# -*- coding: utf-8 -*-

# Copyright (C) 2012-2018 Red Hat, Inc.

#

# This copyrighted material is made available to anyone wishing to use,

# modify, copy, or redistribute it subject to the terms and conditions of

# the GNU General Public License v.2, or (at your option) any later version.

# This program is distributed in the hope that it will be useful, but WITHOUT

# ANY WARRANTY expressed or implied, including the implied warranties of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General

# Public License for more details.  You should have received a copy of the

# GNU General Public License along with this program; if not, write to the

# Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA

# 02110-1301, USA.  Any Red Hat trademarks that are incorporated in the

# source code or documentation are not subject to the GNU General Public

# License and may only be used or replicated with the express permission of

# Red Hat, Inc.

#

"""Unit test dnf.lock module.

Locking is very hard to cover reasonably with a unit test, this is more or less

just a sanity check.

"""

from __future__ import absolute_import

from __future__ import unicode_literals

import multiprocessing

import os

import re

import threading

import dnf.lock

import dnf.pycomp

import dnf.util

from dnf.exceptions import ProcessLockError, ThreadLockError

import tests.support

from tests.support import mock

class ConcurrencyMixin(object):

    def __init__(self, lock):

        self.lock = lock

    def run(self):

        try:

            with self.lock:

                pass

        except (ProcessLockError, ThreadLockError) as e:

            self.queue.put(e)

class OtherThread(ConcurrencyMixin, threading.Thread):

    def __init__(self, lock):

        ConcurrencyMixin.__init__(self, lock)

        threading.Thread.__init__(self)

        self.queue = dnf.pycomp.Queue(1)

class OtherProcess(ConcurrencyMixin, multiprocessing.Process):

    def __init__(self, lock):

        ConcurrencyMixin.__init__(self, lock)

        multiprocessing.Process.__init__(self)

        self.queue = multiprocessing.Queue(1)

TARGET = os.path.join(tests.support.USER_RUNDIR, 'unit-test.pid')

def build_lock(blocking=False):

    return dnf.lock.ProcessLock(TARGET, 'unit-tests', blocking)

class LockTest(tests.support.TestCase):

    def test_fit_lock_dir(self):

        orig = '/some'

        with mock.patch('dnf.util.am_i_root', return_value=True):

            self.assertEqual(dnf.lock._fit_lock_dir(orig), '/some')

        with mock.patch('dnf.util.am_i_root', return_value=False):

            dir_ = dnf.lock._fit_lock_dir(orig)

            match = re.match(

                r'/var/tmp/dnf-[^:]+-[^/]+/locks/2690814ff0269c86e5109d2915ea572092918cb3',

                dir_)

            self.assertTrue(match)

class ProcessLockTest(tests.support.TestCase):

    @classmethod

    def tearDownClass(cls):

        dnf.util.rm_rf(tests.support.USER_RUNDIR)

    def test_simple(self):

        l1 = build_lock()

        target = l1.target

        with l1:

            self.assertFile(target)

        self.assertPathDoesNotExist(target)

    def test_reentrance(self):

        l1 = build_lock()

        with l1:

            with l1:

                pass

    def test_another_process(self):

        l1 = build_lock()

        process = OtherProcess(l1)

        with l1:

            process.start()

            process.join()

        self.assertIsInstance(process.queue.get(), ProcessLockError)

    def test_another_process_blocking(self):

        l1 = build_lock(blocking=True)

        l2 = build_lock(blocking=True)

        process = OtherProcess(l1)

        target = l1.target

        with l2:

            process.start()

        process.join()

        self.assertEqual(process.queue.empty(), True)

        self.assertPathDoesNotExist(target)

    def test_another_thread(self):

        l1 = build_lock()

        thread = OtherThread(l1)

        with l1:

            thread.start()

            thread.join()

        self.assertIsInstance(thread.queue.get(), ThreadLockError)