/*
** Parameter zSrcData points to a buffer containing the data for
** page iSrcPg from the source database. Copy this data into the
** destination database.
*/
static int backupOnePage(sqlite3_backup p, Pgno iSrcPg, byte[] zSrcData)
{
Pager pDestPager = sqlite3BtreePager(p.pDest);
int nSrcPgsz = sqlite3BtreeGetPageSize(p.pSrc);
int nDestPgsz = sqlite3BtreeGetPageSize(p.pDest);
int nCopy = MIN(nSrcPgsz, nDestPgsz);
i64 iEnd = (i64)iSrcPg * (i64)nSrcPgsz;
int rc = SQLITE_OK;
i64 iOff;
Debug.Assert(p.bDestLocked != 0);
Debug.Assert(!isFatalError(p.rc));
Debug.Assert(iSrcPg != PENDING_BYTE_PAGE(p.pSrc.pBt));
Debug.Assert(zSrcData != null);
/* Catch the case where the destination is an in-memory database and the
** page sizes of the source and destination differ.
*/
if (nSrcPgsz != nDestPgsz && sqlite3PagerIsMemdb(sqlite3BtreePager(p.pDest)))
{
rc = SQLITE_READONLY;
}
/* This loop runs once for each destination page spanned by the source
** page. For each iteration, variable iOff is set to the byte offset
** of the destination page.
*/
for (iOff = iEnd - (i64)nSrcPgsz; rc == SQLITE_OK && iOff < iEnd; iOff += nDestPgsz)
{
DbPage pDestPg = null;
u32 iDest = (u32)(iOff / nDestPgsz) + 1;
if (iDest == PENDING_BYTE_PAGE(p.pDest.pBt))
{
continue;
}
if (SQLITE_OK == (rc = sqlite3PagerGet(pDestPager, iDest, ref pDestPg)) &&
SQLITE_OK == (rc = sqlite3PagerWrite(pDestPg))
)
{
//string zIn = &zSrcData[iOff%nSrcPgsz];
byte[] zDestData = sqlite3PagerGetData(pDestPg);
//string zOut = &zDestData[iOff % nDestPgsz];
/* Copy the data from the source page into the destination page.
** Then clear the Btree layer MemPage.isInit flag. Both this module
** and the pager code use this trick (clearing the first byte
** of the page 'extra' space to invalidate the Btree layers
** cached parse of the page). MemPage.isInit is marked
** "MUST BE FIRST" for this purpose.
*/
Buffer.BlockCopy(zSrcData, (int)(iOff % nSrcPgsz), zDestData, (int)(iOff % nDestPgsz), nCopy); // memcpy( zOut, zIn, nCopy );
sqlite3PagerGetExtra(pDestPg).isInit = 0; // ( sqlite3PagerGetExtra( pDestPg ) )[0] = 0;
}
sqlite3PagerUnref(pDestPg);
}
return(rc);
}
/// <summary>
/// 获取页面类型信息
/// </summary>
/// <returns></returns>
private PageMenu getPageMenu()
{
var dbPage = new DbPage();
PageMenu result = null;
string url = this.GetPageUrl();
result = dbPage.GetPageMenu(url);
if (result == null)
{
PageMenu m = new PageMenu();
m.ShowName = string.IsNullOrWhiteSpace(this.Title) ? "请设置名称" : this.Title;
m.PageUrl = url;
dbPage.AddPageMenu(m);
return(getPageMenu());
}
else
{
return(result);
}
}
protected void GrpSiz_Changed(object sender, EventArgs e)
{
TextBox txtGrpSiz = sender as TextBox;
GridViewRow row = txtGrpSiz.NamingContainer as GridViewRow;
AjaxControlToolkit.ComboBox combo = row.FindControl("comboEdit3") as AjaxControlToolkit.ComboBox;
string postbackControlId = "";
try
{
if (ScriptManager.GetCurrent(txtGrpSiz.Page).IsInAsyncPostBack)
{
postbackControlId = DbPage.GetAsyncPostBackControlID(txtGrpSiz.Page);
}
else
{
postbackControlId = DbPage.GetPostBackControl(txtGrpSiz.Page).ID;
}
}
catch (Exception) { }
if (!postbackControlId.EndsWith(combo.ID))
{
int num = 0;
try
{
num = int.Parse(txtGrpSiz.Text);
if (num == -1)
{
combo.SelectedValue = "Delay";
}
else if (num > 0)
{
combo.SelectedValue = "Standard";
}
//txtGrpSiz.Text = 10 + "";
}
catch (Exception) { }
}
}
/*
** During a rollback, when the pager reloads information into the cache
** so that the cache is restored to its original state at the start of
** the transaction, for each page restored this routine is called.
**
** This routine needs to reset the extra data section at the end of the
** page to agree with the restored data.
*/
static void pageReinit( DbPage pData )
{
MemPage pPage;
pPage = sqlite3PagerGetExtra( pData );
Debug.Assert( sqlite3PagerPageRefcount( pData ) > 0 );
if ( pPage.isInit != 0 )
{
Debug.Assert( sqlite3_mutex_held( pPage.pBt.mutex ) );
pPage.isInit = 0;
if ( sqlite3PagerPageRefcount( pData ) > 1 )
