Merge pull request #11193 from jordan-woyak/ciface-input-backend-interface

ControllerInterface: Add InputBackend interface.

Source/Core/DolphinLib.props

@@ -487,6 +487,7 @@
     <ClInclude Include="InputCommon\ControllerEmu\StickGate.h" />
     <ClInclude Include="InputCommon\ControllerInterface\ControllerInterface.h" />
     <ClInclude Include="InputCommon\ControllerInterface\CoreDevice.h" />
+    <ClInclude Include="InputCommon\ControllerInterface\InputBackend.h" />
     <ClInclude Include="InputCommon\ControllerInterface\DInput\DInput.h" />
     <ClInclude Include="InputCommon\ControllerInterface\DInput\DInput8.h" />
     <ClInclude Include="InputCommon\ControllerInterface\DInput\DInputJoystick.h" />
@@ -1111,6 +1112,7 @@
     <ClCompile Include="InputCommon\ControllerEmu\StickGate.cpp" />
     <ClCompile Include="InputCommon\ControllerInterface\ControllerInterface.cpp" />
     <ClCompile Include="InputCommon\ControllerInterface\CoreDevice.cpp" />
+    <ClCompile Include="InputCommon\ControllerInterface\InputBackend.cpp" />
     <ClCompile Include="InputCommon\ControllerInterface\DInput\DInput.cpp" />
     <ClCompile Include="InputCommon\ControllerInterface\DInput\DInputJoystick.cpp" />
     <ClCompile Include="InputCommon\ControllerInterface\DInput\DInputKeyboardMouse.cpp" />

Source/Core/InputCommon/CMakeLists.txt

@@ -56,6 +56,8 @@ add_library(inputcommon
   ControllerInterface/ControllerInterface.h
   ControllerInterface/CoreDevice.cpp
   ControllerInterface/CoreDevice.h
+  ControllerInterface/InputBackend.cpp
+  ControllerInterface/InputBackend.h
   ControllerInterface/MappingCommon.cpp
   ControllerInterface/MappingCommon.h
   ControllerInterface/Wiimote/WiimoteController.cpp

Source/Core/InputCommon/ControllerInterface/ControllerInterface.cpp

@@ -64,19 +64,19 @@ void ControllerInterface::Initialize(const WindowSystemInfo& wsi)
 // nothing needed for OSX and Quartz
 #endif
 #ifdef CIFACE_USE_SDL
-  ciface::SDL::Init();
+  m_input_backends.emplace_back(ciface::SDL::CreateInputBackend(this));
 #endif
 #ifdef CIFACE_USE_ANDROID
 // nothing needed
 #endif
 #ifdef CIFACE_USE_EVDEV
-  ciface::evdev::Init();
+  m_input_backends.emplace_back(ciface::evdev::CreateInputBackend(this));
 #endif
 #ifdef CIFACE_USE_PIPES
 // nothing needed
 #endif
 #ifdef CIFACE_USE_DUALSHOCKUDPCLIENT
-  ciface::DualShockUDPClient::Init();
+  m_input_backends.emplace_back(ciface::DualShockUDPClient::CreateInputBackend(this));
 #endif
 
   // Don't allow backends to add devices before the first RefreshDevices() as they will be cleaned
@@ -181,21 +181,15 @@ void ControllerInterface::RefreshDevices(RefreshReason reason)
     ciface::Quartz::PopulateDevices(m_wsi.render_window);
   }
 #endif
-#ifdef CIFACE_USE_SDL
-  ciface::SDL::PopulateDevices();
-#endif
 #ifdef CIFACE_USE_ANDROID
   ciface::Android::PopulateDevices();
 #endif
-#ifdef CIFACE_USE_EVDEV
-  ciface::evdev::PopulateDevices();
-#endif
 #ifdef CIFACE_USE_PIPES
   ciface::Pipes::PopulateDevices();
 #endif
-#ifdef CIFACE_USE_DUALSHOCKUDPCLIENT
+
-  ciface::DualShockUDPClient::PopulateDevices();
+  for (auto& backend : m_input_backends)
-#endif
+    backend->PopulateDevices();
 
   WiimoteReal::PopulateDevices();
 
@@ -242,18 +236,12 @@ void ControllerInterface::Shutdown()
   ciface::OSX::DeInit();
   ciface::Quartz::DeInit();
 #endif
-#ifdef CIFACE_USE_SDL
-  ciface::SDL::DeInit();
-#endif
 #ifdef CIFACE_USE_ANDROID
 // nothing needed
 #endif
-#ifdef CIFACE_USE_EVDEV
+
-  ciface::evdev::Shutdown();
+  // Empty the container of input backends to deconstruct and deinitialize them.
-#endif
+  m_input_backends.clear();
-#ifdef CIFACE_USE_DUALSHOCKUDPCLIENT
-  ciface::DualShockUDPClient::DeInit();
-#endif
 
   // Make sure no devices had been added within Shutdown() in the time
   // between checking they checked atomic m_is_init bool and we changed it.
@@ -384,15 +372,19 @@ void ControllerInterface::UpdateInput()
 
