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#!/usr/bin/env python

# Copyright (c) 2009, Giampaolo Rodola'. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""Linux specific tests.  These are implicitly run by test_psutil.py."""

from __future__ import division

import contextlib
import errno
import fcntl
import io
import os
import pprint
import re
import shutil
import socket
import struct
import sys
import tempfile
import time
import warnings

try:
    from unittest import mock  # py3
except ImportError:
    import mock  # requires "pip install mock"

import psutil
import psutil._pslinux
from psutil._compat import PY3
from psutil._compat import u
from test_psutil import call_until
from test_psutil import get_kernel_version
from test_psutil import get_test_subprocess
from test_psutil import importlib
from test_psutil import LINUX
from test_psutil import MEMORY_TOLERANCE
from test_psutil import POSIX
from test_psutil import retry_before_failing
from test_psutil import sh
from test_psutil import skip_on_not_implemented
from test_psutil import TRAVIS
from test_psutil import unittest
from test_psutil import which

HERE = os.path.abspath(os.path.dirname(__file__))
# procps-ng 3.3.10 changed the output format of free
# and removed the 'buffers/cache line'
OLD_PROCPS_NG_VERSION = 'buffers/cache' in sh('free')

SIOCGIFADDR = 0x8915
SIOCGIFCONF = 0x8912
SIOCGIFHWADDR = 0x8927


def get_ipv4_address(ifname):
    ifname = ifname[:15]
    if PY3:
        ifname = bytes(ifname, 'ascii')
    s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    with contextlib.closing(s):
        return socket.inet_ntoa(
            fcntl.ioctl(s.fileno(),
                        SIOCGIFADDR,
                        struct.pack('256s', ifname))[20:24])


def get_mac_address(ifname):
    ifname = ifname[:15]
    if PY3:
        ifname = bytes(ifname, 'ascii')
    s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    with contextlib.closing(s):
        info = fcntl.ioctl(
            s.fileno(), SIOCGIFHWADDR, struct.pack('256s', ifname))
        if PY3:
            def ord(x):
                return x
        else:
            import __builtin__
            ord = __builtin__.ord
        return ''.join(['%02x:' % ord(char) for char in info[18:24]])[:-1]


@unittest.skipUnless(LINUX, "not a Linux system")
class LinuxSpecificTestCase(unittest.TestCase):

    @unittest.skipIf(
        POSIX and not hasattr(os, 'statvfs'),
        reason="os.statvfs() function not available on this platform")
    @skip_on_not_implemented()
    def test_disks(self):
        # test psutil.disk_usage() and psutil.disk_partitions()
        # against "df -a"
        def df(path):
            out = sh('df -P -B 1 "%s"' % path).strip()
            lines = out.split('\n')
            lines.pop(0)
            line = lines.pop(0)
            dev, total, used, free = line.split()[:4]
            if dev == 'none':
                dev = ''
            total, used, free = int(total), int(used), int(free)
            return dev, total, used, free

        for part in psutil.disk_partitions(all=False):
            usage = psutil.disk_usage(part.mountpoint)
            dev, total, used, free = df(part.mountpoint)
            self.assertEqual(part.device, dev)
            self.assertEqual(usage.total, total)
            # 10 MB tollerance
            if abs(usage.free - free) > 10 * 1024 * 1024:
                self.fail("psutil=%s, df=%s" % (usage.free, free))
            if abs(usage.used - used) > 10 * 1024 * 1024:
                self.fail("psutil=%s, df=%s" % (usage.used, used))

    def test_memory_maps(self):
        sproc = get_test_subprocess()
        time.sleep(1)
        p = psutil.Process(sproc.pid)
        maps = p.memory_maps(grouped=False)
        pmap = sh('pmap -x %s' % p.pid).split('\n')
        # get rid of header
        del pmap[0]
        del pmap[0]
        while maps and pmap:
            this = maps.pop(0)
            other = pmap.pop(0)
            addr, _, rss, dirty, mode, path = other.split(None, 5)
            if not path.startswith('[') and not path.endswith(']'):
                self.assertEqual(path, os.path.basename(this.path))
            self.assertEqual(int(rss) * 1024, this.rss)
            # test only rwx chars, ignore 's' and 'p'
            self.assertEqual(mode[:3], this.perms[:3])

    def test_vmem_total(self):
        lines = sh('free').split('\n')[1:]
        total = int(lines[0].split()[1]) * 1024
        self.assertEqual(total, psutil.virtual_memory().total)

