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-rw-r--r--src/input_common/sdl/sdl_impl.cpp629
-rw-r--r--src/input_common/sdl/sdl_impl.h51
2 files changed, 680 insertions, 0 deletions
diff --git a/src/input_common/sdl/sdl_impl.cpp b/src/input_common/sdl/sdl_impl.cpp
new file mode 100644
index 000000000..7c1ecc2e0
--- /dev/null
+++ b/src/input_common/sdl/sdl_impl.cpp
@@ -0,0 +1,629 @@
+// Copyright 2017 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <algorithm>
+#include <atomic>
+#include <cmath>
+#include <functional>
+#include <iterator>
+#include <mutex>
+#include <string>
+#include <thread>
+#include <tuple>
+#include <unordered_map>
+#include <utility>
+#include <vector>
+#include <SDL.h>
+#include "common/assert.h"
+#include "common/logging/log.h"
+#include "common/math_util.h"
+#include "common/param_package.h"
+#include "common/threadsafe_queue.h"
+#include "input_common/main.h"
+#include "input_common/sdl/sdl.h"
+
+namespace InputCommon {
+
+namespace SDL {
+
+class SDLJoystick;
+class SDLButtonFactory;
+class SDLAnalogFactory;
+
+/// Map of GUID of a list of corresponding virtual Joysticks
+static std::unordered_map<std::string, std::vector<std::shared_ptr<SDLJoystick>>> joystick_map;
+static std::mutex joystick_map_mutex;
+
+static std::shared_ptr<SDLButtonFactory> button_factory;
+static std::shared_ptr<SDLAnalogFactory> analog_factory;
+
+/// Used by the Pollers during config
+static std::atomic<bool> polling;
+static Common::SPSCQueue<SDL_Event> event_queue;
+
+static std::atomic<bool> initialized = false;
+
+static std::string GetGUID(SDL_Joystick* joystick) {
+ SDL_JoystickGUID guid = SDL_JoystickGetGUID(joystick);
+ char guid_str[33];
+ SDL_JoystickGetGUIDString(guid, guid_str, sizeof(guid_str));
+ return guid_str;
+}
+
+class SDLJoystick {
+public:
+ SDLJoystick(std::string guid_, int port_, SDL_Joystick* joystick,
+ decltype(&SDL_JoystickClose) deleter = &SDL_JoystickClose)
+ : guid{std::move(guid_)}, port{port_}, sdl_joystick{joystick, deleter} {}
+
+ void SetButton(int button, bool value) {
+ std::lock_guard<std::mutex> lock(mutex);
+ state.buttons[button] = value;
+ }
+
+ bool GetButton(int button) const {
+ std::lock_guard<std::mutex> lock(mutex);
+ return state.buttons.at(button);
+ }
+
+ void SetAxis(int axis, Sint16 value) {
+ std::lock_guard<std::mutex> lock(mutex);
+ state.axes[axis] = value;
+ }
+
+ float GetAxis(int axis) const {
+ std::lock_guard<std::mutex> lock(mutex);
+ return state.axes.at(axis) / 32767.0f;
+ }
+
+ std::tuple<float, float> GetAnalog(int axis_x, int axis_y) const {
+ float x = GetAxis(axis_x);
+ float y = GetAxis(axis_y);
+ y = -y; // 3DS uses an y-axis inverse from SDL
+
+ // Make sure the coordinates are in the unit circle,
+ // otherwise normalize it.
