"""Test program for the fcntl C module. """ import multiprocessing import platform import os import struct import sys import unittest from test.support import verbose, cpython_only, get_pagesize from test.support.import_helper import import_module from test.support.os_helper import TESTFN, unlink # Skip test if no fcntl module. fcntl = import_module('fcntl') class BadFile: def __init__(self, fn): self.fn = fn def fileno(self): return self.fn def try_lockf_on_other_process_fail(fname, cmd): f = open(fname, 'wb+') try: fcntl.lockf(f, cmd) except BlockingIOError: pass finally: f.close() def try_lockf_on_other_process(fname, cmd): f = open(fname, 'wb+') fcntl.lockf(f, cmd) fcntl.lockf(f, fcntl.LOCK_UN) f.close() class TestFcntl(unittest.TestCase): def setUp(self): self.f = None def tearDown(self): if self.f and not self.f.closed: self.f.close() unlink(TESTFN) @staticmethod def get_lockdata(): try: os.O_LARGEFILE except AttributeError: start_len = "ll" else: start_len = "qq" if (sys.platform.startswith(('netbsd', 'freebsd', 'openbsd')) or sys.platform == 'darwin'): if struct.calcsize('l') == 8: off_t = 'l' pid_t = 'i' else: off_t = 'lxxxx' pid_t = 'l' lockdata = struct.pack(off_t + off_t + pid_t + 'hh', 0, 0, 0, fcntl.F_WRLCK, 0) elif sys.platform.startswith('gnukfreebsd'): lockdata = struct.pack('qqihhi', 0, 0, 0, fcntl.F_WRLCK, 0, 0) elif sys.platform in ['hp-uxB', 'unixware7']: lockdata = struct.pack('hhlllii', fcntl.F_WRLCK, 0, 0, 0, 0, 0, 0) else: lockdata = struct.pack('hh'+start_len+'hh', fcntl.F_WRLCK, 0, 0, 0, 0, 0) if lockdata: if verbose: print('struct.pack: ', repr(lockdata)) return lockdata def test_fcntl_fileno(self): # the example from the library docs self.f = open(TESTFN, 'wb') rv = fcntl.fcntl(self.f.fileno(), fcntl.F_SETFL, os.O_NONBLOCK) if verbose: print('Status from fcntl with O_NONBLOCK: ', rv) lockdata = self.get_lockdata() rv = fcntl.fcntl(self.f.fileno(), fcntl.F_SETLKW, lockdata) if verbose: print('String from fcntl with F_SETLKW: ', repr(rv)) self.f.close() def test_fcntl_file_descriptor(self): # again, but pass the file rather than numeric descriptor self.f = open(TESTFN, 'wb') rv = fcntl.fcntl(self.f, fcntl.F_SETFL, os.O_NONBLOCK) if verbose: print('Status from fcntl with O_NONBLOCK: ', rv) lockdata = self.get_lockdata() rv = fcntl.fcntl(self.f, fcntl.F_SETLKW, lockdata) if verbose: print('String from fcntl with F_SETLKW: ', repr(rv)) self.f.close() def test_fcntl_bad_file(self): with self.assertRaises(ValueError): fcntl.fcntl(-1, fcntl.F_SETFL, os.O_NONBLOCK) with self.assertRaises(ValueError): fcntl.fcntl(BadFile(-1), fcntl.F_SETFL, os.O_NONBLOCK) with self.assertRaises(TypeError): fcntl.fcntl('spam', fcntl.F_SETFL, os.O_NONBLOCK) with self.assertRaises(TypeError): fcntl.fcntl(BadFile('spam'), fcntl.F_SETFL, os.O_NONBLOCK) @cpython_only def test_fcntl_bad_file_overflow(self): from _testcapi import INT_MAX, INT_MIN # Issue 15989 with self.assertRaises(OverflowError): fcntl.fcntl(INT_MAX + 1, fcntl.F_SETFL, os.O_NONBLOCK) with self.assertRaises(OverflowError): fcntl.fcntl(BadFile(INT_MAX + 1), fcntl.F_SETFL, os.O_NONBLOCK) with self.assertRaises(OverflowError): fcntl.fcntl(INT_MIN - 1, fcntl.F_SETFL, os.O_NONBLOCK) with