def acquire(self, delay=0.01):
if delay < 0:
raise ValueError("Delay must be greater than or equal to zero")
basedir = os.path.dirname(self.fname)
if not os.path.exists(basedir):
fileutils.ensure_tree(basedir)
LOG.info(_LI('Created lock path: %s'), basedir)
# Open in append mode so we don't overwrite any potential contents of
# the target file. This eliminates the possibility of an attacker
# creating a symlink to an important file in our lock_path.
self.lockfile = open(self.fname, 'a')
start_time = time.time()
# Using non-blocking locks (with retries) since green threads are not
# patched to deal with blocking locking calls. Also upon reading the
# MSDN docs for locking(), it seems to have a 'laughable' 10
# attempts "blocking" mechanism.
do_acquire = _lock_retry(delay=delay,
filename=self.fname)(self.trylock)
do_acquire()
self.acquire_time = time.time()
LOG.debug('Acquired file lock "%s" after waiting %0.3fs', self.fname,
(self.acquire_time - start_time))
return True
def acquire(self, delay=0.01):
if delay < 0:
raise ValueError("Delay must be greater than or equal to zero")
basedir = os.path.dirname(self.fname)
if not os.path.exists(basedir):
fileutils.ensure_tree(basedir)
LOG.info(_LI('Created lock path: %s'), basedir)
# Open in append mode so we don't overwrite any potential contents of
# the target file. This eliminates the possibility of an attacker
# creating a symlink to an important file in our lock_path.
self.lockfile = open(self.fname, 'a')
start_time = time.time()
# Using non-blocking locks (with retries) since green threads are not
# patched to deal with blocking locking calls. Also upon reading the
# MSDN docs for locking(), it seems to have a 'laughable' 10
# attempts "blocking" mechanism.
do_acquire = _lock_retry(delay=delay,
filename=self.fname)(self.trylock)
do_acquire()
self.acquire_time = time.time()
LOG.debug('Acquired file lock "%s" after waiting %0.3fs',
self.fname, (self.acquire_time - start_time))
return True
def remove_external_lock_file(name, lock_file_prefix=None, lock_path=None,
semaphores=None):
"""Remove an external lock file when it's not used anymore
This will be helpful when we have a lot of lock files
"""
with internal_lock(name, semaphores=semaphores):
lock_file_path = _get_lock_path(name, lock_file_prefix, lock_path)
try:
os.remove(lock_file_path)
except OSError:
LOG.info(_LI('Failed to remove file %(file)s'),
{'file': lock_file_path})
def remove_external_lock_file(name, lock_file_prefix=None, lock_path=None,
semaphores=None):
"""Remove an external lock file when it's not used anymore
This will be helpful when we have a lot of lock files
"""
with internal_lock(name, semaphores=semaphores):
lock_file_path = _get_lock_path(name, lock_file_prefix, lock_path)
try:
os.remove(lock_file_path)
except OSError:
LOG.info(_LI('Failed to remove file %(file)s'),
{'file': lock_file_path})