public byte *AddSeparator(Slice separator, long pageRefNumber, int?nodePos = null)
{
var originalLastSearchPositionOfParent = _parentPage.LastSearchPosition;
if (nodePos == null)
{
nodePos = _parentPage.NodePositionFor(_tx, separator); // select the appropriate place for this
}
if (_parentPage.HasSpaceFor(_tx, TreeSizeOf.BranchEntry(separator) + Constants.NodeOffsetSize) == false)
{
var pageSplitter = new TreePageSplitter(_tx, _tree, separator, -1, pageRefNumber, TreeNodeFlags.PageRef, 0, _cursor);
var posToInsert = pageSplitter.Execute();
ParentOfAddedPageRef = _cursor.CurrentPage;
var adjustParentPageOnCursor = true;
for (int i = 0; i < _cursor.CurrentPage.NumberOfEntries; i++)
{
if (_cursor.CurrentPage.GetNode(i)->PageNumber == _currentPage.PageNumber)
{
adjustParentPageOnCursor = false;
_cursor.CurrentPage.LastSearchPosition = i;
break;
}
}
if (adjustParentPageOnCursor)
{
// the above page split has modified the cursor that its first page points to the parent of the leaf where 'separatorKey' was inserted
// and it doesn't have the reference to _page, we need to ensure that the actual parent is first at the cursor
_cursor.Pop();
_cursor.Push(_parentPage);
EnsureValidLastSearchPosition(_parentPage, _currentPage.PageNumber, originalLastSearchPositionOfParent);
}
#if VALIDATE
Debug.Assert(_cursor.CurrentPage.GetNode(_cursor.CurrentPage.LastSearchPosition)->PageNumber == _currentPage.PageNumber,
"The parent page is not referencing a page which is being split");
var parentToValidate = ParentOfAddedPageRef;
Debug.Assert(Enumerable.Range(0, parentToValidate.NumberOfEntries).Any(i => parentToValidate.GetNode(i)->PageNumber == pageRefNumber),
"The parent page of a page reference isn't referencing it");
#endif
return(posToInsert);
}
ParentOfAddedPageRef = _parentPage;
var pos = _parentPage.AddPageRefNode(nodePos.Value, separator, pageRefNumber);
EnsureValidLastSearchPosition(_parentPage, _currentPage.PageNumber, originalLastSearchPositionOfParent);
return(pos);
}
private void DeleteOnCompressedPage(TreePage page, Slice keyToDelete, ref TreeCursorConstructor cursorConstructor)
{
var tombstoneNodeSize = page.GetRequiredSpace(keyToDelete, 0);
page = ModifyPage(page);
if (page.HasSpaceFor(_llt, tombstoneNodeSize))
{
if (page.LastMatch == 0)
{
RemoveLeafNode(page);
}
page.AddCompressionTombstoneNode(page.LastSearchPosition, keyToDelete);
return;
}
var decompressed = DecompressPage(page, usage: DecompressionUsage.Write);
try
{
decompressed.Search(_llt, keyToDelete);
if (decompressed.LastMatch != 0)
{
return;
}
State.NumberOfEntries--;
RemoveLeafNode(decompressed);
using (var cursor = cursorConstructor.Build(keyToDelete))
{
var treeRebalancer = new TreeRebalancer(_llt, this, cursor);
var changedPage = (TreePage)decompressed;
while (changedPage != null)
{
changedPage = treeRebalancer.Execute(changedPage);
}
}
page.DebugValidate(this, State.RootPageNumber);
}
finally
{
decompressed.CopyToOriginal(_llt, defragRequired: true, wasModified: true, this);
}
}
private byte *InsertNewKey(TreePage p)
{
int pos = p.NodePositionFor(_tx, _newKey);
var newKeyToInsert = _newKey;
if (p.HasSpaceFor(_tx, p.GetRequiredSpace(newKeyToInsert, _len)) == false)
{
_cursor.Push(p);
var pageSplitter = new TreePageSplitter(_tx, _tree, _newKey, _len, _pageNumber, _nodeType, _cursor);
return(pageSplitter.Execute());
}
