wasCSharpSQLite – Rev 1
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using System;
using System.Diagnostics;
using System.IO;
using i16 = System.Int16;
using u32 = System.UInt32;
using Pgno = System.UInt32;
namespace Community.CsharpSqlite
{
public partial class Sqlite3
{
/*
** 2008 August 05
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
** This header file defines the interface that the sqlite page cache
** subsystem.
*************************************************************************
** Included in SQLite3 port to C#-SQLite; 2008 Noah B Hart
** C#-SQLite is an independent reimplementation of the SQLite software library
**
** SQLITE_SOURCE_ID: 2010-08-23 18:52:01 42537b60566f288167f1b5864a5435986838e3a3
**
*************************************************************************
*/
#if !_PCACHE_H_
//typedef struct PgHdr PgHdr;
//typedef struct PCache PCache;
/*
** Every page in the cache is controlled by an instance of the following
** structure.
*/
public class PgHdr
{
public byte[] pData; /* Content of this page */
public MemPage pExtra; /* Extra content */
public PgHdr pDirty; /* Transient list of dirty pages */
public Pgno pgno; /* The page number for this page */
public Pager pPager; /* The pager to which this page belongs */
#if SQLITE_CHECK_PAGES || (SQLITE_DEBUG)
public int pageHash; /* Hash of page content */
#endif
public int flags; /* PGHDR flags defined below */
/**********************************************************************
** Elements above are public. All that follows is private to pcache.c
** and should not be accessed by other modules.
*/
public int nRef; /* Number of users of this page */
public PCache pCache; /* Cache that owns this page */
public bool CacheAllocated; /* True, if allocated from cache */
public PgHdr pDirtyNext; /* Next element in list of dirty pages */
public PgHdr pDirtyPrev; /* Previous element in list of dirty pages */
public PgHdr1 pPgHdr1; /* Cache page header this this page */
public static implicit operator bool( PgHdr b )
{
return ( b != null );
}
public void Clear()
{
sqlite3_free( ref this.pData );
this.pData = null;
this.pExtra = null;
this.pDirty = null;
this.pgno = 0;
this.pPager = null;
#if SQLITE_CHECK_PAGES
this.pageHash=0;
#endif
this.flags = 0;
this.nRef = 0;
this.CacheAllocated = false;
this.pCache = null;
this.pDirtyNext = null;
this.pDirtyPrev = null;
this.pPgHdr1 = null;
}
};
/* Bit values for PgHdr.flags */
//#define PGHDR_DIRTY 0x002 /* Page has changed */
//#define PGHDR_NEED_SYNC 0x004 /* Fsync the rollback journal before
// ** writing this page to the database */
//#define PGHDR_NEED_READ 0x008 /* Content is unread */
//#define PGHDR_REUSE_UNLIKELY 0x010 /* A hint that reuse is unlikely */
//#define PGHDR_DONT_WRITE 0x020 /* Do not write content to disk */
const int PGHDR_DIRTY = 0x002; /* Page has changed */
const int PGHDR_NEED_SYNC = 0x004;/* Fsync the rollback journal before
** writing this page to the database */
const int PGHDR_NEED_READ = 0x008;/* Content is unread */
const int PGHDR_REUSE_UNLIKELY = 0x010;/* A hint that reuse is unlikely */
const int PGHDR_DONT_WRITE = 0x020;/* Do not write content to disk */
/* Initialize and shutdown the page cache subsystem */
//int sqlite3PcacheInitialize(void);
//void sqlite3PcacheShutdown(void);
/* Page cache buffer management:
** These routines implement SQLITE_CONFIG_PAGECACHE.
*/
//void sqlite3PCacheBufferSetup(void *, int sz, int n);
/* Create a new pager cache.
** Under memory stress, invoke xStress to try to make pages clean.
** Only clean and unpinned pages can be reclaimed.
*/
//void sqlite3PcacheOpen(
// int szPage, /* Size of every page */
// int szExtra, /* Extra space associated with each page */
// int bPurgeable, /* True if pages are on backing store */
// int (*xStress)(void*, PgHdr*), /* Call to try to make pages clean */
// void pStress, /* Argument to xStress */
// PCache pToInit /* Preallocated space for the PCache */
//);
/* Modify the page-size after the cache has been created. */
//void sqlite3PcacheSetPageSize(PCache *, int);
/* Return the size in bytes of a PCache object. Used to preallocate
** storage space.
*/
//int sqlite3PcacheSize(void);
/* One release per successful fetch. Page is pinned until released.
** Reference counted.
*/
//int sqlite3PcacheFetch(PCache*, Pgno, int createFlag, PgHdr**);
//void sqlite3PcacheRelease(PgHdr*);
//void sqlite3PcacheDrop(PgHdr*); /* Remove page from cache */
//void sqlite3PcacheMakeDirty(PgHdr*); /* Make sure page is marked dirty */
//void sqlite3PcacheMakeClean(PgHdr*); /* Mark a single page as clean */
//void sqlite3PcacheCleanAll(PCache*); /* Mark all dirty list pages as clean */
/* Change a page number. Used by incr-vacuum. */
//void sqlite3PcacheMove(PgHdr*, Pgno);
/* Remove all pages with pgno>x. Reset the cache if x==0 */
//void sqlite3PcacheTruncate(PCache*, Pgno x);
/* Get a list of all dirty pages in the cache, sorted by page number */
//PgHdr *sqlite3PcacheDirtyList(PCache*);
/* Reset and close the cache object */
//void sqlite3PcacheClose(PCache*);
/* Clear flags from pages of the page cache */
//void sqlite3PcacheClearSyncFlags(PCache *);
/* Discard the contents of the cache */
//void sqlite3PcacheClear(PCache*);
/* Return the total number of outstanding page references */
//int sqlite3PcacheRefCount(PCache*);
/* Increment the reference count of an existing page */
//void sqlite3PcacheRef(PgHdr*);
//int sqlite3PcachePageRefcount(PgHdr*);
/* Return the total number of pages stored in the cache */
//int sqlite3PcachePagecount(PCache*);
#if SQLITE_CHECK_PAGES
/* Iterate through all dirty pages currently stored in the cache. This
** interface is only available if SQLITE_CHECK_PAGES is defined when the
** library is built.
*/
//void sqlite3PcacheIterateDirty(PCache pCache, void (*xIter)(PgHdr *));
#endif
/* Set and get the suggested cache-size for the specified pager-cache.
**
** If no global maximum is configured, then the system attempts to limit
** the total number of pages cached by purgeable pager-caches to the sum
** of the suggested cache-sizes.
*/
//void sqlite3PcacheSetCachesize(PCache *, int);
#if SQLITE_TEST
//int sqlite3PcacheGetCachesize(PCache *);
#endif
#if SQLITE_ENABLE_MEMORY_MANAGEMENT
/* Try to return memory used by the pcache module to the main memory heap */
//int sqlite3PcacheReleaseMemory(int);
#endif
#if SQLITE_TEST
//void sqlite3PcacheStats(int*,int*,int*,int*);
#endif
//void sqlite3PCacheSetDefault(void);
#endif //* _PCACHE_H_ */
}
}