summaryrefslogtreecommitdiffstats
path: root/Lib/test/test_resource.py
blob: 317e7ca8f8c8537c399fcd197bf972e068beffe1 (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
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
import contextlib
import sys
import unittest
from test import support
from test.support import import_helper
from test.support import os_helper
import time

resource = import_helper.import_module('resource')

# This test is checking a few specific problem spots with the resource module.

class ResourceTest(unittest.TestCase):

    def test_args(self):
        self.assertRaises(TypeError, resource.getrlimit)
        self.assertRaises(TypeError, resource.getrlimit, 42, 42)
        self.assertRaises(TypeError, resource.setrlimit)
        self.assertRaises(TypeError, resource.setrlimit, 42, 42, 42)

    @unittest.skipIf(sys.platform == "vxworks",
                     "setting RLIMIT_FSIZE is not supported on VxWorks")
    def test_fsize_ismax(self):
        try:
            (cur, max) = resource.getrlimit(resource.RLIMIT_FSIZE)
        except AttributeError:
            pass
        else:
            # RLIMIT_FSIZE should be RLIM_INFINITY, which will be a really big
            # number on a platform with large file support.  On these platforms,
            # we need to test that the get/setrlimit functions properly convert
            # the number to a C long long and that the conversion doesn't raise
            # an error.
            self.assertEqual(resource.RLIM_INFINITY, max)
            resource.setrlimit(resource.RLIMIT_FSIZE, (cur, max))

    def test_fsize_enforced(self):
        try:
            (cur, max) = resource.getrlimit(resource.RLIMIT_FSIZE)
        except AttributeError:
            pass
        else:
            # Check to see what happens when the RLIMIT_FSIZE is small.  Some
            # versions of Python were terminated by an uncaught SIGXFSZ, but
            # pythonrun.c has been fixed to ignore that exception.  If so, the
            # write() should return EFBIG when the limit is exceeded.

            # At least one platform has an unlimited RLIMIT_FSIZE and attempts
            # to change it raise ValueError instead.
            try:
                try:
                    resource.setrlimit(resource.RLIMIT_FSIZE, (1024, max))
                    limit_set = True
                except ValueError:
                    limit_set = False
                f = open(os_helper.TESTFN, "wb")
                try:
                    f.write(b"X" * 1024)
                    try:
                        f.write(b"Y")
                        f.flush()
                        # On some systems (e.g., Ubuntu on hppa) the flush()
                        # doesn't always cause the exception, but the close()
                        # does eventually.  Try flushing several times in
                        # an attempt to ensure the file is really synced and
                        # the exception raised.
                        for i in range(5):
                            time.sleep(.1)
                            f.flush()
                    except OSError:
                        if not limit_set:
                            raise
                    if limit_set:
                        # Close will attempt to flush the byte we wrote
                        # Restore limit first to avoid getting a spurious error
                        resource.setrlimit(resource.RLIMIT_FSIZE, (cur, max))
                finally:
                    f.close()
            finally:
                if limit_set:
                    resource.setrlimit(resource.RLIMIT_FSIZE, (cur, max))
                os_helper.unlink(os_helper.TESTFN)

    def test_fsize_toobig(self):
        # Be sure that setrlimit is checking for really large values
        too_big = 10**50
        try:
            (cur, max) = resource.getrlimit(resource.RLIMIT_FSIZE)
        except AttributeError:
            pass
        else:
            try:
                resource.setrlimit(resource.RLIMIT_FSIZE, (too_big, max))
            except (OverflowError, ValueError):
                pass
            try:
                resource.setrlimit(resource.RLIMIT_FSIZE, (max, too_big))
            except (OverflowError, ValueError):
                pass

    @unittest.skipUnless(hasattr(resource, "getrusage"), "needs getrusage")
    def test_getrusage(self):
        self.assertRaises(TypeError, resource.getrusage)
        self.assertRaises(TypeError, resource.getrusage, 42, 42)
        usageself = resource.getrusage(resource.RUSAGE_SELF)
        usagechildren = resource.getrusage(resource.RUSAGE_CHILDREN)
        # May not be available on all systems.
        try:
            usageboth = resource.getrusage(resource.RUSAGE_BOTH)
        except (ValueError, AttributeError):
            pass
        try:
            usage_thread = resource.getrusage(resource.RUSAGE_THREAD)
        except (ValueError, AttributeError):
            pass

    # Issue 6083: Reference counting bug
    @unittest.skipIf(sys.platform == "vxworks",
                     "setting RLIMIT_CPU is not supported on VxWorks")
    def test_setrusage_refcount(self):
        try:
            limits = resource.getrlimit(resource.RLIMIT_CPU)
        except AttributeError:
            pass
        else:
            class BadSequence:
                def __len__(self):
                    return 2
                def __getitem__(self, key):
                    if key in (0, 1):
                        return len(tuple(range(1000000)))
                    raise IndexError

            resource.setrlimit(resource.RLIMIT_CPU, BadSequence())

    def test_pagesize(self):
        pagesize = resource.getpagesize()
        self.assertIsInstance(pagesize, int)
        self.assertGreaterEqual(pagesize, 0)

    @unittest.skipUnless(sys.platform == 'linux', 'test requires Linux')
    def test_linux_constants(self):
        for attr in ['MSGQUEUE', 'NICE', 'RTPRIO', 'RTTIME', 'SIGPENDING']:
            with contextlib.suppress(AttributeError):
                self.assertIsInstance(getattr(resource, 'RLIMIT_' + attr), int)

    def test_freebsd_contants(self):
        for attr in ['SWAP', 'SBSIZE', 'NPTS']:
            with contextlib.suppress(AttributeError):
                self.assertIsInstance(getattr(resource, 'RLIMIT_' + attr), int)

    @unittest.skipUnless(hasattr(resource, 'prlimit'), 'no prlimit')
    @support.requires_linux_version(2, 6, 36)
    def test_prlimit(self):
        self.assertRaises(TypeError, resource.prlimit)
        self.assertRaises(ProcessLookupError, resource.prlimit,
                          -1, resource.RLIMIT_AS)
        limit = resource.getrlimit(resource.RLIMIT_AS)
        self.assertEqual(resource.prlimit(0, resource.RLIMIT_AS), limit)
        self.assertEqual(resource.prlimit(0, resource.RLIMIT_AS, limit),
                         limit)

    # Issue 20191: Reference counting bug
    @unittest.skipUnless(hasattr(resource, 'prlimit'), 'no prlimit')
    @support.requires_linux_version(2, 6, 36)
    def test_prlimit_refcount(self):
        class BadSeq:
            def __len__(self):
                return 2
            def __getitem__(self, key):
                return limits[key] - 1  # new reference

        limits = resource.getrlimit(resource.RLIMIT_AS)
        self.assertEqual(resource.prlimit(0, resource.RLIMIT_AS, BadSeq()),
                         limits)


if __name__ == "__main__":
    unittest.main()