core/sql/refresh/RuLockEquivSetTaskExecutor.h

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#ifndef _RU_LOCK_EQUIV_TASK_EXECUTOR_H_
#define _RU_LOCK_EQUIV_TASK_EXECUTOR_H_

/* -*-C++-*-
******************************************************************************
*
* File:         RuLockEquivSetTaskExecutor.h
* Description:  Definition of class CRULockEquivSetTaskExecutor.
*
* Created:      12/06/2000
* Language:     C++
*
*
******************************************************************************
*/

#include "refresh.h"

#include "RuTaskExecutor.h"

class CRUTbl;
class CRULockEquivSetTask;
class CUOFsIpcMessageTranslator;

//--------------------------------------------------------------------------//
//	CRULockEquivSetTaskExecutor
//	
//	The executor execute a table synchronization by locking all the 
//  tables or the tables' logs that are members of the this 
//  lock equivalent set.
//	
//	If only the table log is needed , the lock on the log will remain until
//  the epoch incremenet will occure and then it will be released.
//  If only the table is needed (An epoch increment will not occur) 
//  the executor will place a lock only on the table which will be released 
//  when the last customer of this lock will be refreshed
//
//  The order of placing the lock on the tables in the set is determined by
//  the following rule - The tables that have no lock on refresh attribute 
//  will be locked last. This rule is implemented by the order of the tables
//  in the list
//--------------------------------------------------------------------------//

class REFRESH_LIB_CLASS CRULockEquivSetTaskExecutor : public CRUTaskExecutor
{
private:
	typedef CRUTaskExecutor inherited;

public:
	CRULockEquivSetTaskExecutor(CRUTask *pParentTask);
	virtual ~CRULockEquivSetTaskExecutor();

	//----------------------------------//
	//	Public Members
	//----------------------------------//
public:
	//-- Single execution step.
	//-- Implementation of pure virtual functions
	virtual void Work();
	virtual void Init();

	//----------------------------------//
	//	Protected Members
	//----------------------------------//
protected:
	//-- Implementation of pure virtual
	virtual Lng32 GetIpcBufferSize() const
	{
		return 0;	// The task is always performed locally
	}

	//----------------------------------//
	//	Private Members
	//----------------------------------//
private:
	// Not implemented because this executor always runs in the main process

	// These functions serialize/de-serialize the executor's context 
	// for the message communication with the remote server process
	
	// Used in the main process side
	virtual void StoreRequest(CUOFsIpcMessageTranslator &translator) 
	{ 
		RUASSERT(FALSE); 
	}
	virtual void LoadReply(CUOFsIpcMessageTranslator &translator)
	{ 
		RUASSERT(FALSE); 
	}
	
	// Used in the remote process side
	virtual void LoadRequest(CUOFsIpcMessageTranslator &translator)
	{ 
		RUASSERT(FALSE); 
	}
	virtual void StoreReply(CUOFsIpcMessageTranslator &translator)
	{ 
		RUASSERT(FALSE); 
	}

private:
	//-- Prevent copying
	CRULockEquivSetTaskExecutor(const CRULockEquivSetTaskExecutor &other);
	CRULockEquivSetTaskExecutor &operator = 
								(const CRULockEquivSetTaskExecutor &other);

private:
	//-- Work() callees
	void FreezeAllTables(CRULockEquivSetTask *pParentTask);
	void SetTimestampToAllTbls(TInt64 ts);
};

#endif