internal RC ptrmapGet(Pgno key, ref PTRMAP pEType, ref Pgno pPgno)
{
Debug.Assert(MutexEx.Held(this.Mutex));
var iPtrmap = (int)MemPage.PTRMAP_PAGENO(this, key);
var pDbPage = new PgHdr(); // The pointer map page
var rc = this.Pager.Get((Pgno)iPtrmap, ref pDbPage);
if (rc != RC.OK)
{
return(rc);
}
var pPtrmap = Pager.sqlite3PagerGetData(pDbPage);// Pointer map page data
var offset = (int)MemPage.PTRMAP_PTROFFSET((Pgno)iPtrmap, key);
if (offset < 0)
{
Pager.Unref(pDbPage);
return(SysEx.SQLITE_CORRUPT_BKPT());
}
Debug.Assert(offset <= (int)this.UsableSize - 5);
var v = pPtrmap[offset];
if (v < 1 || v > 5)
{
return(SysEx.SQLITE_CORRUPT_BKPT());
}
pEType = (PTRMAP)v;
pPgno = ConvertEx.Get4(pPtrmap, offset + 1);
Pager.Unref(pDbPage);
return(RC.OK);
}
internal void ptrmapPut(Pgno key, PTRMAP eType, Pgno parent, ref RC rRC)
{
if (rRC != RC.OK)
{
return;
}
Debug.Assert(MutexEx.Held(this.Mutex));
// The master-journal page number must never be used as a pointer map page
Debug.Assert(!MemPage.PTRMAP_ISPAGE(this, MemPage.PENDING_BYTE_PAGE(this)));
Debug.Assert(this.AutoVacuum);
if (key == 0)
{
rRC = SysEx.SQLITE_CORRUPT_BKPT();
return;
}
var iPtrmap = MemPage.PTRMAP_PAGENO(this, key);
var pDbPage = new PgHdr(); // The pointer map page
var rc = this.Pager.Get(iPtrmap, ref pDbPage);
if (rc != RC.OK)
{
rRC = rc;
return;
}
var offset = (int)MemPage.PTRMAP_PTROFFSET(iPtrmap, key);
if (offset < 0)
{
rRC = SysEx.SQLITE_CORRUPT_BKPT();
goto ptrmap_exit;
}
Debug.Assert(offset <= (int)this.UsableSize - 5);
var pPtrmap = Pager.sqlite3PagerGetData(pDbPage); // The pointer map data
if (eType != (PTRMAP)pPtrmap[offset] || ConvertEx.Get4(pPtrmap, offset + 1) != parent)
{
Btree.TRACE("PTRMAP_UPDATE: {0}->({1},{2})", key, eType, parent);
rRC = rc = Pager.Write(pDbPage);
if (rc == RC.OK)
{
pPtrmap[offset] = (byte)eType;
ConvertEx.Put4L(pPtrmap, (uint)offset + 1, parent);
}
}
ptrmap_exit:
Pager.Unref(pDbPage);
}
internal RC btreeCreateTable(ref int piTable, CREATETABLE createTabFlags)
{
var pBt = this.Shared;
var pRoot = new MemPage();
Pgno pgnoRoot = 0;
int ptfFlags; // Page-type flage for the root page of new table
RC rc;
Debug.Assert(sqlite3BtreeHoldsMutex());
Debug.Assert(pBt.InTransaction == TRANS.WRITE);
Debug.Assert(!pBt.ReadOnly);
#if SQLITE_OMIT_AUTOVACUUM
rc = allocateBtreePage(pBt, ref pRoot, ref pgnoRoot, 1, 0);
if (rc != SQLITE.OK)
{
return(rc);
}
#else
if (pBt.AutoVacuum)
{
Pgno pgnoMove = 0; // Move a page here to make room for the root-page
var pPageMove = new MemPage(); // The page to move to.
// Creating a new table may probably require moving an existing database to make room for the new tables root page. In case this page turns
// out to be an overflow page, delete all overflow page-map caches held by open cursors.
invalidateAllOverflowCache(pBt);
// Read the value of meta[3] from the database to determine where the root page of the new table should go. meta[3] is the largest root-page
// created so far, so the new root-page is (meta[3]+1).
