TriNet Trigger Coordinator `tc'

Trigger Coordinator receives input in the form of Event and Trigger
signals. It attempts to associate events and triggers, writes the associations
to the database and notifies other modules of the triggers.

Trigger Coordinator processes input whenever it receives it from SmartSocket
connections. It also processes known events on a time schedule. To facilitate
the processing schedule, Trigger Coordinator maintains an EventList (list of
EventAssoc objects; see below) in order of their next-due processing time,
soonest due event at top of the list.

The input CMS messages consists only of the event ID (from Event Coordinator)
or trigger ID (from trig2db); the Event and Trigger information are then
obtained from the database.

On event signal arrival:
    Get Event info from database
    For all known EventAssocs in state Trig_Only, find first event for which
    this new event falls within the TimeWindow "matchtime".
    if found, associate new event with this trigger: {
        Remove EventAssoc from EventList
	Set tc wakeuptime to that of first EventAssoc on EventList
	Write association to database in AssocNtE table (evid, trigid, auth,
	  subsource, wfflag = TRUE).
	Send AssocEvent signal.
	For each EventAssoc in state Event_Only, find ones "contained" in this
	  trigger. Contained means an event origin time falls within the
	  EventAssoc's TimeWindow "conttime"
	If found {
	    Remove this event from EventList
	    Set tc wakeuptime to that of first EventAssoc on EventList
	    Write association to database in AssocNtE table (evid, trigid, 
	      auth, subsource, wfflag = FALSE).
	    no AssocEvent signal needed; it has already been sent(?)
	}
    }
    else {
        Create new EventAssoc structure for this event.
	Set EventAssoc curstate = Event_Only
	set EventAssoc timeout = origin time + MaxTrigDuration + MaxProcDuration
	Insert (timeout, EventAssoc) pair into EventList
	Set tc wakeuptime to that of first EventAssoc on EventList
    }

On trigger signal arrival:
    Get Trigger info from database NetTrig and trig_channel tables
    Set matchtime TimeWindow: start is earliest station trigger start -
      PreTrigBuf; end is earlier of latest station window end, matchtime.start + AssocDur
    Set conttime TimeWindow: start is earliest station trigger start -
      PreTrigBuf; end is latest station window end time.
    For all events in state Event_Only, find events that fall within this
      trigger's matchtime window.
    If found {
        Pull EventAssoc from EventList
	Set tc wakeuptime to that of first EventAssoc on EventList
	Write association to database in AssocNtE table (evid, trigid, auth,
	  subsource, wfflag = TRUE).
	Send AssocEvent signal.
	For each EventAssoc in state Event_Only, find ones "contained" in this
	  trigger. Contained means an event origin time falls within the
	  EventAssoc's TimeWindow "conttime"
	If found {
	    Remove this event from EventList
	    Set tc wakeuptime to that of first EventAssoc on EventList
	    Write association to database in AssocNtE table (evid, trigid, auth,
	      subsource, wfflag = FALSE).
	    no AssocEvent signal needed; it has already been sent(?)
	}
    }
    else {
        Create new EventAssoc structure for this trigger.
	Set EventAssoc curstate = Trig_Only
	set EventAssoc timeout = subnet trigger time + AssocDur + EcFinalDur +
	    MaxProcDur 
	Insert (timeout, EventAssoc) pair into EventList
	Set tc wakeuptime to that of first EventAssoc on EventList
    }

On EventAssoc timeout:
    Remove EventAssoc from EventList
    switch (curstate) {   no "drop-through" from one case to next.
    Trig_Only:
        Create event for this trigger {
	    Set Origin.locevid = trigger ID
	    Set Origin.timedate = trigger time
	    Set Origin location to bogus
	    Get new evid from database sequence
	    Write event info to database tables Event, Origin
	    Write association to database in AssocNtE table (evid, trigid, auth,
	      subsource, wfflag = TRUE).
	    Send UnassocTrig signal.
	    For each EventAssoc in state Event_Only, find ones "contained" in this
	      trigger. Contained means an event origin time falls within the
	      EventAssoc's TimeWindow "conttime"
	    If found {
	        Remove this event from EventList
		Set tc wakeuptime to that of first EventAssoc on EventList
		Write association to database in AssocNtE table (evid, trigid, auth,
		  subsource, wfflag = FALSE).
		no AssocEvent signal needed; it has already been sent(?) 
	    }
        }
    Event_Only:
        Send UnassocEvent Signal (event not associated with a trigger)
    }


Major Data Structures:
EventList:	map< TimeStamp, EventAssoc >
EventAssoc:	trigState curstate,
		Event event,
		NetworkTrigger trig,
		TimeWindow matchtime
		TimeWindow conttime
Event:		unsigned long evid,
		eventType etype,
		char *comment,
		char *source,
		char *subsource,
		OriginList origins,
		int select,
OriginList:	list< Origin >
Origin:		unsigned long orid,
		char *locevid,
		char *algorithm,
		char *source,
		char *subsource,
		TimeStamp origdate,
		double latitude,
		double longitude,
		double depth,
		etc...
		MagList mags,
		ChanArrivalList arrivals,
		ChanAmpList amps,
		ChanCodaList codas

NetworkTrigger:	unsigned long trigid,
		char *source,
		char *subsource,
		char *locid,
		char *algorithm,
		TimeStamp trigdate;
		int all_chans,
		TimeWindow savewin,
		TriggerList trigs
TriggerList:	map< Channel, Trigger >
Trigger:	unsigned long trigid,
		trigType trigflag,
		TimeStamp trigtime,
		TimeWindow savewin

		
Major Enumeration Types:
trigState:	Error, Trig_Only, Event_Only, Assoc
trigType:	Trig, Member