   // TODO: if we are an emulation input channel, we should probably always lock
   // Prefer outdated values over blocking UI or CPU thread (avoids short but noticeable frame drop)
-  if (m_devices_mutex.try_lock())
+  if (!m_devices_mutex.try_lock())
+    return;
+
+  std::lock_guard lk(m_devices_mutex, std::adopt_lock);
+
+  for (auto& backend : m_input_backends)
+    backend->UpdateInput();
+
+  for (const auto& d : m_devices)
   {
-    std::lock_guard lk(m_devices_mutex, std::adopt_lock);
+    // Theoretically we could avoid updating input on devices that don't have any references to
-    for (const auto& d : m_devices)
+    // them, but in practice a few devices types could break in different ways, so we don't
-    {
+    d->UpdateInput();
-      // Theoretically we could avoid updating input on devices that don't have any references to
-      // them, but in practice a few devices types could break in different ways, so we don't
-      d->UpdateInput();
-    }
   }
 }
 

Source/Core/InputCommon/ControllerInterface/ControllerInterface.h

@@ -12,6 +12,7 @@
 #include "Common/Matrix.h"
 #include "Common/WindowSystemInfo.h"
 #include "InputCommon/ControllerInterface/CoreDevice.h"
+#include "InputCommon/ControllerInterface/InputBackend.h"
 
 // enable disable sources
 #ifdef _WIN32
@@ -133,6 +134,8 @@ private:
   WindowSystemInfo m_wsi;
   std::atomic<float> m_aspect_ratio_adjustment = 1;
   std::atomic<bool> m_requested_mouse_centering = false;
+
+  std::vector<std::unique_ptr<ciface::InputBackend>> m_input_backends;
 };
 
 namespace ciface

Source/Core/InputCommon/ControllerInterface/DualShockUDPClient/DualShockUDPClient.cpp

@@ -130,7 +130,7 @@ private:
 public:
   void UpdateInput() override;
 
-  Device(std::string name, int index, std::string server_address, u16 server_port);
+  Device(std::string name, int index, std::string server_address, u16 server_port, u32 client_uid);
 
   std::string GetName() const final override;
   std::string GetSource() const final override;
@@ -150,13 +150,15 @@ private:
   bool m_prev_touch_valid = false;
   int m_touch_x = 0;
   int m_touch_y = 0;
-  std::string m_server_address;
+  const std::string m_server_address;
-  u16 m_server_port;
+  const u16 m_server_port;
 
   s16 m_touch_x_min;
   s16 m_touch_y_min;
   s16 m_touch_x_max;
   s16 m_touch_y_max;
+
+  const u32 m_client_uid;
 };
 
 using MathUtil::GRAVITY_ACCELERATION;
@@ -196,13 +198,34 @@ struct Server
   SteadyClock::time_point m_disconnect_time = SteadyClock::now();
 };
 
-static bool s_has_init;
+class InputBackend final : public ciface::InputBackend
-static bool s_servers_enabled;
+{
-static std::vector<Server> s_servers;
+public:
-static u32 s_client_uid;
+  InputBackend(ControllerInterface* controller_interface);
-static SteadyClock::time_point s_next_listports_time;
+  ~InputBackend();
-static std::thread s_hotplug_thread;
+  void PopulateDevices() override;
-static Common::Flag s_hotplug_thread_running;
+
+private:
+  void ConfigChanged();
+  void Restart();
+
+  void HotplugThreadFunc();
+  void StartHotplugThread();
+  void StopHotplugThread();
+
+  bool m_servers_enabled;
+  std::vector<Server> m_servers;
+  u32 m_client_uid;
+  SteadyClock::time_point m_next_listports_time;
+  std::thread m_hotplug_thread;
+  Common::Flag m_hotplug_thread_running;
+  std::size_t m_config_change_callback_id;
+};
+
+std::unique_ptr<ciface::InputBackend> CreateInputBackend(ControllerInterface* controller_interface)
+{
+  return std::make_unique<InputBackend>(controller_interface);
+}
 
 static bool IsSameController(const Proto::MessageType::PortInfo& a,
                              const Proto::MessageType::PortInfo& b)
@@ -212,29 +235,29 @@ static bool IsSameController(const Proto::MessageType::PortInfo& a,
          std::tie(b.pad_id, b.pad_state, b.model, b.connection_type, b.pad_mac_address);
 }
 
-static void HotplugThreadFunc()
+void InputBackend::HotplugThreadFunc()
 {
   Common::SetCurrentThreadName("DualShockUDPClient Hotplug Thread");
   INFO_LOG_FMT(CONTROLLERINTERFACE, "DualShockUDPClient hotplug thread started");
   Common::ScopeGuard thread_stop_guard{
       [] { INFO_LOG_FMT(CONTROLLERINTERFACE, "DualShockUDPClient hotplug thread stopped"); }};
 
-  std::vector<bool> timed_out_servers(s_servers.size(), false);
+  std::vector<bool> timed_out_servers(m_servers.size(), false);
 
-  while (s_hotplug_thread_running.IsSet())
+  while (m_hotplug_thread_running.IsSet())
   {
     using namespace std::chrono;
     using namespace std::chrono_literals;
 
     const auto now = SteadyClock::now();
-    if (now >= s_next_listports_time)
+    if (now >= m_next_listports_time)
     {
-      s_next_listports_time = now + SERVER_LISTPORTS_INTERVAL;
+      m_next_listports_time = now + SERVER_LISTPORTS_INTERVAL;
 
