[tarfile] Difficultis catching an exception

[boblatest at googlemail.com]

Hello,

I'm trying to catch an "EOFError" exception that occurs when reading
truncated tarfile. Here's my routine, and below that the callback
trace. Note that although I'm trying to catch all TarFile exceptions,
the tarfile.EOFError ecxeption, and the global EOFError exception, the
program still falls through and fails.

def query_archive(batch_base):
    arc_name = os.path.join(archive_dir, 'B_'+batch_base+'.tar.bz2')
    sys.stderr.write('Archive: %s ' % arc_name)
    try:
        archive = tarfile.open(arc_name, 'r:bz2')
        members = archive.getmembers()
    except tarfile.TarError, EOFError, tarfile.EOFError:
        sys.stderr.write("corrupt.\n")
        db.execute('UPDATE Archives SET Status=2 WHERE BatchBase=?',
(batch_base, ))
    update_batchinfo(members, batch_base)
    return 0

Archive: f:/wafermap_archive/B_48380.tar.bz2 Traceback (most recent
call last):
  File "./wmap", line 11, in <module>
    task.run(command, args)
  File "/cygdrive/h/wafermaps/wmap_import.py", line 142, in run
    query_archive(batch_base)
  File "/cygdrive/h/wafermaps/wmap_import.py", line 95, in
query_archive
    members = archive.getmembers()
  File "/usr/lib/python2.5/tarfile.py", line 1282, in getmembers
    self._load()        # all members, we first have to
  File "/usr/lib/python2.5/tarfile.py", line 2003, in _load
    tarinfo = self.next()
  File "/usr/lib/python2.5/tarfile.py", line 1809, in next
    self.fileobj.seek(self.offset)
EOFError: compressed file ended before the logical end-of-stream was
detected