general: Use deducation guides for std::lock_guard and std::unique_lock

Since C++17, the introduction of deduction guides for locking facilities
means that we no longer need to hardcode the mutex type into the locks
themselves, making it easier to switch mutex types, should it ever be
necessary in the future.

src/input_common/keyboard.cpp

@@ -36,18 +36,18 @@ struct KeyButtonPair {
 class KeyButtonList {
 public:
     void AddKeyButton(int key_code, KeyButton* key_button) {
-        std::lock_guard<std::mutex> guard(mutex);
+        std::lock_guard guard{mutex};
         list.push_back(KeyButtonPair{key_code, key_button});
     }
 
     void RemoveKeyButton(const KeyButton* key_button) {
-        std::lock_guard<std::mutex> guard(mutex);
+        std::lock_guard guard{mutex};
         list.remove_if(
             [key_button](const KeyButtonPair& pair) { return pair.key_button == key_button; });
     }
 
     void ChangeKeyStatus(int key_code, bool pressed) {
-        std::lock_guard<std::mutex> guard(mutex);
+        std::lock_guard guard{mutex};
         for (const KeyButtonPair& pair : list) {
             if (pair.key_code == key_code)
                 pair.key_button->status.store(pressed);
@@ -55,7 +55,7 @@ public:
     }
 
     void ChangeAllKeyStatus(bool pressed) {
-        std::lock_guard<std::mutex> guard(mutex);
+        std::lock_guard guard{mutex};
         for (const KeyButtonPair& pair : list) {
             pair.key_button->status.store(pressed);
         }

src/input_common/motion_emu.cpp

@@ -40,7 +40,7 @@ public:
     void Tilt(int x, int y) {
         auto mouse_move = Common::MakeVec(x, y) - mouse_origin;
         if (is_tilting) {
-            std::lock_guard<std::mutex> guard(tilt_mutex);
+            std::lock_guard guard{tilt_mutex};
             if (mouse_move.x == 0 && mouse_move.y == 0) {
                 tilt_angle = 0;
             } else {
@@ -52,13 +52,13 @@ public:
     }
 
     void EndTilt() {
-        std::lock_guard<std::mutex> guard(tilt_mutex);
+        std::lock_guard guard{tilt_mutex};
         tilt_angle = 0;
         is_tilting = false;
     }
 
     std::tuple<Common::Vec3<float>, Common::Vec3<float>> GetStatus() {
-        std::lock_guard<std::mutex> guard(status_mutex);
+        std::lock_guard guard{status_mutex};
         return status;
     }
 
@@ -95,7 +95,7 @@ private:
             old_q = q;
 
             {
-                std::lock_guard<std::mutex> guard(tilt_mutex);
+                std::lock_guard guard{tilt_mutex};
 
                 // Find the quaternion describing current 3DS tilting
                 q = Common::MakeQuaternion(
@@ -117,7 +117,7 @@ private:
 
             // Update the sensor state
             {
-                std::lock_guard<std::mutex> guard(status_mutex);
+                std::lock_guard guard{status_mutex};
                 status = std::make_tuple(gravity, angular_rate);
             }
         }

src/input_common/sdl/sdl_impl.cpp

@@ -55,22 +55,22 @@ public:
         : guid{std::move(guid_)}, port{port_}, sdl_joystick{joystick, deleter} {}
 
     void SetButton(int button, bool value) {
-        std::lock_guard<std::mutex> lock(mutex);
+        std::lock_guard lock{mutex};
         state.buttons[button] = value;
     }
 
     bool GetButton(int button) const {
-        std::lock_guard<std::mutex> lock(mutex);
+        std::lock_guard lock{mutex};
         return state.buttons.at(button);
     }
 
     void SetAxis(int axis, Sint16 value) {
-        std::lock_guard<std::mutex> lock(mutex);
+        std::lock_guard lock{mutex};
         state.axes[axis] = value;
     }
 
     float GetAxis(int axis) const {
-        std::lock_guard<std::mutex> lock(mutex);
+        std::lock_guard lock{mutex};
         return state.axes.at(axis) / 32767.0f;
     }
 