-      for (size_t i = 0; i < s_servers.size(); ++i)
+      for (size_t i = 0; i < m_servers.size(); ++i)
       {
-        auto& server = s_servers[i];
+        auto& server = m_servers[i];
-        Proto::Message<Proto::MessageType::ListPorts> msg(s_client_uid);
+        Proto::Message<Proto::MessageType::ListPorts> msg(m_client_uid);
         auto& list_ports = msg.m_message;
         // We ask for x possible devices. We will receive a message for every connected device.
         list_ports.pad_request_count = SERVER_ASKED_PADS;
@@ -250,12 +273,12 @@ static void HotplugThreadFunc()
     }
 
     sf::SocketSelector selector;
-    for (auto& server : s_servers)
+    for (auto& server : m_servers)
     {
       selector.add(server.m_socket);
     }
 
-    auto timeout = duration_cast<milliseconds>(s_next_listports_time - SteadyClock::now());
+    auto timeout = duration_cast<milliseconds>(m_next_listports_time - SteadyClock::now());
 
     // Receive controller port info within a time from our request.
     // Run this even if we sent no new requests, to disconnect devices,
@@ -271,9 +294,9 @@ static void HotplugThreadFunc()
       if (selector.wait(sf::milliseconds(current_timeout.count())))
       {
         // Now check all the servers because we don't know which one(s) sent a reply
-        for (size_t i = 0; i < s_servers.size(); ++i)
+        for (size_t i = 0; i < m_servers.size(); ++i)
         {
-          auto& server = s_servers[i];
+          auto& server = m_servers[i];
           if (!selector.isReady(server.m_socket))
           {
             continue;
@@ -302,20 +325,20 @@ static void HotplugThreadFunc()
             {
               server.m_port_info[port_info->pad_id] = *port_info;
               // Just remove and re-add all the devices for simplicity
-              g_controller_interface.PlatformPopulateDevices([] { PopulateDevices(); });
+              GetControllerInterface().PlatformPopulateDevices([this] { PopulateDevices(); });
             }
           }
         }
       }
-      if (!s_hotplug_thread_running.IsSet())  // Avoid hanging the thread for too long
+      if (!m_hotplug_thread_running.IsSet())  // Avoid hanging the thread for too long
         return;
     } while (timeout > 0ms);
 
     // If we have failed to receive any information from the server (or even send it),
     // disconnect all devices from it (after enough time has elapsed, to avoid false positives).
-    for (size_t i = 0; i < s_servers.size(); ++i)
+    for (size_t i = 0; i < m_servers.size(); ++i)
     {
-      auto& server = s_servers[i];
+      auto& server = m_servers[i];
       if (timed_out_servers[i] && SteadyClock::now() >= server.m_disconnect_time)
       {
         bool any_connected = false;
@@ -328,49 +351,49 @@ static void HotplugThreadFunc()
         }
         // We can't only remove devices added by this server as we wouldn't know which they are
         if (any_connected)
-          g_controller_interface.PlatformPopulateDevices([] { PopulateDevices(); });
+          GetControllerInterface().PlatformPopulateDevices([this] { PopulateDevices(); });
       }
     }
   }
 }
 
-static void StartHotplugThread()
+void InputBackend::StartHotplugThread()
 {
   // Mark the thread as running.
-  if (!s_hotplug_thread_running.TestAndSet())
+  if (!m_hotplug_thread_running.TestAndSet())
   {
     // It was already running.
     return;
   }
 
-  s_hotplug_thread = std::thread(HotplugThreadFunc);
+  m_hotplug_thread = std::thread(&InputBackend::HotplugThreadFunc, this);
 }
 
-static void StopHotplugThread()
+void InputBackend::StopHotplugThread()
 {
   // Tell the hotplug thread to stop.
-  if (!s_hotplug_thread_running.TestAndClear())
+  if (!m_hotplug_thread_running.TestAndClear())
   {
     // It wasn't running, we're done.
     return;
   }
 
-  s_hotplug_thread.join();
+  m_hotplug_thread.join();
 
-  for (auto& server : s_servers)
+  for (auto& server : m_servers)
   {
     server.m_socket.unbind();  // interrupt blocking socket
   }
 }
 
 // Also just start
-static void Restart()
+void InputBackend::Restart()
 {
   INFO_LOG_FMT(CONTROLLERINTERFACE, "DualShockUDPClient Restart");
 
   StopHotplugThread();
 
-  for (auto& server : s_servers)
+  for (auto& server : m_servers)
   {
     for (size_t port_index = 0; port_index < server.m_port_info.size(); port_index++)
     {
@@ -380,37 +403,34 @@ static void Restart()
   }
 
   // Only removes devices as servers have been cleaned
-  g_controller_interface.PlatformPopulateDevices([] { PopulateDevices(); });
+  GetControllerInterface().PlatformPopulateDevices([this] { PopulateDevices(); });
 
-  s_client_uid = Common::Random::GenerateValue<u32>();
+  m_client_uid = Common::Random::GenerateValue<u32>();
-  s_next_listports_time = SteadyClock::now();
+  m_next_listports_time = SteadyClock::now();
 
-  if (s_servers_enabled && !s_servers.empty())
+  if (m_servers_enabled && !m_servers.empty())
     StartHotplugThread();
 }
 