{
/* pPage might not be a btree page; it might be an overflow page
** or ptrmap page or a free page. In those cases, the following
** call to btreeInitPage() will likely return SQLITE_CORRUPT.
** But no harm is done by this. And it is very important that
** btreeInitPage() be called on every btree page so we make
** the call for every page that comes in for re-initing. */
btreeInitPage( pPage );
}
}
}
/*
** Convert a DbPage obtained from the pager into a MemPage used by
** the btree layer.
*/
static MemPage btreePageFromDbPage( DbPage pDbPage, Pgno pgno, BtShared pBt )
{
MemPage pPage = (MemPage)sqlite3PagerGetExtra( pDbPage );
pPage.aData = sqlite3PagerGetData( pDbPage );
pPage.pDbPage = pDbPage;
pPage.pBt = pBt;
pPage.pgno = pgno;
pPage.hdrOffset = (u8)( pPage.pgno == 1 ? 100 : 0 );
return pPage;
}
/*
** Return a pointer to the Pager.nExtra bytes of "extra" space
** allocated along with the specified page.
*/
static MemPage sqlite3PagerGetExtra( DbPage pPg )
{
return pPg.pExtra;
}
/*
** Return a pointer to the data for the specified page.
*/
static byte[] sqlite3PagerGetData( DbPage pPg )
{
Debug.Assert( pPg.nRef > 0 || pPg.pPager.memDb != 0 );
return pPg.pData;
}
/*
** Move the page pPg to location pgno in the file.
**
** There must be no references to the page previously located at
** pgno (which we call pPgOld) though that page is allowed to be
** in cache. If the page previously located at pgno is not already
** in the rollback journal, it is not put there by by this routine.
**
** References to the page pPg remain valid. Updating any
** meta-data associated with pPg (i.e. data stored in the nExtra bytes
** allocated along with the page) is the responsibility of the caller.
**
** A transaction must be active when this routine is called. It used to be
** required that a statement transaction was not active, but this restriction
** has been removed (CREATE INDEX needs to move a page when a statement
** transaction is active).
**
** If the fourth argument, isCommit, is non-zero, then this page is being
** moved as part of a database reorganization just before the transaction
** is being committed. In this case, it is guaranteed that the database page
** pPg refers to will not be written to again within this transaction.
**
** This function may return SQLITE_NOMEM or an IO error code if an error
** occurs. Otherwise, it returns SQLITE_OK.
*/
static int sqlite3PagerMovepage( Pager pPager, DbPage pPg, u32 pgno, int isCommit )
{
PgHdr pPgOld; /* The page being overwritten. */
u32 needSyncPgno = 0; /* Old value of pPg.pgno, if sync is required */
int rc; /* Return code */
Pgno origPgno; /* The original page number */
Debug.Assert( pPg.nRef > 0 );
/* In order to be able to rollback, an in-memory database must journal
** the page we are moving from.
*/
if (
#if SQLITE_OMIT_MEMORYDB
1==MEMDB
#else
pPager.memDb != 0
#endif
)
{
rc = sqlite3PagerWrite( pPg );
if ( rc != 0 ) return rc;
}
/* If the page being moved is dirty and has not been saved by the latest
** savepoint, then save the current contents of the page into the
** sub-journal now. This is required to handle the following scenario:
**
** BEGIN;
** <journal page X, then modify it in memory>
** SAVEPOINT one;
** <Move page X to location Y>
** ROLLBACK TO one;
**
** If page X were not written to the sub-journal here, it would not
** be possible to restore its contents when the "ROLLBACK TO one"
** statement were is processed.
**
** subjournalPage() may need to allocate space to store pPg.pgno into
** one or more savepoint bitvecs. This is the reason this function
** may return SQLITE_NOMEM.
*/
if ( ( pPg.flags & PGHDR_DIRTY ) != 0
&& subjRequiresPage( pPg )
&& SQLITE_OK != ( rc = subjournalPage( pPg ) )
)
{
return rc;
}
PAGERTRACE( "MOVE %d page %d (needSync=%d) moves to %d\n",
PAGERID( pPager ), pPg.pgno, ( pPg.flags & PGHDR_NEED_SYNC ) != 0 ? 1 : 0, pgno );
IOTRACE( "MOVE %p %d %d\n", pPager, pPg.pgno, pgno );
/* If the journal needs to be sync()ed before page pPg.pgno can
** be written to, store pPg.pgno in local variable needSyncPgno.
**
** If the isCommit flag is set, there is no need to remember that
** the journal needs to be sync()ed before database page pPg.pgno
** can be written to. The caller has already promised not to write to it.
*/
if ( ( ( pPg.flags & PGHDR_NEED_SYNC ) != 0 ) && 0 == isCommit )
{
needSyncPgno = pPg.pgno;
Debug.Assert( pageInJournal( pPg ) || pPg.pgno > pPager.dbOrigSize );
Debug.Assert( ( pPg.flags & PGHDR_DIRTY ) != 0 );
Debug.Assert( pPager.needSync );
}
/* If the cache contains a page with page-number pgno, remove it
** from its hash chain. Also, if the PgHdr.needSync was set for
** page pgno before the 'move' operation, it needs to be retained
** for the page moved there.
*/
pPg.flags &= ~PGHDR_NEED_SYNC;
pPgOld = pager_lookup( pPager, pgno );
Debug.Assert( null == pPgOld || pPgOld.nRef == 1 );
if ( pPgOld != null )
{
pPg.flags |= ( pPgOld.flags & PGHDR_NEED_SYNC );
if (
#if SQLITE_OMIT_MEMORYDB
1==MEMDB
#else
pPager.memDb != 0
#endif
)
{
/* Do not discard pages from an in-memory database since we might
** need to rollback later. Just move the page out of the way. */
Debug.Assert( pPager.dbSizeValid );
sqlite3PcacheMove( pPgOld, pPager.dbSize + 1 );
}
else
{
sqlite3PcacheDrop( pPgOld );
}
}
origPgno = pPg.pgno;
sqlite3PcacheMove( pPg, pgno );
sqlite3PcacheMakeDirty( pPg );
pPager.dbModified = true;
if ( needSyncPgno != 0 )
