class TestReadWriteLock(TestCase):
def setUp(self):
self.lock = ReadWriteLock()
self.readers = 0
self.writer_active = False
self.exceptions = dict()
def reset(self):
self.exceptions = dict()
def test_error_on_release_unheld_lock(self):
try:
self.lock.release()
assert False
except ValueError:
pass
def timeout_writer(self, timeout=1):
try:
for tries in range(1, 10):
self.lock.acquireRead(timeout=timeout, blocking=False) # get a read
for tries in range(1, 10):
self.lock.acquireWrite(timeout=timeout, blocking=False) # upgrade to write
self.lock.acquireWrite(blocking=True) # get it twice...
print "thread (writer): %s starting" % current_thread().name
self.writer_active = True
sleep(1)
except Exception, ex:
self.exceptions[current_thread().name] = ex
finally:
class TestReadWriteLock(TestCase):
def setUp(self):
self.lock = ReadWriteLock()
self.readers = 0
self.writer_active = False
self.exceptions = dict()
def reset(self):
self.exceptions = dict()
def test_error_on_release_unheld_lock(self):
try:
self.lock.release()
assert False
except ValueError:
pass
def timeout_writer(self, timeout=1):
try:
for tries in range(1, 10):
self.lock.acquireRead(timeout=timeout,
blocking=False) # get a read
for tries in range(1, 10):
self.lock.acquireWrite(timeout=timeout,
blocking=False) # upgrade to write
self.lock.acquireWrite(blocking=True) # get it twice...
print "thread (writer): %s starting" % current_thread().name
self.writer_active = True
sleep(1)
except Exception, ex:
self.exceptions[current_thread().name] = ex
finally:
class TestReadWriteLock(TestCase):
def setUp(self):
self.lock = ReadWriteLock()
self.readers = 0
self.writer_active = False
self.exceptions = dict()
def reset(self):
self.exceptions = dict()
def test_error_on_release_unheld_lock(self):
try:
self.lock.release()
assert False
except ValueError:
pass
def timeout_writer(self, timeout=1):
try:
for tries in range(1, 10):
self.lock.acquireRead(timeout=timeout, blocking=False) # get a read
for tries in range(1, 10):
self.lock.acquireWrite(timeout=timeout, blocking=False) # upgrade to write
self.lock.acquireWrite(blocking=True) # get it twice...
print("thread (writer): %s starting" % current_thread().name)
self.writer_active = True
sleep(1)
except Exception as ex:
self.exceptions[current_thread().name] = ex
finally:
try:
self.lock.release()
except ValueError: # ignore double release error
pass
self.writer_active = False
print("thread: %s exiting" % current_thread().name)
def timeout_reader(self, to_wait_for, timeout=1):
try:
self.lock.acquireRead(timeout=timeout)
assert not self.writer_active
print("thread (reader): %s starting" % current_thread().name)
self.readers += 1
while to_wait_for - self.readers > 0:
assert not self.writer_active
print("waiting for %d more readers" % (to_wait_for - self.readers))
sleep(0.1)
except Exception as ex:
self.exceptions[current_thread().name] = ex
finally:
try:
self.lock.release()
except ValueError: # ignore double release error
pass
print("thread (reader): %s exiting" % current_thread().name)
def writer(self):
try:
with self.lock.writelock:
print("thread (writer): %s starting" % current_thread().name)
self.writer_active = True
self.lock.acquireRead(timeout=0.1) # make sure we can get a readlock as a writer
sleep(1)
self.writer_active = False
print("thread: %s exiting" % current_thread().name)
except Exception as ex:
self.exceptions[current_thread().name] = ex
finally:
try:
self.lock.release()
except ValueError: # ignore double release error
pass
def reader(self, to_wait_for):
try:
with self.lock.readlock:
assert not self.writer_active
print("thread (reader): %s starting" % current_thread().name)
self.readers += 1
while to_wait_for - self.readers > 0:
assert not self.writer_active
print("waiting for %d more readers" % (to_wait_for - self.readers))
sleep(0.1)
print("thread (reader): %s exiting" % current_thread().name)
except Exception as ex:
self.exceptions[current_thread().name] = ex
def _raise(self, t):
assert not t.isAlive()
if t.name in self.exceptions:
raise self.exceptions[t.name]
def _rww(self, timeout=1, to_wait_for=2):
try:
self.lock.acquireRead(timeout=timeout)
self.readers += 1
while to_wait_for - self.readers > 0:
pass
self.lock.acquireWrite(timeout=timeout)
self.lock.acquireWrite(timeout=timeout)
except Exception as ex:
self.exceptions[current_thread().name] = ex
def test_unthreaded(self):
try:
self.lock.acquireRead(timeout=0.01)
self.lock.acquireWrite(timeout=0.01)
self.lock.acquireRead(timeout=0.01)
self.lock.acquireWrite(timeout=0.01)
except Exception as ex:
raise ex
finally:
try:
self.lock.release()
except:
pass
def test_deadlock(self):
self.reset()
try:
w = []
for i in range(0, 10):
w.append(Thread(target=self._rww, name="w%s" % i))
for i in range(0, 10):
w[i].start()
for i in range(0, 10):
w[i].join()
for i in range(0, 10):
self._raise(w[i])
assert False
except ValueError as ex:
pass
def test_2_readers_and_3_writers(self):
self.reset()
w1 = Thread(target=self.writer, name="w1")
w2 = Thread(target=self.writer, name="w2")
w3 = Thread(target=self.timeout_writer, name="w3", args=[0.01])
r1 = Thread(target=self.reader, name="r1", args=[2])
r2 = Thread(target=self.reader, name="r2", args=[2])
w1.start()
r1.start()
w2.start()
w3.start()
r2.start()
w1.join(timeout=60)
self._raise(w1)
r1.join(timeout=60)
self._raise(r1)
r2.join(timeout=60)
self._raise(r2)
w2.join(timeout=60)
w3.join(timeout=60)
try:
self._raise(w3)
assert False
except ValueError:
pass
except RuntimeError:
pass
class TestReadWriteLock(TestCase):
def setUp(self):
self.lock = ReadWriteLock()
self.readers = 0
self.writer_active = False
self.exceptions = dict()
def reset(self):
self.exceptions = dict()
def test_error_on_release_unheld_lock(self):
try:
self.lock.release()
assert False
except ValueError:
pass
def timeout_writer(self, timeout=1):
try:
for tries in range(1, 10):
self.lock.acquireRead(timeout=timeout, blocking=False) # get a read
for tries in range(1, 10):
self.lock.acquireWrite(timeout=timeout, blocking=False) # upgrade to write
self.lock.acquireWrite(blocking=True) # get it twice...
