Darwin: enable non-exclusive device usage

[ilyalasy]

When I use device.open(), device inputs are not accessible on any application other than my script code.
How can I fix that?
Platform: macOS (ARM)

[prusnak]

Duplicate of libusb/hidapi#27

It seems that the underlying library does not allow it

[ilyalasy]

This PR fixes it, isn't it?

[prusnak]

So it seems that all we need to do is export the following functions and set them accordingly.

void HID_API_EXPORT_CALL hid_darwin_set_open_exclusive(int open_exclusive)
int HID_API_EXPORT_CALL hid_darwin_get_open_exclusive(void)
int HID_API_EXPORT_CALL hid_darwin_is_device_open_exclusive(hid_device *dev)

@ilyalasy would you like to create a PR for this?

[ilyalasy]

So it seems that all we need to do is export the following functions and set them accordingly.

void HID_API_EXPORT_CALL hid_darwin_set_open_exclusive(int open_exclusive)
int HID_API_EXPORT_CALL hid_darwin_get_open_exclusive(void)
int HID_API_EXPORT_CALL hid_darwin_is_device_open_exclusive(hid_device *dev)

@ilyalasy would you like to create a PR for this?

Don't have experience with cython, but I can try

[vulpes2]

@prusnak I'm interested in submitting a fix, but I've never used cython before. Can you give me some pointers on how to conditionally export these (only on darwin)? I haven't found anything relevant in cython's docs about this so far.

[prusnak]

e. Can you give me some pointers on how to conditionally export these (only on darwin)?

ISTM that Cython does not export something it could not find, so just adding the functions to chid.pxd without condition should work and they will be exported on macOS and won't otherwise

We would need to test this hypothesis

[vulpes2]

I have a draft PR with all the darwin-specific functions, they seem to work as expected but I can't get conditional include to work. Some help would be appreciated to get this into a usable shape.

Edit: looks like there is no way to export those functions conditionally, so the c functions have to be stubbed out in chid.pxd, and the darwin-specific functions in hid.pyx can raise exceptions if they're called when running on a non-darwin platform.