// was:sqlite3PagerOpenSavepoint
public RC OpenSavepoint(int nSavepoint)
{
var rc = RC.OK;
var nCurrent = this.nSavepoint; // Current number of savepoints
Debug.Assert(this.eState >= PAGER.WRITER_LOCKED);
Debug.Assert(assert_pager_state());
if (nSavepoint > nCurrent && this.useJournal != 0)
{
// Grow the Pager.aSavepoint array using realloc(). Return SQLITE_NOMEM if the allocation fails. Otherwise, zero the new portion in case a
// malloc failure occurs while populating it in the for(...) loop below.
Array.Resize(ref this.aSavepoint, nSavepoint);
var aNew = this.aSavepoint; // New Pager.aSavepoint array
// Populate the PagerSavepoint structures just allocated.
for (var ii = nCurrent; ii < nSavepoint; ii++)
{
aNew[ii] = new PagerSavepoint();
aNew[ii].nOrig = this.dbSize;
aNew[ii].iOffset = (this.jfd.IsOpen && this.journalOff > 0 ? this.journalOff : (int)JOURNAL_HDR_SZ(this));
aNew[ii].iSubRec = this.nSubRec;
aNew[ii].pInSavepoint = new BitArray(this.dbSize);
if (pagerUseWal())
this.pWal.Savepoint(aNew[ii].aWalData);
this.nSavepoint = ii + 1;
}
Debug.Assert(this.nSavepoint == nSavepoint);
assertTruncateConstraint();
}
return rc;
}
// was:sqlite3PagerOpenSavepoint
public RC OpenSavepoint(int nSavepoint)
{
var rc = RC.OK;
var nCurrent = this.nSavepoint; // Current number of savepoints
Debug.Assert(this.eState >= PAGER.WRITER_LOCKED);
Debug.Assert(assert_pager_state());
if (nSavepoint > nCurrent && this.useJournal != 0)
{
// Grow the Pager.aSavepoint array using realloc(). Return SQLITE_NOMEM if the allocation fails. Otherwise, zero the new portion in case a
// malloc failure occurs while populating it in the for(...) loop below.
Array.Resize(ref this.aSavepoint, nSavepoint);
var aNew = this.aSavepoint; // New Pager.aSavepoint array
// Populate the PagerSavepoint structures just allocated.
for (var ii = nCurrent; ii < nSavepoint; ii++)
{
aNew[ii] = new PagerSavepoint();
aNew[ii].nOrig = this.dbSize;
aNew[ii].iOffset = (this.jfd.IsOpen && this.journalOff > 0 ? this.journalOff : (int)JOURNAL_HDR_SZ(this));
aNew[ii].iSubRec = this.nSubRec;
aNew[ii].pInSavepoint = new BitArray(this.dbSize);
if (pagerUseWal())
{
this.pWal.Savepoint(aNew[ii].aWalData);
}
this.nSavepoint = ii + 1;
}
Debug.Assert(this.nSavepoint == nSavepoint);
assertTruncateConstraint();
}
return(rc);
}
private RC pagerPlaybackSavepoint(PagerSavepoint pSavepoint)
{
Debug.Assert(this.eState != PAGER.ERROR);
Debug.Assert(this.eState >= PAGER.WRITER_LOCKED);
// Allocate a bitvec to use to store the set of pages rolled back
BitArray pDone = null; // Bitvec to ensure pages played back only once
if (pSavepoint != null)
{
pDone = new BitArray(pSavepoint.nOrig);
}
// Set the database size back to the value it was before the savepoint being reverted was opened.
this.dbSize = pSavepoint != null ? pSavepoint.nOrig : this.dbOrigSize;
this.changeCountDone = this.tempFile;
if (!pSavepoint && this.pagerUseWal())
{
return(this.pagerRollbackWal());
}
// Use pPager.journalOff as the effective size of the main rollback journal. The actual file might be larger than this in
// PAGER_JOURNALMODE_TRUNCATE or PAGER_JOURNALMODE_PERSIST. But anything past pPager.journalOff is off-limits to us.
var szJ = this.journalOff; // Effective size of the main journal
Debug.Assert(!this.pagerUseWal() || szJ == 0);
// Begin by rolling back records from the main journal starting at PagerSavepoint.iOffset and continuing to the next journal header.
// There might be records in the main journal that have a page number greater than the current database size (pPager.dbSize) but those
// will be skipped automatically. Pages are added to pDone as they are played back.
long iHdrOff; // End of first segment of main-journal records
var rc = RC.OK; // Return code
if (pSavepoint != null && !this.pagerUseWal())
{
iHdrOff = (pSavepoint.iHdrOffset != 0 ? pSavepoint.iHdrOffset : szJ);
this.journalOff = pSavepoint.iOffset;
while (rc == RC.OK && this.journalOff < iHdrOff)
{
rc = pager_playback_one_page(ref this.journalOff, pDone, 1, 1);
}
Debug.Assert(rc != RC.DONE);
}
else
{
this.journalOff = 0;
}
// Continue rolling back records out of the main journal starting at the first journal header seen and continuing until the effective end
// of the main journal file. Continue to skip out-of-range pages and continue adding pages rolled back to pDone.
while (rc == RC.OK && this.journalOff < szJ)
{
uint nJRec; // Number of Journal Records
uint dummy;
rc = readJournalHdr(0, szJ, out nJRec, out dummy);
Debug.Assert(rc != RC.DONE);
// The "pPager.journalHdr+JOURNAL_HDR_SZ(pPager)==pPager.journalOff" test is related to ticket #2565. See the discussion in the
// pager_playback() function for additional information.
