summaryrefslogtreecommitdiffstats
path: root/Lib/test/test_fcntl.py
blob: e2a1b374cddc44e66bba227ecff3665ebf72ef39 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
"""Test program for the fcntl C module.

OS/2+EMX doesn't support the file locking operations.

"""
import platform
import os
import struct
import sys
import _testcapi
import unittest
from test.support import verbose, TESTFN, unlink, run_unittest, import_module

# Skip test if no fnctl module.
fcntl = import_module('fcntl')


# TODO - Write tests for flock() and lockf().

def get_lockdata():
    try:
        os.O_LARGEFILE
    except AttributeError:
        start_len = "ll"
    else:
        start_len = "qq"

    if (sys.platform.startswith(('netbsd', 'freebsd', 'openbsd', 'bsdos'))
        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 ['aix3', 'aix4', 'hp-uxB', 'unixware7']:
        lockdata = struct.pack('hhlllii', fcntl.F_WRLCK, 0, 0, 0, 0, 0, 0)
    elif sys.platform in ['os2emx']:
        lockdata = None
    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

lockdata = get_lockdata()

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)

    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)
        if sys.platform not in ['os2emx']:
            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 sys.platform not in ['os2emx']:
            rv = fcntl.fcntl(self.f, fcntl.F_SETLKW, lockdata)
        self.f.close()

    def test_fcntl_bad_file(self):
        class F:
            def __init__(self, fn):
                self.fn = fn
            def fileno(self):
                return self.fn
        self.assertRaises(ValueError, fcntl.fcntl, -1, fcntl.F_SETFL, os.O_NONBLOCK)
        self.assertRaises(ValueError, fcntl.fcntl, F(-1), fcntl.F_SETFL, os.O_NONBLOCK)
        self.assertRaises(TypeError, fcntl.fcntl, 'spam', fcntl.F_SETFL, os.O_NONBLOCK)
        self.assertRaises(TypeError, fcntl.fcntl, F('spam'), fcntl.F_SETFL, os.O_NONBLOCK)
        # Issue 15989
        self.assertRaises(OverflowError, fcntl.fcntl, _testcapi.INT_MAX + 1,
                                                      fcntl.F_SETFL, os.O_NONBLOCK)
        self.assertRaises(OverflowError, fcntl.fcntl, F(_testcapi.INT_MAX + 1),
                                                      fcntl.F_SETFL, os.O_NONBLOCK)
        self.assertRaises(OverflowError, fcntl.fcntl, _testcapi.INT_MIN - 1,
                                                      fcntl.F_SETFL, os.O_NONBLOCK)
        self.assertRaises(OverflowError, fcntl.fcntl, F(_testcapi.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_main():
    run_unittest(TestFcntl)

if __name__ == '__main__':
    test_main()