mirror of
				https://github.com/python/cpython.git
				synced 2025-10-26 11:14:33 +00:00 
			
		
		
		
	
		
			
				
	
	
		
			91 lines
		
	
	
	
		
			2.5 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			91 lines
		
	
	
	
		
			2.5 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
| """This test case provides support for checking forking and wait behavior.
 | |
| 
 | |
| To test different wait behavior, override the wait_impl method.
 | |
| 
 | |
| We want fork1() semantics -- only the forking thread survives in the
 | |
| child after a fork().
 | |
| 
 | |
| On some systems (e.g. Solaris without posix threads) we find that all
 | |
| active threads survive in the child after a fork(); this is an error.
 | |
| """
 | |
| 
 | |
| import os, sys, time, unittest
 | |
| import threading
 | |
| import test.support as support
 | |
| 
 | |
| 
 | |
| LONGSLEEP = 2
 | |
| SHORTSLEEP = 0.5
 | |
| NUM_THREADS = 4
 | |
| 
 | |
| class ForkWait(unittest.TestCase):
 | |
| 
 | |
|     def setUp(self):
 | |
|         self._threading_key = support.threading_setup()
 | |
|         self.alive = {}
 | |
|         self.stop = 0
 | |
|         self.threads = []
 | |
| 
 | |
|     def tearDown(self):
 | |
|         # Stop threads
 | |
|         self.stop = 1
 | |
|         for thread in self.threads:
 | |
|             thread.join()
 | |
|         thread = None
 | |
|         self.threads.clear()
 | |
|         support.threading_cleanup(*self._threading_key)
 | |
| 
 | |
|     def f(self, id):
 | |
|         while not self.stop:
 | |
|             self.alive[id] = os.getpid()
 | |
|             try:
 | |
|                 time.sleep(SHORTSLEEP)
 | |
|             except OSError:
 | |
|                 pass
 | |
| 
 | |
|     def wait_impl(self, cpid):
 | |
|         for i in range(10):
 | |
|             # waitpid() shouldn't hang, but some of the buildbots seem to hang
 | |
|             # in the forking tests.  This is an attempt to fix the problem.
 | |
|             spid, status = os.waitpid(cpid, os.WNOHANG)
 | |
|             if spid == cpid:
 | |
|                 break
 | |
|             time.sleep(2 * SHORTSLEEP)
 | |
| 
 | |
|         self.assertEqual(spid, cpid)
 | |
|         self.assertEqual(status, 0, "cause = %d, exit = %d" % (status&0xff, status>>8))
 | |
| 
 | |
|     def test_wait(self):
 | |
|         for i in range(NUM_THREADS):
 | |
|             thread = threading.Thread(target=self.f, args=(i,))
 | |
|             thread.start()
 | |
|             self.threads.append(thread)
 | |
| 
 | |
|         # busy-loop to wait for threads
 | |
|         deadline = time.monotonic() + 10.0
 | |
|         while len(self.alive) < NUM_THREADS:
 | |
|             time.sleep(0.1)
 | |
|             if deadline < time.monotonic():
 | |
|                 break
 | |
| 
 | |
|         a = sorted(self.alive.keys())
 | |
|         self.assertEqual(a, list(range(NUM_THREADS)))
 | |
| 
 | |
|         prefork_lives = self.alive.copy()
 | |
| 
 | |
|         if sys.platform in ['unixware7']:
 | |
|             cpid = os.fork1()
 | |
|         else:
 | |
|             cpid = os.fork()
 | |
| 
 | |
|         if cpid == 0:
 | |
|             # Child
 | |
|             time.sleep(LONGSLEEP)
 | |
|             n = 0
 | |
|             for key in self.alive:
 | |
|                 if self.alive[key] != prefork_lives[key]:
 | |
|                     n += 1
 | |
|             os._exit(n)
 | |
|         else:
 | |
|             # Parent
 | |
|             self.wait_impl(cpid)
 | 
