public ReceiveFile_Form(FileReceiver receiver, Socket client, HandshakeData data)
{
InitializeComponent();
this._receiver = receiver;
this._client = client;
this._data = data;
}
/// <summary>
/// Initialize handshake process and transfer initial information.
/// Actual data will be sent after handshake
/// </summary>
/// <param name="filename">Name of file to send</param>
/// <param name="len">Length of file</param>
public void Handshake(string filename, int len)
{
HandshakeData handshake = new HandshakeData(filename, len);
///Lets now serialize the handshake data. Create a binary
///formatter which will help convert the serializable object
///into binary form
BinaryFormatter formatter = new BinaryFormatter();
///Create a memory string that will hold the serialized data
using (MemoryStream stream = new MemoryStream())
{
///Now do the serialization of handshake data
formatter.Serialize(stream, handshake);
byte[] buffer = new byte[4];
///Send the length first
buffer = AppUtil.ToByteArray((int)stream.Length);
///Send the length first
SocketUtil.Send(this._socket, buffer);
///Send the data
SocketUtil.Send(this._socket, stream.ToArray());
///Now get the handshake response
HandshakeResponse response = this.GetHandshakeResponse();
///Close the stream as its not longer needed
stream.Close();
///If casting failed
if (response == null)
{
throw new Exception("The handshake process with receiver failed. Receiver sent an invalid response");
}
///Otherwise we check receivers response. If receiver denied receiving data...
if (!response.Continue)
{
throw new Exception("The destination computer denied to receive data");
}
}
///All is well and initial handshake process is completed.
///
}
/// <summary>
/// Perform handshake
/// </summary>
/// <remarks>Return true if client is asked to send
/// more data, false otherwise</remarks>
public HandshakeData Handshake(Socket client)
{
///Receive the length
byte[] buffer = new byte[4];
SocketUtil.Receive(client, buffer);
int incomingLen = AppUtil.FromByteArray(buffer);
if (incomingLen <= 0)
{
///Nothing to receive. Might be the connection is closing
///
return(null);
}
///Create a buffer to receive data
buffer = new byte[incomingLen];
SocketUtil.Receive(client, buffer);
HandshakeData handshake = null;
///Prepeare to deserialize data.
///
BinaryFormatter formatter = new BinaryFormatter();
using (MemoryStream stream = new MemoryStream(buffer))
{
///Deserialize
handshake = formatter.Deserialize(stream) as HandshakeData;
stream.Close();
}
///Cannot deserialize to handshake data
if (handshake == null)
{
///Close the connection
///
this.DiconnectClient(client);
}
return(handshake);
}
