ButtonManager is very different from how a normal input backend works,
and is making it hard for us to improve controller support on Android.
The following commits will add a new input backend in its place.
This second stack leads to JNI problems on Android, because ART fetches
the address and size of the original stack using pthread functions
(see GetThreadStack in art/runtime/thread.cc), and (presumably) treats
stack addresses outside of the original stack as invalid. (What I don't
understand is why some JNI operations on the CPU thread work fine
despite this but others don't.)
Instead of creating a second stack, let's borrow the approach ART uses:
Use pthread functions to find out the stack's address and size, then
install guard pages at an appropriate location. This lets us get rid
of a workaround we had in the MsgAlert function.
Because we're no longer choosing the stack size ourselves, I've made some
tweaks to where the put the guard pages. Previously we had a stack of
2 MiB and a safe zone of 512 KiB. We now accept stacks as small as 512 KiB
(used on macOS) and use a safe zone of 256 KiB. I feel like this should
be fine, but haven't done much testing beyond "it seems to work".
By the way, on Windows it was already the case that we didn't create
a second stack... But there was a bug in the implementation!
The code for protecting the stack has to run on the CPU thread, since
it's the CPU thread's stack we want to protect, but it was actually
running on EmuThread. This commit fixes that, since now this bug
matters on other operating systems too.
This is the first step of getting rid of the controller indirection
on Android. (Needing a way for touch controls to provide input
to the emulator core is the reason why the controller indirection
exists to begin with as far as I understand it.)
Because of the previous commit, this is needed to stop DolphinQt from
forgetting that the user pressed ignore whenever any part of the config
is changed.
This commit also changes the behavior a bit on DolphinQt: "Ignore for
this session" now applies to the current emulation session instead of
the current Dolphin launch. This matches how it already worked on
Android, and is in my opinion better because it means the user won't
lose out on important panic alerts in a game becase they played another
game first that had repeated panic alerts that they wanted to ignore.
For Android, this commit isn't necessary, but it makes the code cleaner.
We currently have two different code paths for initializing controllers:
Either the frontend (DolphinQt) can do it, or if the frontend doesn't do
it, the core will do it automatically when booting. Having these two
paths has caused problems in the past due to only one frontend being
tested (see de7ef47548). I would like to get rid of the latter path to
avoid further problems like this.
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.
These files cannot compile correctly as C, so there's no reason to have
ifdefs for C compatibility.
We switched to not checking the __cplusplus macro in our JNI code some
time ago, but it seems like I forgot to remove it from these two files.
We don't have a timeout like this on other platforms, and it doesn't
accomplish anything useful as far as I can tell. If you trigger it,
all that happens is that you don't get a working game and also can't
press Exit Emulation without Dolphin hanging (stuck in Core::Shutdown).
JosJuice