def lock(self, raise_on_fail=True):
# type: (bool) -> bool
"""
Get locks to prevent concurrent calls.
:param bool raise_on_fail: Raise :py:class:`LockError` instead of returning `False`.
:returns: `True` if all locks were are acquired, `False` otherwise.
:rtype: bool
:raises LockError: if the lock cannot be acquired.
"""
if self.is_locked():
return True
self.lock_fd = get_lock('univention-lib-package-manager',
nonblocking=True)
return_value = self.lock_fd is not None
if return_value is True:
# get apt lock; taken from dist-packages/apt/cache.py
lockfile = apt_pkg.config.find_dir("Dir::Cache::Archives") + "lock"
self.apt_lock_fd = apt_pkg.get_lock(lockfile)
if self.apt_lock_fd < 0:
return_value = False
if return_value is False:
if raise_on_fail:
raise LockError(_('Failed to lock'))
return return_value
def lock(self, raise_on_fail=True):
self.lock_fd = get_lock('univention-lib-package-manager', nonblocking=True)
return_value = self.lock_fd is not None
if return_value is False:
if raise_on_fail:
raise LockError(_('Failed to lock'))
return return_value
def lock(self, raise_on_fail=True):
self.lock_fd = get_lock('univention-lib-package-manager',
nonblocking=True)
return_value = self.lock_fd is not None
if return_value is False:
if raise_on_fail:
raise LockError(_('Failed to lock'))
return return_value
def save(self):
# remove all sections
for sec in self.sections():
self.remove_section(sec)
for lesson in self.lessons:
self.add_section(lesson.name)
self.set(lesson.name, 'begin', str(lesson.begin))
self.set(lesson.name, 'end', str(lesson.end))
lock = locking.get_lock('ucs-school-lib-schoollessons')
with open(LESSONS_FILE, 'w') as fd:
shutil.copyfile(LESSONS_FILE, LESSONS_BACKUP)
self.write(fd)
locking.release_lock(lock)
def lock(self, raise_on_fail=True):
if self.is_locked():
return True
self.lock_fd = get_lock('univention-lib-package-manager',
nonblocking=True)
return_value = self.lock_fd is not None
if return_value is True:
# get apt lock; taken from dist-packages/apt/cache.py
lockfile = apt_pkg.config.find_dir("Dir::Cache::Archives") + "lock"
self.apt_lock_fd = apt_pkg.get_lock(lockfile)
if self.apt_lock_fd < 0:
return_value = False
if return_value is False:
if raise_on_fail:
raise LockError(_('Failed to lock'))
return return_value
