As follow-up to the rework of thread-handling, likewise also
the implementation base for locking was switched over from direct
usage of POSIX primitives to the portable wrappers available in
the C++ standard library. All usages have been reviewed and
modernised to prefer λ-functions where possible.
With this series of changes, the old threadpool implementation
and a lot of further low-level support facilities are not used
any more and can be dismantled. Due to the integration efforts
spurred by the »Playback Vertical Slice«, several questions of
architecture could be decided over the last months. The design
of the Scheduler and Engine turned out different than previously
anticipated; notably the Scheduler now covers a wider array of
functionality, including some asynchronous messaging. This has
ramifications for the organisation of work tasks and threads,
and leads to a more deterministic memory management. Resource
management will be done on a higher level, partially superseding
some of the concepts from the early phase of the Lumiera project.
* tmpbuf got its own implementation files
* Some optimizations on the tmpbuf implementation, handling tiny,
small and huge allocations better.
* tiny allocation smaller than sizeof(void*) are not aligned
* Reduced the ring sizes to 16 (configureable in tmpbuf.h)
This is only the tmpbuf refactoring, fixes following on the next
commits.
lumiera_free() is for now just a static inline wraper around free()
Later this makes it easier to hook in some resource managing functions
or a Garbage Collector in.
Replaced all current uses of free()
tmpbuf_tr takes an input string and 2 sets of characters plus a
default character. It produces a output string with all
characters from the first set translated to the correspondending
character in the 2nd set, similar to the shell 'tr' util.
