[webkitcorepy] Move FileLock from webkitpy

https://bugs.webkit.org/show_bug.cgi?id=230320
<rdar://problem/83168826>

Reviewed by Dewei Zhu.

Move FileLock from webkitpy into webkitcorepy, implement FileLock as a more
modern Python API.

* Scripts/libraries/webkitcorepy/setup.py: Bump version.
* Scripts/libraries/webkitcorepy/webkitcorepy/__init__.py: Ditto.
* Scripts/libraries/webkitcorepy/webkitcorepy/file_lock.py: Added.
(FileLock):
(FileLock.__init__):
(FileLock.acquired): Check if the current process has acquired the lock.
(FileLock.acquire): Attempt to acquire lockfile.
(FileLock.release): Release lockfile, if this process owns the lock.
(FileLock.__enter__): Invoke acquire.
(FileLock.__exit__): Invoke release.
* Scripts/libraries/webkitcorepy/webkitcorepy/mocks/__init__.py:
* Scripts/libraries/webkitcorepy/webkitcorepy/mocks/file_lock.py: Copied from Tools/Scripts/libraries/webkitcorepy/webkitcorepy/mocks/__init__.py.
(FileLock): Single-thread stub implementation of FileLock for testing without a filesystem.
* Scripts/libraries/webkitcorepy/webkitcorepy/tests/file_lock_unittest.py: Added.
(FileLockTestCase):
(FileLockTestCase.__init__):
(FileLockTestCase.setUp):
(FileLockTestCase.tearDown):
(FileLockTestCase.test_basic):
(FileLockTestCase.test_locked):
(FileLockTestCase.test_locked_timeout):
(FileLockTestCase.test_double):
* Scripts/webkitpy/common/system/file_lock.py: Removed.
* Scripts/webkitpy/common/system/file_lock_integrationtest.py: Removed.
* Scripts/webkitpy/common/system/systemhost.py:
(SystemHost.make_file_lock): Use webkitcorepy's FileLock.
* Scripts/webkitpy/common/system/systemhost_mock.py:
(MockSystemHost.make_file_lock): Use webkitcorepy's mocks.FileLock.
* Scripts/webkitpy/tool/commands/rebaseline.py:
(RebaselineTest._update_expectations_file): Use webkitcorepy's FileLock.


Canonical link: https://commits.webkit.org/241905@main
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@282770 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Tools/ChangeLog

@@ -1,3 +1,45 @@
+2021-09-20  Jonathan Bedard  <jbedard@apple.com>
+
+        [webkitcorepy] Move FileLock from webkitpy
+        https://bugs.webkit.org/show_bug.cgi?id=230320
+        <rdar://problem/83168826>
+
+        Reviewed by Dewei Zhu.
+
+        Move FileLock from webkitpy into webkitcorepy, implement FileLock as a more
+        modern Python API.
+
+        * Scripts/libraries/webkitcorepy/setup.py: Bump version.
+        * Scripts/libraries/webkitcorepy/webkitcorepy/__init__.py: Ditto.
+        * Scripts/libraries/webkitcorepy/webkitcorepy/file_lock.py: Added.
+        (FileLock):
+        (FileLock.__init__):
+        (FileLock.acquired): Check if the current process has acquired the lock.
+        (FileLock.acquire): Attempt to acquire lockfile.
+        (FileLock.release): Release lockfile, if this process owns the lock.
+        (FileLock.__enter__): Invoke acquire.
+        (FileLock.__exit__): Invoke release.
+        * Scripts/libraries/webkitcorepy/webkitcorepy/mocks/__init__.py:
+        * Scripts/libraries/webkitcorepy/webkitcorepy/mocks/file_lock.py: Copied from Tools/Scripts/libraries/webkitcorepy/webkitcorepy/mocks/__init__.py.
+        (FileLock): Single-thread stub implementation of FileLock for testing without a filesystem.
+        * Scripts/libraries/webkitcorepy/webkitcorepy/tests/file_lock_unittest.py: Added.
+        (FileLockTestCase):
+        (FileLockTestCase.__init__):
+        (FileLockTestCase.setUp):
+        (FileLockTestCase.tearDown):
+        (FileLockTestCase.test_basic):
+        (FileLockTestCase.test_locked):
+        (FileLockTestCase.test_locked_timeout):
+        (FileLockTestCase.test_double):
+        * Scripts/webkitpy/common/system/file_lock.py: Removed.
+        * Scripts/webkitpy/common/system/file_lock_integrationtest.py: Removed.
+        * Scripts/webkitpy/common/system/systemhost.py:
+        (SystemHost.make_file_lock): Use webkitcorepy's FileLock.
+        * Scripts/webkitpy/common/system/systemhost_mock.py:
+        (MockSystemHost.make_file_lock): Use webkitcorepy's mocks.FileLock.
+        * Scripts/webkitpy/tool/commands/rebaseline.py:
+        (RebaselineTest._update_expectations_file): Use webkitcorepy's FileLock.
+
 2021-09-20  Brent Fulgham  <bfulgham@apple.com>
 
