This is a fix for file leak in audit log server caused
by design issue:
Session file descriptors in audit log were opened on demand
when the session event or byte stream chunk was reported.
AuditLog server relied on SessionEnd event to close the
file descriptors associated with the session.
However, when SessionEnd event does not arrive (e.g.
there is a timeout or disconnect), the file descriptors
were not closed. This commit adds periodic clean up
of inactive sessions.
SessionEnd is now used as an optimization measure
to close the files, but is not used as the only
trigger to close files.
Now, inactive idle sessions, will close file descriptors
after periods of inactivity and will reopen the file
descriptors when the session activity resumes.
SessionLogger was not designed to open/close files
multiple times as it was reseting offsets
every time the session files were opened. This
change fixes this condition as well.
