def test_rmlinkError(self):
"""
An exception raised by L{rmlink} other than C{ENOENT} is passed up
to the caller of L{FilesystemLock.lock}.
"""
def fakeRmlink(name):
raise OSError(errno.ENOSYS, None)
self.patch(lockfile, 'rmlink', fakeRmlink)
def fakeKill(pid, signal):
if signal != 0:
raise OSError(errno.EPERM, None)
if pid == 43125:
raise OSError(errno.ESRCH, None)
self.patch(lockfile, 'kill', fakeKill)
lockf = self.mktemp()
# Make it appear locked so it has to use readlink
lockfile.symlink(str(43125), lockf)
lock = lockfile.FilesystemLock(lockf)
exc = self.assertRaises(OSError, lock.lock)
self.assertEqual(exc.errno, errno.ENOSYS)
self.assertFalse(lock.locked)
def test_lockReleasedBeforeCheck(self):
"""
If the lock is initially held but then released before it can be
examined to determine if the process which held it still exists, it is
acquired and the C{clean} and C{locked} attributes are set to C{True}.
"""
def fakeReadlink(name):
# Pretend to be another process releasing the lock.
lockfile.rmlink(lockf)
# Fall back to the real implementation of readlink.
readlinkPatch.restore()
return lockfile.readlink(name)
readlinkPatch = self.patch(lockfile, 'readlink', fakeReadlink)
def fakeKill(pid, signal):
if signal != 0:
raise OSError(errno.EPERM, None)
if pid == 43125:
raise OSError(errno.ESRCH, None)
self.patch(lockfile, 'kill', fakeKill)
lockf = self.mktemp()
lock = lockfile.FilesystemLock(lockf)
lockfile.symlink(str(43125), lockf)
self.assertTrue(lock.lock())
self.assertTrue(lock.clean)
self.assertTrue(lock.locked)
def test_lockReleasedBeforeCheck(self):
"""
If the lock is initially held but then released before it can be
examined to determine if the process which held it still exists, it is
acquired and the C{clean} and C{locked} attributes are set to C{True}.
"""
def fakeReadlink(name):
# Pretend to be another process releasing the lock.
lockfile.rmlink(lockf)
# Fall back to the real implementation of readlink.
readlinkPatch.restore()
return lockfile.readlink(name)
readlinkPatch = self.patch(lockfile, 'readlink', fakeReadlink)
def fakeKill(pid, signal):
if signal != 0:
raise OSError(errno.EPERM, None)
if pid == 43125:
raise OSError(errno.ESRCH, None)
self.patch(lockfile, 'kill', fakeKill)
lockf = self.mktemp()
lock = lockfile.FilesystemLock(lockf)
lockfile.symlink(str(43125), lockf)
self.assertTrue(lock.lock())
self.assertTrue(lock.clean)
self.assertTrue(lock.locked)
def test_lockCleanedUpConcurrently(self):
"""
If a second process cleans up the lock after a first one checks the
lock and finds that no process is holding it, the first process does
not fail when it tries to clean up the lock.
"""
def fakeRmlink(name):
rmlinkPatch.restore()
# Pretend to be another process cleaning up the lock.
lockfile.rmlink(lockf)
# Fall back to the real implementation of rmlink.
return lockfile.rmlink(name)
rmlinkPatch = self.patch(lockfile, 'rmlink', fakeRmlink)
def fakeKill(pid, signal):
if signal != 0:
raise OSError(errno.EPERM, None)
if pid == 43125:
raise OSError(errno.ESRCH, None)
self.patch(lockfile, 'kill', fakeKill)
lockf = self.mktemp()
lock = lockfile.FilesystemLock(lockf)
lockfile.symlink(str(43125), lockf)
self.assertTrue(lock.lock())
self.assertTrue(lock.clean)
self.assertTrue(lock.locked)
def test_lockCleanedUpConcurrently(self):
"""
If a second process cleans up the lock after a first one checks the
lock and finds that no process is holding it, the first process does
not fail when it tries to clean up the lock.