GetMeta((int)META.LARGEST_ROOT_PAGE, ref pgnoRoot);
pgnoRoot++;
// The new root-page may not be allocated on a pointer-map page, or the PENDING_BYTE page.
while (pgnoRoot == MemPage.PTRMAP_PAGENO(pBt, pgnoRoot) || pgnoRoot == MemPage.PENDING_BYTE_PAGE(pBt))
{
pgnoRoot++;
}
Debug.Assert(pgnoRoot >= 3);
// Allocate a page. The page that currently resides at pgnoRoot will be moved to the allocated page (unless the allocated page happens to reside at pgnoRoot).
rc = pBt.allocateBtreePage(ref pPageMove, ref pgnoMove, pgnoRoot, 1);
if (rc != RC.OK)
{
return(rc);
}
if (pgnoMove != pgnoRoot)
{
// pgnoRoot is the page that will be used for the root-page of the new table (assuming an error did not occur). But we were
// allocated pgnoMove. If required (i.e. if it was not allocated by extending the file), the current page at position pgnoMove
// is already journaled.
PTRMAP eType = 0;
Pgno iPtrPage = 0;
pPageMove.releasePage();
// Move the page currently at pgnoRoot to pgnoMove.
rc = pBt.btreeGetPage(pgnoRoot, ref pRoot, 0);
if (rc != RC.OK)
{
return(rc);
}
rc = pBt.ptrmapGet(pgnoRoot, ref eType, ref iPtrPage);
if (eType == PTRMAP.ROOTPAGE || eType == PTRMAP.FREEPAGE)
{
rc = SysEx.SQLITE_CORRUPT_BKPT();
}
if (rc != RC.OK)
{
pRoot.releasePage();
return(rc);
}
Debug.Assert(eType != PTRMAP.ROOTPAGE);
Debug.Assert(eType != PTRMAP.FREEPAGE);
rc = MemPage.relocatePage(pBt, pRoot, eType, iPtrPage, pgnoMove, 0);
pRoot.releasePage();
// Obtain the page at pgnoRoot
if (rc != RC.OK)
{
return(rc);
}
rc = pBt.btreeGetPage(pgnoRoot, ref pRoot, 0);
if (rc != RC.OK)
{
return(rc);
}
rc = Pager.Write(pRoot.DbPage);
if (rc != RC.OK)
{
pRoot.releasePage();
return(rc);
}
}
else
{
pRoot = pPageMove;
}
// Update the pointer-map and meta-data with the new root-page number.
pBt.ptrmapPut(pgnoRoot, PTRMAP.ROOTPAGE, 0, ref rc);
if (rc != RC.OK)
{
pRoot.releasePage();
return(rc);
}
// When the new root page was allocated, page 1 was made writable in order either to increase the database filesize, or to decrement the
// freelist count. Hence, the sqlite3BtreeUpdateMeta() call cannot fail.
Debug.Assert(Pager.IsPageWriteable(pBt.Page1.DbPage));
rc = SetMeta(4, pgnoRoot);
if (Check.NEVER(rc != RC.OK))
{
pRoot.releasePage();
return(rc);
}
}
else
{
rc = pBt.allocateBtreePage(ref pRoot, ref pgnoRoot, 1, 0);
if (rc != RC.OK)
{
return(rc);
}
}
#endif
Debug.Assert(Pager.IsPageWriteable(pRoot.DbPage));
ptfFlags = ((createTabFlags & CREATETABLE.INTKEY) != 0 ? PTF_INTKEY | PTF_LEAFDATA | PTF_LEAF : PTF_ZERODATA | PTF_LEAF);
pRoot.zeroPage(ptfFlags);
Pager.Unref(pRoot.DbPage);
Debug.Assert((pBt.OpenFlags & OPEN.SINGLE) == 0 || pgnoRoot == 2);
piTable = (int)pgnoRoot;
return(RC.OK);
}
