can't get a connection when using connection pool if max_open_connections=0

[newdefence]

File: tornado_mysql/pools.py
`

class Pool(object):

    def _get_conn(self):

`
my code:
mypool = tornado_mysql.pool.Pool(**{host:"localhost"})

then self._free_conn if empty forever, equal to false
self.max_open = 0, equal to false

now, the pool is waiting for a connection, but there is no chance to create a connection.

thanks to fix the bug.

[methane]

Which version did you use???
See 4951ec2