@@ -92,12 +92,12 @@ public:
     }
 
     void SetHat(int hat, Uint8 direction) {
-        std::lock_guard<std::mutex> lock(mutex);
+        std::lock_guard lock{mutex};
         state.hats[hat] = direction;
     }
 
     bool GetHatDirection(int hat, Uint8 direction) const {
-        std::lock_guard<std::mutex> lock(mutex);
+        std::lock_guard lock{mutex};
         return (state.hats.at(hat) & direction) != 0;
     }
     /**
@@ -140,7 +140,7 @@ private:
  * Get the nth joystick with the corresponding GUID
  */
 std::shared_ptr<SDLJoystick> SDLState::GetSDLJoystickByGUID(const std::string& guid, int port) {
-    std::lock_guard<std::mutex> lock(joystick_map_mutex);
+    std::lock_guard lock{joystick_map_mutex};
     const auto it = joystick_map.find(guid);
     if (it != joystick_map.end()) {
         while (it->second.size() <= port) {
@@ -161,7 +161,8 @@ std::shared_ptr<SDLJoystick> SDLState::GetSDLJoystickByGUID(const std::string& g
 std::shared_ptr<SDLJoystick> SDLState::GetSDLJoystickBySDLID(SDL_JoystickID sdl_id) {
     auto sdl_joystick = SDL_JoystickFromInstanceID(sdl_id);
     const std::string guid = GetGUID(sdl_joystick);
-    std::lock_guard<std::mutex> lock(joystick_map_mutex);
+
+    std::lock_guard lock{joystick_map_mutex};
     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(),
@@ -198,8 +199,9 @@ void SDLState::InitJoystick(int joystick_index) {
         LOG_ERROR(Input, "failed to open joystick {}", joystick_index);
         return;
     }
-    std::string guid = GetGUID(sdl_joystick);
-    std::lock_guard<std::mutex> lock(joystick_map_mutex);
+    const std::string guid = GetGUID(sdl_joystick);
+
+    std::lock_guard lock{joystick_map_mutex};
     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));
@@ -221,7 +223,7 @@ void SDLState::CloseJoystick(SDL_Joystick* sdl_joystick) {
     std::string guid = GetGUID(sdl_joystick);
     std::shared_ptr<SDLJoystick> joystick;
     {
-        std::lock_guard<std::mutex> lock(joystick_map_mutex);
+        std::lock_guard lock{joystick_map_mutex};
         // This call to guid is safe since the joystick is guaranteed to be in the map
         auto& joystick_guid_list = joystick_map[guid];
         const auto joystick_it =
@@ -274,7 +276,7 @@ void SDLState::HandleGameControllerEvent(const SDL_Event& event) {
 }
 
 void SDLState::CloseJoysticks() {
-    std::lock_guard<std::mutex> lock(joystick_map_mutex);
+    std::lock_guard lock{joystick_map_mutex};
     joystick_map.clear();
 }
 

src/input_common/udp/client.cpp

@@ -165,7 +165,7 @@ void Client::OnPadData(Response::PadData data) {
     Common::Vec3f accel = Common::MakeVec<float>(-data.accel.x, data.accel.y, -data.accel.z);
     Common::Vec3f gyro = Common::MakeVec<float>(-data.gyro.pitch, -data.gyro.yaw, data.gyro.roll);
     {
-        std::lock_guard<std::mutex> guard(status->update_mutex);
+        std::lock_guard guard(status->update_mutex);
 
         status->motion_status = {accel, gyro};
 

src/input_common/udp/udp.cpp

@@ -15,7 +15,7 @@ class UDPTouchDevice final : public Input::TouchDevice {
 public:
     explicit UDPTouchDevice(std::shared_ptr<DeviceStatus> status_) : status(std::move(status_)) {}
     std::tuple<float, float, bool> GetStatus() const {
-        std::lock_guard<std::mutex> guard(status->update_mutex);
+        std::lock_guard guard(status->update_mutex);
         return status->touch_status;
     }
 
@@ -27,7 +27,7 @@ class UDPMotionDevice final : public Input::MotionDevice {
 public:
     explicit UDPMotionDevice(std::shared_ptr<DeviceStatus> status_) : status(std::move(status_)) {}
     std::tuple<Common::Vec3<float>, Common::Vec3<float>> GetStatus() const {
-        std::lock_guard<std::mutex> guard(status->update_mutex);
+        std::lock_guard guard(status->update_mutex);
         return status->motion_status;
     }
 
@@ -41,7 +41,7 @@ public:
 
     std::unique_ptr<Input::TouchDevice> Create(const Common::ParamPackage& params) override {
         {
-            std::lock_guard<std::mutex> guard(status->update_mutex);
+            std::lock_guard guard(status->update_mutex);
             status->touch_calibration.emplace();
             // These default values work well for DS4 but probably not other touch inputs
             status->touch_calibration->min_x = params.Get("min_x", 100);