static TeaFile <T> Append(Stream stream, bool ownsStream, Stream headerReadStream, ItemDescriptionElements elementsToValidate = ItemDescriptionElements.All)
{
var tf = new TeaFile <T>();
try
{
TeaFileDescription description;
tf.core = new TeaFileCore(stream, ownsStream);
// A file opened for appending, cannot be read. Therefore we create a second file, read it and assign its description to the current TeaFile<> instance.
using (var tfheader = OpenRead(headerReadStream, false, elementsToValidate)) // we pass headerStream ownership to tfheader, so it will be closed after header reaeding.
{
description = tfheader.Description;
if (!tfheader.core.CanAppend)
{
throw new IOException("Cannot append to file because it has preallocated space between the end of the item area and the end of the file.");
}
tf.core.Assign(tfheader.ItemAreaStart, tfheader.core.ItemAreaEndMarker);
}
// if the stream is a filestream that was opened in FileMode.Append, this call is redundant.
// this line is here for the allowed case were the stream and headerstream point to the same stream.
tf.SetFilePointerToEnd();
tf.core.Description = description;
tf.buffer = new SafeBuffer <T>(stream);
return(tf);
}
catch (Exception)
{
tf.Dispose();
throw;
}
}
