msg: drop old instead of new messages on overflow

It did that because there was no other way. It used a lock-free ring
buffer, which does not support this. Use a "manual" ring buffer with
explicit locks instead, and drop messages from the start.

(We could have continued to use mp_ring, but it was already too late,
and although mp_ring is fine, using it for types other than bytes looked
awkward, and writing a ring buffer yet again seemed nicer. At least it's
not C++, where mp_ring would have been a template, and everything would
have looked like shit soup no matter what.)

0 files changed, 0 insertions, 0 deletions