"""Test program for the fcntl C module.
"""
import multiprocessing
import platform
import os
import struct
import sys
import unittest
from test.support import (
cpython_only, get_pagesize, is_apple, requires_subprocess, verbose
)
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 is_apple
):
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):
_testcapi = import_module("_testcapi")
INT_MAX = _testcapi.INT_MAX
INT_MIN = _testcapi.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")
or platform.system() == "Android",
"this platform 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")
@requires_subprocess()
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")
@requires_subprocess()
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):
_testcapi = import_module("_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()
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