def customer(shared, cid):
barber = Semaphore(0)
while True:
sleep(randint(9, 10) / 100)
shared.mutex.lock()
if shared.customers == shared.N:
balk(cid)
shared.mutex.unlock()
continue
print(f"customer {cid} wait for...")
shared.queue.append(barber)
shared.customers += 1
shared.mutex.unlock()
shared.customer.signal()
barber.wait()
getHairCut(cid)
shared.customerDone.signal()
shared.barberDone.wait()
shared.mutex.lock()
shared.customers -= 1
shared.mutex.unlock()
class SimpleBarrier:
def __init__(self, n):
self.N = n
self.counter = 0
self.mutex = Mutex()
self.turnstile = Semaphore(0)
def wait(self):
self.mutex.lock()
self.counter += 1
if self.counter == self.N:
self.counter = 0
self.turnstile.signal(self.N)
self.mutex.unlock()
self.turnstile.wait()
class SimpleBarrier:
def __init__(self, N):
self.N = N
self.C = 0
self.M = Mutex()
self.T = Semaphore(0)
def wait(self):
self.M.lock()
self.C += 1
if self.C == self.N:
self.C = 0 # posledne vlakno nastavi pocitadlo na nulu
self.T.signal(self.N) # uvolni N vlakien
self.M.unlock()
self.T.wait()
class Barrier:
def __init__(self, N):
self.N = N
self.mutex = Mutex()
self.counter = 0
self.semaphore = Semaphore(0)
def wait(self):
self.mutex.lock()
self.counter += 1
if self.counter == self.N:
self.counter = 0
self.semaphore.signal(self.N)
self.mutex.unlock()
self.semaphore.wait()
class SimpleBarrier:
def __init__(self, N):
self.N = N
self.C = 0
self.M = Mutex()
self.T = Semaphore(0)
def wait(self):
self.M.lock()
self.C += 1
if self.C == self.N:
self.C = 0
self.T.signal(self.N)
self.M.unlock()
self.T.wait()
class SimpleBarrier():
def __init__(self, N):
self.mutex = Mutex()
self.capacity = N
self.counter = 0
self.sem = Semaphore()
def wait(self):
self.mutex.lock()
self.counter += 1
if self.counter == self.capacity:
print(f'Lod zakotvila s posadkou {self.counter} ludi')
self.counter = 0
self.sem.signal(self.capacity)
self.mutex.unlock()
self.sem.wait()
class SimpleBarrier:
def __init__(self, num_of_threads):
self.N = num_of_threads
self.cnt = 0
self.mutex = Mutex()
self.turnstile = Semaphore(0)
def wait(self):
self.mutex.lock()
self.cnt += 1
if self.cnt == self.N:
self.cnt = 0
for _ in range(self.N):
self.turnstile.signal()
self.mutex.unlock()
self.turnstile.wait()
class SimpleBarrier:
def __init__(self, N):
self.N = N
self.C = 0
self.M = Mutex()
self.T = Semaphore(0)
def wait(self, savage_id, barrier_id):
self.M.lock()
self.C += 1
print(f'savage {savage_id} before barrier {barrier_id}, {self.C} present')
if self.C == self.N:
print(f'savage {savage_id} opening barrier {barrier_id}')
self.C = 0 # posledne vlakno nastavi pocitadlo na nulu
self.T.signal(self.N) # uvolni N vlakien
self.M.unlock()
self.T.wait()
class SimpleBarrier:
def __init__(self, n):
self.N = n
self.counter = 0
self.mutex = Mutex()
self.turnstile = Semaphore(0)
def wait(self, each=None, last=None):
self.mutex.lock()
self.counter += 1
if each:
print(each)
if self.counter == self.N:
self.counter = 0
if last:
print(last)
self.turnstile.signal(self.N)
self.mutex.unlock()
self.turnstile.wait()
class SimpleBarrier:
def __init__(self, N):
self.N = N
self.mutex = Mutex()
self.cnt = 0
self.sem = Semaphore(0)
def wait(self, print_str, id, print_last=False, print_each=False):
self.mutex.lock()
self.cnt += 1
if print_each:
print(print_str.format(id, self.cnt))
if self.cnt == self.N:
self.cnt = 0
if print_last:
print(print_str.format(id))
self.sem.signal(self.N)
self.mutex.unlock()
self.sem.wait()
class PowerPlant:
def __init__(self):
self.barrier = Barrier(3)
self.monitor_ls = LightSwitch()
self.sensor_ls = LightSwitch()
self.no_sensors = Semaphore(1)
self.no_monitors = Semaphore(1)
def monitor(self, monitor_id):
while True:
self.barrier.event.wait()
self.no_monitors.wait()
number_of_monitors_reading = self.monitor_ls.lock(self.no_sensors)
self.no_monitors.signal()
duration = randint(40, 50) / 1000
print('monit "%02d": '
'pocet_citajucich_monitorov=%02d, '
'trvanie_citania=%03d\n' %
(monitor_id, number_of_monitors_reading, duration*1000))
sleep(duration)
self.monitor_ls.unlock(self.no_sensors)
def sensor(self, sensor_id, duration):
while True:
sleep(randint(50, 60) / 1000)
number_of_sensors_writing = self.sensor_ls.lock(self.no_monitors)
self.no_sensors.wait()
print('cidlo "%02d": '
'pocet_zapisujucich_cidiel=%02d, '
'trvanie_zapisu=%03d\n' %
(sensor_id, number_of_sensors_writing, duration * 1000))
sleep(duration)
self.no_sensors.signal()
self.barrier.wait_with_events()
self.sensor_ls.unlock(self.no_monitors)
class SimpleBarrier:
def __init__(self, N):
self.N = N # pocet vlaken, ktore budu cakat
self.counter = 0 # premenna, ktora rata pocet vlaken, co cakaju
self.mutex = Semaphore(
1) # Semaphor inicializovany na 1 je to iste co Mutex
self.barriera = Semaphore(0) #
def barrier(self):
# vlakno prislo ku bariere, zvys counter ze prislo
# v jednom case moze inkrementovat counter iba jedno vlakno
self.mutex.wait()
self.counter += 1
self.mutex.signal()
# ak prisli vsetky vlakna k bariere otvor ju a pusti prveho...
# to co dojde posledne aj prve vyjde (?)
if self.counter == self.N:
self.barriera.signal()
# inak budu vlakna cakat
self.barriera.wait()
# pustene vlakno pusti dalsie
self.barriera.signal()
class Barrier(object):
def __init__(self, N):
self.N = N
self.cnt = 0
self.mutex = Mutex()
self.b1 = Semaphore(0)
self.b2 = Semaphore(0)
def wait(self):
self.mutex.lock()
self.cnt += 1
if self.cnt == self.N:
print("------")
self.b1.signal(self.N)
self.mutex.unlock()
self.b1.wait()
self.mutex.lock()
self.cnt -= 1
if self.cnt == 0:
self.b2.signal(self.N)
self.mutex.unlock()
self.b2.wait()
class SimpleBarrier:
def __init__(self, N):
self.N = N
self.mutex = Mutex()
self.cnt = 0
self.sem = Semaphore(0)
def wait(self,
print_str,
savage_id,
print_last_thread=False,
print_each_thread=False):
self.mutex.lock()
self.cnt += 1
if print_each_thread:
print(print_str % (savage_id, self.cnt))
if self.cnt == self.N:
self.cnt = 0
if print_last_thread:
print(print_str % (savage_id))
self.sem.signal(self.N)
self.mutex.unlock()
self.sem.wait()
class Shared(object):
def __init__(self):
self.mutex = Semaphore(1)
self.oxygenCount = 0
self.hydrogenCount = 0
self.oxyQueue = Semaphore(1)
self.hydroQueue = Semaphore(2)
self.barrier = Barrier(3)
def oxygen(self):
"""sleep na simulovanie náhodného príchodu atómov"""
sleep(randint(1, 10) / 10)
"""
spoločný semafor, na ktorom atómy čakajú
a vstupujú po jednom a zvýšenie počídla, keďže vstupujú
po jednom, tak nepotrebujeme už nijak chrániť prístup k
premennej oxygenCount.
"""
self.mutex.wait()
self.oxygenCount += 1
print("Oxygen count = ", self.oxygenCount)
"""
podmienka, ktora overuje, či je aj dostatok atómov
na tvorbu molekuly vody, ak nie je, tak pusti ďalší
atóm cez semafor, inak spraví zlúčenie.
