private String GetStringSafe(Byte id)
{
if (id == 0)
{
return(null);
}
if (languages == null)
{
Byte[] buff = new Byte[256];
int len = GetDescriptor((Byte)UsbDescriptorType.String, 0, 0, buff, 0, buff.Length);
if (len > 1)
{
languages = new short[len / 2 - 1];
for (int i = 0; i < languages.Length; i++)
{
languages[i] = BitConverter.ToInt16(buff, i * 2 + 2);
}
}
}
short language = (languages == null || languages.Length == 0) ? (short)0 : languages[0];
String s = UsbStringDescriptor.GetStringFromDevice(this, id, language);
if (s == null)
{
return(s);
}
return(s.Trim(' ', '\0'));
}
/// <summary>
/// return a down stream external hub
/// </summary>
/// <returns>Downstream external hub</returns>
internal UsbDevice GetDevice()
{
if (!PortIsDeviceConnected)
{
return(null);
}
// Copy over some values from the Port class
// Ya know, I've given some thought about making Device a derived class...
UsbDevice device = new UsbDevice
{
DevicePortNumber = PortPortNumber,
DeviceHubDevicePath = PortHubDevicePath,
DeviceDescriptor = PortDeviceDescriptor
};
// Open a handle to the Hub device
IntPtr h = CreateFile(PortHubDevicePath, GENERIC_WRITE, FILE_SHARE_WRITE, IntPtr.Zero, OPEN_EXISTING, 0,
IntPtr.Zero);
if (h.ToInt32() == INVALID_HANDLE_VALUE)
{
return(device);
}
int nBytesReturned;
int nBytes = BUFFER_SIZE;
// We use this to zero fill a buffer
string nullString = new string((char)0, BUFFER_SIZE / Marshal.SystemDefaultCharSize);
// The iManufacturer, iProduct and iSerialNumber entries in the
// Device Descriptor are really just indexes. So, we have to
// request a String Descriptor to get the values for those strings.
if (PortDeviceDescriptor.iManufacturer > 0)
{
// build a request for string descriptor
UsbDescriptorRequest request = new UsbDescriptorRequest
{
ConnectionIndex = PortPortNumber,
SetupPacket =
{
// Language Code
wIndex = 0x409,
wValue = (short)((USB_STRING_DESCRIPTOR_TYPE << 8) + PortDeviceDescriptor.iManufacturer)
}
};
request.SetupPacket.wLength = (short)(nBytes - Marshal.SizeOf(request));
// Geez, I wish C# had a Marshal.MemSet() method
IntPtr ptrRequest = Marshal.StringToHGlobalAuto(nullString);
Marshal.StructureToPtr(request, ptrRequest, true);
// Use an IOCTL call to request the String Descriptor
if (DeviceIoControl(h, IOCTL_USB_GET_DESCRIPTOR_FROM_NODE_CONNECTION, ptrRequest, nBytes, ptrRequest,
nBytes, out nBytesReturned, IntPtr.Zero))
{
// The location of the string descriptor is immediately after
// the Request structure. Because this location is not "covered"
// by the structure allocation, we're forced to zero out this
// chunk of memory by using the StringToHGlobalAuto() hack above
IntPtr ptrStringDesc = new IntPtr(ptrRequest.ToInt32() + Marshal.SizeOf(request));
UsbStringDescriptor stringDesc =
(UsbStringDescriptor)Marshal.PtrToStructure(ptrStringDesc, typeof(UsbStringDescriptor));
device.DeviceManufacturer = stringDesc.bString;
}
Marshal.FreeHGlobal(ptrRequest);
}
if (PortDeviceDescriptor.iProduct > 0)
{
// build a request for string descriptor
UsbDescriptorRequest request = new UsbDescriptorRequest
{
ConnectionIndex = PortPortNumber,
SetupPacket =
{
// Language Code
wIndex = 0x409,
wValue = (short)((USB_STRING_DESCRIPTOR_TYPE << 8) + PortDeviceDescriptor.iProduct)
}
};
request.SetupPacket.wLength = (short)(nBytes - Marshal.SizeOf(request));
// Geez, I wish C# had a Marshal.MemSet() method
IntPtr ptrRequest = Marshal.StringToHGlobalAuto(nullString);
Marshal.StructureToPtr(request, ptrRequest, true);
// Use an IOCTL call to request the String Descriptor
