This is an attempt to fix mission upload and download with QGC on a
lossy link. The way it should work according to the protocol on
https://mavlink.io/en/protocol/mission.html is that in general
the ground station should be concerned about timeouts and
retransmission. This means the autopilot does not need to retransmit by
itself but just answer requests.
This seems like it would make the transfer less robust, however, it
actually resolves an edge case where QGC fails to make requests because
it gets spammed by the autopilot and keeps resetting the timeout.
ROI yaw control: configure yawing capability of mount in vmount parameters.
If configured that mount has no yaw control, vehicle will yaw towards ROI, irrespective of MIS_YAWMODE.
Vehicle will behave according to MIS_YAWMODE when there is no ROI.
The way the broadcast IP is currently fetched is by sending an ioctl()
request. The limitation of this is that the broadcast address may not
be set on the network interface (more specifically, it is usually not
set in docker containers). In those cases, it results in the broadcast
address becoming 0.0.0.0, which is not valid [1].
This fix uses the network IP and the netmask to compute the directed
broadcast address. This should be more reliable, as both of those are
always set on the network interface.
[1]: https://tools.ietf.org/html/rfc1122, section 3.2.1.3 (a)
This fixes the case where a topic instance is already subscribed, and
advertised later. The subscriber will create the DeviceNode with default
priority, and the advertiser will just use the existing DeviceNode,
without updating to the requested priority.
The debug messages are too verbose to be run in a production vehicle and inherently were something that should only be run in SITL / debug sessions on hardware. Switching the flag to the PX4_DEBUG() macro does not only make this more explicit, but also saves a lot of flash space that otherwise was consumed by the strings.