hid.dll support

[Phil Lodwick]

Greetings,

I was introduced to Wine a few months ago and ran into a problem with an
application I wanted to use.  This application makes use of setupapi.dll and
hid.dll to communicate with a USB HID class device.  I quickly determined
that in this case using native dlls was not an option and created an
implementation of hid.dll.  This solution has worked fine for me.  

>From what I have gathered from monitoring the Wine community, making
something work for yourself is easy -- getting a general fix into Wine for
everybody to use, not so easy :-)   There is much work that needs to be done
before I attempt to submit my first patch.  Please bear with me as I no doubt
ask newbie/dumb questions.

I would like to start with what I consider my most troubling solution.  My
gut tells me there must be a better way, but if there is, it is not obvious
to me.

>From MSDN: "To communicate with the device, call the
SetupDiGetDeviceInterfaceDetail function. This function returns device
information in an SP_DEVICE_INTERFACE_DETAIL_DATA structure. The DevicePath
member provides the symbolic link name, which can be used in the CreateFile
function to access the device."

On Windows this DevicePath takes the form:

\\?\hid#vid_0c27&pid_3bfa#6&11440ca5&0&0000#{4d1e55b2-f16f-11cf-88cb-00111100
0030}

Obviously, if we were to call Wine's implementation of CreateFile with this
path, we would not be opening the correct file to communicate with the
device.

My solution is to have SetupDiGetDeivceInterfaceDetail return a special
escape string that we can escape in CreateFile to indicate we are really
talking about getting a file descriptor for an open USB HID device.

There already seems to be precedence in CreateFile for this type of escape
mechanism.  Currently it appears to be checking for:

	\\??\\pipe\\
	\\??\\MAILSLOT\\

Does my solution for adding a third special escape sequence (\\??\\HID\\)
seem acceptable?

If this is the wrong approach, has there been anybody who has thought about
this problem and what the correct approach would be?

Thanks,
Phil