{
/* If needSyncPgno is non-zero, then the journal file needs to be
** sync()ed before any data is written to database file page needSyncPgno.
** Currently, no such page exists in the page-cache and the
** "is journaled" bitvec flag has been set. This needs to be remedied by
** loading the page into the pager-cache and setting the PgHdr.needSync
** flag.
**
** If the attempt to load the page into the page-cache fails, (due
** to a malloc() or IO failure), clear the bit in the pInJournal[]
** array. Otherwise, if the page is loaded and written again in
** this transaction, it may be written to the database file before
** it is synced into the journal file. This way, it may end up in
** the journal file twice, but that is not a problem.
**
** The sqlite3PagerGet() call may cause the journal to sync. So make
** sure the Pager.needSync flag is set too.
*/
PgHdr pPgHdr = null;
Debug.Assert( pPager.needSync );
rc = sqlite3PagerGet( pPager, needSyncPgno, ref pPgHdr );
if ( rc != SQLITE_OK )
{
if ( needSyncPgno <= pPager.dbOrigSize )
{
Debug.Assert( pPager.pTmpSpace != null );
u32[] pTemp = new u32[pPager.pTmpSpace.Length];
sqlite3BitvecClear( pPager.pInJournal, needSyncPgno, pTemp );//pPager.pTmpSpace );
}
return rc;
}
pPager.needSync = true;
Debug.Assert( pPager.noSync == false &&
#if SQLITE_OMIT_MEMORYDB
0==MEMDB
#else
0 == pPager.memDb
#endif
);
pPgHdr.flags |= PGHDR_NEED_SYNC;
sqlite3PcacheMakeDirty( pPgHdr );
sqlite3PagerUnref( pPgHdr );
}
/*
** For an in-memory database, make sure the original page continues
** to exist, in case the transaction needs to roll back. Use pPgOld
** as the original page since it has already been allocated.
*/
if (
#if SQLITE_OMIT_MEMORYDB
MEMDB != 0
#else
pPager.memDb != 0
#endif
)
{
sqlite3PcacheMove( pPgOld, origPgno );
sqlite3PagerUnref( pPgOld );
}
return SQLITE_OK;
}
/*
** Return the number of references to the specified page.
*/
static int sqlite3PagerPageRefcount( DbPage pPage )
{
return sqlite3PcachePageRefcount( pPage );
}
static Pgno sqlite3PagerPagenumber( DbPage pPg ) { return pPg.pgno; }
/*
** Copy nPage pages from the source b-tree to the destination.
*/
static public int sqlite3_backup_step(sqlite3_backup p, int nPage)
{
int rc;
int destMode; /* Destination journal mode */
int pgszSrc = 0; /* Source page size */
int pgszDest = 0; /* Destination page size */
sqlite3_mutex_enter(p.pSrcDb.mutex);
sqlite3BtreeEnter(p.pSrc);
if (p.pDestDb != null)
{
sqlite3_mutex_enter(p.pDestDb.mutex);
}
rc = p.rc;
if (!isFatalError(rc))
{
Pager pSrcPager = sqlite3BtreePager(p.pSrc); /* Source pager */
Pager pDestPager = sqlite3BtreePager(p.pDest); /* Dest pager */
int ii; /* Iterator variable */
Pgno nSrcPage = 0; /* Size of source db in pages */
int bCloseTrans = 0; /* True if src db requires unlocking */
/* If the source pager is currently in a write-transaction, return
** SQLITE_BUSY immediately.
*/
if (p.pDestDb != null && p.pSrc.pBt.inTransaction == TRANS_WRITE)
{
rc = SQLITE_BUSY;
}
else
{
rc = SQLITE_OK;
}
/* Lock the destination database, if it is not locked already. */
if (SQLITE_OK == rc && p.bDestLocked == 0 &&
SQLITE_OK == (rc = sqlite3BtreeBeginTrans(p.pDest, 2))
)
{
p.bDestLocked = 1;
sqlite3BtreeGetMeta(p.pDest, BTREE_SCHEMA_VERSION, ref p.iDestSchema);
}
/* If there is no open read-transaction on the source database, open
** one now. If a transaction is opened here, then it will be closed
** before this function exits.
*/
if (rc == SQLITE_OK && !sqlite3BtreeIsInReadTrans(p.pSrc))
{
rc = sqlite3BtreeBeginTrans(p.pSrc, 0);
bCloseTrans = 1;
}
/* Do not allow backup if the destination database is in WAL mode
** and the page sizes are different between source and destination */
pgszSrc = sqlite3BtreeGetPageSize(p.pSrc);
pgszDest = sqlite3BtreeGetPageSize(p.pDest);
destMode = sqlite3PagerGetJournalMode(sqlite3BtreePager(p.pDest));
if (SQLITE_OK == rc && destMode == PAGER_JOURNALMODE_WAL && pgszSrc != pgszDest)
{
rc = SQLITE_READONLY;
