Added SDL_JoystickGetXInputUserIndex()

include/SDL_joystick.h

@@ -384,6 +384,11 @@ extern DECLSPEC void SDLCALL SDL_JoystickClose(SDL_Joystick * joystick);
  */
 extern DECLSPEC SDL_JoystickPowerLevel SDLCALL SDL_JoystickCurrentPowerLevel(SDL_Joystick * joystick);
 
+/**
+ *  Return the XInput user index for this joystick, or -1 if it's not available
+ */
+extern DECLSPEC int SDLCALL SDL_JoystickGetXInputUserIndex(SDL_Joystick * joystick);
+
 /* Ends C function definitions when using C++ */
 #ifdef __cplusplus
 }

src/dynapi/SDL_dynapi_overrides.h

@@ -698,3 +698,4 @@
 #define SDL_GetDisplayOrientation SDL_GetDisplayOrientation_REAL
 #define SDL_HasColorKey SDL_HasColorKey_REAL
 #define SDL_CreateThreadWithStackSize SDL_CreateThreadWithStackSize_REAL
+#define SDL_JoystickGetXInputUserIndex SDL_JoystickGetXInputUserIndex_REAL

src/dynapi/SDL_dynapi_procs.h

@@ -752,3 +752,4 @@ SDL_DYNAPI_PROC(SDL_Thread*,SDL_CreateThreadWithStackSize,(SDL_ThreadFunction a,
 SDL_DYNAPI_PROC(SDL_Thread*,SDL_CreateThreadWithStackSize,(SDL_ThreadFunction a, const char *b, const size_t c, void *d),(a,b,c,d),return)
 #endif
 
+SDL_DYNAPI_PROC(int,SDL_JoystickGetXInputUserIndex,(SDL_Joystick *a),(a),return)

src/joystick/SDL_joystick.c

@@ -322,6 +322,7 @@ SDL_JoystickOpen(int device_index)
     }
 
     joystick->guid = driver->GetDeviceGUID(device_index);
+    joystick->userid = -1;
 
     if (joystick->naxes > 0) {
         joystick->axes = (SDL_JoystickAxisInfo *) SDL_calloc(joystick->naxes, sizeof(SDL_JoystickAxisInfo));
@@ -1556,4 +1557,12 @@ SDL_JoystickPowerLevel SDL_JoystickCurrentPowerLevel(SDL_Joystick * joystick)
     return joystick->epowerlevel;
 }
 
+int SDL_JoystickGetXInputUserIndex(SDL_Joystick * joystick)
+{
+    if (!SDL_PrivateJoystickValid(joystick)) {
+        return -1;
+    }
+    return joystick->userid;
+}
+
 /* vi: set ts=4 sw=4 expandtab: */

src/joystick/SDL_sysjoystick.h

@@ -43,6 +43,7 @@ struct _SDL_Joystick
     SDL_JoystickID instance_id; /* Device instance, monotonically increasing from 0 */
     char *name;                 /* Joystick name - system dependent */
     SDL_JoystickGUID guid;      /* Joystick guid */
+    int userid;                 /* XInput user index, if any */
 
     int naxes;                  /* Number of axis controls on the joystick */
     SDL_JoystickAxisInfo *axes;

src/joystick/windows/SDL_xinputjoystick.c

@@ -322,6 +322,7 @@ SDL_XINPUT_JoystickOpen(SDL_Joystick * joystick, JoyStick_DeviceData *joystickde
     SDL_zero(state);
     joystick->hwdata->bXInputHaptic = (XINPUTSETSTATE(userId, &state) == ERROR_SUCCESS);
     joystick->hwdata->userid = userId;
+    joystick->userid = userId;
 
     /* The XInput API has a hard coded button/axis mapping, so we just match it */
     if (SDL_XInputUseOldJoystickMapping()) {