    @retry_before_failing()
    def test_vmem_used(self):
        lines = sh('free').split('\n')[1:]
        total = int(lines[0].split()[1])
        free = int(lines[0].split()[3])
        used = (total - free) * 1024
        self.assertAlmostEqual(used, psutil.virtual_memory().used,
                               delta=MEMORY_TOLERANCE)

    @retry_before_failing()
    def test_vmem_free(self):
        lines = sh('free').split('\n')[1:]
        free = int(lines[0].split()[3]) * 1024
        self.assertAlmostEqual(free, psutil.virtual_memory().free,
                               delta=MEMORY_TOLERANCE)

    @retry_before_failing()
    def test_vmem_buffers(self):
        buffers = int(sh('vmstat').split('\n')[2].split()[4]) * 1024
        self.assertAlmostEqual(buffers, psutil.virtual_memory().buffers,
                               delta=MEMORY_TOLERANCE)

    @retry_before_failing()
    def test_vmem_cached(self):
        cached = int(sh('vmstat').split('\n')[2].split()[5]) * 1024
        self.assertAlmostEqual(cached, psutil.virtual_memory().cached,
                               delta=MEMORY_TOLERANCE)

    def test_swapmem_total(self):
        lines = sh('free').split('\n')[1:]
        total = int(lines[2 if OLD_PROCPS_NG_VERSION else 1].split()[1]) * 1024
        self.assertEqual(total, psutil.swap_memory().total)

    @retry_before_failing()
    def test_swapmem_used(self):
        lines = sh('free').split('\n')[1:]
        used = int(lines[2 if OLD_PROCPS_NG_VERSION else 1].split()[2]) * 1024
        self.assertAlmostEqual(used, psutil.swap_memory().used,
                               delta=MEMORY_TOLERANCE)

    @retry_before_failing()
    def test_swapmem_free(self):
        lines = sh('free').split('\n')[1:]
        free = int(lines[2 if OLD_PROCPS_NG_VERSION else 1].split()[1]) * 1024
        self.assertAlmostEqual(free, psutil.swap_memory().free,
                               delta=MEMORY_TOLERANCE)

    @unittest.skipIf(TRAVIS, "unknown failure on travis")
    def test_cpu_times(self):
        fields = psutil.cpu_times()._fields
        kernel_ver = re.findall('\d+\.\d+\.\d+', os.uname()[2])[0]
        kernel_ver_info = tuple(map(int, kernel_ver.split('.')))
        if kernel_ver_info >= (2, 6, 11):
            self.assertIn('steal', fields)
        else:
            self.assertNotIn('steal', fields)
        if kernel_ver_info >= (2, 6, 24):
            self.assertIn('guest', fields)
        else:
            self.assertNotIn('guest', fields)
        if kernel_ver_info >= (3, 2, 0):
            self.assertIn('guest_nice', fields)
        else:
            self.assertNotIn('guest_nice', fields)

    def test_net_if_addrs_ips(self):
        for name, addrs in psutil.net_if_addrs().items():
            for addr in addrs:
                if addr.family == psutil.AF_LINK:
                    self.assertEqual(addr.address, get_mac_address(name))
                elif addr.family == socket.AF_INET:
                    self.assertEqual(addr.address, get_ipv4_address(name))
                # TODO: test for AF_INET6 family

    @unittest.skipUnless(which('ip'), "'ip' utility not available")
    @unittest.skipIf(TRAVIS, "skipped on Travis")
    def test_net_if_names(self):
        out = sh("ip addr").strip()
        nics = [x for x in psutil.net_if_addrs().keys() if ':' not in x]
        found = 0
        for line in out.split('\n'):
            line = line.strip()
            if re.search("^\d+:", line):
                found += 1
                name = line.split(':')[1].strip()
                self.assertIn(name, nics)
        self.assertEqual(len(nics), found, msg="%s\n---\n%s" % (
            pprint.pformat(nics), out))

