Converting log writers and input readers to plugins.

src/logging/Component.h

@@ -0,0 +1,59 @@
+// See the file "COPYING" in the main distribution directory for copyright.
+
+#ifndef LOGGING_COMPONENT_H
+#define LOGGING_COMPONENT_H
+
+#include "Tag.h"
+#include "plugin/Component.h"
+#include "plugin/TaggedComponent.h"
+
+namespace logging {
+
+class WriterFrontend;
+class WriterBackend;
+
+/**
+ * Component description for plugins providing log writers.
+ */
+class Component : public plugin::Component,
+		  public plugin::TaggedComponent<logging::Tag> {
+public:
+	typedef WriterBackend* (*factory_callback)(WriterFrontend* frontend);
+
+	/**
+	 * Constructor.
+	 *
+	 * @param name The name of the provided writer. This name is used
+	 * across the system to identify the writer.
+	 *
+	 * @param factory A factory function to instantiate instances of the
+	 * writers's class, which must be derived directly or indirectly from
+	 * logging::WriterBackend. This is typically a static \c Instatiate()
+	 * method inside the class that just allocates and returns a new
+	 * instance.
+	 */
+	Component(const std::string& name, factory_callback factory);
+
+	/**
+	 * Destructor.
+	 */
+	~Component();
+
+	/**
+	 * Returns the writer's factory function.
+	 */
+	factory_callback Factory() const	{ return factory; }
+
+protected:
+	/**
+	  * Overriden from plugin::Component.
+	  */
+	virtual void DoDescribe(ODesc* d) const;
+
+private:
+	factory_callback factory;
+};
+
+}
+
+#endif