linux-v4l2: Check udev fd events

Browse Source

udev_event_thread calls poll with two fds: the udev fd, and an eventfd
used for shutdown.  On FreeBSD we were hanging on shutdown in
udev_monitor_receive_device after receiving the eventfd event.

Now, if the udev fd reports no events skip the
udev_monitor_receive_device call.

At shutdown the loop will exit via os_event_try().

...

This commit is contained in:

500 Internal Server Error

Gitea Version: 1.28.0+dev-477-g8b6ad49a5f