# Test case for the os.poll() function import os import subprocess import random import select import threading import time import unittest from test.support import TESTFN, run_unittest, cpython_only from test.support import threading_helper try: select.poll except AttributeError: raise unittest.SkipTest("select.poll not defined") def find_ready_matching(ready, flag): match = [] for fd, mode in ready: if mode & flag: match.append(fd) return match class PollTests(unittest.TestCase): def test_poll1(self): # Basic functional test of poll object # Create a bunch of pipe and test that poll works with them. p = select.poll() NUM_PIPES = 12 MSG = b" This is a test." MSG_LEN = len(MSG) readers = [] writers = [] r2w = {} w2r = {} for i in range(NUM_PIPES): rd, wr = os.pipe() p.register(rd) p.modify(rd, select.POLLIN) p.register(wr, select.POLLOUT) readers.append(rd) writers.append(wr) r2w[rd] = wr w2r[wr] = rd bufs = [] while writers: ready = p.poll() ready_writers = find_ready_matching(ready, select.POLLOUT) if not ready_writers: raise RuntimeError("no pipes ready for writing") wr = random.choice(ready_writers) os.write(wr, MSG) ready = p.poll() ready_readers = find_ready_matching(ready, select.POLLIN) if not ready_readers: raise RuntimeError("no pipes ready for reading") rd = random.choice(ready_readers) buf = os.read(rd, MSG_LEN) self.assertEqual(len(buf), MSG_LEN) bufs.append(buf) os.close(r2w[rd]) ; os.close( rd ) p.unregister( r2w[rd] ) p.unregister( rd ) writers.remove(r2w[rd]) self.assertEqual(bufs, [MSG] * NUM_PIPES) def test_poll_unit_tests(self): # returns NVAL for invalid file descriptor FD, w = os.pipe() os.close(FD) os.close(w) p = select.poll() p.register(FD) r = p.poll() self.assertEqual(r[0], (FD, select.POLLNVAL)) with open(TESTFN, 'w') as f: fd = f.fileno() p = select.poll() p.register(f) r = p.poll() self.assertEqual(r[0][0], fd) r = p.poll() self.assertEqual(r[0], (fd, select.POLLNVAL)) os.unlink(TESTFN) # type error for invalid arguments p = select.poll() self.assertRaises(TypeError, p.register, p) self.assertRaises(TypeError, p.unregister, p) # can't unregister non-existent object p = select.poll() self.assertRaises(KeyError, p.unregister, 3) # Test error cases pollster = select.poll() class Nope: pass class Almost: def fileno(self): return 'fileno' self.assertRaises(TypeError, pollster.register, Nope(), 0) self.assertRaises(TypeError, pollster.register, Almost(), 0) # Another test case for poll(). This is copied from the test case for # select(), modified to use poll() instead. def test_poll2(self): cmd = 'for i in 0 1 2 3 4 5 6 7 8 9; do echo testing...; sleep 1; done' proc = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE, bufsize=0) proc.__enter__() self.addCleanup(proc.__exit__, None, None, None) p = proc.stdout pollster = select.poll() pollster.register( p, select.POLLIN ) for tout in (0, 1000, 2000, 4000, 8000, 16000) + (-1,)*10: fdlist = pollster.poll(tout) if (fdlist == []): continue fd, flags = fdlist[0] if flags & select.POLLHUP: line = p.readline() if line != b"": self.fail('error: pipe seems to be closed, but still returns data') continue elif flags & select.POLLIN: line = p.readline() if not line: break self.assertEqual(line, b'testing...\n') continue else: self.fail('Unexpected return value from select.poll: %s' % fdlist) def test_poll3(self): # test int overflow pollster = select.poll() pollster.register(1) self.assertRaises(OverflowError, pollster.poll, 1 << 64) x = 2 + 3 if x != 5: self.fail('Overflow must have occurred') # Issues #15989, #17919 self.assertRaises(ValueError, pollster.register, 0, -1) self.assertRaises(OverflowError, pollster.register, 0, 1 << 64) self.assertRaises(ValueError, pollster.modify, 1, -1) self.assertRaises(OverflowError, pollster.modify, 1, 1 << 64) @cpython_only def test_poll_c_limits(self): from _testcapi import USHRT_MAX, INT_MAX, UINT_MAX pollster = select.poll() pollster.register(1) # Issues #15989, #17919 self.assertRaises(OverflowError, pollster.register, 0, USHRT_MAX + 1) self.assertRaises(OverflowError, pollster.modify, 1, USHRT_MAX + 1) self.assertRaises(OverflowError, pollster.poll, INT_MAX + 1) self.assertRaises(OverflowError, pollster.poll, UINT_MAX + 1) @threading_helper.reap_threads def test_threaded_poll(self): r, w = os.pipe() self.addCleanup(os.close, r) self.addCleanup(os.close, w) rfds = [] for i in range(10): fd = os.dup(r) self.addCleanup(os.close, fd) rfds.append(fd) pollster = select.poll() for fd in rfds: pollster.register(fd, select.POLLIN) t = threading.Thread(target=pollster.poll) t.start() try: time.sleep(0.5) # trigger ufds array reallocation for fd in rfds: pollster.unregister(fd) pollster.register(w, select.POLLOUT) self.assertRaises(RuntimeError, pollster.poll) finally: # and make the call to poll() from the thread return os.write(w, b'spam') t.join() @unittest.skipUnless(threading, 'Threading required for this test.') @threading_helper.reap_threads def test_poll_blocks_with_negative_ms(self): for timeout_ms in [None, -1000, -1, -1.0, -0.1, -1e-100]: # Create two file descriptors. This will be used to unlock # the blocking call to poll.poll inside the thread r, w = os.pipe() pollster = select.poll() pollster.register(r, select.POLLIN) poll_thread = threading.Thread(target=pollster.poll, args=(timeout_ms,)) poll_thread.start() poll_thread.join(timeout=0.1) self.assertTrue(poll_thread.is_alive()) # Write to the pipe so pollster.poll unblocks and the thread ends. os.write(w, b'spam') poll_thread.join() self.assertFalse(poll_thread.is_alive()) os.close(r) os.close(w) def test_main(): run_unittest(PollTests) if __name__ == '__main__': test_main()