Remove the redundant s_populate_mutex and only use
ControllerInterface::m_devices_population_mutex instead to prevent a
deadlock caused by locking them in opposite orders.
The device population functions in the win32 InputBackend previously
locked s_populate_mutex first before calling various functions that
locked m_devices_population_mutex. This normally worked but
ControllerInterface::RefreshDevices locks m_devices_population_mutex
first and then calls HandleWindowChange which then locked
s_populate_mutex, potentially causing the deadlock.
Fix this by using PlatformPopulateDevices to lock
m_devices_population_mutex before running the code that was previously
protected by s_populate_mutex. The functions in question lock
m_devices_population_mutex anyway, so this shouldn't meaningfully
increase contention on the lock.
Reproduction steps:
* Let Dolphin finish startup.
* In Win32.cpp::OnDevicesChanged set a breakpoint on the call to
PlatformPopulateDevices. When the breakpoint is triggered the function
will have locked s_populate_mutex, but since PlatformPopulateDevices
won't have run yet m_devices_population_mutex will still be unlocked.
* Unplug a device from your computer.
* Wait for the breakpoint to trigger. (At this point you can plug the
device back in).
* Freeze the ntdll.dll!TppWorkerThread() that triggered the breakpoint.
* Resume Dolphin and start a game.
* Core::EmuThread will call ControllerInterface::ChangeWindow which
calls RefreshDevices. It locks m_devices_population_mutex, then calls
InputBackend::HandleWindowChange, which tries to lock
s_populate_mutex.
* Unfreeze ntdll.dll!TppWorkerThread().
At this point EmuThread and TppWorkerThread are deadlocked. The UI is
still responsive since the Host thread is unaffected, but trying to stop
the game or close Dolphin normally will fail since EmuThread is unable
to stop.
Verify a touchpad is present before polling it for input. Without this
check the Debug log is spammed with the message "error: Parameter
'touchpad' is invalid" if you have a controller without a touchpad.
One would think every touchpad supports at least 1 finger, but in case
there's some weird edge case check the finger count to be sure.
This is an Android continuation of bc95c00. We now call
InputDetector::Update immediately after receiving an input event from
Android instead of periodically calling it in a sleep loop. This
improves detection of very short inputs, which are especially likely to
occur for volume buttons on phones (or at least on my phone) if you
don't intentionally keep them held down.
In NandPaths.cpp, the `std::initializer_list<char>` of illegal characters has been turned into a `char[]` (similar to the one in GameList.cpp).
The reverse iteration in ResourcePack.cpp seemed to provide no benefits, and doing without it it seemed to have no ill effects.
In WiimoteReal.cpp, JitRegCache.cpp, lambda predicates were replaced by pointers to member functions because ranges algorithms are able invoke those.
In ConvertDialog.cpp, the `std::mem_fn` helper was removed because ranges algorithms are able to handle pointers to member functions as predicates.
In DITSpecification.cpp, MaterialAsset.cpp, and ShaderAsset.cpp, lambda predicates were replaced by pointers to member functions because ranges algorithms are able invoke those.
In NetPlayClient.cpp, the non-trivial `NetPlay::Player` elements were being passed by value in `NetPlayClient::DoAllPlayersHaveGame()`. This has been fixed.
In WIABlob.cpp, the second example's predicate was returning the `std::optional` by value instead of implicitly converting it to a bool. This has been fixed.
In DSPCore.cpp, there were two `std::fill` uses that could be simplified using `std::fill_n`. Due to their proximity with other `std::fill` algorithms being modernized with ranges, I chose to make these examples into the rare `std::ranges::fill_n`.
With 12 uses of `JoinStrings` in the codebase vs 36 uses of `fmt::join`, fmtlib's range adapter for string concatenation with delimiters is clearly the preferred option.
Dentomologist