Pool must release its semaphore on connection failure. PYTHON-580

Author: ajdavis

pymongo/pool.py

@@ -324,28 +324,33 @@ def get_socket(self, pair=None, force=False):
  elif not self._socket_semaphore.acquire(True, self.wait_queue_timeout):
  self._raise_wait_queue_timeout()
 
- sock_info, from_pool = None, None
+ # We've now acquired the semaphore and must release it on error.
  try:
+ sock_info, from_pool = None, None
  try:
- # set.pop() isn't atomic in Jython less than 2.7, see
- # http://bugs.jython.org/issue1854
- self.lock.acquire()
- sock_info, from_pool = self.sockets.pop(), True
- finally:
- self.lock.release()
- except KeyError:
- sock_info, from_pool = self.connect(pair), False
-
- if from_pool:
- sock_info = self._check(sock_info, pair)
-
- sock_info.forced = forced
-
- if req_state == NO_SOCKET_YET:
- # start_request has been called but we haven't assigned a socket to
- # the request yet. Let's use this socket for this request until
- # end_request.
- self._set_request_state(sock_info)
+ try:
+ # set.pop() isn't atomic in Jython less than 2.7, see
+ # http://bugs.jython.org/issue1854
+ self.lock.acquire()
+ sock_info, from_pool = self.sockets.pop(), True
+ finally:
+ self.lock.release()
+ except KeyError:
+ sock_info, from_pool = self.connect(pair), False
+
+ if from_pool:
+ sock_info = self._check(sock_info, pair)
+
+ sock_info.forced = forced
+
+ if req_state == NO_SOCKET_YET:
+ # start_request has been called but we haven't assigned a
+ # socket to the request yet. Let's use this socket for this
+ # request until end_request.
+ self._set_request_state(sock_info)
+ except:
+ self._socket_semaphore.release()
+ raise
 
  sock_info.last_checkout = time.time()
  return sock_info