private void allocTransfer(UsbEndpointBase endpointBase, bool ownsTransfer, int isoPacketSize, int count)
{
int numIsoPackets = 0;
if (isoPacketSize > 0)
numIsoPackets = count/isoPacketSize;
freeTransfer();
mTransfer = LibUsbTransfer.Alloc(numIsoPackets);
mOwnsTransfer = ownsTransfer;
mTransfer.Type = endpointBase.Type;
mTransfer.Endpoint = endpointBase.EpNum;
mTransfer.NumIsoPackets = numIsoPackets;
if (!mCompleteEventHandle.IsAllocated)
mCompleteEventHandle = GCHandle.Alloc(mTransferCompleteEvent);
mTransfer.PtrUserData = GCHandle.ToIntPtr(mCompleteEventHandle);
if (numIsoPackets > 0)
mTransfer.SetIsoPacketLengths(isoPacketSize);
}
/// <summary>
/// Perform a USB control transfer for multi-threaded applications using the <see cref="LibUsbEventHandler"/> class.
/// </summary>
/// <remarks>
/// <para>The direction of the transfer is inferred from the bmRequestType field of the setup packet.</para>
/// <para>The wValue, wIndex and wLength fields values should be given in host-endian byte order.</para>
/// <note type="tip" title="Libusb-1.0 API:"><seelibusb10 group="syncio"/></note>
/// </remarks>
/// <param name="deviceHandle">A handle for the device to communicate with.</param>
/// <param name="requestType">The request type field for the setup packet.</param>
/// <param name="request">The request field for the setup packet.</param>
/// <param name="value">The value field for the setup packet</param>
/// <param name="index">The index field for the setup packet.</param>
/// <param name="pData">A suitably-sized data buffer for either input or output (depending on direction bits within bmRequestType).</param>
/// <param name="dataLength">The length field for the setup packet. The data buffer should be at least this size.</param>
/// <param name="timeout">timeout (in milliseconds) that this function should wait before giving up due to no response being received. For an unlimited timeout, use value 0.</param>
/// <returns>
/// <list type="bullet">
/// <item>on success, the number of bytes actually transferred</item>
/// <item><see cref="LibUsbError.ErrorTimeout"/> if the transfer timed out</item>
/// <item><see cref="LibUsbError.ErrorPipe"/> if the control request was not supported by the device.</item>
/// <item><see cref="LibUsbError.ErrorNoDevice"/> if the device has been disconnected</item>
/// <item>another <see cref="LibUsbError"/> code on other failures</item>
/// </list>
/// </returns>
public static int ControlTransferAsync([In] LibUsbDeviceHandle deviceHandle,
byte requestType,
byte request,
short value,
short index,
IntPtr pData,
short dataLength,
int timeout)
{
LibUsbControlSetupHandle setupHandle = new LibUsbControlSetupHandle(requestType, request, value, index, pData, dataLength);
LibUsbTransfer transfer = new LibUsbTransfer(0);
ManualResetEvent completeEvent = new ManualResetEvent(false);
GCHandle gcCompleteEvent = GCHandle.Alloc(completeEvent);
transfer.FillControl(deviceHandle, setupHandle, DefaultAsyncDelegate, GCHandle.ToIntPtr(gcCompleteEvent), timeout);
int r = (int)transfer.Submit();
if (r < 0)
{
transfer.Free();
gcCompleteEvent.Free();
return r;
}
IntPtr pSessionHandle;
LibUsbSessionHandle sessionHandle = LibUsbEventHandler.SessionHandle;
if (sessionHandle == null)
pSessionHandle = IntPtr.Zero;
else
pSessionHandle = sessionHandle.DangerousGetHandle();
if (LibUsbEventHandler.IsStopped)
{
while (!completeEvent.WaitOne(0, false))
{
r = HandleEvents(pSessionHandle);
if (r < 0)
{
if (r == (int)LibUsbError.ErrorInterrupted)
continue;
transfer.Cancel();
while (!completeEvent.WaitOne(0, false))
if (HandleEvents(pSessionHandle) < 0)
break;
transfer.Free();
gcCompleteEvent.Free();
return r;
}
}
}
else
{
completeEvent.WaitOne(Timeout.Infinite, UsbConstants.EXIT_CONTEXT);
}
if (transfer.Status == LibUsbTansferStatus.TransferCompleted)
{
r = transfer.ActualLength;
if (r > 0)
{
byte[] ctrlDataBytes = setupHandle.ControlSetup.GetData(r);
Marshal.Copy(ctrlDataBytes, 0, pData, Math.Min(ctrlDataBytes.Length, dataLength));
}
}
else
r = (int)MonoLibUsbErrorFromTransferStatus(transfer.Status);
transfer.Free();
gcCompleteEvent.Free();
return r;
}
private static void TransferCallback(LibUsbTransfer pTransfer)
{
ManualResetEvent completeEvent = GCHandle.FromIntPtr(pTransfer.PtrUserData).Target as ManualResetEvent;
completeEvent.Set();
}
private static void DefaultAsyncCB(LibUsbTransfer transfer)
{
ManualResetEvent completeEvent = GCHandle.FromIntPtr(transfer.PtrUserData).Target as ManualResetEvent;
completeEvent.Set();
}
