libusb: fix incorrect member name in bos_descriptor

[aokblast]

Summary

The bNumDeviceCapabilities is bNumDeviceCaps when it is imported to
libusb.

For a better compatibility, we should rename the member

See: https://github.com/libusb/libusb/commit/02ebafc85d3f219842cbabaf78abc8100b6656e5

[kevans]

This is likely to bite a few ports (see, for instance, https://grep.app/search?q=bNumDeviceCapabilities) -- that's not at all a large number of candidates, but I think it's worth a note in ^/UPDATING or something (macro to alias bNumDeviceCapabilities -> bNumDeviceCaps?)

[aokblast]

Is it worth to use something like:

#define bNumDeviceCapabilities bNumDeviceCaps

I have recommend the libusb upstream to do so on https://github.com/libusb/libusb/pull/1652

[kevans]

In D50740#1159918, @aokblast wrote:

Is it worth to use something like:

#define bNumDeviceCapabilities bNumDeviceCaps

I have recommend the libusb upstream to do so on https://github.com/libusb/libusb/pull/1652

Yeah, I think that's reasonable.

[aokblast]

Rebase to main and use macro to provide backward compatibility

[aokblast]

Please use this patch https://github.com/aokblast/freebsd-src/commit/d7e07f91d6f7673aa3467526b9e10784e98f6674.patch to merge. Thanks!

[markj]

In libusb20_desc.h I see a macro LIBUSB20_BOS_DESCRIPTOR which references the old field name. I'm not really sure what that macro is doing--should that be updated as well?

[aokblast]

In D50740#1167967, @markj wrote:

In libusb20_desc.h I see a macro LIBUSB20_BOS_DESCRIPTOR which references the old field name. I'm not really sure what that macro is doing--should that be updated as well?

The BOS_DESCRIPTOR in libusb20 is a dedicated structure for decode in libusb20 and the definition resides inside the libusb20_desc.c. Thus there is no reference from libusb10 structure.

For libusb10, we require a xfer and copy it into buffer directly. It will not be parsed by libusb20.

[markj]

In D50740#1167971, @aokblast wrote:

In D50740#1167967, @markj wrote:

In libusb20_desc.h I see a macro LIBUSB20_BOS_DESCRIPTOR which references the old field name. I'm not really sure what that macro is doing--should that be updated as well?

The BOS_DESCRIPTOR in libusb20 is a dedicated structure for decode in libusb20 and the definition resides inside the libusb20_desc.c. Thus there is no reference from libusb10 structure.

For libusb10, we require a xfer and copy it into buffer directly. It will not be parsed by libusb20.

Ok! Approved.

[aokblast]

Use define also in bos_descriptor