-static void ConfigChanged()
+void InputBackend::ConfigChanged()
 {
-  if (!s_has_init)
-    return;
-
   const bool servers_enabled = Config::Get(Settings::SERVERS_ENABLED);
   const std::string servers_setting = Config::Get(Settings::SERVERS);
 
   std::string new_servers_setting;
-  for (const auto& server : s_servers)
+  for (const auto& server : m_servers)
   {
     new_servers_setting +=
         fmt::format("{}:{}:{};", server.m_description, server.m_address, server.m_port);
   }
 
-  if (servers_enabled != s_servers_enabled || servers_setting != new_servers_setting)
+  if (servers_enabled != m_servers_enabled || servers_setting != new_servers_setting)
   {
-    // Stop the thread before writing to s_servers
+    // Stop the thread before writing to m_servers
     StopHotplugThread();
 
-    s_servers_enabled = servers_enabled;
+    m_servers_enabled = servers_enabled;
-    s_servers.clear();
+    m_servers.clear();
 
     const auto server_details = SplitString(servers_setting, ';');
     for (const auto& server_detail : server_details)
@@ -428,17 +448,15 @@ static void ConfigChanged()
       }
       u16 server_port = static_cast<u16>(port);
 
-      s_servers.emplace_back(description, server_address, server_port);
+      m_servers.emplace_back(description, server_address, server_port);
     }
     Restart();
   }
 }
 
-void Init()
+InputBackend::InputBackend(ControllerInterface* controller_interface)
+    : ciface::InputBackend(controller_interface)
 {
-  // Does not support multiple init calls
-  s_has_init = true;
-
   // The following is added for backwards compatibility
   const auto server_address_setting = Config::Get(Settings::SERVER_ADDRESS);
   const auto server_port_setting = Config::Get(Settings::SERVER_PORT);
@@ -454,29 +472,30 @@ void Init()
     Config::SetBase(Settings::SERVER_PORT, 0);
   }
 
-  // It would be much better to unbind from this callback on DeInit but it's not possible as of now
+  m_config_change_callback_id =
-  Config::AddConfigChangedCallback(ConfigChanged);
+      Config::AddConfigChangedCallback(std::bind(&InputBackend::ConfigChanged, this));
-  ConfigChanged();  // Call it immediately to load settings
+  // Call it immediately to load settings
+  ConfigChanged();
 }
 
 // This can be called by the host thread as well as the hotplug thread, concurrently.
 // So use PlatformPopulateDevices().
-// s_servers is already safe because it can only be modified when the DSU thread is not running,
+// m_servers is already safe because it can only be modified when the DSU thread is not running,
 // from the main thread
-void PopulateDevices()
+void InputBackend::PopulateDevices()
 {
   INFO_LOG_FMT(CONTROLLERINTERFACE, "DualShockUDPClient PopulateDevices");
 
-  // s_servers has already been updated so we can't use it to know which devices we removed,
+  // m_servers has already been updated so we can't use it to know which devices we removed,
   // also it's good to remove all of them before adding new ones so that their id will be set
   // correctly if they have the same name
-  g_controller_interface.RemoveDevice(
+  GetControllerInterface().RemoveDevice(
       [](const auto* dev) { return dev->GetSource() == DUALSHOCKUDP_SOURCE_NAME; });
 
   // Users might have created more than one server on the same IP/Port.
   // Devices might end up being duplicated (if the server responds two all requests)
   // but they won't conflict.
-  for (const auto& server : s_servers)
+  for (const auto& server : m_servers)
   {
     for (size_t port_index = 0; port_index < server.m_port_info.size(); port_index++)
     {
@@ -484,24 +503,23 @@ void PopulateDevices()
       if (port_info.pad_state != Proto::DsState::Connected)
         continue;
 
-      g_controller_interface.AddDevice(std::make_shared<Device>(
+      GetControllerInterface().AddDevice(
-          server.m_description, static_cast<int>(port_index), server.m_address, server.m_port));
+          std::make_shared<Device>(server.m_description, static_cast<int>(port_index),
+                                   server.m_address, server.m_port, m_client_uid));
     }
   }
 }
 
-void DeInit()
+InputBackend::~InputBackend()
 {
+  Config::RemoveConfigChangedCallback(m_config_change_callback_id);
   StopHotplugThread();
-
-  s_has_init = false;
-  s_servers_enabled = false;
-  s_servers.clear();
 }
 
-Device::Device(std::string name, int index, std::string server_address, u16 server_port)
+Device::Device(std::string name, int index, std::string server_address, u16 server_port,
+               u32 client_uid)
     : m_name{std::move(name)}, m_index{index}, m_server_address{std::move(server_address)},
-      m_server_port{server_port}
+      m_server_port{server_port}, m_client_uid(client_uid)
 {
   m_socket.setBlocking(false);
 
@@ -604,7 +622,7 @@ void Device::UpdateInput()
   {
     m_next_reregister = now + SERVER_REREGISTER_INTERVAL;
 
-    Proto::Message<Proto::MessageType::PadDataRequest> msg(s_client_uid);
+    Proto::Message<Proto::MessageType::PadDataRequest> msg(m_client_uid);
     auto& data_req = msg.m_message;
     data_req.register_flags = Proto::RegisterFlags::PadID;
     data_req.pad_id_to_register = m_index;

