socket leakage

[robustor123]

when reconnect is needed, previous socket is not closed.
as following modification, the _mosquitto_socket_close() function should be called.
with this fix, I can remove socket leakage problem in mosquitto library.

static int _mosquitto_reconnect(struct mosquitto *mosq, bool blocking)
{
...
#ifdef WITH_SOCKS
if(mosq->socks5_host){
rc = _mosquitto_socket_connect(mosq, mosq->socks5_host, mosq->socks5_port, mosq->bind_address, blocking);
}else
#endif
{
if(mosq->sock != INVALID_SOCKET){
_mosquitto_socket_close(mosq); //close socket
}
rc = _mosquitto_socket_connect(mosq, mosq->host, mosq->port, mosq->bind_address, blocking);
}

[thlassche]

Pull request opened for this #307

[ralight]

Thanks both, this is now fixed in the fixes branch.