Should make janet a bit easier to use. Also changes the
header to not expose the size of native mutexes and rwlocks, except
with janet_os_mutex_size and janet_os_rwlock_size.
Note that this is a work in progress and simply a first attempt at
getting some code into place before being able to test it. This code
follows of sorts both the poll and epoll sections of the codebase hoping
to achieve the exact same.
Some pointer casting with abstract types was incorrect, resulting
in strange behavior when trying to use supervisor channels that were
threaded. This fix also adds the ability to supply a supervisor channel
directly when creating a thread.
Introduces close semtantics to channels as well, but otherwise
threaded channels behave much like non-threaded channels. They have
different marshalling behavior though, and can only send values over by
packing and unpacking them. For now, this means only primitive values
although this will be expanded.
Also missing some implementation for closing threaded channels, and a
whole lot of testing. Achtung!, Caveat emptor, here be dragons and bugs.
janet_loop1_interrupt makes the event loop compatible
with safe interruptions for custom scheduling. Does this by exposing
custom events on the event loop. A custom event schedules a function pointer
to run in a way that can interrupt
epoll_wait/poll/GetQueuedCompletionStatus.
This would allow an embedder to suspend the current Janet fiber
via an external event like a signal, other thread, or really anything.
This is a useful primitive for custom schedulers that would call
janet_interpreter_interupt periodically (say, in an interval with SIG_ALRM),
do some work, and then use janet_continue on the janet_root_fiber, or
for embedding into other soft-realtime applications like a game. To say,
only allow about 5ms per frame of interpreter time.
This is mainly meant for use as the entry point to a C wrapper for a
janet program. This maeans the programmer doesn't need to use an ifdef
to handle if the event loop is enabled.