Source/Core/InputCommon/ControllerInterface/DualShockUDPClient/DualShockUDPClient.h

@@ -4,6 +4,7 @@
 #pragma once
 
 #include "Common/Config/Config.h"
+#include "InputCommon/ControllerInterface/InputBackend.h"
 
 namespace ciface::DualShockUDPClient
 {
@@ -20,7 +21,6 @@ extern const Config::Info<std::string> SERVERS;
 extern const Config::Info<bool> SERVERS_ENABLED;
 }  // namespace Settings
 
-void Init();
+std::unique_ptr<ciface::InputBackend> CreateInputBackend(ControllerInterface* controller_interface);
-void PopulateDevices();
+
-void DeInit();
 }  // namespace ciface::DualShockUDPClient

Source/Core/InputCommon/ControllerInterface/InputBackend.cpp

@@ -0,0 +1,24 @@
+// Copyright 2022 Dolphin Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "InputCommon/ControllerInterface/InputBackend.h"
+
+namespace ciface
+{
+InputBackend::InputBackend(ControllerInterface* controller_interface)
+    : m_controller_interface(*controller_interface)
+{
+}
+
+InputBackend::~InputBackend() = default;
+
+void InputBackend::UpdateInput()
+{
+}
+
+ControllerInterface& InputBackend::GetControllerInterface()
+{
+  return m_controller_interface;
+}
+
+}  // namespace ciface

Source/Core/InputCommon/ControllerInterface/InputBackend.h

@@ -0,0 +1,26 @@
+// Copyright 2022 Dolphin Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+class ControllerInterface;
+
+namespace ciface
+{
+class InputBackend
+{
+public:
+  InputBackend(ControllerInterface* controller_interface);
+
+  virtual ~InputBackend();
+
+  virtual void PopulateDevices() = 0;
+  virtual void UpdateInput();
+
+  ControllerInterface& GetControllerInterface();
+
+private:
+  ControllerInterface& m_controller_interface;
+};
+
+}  // namespace ciface

Source/Core/InputCommon/ControllerInterface/SDL/SDL.cpp

@@ -29,7 +29,33 @@ static std::string GetJoystickName(int index)
 #endif
 }
 
-static void OpenAndAddDevice(int index)
+class InputBackend final : public ciface::InputBackend
+{
+public:
+  InputBackend(ControllerInterface* controller_interface);
+  ~InputBackend();
+  void PopulateDevices() override;
+  void UpdateInput() override;
+
+private:
+  void OpenAndAddDevice(int index);
+
+#if SDL_VERSION_ATLEAST(2, 0, 0)
+  bool HandleEventAndContinue(const SDL_Event& e);
+
+  Common::Event m_init_event;
+  Uint32 m_stop_event_type;
+  Uint32 m_populate_event_type;
+  std::thread m_hotplug_thread;
+#endif
+};
+
+std::unique_ptr<ciface::InputBackend> CreateInputBackend(ControllerInterface* controller_interface)
+{
+  return std::make_unique<InputBackend>(controller_interface);
+}
+
+void InputBackend::OpenAndAddDevice(int index)
 {
   SDL_Joystick* const dev = SDL_JoystickOpen(index);
   if (dev)
@@ -37,17 +63,13 @@ static void OpenAndAddDevice(int index)
     auto js = std::make_shared<Joystick>(dev, index);
     // only add if it has some inputs/outputs
     if (!js->Inputs().empty() || !js->Outputs().empty())
-      g_controller_interface.AddDevice(std::move(js));
+      GetControllerInterface().AddDevice(std::move(js));
   }
 }
 
 #if SDL_VERSION_ATLEAST(2, 0, 0)
-static Common::Event s_init_event;
-static Uint32 s_stop_event_type;
-static Uint32 s_populate_event_type;
-static std::thread s_hotplug_thread;
 
-static bool HandleEventAndContinue(const SDL_Event& e)
+bool InputBackend::HandleEventAndContinue(const SDL_Event& e)
 {
   if (e.type == SDL_JOYDEVICEADDED)
   {
@@ -55,20 +77,20 @@ static bool HandleEventAndContinue(const SDL_Event& e)
   }
   else if (e.type == SDL_JOYDEVICEREMOVED)
   {
-    g_controller_interface.RemoveDevice([&e](const auto* device) {
+    GetControllerInterface().RemoveDevice([&e](const auto* device) {
       return device->GetSource() == "SDL" &&
              SDL_JoystickInstanceID(static_cast<const Joystick*>(device)->GetSDLJoystick()) ==
                  e.jdevice.which;
     });
   }
-  else if (e.type == s_populate_event_type)
+  else if (e.type == m_populate_event_type)
   {
-    g_controller_interface.PlatformPopulateDevices([] {
+    GetControllerInterface().PlatformPopulateDevices([this] {
       for (int i = 0; i < SDL_NumJoysticks(); ++i)
         OpenAndAddDevice(i);
     });
   }
-  else if (e.type == s_stop_event_type)
+  else if (e.type == m_stop_event_type)
   {
     return false;
   }
@@ -144,7 +166,8 @@ static void EnableSDLLogging()
       nullptr);
 }
 
