public SlotStream(LocalHeap heap, ExternalFileListSlot slot, long offset, H5DatasetAccess datasetAccess)
{
_heap = heap;
_slot = slot;
this.Offset = offset;
_datasetAccess = datasetAccess;
}
private bool TryGetReference(string name, H5LinkAccess linkAccess, out H5NamedReference namedReference)
{
namedReference = default;
/* cached data */
if (_scratchPad != null)
{
var localHeap = _scratchPad.LocalHeap;
this.Context.Reader.Seek((long)_scratchPad.BTree1Address, SeekOrigin.Begin);
var tree = new BTree1Node <BTree1GroupKey>(this.Context.Reader, this.Context.Superblock, this.DecodeGroupKey);
var b = tree.EnumerateNodes().ToList();
this.Context.Reader.Seek((long)_scratchPad.NameHeapAddress, SeekOrigin.Begin);
var heap = new LocalHeap(this.Context.Reader, this.Context.Superblock);
var c = heap.GetObjectName(0);
var success = _scratchPad
.GetBTree1(this.DecodeGroupKey)
.TryFindUserData(out var userData,
(leftKey, rightKey) => this.NodeCompare3(localHeap, name, leftKey, rightKey),
(ulong address, out BTree1SymbolTableUserData userData) => this.NodeFound(localHeap, name, address, out userData));
if (success)
{
namedReference = this.GetObjectReferencesForSymbolTableEntry(localHeap, userData.SymbolTableEntry, linkAccess);
return(true);
}
}
else
{
var symbolTableHeaderMessages = this.Header.GetMessages <SymbolTableMessage>();
if (symbolTableHeaderMessages.Any())
{
/* Original approach.
* IV.A.2.r.: The Symbol Table Message
* Required for "old style" groups; may not be repeated. */
if (symbolTableHeaderMessages.Count() != 1)
{
throw new Exception("There may be only a single symbol table header message.");
}
var smessage = symbolTableHeaderMessages.First();
var localHeap = smessage.LocalHeap;
var success = smessage
.GetBTree1(this.DecodeGroupKey)
.TryFindUserData(out var userData,
(leftKey, rightKey) => this.NodeCompare3(localHeap, name, leftKey, rightKey),
(ulong address, out BTree1SymbolTableUserData userData) => this.NodeFound(localHeap, name, address, out userData));
if (success)
{
namedReference = this.GetObjectReferencesForSymbolTableEntry(localHeap, userData.SymbolTableEntry, linkAccess);
return(true);
}
}
else
{
var linkInfoMessages = this.Header.GetMessages <LinkInfoMessage>();
if (linkInfoMessages.Any())
{
if (linkInfoMessages.Count() != 1)
{
throw new Exception("There may be only a single link info message.");
}
var lmessage = linkInfoMessages.First();
/* New (1.8) indexed format (in combination with Group Info Message)
* IV.A.2.c. The Link Info Message
* Optional; may not be repeated. */
if (!this.Context.Superblock.IsUndefinedAddress(lmessage.BTree2NameIndexAddress))
{
if (this.TryGetLinkMessageFromLinkInfoMessage(lmessage, name, out var linkMessage))
{
namedReference = this.GetObjectReference(linkMessage, linkAccess);
return(true);
}
}
/* New (1.8) compact format
* IV.A.2.g. The Link Message
* A group is storing its links compactly when the fractal heap address
* in the Link Info Message is set to the "undefined address" value. */
else
{
var linkMessage = this.Header
.GetMessages <LinkMessage>()
.FirstOrDefault(message => message.LinkName == name);
if (linkMessage != null)
{
namedReference = this.GetObjectReference(linkMessage, linkAccess);
return(true);
}
}
}
else
{
throw new Exception("No link information found in object header.");
}
}
}
return(false);
}