windows-smb-logoff-or-abandonment-detection-20060121

windows-smb-logoff-or-abandonment-detection-20060121

This patch:

(1) removes the rest of the dead logoff code that was originally
    stripped of any meaning by DELTA
    winnt-win2000-win98-afs-client-updates-20010623.

(2) gives new meaning to smb_TokenTransfer and smb_TokenTransferTimeout.
    these variables now control how long a smb_username_t and its
    associated cm_user_t and its cm_cellinfo_t (including tokens)
    will be preserved after a logoff.

(3) adds logic to detect logoff conditions

(4) adds cm_CheckVCs().  This function probes the SMB client with a ECHO
    response to determine if the associated SMB virtual circuit is still
    valid.   This is executed once every five minutes by smb_Daemon()
    and whenever the machine's IP addresses change.  This allows
    abandoned VCs to be detected and the associated user credentials,
    file handles, and locks to be cleaned up.  This will also prevent
    the exhaustion of the limited number of SMB sessions.

====================
This delta was composed from multiple commits as part of the CVS->Git migration.
The checkin message with each commit was inconsistent.
The following are the additional commit messages.
====================

and remember to mark the session dead so it can be re-used