Some doubious code in pgstat.c

Hello.

While updating a patch, I noticed that the replication slot stats
patch (9868167500) put some somewhat doubious codes.

In pgstat_recv_replslot, an assertion like the following exists:

> idx = pgstat_replslot_index(msg->m_slotname, !msg->m_drop);
..
> Assert(idx >= 0 && idx < max_replication_slots);

But the idx should be 0..(max_replication_slots - 1).

In the same function the following code assumes that the given "char
*name" has the length of NAMEDATALEN. It actually is, but that
assumption seems a bit bogus. I think it should use strlcpy instead.

>pgstat_replslot_index(const char *name, bool create_it)
...
> memcpy(&replSlotStats[nReplSlotStats].slotname, name, NAMEDATALEN);

regards.

--
Kyotaro Horiguchi
NTT Open Source Software Center