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 * Licensed to the Apache Software Foundation (ASF) under one
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 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
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/* Information:
 * This class implements a mechanism to lock a users installation directory,
 * which is necessesary because instances of staroffice could be running on 
 * different hosts while using the same directory thus causing data 
 * inconsistency.
 * When an existing lock is detected, the user will be asked whether he wants
 * to continue anyway, thus removing the lock and replacing it with a new one
 *
 * ideas:
 * - store information about user and host and time in the lockfile and display 
 * these when asking whether to remove the lockfile.
 * - periodically check the lockfile and warn the user when it gets replaced
 *
 */

#include "sal/types.h"
#include "rtl/ustring.hxx"

class ByteString;

namespace desktop {

	class Lockfile;
	bool Lockfile_execWarning( Lockfile * that );

	class Lockfile
	{
	public:

		// contructs a new lockfile onject
		Lockfile( bool bIPCserver = true );

        // separating GUI code:
        typedef bool (* fpExecWarning)( Lockfile * that );
        
		// checks the lockfile, asks user when lockfile is 
		// found (iff gui) and returns false when we may not continue
		sal_Bool check( fpExecWarning execWarning );

		// removes the lockfile. should only be called in exceptional situations
		void clean(void);

		// removes the lockfile
		~Lockfile(void);

	private:
		// data in lockfile
		static const ByteString Group();
		static const ByteString Userkey();
		static const ByteString Hostkey();
		static const ByteString Stampkey();
		static const ByteString Timekey();
		static const ByteString IPCkey();
		// lockfilename
		static const rtl::OUString Suffix();
		bool m_bIPCserver;
		// full qualified name (file://-url) of the lockfile
		rtl::OUString m_aLockname;
		// flag whether the d'tor should delete the lock
		sal_Bool m_bRemove;
		sal_Bool m_bIsLocked;
		// ID 
		rtl::OUString m_aId;
		rtl::OUString m_aDate;
		// access to data in file
		void syncToFile(void) const;
		sal_Bool isStale(void) const;
        friend bool Lockfile_execWarning( Lockfile * that );

	};

}