}
/* Now that there is a read-lock on the source database, query the
** source pager for the number of pages in the database.
*/
nSrcPage = sqlite3BtreeLastPage(p.pSrc);
Debug.Assert(nSrcPage >= 0);
for (ii = 0; (nPage < 0 || ii < nPage) && p.iNext <= nSrcPage && 0 == rc; ii++)
{
Pgno iSrcPg = p.iNext; /* Source page number */
if (iSrcPg != PENDING_BYTE_PAGE(p.pSrc.pBt))
{
DbPage pSrcPg = null; /* Source page object */
rc = sqlite3PagerGet(pSrcPager, (u32)iSrcPg, ref pSrcPg);
if (rc == SQLITE_OK)
{
rc = backupOnePage(p, iSrcPg, sqlite3PagerGetData(pSrcPg));
sqlite3PagerUnref(pSrcPg);
}
}
p.iNext++;
}
if (rc == SQLITE_OK)
{
p.nPagecount = nSrcPage;
p.nRemaining = (nSrcPage + 1 - p.iNext);
if (p.iNext > nSrcPage)
{
rc = SQLITE_DONE;
}
else if (0 == p.isAttached)
{
attachBackupObject(p);
}
}
/* Update the schema version field in the destination database. This
** is to make sure that the schema-version really does change in
** the case where the source and destination databases have the
** same schema version.
*/
if (rc == SQLITE_DONE &&
(rc = sqlite3BtreeUpdateMeta(p.pDest, 1, p.iDestSchema + 1)) == SQLITE_OK
)
{
Pgno nDestTruncate;
if (p.pDestDb != null)
{
sqlite3ResetInternalSchema(p.pDestDb, -1);
}
/* Set nDestTruncate to the final number of pages in the destination
** database. The complication here is that the destination page
** size may be different to the source page size.
**
** If the source page size is smaller than the destination page size,
** round up. In this case the call to sqlite3OsTruncate() below will
** fix the size of the file. However it is important to call
** sqlite3PagerTruncateImage() here so that any pages in the
** destination file that lie beyond the nDestTruncate page mark are
** journalled by PagerCommitPhaseOne() before they are destroyed
** by the file truncation.
*/
Debug.Assert(pgszSrc == sqlite3BtreeGetPageSize(p.pSrc));
Debug.Assert(pgszDest == sqlite3BtreeGetPageSize(p.pDest));
if (pgszSrc < pgszDest)
{
int ratio = pgszDest / pgszSrc;
nDestTruncate = (Pgno)((nSrcPage + ratio - 1) / ratio);
if (nDestTruncate == (int)PENDING_BYTE_PAGE(p.pDest.pBt))
{
nDestTruncate--;
}
}
else
{
nDestTruncate = (Pgno)(nSrcPage * (pgszSrc / pgszDest));
}
sqlite3PagerTruncateImage(pDestPager, nDestTruncate);
if (pgszSrc < pgszDest)
{
/* If the source page-size is smaller than the destination page-size,
** two extra things may need to happen:
**
** * The destination may need to be truncated, and
**
** * Data stored on the pages immediately following the
** pending-byte page in the source database may need to be
** copied into the destination database.
*/
int iSize = (int)(pgszSrc * nSrcPage);
sqlite3_file pFile = sqlite3PagerFile(pDestPager);
i64 iOff;
i64 iEnd;
Debug.Assert(pFile != null);
Debug.Assert((i64)nDestTruncate * (i64)pgszDest >= iSize || (
nDestTruncate == (int)(PENDING_BYTE_PAGE(p.pDest.pBt) - 1) &&
iSize >= PENDING_BYTE && iSize <= PENDING_BYTE + pgszDest
));
/* This call ensures that all data required to recreate the original
** database has been stored in the journal for pDestPager and the
** journal synced to disk. So at this point we may safely modify
** the database file in any way, knowing that if a power failure
** occurs, the original database will be reconstructed from the
** journal file. */
rc = sqlite3PagerCommitPhaseOne(pDestPager, null, true);
/* Write the extra pages and truncate the database file as required. */
iEnd = MIN(PENDING_BYTE + pgszDest, iSize);
for (
iOff = PENDING_BYTE + pgszSrc;
rc == SQLITE_OK && iOff < iEnd;
iOff += pgszSrc
)
{
PgHdr pSrcPg = null;
u32 iSrcPg = (u32)((iOff / pgszSrc) + 1);
rc = sqlite3PagerGet(pSrcPager, iSrcPg, ref pSrcPg);
if (rc == SQLITE_OK)
{
byte[] zData = sqlite3PagerGetData(pSrcPg);
rc = sqlite3OsWrite(pFile, zData, pgszSrc, iOff);
}
sqlite3PagerUnref(pSrcPg);
}
if (rc == SQLITE_OK)
{
rc = backupTruncateFile(pFile, (int)iSize);
}
/* Sync the database file to disk. */
if (rc == SQLITE_OK)
{
rc = sqlite3PagerSync(pDestPager);
}
}
else
{
rc = sqlite3PagerCommitPhaseOne(pDestPager, null, false);
}
/* Finish committing the transaction to the destination database. */
if (SQLITE_OK == rc &&
SQLITE_OK == (rc = sqlite3BtreeCommitPhaseTwo(p.pDest, 0))
)
{
rc = SQLITE_DONE;