+ float r = x * x + y * y;
+ if (r > 1.0f) {
+ r = std::sqrt(r);
+ x /= r;
+ y /= r;
+ }
+
+ return std::make_tuple(x, y);
+ }
+
+ void SetHat(int hat, Uint8 direction) {
+ std::lock_guard<std::mutex> lock(mutex);
+ state.hats[hat] = direction;
+ }
+
+ bool GetHatDirection(int hat, Uint8 direction) const {
+ std::lock_guard<std::mutex> lock(mutex);
+ return (state.hats.at(hat) & direction) != 0;
+ }
+ /**
+ * The guid of the joystick
+ */
+ const std::string& GetGUID() const {
+ return guid;
+ }
+
+ /**
+ * The number of joystick from the same type that were connected before this joystick
+ */
+ int GetPort() const {
+ return port;
+ }
+
+ SDL_Joystick* GetSDLJoystick() const {
+ return sdl_joystick.get();
+ }
+
+ void SetSDLJoystick(SDL_Joystick* joystick,
+ decltype(&SDL_JoystickClose) deleter = &SDL_JoystickClose) {
+ sdl_joystick =
+ std::unique_ptr<SDL_Joystick, decltype(&SDL_JoystickClose)>(joystick, deleter);
+ }
+
+private:
+ struct State {
+ std::unordered_map<int, bool> buttons;
+ std::unordered_map<int, Sint16> axes;
+ std::unordered_map<int, Uint8> hats;
+ } state;
+ std::string guid;
+ int port;
+ std::unique_ptr<SDL_Joystick, decltype(&SDL_JoystickClose)> sdl_joystick;
+ mutable std::mutex mutex;
+};
+
+/**
+ * Get the nth joystick with the corresponding GUID
+ */
+static std::shared_ptr<SDLJoystick> GetSDLJoystickByGUID(const std::string& guid, int port) {
+ std::lock_guard<std::mutex> lock(joystick_map_mutex);
+ const auto it = joystick_map.find(guid);
+ if (it != joystick_map.end()) {
+ while (it->second.size() <= port) {
+ auto joystick = std::make_shared<SDLJoystick>(guid, it->second.size(), nullptr,
+ [](SDL_Joystick*) {});
+ it->second.emplace_back(std::move(joystick));
+ }
+ return it->second[port];
+ }
+ auto joystick = std::make_shared<SDLJoystick>(guid, 0, nullptr, [](SDL_Joystick*) {});
+ return joystick_map[guid].emplace_back(std::move(joystick));
+}
+
+/**
+ * Check how many identical joysticks (by guid) were connected before the one with sdl_id and so tie
+ * it to a SDLJoystick with the same guid and that port
+ */
+static std::shared_ptr<SDLJoystick> GetSDLJoystickBySDLID(SDL_JoystickID sdl_id) {
+ std::lock_guard<std::mutex> lock(joystick_map_mutex);
+ auto sdl_joystick = SDL_JoystickFromInstanceID(sdl_id);
+ const std::string guid = GetGUID(sdl_joystick);
+ auto map_it = joystick_map.find(guid);
+ if (map_it != joystick_map.end()) {
+ auto vec_it = std::find_if(map_it->second.begin(), map_it->second.end(),
+ [&sdl_joystick](const std::shared_ptr<SDLJoystick>& joystick) {
+ return sdl_joystick == joystick->GetSDLJoystick();
+ });
+ if (vec_it != map_it->second.end()) {
+ // This is the common case: There is already an existing SDL_Joystick maped to a
+ // SDLJoystick. return the SDLJoystick
+ return *vec_it;
+ }
+ // Search for a SDLJoystick without a mapped SDL_Joystick...
+ auto nullptr_it = std::find_if(map_it->second.begin(), map_it->second.end(),
+ [](const std::shared_ptr<SDLJoystick>& joystick) {
+ return !joystick->GetSDLJoystick();
+ });
+ if (nullptr_it != map_it->second.end()) {
+ // ... and map it
+ (*nullptr_it)->SetSDLJoystick(sdl_joystick);
+ return *nullptr_it;
+ }
+ // There is no SDLJoystick without a mapped SDL_Joystick
+ // Create a new SDLJoystick
+ auto joystick = std::make_shared<SDLJoystick>(guid, map_it->second.size(), sdl_joystick);
+ return map_it->second.emplace_back(std::move(joystick));
+ }
+ auto joystick = std::make_shared<SDLJoystick>(guid, 0, sdl_joystick);
+ return joystick_map[guid].emplace_back(std::move(joystick));
+}
+
+void InitJoystick(int joystick_index) {
+ std::lock_guard<std::mutex> lock(joystick_map_mutex);
+ SDL_Joystick* sdl_joystick = SDL_JoystickOpen(joystick_index);
+ if (!sdl_joystick) {
+ LOG_ERROR(Input, "failed to open joystick {}", joystick_index);
+ return;
+ }
+ std::string guid = GetGUID(sdl_joystick);