         Remove XSS Auditor: Part 1 (Turn off by default)

Tools/Scripts/libraries/webkitcorepy/setup.py

@@ -30,7 +30,7 @@ def readme():
 
 setup(
     name='webkitcorepy',
-    version='0.10.3',
+    version='0.11.0',
     description='Library containing various Python support classes and functions.',
     long_description=readme(),
     classifiers=[

Tools/Scripts/libraries/webkitcorepy/webkitcorepy/__init__.py

@@ -41,8 +41,9 @@
 from webkitcorepy.nested_fuzzy_dict import NestedFuzzyDict
 from webkitcorepy.call_by_need import CallByNeed
 from webkitcorepy.editor import Editor
+from webkitcorepy.file_lock import FileLock
 
-version = Version(0, 10, 3)
+version = Version(0, 11, 0)
 
 from webkitcorepy.autoinstall import Package, AutoInstall
 if sys.version_info > (3, 0):

Tools/Scripts/libraries/webkitcorepy/webkitcorepy/file_lock.py

@@ -0,0 +1,85 @@
+# Copyright (C) 2010 Gabor Rapcsanyi (rgabor@inf.u-szeged.hu), University of Szeged
+# Copyright (C) 2021 Apple Inc. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1.  Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2.  Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
+# EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+# DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+# ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+import os
+import sys
+import time
+
+if sys.platform.startswith('win'):
+    import msvcrt
+else:
+    import fcntl
+
+
+class FileLock(object):
+
+    def __init__(self, path, timeout=20):
+        self.path = path
+        self.timeout = timeout
+        self._descriptor = None
+
+    @property
+    def acquired(self):
+        return bool(self._descriptor)
+
+    def acquire(self):
+        if self._descriptor:
+            return True
+
+        descriptor = os.open(self.path, os.O_TRUNC | os.O_CREAT)
+        start_time = time.time()
+        while True:
+            try:
+                if sys.platform.startswith('win'):
+                    msvcrt.locking(descriptor, msvcrt.LK_NBLCK, 32)
+                else:
+                    fcntl.flock(descriptor, fcntl.LOCK_EX | fcntl.LOCK_NB)
+                self._descriptor = descriptor
+                return True
+
+            except IOError:
+                if time.time() - start_time > self.timeout:
+                    os.close(descriptor)
+                    self._descriptor = None
+                    return False
+                time.sleep(0.01)
+
+    def release(self):
+        try:
+            if self._descriptor:
+                if sys.platform.startswith('win'):
+                    msvcrt.locking(self._descriptor, msvcrt.LK_UNLCK, 32)
+                else:
+                    fcntl.flock(self._descriptor, fcntl.LOCK_UN)
+                os.close(self._descriptor)
+                self._descriptor = None
+            os.unlink(self.path)
+        except (IOError, OSError):
+            pass
+
+    def __enter__(self):
+        self.acquire()
+        return self
+
+    def __exit__(self, *args, **kwargs):
+        self.release()

Tools/Scripts/libraries/webkitcorepy/webkitcorepy/mocks/__init__.py

@@ -26,3 +26,4 @@
 
 from webkitcorepy.mocks.requests_ import Response, Requests
 from webkitcorepy.mocks.terminal import Terminal
+from webkitcorepy.mocks.file_lock import FileLock

