Fallback if mouse or keyboard interface is not working.

Problems with tablets on Windows.

input/dinput.c

@@ -102,7 +102,10 @@ static bool dinput_init_context(void)
 static void *dinput_init(void)
 {
    if (!dinput_init_context())
+   {
+      RARCH_ERR("Failed to start DirectInput driver.\n");
       return NULL;
+   }
 
    struct dinput_input *di = (struct dinput_input*)calloc(1, sizeof(*di));
    if (!di)
@@ -112,47 +115,47 @@ static void *dinput_init(void)
    if (FAILED(IDirectInput8_CreateDevice(g_ctx, GUID_SysKeyboard, &di->keyboard, NULL)))
    {
       RARCH_ERR("Failed to create keyboard device.\n");
-      goto error;
+      di->keyboard = NULL;
    }
 
    if (FAILED(IDirectInput8_CreateDevice(g_ctx, GUID_SysMouse, &di->mouse, NULL)))
    {
       RARCH_ERR("Failed to create mouse device.\n");
-      goto error;
+      di->mouse = NULL;
    }
 #else
    if (FAILED(IDirectInput8_CreateDevice(g_ctx, &GUID_SysKeyboard, &di->keyboard, NULL)))
    {
       RARCH_ERR("Failed to create keyboard device.\n");
-      goto error;
+      di->keyboard = NULL;
    }
    if (FAILED(IDirectInput8_CreateDevice(g_ctx, &GUID_SysMouse, &di->mouse, NULL)))
    {
       RARCH_ERR("Failed to create mouse device.\n");
-      goto error;
+      di->mouse = NULL;
    }
 #endif
 
+   if (di->keyboard)
+   {
       IDirectInputDevice8_SetDataFormat(di->keyboard, &c_dfDIKeyboard);
       IDirectInputDevice8_SetCooperativeLevel(di->keyboard,
             (HWND)driver.video_window, DISCL_NONEXCLUSIVE | DISCL_FOREGROUND);
       IDirectInputDevice8_Acquire(di->keyboard);
+   }
 
+   if (di->mouse)
+   {
       IDirectInputDevice8_SetDataFormat(di->mouse, &c_dfDIMouse2);
       IDirectInputDevice8_SetCooperativeLevel(di->mouse, (HWND)driver.video_window,
             DISCL_NONEXCLUSIVE | DISCL_FOREGROUND);
       IDirectInputDevice8_Acquire(di->mouse);
+   }
 
    input_init_keyboard_lut(rarch_key_map_dinput);
    di->joypad = input_joypad_init_driver(g_settings.input.joypad_driver);
 
    return di;
-
-error:
-   RARCH_ERR("Failed to start DirectInput driver.\n");
-   dinput_destroy_context();
-   free(di);
-   return NULL;
 }
 
 static void dinput_poll(void *data)
@@ -160,15 +163,21 @@ static void dinput_poll(void *data)
    struct dinput_input *di = (struct dinput_input*)data;
 
    memset(di->state, 0, sizeof(di->state));
+   if (di->keyboard)
+   {
       if (FAILED(IDirectInputDevice8_GetDeviceState(di->keyboard, sizeof(di->state), di->state)))
       {
          IDirectInputDevice8_Acquire(di->keyboard);
          if (FAILED(IDirectInputDevice8_GetDeviceState(di->keyboard, sizeof(di->state), di->state)))
             memset(di->state, 0, sizeof(di->state));
       }
+   }
 
+   if (di->mouse)
+   {
       DIMOUSESTATE2 mouse_state;
       memset(&mouse_state, 0, sizeof(mouse_state));
+
       if (FAILED(IDirectInputDevice8_GetDeviceState(di->mouse, sizeof(mouse_state), &mouse_state)))
       {
          IDirectInputDevice8_Acquire(di->mouse);
@@ -188,6 +197,7 @@ static void dinput_poll(void *data)
       ScreenToClient((HWND)driver.video_window, &point);
       di->mouse_x = point.x;
       di->mouse_y = point.y;
+   }
 
    input_joypad_poll(di->joypad);
 }