+ if (joystick_map.find(guid) == joystick_map.end()) {
+ auto joystick = std::make_shared<SDLJoystick>(guid, 0, sdl_joystick);
+ joystick_map[guid].emplace_back(std::move(joystick));
+ return;
+ }
+ auto& joystick_guid_list = joystick_map[guid];
+ const auto it = std::find_if(
+ joystick_guid_list.begin(), joystick_guid_list.end(),
+ [](const std::shared_ptr<SDLJoystick>& joystick) { return !joystick->GetSDLJoystick(); });
+ if (it != joystick_guid_list.end()) {
+ (*it)->SetSDLJoystick(sdl_joystick);
+ return;
+ }
+ auto joystick = std::make_shared<SDLJoystick>(guid, joystick_guid_list.size(), sdl_joystick);
+ joystick_guid_list.emplace_back(std::move(joystick));
+}
+
+void CloseJoystick(SDL_Joystick* sdl_joystick) {
+ std::lock_guard<std::mutex> lock(joystick_map_mutex);
+ std::string guid = GetGUID(sdl_joystick);
+ // This call to guid is save since the joystick is guranteed to be in that map
+ auto& joystick_guid_list = joystick_map[guid];
+ const auto joystick_it =
+ std::find_if(joystick_guid_list.begin(), joystick_guid_list.end(),
+ [&sdl_joystick](const std::shared_ptr<SDLJoystick>& joystick) {
+ return joystick->GetSDLJoystick() == sdl_joystick;
+ });
+ (*joystick_it)->SetSDLJoystick(nullptr, [](SDL_Joystick*) {});
+}
+
+void HandleGameControllerEvent(const SDL_Event& event) {
+ switch (event.type) {
+ case SDL_JOYBUTTONUP: {
+ auto joystick = GetSDLJoystickBySDLID(event.jbutton.which);
+ if (joystick) {
+ joystick->SetButton(event.jbutton.button, false);
+ }
+ break;
+ }
+ case SDL_JOYBUTTONDOWN: {
+ auto joystick = GetSDLJoystickBySDLID(event.jbutton.which);
+ if (joystick) {
+ joystick->SetButton(event.jbutton.button, true);
+ }
+ break;
+ }
+ case SDL_JOYHATMOTION: {
+ auto joystick = GetSDLJoystickBySDLID(event.jhat.which);
+ if (joystick) {
+ joystick->SetHat(event.jhat.hat, event.jhat.value);
+ }
+ break;
+ }
+ case SDL_JOYAXISMOTION: {
+ auto joystick = GetSDLJoystickBySDLID(event.jaxis.which);
+ if (joystick) {
+ joystick->SetAxis(event.jaxis.axis, event.jaxis.value);
+ }
+ break;
+ }
+ case SDL_JOYDEVICEREMOVED:
+ LOG_DEBUG(Input, "Controller removed with Instance_ID {}", event.jdevice.which);
+ CloseJoystick(SDL_JoystickFromInstanceID(event.jdevice.which));
+ break;
+ case SDL_JOYDEVICEADDED:
+ LOG_DEBUG(Input, "Controller connected with device index {}", event.jdevice.which);
+ InitJoystick(event.jdevice.which);
+ break;
+ }
+}
+
+void CloseSDLJoysticks() {
+ std::lock_guard<std::mutex> lock(joystick_map_mutex);
+ joystick_map.clear();
+}
+
+void PollLoop() {
+ if (SDL_Init(SDL_INIT_JOYSTICK) < 0) {
+ LOG_CRITICAL(Input, "SDL_Init(SDL_INIT_JOYSTICK) failed with: {}", SDL_GetError());
+ return;
+ }
+
+ SDL_Event event;
+ while (initialized) {
+ // Wait for 10 ms or until an event happens
+ if (SDL_WaitEventTimeout(&event, 10)) {
+ // Don't handle the event if we are configuring
+ if (polling) {
+ event_queue.Push(event);
+ } else {
+ HandleGameControllerEvent(event);
+ }
+ }
+ }
+ CloseSDLJoysticks();
+ SDL_QuitSubSystem(SDL_INIT_JOYSTICK);
+}
+
+class SDLButton final : public Input::ButtonDevice {
+public:
+ explicit SDLButton(std::shared_ptr<SDLJoystick> joystick_, int button_)
+ : joystick(std::move(joystick_)), button(button_) {}
+
+ bool GetStatus() const override {
+ return joystick->GetButton(button);
+ }
+
+private:
+ std::shared_ptr<SDLJoystick> joystick;
+ int button;
+};
+
+class SDLDirectionButton final : public Input::ButtonDevice {
+public:
+ explicit SDLDirectionButton(std::shared_ptr<SDLJoystick> joystick_, int hat_, Uint8 direction_)
+ : joystick(std::move(joystick_)), hat(hat_), direction(direction_) {}
+
+ bool GetStatus() const override {
+ return joystick->GetHatDirection(hat, direction);
+ }
+
+private:
+ std::shared_ptr<SDLJoystick> joystick;
+ int hat;
+ Uint8 direction;
+};
+
+class SDLAxisButton final : public Input::ButtonDevice {
+public:
