CID 1269841 Out-of-bounds access (OVERRUN)
Correct issue. If the string being concatingated fills the remaining
buffer then a \0 is written past the end of the string. In practice
this should never happen but it should be fixed. I re-organized the
code a bit to clear this error.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>