/// <summary>
/// Creates a new tree node in storage.
/// </summary>
/// <param name="isLeaf">Value indicating whether a created node is leaf node</param>
/// <returns>Created node</returns>
public IBPlusTreeNode <TKey> Create(bool isLeaf)
{
IPage p = _pageManager.CreatePage();
return(new BPlusTreeNode <TKey>(p.Index)
{
IsLeaf = isLeaf
});
}
private DbItemReference AllocateSinglePage(DbItem item)
{
DbItemReference result;
IPage page;
var fsmValue = EnumHelper.FsmValueFromSizeRange(item.SizeRange);
var index = _fsm.GetFreePageIndex(fsmValue);
bool spaceRemains;
if (index != -1)
{
// place object to existing page
page = _pageManager.FetchPage(index);
result = PageFormatter.AddFixedSizeItem(page, item, out spaceRemains);
if (!spaceRemains)
{
_fsm.Set(index, FsmValue.Full);
}
}
else
{
// allocate on a new page
page = _pageManager.CreatePage();
var header = new FixedSizeItemsPageHeader {
SizeRange = item.SizeRange
};
PageFormatter.InitPage(page, header);
result = PageFormatter.AddFixedSizeItem(page, item, out spaceRemains);
_fsm.Set(result.PageIndex, spaceRemains ? fsmValue : FsmValue.Full);
}
_pageManager.UpdatePage(page);
return(result);
}
public IRadixTreeNode Create(int prefixSize, int childCapacity)
{
CheckRoot();
IPage page;
short itemIndex;
var node = NewNode(DbItemReference.Null);
foreach (var pageIndex in _recentPages)
{
page = _pageManager.FetchPage(pageIndex);
if (page.BackingObject == null)
{
var obj = RadixTreePageBackingObject.FromPage(page);
page = new Page(_pageManager, pageIndex, () => Serialize(obj), obj);
}
var backingObject = (RadixTreePageBackingObject)page.BackingObject;
itemIndex = AddNode(backingObject, node, prefixSize, childCapacity);
if (itemIndex != -1)
{
UpdateRecentPage(page.Index);
node.Reference = new DbItemReference(page.Index, itemIndex);
_pageManager.UpdatePage(page);
return(node);
}
}
page = _pageManager.CreatePage();
var obj1 = new RadixTreePageBackingObject(page.Index);
long index1 = page.Index;
page = new Page(_pageManager, index1, () => Serialize(obj1), obj1);
itemIndex = AddNode((RadixTreePageBackingObject)page.BackingObject, node, prefixSize, childCapacity);
if (itemIndex != -1)
{
UpdateRecentPage(page.Index);
node.Reference = new DbItemReference(page.Index, itemIndex);
_pageManager.UpdatePage(page);
return(node);
}
Debug.Fail("Should never get here");
return(null);
}
/// <summary>
/// Creates a new page in storage.
/// </summary>
/// <returns>Created page</returns>
public IPage CreatePage()
{
CheckDisposed();
Lock();
try
{
IPage page = _underlyingPageManager.CreatePage();
AddPage(page);
return(GetPage(page.Index));
}
finally
{
Unlock();
}
}
public void Set(long pageIndex, FsmValue value)
{
if (!_isInitialized)
{
Init();
}
IPage page = GetFsmPageByTargetPageIndex(pageIndex);
if (page == null)
{
// fsm-page is missing for requested page index
long previousPageIndex = _lastFsmPage.Index;
var missingPageCount = (int)((pageIndex - (_fsmPageCount - _fsmPageIndexes.Count) * _entryPerPage) / _entryPerPage + 1);
var pages = new List <IPage>(missingPageCount);
// allocate new pages
for (int i = 0; i < missingPageCount; i++)
{
pages.Add(_pageManager.CreatePage());
}
var baseIndex = PageFormatter.GetBasePageIndex(_lastFsmPage);
// initialize them
for (int i = 0; i < missingPageCount; i++)
{
baseIndex += _entryPerPage;
InitFsmPage(pages[i],
previousPageIndex,
i == missingPageCount - 1 ? -1 : pages[i + 1].Index,
baseIndex);
previousPageIndex = pages[i].Index;
}
// and update
pages.ForEach(_pageManager.UpdatePage);
// save reference to added pages
var lastPageHeader = (FreeSpaceMapPageHeader)PageFormatter.GetPageHeader(_lastFsmPage);
lastPageHeader.NextPageIndex = pages[0].Index;
lastPageHeader.WriteToPage(_lastFsmPage);
_pageManager.UpdatePage(_lastFsmPage);
_lastFsmPage = null;
_fsmPageCount = -1;
Set(pageIndex, value);
}
else
{
PageFormatter.SetFsmValue(page, (int)pageIndex % _entryPerPage, value);
_pageManager.UpdatePage(page);
var fsmValuesToUpdate = _luckyFsmPages.Where(item => item.Value.Page.Index == page.Index).Select(item => item.Key).ToList();
foreach (var fsmValue in fsmValuesToUpdate)
{
_luckyFsmPages[fsmValue].Page = page;
}
if (!_luckyFsmPages.ContainsKey(value))
{
_luckyFsmPages[value] = new LuckyPage {
Page = page, LastGoodIndex = pageIndex
}
}
;
else
{
if (_scanned.Contains(value))
{
_scanned.Remove(value);
}
}
}
}