    @unittest.skipUnless(which("nproc"), "nproc utility not available")
    def test_cpu_count_logical_w_nproc(self):
        num = int(sh("nproc --all"))
        self.assertEqual(psutil.cpu_count(logical=True), num)

    @unittest.skipUnless(which("lscpu"), "lscpu utility not available")
    def test_cpu_count_logical_w_lscpu(self):
        out = sh("lscpu -p")
        num = len([x for x in out.split('\n') if not x.startswith('#')])
        self.assertEqual(psutil.cpu_count(logical=True), num)

    # --- mocked tests

    def test_virtual_memory_mocked_warnings(self):
        with mock.patch('psutil._pslinux.open', create=True) as m:
            with warnings.catch_warnings(record=True) as ws:
                warnings.simplefilter("always")
                ret = psutil._pslinux.virtual_memory()
                assert m.called
                self.assertEqual(len(ws), 1)
                w = ws[0]
                self.assertTrue(w.filename.endswith('psutil/_pslinux.py'))
                self.assertIn(
                    "'cached', 'active' and 'inactive' memory stats couldn't "
                    "be determined", str(w.message))
                self.assertEqual(ret.cached, 0)
                self.assertEqual(ret.active, 0)
                self.assertEqual(ret.inactive, 0)

    def test_swap_memory_mocked_warnings(self):
        with mock.patch('psutil._pslinux.open', create=True) as m:
            with warnings.catch_warnings(record=True) as ws:
                warnings.simplefilter("always")
                ret = psutil._pslinux.swap_memory()
                assert m.called
                self.assertEqual(len(ws), 1)
                w = ws[0]
                self.assertTrue(w.filename.endswith('psutil/_pslinux.py'))
                self.assertIn(
                    "'sin' and 'sout' swap memory stats couldn't "
                    "be determined", str(w.message))
                self.assertEqual(ret.sin, 0)
                self.assertEqual(ret.sout, 0)

    def test_swap_memory_mocked_no_vmstat(self):
        # see https://github.com/giampaolo/psutil/issues/722
        with mock.patch('psutil._pslinux.open', create=True,
                        side_effect=IOError) as m:
            with warnings.catch_warnings(record=True) as ws:
                warnings.simplefilter("always")
                ret = psutil.swap_memory()
                assert m.called
                self.assertEqual(len(ws), 1)
                w = ws[0]
                self.assertTrue(w.filename.endswith('psutil/_pslinux.py'))
                self.assertIn(
                    "'sin' and 'sout' swap memory stats couldn't "
                    "be determined and were set to 0",
                    str(w.message))
                self.assertEqual(ret.sin, 0)
                self.assertEqual(ret.sout, 0)

    def test_cpu_count_logical_mocked(self):
        import psutil._pslinux
        original = psutil._pslinux.cpu_count_logical()
        # Here we want to mock os.sysconf("SC_NPROCESSORS_ONLN") in
        # order to cause the parsing of /proc/cpuinfo and /proc/stat.
        with mock.patch(
                'psutil._pslinux.os.sysconf', side_effect=ValueError) as m:
            self.assertEqual(psutil._pslinux.cpu_count_logical(), original)
            assert m.called

            # Let's have open() return emtpy data and make sure None is
            # returned ('cause we mimick os.cpu_count()).
            with mock.patch('psutil._pslinux.open', create=True) as m:
                self.assertIsNone(psutil._pslinux.cpu_count_logical())
                self.assertEqual(m.call_count, 2)
                # /proc/stat should be the last one
                self.assertEqual(m.call_args[0][0], '/proc/stat')

