Error Active

[Steffen Rose <ro@emtas.de>]

Hello,

I write a generic application, that should work with different socketcan driver implementations. 
I know, there are different possibilities to get the CAN controller state. And I see, that different 
implementation do not implement all of them.

What is the standard way to get the state change from Error Passive to Error Active?

My current way (in short incomplete form):

can_err_mask_t err_mask = CAN_ERR_FLAG | CAN_ERR_CRTL | CAN_ERR_PROT | CAN_ERR_BUSOFF;
setsockopt(mBSDSocket, SOL_CAN_RAW, CAN_RAW_ERR_FILTER, &err_mask, sizeof(err_mask));

got = read(mBSDSocket, &frame, sizeof(struct can_frame));
if (frame.can_id & CAN_ERR_FLAG) {
  if (frame.can_id & CAN_ERR_PROT) {
    if (frame.data[2] & CAN_ERR_PROT_ACTIVE) {

=> change to Error active

    }
  }
}

This will work with the Systec USB interface, but do not work with Peak, Beagle bone, EMS CPC.
I have seen the implementation in the can utils.

I know, the libsocketcan implements a different way. But I cannot extract the relevant parts. 
And I think a have to poll the current state with it and I search an event based mechanism.

-- 
Mit freundlichen Grüßen / Regards
Steffen Rose
www.emtas.de