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);
}