            # Let's push this a bit further and make sure /proc/cpuinfo
            # parsing works as expected.
            with open('/proc/cpuinfo', 'rb') as f:
                cpuinfo_data = f.read()
            fake_file = io.BytesIO(cpuinfo_data)
            with mock.patch('psutil._pslinux.open',
                            return_value=fake_file, create=True) as m:
                self.assertEqual(psutil._pslinux.cpu_count_logical(), original)

    def test_cpu_count_physical_mocked(self):
        # Have open() return emtpy data and make sure None is returned
        # ('cause we want to mimick os.cpu_count())
        with mock.patch('psutil._pslinux.open', create=True) as m:
            self.assertIsNone(psutil._pslinux.cpu_count_physical())
            assert m.called

    def test_proc_open_files_file_gone(self):
        # simulates a file which gets deleted during open_files()
        # execution
        p = psutil.Process()
        files = p.open_files()
        with tempfile.NamedTemporaryFile():
            # give the kernel some time to see the new file
            call_until(p.open_files, "len(ret) != %i" % len(files))
            with mock.patch('psutil._pslinux.os.readlink',
                            side_effect=OSError(errno.ENOENT, "")) as m:
                files = p.open_files()
                assert not files
                assert m.called
            # also simulate the case where os.readlink() returns EINVAL
            # in which case psutil is supposed to 'continue'
            with mock.patch('psutil._pslinux.os.readlink',
                            side_effect=OSError(errno.EINVAL, "")) as m:
                self.assertEqual(p.open_files(), [])
                assert m.called

    def test_proc_terminal_mocked(self):
        with mock.patch('psutil._pslinux._psposix._get_terminal_map',
                        return_value={}) as m:
            self.assertIsNone(psutil._pslinux.Process(os.getpid()).terminal())
            assert m.called

    def test_proc_num_ctx_switches_mocked(self):
        with mock.patch('psutil._pslinux.open', create=True) as m:
            self.assertRaises(
                NotImplementedError,
                psutil._pslinux.Process(os.getpid()).num_ctx_switches)
            assert m.called

    def test_proc_num_threads_mocked(self):
        with mock.patch('psutil._pslinux.open', create=True) as m:
            self.assertRaises(
                NotImplementedError,
                psutil._pslinux.Process(os.getpid()).num_threads)
            assert m.called

    def test_proc_ppid_mocked(self):
        with mock.patch('psutil._pslinux.open', create=True) as m:
            self.assertRaises(
                NotImplementedError,
                psutil._pslinux.Process(os.getpid()).ppid)
            assert m.called

    def test_proc_uids_mocked(self):
        with mock.patch('psutil._pslinux.open', create=True) as m:
            self.assertRaises(
                NotImplementedError,
                psutil._pslinux.Process(os.getpid()).uids)
            assert m.called

    def test_proc_gids_mocked(self):
        with mock.patch('psutil._pslinux.open', create=True) as m:
            self.assertRaises(
                NotImplementedError,
                psutil._pslinux.Process(os.getpid()).gids)
            assert m.called

    def test_proc_cmdline_mocked(self):
        # see: https://github.com/giampaolo/psutil/issues/639
        p = psutil.Process()
        fake_file = io.StringIO(u('foo\x00bar\x00'))
        with mock.patch('psutil._pslinux.open',
                        return_value=fake_file, create=True) as m:
            p.cmdline() == ['foo', 'bar']
            assert m.called
        fake_file = io.StringIO(u('foo\x00bar\x00\x00'))
        with mock.patch('psutil._pslinux.open',
                        return_value=fake_file, create=True) as m:
            p.cmdline() == ['foo', 'bar', '']
            assert m.called

    def test_proc_io_counters_mocked(self):
        with mock.patch('psutil._pslinux.open', create=True) as m:
            self.assertRaises(
                NotImplementedError,
                psutil._pslinux.Process(os.getpid()).io_counters)
            assert m.called

    def test_boot_time_mocked(self):
        with mock.patch('psutil._pslinux.open', create=True) as m:
            self.assertRaises(
                RuntimeError,
                psutil._pslinux.boot_time)
            assert m.called

    def test_users_mocked(self):
        # Make sure ':0' and ':0.0' (returned by C ext) are converted
        # to 'localhost'.
        with mock.patch('psutil._pslinux.cext.users',
                        return_value=[('giampaolo', 'pts/2', ':0',
                                      1436573184.0, True)]) as m:
            self.assertEqual(psutil.users()[0].host, 'localhost')
            assert m.called
        with mock.patch('psutil._pslinux.cext.users',
                        return_value=[('giampaolo', 'pts/2', ':0.0',
                                      1436573184.0, True)]) as m:
            self.assertEqual(psutil.users()[0].host, 'localhost')
            assert m.called
        # ...otherwise it should be returned as-is
        with mock.patch('psutil._pslinux.cext.users',
                        return_value=[('giampaolo', 'pts/2', 'foo',
                                      1436573184.0, True)]) as m:
            self.assertEqual(psutil.users()[0].host, 'foo')
            assert m.called

