/// <summary>
/// Helper method to return the device path given a DeviceInterfaceData structure and an InfoSet handle.
/// Used in 'FindDevice' so check that method out to see how to get an InfoSet handle and a DeviceInterfaceData.
/// </summary>
/// <param name="infoSetPointer">Handle to the InfoSet</param>
/// <param name="deviceInterfaceData">DeviceInterfaceData structure</param>
/// <returns>The device path or null if there was some problem</returns>
internal static string GetDevicePath(IntPtr infoSetPointer, ref Win32USB.DeviceInterfaceData deviceInterfaceData)
{
uint requiredSize = 0;
// Get the device interface details
if (Win32USB.SetupDiGetDeviceInterfaceDetail(infoSetPointer, ref deviceInterfaceData, IntPtr.Zero, 0, ref requiredSize, IntPtr.Zero) == false)
{
var deviceInterfaceDetailData = new Win32USB.DeviceInterfaceDetailData();
if (IntPtr.Size == 8)
{
deviceInterfaceDetailData.Size = 8;
}
else
{
deviceInterfaceDetailData.Size = 5;
}
if (Win32USB.SetupDiGetDeviceInterfaceDetail(infoSetPointer, ref deviceInterfaceData, ref deviceInterfaceDetailData, requiredSize, ref requiredSize, IntPtr.Zero))
{
return(deviceInterfaceDetailData.DevicePath);
}
}
return(null);
}
protected override void OnHandleDestroyed(EventArgs e)
{
base.OnHandleDestroyed(e);
Win32USB.UnregisterDeviceNotification(messagePump.usbEventsSubscription);
messagePump.Handle = IntPtr.Zero;
}
protected override void OnHandleCreated(EventArgs e)
{
base.OnHandleCreated(e);
messagePump.Handle = Handle;
messagePump.usbEventsSubscription = Win32USB.RegisterForUsbEvents(Handle, HID.Guid);
}
private bool GetCaps()
{
InputReportLength = -1;
OutputReportLength = -1;
if (Win32USB.HidD_GetPreparsedData(handle, out IntPtr preparsedData))
{
try
{
Win32USB.HidP_GetCaps(preparsedData, out Win32USB.HidCaps caps);
InputReportLength = caps.InputReportByteLength;
OutputReportLength = caps.OutputReportByteLength;
}
finally
{
Win32USB.HidD_FreePreparsedData(ref preparsedData);
}
return(true);
}
else
{
Win32USB.CloseHandle(handle);
handle = null;
return(false);
}
}
public bool Start()
{
Dispose();
handle = Win32USB.CreateFile(
DevicePath,
Win32USB.GENERIC_READ | Win32USB.GENERIC_WRITE,
Win32USB.FILE_SHARE_READ | Win32USB.FILE_SHARE_WRITE,
IntPtr.Zero,
Win32USB.OPEN_EXISTING,
Win32USB.FILE_FLAG_OVERLAPPED,
IntPtr.Zero);
if (handle == null)
{
return(false);
}
if (GetCaps() == false)
{
return(false);
}
Stream = new FileStream(handle, FileAccess.ReadWrite, Math.Max(InputReportLength, OutputReportLength), true);
return(true);
}
public static IEnumerable <DeviceInfo> GetDevices(ushort vendorID, ushort productID)
{
Guid gHid = HID.Guid;
IntPtr infoSetPointer = Win32USB.SetupDiGetClassDevs(ref gHid, null, IntPtr.Zero, Win32USB.DIGCF_DEVICEINTERFACE | Win32USB.DIGCF_PRESENT);
try
{
var deviceInterfaceData = new Win32USB.DeviceInterfaceData();
deviceInterfaceData.Size = Marshal.SizeOf(deviceInterfaceData);
int index = 0;
while (Win32USB.SetupDiEnumDeviceInterfaces(infoSetPointer, 0, ref gHid, (uint)index, ref deviceInterfaceData))
{
string devicePath = GetDevicePath(infoSetPointer, ref deviceInterfaceData);
if (devicePath != null)
{
if (vendorID == 0 && productID == 0)
{
yield return(new DeviceInfo(devicePath));
}
else
{
if (DeviceInfo.ParseDevicePath(devicePath, out ushort localVendorID, out ushort localProductID, out uint localIdentifier) &&
localVendorID == vendorID && localProductID == productID)
{
yield return(new DeviceInfo(devicePath));
}
}
}
index++;
}
}
finally
{
Win32USB.SetupDiDestroyDeviceInfoList(infoSetPointer);
}
}