print("thread (writer): %s starting" % current_thread().name)
self.writer_active = True
sleep(1)
except Exception as ex:
self.exceptions[current_thread().name] = ex
finally:
try:
self.lock.release()
except ValueError: # ignore double release error
pass
self.writer_active = False
print("thread: %s exiting" % current_thread().name)
def timeout_reader(self, to_wait_for, timeout=1):
try:
self.lock.acquireRead(timeout=timeout)
assert(not self.writer_active)
print("thread (reader): %s starting" % current_thread().name)
self.readers += 1
while to_wait_for - self.readers > 0:
assert(not self.writer_active)
print("waiting for %d more readers" % (to_wait_for - self.readers))
sleep(0.1)
except Exception as ex:
self.exceptions[current_thread().name] = ex
finally:
try:
self.lock.release()
except ValueError: # ignore double release error
pass
print("thread (reader): %s exiting" % current_thread().name)
def writer(self):
try:
with self.lock.writelock:
print("thread (writer): %s starting" % current_thread().name)
self.writer_active = True
self.lock.acquireRead(timeout=0.1) # make sure we can get a readlock as a writer
sleep(1)
self.writer_active = False
print("thread: %s exiting" % current_thread().name)
except Exception as ex:
self.exceptions[current_thread().name] = ex
finally:
try:
self.lock.release()
except ValueError: # ignore double release error
pass
def reader(self, to_wait_for):
try:
with self.lock.readlock:
assert(not self.writer_active)
print("thread (reader): %s starting" % current_thread().name)
self.readers += 1
while to_wait_for - self.readers > 0:
assert(not self.writer_active)
print("waiting for %d more readers" % (to_wait_for - self.readers))
sleep(0.1)
print("thread (reader): %s exiting" % current_thread().name)
except Exception as ex:
self.exceptions[current_thread().name] = ex
def _raise(self, t):
assert (not t.isAlive())
if t.name in self.exceptions:
raise self.exceptions[t.name]
def _rww(self, timeout=1, to_wait_for=2):
try:
self.lock.acquireRead(timeout=timeout)
self.readers += 1
while to_wait_for - self.readers > 0:
pass
self.lock.acquireWrite(timeout=timeout)
self.lock.acquireWrite(timeout=timeout)
except Exception as ex:
self.exceptions[current_thread().name] = ex
def test_unthreaded(self):
try:
self.lock.acquireRead(timeout=0.01)
self.lock.acquireWrite(timeout=0.01)
self.lock.acquireRead(timeout=0.01)
self.lock.acquireWrite(timeout=0.01)
except Exception as ex:
raise ex
finally:
try:
self.lock.release()
except:
pass
def test_deadlock(self):
self.reset()
try:
w = []
for i in range(0, 10):
w.append(Thread(target=self._rww, name="w%s" % i))
for i in range(0, 10):
w[i].start()
for i in range(0, 10):
w[i].join()
for i in range(0, 10):
self._raise(w[i])
assert False
except ValueError as ex:
pass
def test_2_readers_and_3_writers(self):
self.reset()
w1 = Thread(target=self.writer, name="w1")
w2 = Thread(target=self.writer, name="w2")
w3 = Thread(target=self.timeout_writer, name="w3", args=[0.01])
r1 = Thread(target=self.reader, name="r1", args=[2])
r2 = Thread(target=self.reader, name="r2", args=[2])
w1.start()
r1.start()
w2.start()
w3.start()
r2.start()
w1.join(timeout=60)
self._raise(w1)
r1.join(timeout=60)
self._raise(r1)
r2.join(timeout=60)
self._raise(r2)
w2.join(timeout=60)
w3.join(timeout=60)
try:
self._raise(w3)
assert False
except ValueError:
pass
except RuntimeError:
pass