Poll SDL device list to recover missing hotplug events

app/streaming/input/gamepad.cpp

@@ -97,6 +97,33 @@ SdlInputHandler::ensureStateForGamepad(SDL_JoystickID id)
     return findStateForGamepad(id);
 }
 
+void SdlInputHandler::pollForMissingGamepads()
+{
+    cleanupDetachedGamepads();
+
+    const int joystickCount = SDL_NumJoysticks();
+    for (int deviceIndex = 0; deviceIndex < joystickCount; deviceIndex++) {
+        if (!SDL_IsGameController(deviceIndex)) {
+            continue;
+        }
+
+        SDL_JoystickID jsId = SDL_JoystickGetDeviceInstanceID(deviceIndex);
+        if (jsId < 0 || findStateForGamepad(jsId) != nullptr) {
+            continue;
+        }
+
+        SDL_LogWarn(SDL_LOG_CATEGORY_APPLICATION,
+                    "Polling recovered missing gamepad add event (device index: %d, instance ID: %d)",
+                    deviceIndex,
+                    jsId);
+
+        SDL_ControllerDeviceEvent controllerEvent = {};
+        controllerEvent.type = SDL_CONTROLLERDEVICEADDED;
+        controllerEvent.which = deviceIndex;
+        handleControllerDeviceEvent(&controllerEvent);
+    }
+}
+
 void SdlInputHandler::cleanupDetachedGamepads()
 {
     for (int i = 0; i < MAX_GAMEPADS; i++) {

app/streaming/input/input.h

@@ -118,6 +118,8 @@ public:
 
     void handleJoystickRemovalEvent(SDL_JoyDeviceEvent* event);
 
+    void pollForMissingGamepads();
+
     void sendText(QString& string);
 
     void rumble(uint16_t controllerNumber, uint16_t lowFreqMotor, uint16_t highFreqMotor);

app/streaming/session.cpp

@@ -2206,6 +2206,7 @@ void Session::exec()
         // issues that could cause indefinite timeouts, delayed joystick detection,
         // and other problems.
         if (!SDL_WaitEventTimeout(&event, 1000)) {
+            m_InputHandler->pollForMissingGamepads();
             updateEffectiveAudioMuteState();
             presence.runCallbacks();
             continue;