[PVFS-developers] pvfs-lib cleanup/sanity checking

[Porter Don]

Hey guys,

I came across some cases where the fdesc structure has pointers to memory
that are not being explicitly freed in iodcomm.c and mgrcomm.c.  The fn_p
pointer was also not being initialized to NULL in all cases.  

It turns out that there is an overlying semantic that reserved entries in
pfds[] should not have those members.  That being said, this patch is really
more code clean up and sanity checking than anything else.  It ensures,
unless there is a case I missed, that fdesc's are always memset to zero and
that part_p and fn_p are always freed if they are non-null.  Also, if a
reserved fd has either of these fields, an error message is printed out.  It
seems that this would be helpful in catching bugs in this code if there were
future changes that broke this semantic.

Thoughts?

Don