}
}
/* If bCloseTrans is true, then this function opened a read transaction
** on the source database. Close the read transaction here. There is
** no need to check the return values of the btree methods here, as
** "committing" a read-only transaction cannot fail.
*/
if (bCloseTrans != 0)
{
#if !NDEBUG || SQLITE_COVERAGE_TEST
//TESTONLY( int rc2 );
//TESTONLY( rc2 = ) sqlite3BtreeCommitPhaseOne(p.pSrc, 0);
//TESTONLY( rc2 |= ) sqlite3BtreeCommitPhaseTwo(p.pSrc);
int rc2;
rc2 = sqlite3BtreeCommitPhaseOne(p.pSrc, string.Empty);
rc2 |= sqlite3BtreeCommitPhaseTwo(p.pSrc, 0);
Debug.Assert(rc2 == SQLITE_OK);
#else
sqlite3BtreeCommitPhaseOne(p.pSrc, null);
sqlite3BtreeCommitPhaseTwo(p.pSrc, 0);
#endif
}
if (rc == SQLITE_IOERR_NOMEM)
{
rc = SQLITE_NOMEM;
}
p.rc = rc;
}
if (p.pDestDb != null)
{
sqlite3_mutex_leave(p.pDestDb.mutex);
}
sqlite3BtreeLeave(p.pSrc);
sqlite3_mutex_leave(p.pSrcDb.mutex);
return(rc);
}
/*
** Mark a data page as writeable. This routine must be called before
** making changes to a page. The caller must check the return value
** of this function and be careful not to change any page data unless
** this routine returns SQLITE_OK.
**
** The difference between this function and pager_write() is that this
** function also deals with the special case where 2 or more pages
** fit on a single disk sector. In this case all co-resident pages
** must have been written to the journal file before returning.
**
** If an error occurs, SQLITE_NOMEM or an IO error code is returned
** as appropriate. Otherwise, SQLITE_OK.
*/
static int sqlite3PagerWrite( DbPage pDbPage )
{
int rc = SQLITE_OK;
PgHdr pPg = pDbPage;
Pager pPager = pPg.pPager;
u32 nPagePerSector = (u32)( pPager.sectorSize / pPager.pageSize );
if ( nPagePerSector > 1 )
{
Pgno nPageCount = 0; /* Total number of pages in database file */
Pgno pg1; /* First page of the sector pPg is located on. */
Pgno nPage; /* Number of pages starting at pg1 to journal */
int ii; /* Loop counter */
bool needSync = false; /* True if any page has PGHDR_NEED_SYNC */
/* Set the doNotSync flag to 1. This is because we cannot allow a journal
** header to be written between the pages journaled by this function.
*/
Debug.Assert(
#if SQLITE_OMIT_MEMORYDB
0==MEMDB
#else
0 == pPager.memDb
#endif
);
Debug.Assert( !pPager.doNotSync );
pPager.doNotSync = true;
/* This trick assumes that both the page-size and sector-size are
** an integer power of 2. It sets variable pg1 to the identifier
** of the first page of the sector pPg is located on.
*/
pg1 = (u32)( ( pPg.pgno - 1 ) & ~( nPagePerSector - 1 ) ) + 1;
sqlite3PagerPagecount( pPager, ref nPageCount );
if ( pPg.pgno > nPageCount )
{
nPage = (u32)( pPg.pgno - pg1 ) + 1;
}
else if ( ( pg1 + nPagePerSector - 1 ) > nPageCount )
{
nPage = (u32)( nPageCount + 1 - pg1 );
}
else
{
nPage = nPagePerSector;
}
Debug.Assert( nPage > 0 );
Debug.Assert( pg1 <= pPg.pgno );
Debug.Assert( ( pg1 + nPage ) > pPg.pgno );
for ( ii = 0; ii < nPage && rc == SQLITE_OK; ii++ )
{
u32 pg = (u32)( pg1 + ii );
PgHdr pPage = new PgHdr();
if ( pg == pPg.pgno || sqlite3BitvecTest( pPager.pInJournal, pg ) == 0 )
{
if ( pg != ( ( PENDING_BYTE / ( pPager.pageSize ) ) + 1 ) ) //PAGER_MJ_PGNO(pPager))
{
rc = sqlite3PagerGet( pPager, pg, ref pPage );
if ( rc == SQLITE_OK )
{
rc = pager_write( pPage );
if ( ( pPage.flags & PGHDR_NEED_SYNC ) != 0 )
{
needSync = true;
Debug.Assert( pPager.needSync );
}
sqlite3PagerUnref( pPage );
}
}
}
else if ( ( pPage = pager_lookup( pPager, pg ) ) != null )
{
if ( ( pPage.flags & PGHDR_NEED_SYNC ) != 0 )
{
needSync = true;
}
sqlite3PagerUnref( pPage );
}
}
/* If the PGHDR_NEED_SYNC flag is set for any of the nPage pages
** starting at pg1, then it needs to be set for all of them. Because
** writing to any of these nPage pages may damage the others, the
** journal file must contain sync()ed copies of all of them
** before any of them can be written out to the database file.
*/
if ( rc == SQLITE_OK && needSync )
{
Debug.Assert(
#if SQLITE_OMIT_MEMORYDB
0==MEMDB
#else
0 == pPager.memDb
#endif
&& pPager.noSync == false );
for ( ii = 0; ii < nPage; ii++ )
{
PgHdr pPage = pager_lookup( pPager, (u32)( pg1 + ii ) );
if ( pPage != null )
{
pPage.flags |= PGHDR_NEED_SYNC;
sqlite3PagerUnref( pPage );
}
}
Debug.Assert( pPager.needSync );
}
Debug.Assert( pPager.doNotSync );
pPager.doNotSync = false;
}
else
{
rc = pager_write( pDbPage );
}
return rc;
