# need to wait for a heartbeat to arrive as then mavutil will
# select the correct set of messages for us to receive in
# self.mav.messages. You can actually recieve messages with
# recv_match and those will not be in self.mav.messages until
# you do this!
Also, wait_heartbeat ignores heartbeats from e.g. MAVProxy
It was observed from a log of a failed CI test that the ACK from
clearing the rally items took 6 wallclock seconds to arrive.
We were not waiting for that ACK to arrive before sending the request
for the mission item count, but if it has taken more than six seconds
for the ACK to arrive it is reasonable to assume that MISSION_COUNT
could very well take more than the 10 seconds we allow for it.
If we drain the mav before sending the request for the mission count we
should remove any signficiant timing problem due to a backlog of mavlnk
messages, but the amount of traffic here is problematic.
Also drain in lots of other places where we might be spending way too
long parsing messages.
MAVProxy's output is read by autotest via pexpect.
SITL's output is read by MAVProxy.
If we don't read MAVProxy's stdout then it doesn't read SITL and
everything stops.
Also, since we need to drain pexpects as part of reboot, and applying
parameter files requires rebooting... we need to append the expect
objects to the global list before we apply parameter files. So move
that call.
This makes the AutoTest instance cognizant of the binary log files it is creating. This will be useful for checking the contents of the log files created.
If a long-running process drains the mavlink stream rather than parsing
it then the cached timestamp can be very, very out-of-date. When we
next receieve a timestamp, then, there can be a signficant change in
time when we weren't expecting it.
run_cmd_get_ack can't use get_sim_time() as it might swallow the ack it
is looking for.
This is important when rebooting as the ArduPilot process can block on
sending to stdout, which pexpect is reading from. While rebooting we're
waiting for a parameter to be reset to a different value in this loop,
which could take quite some time.
MAVProxy can fetch parameters using FTP rather than normal param
mechanism. Currently this does not emit any of our statustext
information - like the text we're looking for in this test
