arena: catch bad spans containing '0'
authorBarret Rhoden <brho@cs.berkeley.edu>
Fri, 14 Jun 2019 19:07:44 +0000 (15:07 -0400)
committerBarret Rhoden <brho@cs.berkeley.edu>
Thu, 11 Jul 2019 18:29:21 +0000 (14:29 -0400)
commitb9e0b68866d1eefca6d6f6716d2b2a62497c4f59
treea2313cd4fef5ec21d9dabe04f9d8b2ff819a3ec3
parent1b64bce15d420eb72455d3050e7357da1b3096c0
arena: catch bad spans containing '0'

Currently arena's can't hand out the value '0'.  That's actually baked
in to the vmem interface.  NULL is returned on error, so you can't
differentiate between it and 0.  I'm OK with that for now.

The asserts will catch people who try to add a span starting at 0, which
is close enough to catch this problem.

Signed-off-by: Barret Rhoden <brho@cs.berkeley.edu>
kern/src/arena.c