStrategy& operator = (const PurgeStrategy&);
+};
+
+
+class Foundation_API PurgeByAgeStrategy: public PurgeStrategy
+	/// This purge strategy purges all files that have
+	/// exceeded a given age (given in seconds).
+{
+public:
+	PurgeByAgeStrategy(const Timespan& age);
+	~PurgeByAgeStrategy();
+	
+	void purge(const std::string& path);
+	
+private:
+	Timespan _age;
+};
+
+
+class Foundation_API PurgeByCountStrategy: public PurgeStrategy
+	/// This purge strategy ensures that a maximum number
+	/// of archived files is not exceeded. Files are deleted
+	/// based on their age, with oldest files deleted first.
+{
+public:
+	PurgeByCountStrategy(int count);
+	~PurgeByCountStrategy();
+	
+	void purge(const std::string& path);
+	
+private:
+	int _count;
+};
+
+
+} // namespace Poco
+
+
+#endif // Foundation_PurgeStrategy_INCLUDED