private Reservation UpdateReservation(List <ReservationSlot> participantReply, string userID)
{
Reservation reservation;
if (participantReply.Count > 0)
{
ReservationSlot slot = participantReply[0];
if (!_activeReservations.TryGetValue(slot.ReservationID, out reservation))
{
Log.Show(_userName, "WARN: Could not find reservation " + slot.ReservationID);
return(null);
}
}
else
{
return(null);
}
foreach (ReservationSlot rSlot in participantReply)
{
if (rSlot.State == ReservationSlotState.ABORTED)
{
AbortReservationSlot(GetSlot(reservation, rSlot.SlotID), false);
} //if
} //foreach
reservation.Replied.Add(userID);
return(reservation);
}
private void PrepareCommitOrBookNextSlot(Reservation res, int slotID)
{
Monitor.Enter(_calendar[slotID]);
CalendarSlot calendarSlot = _calendar[slotID];
ReservationSlot slot = GetSlot(res, slotID);
if (calendarSlot.Locked || calendarSlot.State == CalendarSlotState.ASSIGNED || (calendarSlot.State == CalendarSlotState.BOOKED && res.ReservationID > calendarSlot.ReservationID))
{
Log.Show(_userName, "Booking of slot " + slotID + " of reservation " + res.ReservationID + " failed. Trying to book next slot.");
AbortReservationSlot(slot, true);
Monitor.Exit(_calendar[slotID]);
BookNextSlot(res);
}
else
{
Log.Show(_userName, "Slot " + slotID + " of reservation " + res.ReservationID + " was booked successfully. Starting commit process.");
LockCalendarSlot(res, slot);
Monitor.Exit(_calendar[slotID]);
foreach (string participantID in res.Participants)
{
if (!participantID.Equals(_userName))
{
_msgDispatcher.SendMessage(MessageType.PRE_COMMIT, res.ReservationID, participantID, slot.SlotID);
}
}
}
}
void IBookingService.DoCommit(int resID, int slotID)
{
Log.Show(_userName, "Received Do Commit from initiator for slot " + slotID + " of reservation " + resID + ". Assigning calendar.");
//Fetch reservation and slot objects
Reservation res;
if (!_activeReservations.TryGetValue(resID, out res))
{
Log.Show(_userName, "WARN: Received doCommit from unknown reservation " + resID);
return;
}
ReservationSlot resSlot = GetSlot(res, slotID);
if (resSlot == null)
{
Log.Show(_userName, "WARN: Received do commit request from unknown reservation " + resID);
return;
}
//GET LOCK HERE
Monitor.Enter(_calendar[slotID]);
AssignCalendarSlot(res, resSlot, true);
Monitor.Exit(_calendar[slotID]);
//RELEASE LOCK HERE
res.InitiatorStub.DoCommitReply(resSlot.ReservationID, resSlot.SlotID, _userName, true);
}
private void AbortReservationSlot(ReservationSlot slot, bool locked)
{
Log.Debug(_userName, "Aborting slot " + slot.SlotID + " from reservation " + slot.ReservationID);
if (slot != null)
{
slot.State = ReservationSlotState.ABORTED;
}
//IF NOT LOCKED GET LOCK HERE
if (!locked)
{
Monitor.Enter(_calendar[slot.SlotID]);
}
FreeCalendarSlot(slot);
if (!locked)
{
Monitor.Exit(_calendar[slot.SlotID]);
}
//IF NOT LOCKED RELEASE LOCK HERE
}
/*
* CALENDAR SHOULD BE LOCKED BEFORE CALLING THIS METHOD
*/
private void LockCalendarSlot(Reservation res, ReservationSlot resSlot)
{
//Change calendar and reservation slot states
CalendarSlot calendarSlot = _calendar[resSlot.SlotID];
calendarSlot.Locked = true;
resSlot.State = ReservationSlotState.COMMITTED;
