In blist.h, BLIST_BMAP_RADIX and BLIST_META_RADIX have the same
value. There's no longer a need for both names, so rename them both to
BLIST_RADIX. Simplify formulas that compute with both of them, and
rewrite comments that describe them.
Make a similar change for BLIST_BMAP_MASK and BLIST_META_MASK.
In blist_create, modify the use of the variable radix so that it takes
on values 1, 64, 4096, ... instead of 64, 4096, 262144, ..., in order
to avoid overflow when the next power of 64 greater that blocks is too
big to represent. The value of bl->bl_radix is similarly reduced by a
factor of BLIST_RADIX.
Change the blist_meta_* functions that take a radix parameter to
handle one reduced by a factor of BLIST_RADIX. When necessary, handle
overflows in masking off all but the first radix*BLIST_RADIX bits of a
number, when that's masking off all the bits.
Fix compiler warnings in blist test code. Add a test for blist_create
failure to the blist test code. Change the blist_test code size
parameter to allow for larger test cases.
Remove from swaponsomething the checks for overflow in the blist
code. The only failure I can think of is from a failed malloc.