public async void SendFileAsync(string addr, string filepath)
{
Message meta = Message.CreateMeta(filepath, PackSize);
string status = "";
long continueId = 0;
try
{
status = "Wait Confirmation";
IPEndPoint remoteEP = new IPEndPoint(IPAddress.Parse(addr), ReceiverPort);
UdpSend(remoteEP, meta);
await WaitMessage(
msg => msg.Type == MsgType.Continue,
(remoteEP, msg) => continueId = msg.PackID);
if (continueId == -1)
{
OnTransferError?.Invoke(new State(ActionCode.FileSend, StateCode.Error, "Request rejected"));
return;
}
remoteEP.Port = TransferPort;
status = "Transferring";
TcpSetupStream(remoteEP, ns =>
{
using FileStream fs = new FileStream(filepath, FileMode.Open, FileAccess.Read);
byte[] bs = null;
Message dataMsg = new Message {
PackID = continueId, Data = new byte[PackSize]
};
fs.Seek((continueId - 1) * PackSize, SeekOrigin.Begin);
while (fs.Length - fs.Position > PackSize)
{
fs.Read(dataMsg.Data, 0, PackSize);
bs = dataMsg.ToBytes();
ns.Write(bs, 0, bs.Length);
ns.Flush();
dataMsg.PackID++;
OnPackTransfered?.Invoke((fs.Position / fs.Length));
}
fs.Read(dataMsg.Data, 0, (int)(fs.Length - fs.Position));
bs = dataMsg.ToBytes();
ns.Write(bs, 0, bs.Length);
ns.Flush();
});
OnTransferDone?.Invoke(new State(ActionCode.FileSend, StateCode.Success, ""));
}
catch (OperationCanceledException)
{
OnTransferError?.Invoke(new State(ActionCode.FileSend, StateCode.Error, status + " Timeout"));
}
catch (SocketException e)
{
OnTransferError?.Invoke(new State(ActionCode.FileSend, StateCode.Error, e.Message));
}
}
private void ReceiveFile(IPEndPoint remoteEP, Message meta)
{
int continueId = LoadMetaFile(meta);
UdpSend(remoteEP, new Message {
PackID = continueId
});
TcpAcceptStream(ns =>
{
using (FileStream metafs = new FileStream(meta.Filename + ".meta", FileMode.Open))
using (FileStream fs = new FileStream(meta.Filename, FileMode.OpenOrCreate))
using (SHA256 sha = SHA256.Create())
{
Message data;
byte[] bs = new byte[meta.PackSize + 9];
for (int i = continueId - 1; i < meta.PackCount - 1; i++)
{
ns.Read(bs, 0, meta.PackSize + 9);
data = Message.Parse(bs);
fs.Seek(0, SeekOrigin.End);
fs.Write(data.Data, 0, meta.PackSize);
metafs.Seek(-8, SeekOrigin.End);
metafs.Write(Utils.GetBytes(data.PackID + 1), 0, 8);
fs.Flush(); metafs.Flush();
OnPackTransfered?.Invoke((i / meta.PackCount));
}
ns.Read(bs, 0, meta.PackSize + 9);
data = Message.Parse(bs);
fs.Write(data.Data, 0, (int)(meta.Size - meta.PackSize * (meta.PackCount - 1)));
fs.Flush();
fs.Seek(0, SeekOrigin.Begin);
metafs.Seek(0, SeekOrigin.Begin);
byte[] metahs = new byte[256];
metafs.Read(metahs, 0, 256);
byte[] hash = new byte[256];
byte[] t = sha.ComputeHash(fs);
Array.Copy(t, 0, hash, 0, t.Length);
if (!hash.SequenceEqual(metahs))
{
throw new ChecksumMismatchException("Checksum not match, file may be collapsed.");
}
}
File.Delete(meta.Filename + ".meta");
});
}