}
/*
** Release a page reference.
**
** If the number of references to the page drop to zero, then the
** page is added to the LRU list. When all references to all pages
** are released, a rollback occurs and the lock on the database is
** removed.
*/
static void sqlite3PagerUnref( DbPage pPg )
{
if ( pPg != null )
{
Pager pPager = pPg.pPager;
sqlite3PcacheRelease( pPg );
pagerUnlockIfUnused( pPager );
}
}
static int sqlite3PagerAcquire(
Pager pPager, /* The pager open on the database file */
u32 pgno, /* Page number to fetch */
ref DbPage ppPage, /* Write a pointer to the page here */
u8 noContent /* Do not bother reading content from disk if true */
)
{
int rc;
PgHdr pPg = null;
Debug.Assert( assert_pager_state( pPager ) );
Debug.Assert( pPager.state > PAGER_UNLOCK );
if ( pgno == 0 )
{
return SQLITE_CORRUPT_BKPT();
}
/* If the pager is in the error state, return an error immediately.
** Otherwise, request the page from the PCache layer. */
if ( pPager.errCode != SQLITE_OK && pPager.errCode != SQLITE_FULL )
{
rc = pPager.errCode;
}
else
{
rc = sqlite3PcacheFetch( pPager.pPCache, pgno, 1, ref ppPage );
}
if ( rc != SQLITE_OK )
{
/* Either the call to sqlite3PcacheFetch() returned an error or the
** pager was already in the error-state when this function was called.
** Set pPg to 0 and jump to the exception handler. */
pPg = null;
goto pager_acquire_err;
}
Debug.Assert( ( ppPage ).pgno == pgno );
Debug.Assert( ( ppPage ).pPager == pPager || ( ppPage ).pPager == null );
if ( ( ppPage ).pPager != null )
{
/* In this case the pcache already contains an initialized copy of
** the page. Return without further ado. */
Debug.Assert( pgno <= PAGER_MAX_PGNO && pgno != PAGER_MJ_PGNO( pPager ) );
PAGER_INCR( ref pPager.nHit );
return SQLITE_OK;
}
else
{
/* The pager cache has created a new page. Its content needs to
** be initialized. */
Pgno nMax = 0;
#if SQLITE_TEST
PAGER_INCR( ref pPager.nMiss );
#endif
pPg = ppPage;
pPg.pPager = pPager;
pPg.pExtra = new MemPage();//memset(pPg.pExtra, 0, pPager.nExtra);
/* The maximum page number is 2^31. Return SQLITE_CORRUPT if a page
** number greater than this, or the unused locking-page, is requested. */
if ( pgno > PAGER_MAX_PGNO || pgno == PAGER_MJ_PGNO( pPager ) )
{
rc = SQLITE_CORRUPT_BKPT();
goto pager_acquire_err;
}
rc = sqlite3PagerPagecount( pPager, ref nMax );
if ( rc != SQLITE_OK )
{
goto pager_acquire_err;
}
if (
#if SQLITE_OMIT_MEMORYDB
1==MEMDB
#else
pPager.memDb != 0
#endif
|| nMax < (int)pgno || noContent != 0 || !isOpen(pPager.fd) )
{
if ( pgno > pPager.mxPgno )
{
rc = SQLITE_FULL;
goto pager_acquire_err;
}
if ( noContent != 0 )
{
/* Failure to set the bits in the InJournal bit-vectors is benign.
** It merely means that we might do some extra work to journal a
** page that does not need to be journaled. Nevertheless, be sure
** to test the case where a malloc error occurs while trying to set
** a bit in a bit vector.
*/
sqlite3BeginBenignMalloc();
if ( pgno <= pPager.dbOrigSize )
{
#if !NDEBUG || SQLITE_COVERAGE_TEST
rc = sqlite3BitvecSet( pPager.pInJournal, pgno ); //TESTONLY( rc = ) sqlite3BitvecSet(pPager.pInJournal, pgno);
#else
sqlite3BitvecSet(pPager.pInJournal, pgno);
#endif
testcase( rc == SQLITE_NOMEM );
}
#if !NDEBUG || SQLITE_COVERAGE_TEST
rc = addToSavepointBitvecs( pPager, pgno ); //TESTONLY( rc = ) addToSavepointBitvecs(pPager, pgno);
#else
addToSavepointBitvecs(pPager, pgno);
#endif
testcase( rc == SQLITE_NOMEM );
sqlite3EndBenignMalloc();
}
//memset(pPg->pData, 0, pPager.pageSize);
Array.Clear( pPg.pData, 0, pPager.pageSize );
IOTRACE( "ZERO %p %d\n", pPager, pgno );
}
else
{
Debug.Assert( pPg.pPager == pPager );
rc = readDbPage( pPg );
if ( rc != SQLITE_OK )
{
goto pager_acquire_err;
}
}
#if SQLITE_CHECK_PAGES
pPg.pageHash = pager_pagehash(pPg);
#endif
}
return SQLITE_OK;
pager_acquire_err:
Debug.Assert( rc != SQLITE_OK );
if ( pPg != null )
{
sqlite3PcacheDrop( pPg );
}
pagerUnlockIfUnused( pPager );
ppPage = null;
return rc;
