Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 1 | """This test case provides support for checking forking and wait behavior. |
| 2 | |
| 3 | To test different wait behavior, overrise the wait_impl method. |
| 4 | |
| 5 | We want fork1() semantics -- only the forking thread survives in the |
| 6 | child after a fork(). |
| 7 | |
| 8 | On some systems (e.g. Solaris without posix threads) we find that all |
| 9 | active threads survive in the child after a fork(); this is an error. |
| 10 | |
| 11 | While BeOS doesn't officially support fork and native threading in |
| 12 | the same application, the present example should work just fine. DC |
| 13 | """ |
| 14 | |
| 15 | import os, sys, time, thread, unittest |
| 16 | from test.test_support import TestSkipped |
| 17 | |
| 18 | LONGSLEEP = 2 |
| 19 | SHORTSLEEP = 0.5 |
| 20 | NUM_THREADS = 4 |
| 21 | |
| 22 | class ForkWait(unittest.TestCase): |
| 23 | |
| 24 | def setUp(self): |
| 25 | self.alive = {} |
| 26 | self.stop = 0 |
| 27 | |
| 28 | def f(self, id): |
| 29 | while not self.stop: |
| 30 | self.alive[id] = os.getpid() |
| 31 | try: |
| 32 | time.sleep(SHORTSLEEP) |
| 33 | except IOError: |
| 34 | pass |
| 35 | |
| 36 | def wait_impl(self, cpid): |
Thomas Wouters | 0e3f591 | 2006-08-11 14:57:12 +0000 | [diff] [blame] | 37 | for i in range(10): |
| 38 | # waitpid() shouldn't hang, but some of the buildbots seem to hang |
| 39 | # in the forking tests. This is an attempt to fix the problem. |
| 40 | spid, status = os.waitpid(cpid, os.WNOHANG) |
| 41 | if spid == cpid: |
| 42 | break |
| 43 | time.sleep(2 * SHORTSLEEP) |
| 44 | |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 45 | self.assertEquals(spid, cpid) |
| 46 | self.assertEquals(status, 0, "cause = %d, exit = %d" % (status&0xff, status>>8)) |
| 47 | |
| 48 | def test_wait(self): |
| 49 | for i in range(NUM_THREADS): |
| 50 | thread.start_new(self.f, (i,)) |
| 51 | |
| 52 | time.sleep(LONGSLEEP) |
| 53 | |
Guido van Rossum | cc2b016 | 2007-02-11 06:12:03 +0000 | [diff] [blame] | 54 | a = sorted(self.alive.keys()) |
Guido van Rossum | 805365e | 2007-05-07 22:24:25 +0000 | [diff] [blame^] | 55 | self.assertEquals(a, list(range(NUM_THREADS))) |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 56 | |
| 57 | prefork_lives = self.alive.copy() |
| 58 | |
| 59 | if sys.platform in ['unixware7']: |
| 60 | cpid = os.fork1() |
| 61 | else: |
| 62 | cpid = os.fork() |
| 63 | |
| 64 | if cpid == 0: |
| 65 | # Child |
| 66 | time.sleep(LONGSLEEP) |
| 67 | n = 0 |
| 68 | for key in self.alive: |
| 69 | if self.alive[key] != prefork_lives[key]: |
| 70 | n += 1 |
| 71 | os._exit(n) |
| 72 | else: |
| 73 | # Parent |
| 74 | self.wait_impl(cpid) |
| 75 | # Tell threads to die |
| 76 | self.stop = 1 |
| 77 | time.sleep(2*SHORTSLEEP) # Wait for threads to die |