Tools/Scripts/libraries/webkitcorepy/webkitcorepy/mocks/file_lock.py

@@ -0,0 +1,46 @@
+# Copyright (C) 2021 Apple Inc. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1.  Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2.  Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
+# EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+# DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+# ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
+class FileLock(object):
+    def __init__(self, path, timeout=20):
+        self.path = path
+        self.timeout = timeout
+        self._acquired = False
+
+    @property
+    def acquired(self):
+        return self._acquired
+
+    def acquire(self):
+        self._acquired = True
+        return True
+
+    def release(self):
+        self._acquired = False
+
+    def __enter__(self):
+        self.acquire()
+        return self
+
+    def __exit__(self, *args, **kwargs):
+        self.release()

Tools/Scripts/libraries/webkitcorepy/webkitcorepy/tests/file_lock_unittest.py

@@ -0,0 +1,115 @@
+# Copyright (C) 2021 Apple Inc. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1.  Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2.  Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
+# EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+# DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+# ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+import os
+import shutil
+import tempfile
+import time
+import unittest
+
+from webkitcorepy import FileLock, mocks
+
+
+class FileLockTestCase(unittest.TestCase):
+
+    def __init__(self, *args, **kwargs):
+        super(FileLockTestCase, self).__init__(*args, **kwargs)
+        self.path = None
+
+    def setUp(self):
+        self.path = tempfile.mkdtemp()
+
+    def tearDown(self):
+        shutil.rmtree(self.path, ignore_errors=True)
+
+    def test_basic(self):
+        path = os.path.join(self.path, 'example-{}.lock'.format(os.getpid()))
+        lock = FileLock(path, timeout=0)
+
+        self.assertFalse(lock.acquired)
+        with lock:
+            self.assertTrue(lock.acquired)
+        self.assertFalse(lock.acquired)
+
+        with lock:
+            self.assertTrue(lock.acquired)
+        self.assertFalse(lock.acquired)
+
+    def test_locked(self):
+        path = os.path.join(self.path, 'example-{}.lock'.format(os.getpid()))
+        lock_a = FileLock(path, timeout=0)
+        lock_b = FileLock(path, timeout=0)
+
+        self.assertFalse(lock_a.acquired)
+        self.assertFalse(lock_b.acquired)
+
+        with lock_a:
+            self.assertTrue(lock_a.acquired)
+            self.assertFalse(lock_b.acquired)
+
+            with lock_b:
+                self.assertTrue(lock_a.acquired)
+                self.assertFalse(lock_b.acquired)
+
+            self.assertTrue(lock_a.acquired)
+            self.assertFalse(lock_b.acquired)
+
+        self.assertFalse(lock_a.acquired)
+        self.assertFalse(lock_b.acquired)
+
+    def test_locked_timeout(self):
+        with mocks.Time:
+            path = os.path.join(self.path, 'example-{}.lock'.format(os.getpid()))
+            lock_a = FileLock(path, timeout=0)
+            lock_b = FileLock(path, timeout=30)
+
+            self.assertFalse(lock_a.acquired)
+            self.assertFalse(lock_b.acquired)
+
+            start_time = int(time.time())
+            with lock_a:
+                self.assertEqual(start_time, int(time.time()))
+                self.assertTrue(lock_a.acquired)
+                self.assertFalse(lock_b.acquired)
+
+                with lock_b:
+                    self.assertEqual(start_time + 30, int(time.time()))
+                    self.assertTrue(lock_a.acquired)
+                    self.assertFalse(lock_b.acquired)
+
+                self.assertTrue(lock_a.acquired)
+                self.assertFalse(lock_b.acquired)
+
+            self.assertFalse(lock_a.acquired)
+            self.assertFalse(lock_b.acquired)
+
+    def test_double(self):
+        path = os.path.join(self.path, 'example-{}.lock'.format(os.getpid()))
+        lock = FileLock(path, timeout=0)
+
+        self.assertFalse(lock.acquired)
+        with lock:
+            self.assertTrue(lock.acquired)
+            with lock:
+                self.assertTrue(lock.acquired)
+            self.assertFalse(lock.acquired)
+        self.assertFalse(lock.acquired)