Partially revert r191171, which went too far in trying to eliminate some duplicated code.  In particular, archive_read_open_filename() has different close handling than archive_read_open_fd(), so delegating the former to the latter in the degenerate case (a NULL filename is treated as stdin) broke reading from pipelines.  In particular, this fixes occasional port failures that were seen when using "gunzip | tar" pipelines under /bin/csh.
Partially revert r191171, which went too far in trying
to eliminate some duplicated code.  In particular,
archive_read_open_filename() has different close
handling than archive_read_open_fd(), so delegating
the former to the latter in the degenerate case
(a NULL filename is treated as stdin) broke reading
from pipelines.  In particular, this fixes occasional
port failures that were seen when using "gunzip | tar"
pipelines under /bin/csh.

Thanks to Alexey Shuvaev for reporting this failure and
patiently helping me to track down the cause.

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase