door_status not coming through

[zacnelson]

Looks like shared_handlers has changed with v6.X of vi-firmware and our previous implementation of door_status signals is no longer working.

I've modified the doorStatusDecoder(...) such that it is now returns an openxc_DynamicField. I will create an issue branch from next and get this working. Below are the changes I made to shared_handlers.

Right now, I'm getting an issue where the call to publishVehicleMessage(...) is causing the VI to hang and stall.

openxc_DynamicField openxc::signals::handlers::doorStatusDecoder(CanSignal* signal,
        CanSignal* signals, int signalCount,
        Pipeline* pipeline, float value, bool* send) {
    openxc_DynamicField ajarStatus = booleanDecoder(signal, signals, signalCount, 
            pipeline, value, send);
    *send = openxc::can::read::shouldSend(signal, value);
    if(send) {
        openxc_DynamicField doorIdValue = {0};
        doorIdValue.has_type = true;
        doorIdValue.type = openxc_DynamicField_Type_STRING;
        doorIdValue.has_string_value = true;
        if(!strcmp(signal->genericName, "driver_door")) {
            strcpy(doorIdValue.string_value, "driver");
        } else if(!strcmp(signal->genericName, "passenger_door")) {
            strcpy(doorIdValue.string_value, "passenger");
        } else if(!strcmp(signal->genericName, "rear_right_door")) {
            strcpy(doorIdValue.string_value, "rear_right");
        } else if(!strcmp(signal->genericName, "rear_left_door")) {
            strcpy(doorIdValue.string_value, "rear_left");
        } else {
            strcpy(doorIdValue.string_value, signal->genericName);
        }
        publishVehicleMessage(
                openxc::signals::handlers::DOOR_STATUS_GENERIC_NAME,
                &doorIdValue, &ajarStatus, pipeline);
    }

    // Block the normal sending, we overrode it
    *send = false;
    return openxc::payload::wrapNumber(0);
}

The door_status signals are mapped in the following format:

"Driver_door_status_signal": {
    "generic_name": "driver_door",
    "decoder": "doorStatusDecoder",
    "send_same": false
},

The idea is that the door_status event-based signals are only sent when something changes (i.e. when a door opens or closes.)

Any thoughts why publishVehicleMessage crashes? Commenting out that line fixes the crash, but then I don't get any JSON output, of course.

[peplin]

Thanks for the help finding this bug, Zac. I think it's fixed now. There were two problems:

• The doorStatusDecoder and tirePressureDecoder had a call to decodeSignal, which would end up being a recursive call when running the full VI stack. It needed to be a more specific decoder, i.e. booleanDecoder as you have it.
• Signal decoders were being passed NULL as the pipeline argument (https://github.com/openxc/vi-firmware/blob/master/src/can/canread.cpp#L236). I've added a unit tests for this and fixed it so it passes in the proper, global output pipeline object. I think this was the root cause of your crash - inside publishVehicleMessage it would try to use the pipeline, but it was NULL.

[peplin]

I'll close this bug for now, but let me know when you have time to give it a test (in next as of f0577cd) and if it's still a problem.

[zacnelson]

Cool, thanks for catching the pipeline issue! In the updated door examples, it looks like the values would be sent every time there's a CAN message. Here's my suggestion:

• Because we're using a specific decoder, booleanDecoder, we need to call shouldSend(...) in order to determine if/when to send the value. I suggest we add a send_same=false flag to each signal as in my comment above. That way you only get door signal event messages when a door opens or closes.

[peplin]

Thanks, just added that too.