byte *dataPos = AddNodeToPage(p, pos, newKeyToInsert);
_cursor.Push(p);
return(dataPos);
}
public void MultiAdd(Slice key, Slice value)
{
if (!value.HasValue)
{
throw new ArgumentNullException(nameof(value));
}
int maxNodeSize = Llt.DataPager.NodeMaxSize;
if (value.Size > maxNodeSize)
{
throw new ArgumentException("Cannot add a value to child tree that is over " + maxNodeSize + " bytes in size", nameof(value));
}
if (value.Size == 0)
{
throw new ArgumentException("Cannot add empty value to child tree");
}
State.IsModified = true;
State.Flags |= TreeFlags.MultiValueTrees;
TreeNodeHeader *node;
var page = FindPageFor(key, out node);
if (page == null || page.LastMatch != 0)
{
MultiAddOnNewValue(key, value, maxNodeSize);
return;
}
page = ModifyPage(page);
var item = page.GetNode(page.LastSearchPosition);
byte *_;
// already was turned into a multi tree, not much to do here
if (item->Flags == TreeNodeFlags.MultiValuePageRef)
{
var existingTree = OpenMultiValueTree(key, item);
existingTree.DirectAdd(value, 0, out _).Dispose();
return;
}
if (item->Flags == TreeNodeFlags.PageRef)
{
throw new InvalidOperationException("Multi trees don't use overflows");
}
var nestedPagePtr = DirectAccessFromHeader(item);
var nestedPage = new TreePage(nestedPagePtr, (ushort)GetDataSize(item));
var existingItem = nestedPage.Search(_llt, value);
if (nestedPage.LastMatch != 0)
{
existingItem = null;// not an actual match, just greater than
}
if (existingItem != null)
{
// maybe same value added twice?
Slice tmpKey;
using (TreeNodeHeader.ToSlicePtr(_llt.Allocator, item, out tmpKey))
{
if (SliceComparer.Equals(tmpKey, value))
{
return; // already there, turning into a no-op
}
}
nestedPage.RemoveNode(nestedPage.LastSearchPosition);
}
if (nestedPage.HasSpaceFor(_llt, value, 0))
{
// we are now working on top of the modified root page, we can just modify the memory directly
nestedPage.AddDataNode(nestedPage.LastSearchPosition, value, 0);
return;
}
if (page.HasSpaceFor(_llt, value, 0))
{
// page has space for an additional node in nested page ...
var requiredSpace = nestedPage.PageSize + // existing page
nestedPage.GetRequiredSpace(value, 0); // new node
if (requiredSpace + Constants.Tree.NodeHeaderSize <= maxNodeSize)
{
// ... and it won't require to create an overflow, so we can just expand the current value, no need to create a nested tree yet
EnsureNestedPagePointer(page, item, ref nestedPage, ref nestedPagePtr);
var newPageSize = (ushort)Math.Min(Bits.NextPowerOf2(requiredSpace), maxNodeSize - Constants.Tree.NodeHeaderSize);
ExpandMultiTreeNestedPageSize(key, value, nestedPagePtr, newPageSize, nestedPage.PageSize);
return;
}
}
EnsureNestedPagePointer(page, item, ref nestedPage, ref nestedPagePtr);
// we now have to convert this into a tree instance, instead of just a nested page
var tree = Create(_llt, _tx, key, TreeFlags.MultiValue);
for (int i = 0; i < nestedPage.NumberOfEntries; i++)
{
Slice existingValue;
using (nestedPage.GetNodeKey(_llt, i, out existingValue))
{
tree.DirectAdd(existingValue, 0, out _).Dispose();
}
}
tree.DirectAdd(value, 0, out _).Dispose();
_tx.AddMultiValueTree(this, key, tree);
// we need to record that we switched to tree mode here, so the next call wouldn't also try to create the tree again
DirectAdd(key, sizeof(TreeRootHeader), TreeNodeFlags.MultiValuePageRef, out _).Dispose();
}