if (DeviceIoControl(h, IOCTL_USB_GET_DESCRIPTOR_FROM_NODE_CONNECTION, ptrRequest, nBytes, ptrRequest,
nBytes, out nBytesReturned, IntPtr.Zero))
{
// the location of the string descriptor is immediately after the Request structure
IntPtr ptrStringDesc = new IntPtr(ptrRequest.ToInt32() + Marshal.SizeOf(request));
UsbStringDescriptor stringDesc =
(UsbStringDescriptor)Marshal.PtrToStructure(ptrStringDesc, typeof(UsbStringDescriptor));
device.DeviceProduct = stringDesc.bString;
}
Marshal.FreeHGlobal(ptrRequest);
}
if (PortDeviceDescriptor.iSerialNumber > 0)
{
// build a request for string descriptor
UsbDescriptorRequest request = new UsbDescriptorRequest
{
ConnectionIndex = PortPortNumber,
SetupPacket =
{
// Language Code
wIndex = 0x409,
wValue = (short)((USB_STRING_DESCRIPTOR_TYPE << 8) + PortDeviceDescriptor.iSerialNumber)
}
};
request.SetupPacket.wLength = (short)(nBytes - Marshal.SizeOf(request));
// Geez, I wish C# had a Marshal.MemSet() method
IntPtr ptrRequest = Marshal.StringToHGlobalAuto(nullString);
Marshal.StructureToPtr(request, ptrRequest, true);
// Use an IOCTL call to request the String Descriptor
if (DeviceIoControl(h, IOCTL_USB_GET_DESCRIPTOR_FROM_NODE_CONNECTION, ptrRequest, nBytes, ptrRequest,
nBytes, out nBytesReturned, IntPtr.Zero))
{
// the location of the string descriptor is immediately after the Request structure
IntPtr ptrStringDesc = new IntPtr(ptrRequest.ToInt32() + Marshal.SizeOf(request));
UsbStringDescriptor stringDesc =
(UsbStringDescriptor)Marshal.PtrToStructure(ptrStringDesc, typeof(UsbStringDescriptor));
device.DeviceSerialNumber = stringDesc.bString;
}
Marshal.FreeHGlobal(ptrRequest);
}
// build a request for configuration descriptor
UsbDescriptorRequest dcrRequest = new UsbDescriptorRequest
{
ConnectionIndex = PortPortNumber,
SetupPacket = { wIndex = 0, wValue = USB_CONFIGURATION_DESCRIPTOR_TYPE << 8 }
};
dcrRequest.SetupPacket.wLength = (short)(nBytes - Marshal.SizeOf(dcrRequest));
// Geez, I wish C# had a Marshal.MemSet() method
IntPtr dcrPtrRequest = Marshal.StringToHGlobalAuto(nullString);
Marshal.StructureToPtr(dcrRequest, dcrPtrRequest, true);
// Use an IOCTL call to request the String Descriptor
if (DeviceIoControl(h, IOCTL_USB_GET_DESCRIPTOR_FROM_NODE_CONNECTION, dcrPtrRequest, nBytes,
dcrPtrRequest, nBytes, out nBytesReturned, IntPtr.Zero))
{
IntPtr ptrStringDesc = new IntPtr(dcrPtrRequest.ToInt32() + Marshal.SizeOf(dcrRequest));
device.BinaryDeviceDescriptors = new byte[nBytesReturned];
Marshal.Copy(ptrStringDesc, device.BinaryDeviceDescriptors, 0, nBytesReturned);
}
Marshal.FreeHGlobal(dcrPtrRequest);
// Get the Driver Key Name (usefull in locating a device)
UsbNodeConnectionDriverkeyName driverKey =
new UsbNodeConnectionDriverkeyName {
ConnectionIndex = PortPortNumber
};
nBytes = Marshal.SizeOf(driverKey);
IntPtr ptrDriverKey = Marshal.AllocHGlobal(nBytes);
Marshal.StructureToPtr(driverKey, ptrDriverKey, true);
// Use an IOCTL call to request the Driver Key Name
if (DeviceIoControl(h, IOCTL_USB_GET_NODE_CONNECTION_DRIVERKEY_NAME, ptrDriverKey, nBytes, ptrDriverKey,
nBytes, out nBytesReturned, IntPtr.Zero))
{
driverKey = (UsbNodeConnectionDriverkeyName)Marshal.PtrToStructure(ptrDriverKey,
typeof(
UsbNodeConnectionDriverkeyName
));
device.DeviceDriverKey = driverKey.DriverKeyName;
// use the DriverKeyName to get the Device Description and Instance ID
device.DeviceName = GetDescriptionByKeyName(device.DeviceDriverKey);
device.DeviceInstanceId = GetInstanceIdByKeyName(device.DeviceDriverKey);
}
Marshal.FreeHGlobal(ptrDriverKey);
CloseHandle(h);
return(device);
}
