diff options
Diffstat (limited to 'Lib')
| -rw-r--r-- | Lib/test/lock_tests.py | 32 | ||||
| -rw-r--r-- | Lib/threading.py | 24 |
2 files changed, 47 insertions, 9 deletions
diff --git a/Lib/test/lock_tests.py b/Lib/test/lock_tests.py index 23a02e0b4e..888586840f 100644 --- a/Lib/test/lock_tests.py +++ b/Lib/test/lock_tests.py @@ -663,6 +663,38 @@ class BaseSemaphoreTests(BaseTestCase): b.wait_for_finished() self.assertEqual(sem_results, [True] * (6 + 7 + 6 + 1)) + def test_multirelease(self): + sem = self.semtype(7) + sem.acquire() + results1 = [] + results2 = [] + phase_num = 0 + def f(): + sem.acquire() + results1.append(phase_num) + sem.acquire() + results2.append(phase_num) + b = Bunch(f, 10) + b.wait_for_started() + while len(results1) + len(results2) < 6: + _wait() + self.assertEqual(results1 + results2, [0] * 6) + phase_num = 1 + sem.release(7) + while len(results1) + len(results2) < 13: + _wait() + self.assertEqual(sorted(results1 + results2), [0] * 6 + [1] * 7) + phase_num = 2 + sem.release(6) + while len(results1) + len(results2) < 19: + _wait() + self.assertEqual(sorted(results1 + results2), [0] * 6 + [1] * 7 + [2] * 6) + # The semaphore is still locked + self.assertFalse(sem.acquire(False)) + # Final release, to let the last thread finish + sem.release() + b.wait_for_finished() + def test_try_acquire(self): sem = self.semtype(2) self.assertTrue(sem.acquire(False)) diff --git a/Lib/threading.py b/Lib/threading.py index 32a3d7c303..c3bbb19acb 100644 --- a/Lib/threading.py +++ b/Lib/threading.py @@ -439,16 +439,19 @@ class Semaphore: __enter__ = acquire - def release(self): - """Release a semaphore, incrementing the internal counter by one. + def release(self, n=1): + """Release a semaphore, incrementing the internal counter by one or more. When the counter is zero on entry and another thread is waiting for it to become larger than zero again, wake up that thread. """ + if n < 1: + raise ValueError('n must be one or more') with self._cond: - self._value += 1 - self._cond.notify() + self._value += n + for i in range(n): + self._cond.notify() def __exit__(self, t, v, tb): self.release() @@ -475,8 +478,8 @@ class BoundedSemaphore(Semaphore): Semaphore.__init__(self, value) self._initial_value = value - def release(self): - """Release a semaphore, incrementing the internal counter by one. + def release(self, n=1): + """Release a semaphore, incrementing the internal counter by one or more. When the counter is zero on entry and another thread is waiting for it to become larger than zero again, wake up that thread. @@ -485,11 +488,14 @@ class BoundedSemaphore(Semaphore): raise a ValueError. """ + if n < 1: + raise ValueError('n must be one or more') with self._cond: - if self._value >= self._initial_value: + if self._value + n > self._initial_value: raise ValueError("Semaphore released too many times") - self._value += 1 - self._cond.notify() + self._value += n + for i in range(n): + self._cond.notify() class Event: |