/// <summary>
/// Reads or Writes data (depending on the <see cref="EpNum"/>) to/from the current <see cref="UsbEndpointReader"/>.
/// </summary>
/// <param name="buffer">The buffer for the tranfer.</param>
/// <param name="offset">The position in buffer to start storing the data.</param>
/// <param name="count">The number of bytes to send or the maximum number of bytes to receive.</param>
/// <param name="timeout">Maximum time to wait for the transfer to complete. If the transfer times out, the IO operation will be cancelled.</param>
/// <returns>
/// Number of bytes transmitted or less than zero if an error occured.
/// </returns>
public int Transfer(byte[] buffer, int offset, int count, int timeout)
{
if (mbDisposed)
{
return((int)ErrorCodes.ENODEV);
}
if (!TransferLock.WaitOne(0, false))
{
return((int)ErrorCodes.EBUSY);
}
int ret = -1;
try
{
lock (oLockTransferContext)
Context.Setup(buffer, offset, count, timeout, true);
ret = transferSync(Context);
}
catch (Exception ex)
{
ret = (int)ErrorCodes.EEXCEPTION;
UsbGlobals.Error(this, ex.ToString(), "Transfer", ret);
}
finally
{
freeAsync(Context);
TransferLock.Release();
}
return(ret);
}
private void startStopReadThread()
{
if (IsDisposed)
{
return;
}
if (mDataReceivedEnabled)
{
mEventCancelReadThread.Set();
int iLoopCount = 0;
while (mthReadThread.IsAlive)
{
iLoopCount++;
if ((iLoopCount) > 1000)
{
mthReadThread.Abort();
UsbGlobals.Error(this, "Thread could not be gracefully stopped.", "startStopReadThread", (int)ErrorCodes.ETHREADABORT);
break;
}
Application.DoEvents();
Thread.Sleep(1);
if (Context.mContext.IsValid)
{
cancelAsync(Context);
}
}
iLoopCount = 0;
while (mDataReceivedEnabled)
{
iLoopCount++;
Application.DoEvents();
Thread.Sleep(1);
if ((iLoopCount) > 1000)
{
throw new LibUsbException(this, "startStopReadThread: The read thread is stalled.");
}
}
mthReadThread = null;
}
else
{
if (!TransferLock.WaitOne(0, false))
{
UsbGlobals.Error(this, "Read thread could not be started because a transfer is allready pending.", "startStopReadThread", (int)ErrorCodes.EBUSY);
return;
}
mEventCancelReadThread.Reset();
lock (oLockTransferContext)
Context.Setup(new byte[mReadBufferSize], 0, mReadBufferSize, Timeout.Infinite, false);
mthReadThread = new Thread(ReadData);
mthReadThread.Start(Context);
Application.DoEvents();
}
}