-void Init()
+InputBackend::InputBackend(ControllerInterface* controller_interface)
+    : ciface::InputBackend(controller_interface)
 {
 #if !SDL_VERSION_ATLEAST(2, 0, 0)
   if (SDL_Init(SDL_INIT_JOYSTICK | SDL_INIT_HAPTIC) != 0)
@@ -168,13 +191,13 @@ void Init()
   SDL_SetHint(SDL_HINT_JOYSTICK_HIDAPI_PS4_RUMBLE, "1");
 #endif
 
-  s_hotplug_thread = std::thread([] {
+  m_hotplug_thread = std::thread([this] {
     Common::ScopeGuard quit_guard([] {
       // TODO: there seems to be some sort of memory leak with SDL, quit isn't freeing everything up
       SDL_Quit();
     });
     {
-      Common::ScopeGuard init_guard([] { s_init_event.Set(); });
+      Common::ScopeGuard init_guard([this] { m_init_event.Set(); });
 
       if (SDL_Init(SDL_INIT_JOYSTICK | SDL_INIT_HAPTIC | SDL_INIT_GAMECONTROLLER) != 0)
       {
@@ -188,8 +211,8 @@ void Init()
         ERROR_LOG_FMT(CONTROLLERINTERFACE, "SDL failed to register custom events");
         return;
       }
-      s_stop_event_type = custom_events_start;
+      m_stop_event_type = custom_events_start;
-      s_populate_event_type = custom_events_start + 1;
+      m_populate_event_type = custom_events_start + 1;
 
       // Drain all of the events and add the initial joysticks before returning. Otherwise, the
       // individual joystick events as well as the custom populate event will be handled _after_
@@ -235,26 +258,26 @@ void Init()
     }
   });
 
-  s_init_event.Wait();
+  m_init_event.Wait();
 #endif
 }
 
-void DeInit()
+InputBackend::~InputBackend()
 {
 #if !SDL_VERSION_ATLEAST(2, 0, 0)
   SDL_Quit();
 #else
-  if (!s_hotplug_thread.joinable())
+  if (!m_hotplug_thread.joinable())
     return;
 
-  SDL_Event stop_event{s_stop_event_type};
+  SDL_Event stop_event{m_stop_event_type};
   SDL_PushEvent(&stop_event);
 
-  s_hotplug_thread.join();
+  m_hotplug_thread.join();
 #endif
 }
 
-void PopulateDevices()
+void InputBackend::PopulateDevices()
 {
 #if !SDL_VERSION_ATLEAST(2, 0, 0)
   if (!SDL_WasInit(SDL_INIT_JOYSTICK))
@@ -263,10 +286,10 @@ void PopulateDevices()
   for (int i = 0; i < SDL_NumJoysticks(); ++i)
     OpenAndAddDevice(i);
 #else
-  if (!s_hotplug_thread.joinable())
+  if (!m_hotplug_thread.joinable())
     return;
 
-  SDL_Event populate_event{s_populate_event_type};
+  SDL_Event populate_event{m_populate_event_type};
   SDL_PushEvent(&populate_event);
 #endif
 }
@@ -617,9 +640,8 @@ void Joystick::Motor::SetState(ControlState state)
 }
 #endif
 
-void Joystick::UpdateInput()
+void InputBackend::UpdateInput()
 {
-  // TODO: Don't call this for every Joystick, only once per ControllerInterface::UpdateInput()
   SDL_JoystickUpdate();
 }
 

Source/Core/InputCommon/ControllerInterface/SDL/SDL.h

@@ -22,12 +22,11 @@
 #endif
 
 #include "InputCommon/ControllerInterface/CoreDevice.h"
+#include "InputCommon/ControllerInterface/InputBackend.h"
 
 namespace ciface::SDL
 {
-void Init();
+std::unique_ptr<ciface::InputBackend> CreateInputBackend(ControllerInterface* controller_interface);
-void DeInit();
-void PopulateDevices();
 
 class Joystick : public Core::Device
 {
@@ -182,8 +181,6 @@ private:
 #endif
 
 public:
-  void UpdateInput() override;
-
   Joystick(SDL_Joystick* const joystick, const int sdl_index);
   ~Joystick();
 

Source/Core/InputCommon/ControllerInterface/evdev/evdev.cpp

@@ -25,6 +25,43 @@
 
 namespace ciface::evdev
 {
+class InputBackend final : public ciface::InputBackend
+{
+public:
+  InputBackend(ControllerInterface* controller_interface);
+  ~InputBackend();
+  void PopulateDevices() override;
+
+  void RemoveDevnodeObject(const std::string&);
+
+private:
+  std::shared_ptr<evdevDevice>
+  FindDeviceWithUniqueIDAndPhysicalLocation(const char* unique_id, const char* physical_location);
+
+  void AddDeviceNode(const char* devnode);
+
+  void StartHotplugThread();
+  void StopHotplugThread();
+  void HotplugThreadFunc();
+
+  std::thread m_hotplug_thread;
+  Common::Flag m_hotplug_thread_running;
+  int m_wakeup_eventfd;
+
+  // There is no easy way to get the device name from only a dev node
+  // during a device removed event, since libevdev can't work on removed devices;
+  // sysfs is not stable, so this is probably the easiest way to get a name for a node.
+  // This can, and will be modified by different thread, possibly concurrently,
+  // as devices can be destroyed by any thread at any time. As of now it's protected
+  // by ControllerInterface::m_devices_population_mutex.
+  std::map<std::string, std::weak_ptr<evdevDevice>> m_devnode_objects;
+};
+
+std::unique_ptr<ciface::InputBackend> CreateInputBackend(ControllerInterface* controller_interface)
+{
+  return std::make_unique<InputBackend>(controller_interface);
+}
+
 class Input : public Core::Device::Input
 {
 public:
@@ -195,25 +232,14 @@ public:
   bool IsDetectable() const override { return false; }
 };
 