"""
def fakeRmlink(name):
rmlinkPatch.restore()
# Pretend to be another process cleaning up the lock.
lockfile.rmlink(lockf)
# Fall back to the real implementation of rmlink.
return lockfile.rmlink(name)
rmlinkPatch = self.patch(lockfile, 'rmlink', fakeRmlink)
def fakeKill(pid, signal):
if signal != 0:
raise OSError(errno.EPERM, None)
if pid == 43125:
raise OSError(errno.ESRCH, None)
self.patch(lockfile, 'kill', fakeKill)
lockf = self.mktemp()
lock = lockfile.FilesystemLock(lockf)
lockfile.symlink(str(43125), lockf)
self.assertTrue(lock.lock())
self.assertTrue(lock.clean)
self.assertTrue(lock.locked)
def test_rmlinkError(self):
"""
An exception raised by L{rmlink} other than C{ENOENT} is passed up
to the caller of L{FilesystemLock.lock}.
"""
def fakeRmlink(name):
raise OSError(errno.ENOSYS, None)
self.patch(lockfile, 'rmlink', fakeRmlink)
def fakeKill(pid, signal):
if signal != 0:
raise OSError(errno.EPERM, None)
if pid == 43125:
raise OSError(errno.ESRCH, None)
self.patch(lockfile, 'kill', fakeKill)
lockf = self.mktemp()
# Make it appear locked so it has to use readlink
lockfile.symlink(str(43125), lockf)
lock = lockfile.FilesystemLock(lockf)
exc = self.assertRaises(OSError, lock.lock)
self.assertEqual(exc.errno, errno.ENOSYS)
self.assertFalse(lock.locked)
def test_symlinkEEXIST(self):
"""
L{lockfile.symlink} raises L{OSError} with C{errno} set to L{EEXIST}
when an attempt is made to create a symlink which already exists.
"""
name = self.mktemp()
lockfile.symlink('foo', name)
exc = self.assertRaises(OSError, lockfile.symlink, 'foo', name)
self.assertEqual(exc.errno, errno.EEXIST)
def test_unlockOther(self):
"""
L{FilesystemLock.unlock} raises L{ValueError} if called for a lock
which is held by a different process.
"""
lockf = self.mktemp()
lockfile.symlink(str(os.getpid() + 1), lockf)
lock = lockfile.FilesystemLock(lockf)
self.assertRaises(ValueError, lock.unlock)
def test_symlinkEEXIST(self):
"""
L{lockfile.symlink} raises L{OSError} with C{errno} set to L{EEXIST}
when an attempt is made to create a symlink which already exists.
"""
name = self.mktemp()
lockfile.symlink('foo', name)
exc = self.assertRaises(OSError, lockfile.symlink, 'foo', name)
self.assertEqual(exc.errno, errno.EEXIST)
def test_unlockOther(self):
"""
L{FilesystemLock.unlock} raises L{ValueError} if called for a lock
which is held by a different process.
"""
lockf = self.mktemp()
lockfile.symlink(str(os.getpid() + 1), lockf)
lock = lockfile.FilesystemLock(lockf)
self.assertRaises(ValueError, lock.unlock)
def _readlinkErrorTest(self, exceptionType, errno):
def fakeReadlink(name):
raise exceptionType(errno, None)
self.patch(lockfile, 'readlink', fakeReadlink)
lockf = self.mktemp()
# Make it appear locked so it has to use readlink
lockfile.symlink(str(43125), lockf)
lock = lockfile.FilesystemLock(lockf)
exc = self.assertRaises(exceptionType, lock.lock)
self.assertEqual(exc.errno, errno)
self.assertFalse(lock.locked)
def _readlinkErrorTest(self, exceptionType, errno):
def fakeReadlink(name):
raise exceptionType(errno, None)
self.patch(lockfile, 'readlink', fakeReadlink)
lockf = self.mktemp()
# Make it appear locked so it has to use readlink
lockfile.symlink(str(43125), lockf)
lock = lockfile.FilesystemLock(lockf)
exc = self.assertRaises(exceptionType, lock.lock)
self.assertEqual(exc.errno, errno)
self.assertFalse(lock.locked)
def test_lockReleasedDuringAcquireReadlink(self):
"""
If the lock is initially held but is released while an attempt
is made to acquire it, the lock attempt fails and
L{FilesystemLock.lock} returns C{False}.