}
/*
* CALENDAR SHOULD BE LOCKED BEFORE CALLING THIS METHOD
*/
private void BookCalendarSlot(Reservation res, ReservationSlot resSlot)
{
CalendarSlot calendarSlot = _calendar[resSlot.SlotID];
calendarSlot.WaitingBook.Remove(resSlot.ReservationID);
res.CurrentSlot = resSlot.SlotID;
calendarSlot.State = CalendarSlotState.BOOKED;
calendarSlot.ReservationID = resSlot.ReservationID;
resSlot.State = ReservationSlotState.TENTATIVELY_BOOKED;
}
void IBookingService.BookSlot(int resID, int slotID)
{
Log.Show(_userName, "Received book request from initiator for slot " + slotID + " of reservation " + resID);
Reservation res;
if (!_activeReservations.TryGetValue(resID, out res))
{
Log.Show(_userName, "WARN: Received book request from unknown reservation " + resID);
return;
}
ReservationSlot resSlot = GetSlotAndAbortPredecessors(res, slotID);
if (resSlot == null)
{
Log.Show(_userName, "WARN: Received book request from unknown reservation " + resID);
return;
}
bool ack;
Monitor.Enter(_calendar[slotID]);
try
{
CalendarSlot calendarSlot = _calendar[slotID];
calendarSlot.WaitingBook.Remove(resID);
ack = !calendarSlot.Locked && (calendarSlot.State == CalendarSlotState.ACKNOWLEDGED || (calendarSlot.State == CalendarSlotState.BOOKED && resID < calendarSlot.ReservationID));
if (ack)
{
BookCalendarSlot(res, resSlot);
}
else
{
AbortReservationSlot(resSlot, true);
}
}
finally
{
Monitor.Exit(_calendar[slotID]);
}
res.InitiatorStub.BookReply(resSlot.ReservationID, resSlot.SlotID, _userName, ack);
}
void IBookingService.PrepareCommit(int resID, int slotID)
{
Log.Show(_userName, "Received prepare commit request from initiator for slot " + slotID + " of reservation " + resID);
//Fetch reservation and slot objects
Reservation res;
if (!_activeReservations.TryGetValue(resID, out res))
{
Log.Show(_userName, "WARN: Received pre-commit request from unknown reservation " + resID);
return;
}
ReservationSlot resSlot = GetSlot(res, slotID);
if (resSlot == null)
{
Log.Show(_userName, "WARN: Received prepare commit request from unknown reservation " + resID);
return;
}
//GET LOCK HERE
Monitor.Enter(_calendar[slotID]);
CalendarSlot calendarSlot = _calendar[slotID];
bool ack = !calendarSlot.Locked && calendarSlot.State == CalendarSlotState.BOOKED && calendarSlot.ReservationID == resID;
if (ack)
{
LockCalendarSlot(res, resSlot);
}
else
{
AbortReservationSlot(resSlot, true);
}
Monitor.Exit(_calendar[slotID]);
//RELEASE LOCK HERE
res.InitiatorStub.PrepareCommitReply(resSlot.ReservationID, resSlot.SlotID, _userName, ack);
}
private void CommitSlot(Reservation res, int slotID)
{
ReservationSlot slot = GetSlot(res, slotID);
Log.Show(_userName, "Slot " + slotID + " of reservation " + res.ReservationID + " was pre-committed successfully. Assigning calendar slot.");
Monitor.Enter(_calendar[slotID]);
AssignCalendarSlot(res, slot, false);
Monitor.Exit(_calendar[slotID]);
foreach (string participantID in res.Participants)
{
if (!participantID.Equals(_userName))
{
_msgDispatcher.SendMessage(MessageType.DO_COMMIT, res.ReservationID, participantID, slot.SlotID);
}
}
}
//Verify calendar slots and create reservation states