+ explicit SDLAxisButton(std::shared_ptr<SDLJoystick> joystick_, int axis_, float threshold_,
+ bool trigger_if_greater_)
+ : joystick(std::move(joystick_)), axis(axis_), threshold(threshold_),
+ trigger_if_greater(trigger_if_greater_) {}
+
+ bool GetStatus() const override {
+ float axis_value = joystick->GetAxis(axis);
+ if (trigger_if_greater)
+ return axis_value > threshold;
+ return axis_value < threshold;
+ }
+
+private:
+ std::shared_ptr<SDLJoystick> joystick;
+ int axis;
+ float threshold;
+ bool trigger_if_greater;
+};
+
+class SDLAnalog final : public Input::AnalogDevice {
+public:
+ SDLAnalog(std::shared_ptr<SDLJoystick> joystick_, int axis_x_, int axis_y_)
+ : joystick(std::move(joystick_)), axis_x(axis_x_), axis_y(axis_y_) {}
+
+ std::tuple<float, float> GetStatus() const override {
+ return joystick->GetAnalog(axis_x, axis_y);
+ }
+
+private:
+ std::shared_ptr<SDLJoystick> joystick;
+ int axis_x;
+ int axis_y;
+};
+
+/// A button device factory that creates button devices from SDL joystick
+class SDLButtonFactory final : public Input::Factory<Input::ButtonDevice> {
+public:
+ /**
+ * Creates a button device from a joystick button
+ * @param params contains parameters for creating the device:
+ * - "guid": the guid of the joystick to bind
+ * - "port": the nth joystick of the same type to bind
+ * - "button"(optional): the index of the button to bind
+ * - "hat"(optional): the index of the hat to bind as direction buttons
+ * - "axis"(optional): the index of the axis to bind
+ * - "direction"(only used for hat): the direction name of the hat to bind. Can be "up",
+ * "down", "left" or "right"
+ * - "threshold"(only used for axis): a float value in (-1.0, 1.0) which the button is
+ * triggered if the axis value crosses
+ * - "direction"(only used for axis): "+" means the button is triggered when the axis
+ * value is greater than the threshold; "-" means the button is triggered when the axis
+ * value is smaller than the threshold
+ */
+ std::unique_ptr<Input::ButtonDevice> Create(const Common::ParamPackage& params) override {
+ const std::string guid = params.Get("guid", "0");
+ const int port = params.Get("port", 0);
+
+ auto joystick = GetSDLJoystickByGUID(guid, port);
+
+ if (params.Has("hat")) {
+ const int hat = params.Get("hat", 0);
+ const std::string direction_name = params.Get("direction", "");
+ Uint8 direction;
+ if (direction_name == "up") {
+ direction = SDL_HAT_UP;
+ } else if (direction_name == "down") {
+ direction = SDL_HAT_DOWN;
+ } else if (direction_name == "left") {
+ direction = SDL_HAT_LEFT;
+ } else if (direction_name == "right") {
+ direction = SDL_HAT_RIGHT;
+ } else {
+ direction = 0;
+ }
+ // This is necessary so accessing GetHat with hat won't crash
+ joystick->SetHat(hat, SDL_HAT_CENTERED);
+ return std::make_unique<SDLDirectionButton>(joystick, hat, direction);
+ }
+
+ if (params.Has("axis")) {
+ const int axis = params.Get("axis", 0);
+ const float threshold = params.Get("threshold", 0.5f);
+ const std::string direction_name = params.Get("direction", "");
+ bool trigger_if_greater;
+ if (direction_name == "+") {
+ trigger_if_greater = true;
+ } else if (direction_name == "-") {
+ trigger_if_greater = false;
+ } else {
+ trigger_if_greater = true;
+ LOG_ERROR(Input, "Unknown direction {}", direction_name);
+ }
+ // This is necessary so accessing GetAxis with axis won't crash
+ joystick->SetAxis(axis, 0);
+ return std::make_unique<SDLAxisButton>(joystick, axis, threshold, trigger_if_greater);
+ }
+
+ const int button = params.Get("button", 0);
+ // This is necessary so accessing GetButton with button won't crash
+ joystick->SetButton(button, false);
+ return std::make_unique<SDLButton>(joystick, button);
+ }
+};
+
+/// An analog device factory that creates analog devices from SDL joystick
+class SDLAnalogFactory final : public Input::Factory<Input::AnalogDevice> {
+public:
