private void OnDownloadProgressAsync(DownloadProgressEventArgs e)
{
var handler = this.DownloadProgress;
if (handler != null)
{
handler.BeginInvoke(this,
e,
handler.EndInvoke,
null);
}
}
public async Task<bool> DownloadAsync(FtpFile ftpFile,
Stream stream,
CancellationToken cancellationToken)
{
using (await this._mutex.LockAsync(cancellationToken))
{
var controlComplexSocket = await this.EnsureConnectionAndAuthenticationAsync(cancellationToken);
if (controlComplexSocket == null)
{
return false;
}
{
var success = await this.GotoParentDirectoryAsync(controlComplexSocket,
ftpFile,
cancellationToken);
if (!success)
{
return false;
}
}
long bytesTotal;
// sending SIZE
// reading SIZE
{
var success = await this.SendAndLogAsync(controlComplexSocket,
cancellationToken,
"SIZE {0}",
ftpFile.FileName);
if (!success)
{
return false;
}
var ftpReply = await this.ReceiveAndLogAsync(controlComplexSocket,
cancellationToken);
if (!ftpReply.Success)
{
return false;
}
if (!long.TryParse(ftpReply.ResponseMessage,
out bytesTotal))
{
return false;
}
}
// sending PASV
// reading PASV
var transferComplexSocket = await this.GetPassiveComplexSocketAsync(controlComplexSocket,
cancellationToken);
if (transferComplexSocket == null)
{
return false;
}
{
FtpReply ftpReply;
using (transferComplexSocket)
{
// sending RETR
// open transfer socket
// reading RETR (150 Opening BINARY mode data connection...)
var success = await this.SendAndLogAsync(controlComplexSocket,
cancellationToken,
"RETR {0}",
ftpFile.FileName);
if (!success)
{
return false;
}
success = await transferComplexSocket.ConnectAsync(cancellationToken);
if (!success)
{
return false;
}
ftpReply = await this.ReceiveAndLogAsync(controlComplexSocket,
cancellationToken);
if (!ftpReply.Success)
{
return false;
}
{
this.WaitBeforeReceive();
// reading transfer socket
var rawFtpResponse = await transferComplexSocket.Socket.ReceiveAsync(this.ChunkReceiveBufferSize,
transferComplexSocket.GetSocketAsyncEventArgs,
cancellationToken,
bytesTotal,
bytesReceived =>
{
var downloadProgressEventArgs = new DownloadProgressEventArgs(bytesReceived,
bytesTotal);
this.OnDownloadProgressAsync(downloadProgressEventArgs);
});
if (!rawFtpResponse.Success)
{
return false;
}
stream.Write(rawFtpResponse.Buffer,
0,
rawFtpResponse.Buffer.Length);
}
}
if (!ftpReply.Completed)
{
// reading RETR (226 Transfer complete)
ftpReply = await this.ReceiveAndLogAsync(controlComplexSocket,
cancellationToken);
if (!ftpReply.Success)
{
return false;
}
}
}
}
return true;
}