private List <ReservationSlot> CreateReservationSlots(ReservationRequest req, int resID)
{
List <ReservationSlot> reservationSlots = new List <ReservationSlot>();
foreach (int slot in req.Slots)
{
ReservationSlotState state = ReservationSlotState.INITIATED;
CalendarSlot calendarSlot;
if (_calendar.TryGetValue(slot, out calendarSlot))
{
if (calendarSlot.State == CalendarSlotState.ASSIGNED)
{
state = ReservationSlotState.ABORTED;
}
}
else
{
calendarSlot = new CalendarSlot();
calendarSlot.SlotNum = slot;
calendarSlot.State = CalendarSlotState.FREE;
_calendar[slot] = calendarSlot;
Log.Debug(_userName, "Creating new calendar entry. Slot: " + calendarSlot.SlotNum + ". State: " + calendarSlot.State);
}
Monitor.Enter(calendarSlot);
if (calendarSlot.State == CalendarSlotState.FREE)
{
calendarSlot.State = CalendarSlotState.ACKNOWLEDGED;
}
Monitor.Exit(calendarSlot);
calendarSlot.WaitingBook.Add(resID);
ReservationSlot rs = new ReservationSlot(resID, slot, state);
reservationSlots.Add(rs);
}
return(reservationSlots);
}
private bool CollectReply(int resID, int slotID, string userID, bool ack, out Reservation res)
{
if (!_activeReservations.TryGetValue(resID, out res))
{
Log.Show(_userName, "WARN: Received reply from unknown reservation " + resID);
return(false);
}
if (res.CurrentSlot == slotID)
{
ReservationSlot slot = GetSlot(res, slotID);
Monitor.Enter(slot);
if (ack)
{
Monitor.Exit(slot);
res.Replied.Add(userID);
if (res.Replied.Count == (res.Participants.Count - 1))
{
res.Replied.Clear();
return(true);
}
}
else if (slot.State != ReservationSlotState.ABORTED)
{
AbortReservationSlot(slot, false);
Monitor.Exit(slot);
_msgDispatcher.ClearMessages(res.Participants, resID);
res.Replied.Clear();
BookNextSlot(res);
}
else
{
Monitor.Exit(slot);
}
return(false);
}
return(false);
}
/*
* CALENDAR SHOULD BE LOCKED BEFORE CALLING THIS METHOD
*/
private void AssignCalendarSlot(Reservation res, ReservationSlot resSlot, bool clean)
{
//Change calendar and reservation slot states
CalendarSlot calendarSlot = _calendar[resSlot.SlotID];
calendarSlot.State = CalendarSlotState.ASSIGNED;
calendarSlot.ReservationID = res.ReservationID;
calendarSlot.Participants = res.Participants;
calendarSlot.Description = res.Description;
foreach (ReservationSlot slot in res.Slots)
{
if (slot != resSlot && slot.State != ReservationSlotState.ABORTED)
{
AbortReservationSlot(slot, true);
}
}
if (clean)
{
CleanReservation(res);
}
}
private void FreeCalendarSlot(ReservationSlot slot)
{
CalendarSlot cSlot = _calendar[slot.SlotID];
cSlot.WaitingBook.Remove(slot.ReservationID);
if (cSlot.State == CalendarSlotState.ACKNOWLEDGED && cSlot.WaitingBook.Count == 0)
{
cSlot.State = CalendarSlotState.FREE;
}
else if (cSlot.State == CalendarSlotState.BOOKED && cSlot.ReservationID == slot.ReservationID)
{
if (cSlot.WaitingBook.Count > 0)
{
cSlot.State = CalendarSlotState.ACKNOWLEDGED;
}
else
{
cSlot.State = CalendarSlotState.FREE;
}
cSlot.Locked = false;
}
}
/*
* CALENDAR SHOULD BE LOCKED BEFORE CALLING THIS METHOD
*/
private void LockCalendarSlot(Reservation res, ReservationSlot resSlot)
{
//Change calendar and reservation slot states
CalendarSlot calendarSlot = _calendar[resSlot.SlotID];