if (nJRec == 0 && this.journalHdr + JOURNAL_HDR_SZ(this) >= this.journalOff)
{
nJRec = (uint)((szJ - this.journalOff) / JOURNAL_PG_SZ(this));
}
for (uint ii = 0; rc == RC.OK && ii < nJRec && this.journalOff < szJ; ii++)
{
rc = pager_playback_one_page(ref this.journalOff, pDone, 1, 1);
}
Debug.Assert(rc != RC.DONE);
}
Debug.Assert(rc != RC.OK || this.journalOff >= szJ);
// Finally, rollback pages from the sub-journal. Page that were previously rolled back out of the main journal (and are hence in pDone)
// will be skipped. Out-of-range pages are also skipped.
if (pSavepoint != null)
{
long offset = pSavepoint.iSubRec * (4 + this.pageSize);
if (this.pagerUseWal())
{
rc = this.pWal.SavepointUndo(pSavepoint.aWalData);
}
for (var ii = pSavepoint.iSubRec; rc == RC.OK && ii < this.nSubRec; ii++)
{
Debug.Assert(offset == ii * (4 + this.pageSize));
rc = pager_playback_one_page(ref offset, pDone, 0, 1);
}
Debug.Assert(rc != RC.DONE);
}
BitArray.Destroy(ref pDone);
if (rc == RC.OK)
{
this.journalOff = (int)szJ;
}
return(rc);
}
private RC pagerPlaybackSavepoint(PagerSavepoint pSavepoint)
{
Debug.Assert(this.eState != PAGER.ERROR);
Debug.Assert(this.eState >= PAGER.WRITER_LOCKED);
// Allocate a bitvec to use to store the set of pages rolled back
BitArray pDone = null; // Bitvec to ensure pages played back only once
if (pSavepoint != null)
pDone = new BitArray(pSavepoint.nOrig);
// Set the database size back to the value it was before the savepoint being reverted was opened.
this.dbSize = pSavepoint != null ? pSavepoint.nOrig : this.dbOrigSize;
this.changeCountDone = this.tempFile;
if (!pSavepoint && this.pagerUseWal())
return this.pagerRollbackWal();
// Use pPager.journalOff as the effective size of the main rollback journal. The actual file might be larger than this in
// PAGER_JOURNALMODE_TRUNCATE or PAGER_JOURNALMODE_PERSIST. But anything past pPager.journalOff is off-limits to us.
var szJ = this.journalOff; // Effective size of the main journal
Debug.Assert(!this.pagerUseWal() || szJ == 0);
// Begin by rolling back records from the main journal starting at PagerSavepoint.iOffset and continuing to the next journal header.
// There might be records in the main journal that have a page number greater than the current database size (pPager.dbSize) but those
// will be skipped automatically. Pages are added to pDone as they are played back.
long iHdrOff; // End of first segment of main-journal records
var rc = RC.OK; // Return code
if (pSavepoint != null && !this.pagerUseWal())
{
iHdrOff = (pSavepoint.iHdrOffset != 0 ? pSavepoint.iHdrOffset : szJ);
this.journalOff = pSavepoint.iOffset;
while (rc == RC.OK && this.journalOff < iHdrOff)
rc = pager_playback_one_page(ref this.journalOff, pDone, 1, 1);
Debug.Assert(rc != RC.DONE);
}
else
this.journalOff = 0;
// Continue rolling back records out of the main journal starting at the first journal header seen and continuing until the effective end
// of the main journal file. Continue to skip out-of-range pages and continue adding pages rolled back to pDone.
while (rc == RC.OK && this.journalOff < szJ)
{
uint nJRec; // Number of Journal Records
uint dummy;
rc = readJournalHdr(0, szJ, out nJRec, out dummy);
Debug.Assert(rc != RC.DONE);
// The "pPager.journalHdr+JOURNAL_HDR_SZ(pPager)==pPager.journalOff" test is related to ticket #2565. See the discussion in the
// pager_playback() function for additional information.
if (nJRec == 0 && this.journalHdr + JOURNAL_HDR_SZ(this) >= this.journalOff)
nJRec = (uint)((szJ - this.journalOff) / JOURNAL_PG_SZ(this));
for (uint ii = 0; rc == RC.OK && ii < nJRec && this.journalOff < szJ; ii++)
rc = pager_playback_one_page(ref this.journalOff, pDone, 1, 1);
Debug.Assert(rc != RC.DONE);
}
Debug.Assert(rc != RC.OK || this.journalOff >= szJ);
// Finally, rollback pages from the sub-journal. Page that were previously rolled back out of the main journal (and are hence in pDone)
// will be skipped. Out-of-range pages are also skipped.
if (pSavepoint != null)
{
long offset = pSavepoint.iSubRec * (4 + this.pageSize);
if (this.pagerUseWal())
rc = this.pWal.SavepointUndo(pSavepoint.aWalData);
for (var ii = pSavepoint.iSubRec; rc == RC.OK && ii < this.nSubRec; ii++)
{
Debug.Assert(offset == ii * (4 + this.pageSize));
rc = pager_playback_one_page(ref offset, pDone, 0, 1);
}
Debug.Assert(rc != RC.DONE);
}
BitArray.Destroy(ref pDone);
if (rc == RC.OK)
this.journalOff = (int)szJ;
return rc;
}
