private Stream EnsureStream()
{
if (_stream is null)
{
var name = _heap.GetObjectName(_slot.NameHeapOffset);
var filePath = H5Utils.ConstructExternalFilePath(name, _datasetAccess);
if (!File.Exists(filePath))
{
throw new Exception($"External file '{filePath}' does not exist.");
}
_stream = File.OpenRead(filePath);
_stream.Seek((long)_slot.Offset, SeekOrigin.Begin);
}
return(_stream);
}
public H5NamedReference GetTarget(H5LinkAccess linkAccess)
{
// this file
if (string.IsNullOrWhiteSpace(this.ObjectPath))
{
try
{
var reference = this.Parent.InternalGet(this.Value, linkAccess);
reference.Name = this.Name;
return(reference);
}
catch (Exception ex)
{
return(new H5NamedReference(this.Name, Superblock.UndefinedAddress)
{
Exception = ex
});
}
}
// external file
else
{
try
{
var absoluteFilePath = H5Utils.ConstructExternalFilePath(this.Parent.File, this.Value, linkAccess);
var objectPath = this.ObjectPath;
var externalFile = H5Cache.GetH5File(this.Parent.Context.Superblock, absoluteFilePath);
return(externalFile.InternalGet(objectPath, linkAccess));
}
catch (Exception ex)
{
return(new H5NamedReference(this.Name, Superblock.UndefinedAddress)
{
Exception = ex
});
}
}
}
private void ReadExternalFileList(Span <byte> buffer, ExternalFileListMessage externalFileList, H5DatasetAccess datasetAccess)
{
var bufferOffset = 0;
var remainingSize = buffer.Length;
foreach (var slotDefinition in externalFileList.SlotDefinitions)
{
var length = Math.Min(remainingSize, (int)slotDefinition.Size);
var heap = externalFileList.Heap;
var name = heap.GetObjectName(slotDefinition.NameHeapOffset);
var filePath = H5Utils.ConstructExternalFilePath(name, datasetAccess);
if (!File.Exists(filePath))
{
throw new Exception($"External file '{filePath}' does not exist.");
}
try
{
using var fileStream = File.OpenRead(filePath);
fileStream.Seek((long)slotDefinition.Offset, SeekOrigin.Begin);
var actualLength = Math.Min(length, fileStream.Length);
var currentBuffer = buffer.Slice(bufferOffset, (int)actualLength);
fileStream.Read(currentBuffer);
}
catch
{
throw new Exception($"Unable to open external file '{filePath}'.");
}
bufferOffset += length;
remainingSize -= length;
}
}