calendarSlot.Locked = true;
resSlot.State = ReservationSlotState.COMMITTED;
}
private void FreeCalendarSlot(ReservationSlot slot)
{
CalendarSlot cSlot = _calendar[slot.SlotID];
cSlot.WaitingBook.Remove(slot.ReservationID);
if (cSlot.State == CalendarSlotState.ACKNOWLEDGED && cSlot.WaitingBook.Count == 0)
{
cSlot.State = CalendarSlotState.FREE;
}
else if (cSlot.State == CalendarSlotState.BOOKED && cSlot.ReservationID == slot.ReservationID)
{
if (cSlot.WaitingBook.Count > 0)
{
cSlot.State = CalendarSlotState.ACKNOWLEDGED;
}
else
{
cSlot.State = CalendarSlotState.FREE;
}
cSlot.Locked = false;
}
}
//Verify calendar slots and create reservation states
private List<ReservationSlot> CreateReservationSlots(ReservationRequest req, int resID)
{
List<ReservationSlot> reservationSlots = new List<ReservationSlot>();
foreach (int slot in req.Slots)
{
ReservationSlotState state = ReservationSlotState.INITIATED;
CalendarSlot calendarSlot;
if (_calendar.TryGetValue(slot, out calendarSlot))
{
if (calendarSlot.State == CalendarSlotState.ASSIGNED)
{
state = ReservationSlotState.ABORTED;
}
}
else
{
calendarSlot = new CalendarSlot();
calendarSlot.SlotNum = slot;
calendarSlot.State = CalendarSlotState.FREE;
_calendar[slot] = calendarSlot;
Log.Debug(_userName, "Creating new calendar entry. Slot: " + calendarSlot.SlotNum + ". State: " + calendarSlot.State);
}
Monitor.Enter(calendarSlot);
if (calendarSlot.State == CalendarSlotState.FREE)
{
calendarSlot.State = CalendarSlotState.ACKNOWLEDGED;
}
Monitor.Exit(calendarSlot);
calendarSlot.WaitingBook.Add(resID);
ReservationSlot rs = new ReservationSlot(resID, slot, state);
reservationSlots.Add(rs);
}
return reservationSlots;
}
/*
* CALENDAR SHOULD BE LOCKED BEFORE CALLING THIS METHOD
*/
private void BookCalendarSlot(Reservation res, ReservationSlot resSlot)
{
CalendarSlot calendarSlot = _calendar[resSlot.SlotID];
calendarSlot.WaitingBook.Remove(resSlot.ReservationID);
res.CurrentSlot = resSlot.SlotID;
calendarSlot.State = CalendarSlotState.BOOKED;
calendarSlot.ReservationID = resSlot.ReservationID;
resSlot.State = ReservationSlotState.TENTATIVELY_BOOKED;
}
/*
* CALENDAR SHOULD BE LOCKED BEFORE CALLING THIS METHOD
*/
private void AssignCalendarSlot(Reservation res, ReservationSlot resSlot, bool clean)
{
//Change calendar and reservation slot states
CalendarSlot calendarSlot = _calendar[resSlot.SlotID];
calendarSlot.State = CalendarSlotState.ASSIGNED;
calendarSlot.ReservationID = res.ReservationID;
calendarSlot.Participants = res.Participants;
calendarSlot.Description = res.Description;
foreach (ReservationSlot slot in res.Slots)
{
if (slot != resSlot && slot.State != ReservationSlotState.ABORTED)
{
AbortReservationSlot(slot, true);
}
}
if (clean)
{
CleanReservation(res);
}
}
private void AbortReservationSlot(ReservationSlot slot, bool locked)
{
Log.Debug(_userName, "Aborting slot " + slot.SlotID + " from reservation " + slot.ReservationID);
if (slot != null)
{
slot.State = ReservationSlotState.ABORTED;
}
//IF NOT LOCKED GET LOCK HERE
if (!locked)
{
Monitor.Enter(_calendar[slot.SlotID]);
}
FreeCalendarSlot(slot);
if (!locked)
{
Monitor.Exit(_calendar[slot.SlotID]);
}
//IF NOT LOCKED RELEASE LOCK HERE
}
