def start(self):
for i in range(0, 4):
if (i == 0 or i == 1):
self.resource_list[i] = RCB(id=i, numUnits=1)
if (i == 2):
self.resource_list[i] = RCB(id=i, numUnits=2)
if (i == 3):
self.resource_list[i] = RCB(id=i, numUnits=3)
def __init__(self):
r1 = RCB("R1", 1)
r2 = RCB("R2", 2)
r3 = RCB("R3", 3)
r4 = RCB("R4", 4)
self._resource_list = list()
self._resource_list.append(r1)
self._resource_list.append(r2)
self._resource_list.append(r3)
self._resource_list.append(r4)
def request(self,r:"resource type", k:"number of units requested"):
#print("req called {} {}".format(r,k))
if r < 0 or r > 3:
print("-1", end=' ')
return False
req_RCB = self._RCB_list[r]
available_units = req_RCB.state
running_PCB = self._get_running_proc()
# error check here
if not self._req_error_check(running_PCB,r,k):
print("-1", end=' ')
return False
if available_units >= k:
req_RCB.state = available_units - k
running_PCB.append_resource(RCB(r,k))
# print("resource {} allocated".format(r))
else:
self.ready_list.remove(running_PCB)
self._set_running_proc(self.ready_list.get_all()[0])
req_RCB.waitlist.append((running_PCB,k))
# print("process {} blocked".format(running_PCB.num))
self.scheduler()
return
def init(self) -> int:
print("\n")
self._PCBs = [None for _ in range(Manager._MAX_PCBs)]
self._RCBs = [RCB() for _ in range(Manager._MAX_RCPs)]
self._RL = [SLL() for _ in range(Manager._PRIORITY_LEVELS)]
self._running_process = 0
self._number_of_processes = 1
self._PCBs[0] = PCB()
self._RL[0].push(0)
return self.scheduler()
def release(self,r:"resource type",k:"number of units",op:"replace running proc if not None"= None):
#print("rel called {} {}".format(r,k))
running_proc = self._get_running_proc() if op is None else op
if not self._rel_error_check(running_proc, r, k):
print("-1", end='')
return False
units_freed = running_proc.remove_resource(r,k)
if units_freed == False: return False
# add freed units back to resource
resource = self._RCB_list[r] # THIS RESOURCE IS THE MANAGER RESOURCE
resource.state += units_freed
#print("resource {} released".format(r))
# if item on wait list can be unblocked,
# unblock it by adding to ready list,
# adding resource to process list
# and removing it from wait list
if resource.waitlist != []:
for item in resource.waitlist.copy():
available_units = resource.state
process, units_requested = item[0], item[1]
if available_units >= units_requested:
self.ready_list.append(process)
process.append_resource(RCB(r,units_requested))
resource.state -= units_requested
resource.waitlist.remove(item)
self.scheduler()
def __init__(self):
# do not modify PCB or RCB list
self._PCB_list = PCB_List(DEFAULT_PCBL_SIZE)
self._RCB_list = [RCB(0,1),RCB(1,1),RCB(2,2),RCB(3,3)]
self.ready_list = ReadyList(self._PCB_list[0])
self.current_running_pcb = self._PCB_list[0] # returns pcb, NOT INDEX!
def __init__(self):
self.PCBArray = [PCB(None, 0, 0)] + [None] * (PCB_SIZE - 1)
self.RCBArray = [RCB(i) for i in range(RCB_SIZE)]
self.RL = ReadyList()
self.RL.InsertPCB(self.PCBArray[0], 0)
self.ErrorMode = False