}
/*
** Acquire a reference to page number pgno in pager pPager (a page
** reference has type DbPage*). If the requested reference is
** successfully obtained, it is copied to *ppPage and SQLITE_OK returned.
**
** If the requested page is already in the cache, it is returned.
** Otherwise, a new page object is allocated and populated with data
** read from the database file. In some cases, the pcache module may
** choose not to allocate a new page object and may reuse an existing
** object with no outstanding references.
**
** The extra data appended to a page is always initialized to zeros the
** first time a page is loaded into memory. If the page requested is
** already in the cache when this function is called, then the extra
** data is left as it was when the page object was last used.
**
** If the database image is smaller than the requested page or if a
** non-zero value is passed as the noContent parameter and the
** requested page is not already stored in the cache, then no
** actual disk read occurs. In this case the memory image of the
** page is initialized to all zeros.
**
** If noContent is true, it means that we do not care about the contents
** of the page. This occurs in two seperate scenarios:
**
** a) When reading a free-list leaf page from the database, and
**
** b) When a savepoint is being rolled back and we need to load
** a new page into the cache to populate with the data read
** from the savepoint journal.
**
** If noContent is true, then the data returned is zeroed instead of
** being read from the database. Additionally, the bits corresponding
** to pgno in Pager.pInJournal (bitvec of pages already written to the
** journal file) and the PagerSavepoint.pInSavepoint bitvecs of any open
** savepoints are set. This means if the page is made writable at any
** point in the future, using a call to sqlite3PagerWrite(), its contents
** will not be journaled. This saves IO.
**
** The acquisition might fail for several reasons. In all cases,
** an appropriate error code is returned and *ppPage is set to NULL.
**
** See also sqlite3PagerLookup(). Both this routine and Lookup() attempt
** to find a page in the in-memory cache first. If the page is not already
** in memory, this routine goes to disk to read it in whereas Lookup()
** just returns 0. This routine acquires a read-lock the first time it
** has to go to disk, and could also playback an old journal if necessary.
** Since Lookup() never goes to disk, it never has to deal with locks
** or journal files.
*/
// Under C# from the header file
//#define sqlite3PagerGet(A,B,C) sqlite3PagerAcquire(A,B,C,0)
static int sqlite3PagerGet(
Pager pPager, /* The pager open on the database file */
u32 pgno, /* Page number to fetch */
ref DbPage ppPage /* Write a pointer to the page here */
)
{
return sqlite3PagerAcquire( pPager, pgno, ref ppPage, 0 );
}
/*
** Increment the reference count for page pPg.
*/
static void sqlite3PagerRef( DbPage pPg )
{
sqlite3PcacheRef( pPg );
}
/*
** Dummy page reinitializer
*/
static void pager_test_reiniter( DbPage pNotUsed )
{
return;
}
/*
** Return TRUE if the page given in the argument was previously passed
** to sqlite3PagerWrite(). In other words, return TRUE if it is ok
** to change the content of the page.
*/
#if !NDEBUG
static bool sqlite3PagerIswriteable( DbPage pPg )
{
return ( pPg.flags & PGHDR_DIRTY ) != 0;
}
/*
** Dummy page reinitializer
*/
static void pager_test_reiniter(DbPage pNotUsed)
{
return;
}
static bool sqlite3PagerIswriteable( DbPage pPg ) { return true; }
/*
** Copy nPage pages from the source b-tree to the destination.
*/
public static int sqlite3_backup_step(sqlite3_backup p, int nPage)
{
int rc;
sqlite3_mutex_enter(p.pSrcDb.mutex);
sqlite3BtreeEnter(p.pSrc);
if (p.pDestDb != null)
{
sqlite3_mutex_enter(p.pDestDb.mutex);
}
rc = p.rc;
if (!isFatalError(rc))
{
var pSrcPager = sqlite3BtreePager(p.pSrc); /* Source pager */
var pDestPager = sqlite3BtreePager(p.pDest); /* Dest pager */
int ii; /* Iterator variable */
uint nSrcPage = 0; /* Size of source db in pages */
var bCloseTrans = 0; /* True if src db requires unlocking */
/* If the source pager is currently in a write-transaction, return
** SQLITE_BUSY immediately.
*/
if (p.pDestDb != null && p.pSrc.pBt.inTransaction == TRANS_WRITE)
{
rc = SQLITE_BUSY;
}
else
{
rc = SQLITE_OK;
}
/* Lock the destination database, if it is not locked already. */
if (SQLITE_OK == rc && p.bDestLocked == 0 &&
SQLITE_OK == (rc = sqlite3BtreeBeginTrans(p.pDest, 2))
)
{
p.bDestLocked = 1;
sqlite3BtreeGetMeta(p.pDest, BTREE_SCHEMA_VERSION, ref p.iDestSchema);
}
/* If there is no open read-transaction on the source database, open
** one now. If a transaction is opened here, then it will be closed
** before this function exits.
*/
if (rc == SQLITE_OK && !sqlite3BtreeIsInReadTrans(p.pSrc))
{
rc = sqlite3BtreeBeginTrans(p.pSrc, 0);
bCloseTrans = 1;
}
/* Now that there is a read-lock on the source database, query the
** source pager for the number of pages in the database.
*/
if (rc == SQLITE_OK)
{
rc = sqlite3PagerPagecount(pSrcPager, ref nSrcPage);
}
for (ii = 0; (nPage < 0 || ii < nPage) && p.iNext <= nSrcPage && 0 == rc; ii++)
{
var iSrcPg = p.iNext; /* Source page number */
if (iSrcPg != PENDING_BYTE_PAGE(p.pSrc.pBt))
{
DbPage pSrcPg = null; /* Source page object */
rc = sqlite3PagerGet(pSrcPager, iSrcPg, ref pSrcPg);
if (rc == SQLITE_OK)
{
rc = backupOnePage(p, iSrcPg, sqlite3PagerGetData(pSrcPg));
sqlite3PagerUnref(pSrcPg);
}
}
p.iNext++;
}
if (rc == SQLITE_OK)
{
p.nPagecount = nSrcPage;
p.nRemaining = nSrcPage + 1 - p.iNext;
if (p.iNext > nSrcPage)
{
rc = SQLITE_DONE;
}
else if (0 == p.isAttached)
{
attachBackupObject(p);
