/Lib/bsddb/test/test_lock.py

  1"""
  2TestCases for testing the locking sub-system.
  3"""
  4
  5import time
  6
  7import unittest
  8from test_all import db, test_support, verbose, have_threads, \
  9        get_new_environment_path, get_new_database_path
 10
 11if have_threads :
 12    from threading import Thread
 13    import sys
 14    if sys.version_info[0] < 3 :
 15        from threading import currentThread
 16    else :
 17        from threading import current_thread as currentThread
 18
 19#----------------------------------------------------------------------
 20
 21class LockingTestCase(unittest.TestCase):
 22    import sys
 23    if sys.version_info[:3] < (2, 4, 0):
 24        def assertTrue(self, expr, msg=None):
 25            self.failUnless(expr,msg=msg)
 26
 27
 28    def setUp(self):
 29        self.homeDir = get_new_environment_path()
 30        self.env = db.DBEnv()
 31        self.env.open(self.homeDir, db.DB_THREAD | db.DB_INIT_MPOOL |
 32                                    db.DB_INIT_LOCK | db.DB_CREATE)
 33
 34
 35    def tearDown(self):
 36        self.env.close()
 37        test_support.rmtree(self.homeDir)
 38
 39
 40    def test01_simple(self):
 41        if verbose:
 42            print '\n', '-=' * 30
 43            print "Running %s.test01_simple..." % self.__class__.__name__
 44
 45        anID = self.env.lock_id()
 46        if verbose:
 47            print "locker ID: %s" % anID
 48        lock = self.env.lock_get(anID, "some locked thing", db.DB_LOCK_WRITE)
 49        if verbose:
 50            print "Aquired lock: %s" % lock
 51        self.env.lock_put(lock)
 52        if verbose:
 53            print "Released lock: %s" % lock
 54        self.env.lock_id_free(anID)
 55
 56
 57    def test02_threaded(self):
 58        if verbose:
 59            print '\n', '-=' * 30
 60            print "Running %s.test02_threaded..." % self.__class__.__name__
 61
 62        threads = []
 63        threads.append(Thread(target = self.theThread,
 64                              args=(db.DB_LOCK_WRITE,)))
 65        threads.append(Thread(target = self.theThread,
 66                              args=(db.DB_LOCK_READ,)))
 67        threads.append(Thread(target = self.theThread,
 68                              args=(db.DB_LOCK_READ,)))
 69        threads.append(Thread(target = self.theThread,
 70                              args=(db.DB_LOCK_WRITE,)))
 71        threads.append(Thread(target = self.theThread,
 72                              args=(db.DB_LOCK_READ,)))
 73        threads.append(Thread(target = self.theThread,
 74                              args=(db.DB_LOCK_READ,)))
 75        threads.append(Thread(target = self.theThread,
 76                              args=(db.DB_LOCK_WRITE,)))
 77        threads.append(Thread(target = self.theThread,
 78                              args=(db.DB_LOCK_WRITE,)))
 79        threads.append(Thread(target = self.theThread,
 80                              args=(db.DB_LOCK_WRITE,)))
 81
 82        for t in threads:
 83            import sys
 84            if sys.version_info[0] < 3 :
 85                t.setDaemon(True)
 86            else :
 87                t.daemon = True
 88            t.start()
 89        for t in threads:
 90            t.join()
 91
 92    def test03_lock_timeout(self):
 93        self.env.set_timeout(0, db.DB_SET_LOCK_TIMEOUT)
 94        self.env.set_timeout(0, db.DB_SET_TXN_TIMEOUT)
 95        self.env.set_timeout(123456, db.DB_SET_LOCK_TIMEOUT)
 96        self.env.set_timeout(7890123, db.DB_SET_TXN_TIMEOUT)
 97
 98        def deadlock_detection() :
 99            while not deadlock_detection.end :
100                deadlock_detection.count = \
101                    self.env.lock_detect(db.DB_LOCK_EXPIRE)
102                if deadlock_detection.count :
103                    while not deadlock_detection.end :
104                        pass
105                    break
106                time.sleep(0.01)
107
108        deadlock_detection.end=False
109        deadlock_detection.count=0
110        t=Thread(target=deadlock_detection)
111        import sys
112        if sys.version_info[0] < 3 :
113            t.setDaemon(True)
114        else :
115            t.daemon = True
116        t.start()
117        self.env.set_timeout(100000, db.DB_SET_LOCK_TIMEOUT)
118        anID = self.env.lock_id()
119        anID2 = self.env.lock_id()
120        self.assertNotEqual(anID, anID2)
121        lock = self.env.lock_get(anID, "shared lock", db.DB_LOCK_WRITE)
122        start_time=time.time()
123        self.assertRaises(db.DBLockNotGrantedError,
124                self.env.lock_get,anID2, "shared lock", db.DB_LOCK_READ)
125        end_time=time.time()
126        deadlock_detection.end=True
127        self.assertTrue((end_time-start_time) >= 0.0999)
128        self.env.lock_put(lock)
129        t.join()
130
131        self.env.lock_id_free(anID)
132        self.env.lock_id_free(anID2)
133
134        if db.version() >= (4,6):
135            self.assertTrue(deadlock_detection.count>0)
136
137    def theThread(self, lockType):
138        import sys
139        if sys.version_info[0] < 3 :
140            name = currentThread().getName()
141        else :
142            name = currentThread().name
143
144        if lockType ==  db.DB_LOCK_WRITE:
145            lt = "write"
146        else:
147            lt = "read"
148
149        anID = self.env.lock_id()
150        if verbose:
151            print "%s: locker ID: %s" % (name, anID)
152
153        for i in xrange(1000) :
154            lock = self.env.lock_get(anID, "some locked thing", lockType)
155            if verbose:
156                print "%s: Aquired %s lock: %s" % (name, lt, lock)
157
158            self.env.lock_put(lock)
159            if verbose:
160                print "%s: Released %s lock: %s" % (name, lt, lock)
161
162        self.env.lock_id_free(anID)
163
164
165#----------------------------------------------------------------------
166
167def test_suite():
168    suite = unittest.TestSuite()
169
170    if have_threads:
171        suite.addTest(unittest.makeSuite(LockingTestCase))
172    else:
173        suite.addTest(unittest.makeSuite(LockingTestCase, 'test01'))
174
175    return suite
176
177
178if __name__ == '__main__':
179    unittest.main(defaultTest='test_suite')