-static std::thread s_hotplug_thread;
+std::shared_ptr<evdevDevice>
-static Common::Flag s_hotplug_thread_running;
+InputBackend::FindDeviceWithUniqueIDAndPhysicalLocation(const char* unique_id,
-static int s_wakeup_eventfd;
+                                                        const char* physical_location)
-
-// There is no easy way to get the device name from only a dev node
-// during a device removed event, since libevdev can't work on removed devices;
-// sysfs is not stable, so this is probably the easiest way to get a name for a node.
-// This can, and will be modified by different thread, possibly concurrently,
-// as devices can be destroyed by any thread at any time. As of now it's protected
-// by ControllerInterface::m_devices_population_mutex.
-static std::map<std::string, std::weak_ptr<evdevDevice>> s_devnode_objects;
-
-static std::shared_ptr<evdevDevice>
-FindDeviceWithUniqueIDAndPhysicalLocation(const char* unique_id, const char* physical_location)
 {
   if (!unique_id || !physical_location)
     return nullptr;
 
-  for (auto& [node, dev] : s_devnode_objects)
+  for (auto& [node, dev] : m_devnode_objects)
   {
     if (const auto device = dev.lock())
     {
@@ -231,7 +257,7 @@ FindDeviceWithUniqueIDAndPhysicalLocation(const char* unique_id, const char* phy
   return nullptr;
 }
 
-static void AddDeviceNode(const char* devnode)
+void InputBackend::AddDeviceNode(const char* devnode)
 {
   // Unfortunately udev gives us no way to filter out the non event device interfaces.
   // So we open it and see if it works with evdev ioctls or not.
@@ -265,30 +291,30 @@ static void AddDeviceNode(const char* devnode)
     // This will also give it the correct index and invoke device change callbacks.
     // Make sure to force the device removal immediately (as they are shared ptrs and
     // they could be kept alive, preventing us from re-creating the device)
-    g_controller_interface.RemoveDevice(
+    GetControllerInterface().RemoveDevice(
         [&evdev_device](const auto* device) {
           return static_cast<const evdevDevice*>(device) == evdev_device.get();
         },
         true);
 
-    g_controller_interface.AddDevice(evdev_device);
+    GetControllerInterface().AddDevice(evdev_device);
   }
   else
   {
-    evdev_device = std::make_shared<evdevDevice>();
+    evdev_device = std::make_shared<evdevDevice>(this);
 
     const bool was_interesting = evdev_device->AddNode(devnode, fd, dev);
 
     if (was_interesting)
-      g_controller_interface.AddDevice(evdev_device);
+      GetControllerInterface().AddDevice(evdev_device);
   }
 
-  // If the devices failed to be added to g_controller_interface, it will be added here but then
+  // If the devices failed to be added to ControllerInterface, it will be added here but then
   // immediately removed in its destructor due to the shared ptr not having any references left
-  s_devnode_objects.emplace(devnode, std::move(evdev_device));
+  m_devnode_objects.emplace(devnode, std::move(evdev_device));
 }
 
-static void HotplugThreadFunc()
+void InputBackend::HotplugThreadFunc()
 {
   Common::SetCurrentThreadName("evdev Hotplug Thread");
   NOTICE_LOG_FMT(CONTROLLERINTERFACE, "evdev hotplug thread started");
@@ -306,16 +332,16 @@ static void HotplugThreadFunc()
   udev_monitor_enable_receiving(monitor);
   const int monitor_fd = udev_monitor_get_fd(monitor);
 
-  while (s_hotplug_thread_running.IsSet())
+  while (m_hotplug_thread_running.IsSet())
   {
     fd_set fds;
 
     FD_ZERO(&fds);
     FD_SET(monitor_fd, &fds);
-    FD_SET(s_wakeup_eventfd, &fds);
+    FD_SET(m_wakeup_eventfd, &fds);
 
     const int ret =
-        select(std::max(monitor_fd, s_wakeup_eventfd) + 1, &fds, nullptr, nullptr, nullptr);
+        select(std::max(monitor_fd, m_wakeup_eventfd) + 1, &fds, nullptr, nullptr, nullptr);
     if (ret < 1 || !FD_ISSET(monitor_fd, &fds))
       continue;
 
@@ -327,53 +353,54 @@ static void HotplugThreadFunc()
     if (!devnode)
       continue;
 
-    // Use g_controller_interface.PlatformPopulateDevices() to protect access around
+    // Use GetControllerInterface().PlatformPopulateDevices() to protect access around
-    // s_devnode_objects. Note that even if we get these events at the same time as a
+    // m_devnode_objects. Note that even if we get these events at the same time as a
     // a PopulateDevices() request (e.g. on start up, we might get all the add events
     // for connected devices), this won't ever cause duplicate devices as AddDeviceNode()
     // automatically removes the old one if it already existed
     if (strcmp(action, "remove") == 0)
     {
-      g_controller_interface.PlatformPopulateDevices([&devnode] {
+      GetControllerInterface().PlatformPopulateDevices([&devnode, this] {
         std::shared_ptr<evdevDevice> ptr;
 
-        const auto it = s_devnode_objects.find(devnode);
+        const auto it = m_devnode_objects.find(devnode);
-        if (it != s_devnode_objects.end())
+        if (it != m_devnode_objects.end())
           ptr = it->second.lock();
 
         // If we don't recognize this device, ptr will be null and no device will be removed.
 
