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/SyslogChannel.h

@@ -0,0 +1,111 @@
+//
+// SyslogChannel.h
+//
+// Library: Foundation
+// Package: Logging
+// Module:  SyslogChannel
+//
+// Definition of the SyslogChannel class specific to UNIX.
+//
+// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
+// and Contributors.
+//
+// SPDX-License-Identifier:	BSL-1.0
+//
+
+
+#ifndef Foundation_SyslogChannel_INCLUDED
+#define Foundation_SyslogChannel_INCLUDED
+
+
+#include "Poco/Foundation.h"
+#include "Poco/Channel.h"
+
+
+namespace Poco {
+
+
+class Foundation_API SyslogChannel: public Channel
+	/// This Unix-only channel works with the Unix syslog service.
+{
+public:
+	using Ptr = AutoPtr<SyslogChannel>;
+
+	enum Option
+	{
+		SYSLOG_PID    = 0x01, /// log the pid with each message
+		SYSLOG_CONS   = 0x02, /// log on the console if errors in sending
+		SYSLOG_NDELAY = 0x08, /// don't delay open
+		SYSLOG_PERROR = 0x20  /// log to stderr as well (not supported on all platforms)
+	};
+	
+	enum Facility
+	{
+		SYSLOG_KERN     = ( 0<<3), /// kernel messages
+		SYSLOG_USER     = ( 1<<3), /// random user-level messages
+		SYSLOG_MAIL     = ( 2<<3), /// mail system
+		SYSLOG_DAEMON   = ( 3<<3), /// system daemons
+		SYSLOG_AUTH     = ( 4<<3), /// security/authorization messages
+		SYSLOG_SYSLOG   = ( 5<<3), /// messages generated internally by syslogd
+		SYSLOG_LPR      = ( 6<<3), /// line printer subsystem
+		SYSLOG_NEWS     = ( 7<<3), /// network news subsystem
+		SYSLOG_UUCP     = ( 8<<3), /// UUCP subsystem
+		SYSLOG_CRON     = ( 9<<3), /// clock daemon
+		SYSLOG_AUTHPRIV = (10<<3), /// security/authorization messages (private)
+		SYSLOG_FTP      = (11<<3), /// ftp daemon
+		SYSLOG_LOCAL0   = (16<<3), /// reserved for local use
+		SYSLOG_LOCAL1   = (17<<3), /// reserved for local use
+		SYSLOG_LOCAL2   = (18<<3), /// reserved for local use
+		SYSLOG_LOCAL3   = (19<<3), /// reserved for local use
+		SYSLOG_LOCAL4   = (20<<3), /// reserved for local use
+		SYSLOG_LOCAL5   = (21<<3), /// reserved for local use
+		SYSLOG_LOCAL6   = (22<<3), /// reserved for local use
+		SYSLOG_LOCAL7   = (23<<3)  /// reserved for local use
+	};
+	
+	SyslogChannel();
+		/// Creates a SyslogChannel.
+		
+	SyslogChannel(const std::string& name, int options = SYSLOG_CONS, int facility = SYSLOG_USER);
+		/// Creates a SyslogChannel with the given name, options and facility.
+	
+	void open();
+		/// Opens the SyslogChannel.
+		
+	void close();
+		/// Closes the SyslogChannel.
+		
+	void log(const Message& msg);
+		/// Sens the message's text to the syslog service.
+		
+	void setProperty(const std::string& name, const std::string& value);
+		/// Sets the property with the given value.
+		///
+		/// The following properties are supported:
+		///     * name:     The name used to identify the source of log messages.
+		///     * facility: The facility added to each log message. See the Facility enumeration for a list of supported values.
+		///     * options:  The logging options. See the Option enumeration for a list of supported values.
+		
+	std::string getProperty(const std::string& name) const;
+		/// Returns the value of the property with the given name.
+
+	static const std::string PROP_NAME;
+	static const std::string PROP_FACILITY;
+	static const std::string PROP_OPTIONS;
+
+protected:
+	~SyslogChannel();
+	static int getPrio(const Message& msg);
+
+private:
+	std::string _name;
+	int  _options;
+	int  _facility;
+	bool _open;
+};
+
+
+} // namespace Poco
+
+
+#endif // Foundation_SyslogChannel_INCLUDED