device filtering support

[Xiaofan Chen]

On Wed, Feb 8, 2012 at 4:45 PM, Hans de Goede <hdegoede at redhat.com> wrote:
> As said before, if class filtering is non trivial, don't
> bother implementing it. I just mentioned it because I already
> have filtering code in my usbredir code, and that does have class
> filtering so I thought it might be useful (for others) to have
> it in the libusb filter API too.

It is indeed useful use case.

> My filtering happens at a
> much higher level, after enumerating *all* the USB devices in the
> system, so the libusb level filtering is of little use to me.
>
> To be more specific, my filtering code is used to decide whether
> or not to *automatically* redirect a device. A user will always be
> able to manually redirect a device, so I still need to enumerate
> all devices.

Okay, what kind of information you need from *all* USB devices?
Some of them are easier to get, some of them are bit more
difficult (at least for Windows), say the speed information
or the topology information.

-- 
Xiaofan