Exclusive open is not required, but we now need to ensure the queue size
is set atomically.
It avoids a race condition between 2 single-instance advertisers,
where one of them would fail to open the node with -EBUSY.
Possible race conditions (they all happen between the check of existence
of a topic and trying to create the node):
- single instance, with multiple advertisers during the first advertise:
both advertisers see the topic as non-existent and try to advertise it.
One of them will fail, leading to an error message.
This is the cause for telemetry_status advert failure seen in SITL in
rare cases.
- multi-instance: subscription to non-existing instance -> px4_open fails,
and the subscriber tries to create the node. If during that time a
publisher publishes that instance, the subscriber will get (instance+1)
(or fails if the max number of instances is exceeded).
This is a race that goes pretty much unnoticed.
- multi-instance: 2 publishers can get the same instance (if is_published()
is false in case both have not published data yet).
This can also go unnoticed.
Therefore the patch changes where _advertised is set: it is now set
directly during the advertisement instead of during publication.
* Add kdevelop to gitignore
* Add test stubs
* Rename px4_add_gtest to px4_add_unit_gtest
* Add infrastructure to run functional tests
* Add example tests with parameters and uorb messages
* Fix memory issues in destructors in uORB manager and CDev
* Add a more real-world test of the collision prevention
Fixes these invalid format strings:
- A `%d` for a pointer (replaced it by `%p`)
- A 0x%08x (and a 0x%0x8!) for a pointer (replaced by %p)
- 2 cases of `%d` for a `ssize_t` (replaced it by `%zi`)
- 1 case of a %u for an `int` (replaced by %i)
- 3 cases of %d for a `long` (replaced by %ld)
- 19 cases of `%d`, `%i`, `%u` or `%lu` for a `size_t` (replaced it by `%zu`)
- An unused formatting argument (removed it)
- A missing `%d` (added it)
- A missing `%s` (added it)
- 2 cases of `%llu` for a `uint64_t` (replaced it by `"%" PRIu64`)
- 6 cases of giving a string directly as format string (replaced it by `("%s", string)`)
- 2 cases of %*-s, which should probably have been %-*s.
(Looks like NuttX accepts (the invalid) %*-s, but other platforms don't.)
- A %04x for a `uint32_t` (replaced by "%04" PRIx32)
Beat Küng