+ /**
+ * Creates analog device from joystick axes
+ * @param params contains parameters for creating the device:
+ * - "guid": the guid of the joystick to bind
+ * - "port": the nth joystick of the same type
+ * - "axis_x": the index of the axis to be bind as x-axis
+ * - "axis_y": the index of the axis to be bind as y-axis
+ */
+ std::unique_ptr<Input::AnalogDevice> Create(const Common::ParamPackage& params) override {
+ const std::string guid = params.Get("guid", "0");
+ const int port = params.Get("port", 0);
+ const int axis_x = params.Get("axis_x", 0);
+ const int axis_y = params.Get("axis_y", 1);
+
+ auto joystick = GetSDLJoystickByGUID(guid, port);
+
+ // This is necessary so accessing GetAxis with axis_x and axis_y won't crash
+ joystick->SetAxis(axis_x, 0);
+ joystick->SetAxis(axis_y, 0);
+ return std::make_unique<SDLAnalog>(joystick, axis_x, axis_y);
+ }
+};
+
+void Init() {
+ using namespace Input;
+ RegisterFactory<ButtonDevice>("sdl", std::make_shared<SDLButtonFactory>());
+ RegisterFactory<AnalogDevice>("sdl", std::make_shared<SDLAnalogFactory>());
+ polling = false;
+ initialized = true;
+}
+
+void Shutdown() {
+ if (initialized) {
+ using namespace Input;
+ UnregisterFactory<ButtonDevice>("sdl");
+ UnregisterFactory<AnalogDevice>("sdl");
+ initialized = false;
+ }
+}
+
+Common::ParamPackage SDLEventToButtonParamPackage(const SDL_Event& event) {
+ Common::ParamPackage params({{"engine", "sdl"}});
+ switch (event.type) {
+ case SDL_JOYAXISMOTION: {
+ auto joystick = GetSDLJoystickBySDLID(event.jaxis.which);
+ params.Set("port", joystick->GetPort());
+ params.Set("guid", joystick->GetGUID());
+ params.Set("axis", event.jaxis.axis);
+ if (event.jaxis.value > 0) {
+ params.Set("direction", "+");
+ params.Set("threshold", "0.5");
+ } else {
+ params.Set("direction", "-");
+ params.Set("threshold", "-0.5");
+ }
+ break;
+ }
+ case SDL_JOYBUTTONUP: {
+ auto joystick = GetSDLJoystickBySDLID(event.jbutton.which);
+ params.Set("port", joystick->GetPort());
+ params.Set("guid", joystick->GetGUID());
+ params.Set("button", event.jbutton.button);
+ break;
+ }
+ case SDL_JOYHATMOTION: {
+ auto joystick = GetSDLJoystickBySDLID(event.jhat.which);
+ params.Set("port", joystick->GetPort());
+ params.Set("guid", joystick->GetGUID());
+ params.Set("hat", event.jhat.hat);
+ switch (event.jhat.value) {
+ case SDL_HAT_UP:
+ params.Set("direction", "up");
+ break;
+ case SDL_HAT_DOWN:
+ params.Set("direction", "down");
+ break;
+ case SDL_HAT_LEFT:
+ params.Set("direction", "left");
+ break;
+ case SDL_HAT_RIGHT:
+ params.Set("direction", "right");
+ break;
+ default:
+ return {};
+ }
+ break;
+ }
+ }
+ return params;
+}
+
+namespace Polling {
+
+class SDLPoller : public InputCommon::Polling::DevicePoller {
+public:
+ void Start() override {
+ event_queue.Clear();
+ polling = true;
+ }
+
+ void Stop() override {
+ polling = false;
+ }
+};
+
+class SDLButtonPoller final : public SDLPoller {
+public:
+ Common::ParamPackage GetNextInput() override {
+ SDL_Event event;
+ while (event_queue.Pop(event)) {
+ switch (event.type) {
+ case SDL_JOYAXISMOTION:
+ if (std::abs(event.jaxis.value / 32767.0) < 0.5) {
+ break;
+ }
+ case SDL_JOYBUTTONUP:
+ case SDL_JOYHATMOTION:
+ return SDLEventToButtonParamPackage(event);
+ }
+ }
+ return {};
+ }
+};
+
+class SDLAnalogPoller final : public SDLPoller {
+public:
+ void Start() override {
+ SDLPoller::Start();
+
+ // Reset stored axes
+ analog_xaxis = -1;
+ analog_yaxis = -1;
+ analog_axes_joystick = -1;
+ }
+
+ Common::ParamPackage GetNextInput() override {
+ SDL_Event event;
+ while (event_queue.Pop(event)) {
+ if (event.type != SDL_JOYAXISMOTION || std::abs(event.jaxis.value / 32767.0) < 0.5) {
+ continue;
+ }
+ // An analog device needs two axes, so we need to store the axis for later and wait for
+ // a second SDL event. The axes also must be from the same joystick.