"""
def fakeReadlink(name):
# While another process is doing os.rmdir which the
# Windows implementation of rmlink does, a readlink call
# will fail with EACCES.
raise IOError(errno.EACCES, None)
readlinkPatch = self.patch(lockfile, 'readlink', fakeReadlink)
lockf = self.mktemp()
lock = lockfile.FilesystemLock(lockf)
lockfile.symlink(str(43125), lockf)
self.assertFalse(lock.lock())
self.assertFalse(lock.locked)
def test_lockReleasedDuringAcquireReadlink(self):
"""
If the lock is initially held but is released while an attempt
is made to acquire it, the lock attempt fails and
L{FilesystemLock.lock} returns C{False}.
"""
def fakeReadlink(name):
# While another process is doing os.rmdir which the
# Windows implementation of rmlink does, a readlink call
# will fail with EACCES.
raise IOError(errno.EACCES, None)
readlinkPatch = self.patch(lockfile, 'readlink', fakeReadlink)
lockf = self.mktemp()
lock = lockfile.FilesystemLock(lockf)
lockfile.symlink(str(43125), lockf)
self.assertFalse(lock.lock())
self.assertFalse(lock.locked)
def test_killError(self):
"""
If L{kill} raises an exception other than L{OSError} with errno set to
C{ESRCH}, the exception is passed up to the caller of
L{FilesystemLock.lock}.
"""
def fakeKill(pid, signal):
raise OSError(errno.EPERM, None)
self.patch(lockfile, 'kill', fakeKill)
lockf = self.mktemp()
# Make it appear locked so it has to use readlink
lockfile.symlink(str(43125), lockf)
lock = lockfile.FilesystemLock(lockf)
exc = self.assertRaises(OSError, lock.lock)
self.assertEqual(exc.errno, errno.EPERM)
self.assertFalse(lock.locked)
def test_killError(self):
"""
If L{kill} raises an exception other than L{OSError} with errno set to
C{ESRCH}, the exception is passed up to the caller of
L{FilesystemLock.lock}.
"""
def fakeKill(pid, signal):
raise OSError(errno.EPERM, None)
self.patch(lockfile, 'kill', fakeKill)
lockf = self.mktemp()
# Make it appear locked so it has to use readlink
lockfile.symlink(str(43125), lockf)
lock = lockfile.FilesystemLock(lockf)
exc = self.assertRaises(OSError, lock.lock)
self.assertEqual(exc.errno, errno.EPERM)
self.assertFalse(lock.locked)
def test_uncleanlyAcquire(self):
"""
If a lock was held by a process which no longer exists, it can be
acquired, the C{clean} attribute is set to C{False}, and the
C{locked} attribute is set to C{True}.
"""
owner = 12345
def fakeKill(pid, signal):
if signal != 0:
raise OSError(errno.EPERM, None)
if pid == owner:
raise OSError(errno.ESRCH, None)
lockf = self.mktemp()
self.patch(lockfile, 'kill', fakeKill)
lockfile.symlink(str(owner), lockf)
lock = lockfile.FilesystemLock(lockf)
self.assertTrue(lock.lock())
self.assertFalse(lock.clean)
self.assertTrue(lock.locked)
self.assertEqual(lockfile.readlink(lockf), str(os.getpid()))
def test_uncleanlyAcquire(self):
"""
If a lock was held by a process which no longer exists, it can be
acquired, the C{clean} attribute is set to C{False}, and the
C{locked} attribute is set to C{True}.
"""
owner = 12345
def fakeKill(pid, signal):
if signal != 0:
raise OSError(errno.EPERM, None)
if pid == owner:
raise OSError(errno.ESRCH, None)
lockf = self.mktemp()
self.patch(lockfile, 'kill', fakeKill)
lockfile.symlink(str(owner), lockf)
lock = lockfile.FilesystemLock(lockf)
self.assertTrue(lock.lock())
self.assertFalse(lock.clean)
self.assertTrue(lock.locked)
self.assertEqual(lockfile.readlink(lockf), str(os.getpid()))
