/// <summary>
/// Read a file chunk request`
/// </summary>
/// <param name="from">Origin</param>
/// <param name="filename">Filename to read from</param>
/// <param name="offset">Offset in the file</param>
/// <param name="maxLength">Maximum chunk length</param>
/// <returns>Number of bytes read</returns>
public static int ReadFileChunkRequest(ReadOnlySpan <byte> from, out string filename, out uint offset, out uint maxLength)
{
FileChunkHeader header = MemoryMarshal.Cast <byte, FileChunkHeader>(from)[0];
int bytesRead = Marshal.SizeOf(header);
// Read header
offset = header.Offset;
maxLength = header.MaxLength;
// Read filename
ReadOnlySpan <byte> unicodeFilename = from.Slice(bytesRead, (int)header.FilenameLength);
filename = Encoding.UTF8.GetString(unicodeFilename);
bytesRead += (int)header.FilenameLength;
return(AddPadding(bytesRead));
}
private void HandleFileSend(FileRequestMessage requestMessage)
{
if (!requestMessage.RequestedFile.Exists)
{
ClientProtocol.SendFileTransferFailure(requestMessage.RequestedFile);
return;
}
long chunkIndex = requestMessage.Header.ChunkIndex;
using (FileStream file = requestMessage.RequestedFile.OpenForRead())
{
FileChunkHeader header = new FileChunkHeader();
header.ChunkCount = (int)Math.Ceiling((double)file.Length / Settings.FileChunkSize);
header.ChunkIndex = chunkIndex;
header.Id = requestMessage.Header.Id;
header.Hash = requestMessage.RequestedFile.Hash;
using (FileChunkMessage message = new FileChunkMessage(header))
{
long offset = chunkIndex * Settings.FileChunkSize;
int length = (int) (offset + Settings.FileChunkSize > file.Length ? file.Length - offset : Settings.FileChunkSize);
byte[] chunk = new byte[length];
file.Seek(offset, SeekOrigin.Begin);
file.Read(chunk, 0, chunk.Length);
try
{
ClientProtocol.AddDataToMessage(message, chunk);
ClientProtocol.SendMessage(message);
}
catch (Exception e)
{
throw e;
}
}
}
}