-        g_controller_interface.RemoveDevice([&ptr](const auto* device) {
+        GetControllerInterface().RemoveDevice([&ptr](const auto* device) {
           return static_cast<const evdevDevice*>(device) == ptr.get();
         });
       });
     }
     else if (strcmp(action, "add") == 0)
     {
-      g_controller_interface.PlatformPopulateDevices([&devnode] { AddDeviceNode(devnode); });
+      GetControllerInterface().PlatformPopulateDevices(
+          [&devnode, this] { AddDeviceNode(devnode); });
     }
   }
   NOTICE_LOG_FMT(CONTROLLERINTERFACE, "evdev hotplug thread stopped");
 }
 
-static void StartHotplugThread()
+void InputBackend::StartHotplugThread()
 {
   // Mark the thread as running.
-  if (!s_hotplug_thread_running.TestAndSet())
+  if (!m_hotplug_thread_running.TestAndSet())
   {
     // It was already running.
     return;
   }
 
-  s_wakeup_eventfd = eventfd(0, 0);
+  m_wakeup_eventfd = eventfd(0, 0);
-  ASSERT_MSG(CONTROLLERINTERFACE, s_wakeup_eventfd != -1, "Couldn't create eventfd.");
+  ASSERT_MSG(CONTROLLERINTERFACE, m_wakeup_eventfd != -1, "Couldn't create eventfd.");
-  s_hotplug_thread = std::thread(HotplugThreadFunc);
+  m_hotplug_thread = std::thread(&InputBackend::HotplugThreadFunc, this);
 }
 
-static void StopHotplugThread()
+void InputBackend::StopHotplugThread()
 {
   // Tell the hotplug thread to stop.
-  if (!s_hotplug_thread_running.TestAndClear())
+  if (!m_hotplug_thread_running.TestAndClear())
   {
     // It wasn't running, we're done.
     return;
@@ -381,22 +408,23 @@ static void StopHotplugThread()
 
   // Write something to efd so that select() stops blocking.
   const uint64_t value = 1;
-  static_cast<void>(!write(s_wakeup_eventfd, &value, sizeof(uint64_t)));
+  static_cast<void>(!write(m_wakeup_eventfd, &value, sizeof(uint64_t)));
 
-  s_hotplug_thread.join();
+  m_hotplug_thread.join();
-  close(s_wakeup_eventfd);
+  close(m_wakeup_eventfd);
 }
 
-void Init()
+InputBackend::InputBackend(ControllerInterface* controller_interface)
+    : ciface::InputBackend(controller_interface)
 {
   StartHotplugThread();
 }
 
 // Only call this when ControllerInterface::m_devices_population_mutex is locked
-void PopulateDevices()
+void InputBackend::PopulateDevices()
 {
   // Don't run if we are not initialized
-  if (!s_hotplug_thread_running.IsSet())
+  if (!m_hotplug_thread_running.IsSet())
   {
     return;
   }
@@ -431,7 +459,7 @@ void PopulateDevices()
   udev_unref(udev);
 }
 
-void Shutdown()
+InputBackend::~InputBackend()
 {
   StopHotplugThread();
 }
@@ -627,16 +655,25 @@ const char* evdevDevice::GetPhysicalLocation() const
   return libevdev_get_phys(m_nodes.front().device);
 }
 
+evdevDevice::evdevDevice(InputBackend* input_backend) : m_input_backend(*input_backend)
+{
+}
+
 evdevDevice::~evdevDevice()
 {
   for (auto& node : m_nodes)
   {
-    s_devnode_objects.erase(node.devnode);
+    m_input_backend.RemoveDevnodeObject(node.devnode);
     libevdev_free(node.device);
     close(node.fd);
   }
 }
 
+void InputBackend::RemoveDevnodeObject(const std::string& node)
+{
+  m_devnode_objects.erase(node);
+}
+
 void evdevDevice::UpdateInput()
 {
   // Run through all evdev events

Source/Core/InputCommon/ControllerInterface/evdev/evdev.h

@@ -11,9 +11,9 @@
 
 namespace ciface::evdev
 {
-void Init();
+class InputBackend;
-void PopulateDevices();
+
-void Shutdown();
+std::unique_ptr<ciface::InputBackend> CreateInputBackend(ControllerInterface* controller_interface);
 
 class evdevDevice : public Core::Device
 {
@@ -75,6 +75,7 @@ public:
   void UpdateInput() override;
   bool IsValid() const override;
 
+  evdevDevice(InputBackend* input_backend);
   ~evdevDevice();
 
   // Return true if node was "interesting".
@@ -97,5 +98,7 @@ private:
   };
 
   std::vector<Node> m_nodes;
+
+  InputBackend& m_input_backend;
 };
 }  // namespace ciface::evdev