Tree-M/MT/MTfile.h

/*********************************************************************
*                                                                    *
* Copyright (c) 1997,1998, 1999                                      *
* Multimedia DB Group and DEIS - CSITE-CNR,                          *
* University of Bologna, Bologna, ITALY.                             *
*                                                                    *
* All Rights Reserved.                                               *
*                                                                    *
* Permission to use, copy, and distribute this software and its      *
* documentation for NON-COMMERCIAL purposes and without fee is       *
* hereby granted provided  that this copyright notice appears in     *
* all copies.                                                        *
*                                                                    *
* THE AUTHORS MAKE NO REPRESENTATIONS OR WARRANTIES ABOUT THE        *
* SUITABILITY OF THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING  *
* BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY,      *
* FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. THE AUTHOR  *
* SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A      *
* RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS    *
* DERIVATIVES.                                                       *
*                                                                    *
*********************************************************************/

#ifndef MTFILE_H
#define MTFILE_H

#include "GiSTstore.h"

//      MTfile is a simple storage class for GiSTs to work over 
//      UNIX/NT files. It is a copy of the GiSTfile class.

class MTfile: public GiSTstore {
        unsigned int page;
        struct Page {
          GiSTpage page;
          char *buf;
          int dirty;
          int seq;
        };
        Page *cache;
        unsigned int cachesize;

        Page *newpage(GiSTpage page);
        Page *findpage(GiSTpage page);
        void flushpage(Page *p);
public:
        void setcache(unsigned int pages);

        MTfile(unsigned int pagesize)
          : GiSTstore(), page(pagesize), cachesize(0)
          {
            setcache (16);
          }

        ~MTfile();

        void Create(const char *filename);
        void Open(const char *filename);
        void Close();

        void Read(GiSTpage page, char *buf);
        void Write(GiSTpage page, const char *buf);
        GiSTpage Allocate();
        void Deallocate(GiSTpage page);
        void Sync();
        int PageSize() const { return page; }

private:
        int fileHandle;
};

#endif
Revision:	1.2
Committed:	Wed May 23 02:11:14 2001 UTC (23 years ago) by root
Content type:	text/plain
Branch:	MAIN
CVS Tags:	HEAD
Changes since 1.1:	+24 -4 lines
Log Message:	* empty log message *
#	Content
1	/*********************************************************************
2	* *
3	* Copyright (c) 1997,1998, 1999 *
4	* Multimedia DB Group and DEIS - CSITE-CNR, *
5	* University of Bologna, Bologna, ITALY. *
6	* *
7	* All Rights Reserved. *
8	* *
9	* Permission to use, copy, and distribute this software and its *
10	* documentation for NON-COMMERCIAL purposes and without fee is *
11	* hereby granted provided that this copyright notice appears in *
12	* all copies. *
13	* *
14	* THE AUTHORS MAKE NO REPRESENTATIONS OR WARRANTIES ABOUT THE *
15	* SUITABILITY OF THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING *
16	* BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, *
17	* FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. THE AUTHOR *
18	* SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A *
19	* RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS *
20	* DERIVATIVES. *
21	* *
22	*********************************************************************/
23
24	#ifndef MTFILE_H
25	#define MTFILE_H
26
27	#include "GiSTstore.h"
28
29	// MTfile is a simple storage class for GiSTs to work over
30	// UNIX/NT files. It is a copy of the GiSTfile class.
31
32	class MTfile: public GiSTstore {
33	unsigned int page;
34	struct Page {
35	GiSTpage page;
36	char *buf;
37	int dirty;
38	int seq;
39	};
40	Page *cache;
41	unsigned int cachesize;
42
43	Page *newpage(GiSTpage page);
44	Page *findpage(GiSTpage page);
45	void flushpage(Page *p);
46	public:
47	void setcache(unsigned int pages);
48
49	MTfile(unsigned int pagesize)
50	: GiSTstore(), page(pagesize), cachesize(0)
51	{
52	setcache (16);
53	}
54
55	~MTfile();
56
57	void Create(const char *filename);
58	void Open(const char *filename);
59	void Close();
60
61	void Read(GiSTpage page, char *buf);
62	void Write(GiSTpage page, const char *buf);
63	GiSTpage Allocate();
64	void Deallocate(GiSTpage page);
65	void Sync();
66	int PageSize() const { return page; }
67
68	private:
69	int fileHandle;
70	};
71
72	#endif