}
}
/* Update the schema version field in the destination database. This
** is to make sure that the schema-version really does change in
** the case where the source and destination databases have the
** same schema version.
*/
if (rc == SQLITE_DONE &&
(rc = sqlite3BtreeUpdateMeta(p.pDest, 1, p.iDestSchema + 1)) == SQLITE_OK
)
{
var nSrcPagesize = sqlite3BtreeGetPageSize(p.pSrc);
var nDestPagesize = sqlite3BtreeGetPageSize(p.pDest);
uint nDestTruncate;
if (p.pDestDb != null)
{
sqlite3ResetInternalSchema(p.pDestDb, 0);
}
/* Set nDestTruncate to the final number of pages in the destination
** database. The complication here is that the destination page
** size may be different to the source page size.
**
** If the source page size is smaller than the destination page size,
** round up. In this case the call to sqlite3OsTruncate() below will
** fix the size of the file. However it is important to call
** sqlite3PagerTruncateImage() here so that any pages in the
** destination file that lie beyond the nDestTruncate page mark are
** journalled by PagerCommitPhaseOne() before they are destroyed
** by the file truncation.
*/
if (nSrcPagesize < nDestPagesize)
{
var ratio = nDestPagesize / nSrcPagesize;
nDestTruncate = (uint)((nSrcPage + ratio - 1) / ratio);
if (nDestTruncate == (int)PENDING_BYTE_PAGE(p.pDest.pBt))
{
nDestTruncate--;
}
}
else
{
nDestTruncate = (uint)(nSrcPage * (nSrcPagesize / nDestPagesize));
}
sqlite3PagerTruncateImage(pDestPager, nDestTruncate);
if (nSrcPagesize < nDestPagesize)
{
/* If the source page-size is smaller than the destination page-size,
** two extra things may need to happen:
**
** * The destination may need to be truncated, and
**
** * Data stored on the pages immediately following the
** pending-byte page in the source database may need to be
** copied into the destination database.
*/
var iSize = (uint)nSrcPagesize * nSrcPage;
var pFile = sqlite3PagerFile(pDestPager);
Debug.Assert(pFile != null);
Debug.Assert(nDestTruncate * nDestPagesize >= iSize ||
nDestTruncate == (int)(PENDING_BYTE_PAGE(p.pDest.pBt) - 1) &&
iSize >= PENDING_BYTE && iSize <= PENDING_BYTE + nDestPagesize);
if (SQLITE_OK == (rc = sqlite3PagerCommitPhaseOne(pDestPager, null, true)) &&
SQLITE_OK == (rc = backupTruncateFile(pFile, (int)iSize)) &&
SQLITE_OK == (rc = sqlite3PagerSync(pDestPager))
)
{
long iOff;
long iEnd = MIN(PENDING_BYTE + nDestPagesize, iSize);
for (
iOff = PENDING_BYTE + nSrcPagesize;
rc == SQLITE_OK && iOff < iEnd;
iOff += nSrcPagesize
)
{
PgHdr pSrcPg = null;
var iSrcPg = (uint)(iOff / nSrcPagesize + 1);
rc = sqlite3PagerGet(pSrcPager, iSrcPg, ref pSrcPg);
if (rc == SQLITE_OK)
{
var zData = sqlite3PagerGetData(pSrcPg);
rc = sqlite3OsWrite(pFile, zData, nSrcPagesize, iOff);
}
sqlite3PagerUnref(pSrcPg);
}
}
}
else
{
rc = sqlite3PagerCommitPhaseOne(pDestPager, null, false);
}
/* Finish committing the transaction to the destination database. */
if (SQLITE_OK == rc &&
SQLITE_OK == (rc = sqlite3BtreeCommitPhaseTwo(p.pDest))
)
{
rc = SQLITE_DONE;
}
}
/* If bCloseTrans is true, then this function opened a read transaction
** on the source database. Close the read transaction here. There is
** no need to check the return values of the btree methods here, as
** "committing" a read-only transaction cannot fail.
*/
if (bCloseTrans != 0)
{
#if !NDEBUG || SQLITE_COVERAGE_TEST
//TESTONLY( int rc2 );
//TESTONLY( rc2 = ) sqlite3BtreeCommitPhaseOne(p.pSrc, 0);
//TESTONLY( rc2 |= ) sqlite3BtreeCommitPhaseTwo(p.pSrc);
int rc2;
rc2 = sqlite3BtreeCommitPhaseOne(p.pSrc, "");
rc2 |= sqlite3BtreeCommitPhaseTwo(p.pSrc);
Debug.Assert(rc2 == SQLITE_OK);
#else
sqlite3BtreeCommitPhaseOne(p.pSrc, null);
sqlite3BtreeCommitPhaseTwo(p.pSrc);
#endif
}
p.rc = rc;
}
if (p.pDestDb != null)
{
sqlite3_mutex_leave(p.pDestDb.mutex);
}
sqlite3BtreeLeave(p.pSrc);
sqlite3_mutex_leave(p.pSrcDb.mutex);
return(rc);
}