    def test_disk_partitions_mocked(self):
        # Test that ZFS partitions are returned.
        with open("/proc/filesystems", "r") as f:
            data = f.read()
        if 'zfs' in data:
            for part in psutil.disk_partitions():
                if part.fstype == 'zfs':
                    break
            else:
                self.fail("couldn't find any ZFS partition")
        else:
            # No ZFS partitions on this system. Let's fake one.
            fake_file = io.StringIO(u("nodev\tzfs\n"))
            with mock.patch('psutil._pslinux.open',
                            return_value=fake_file, create=True) as m1:
                with mock.patch(
                        'psutil._pslinux.cext.disk_partitions',
                        return_value=[('/dev/sdb3', '/', 'zfs', 'rw')]) as m2:
                    ret = psutil.disk_partitions()
                    assert m1.called
                    assert m2.called
                    assert ret
                    self.assertEqual(ret[0].fstype, 'zfs')

    @mock.patch('psutil._pslinux.socket.inet_ntop', side_effect=ValueError)
    @mock.patch('psutil._pslinux.supports_ipv6', return_value=False)
    def test_connections_ipv6_not_supported(self, supports_ipv6, inet_ntop):
        # see: https://github.com/giampaolo/psutil/issues/623
        try:
            s = socket.socket(socket.AF_INET6, socket.SOCK_STREAM)
            self.addCleanup(s.close)
            s.bind(("::1", 0))
        except socket.error:
            pass
        psutil.net_connections(kind='inet6')

    def test_procfs_path(self):
        tdir = tempfile.mkdtemp()
        try:
            psutil.PROCFS_PATH = tdir
            self.assertRaises(IOError, psutil.virtual_memory)
            self.assertRaises(IOError, psutil.cpu_times)
            self.assertRaises(IOError, psutil.cpu_times, percpu=True)
            self.assertRaises(IOError, psutil.boot_time)
            # self.assertRaises(IOError, psutil.pids)
            self.assertRaises(IOError, psutil.net_connections)
            self.assertRaises(IOError, psutil.net_io_counters)
            self.assertRaises(IOError, psutil.net_if_stats)
            self.assertRaises(IOError, psutil.disk_io_counters)
            self.assertRaises(IOError, psutil.disk_partitions)
            self.assertRaises(psutil.NoSuchProcess, psutil.Process)
        finally:
            psutil.PROCFS_PATH = "/proc"
            os.rmdir(tdir)

    @mock.patch('psutil.traceback.print_exc')
    def test_no_procfs_for_import(self, tb):
        my_procfs = tempfile.mkdtemp()

        with open(os.path.join(my_procfs, 'stat'), 'w') as f:
            f.write('cpu   0 0 0 0 0 0 0 0 0 0\n')
            f.write('cpu0  0 0 0 0 0 0 0 0 0 0\n')
            f.write('cpu1  0 0 0 0 0 0 0 0 0 0\n')

        try:
            orig_open = open

            def open_mock(name, *args):
                if name.startswith('/proc'):
                    raise IOError(errno.ENOENT, 'rejecting access for test')
                return orig_open(name, *args)

            patch_point = 'builtins.open' if PY3 else '__builtin__.open'
            with mock.patch(patch_point, side_effect=open_mock):
                importlib.reload(psutil)
                assert tb.called

                self.assertRaises(IOError, psutil.cpu_times)
                self.assertRaises(IOError, psutil.cpu_times, percpu=True)
                self.assertRaises(IOError, psutil.cpu_percent)
                self.assertRaises(IOError, psutil.cpu_percent, percpu=True)
                self.assertRaises(IOError, psutil.cpu_times_percent)
                self.assertRaises(
                    IOError, psutil.cpu_times_percent, percpu=True)

                psutil.PROCFS_PATH = my_procfs

                self.assertEqual(psutil.cpu_percent(), 0)
                self.assertEqual(sum(psutil.cpu_times_percent()), 0)

