Hardfault ble_nus_send_data - SDK 17

[Roei]

Hi,

I've noticed that there was an issue with ble_nus in SDK 15.3 - detailed in this post.

I'm using SDK 17, and in my application, I don't check data_handler != NULL. When BLE_GATTS_EVT_HVN_TX_COMPLETE occurs, I just define ble_nus_evt_t evt and calls p_nus->data_handler. Probably took it from an example, I can't remember.

Is it safe? Should I use something else?

Thanks!

[Einar Thorsrud]

Hi,

This issue is fixed in SDK 17.0.2.

[Roei]

Hi,

Thanks for your response!

Does it fixed event when I don't use on_hvx_tx_complete() function? Also when I just call p_nus->data_handler() without any NULL validation?

Thanks!

[Einar Thorsrud]

Hi,

Perhaps I was a bit too quick My answer was related to the first part of your question, where the issue discussed in this thread is fixed.

Regarding the second question I do not fully understand it, as this is handled by the NUS service implementation (components\ble\ble_services\ble_nus\ble_nus.c) without you having to think about it. Perhaps you can share your code to provide context, and explain in more detail what you are asking about?

[Roei]

Hi,

This is the implementation in my application, under ble_nus.c:

case BLE_GATTS_EVT_HVN_TX_COMPLETE:
{
    //notify with empty data that some tx was completed.
    ble_nus_evt_t evt = {
                 .type = BLE_NUS_EVT_TX_RDY,
                 .p_nus = p_nus
                                     };
p_nus->data_handler(&evt);
}
break;

As it's not exactly as the SDK code, probably because it's from another example, I'm not sure if it's safe enough, because I don't have any validation if p_nus->data_handler != NULL.

In other cases of this switch, I can see other uses of p_nus->data_handler without validation.

What is your opinion?

Thanks!

[Einar Thorsrud]

Hi,

As long as you provided a data handler when you initialized the NSU Service, then this is no issue. (I cannot say more specific then that as I have not seen enough of your code)

[Roei]

Hi,

I've provided an handler during initialization, but events handler takes ble_nut_t pointer from an argument to the function, as following:

void OnBleNusEvent(ble_evt_t const * p_ble_evt, void * p_context)

if ((p_context == NULL) || (p_ble_evt == NULL))
{
   return;
}

ble_nus_t * p_nus = (ble_nus_t *)p_context;

After that, I'm using p_nus->data_handler.

Is it safe to use p_context?

Thanks!