WinUSB WritePipe method failure

[Morice Yohan]

Hi all,

I am facing some issues when I try to send data on bulk pipe.

I am able to get the handle after calling CreateFile() method.

IntPtr handleDevice = Kernel32ApiCalls.CreateFile(devicePath, GENERIC_READ | GENERIC_WRITE, 0, IntPtr.Zero, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL | FILE_FLAG_OVERLAPPED, IntPtr.Zero);

Then I am able to get the WinUSB handle by calling WinUsb_Initialize() method.

WinUsbApiCalls.WinUsb_Initialize(handleDevice, out handle);

I haven't yet tested ReadPipe() and ControlTransfer() methods, but I am able to call all others WinUsb methods except WritePipe() method.

It is declared as follow in my code.

[DllImport("winusb.dll", SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
internal static extern bool WinUsb_WritePipe(IntPtr InterfaceHandle, uint PipeID, byte[] Buffer, uint BufferLength, ref uint LengthTransferred, IntPtr Overlapped);

And I call it as follow :

bool success = WinUsbApiCalls.WinUsb_WritePipe(handle, pipe, sendBuffer, sizeToSend, ref lengthTransferred, IntPtr.Zero);

where:

- sendBuffer is defined as new byte[] {0x01, 0x0D, 0x00}

- sizeToSend is equal to 3

- lengthTransferred is initialized to 0

When I test it, I encountered 'PInvokeStackImbalance' exception.


Few years ago, I have made a shared library which managed WinUsb methods correctly.

So I have tested to compile a C dll which manages only WinUsb methods call without any intelligency.

[DllImport("usb.dll", CallingConvention = CallingConvention.Cdecl, SetLastError = true)]
internal static extern int usbWrite(IntPtr InterfaceHandle, uint PipeID, byte[] Buffer, uint BufferLength);

int success = UsbApiCalls.usbWrite(handle, pipe, sendBuffer, sizeToSend);

and on the dll side it works like that:

- header file:

typedef int (__stdcall *winusb_writepipe) (WINUSB_INTERFACE_HANDLE, unsigned char, unsigned char*, unsigned long, unsigned long*, LPOVERLAPPED);
extern winusb_writepipe _wusb_write;

- source file:

winusb_writepipe _wusb_write;

HINSTANCE dllLib = LoadLibrary("path\\winusb");
if (dllLib != NULL)
{
_wusb_write = (winusb_writepipe) GetProcAddress(dllLib,"WinUsb_WritePipe");
}

DLLEXPORT int usbWrite(PWINUSB_INTERFACE_HANDLE handle, unsigned char pipe, unsigned char* buffer, unsigned long size){
FILE * fp = fopen ("USB.txt", "w+");
unsigned long lpBytesWritten=0;
int err = _wusb_write(handle, pipe, buffer, size, &lpBytesWritten, NULL);
if(err == 1){
if(lpBytesWritten != size){
fprintf(fp, "Size sent incorrect.\n");
return 0;
}
} else {
fprintf(fp, "\nLast error : %d\n", (int) GetLastError());
}
fclose(fp);
return err;
}

And then I obtain an INVALID_PARAMETER error.

I did not see what is wrong, because for me, in both cases I respect the WritePipe() method requirements.

I provide all parameters and I specify "Null" for Overlapped structure to force synchronous communication with USB port.

It seems that there is a problem to call WritePipe method without specifying an Overlapped structure.

Can someone help me about this issue ?

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