mirror of
				https://github.com/python/cpython.git
				synced 2025-11-04 03:44:55 +00:00 
			
		
		
		
	
		
			
				
	
	
		
			77 lines
		
	
	
	
		
			2.1 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			77 lines
		
	
	
	
		
			2.1 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 test.support as support
 | 
						|
_thread = support.import_module('_thread')
 | 
						|
 | 
						|
LONGSLEEP = 2
 | 
						|
SHORTSLEEP = 0.5
 | 
						|
NUM_THREADS = 4
 | 
						|
 | 
						|
class ForkWait(unittest.TestCase):
 | 
						|
 | 
						|
    def setUp(self):
 | 
						|
        self.alive = {}
 | 
						|
        self.stop = 0
 | 
						|
 | 
						|
    def f(self, id):
 | 
						|
        while not self.stop:
 | 
						|
            self.alive[id] = os.getpid()
 | 
						|
            try:
 | 
						|
                time.sleep(SHORTSLEEP)
 | 
						|
            except IOError:
 | 
						|
                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))
 | 
						|
 | 
						|
    @support.reap_threads
 | 
						|
    def test_wait(self):
 | 
						|
        for i in range(NUM_THREADS):
 | 
						|
            _thread.start_new(self.f, (i,))
 | 
						|
 | 
						|
        time.sleep(LONGSLEEP)
 | 
						|
 | 
						|
        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
 | 
						|
            try:
 | 
						|
                self.wait_impl(cpid)
 | 
						|
            finally:
 | 
						|
                # Tell threads to die
 | 
						|
                self.stop = 1
 |