self.assertRaises(OverflowError): fcntl.fcntl(BadFile(INT_MIN - 1), fcntl.F_SETFL, os.O_NONBLOCK) @unittest.skipIf( platform.machine().startswith('arm') and platform.system() == 'Linux', "ARM Linux returns EINVAL for F_NOTIFY DN_MULTISHOT") def test_fcntl_64_bit(self): # Issue #1309352: fcntl shouldn't fail when the third arg fits in a # C 'long' but not in a C 'int'. try: cmd = fcntl.F_NOTIFY # This flag is larger than 2**31 in 64-bit builds flags = fcntl.DN_MULTISHOT except AttributeError: self.skipTest("F_NOTIFY or DN_MULTISHOT unavailable") fd = os.open(os.path.dirname(os.path.abspath(TESTFN)), os.O_RDONLY) try: fcntl.fcntl(fd, cmd, flags) finally: os.close(fd) def test_flock(self): # Solaris needs readable file for shared lock self.f = open(TESTFN, 'wb+') fileno = self.f.fileno() fcntl.flock(fileno, fcntl.LOCK_SH) fcntl.flock(fileno, fcntl.LOCK_UN) fcntl.flock(self.f, fcntl.LOCK_SH | fcntl.LOCK_NB) fcntl.flock(self.f, fcntl.LOCK_UN) fcntl.flock(fileno, fcntl.LOCK_EX) fcntl.flock(fileno, fcntl.LOCK_UN) self.assertRaises(ValueError, fcntl.flock, -1, fcntl.LOCK_SH) self.assertRaises(TypeError, fcntl.flock, 'spam', fcntl.LOCK_SH) @unittest.skipIf(platform.system() == "AIX", "AIX returns PermissionError") def test_lockf_exclusive(self): self.f = open(TESTFN, 'wb+') cmd = fcntl.LOCK_EX | fcntl.LOCK_NB fcntl.lockf(self.f, cmd) mp = multiprocessing.get_context('spawn') p = mp.Process(target=try_lockf_on_other_process_fail, args=(TESTFN, cmd)) p.start() p.join() fcntl.lockf(self.f, fcntl.LOCK_UN) self.assertEqual(p.exitcode, 0) @unittest.skipIf(platform.system() == "AIX", "AIX returns PermissionError") def test_lockf_share(self): self.f = open(TESTFN, 'wb+') cmd = fcntl.LOCK_SH | fcntl.LOCK_NB fcntl.lockf(self.f, cmd) mp = multiprocessing.get_context('spawn') p = mp.Process(target=try_lockf_on_other_process, args=(TESTFN, cmd)) p.start() p.join() fcntl.lockf(self.f, fcntl.LOCK_UN) self.assertEqual(p.exitcode, 0) @cpython_only def test_flock_overflow(self): import _testcapi self.assertRaises(OverflowError, fcntl.flock, _testcapi.INT_MAX+1, fcntl.LOCK_SH) @unittest.skipIf(sys.platform != 'darwin', "F_GETPATH is only available on macos") def test_fcntl_f_getpath(self): self.f = open(TESTFN, 'wb') expected = os.path.abspath(TESTFN).encode('utf-8') res = fcntl.fcntl(self.f.fileno(), fcntl.F_GETPATH, bytes(len(expected))) self.assertEqual(expected, res) @unittest.skipUnless( hasattr(fcntl, "F_SETPIPE_SZ") and hasattr(fcntl, "F_GETPIPE_SZ"), "F_SETPIPE_SZ and F_GETPIPE_SZ are not available on all platforms.") def test_fcntl_f_pipesize(self): test_pipe_r, test_pipe_w = os.pipe() try: # Get the default pipesize with F_GETPIPE_SZ pipesize_default = fcntl.fcntl(test_pipe_w, fcntl.F_GETPIPE_SZ) pipesize = pipesize_default // 2 # A new value to detect change. pagesize_default = get_pagesize() if pipesize < pagesize_default: # the POSIX minimum raise unittest.SkipTest( 'default pipesize too small to perform test.') fcntl.fcntl(test_pipe_w, fcntl.F_SETPIPE_SZ, pipesize) self.assertEqual(fcntl.fcntl(test_pipe_w, fcntl.F_GETPIPE_SZ), pipesize) finally: os.close(test_pipe_r) os.close(test_pipe_w) if __name__ == '__main__': unittest.main()