AP_Camera: consuming component id = 100?

[rmackay9]

Bug Report

We have had at least one report that indicates that AP's camera library may be consuming mavlink zoom commands with component id 100 (meant for a mavlink enabled camera) when it should only be consuming commands with the autopilot's component id (e.g. 1)

Version
What version was the issue encountered with

Platform
[x] All
[ ] AntennaTracker
[ ] Copter
[ ] Plane
[ ] Rover
[ ] Submarine

This was reported by @CraigElder

[rubikscube05]

Hi @rmackay9, I would like to work on this issue. Could you please assign it to me?

[afzalansari12]

@rubikscube05 Thanks for working on this. A few suggestions:

1. This only guards MAV_CMD_SET_CAMERA_ZOOM, but the same issue applies to MAV_CMD_SET_CAMERA_FOCUS and all other camera commands routed through handle_command_camera (capture, tracking, video, etc.).

2. Only checking MAV_COMP_ID_CAMERA (100) misses cameras at compids 101–105 (MAV_COMP_ID_CAMERA2 through MAV_COMP_ID_CAMERA6).

3. A cleaner fix would be to add the check in GCS_MAVLINK::handle_command_camera() in GCS_Common.cpp instead — that's the single gateway for all camera commands. This follows the existing pattern from handle_preflight_reboot:

MAV_RESULT GCS_MAVLINK::handle_command_camera(const mavlink_command_int_t &packet)
{
    // don't process camera commands not targeted at the autopilot
    if ((packet.target_component != MAV_COMP_ID_ALL) && (packet.target_component != mavlink_system.compid)) {
        return MAV_RESULT_UNSUPPORTED;
    }

    AP_Camera *camera = AP::camera();
    if (camera == nullptr) {
        return MAV_RESULT_UNSUPPORTED;
    }

    return camera->handle_command(packet);
}

[rmackay9]

Hi agree that @afzalansari12's fix look correct, txs!

[peterbarker]

So @afzalansari12 is a subset of the functionality in #33493

If ArduPilot ever sees a camera with compid=100 then we will not process the messages for that camera locally (or we have a different bug!).

[rmackay9]

I think we should go with @peterbarker's PR actually because it's more complete so I have added it for review at the next dev call, txs!

[afzalansari12]

Sounds good, makes sense to go with #33493 since it's more complete. Thanks for the feedback!