                # since we don't know the number of CPUs at import time,
                # we awkwardly say there are none until the second call
                per_cpu_percent = psutil.cpu_percent(percpu=True)
                self.assertEqual(sum(per_cpu_percent), 0)

                # ditto awkward length
                per_cpu_times_percent = psutil.cpu_times_percent(percpu=True)
                self.assertEqual(sum(map(sum, per_cpu_times_percent)), 0)

                # much user, very busy
                with open(os.path.join(my_procfs, 'stat'), 'w') as f:
                    f.write('cpu   1 0 0 0 0 0 0 0 0 0\n')
                    f.write('cpu0  1 0 0 0 0 0 0 0 0 0\n')
                    f.write('cpu1  1 0 0 0 0 0 0 0 0 0\n')

                self.assertNotEqual(psutil.cpu_percent(), 0)
                self.assertNotEqual(
                    sum(psutil.cpu_percent(percpu=True)), 0)
                self.assertNotEqual(sum(psutil.cpu_times_percent()), 0)
                self.assertNotEqual(
                    sum(map(sum, psutil.cpu_times_percent(percpu=True))), 0)
        finally:
            shutil.rmtree(my_procfs)
            importlib.reload(psutil)

        self.assertEqual(psutil.PROCFS_PATH, '/proc')

    @unittest.skipUnless(
        get_kernel_version() >= (2, 6, 36),
        "prlimit() not available on this Linux kernel version")
    def test_prlimit_availability(self):
        # prlimit() should be available starting from kernel 2.6.36
        p = psutil.Process(os.getpid())
        p.rlimit(psutil.RLIMIT_NOFILE)
        # if prlimit() is supported *at least* these constants should
        # be available
        self.assertTrue(hasattr(psutil, "RLIM_INFINITY"))
        self.assertTrue(hasattr(psutil, "RLIMIT_AS"))
        self.assertTrue(hasattr(psutil, "RLIMIT_CORE"))
        self.assertTrue(hasattr(psutil, "RLIMIT_CPU"))
        self.assertTrue(hasattr(psutil, "RLIMIT_DATA"))
        self.assertTrue(hasattr(psutil, "RLIMIT_FSIZE"))
        self.assertTrue(hasattr(psutil, "RLIMIT_LOCKS"))
        self.assertTrue(hasattr(psutil, "RLIMIT_MEMLOCK"))
        self.assertTrue(hasattr(psutil, "RLIMIT_NOFILE"))
        self.assertTrue(hasattr(psutil, "RLIMIT_NPROC"))
        self.assertTrue(hasattr(psutil, "RLIMIT_RSS"))
        self.assertTrue(hasattr(psutil, "RLIMIT_STACK"))

    @unittest.skipUnless(
        get_kernel_version() >= (3, 0),
        "prlimit constants not available on this Linux kernel version")
    def test_resource_consts_kernel_v(self):
        # more recent constants
        self.assertTrue(hasattr(psutil, "RLIMIT_MSGQUEUE"))
        self.assertTrue(hasattr(psutil, "RLIMIT_NICE"))
        self.assertTrue(hasattr(psutil, "RLIMIT_RTPRIO"))
        self.assertTrue(hasattr(psutil, "RLIMIT_RTTIME"))
        self.assertTrue(hasattr(psutil, "RLIMIT_SIGPENDING"))

    def test_path_deleted(self):
        with mock.patch('psutil._pslinux.os.readlink',
                        return_value='/home/foo (deleted)'):
            self.assertEqual(psutil.Process().exe(), "/home/foo")
            self.assertEqual(psutil.Process().cwd(), "/home/foo")


def main():
    test_suite = unittest.TestSuite()
    test_suite.addTest(unittest.makeSuite(LinuxSpecificTestCase))
    result = unittest.TextTestRunner(verbosity=2).run(test_suite)
    return result.wasSuccessful()

if __name__ == '__main__':
    if not main():
        sys.exit(1)