Given a feedback log which has a touch log, but where that touch log is empty, mtreplay will fail with the following error:

Traceback (most recent call last):
  File "/usr/bin/mtreplay", line 79, in <module>
    main(sys.argv)
  File "/usr/bin/mtreplay", line 65, in main
    log = Log(args[0])
  File "/mnt/host/source/src/platform/mttools/mtlib/log.py", line 45, in Log
    return FeedbackLog(source)
  File "/mnt/host/source/src/platform/mttools/mtlib/log.py", line 148, in __init__
    self._ExtractLogFiles()
  File "/mnt/host/source/src/platform/mttools/mtlib/log.py", line 254, in _ExtractLogFiles
    logs = ExtractByInterface('pad') + ExtractByInterface('screen')
  File "/mnt/host/source/src/platform/mttools/mtlib/log.py", line 211, in ExtractByInterface
    activity_tar_file = tarfile.open(fileobj=StringIO(activity_tar_data))
  File "/usr/lib64/python2.7/tarfile.py", line 1672, in open
    raise ReadError("file could not be opened successfully")
tarfile.ReadError: file could not be opened successfully

Instead, it should alert the user that there is an empty file, and continue.