"""
if self.hydrogenCount < 2:
self.mutex.signal()
else:
self.oxygenCount -= 1
self.hydrogenCount -= 2
self.oxyQueue.signal()
self.hydroQueue.signal(2)
print("bonding")
print("count after bond: oxygen: %d, hydrogen: %d\n" %
(self.oxygenCount, self.hydrogenCount))
"""
Kyslík čaká, kým mu prídu dva vodíky, cez prejde
len jeden.
"""
self.oxyQueue.wait()
"""
Bariera, ktorá pusti cez 3 prvky, aby nenastalo, že nejaký
prvok sa stihne obehnúť
"""
self.barrier.wait()
"""
Po úšpešnom spojení nastane, kyslík otvorí semafor pre
ďalší prvok aby nenastal deadlock.
"""
self.mutex.signal()
def hydrogen(self):
"""sleep na simulovanie náhodného príchodu atómov"""
sleep(randint(1, 10) / 10)
"""
spoločný semafor, na ktorom atómy čakajú
a vstupujú po jednom a zvýšenie počídla, keďže vstupujú
po jednom, tak nepotrebujeme už nijak chrániť prístup k
premennej hydrogenCount.
"""
self.mutex.wait()
self.hydrogenCount += 1
print("Hydrogen count = ", self.hydrogenCount)
"""
podmienka, ktora overuje, či je aj dostatok atómov
na tvorbu molekuly vody a kyslíka, ak nie je, tak pustí
ďalší atóm cez semafor, inak spraví zlúčenie.
"""
if self.hydrogenCount < 2 or self.oxygenCount < 1:
self.mutex.signal()
else:
self.oxygenCount -= 1
self.hydrogenCount -= 2
self.oxyQueue.signal()
self.hydroQueue.signal(2)
print("bonding")
print("count after bond: oxygen: %d, hydrogen: %d\n" %
(self.oxygenCount, self.hydrogenCount))
"""
Vodík čaká, kým mu príde ďalší vodík a kyslík,
cez prejdu dva.
"""
self.hydroQueue.wait()
"""
Bariera, ktorá pusti cez 3 prvky, aby nenastalo, že nejaký
prvok sa stihne obehnúť.
"""
self.barrier.wait()
class Molecule:
def __init__(self):
# binarny semafor
self.mutex = Semaphore(1)
self.oxygenQueue = Semaphore(0)
self.hydrogenQueue = Semaphore(0)
self.oxygen = 0
self.hydrogen = 0
self.barrier = Barrier(3)
def oxygenFunc(self):
# zamadzenie pristupu do KO
self.mutex.wait()
self.oxygen += 1
"""
Ak je este nedostatocny pocet vodikov
tak chod dalej a uvolni pridanie
sa dalsiemu kysliku
"""
if self.hydrogen < 2:
self.mutex.signal()
else:
self.oxygen -= 1
self.hydrogen -= 2
# odobera sa kyslik z "fronty"
self.oxygenQueue.signal()
# odoberaju sa 2 vodiky z "fronty"
self.hydrogenQueue.signal(2)
# Pridava sa jeden kyslik do "fronty"
self.oxygenQueue.wait()
print("oxygen do zlucenia")
# zlucovanie
self.bond()
"""
bariera, kde sa caka na dobehnutie
vsetkych 3 atomov po zluceni, aby
sa mohli ist dalsie atomy zlucovat
"""
self.barrier.wait()
self.mutex.signal()
def hydrogenFunc(self):
# zamadzenie pristupu do KO
self.mutex.wait()
self.hydrogen += 1
"""
Ak je nedostatocny pocet kyslikov alebo vodikov
tak uvolni pridanie sa dalsiemu vodiku a chood
dalej
"""
if self.hydrogen < 2 or self.oxygen < 1:
self.mutex.signal()
else:
self.oxygen -= 1
self.hydrogen -= 2
# odobera sa kyslik z "fronty"
self.oxygenQueue.signal()
# odoberaju sa 2 vodiky z "fronty"
self.hydrogenQueue.signal(2)
# Pridava sa vodik do zlucenia
self.hydrogenQueue.wait()
print("Hydrogen do zlucenia")
# zlucovanie
self.bond()
"""
bariera, kde sa caka na dobehnutie
vsetkych 3 atomov po zluceni, aby
sa mohli ist dalsie atomy zlucovat
"""
self.barrier.wait()
def bond(self):
# prevedenie zlucovania
sleep(randint(5, 15) / 10)
print("Zlucenie buniek")
