~drizzle-trunk/drizzle/development

/* Copyright (C) 2008 PrimeBase Technologies GmbH, Germany

 *

 * PrimeBase Media Stream for MySQL

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

 *

 * Original author: Paul McCullagh

 * Continued development: Barry Leslie

 *

 * 2007-07-03

 *

 * H&G2JCtL

 *

 * Temporary BLOB log.

 *

 * Temporary BLOBs are BLOBs that are to be deleted after an certain

 * expiry time.

 *

 * The temporary log is also used to schedule asynchronous operations to be performed

 * on the BLOB such as uploading it to a cloud.

 *

 * Temporary BLOBs are referenced by the temporary log.

 */

#ifndef __TEMPLOG_MS_H__

#define __TEMPLOG_MS_H__

#include "cslib/CSDefs.h"

#include "cslib/CSFile.h"

#include "cslib/CSStream.h"

#include "defs_ms.h"

class MSOpenTable;

class MSDatabase;

class MSTempLog;

// Change history:

// April 6 2009:

// Changed MS_TEMP_LOG_MAGIC and MS_TEMP_LOG_VERSION

// when the disk size of ti_type_1 was changed from

// CSDiskValue4 to CSDiskValue1.

#define MS_TEMP_LOG_MAGIC			0xF9E6D7C9

#define MS_TEMP_LOG_VERSION			3

#define MS_TEMP_LOG_HEAD_SIZE		32

#define MS_TL_BLOB_REF				1

#define MS_TL_REPO_REF				2		

#define MS_TL_TABLE_REF				3

typedef struct MSTempLogHead {

	CSDiskValue4			th_magic_4;							/* Table magic number. */

	CSDiskValue2			th_version_2;						/* The header version. */

	CSDiskValue2			th_head_size_2;						/* The size of the header. */

	CSDiskValue2			th_rec_size_2;						/* The size of a temp log record. */

	CSDiskValue4			th_reserved_4;

} MSTempLogHeadRec, *MSTempLogHeadPtr;

typedef struct MSTempLogItem {

	CSDiskValue1			ti_type_1;							/* 1 = BLOB reference, 2 = Repository reference, 3 = Table reference */

	CSDiskValue4			ti_table_id_4;						/* Table ID (non-zero if valid). */

	CSDiskValue6			ti_blob_id_6;						/* Blob ID (non-zero if valid). */

	CSDiskValue4			ti_auth_code_4;						/* To make sure we do not delete the wrong thing. */

	CSDiskValue4			ti_time_4;							/* The time of deletion/creation */

} MSTempLogItemRec, *MSTempLogItemPtr;

class MSTempLogFile : public CSReadBufferedFile {

public:

	uint32_t		myTempLogID;

	MSTempLog	*myTempLog;

	MSTempLogFile();

	~MSTempLogFile();

	friend class MSTempLog;

private:

	static MSTempLogFile *newTempLogFile(uint32_t id, MSTempLog *temp_log, CSFile *path);

};

class MSTempLog : public CSRefObject {

public:

	uint32_t		myLogID;

	off64_t		myTempLogSize;

	int			myTemplogRecSize;

	size_t		myTempLogHeadSize;

	MSTempLog(uint32_t id, MSDatabase *db, off64_t file_size);

	virtual ~MSTempLog();

	void deleteLog();

	CSPath *getLogPath();

	MSTempLogFile *openTempLog();

#ifdef DEBUG

//	virtual void retain() {

//		CSRefObject::retain();

//		printf("MSTempLog retained %d\n", iRefCount);

//	}

//

//	virtual void release() {

//		printf("MSTempLog released %d\n", iRefCount);

//		CSRefObject::release();

//	}

#endif

	friend class MSTempLogThread;

private:

	MSDatabase		*iLogDatabase;

	bool			iDeleteLog;

public:

	static time_t adjustWaitTime(time_t then, time_t now);

};

class MSTempLogThread : public CSDaemon {

public:

	MSTempLogThread(time_t wait_time, MSDatabase *db);

	virtual ~MSTempLogThread(){} // Do nothing here because 'self' will no longer be valid, use completeWork().

	void close();

	virtual bool doWork();

	virtual void *completeWork();

private:

	bool try_ReleaseBLOBReference(CSThread *self, CSStringBuffer *buffer, uint32_t tab_id, int type, uint64_t blob_id, uint32_t auth_code);

	MSDatabase			*iTempLogDatabase;

	MSTempLogFile		*iTempLogFile;

	size_t				iLogRecSize;

	off64_t				iLogOffset;

};

#endif