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1 |
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2 import unittest |
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3 import os |
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4 import tempfile |
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5 import signal |
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6 import threading |
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7 import time |
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8 |
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9 class testLogLock(unittest.TestCase): |
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10 def test_ThreadingAndLocks(self): |
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11 #create a thread, have that thread grab a lock, and sleep. |
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12 fd, file = tempfile.mkstemp('.nonlog') |
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13 _lock = threading.RLock() |
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14 os.close(fd) |
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15 def locker(): |
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16 os.write(fd, 'Thread acquiring lock\n') |
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17 _lock.acquire() |
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18 os.write(fd, 'Thread acquired lock\n') |
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19 time.sleep(0.4) |
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20 os.write(fd, 'Thread releasing lock\n') |
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21 _lock.release() |
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22 os.write(fd, 'Thread released lock\n') |
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23 |
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24 #Then in the main thread, throw a signal to self |
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25 def handleSignal(sigNum, frame): |
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26 os.write(fd, 'Main Thread acquiring lock\n') |
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27 lock = False |
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28 endtime = time.time() + 1.0 |
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29 while not lock: |
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30 lock = _lock.acquire(blocking=0) |
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31 time.sleep(0.01) |
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32 if time.time() > endtime: |
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33 break |
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34 if not lock: |
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35 os.write(fd, 'Main Thread could not acquire lock\n') |
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36 return |
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37 os.write(fd, 'Main Thread acquired lock\n') |
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38 os.write(fd, 'Main Thread releasing lock\n') |
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39 _lock.release() |
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40 os.write(fd, 'Main Thread released lock\n') |
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41 |
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42 sighndlr = signal.signal(signal.SIGUSR1, handleSignal) |
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43 try: |
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44 fd = os.open(file, os.O_SYNC | os.O_WRONLY | os.O_CREAT) |
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45 thread = threading.Thread(target=locker) |
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46 thread.start() |
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47 time.sleep(0.1) |
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48 os.kill(os.getpid(), signal.SIGUSR1) |
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49 thread.join() |
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50 |
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51 #check the results |
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52 os.close(fd) |
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53 fileconts = open(file, 'r').read() |
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54 self.assertTrue('Main Thread released lock' in fileconts) |
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55 self.assertEqual(fileconts, |
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56 '''Thread acquiring lock |
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57 Thread acquired lock |
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58 Main Thread acquiring lock |
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59 Thread releasing lock |
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60 Thread released lock |
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61 Main Thread acquired lock |
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62 Main Thread releasing lock |
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63 Main Thread released lock |
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64 ''') |
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65 |
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66 #Now try after acquiring the lock from the main thread |
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67 fd = os.open(file, os.O_SYNC | os.O_WRONLY | os.O_CREAT) |
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68 _lock.acquire() |
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69 thread = threading.Thread(target=locker) |
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70 thread.start() |
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71 time.sleep(0.1) |
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72 os.kill(os.getpid(), signal.SIGUSR1) |
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73 _lock.release() |
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74 thread.join() |
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75 os.close(fd) |
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76 fileconts = open(file, 'r').read() |
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77 self.assertEqual(fileconts, |
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78 '''Thread acquiring lock |
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79 Main Thread acquiring lock |
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80 Main Thread acquired lock |
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81 Main Thread releasing lock |
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82 Main Thread released lock |
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83 Thread acquired lock |
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84 Thread releasing lock |
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85 Thread released lock |
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86 ''') |
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87 |
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88 finally: |
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89 signal.signal(signal.SIGUSR1, sighndlr) |
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90 try: |
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91 os.close(fd) |
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92 except OSError: |
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93 pass |
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94 try: |
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95 os.unlink(file) |
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96 except OSError: |
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97 pass |
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98 |