This hack was added in 8f0cbefbe5, and the part of it in SI_DeviceGCAdapter is present on Android already, so I don't see any reason why this part doesn't apply to Android.
This is mostly a brainless merge, #ifdef-ing anything that doesn't match between the two while preserving common logic. I didn't rename any variables (although similar ones do exist), but I did change one log that was ERROR on android and NOTICE elsewhere to just always be NOTICE. Further merging will follow.
You can safely read or write non-atomic integers on multiple threads,
as long as every thread reading or writing it holds the same mutex
while doing so (here, s_mutex).
Removing the atomic accesses makes the code faster, but the actual
performance difference is probably negligible.
If libusb fails to initialize, an assertion fails, but if that happens before the main window is created, then Dolphin just dies. Now, the panic alert is properly shown and the user can ignore it.
SPDX standardizes how source code conveys its copyright and licensing
information. See https://spdx.github.io/spdx-spec/1-rationale/ . SPDX
tags are adopted in many large projects, including things like the Linux
kernel.
Unfortunately, it appears that using libusb's synchronous transfer API
from several threads causes nasty race conditions in event handling and
can lead to deadlocks, despite the fact that libusb's synchronous API
is documented to be perfectly fine to use from several threads (only
the manual polling functionality is supposed to require special
precautions).
Since usbdk was the only real reason for using a single libusb context
and since usbdk (currently) has so many issues with Dolphin, I think
dropping support for it in order to fix other backends is acceptable.
