MFC r299764,r299765,r299767,r299769,r299770,r299774,r299802,r299803,r299805,r299814:

r299764:

Use the size of the destination buffer, not the source buffer.

Technically this is a no-op, but mute the clang warning in case the malloc call
above for fstring ever changes in the future

r299765:

Fix theoretical buffer overflow issues in snmp_oid2asn_oid

Increase the size of string by 1 to account for the '\0' terminator. In the event
that str doesn't contain any non-alpha chars, i would be set to MAXSTR, and
the subsequent strlcpy call would overflow by a character.

Remove unnecessary string[i] = '\0' -- this is already handled by strlcpy.

r299767:

Mute sign compare warning by casting rc to u_int to match nbindings' type

rc cannot be negative -- that was already tested for earlier on in
the function

r299769:

Use the size of the destination buffer instead of the malloc size, repeated, in order
to mute a -Wstrlcpy-strlcat-size warning

r299770:

Fix up r299764

I meant to use nitems, not sizeof(..) with the destination buffer. Using sizeof(..)
on a pointer will always truncate the output in the destination buffer incorrectly

Pointyhat to: ngie

r299774:

Do minimal work necessary to cure a -Wunused-but-set-variable warning from gcc

How errno is saved before and restored after strtoul calls needs a rethink

r299802:

Fix up both r299764 and r299770

nitems was wrong too, as it was being tested against a pointer instead of a buffer on
the stack.

Since the old code was just doing malloc, then strlcpy'ing the contents of the source
buffer into the destination buffer, replace it all with a call to strdup..

Supersized Duncecap to: ngie

r299803:

Replace malloc + memset(.., 0, ..) with calloc calls

r299805:

Fix up r299769

Similar to r299802, it was noted that using nitems on scalar pointers is
invalid.

Use strdup instead of malloc + strlcpy (which is what the old code was doing
anyhow).

Pointyhat to: ngie

r299814:

Replace malloc + memset(.., 0, ..) with calloc calls