storelocking: avoid raising a NotLocked exception while releasing the…

… lock while handling an exception

src/borg/storelocking.py

@@ -84,8 +84,11 @@ def __init__(self, store, exclusive=False, sleep=None, timeout=1.0, stale=30 * 6
  def __enter__(self):
  return self.acquire()
 
- def __exit__(self, *exc):
- self.release()
+ def __exit__(self, exc_type, exc_val, exc_tb):
+ ignore_not_found = exc_type is not None
+ # if there was an exception, try to release the lock,
+ # but don't raise another exception while trying if it was not there.
+ self.release(ignore_not_found=ignore_not_found)
 
  def __repr__(self):
  return f"<{self.__class__.__name__}: {self.id!r}>"
@@ -194,15 +197,19 @@ def acquire(self):
  logger.debug("LOCK-ACQUIRE: timeout while trying to acquire a lock.")
  raise LockTimeout(str(self.store))
 
- def release(self):
+ def release(self, *, ignore_not_found=False):
+ self.last_refresh_dt = None
  locks = self._find_locks(only_mine=True)
  if not locks:
- raise NotLocked(str(self.store))
+ if ignore_not_found:
+ logger.debug("LOCK-RELEASE: trying to release lock, but none was found.")
+ return
+ else:
+ raise NotLocked(str(self.store))
  assert len(locks) == 1
  lock = locks[0]
  logger.debug(f"LOCK-RELEASE: releasing lock: {lock}.")
  self._delete_lock(lock["key"], ignore_not_found=True)
- self.last_refresh_dt = None
 
  def got_exclusive_lock(self):
  locks = self._find_locks(only_mine=True, only_exclusive=True)