The RTT callback for a super-frame cycle uses the `arg` pointer to set
the message value that then is handed to the GoMacH thread. However,
in both instances the timer is scheduled the constant
`GNRC_GOMACH_EVENT_RTT_NEW_CYCLE` is provided. This means the argument
is not really necessary.
The ubjson module has a number of quality defects and is unsafe.
Considering CBOR is popular, standarized and supported in RIOT and that
the ubjson implementation is a home-grown one whose API will likely be
unfamiliar to new users, I propose to delete it.
This removal, of course, dows not have to be NOW. We can deprecate it for
one or two releases before.
What's wrong with this module?
- Unsafe: the parsing is done recursively. This is embedded in the API, so it
is not possible to fix it without changing the API. A document with too much
nesting can cause a stack overflow.
- Does not validate writing: it is possible to produce invalid output. From
the docs:
> The library won't complain if you write multiple values that are not
> inside an array or object. The result will just not be properly serialized.
- Poorly tested. As shown by #11702, #11703 the tests were not even detecting
that a False was stored as True.
- In line with the previous remark, see
68dc5b0d6e/tests/unittests/tests-ubjson/tests-ubjson.c (L66-L77)
Why is the following code in the unit tests??
```c
irq_disable();
sched_set_status(data->main_thread, STATUS_PENDING);
```
- #2175 is still unfixed after 3.5 years.
- Code quality. The code has multiline macros that assign variables and
return. See c332514875/sys/ubjson/ubjson-write.c (L34-L41)
Can we mark it as deprecated this release and sweep it in the following one?
This fits with the semantics of this function which doesn't provide or
uses any state of the reassembly buffer provided by the user, but finds
the entry itself and then removes it. This gives the user no chance to
remove the packet in the reassembly buffer entry, so
`gnrc_sixlowpan_frag_rb_rm_by_datagram()` has to release the packet
(other than `gnrc_sixlowpan_frag_rb_remove()` where not releasing the
packet is desired as it might be handed up to an upper layer).