+ int axis = event.jaxis.axis;
+ if (analog_xaxis == -1) {
+ analog_xaxis = axis;
+ analog_axes_joystick = event.jaxis.which;
+ } else if (analog_yaxis == -1 && analog_xaxis != axis &&
+ analog_axes_joystick == event.jaxis.which) {
+ analog_yaxis = axis;
+ }
+ }
+ Common::ParamPackage params;
+ if (analog_xaxis != -1 && analog_yaxis != -1) {
+ auto joystick = GetSDLJoystickBySDLID(event.jaxis.which);
+ params.Set("engine", "sdl");
+ params.Set("port", joystick->GetPort());
+ params.Set("guid", joystick->GetGUID());
+ params.Set("axis_x", analog_xaxis);
+ params.Set("axis_y", analog_yaxis);
+ analog_xaxis = -1;
+ analog_yaxis = -1;
+ analog_axes_joystick = -1;
+ return params;
+ }
+ return params;
+ }
+
+private:
+ int analog_xaxis = -1;
+ int analog_yaxis = -1;
+ SDL_JoystickID analog_axes_joystick = -1;
+};
+
+void GetPollers(InputCommon::Polling::DeviceType type,
+ std::vector<std::unique_ptr<InputCommon::Polling::DevicePoller>>& pollers) {
+ switch (type) {
+ case InputCommon::Polling::DeviceType::Analog:
+ pollers.emplace_back(std::make_unique<SDLAnalogPoller>());
+ break;
+ case InputCommon::Polling::DeviceType::Button:
+ pollers.emplace_back(std::make_unique<SDLButtonPoller>());
+ break;
+ }
+}
+} // namespace Polling
+} // namespace SDL
+} // namespace InputCommon
diff --git a/src/input_common/sdl/sdl_impl.h b/src/input_common/sdl/sdl_impl.h
new file mode 100644
index 000000000..c152fa747
--- /dev/null
+++ b/src/input_common/sdl/sdl_impl.h
@@ -0,0 +1,51 @@
+// Copyright 2017 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <memory>
+#include <vector>
+#include "core/frontend/input.h"
+
+union SDL_Event;
+namespace Common {
+class ParamPackage;
+}
+namespace InputCommon {
+namespace Polling {
+class DevicePoller;
+enum class DeviceType;
+} // namespace Polling
+} // namespace InputCommon
+
+namespace InputCommon {
+namespace SDL {
+
+/// Initializes and registers SDL device factories
+void Init();
+
+/// Unresisters SDL device factories and shut them down.
+void Shutdown();
+
+/// Needs to be called before SDL_QuitSubSystem.
+void CloseSDLJoysticks();
+
+/// Handle SDL_Events for joysticks from SDL_PollEvent
+void HandleGameControllerEvent(const SDL_Event& event);
+
+/// A Loop that calls HandleGameControllerEvent until Shutdown is called
+void PollLoop();
+
+/// Creates a ParamPackage from an SDL_Event that can directly be used to create a ButtonDevice
+Common::ParamPackage SDLEventToButtonParamPackage(const SDL_Event& event);
+
+namespace Polling {
+
+/// Get all DevicePoller that use the SDL backend for a specific device type
+void GetPollers(InputCommon::Polling::DeviceType type,
+ std::vector<std::unique_ptr<InputCommon::Polling::DevicePoller>>& pollers);
+
+} // namespace Polling
+} // namespace SDL
+} // namespace InputCommon