1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
|
# Very rudimentary test of threading module
import test.test_support
from test.test_support import verbose
import random
import threading
import thread
import time
import unittest
# A trivial mutable counter.
class Counter(object):
def __init__(self):
self.value = 0
def inc(self):
self.value += 1
def dec(self):
self.value -= 1
def get(self):
return self.value
class TestThread(threading.Thread):
def __init__(self, name, testcase, sema, mutex, nrunning):
threading.Thread.__init__(self, name=name)
self.testcase = testcase
self.sema = sema
self.mutex = mutex
self.nrunning = nrunning
def run(self):
delay = random.random() * 2
if verbose:
print('task', self.getName(), 'will run for', delay, 'sec')
self.sema.acquire()
self.mutex.acquire()
self.nrunning.inc()
if verbose:
print(self.nrunning.get(), 'tasks are running')
self.testcase.assert_(self.nrunning.get() <= 3)
self.mutex.release()
time.sleep(delay)
if verbose:
print('task', self.getName(), 'done')
self.mutex.acquire()
self.nrunning.dec()
self.testcase.assert_(self.nrunning.get() >= 0)
if verbose:
print(self.getName(), 'is finished.', self.nrunning.get(), \
'tasks are running')
self.mutex.release()
self.sema.release()
class ThreadTests(unittest.TestCase):
# Create a bunch of threads, let each do some work, wait until all are
# done.
def test_various_ops(self):
# This takes about n/3 seconds to run (about n/3 clumps of tasks,
# times about 1 second per clump).
NUMTASKS = 10
# no more than 3 of the 10 can run at once
sema = threading.BoundedSemaphore(value=3)
mutex = threading.RLock()
numrunning = Counter()
threads = []
for i in range(NUMTASKS):
t = TestThread("<thread %d>"%i, self, sema, mutex, numrunning)
threads.append(t)
t.start()
if verbose:
print('waiting for all tasks to complete')
for t in threads:
t.join(NUMTASKS)
self.assert_(not t.isAlive())
if verbose:
print('all tasks done')
self.assertEqual(numrunning.get(), 0)
# run with a small(ish) thread stack size (256kB)
def test_various_ops_small_stack(self):
if verbose:
print('with 256kB thread stack size...')
try:
threading.stack_size(262144)
except thread.error:
if verbose:
print('platform does not support changing thread stack size')
return
self.test_various_ops()
threading.stack_size(0)
# run with a large thread stack size (1MB)
def test_various_ops_large_stack(self):
if verbose:
print('with 1MB thread stack size...')
try:
threading.stack_size(0x100000)
except thread.error:
if verbose:
print('platform does not support changing thread stack size')
return
self.test_various_ops()
threading.stack_size(0)
def test_foreign_thread(self):
# Check that a "foreign" thread can use the threading module.
def f(mutex):
# Acquiring an RLock forces an entry for the foreign
# thread to get made in the threading._active map.
r = threading.RLock()
r.acquire()
r.release()
mutex.release()
mutex = threading.Lock()
mutex.acquire()
tid = thread.start_new_thread(f, (mutex,))
# Wait for the thread to finish.
mutex.acquire()
self.assert_(tid in threading._active)
self.assert_(isinstance(threading._active[tid],
threading._DummyThread))
del threading._active[tid]
# PyThreadState_SetAsyncExc() is a CPython-only gimmick, not (currently)
# exposed at the Python level. This test relies on ctypes to get at it.
def test_PyThreadState_SetAsyncExc(self):
try:
import ctypes
except ImportError:
if verbose:
print("test_PyThreadState_SetAsyncExc can't import ctypes")
return # can't do anything
set_async_exc = ctypes.pythonapi.PyThreadState_SetAsyncExc
class AsyncExc(Exception):
pass
exception = ctypes.py_object(AsyncExc)
# `worker_started` is set by the thread when it's inside a try/except
# block waiting to catch the asynchronously set AsyncExc exception.
# `worker_saw_exception` is set by the thread upon catching that
# exception.
worker_started = threading.Event()
worker_saw_exception = threading.Event()
class Worker(threading.Thread):
def run(self):
self.id = thread.get_ident()
self.finished = False
try:
while True:
worker_started.set()
time.sleep(0.1)
except AsyncExc:
self.finished = True
worker_saw_exception.set()
t = Worker()
t.setDaemon(True) # so if this fails, we don't hang Python at shutdown
t.start()
if verbose:
print(" started worker thread")
# Try a thread id that doesn't make sense.
if verbose:
print(" trying nonsensical thread id")
result = set_async_exc(ctypes.c_long(-1), exception)
self.assertEqual(result, 0) # no thread states modified
# Now raise an exception in the worker thread.
if verbose:
print(" waiting for worker thread to get started")
worker_started.wait()
if verbose:
print(" verifying worker hasn't exited")
self.assert_(not t.finished)
if verbose:
print(" attempting to raise asynch exception in worker")
result = set_async_exc(ctypes.c_long(t.id), exception)
self.assertEqual(result, 1) # one thread state modified
if verbose:
print(" waiting for worker to say it caught the exception")
worker_saw_exception.wait(timeout=10)
self.assert_(t.finished)
if verbose:
print(" all OK -- joining worker")
if t.finished:
t.join()
# else the thread is still running, and we have no way to kill it
def test_main():
test.test_support.run_unittest(ThreadTests)
if __name__ == "__main__":
test_main()
|