This way we can unify handling of credentials that are attached to
messages, or can be queried for bus name owners or connection peers.
This also adds the ability to extend incomplete credential information
with data from /proc,
Also, provide a convenience call that will automatically determine the
most appropriate credential object for an incoming message, by using the
the attached information if possible, the sending name information if
available and otherwise the peer's credentials.
I know that this is a pretty big net to catch some small fish,
but we *do* regularly forget to properly export symbols that
were supposed to be exported.
This time sd_bus_get_current and some renamed symbols are caught.
We want to emphasize bus connections as per-thread communication
primitives, hence introduce a concept of a per-thread default bus, and
make use of it everywhere.
Try to emphasize a bit that there should be a mapping between event
loops and threads, hence introduce a logic that there's one "default"
event loop for each thread, that can be queried via
"sd_event_default()".
The sd-event APIs should be available only as part of libsystemd-bus so
that the utility calls are not linked into each independently and we can
minimize the number of libraries we have.
Old static libsystemd-bus.la becomes libsystemd-bus-internal.la.
memfd functions are also exported in the same library.
(Best viewed with --color-words -U0).
