/*
 * Copyright 2003,2004 The Apache Software Foundation.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
 
#ifndef _LOG4CXX_HELPERS_FILEWATCHDOG_H
#define _LOG4CXX_HELPERS_FILEWATCHDOG_H

#include <log4cxx/helpers/tchar.h>
#include <log4cxx/helpers/thread.h>
#include <time.h>

namespace log4cxx
{
	namespace helpers
	{
		
		/**
		Check every now and then that a certain file has not changed. If it
		has, then call the #doOnChange method.
		*/
		class LOG4CXX_EXPORT FileWatchdog : public Thread
		{
		public:
			/**
			The default delay between every file modification check, set to 60
			seconds.  */
			static long DEFAULT_DELAY /*= 60000*/; 

		protected:
			/**
			The name of the file to observe  for changes.
			*/
			String filename;
			
			/**
			The delay to observe between every check. 
			By default set DEFAULT_DELAY.*/
			long delay; 
			time_t lastModif; 
			bool warnedAlready;
			bool interrupted;
			
		protected:
			FileWatchdog(const String& filename);
			virtual void doOnChange() = 0;
			void checkAndConfigure();

		public:
			/**
			Set the delay to observe between each check of the file changes.
			*/
			void setDelay(long delay)
				{ this->delay = delay; }
				
			void run();
			void start();
		};
	}  // namespace helpers
}; // namespace log4cxx


#endif // _LOG4CXX_HELPERS_FILEWATCHDOG_H