1*a325d9c4SApple OSS Distributionsimport logging 2*a325d9c4SApple OSS Distributionsimport socket 3*a325d9c4SApple OSS Distributionsimport select 4*a325d9c4SApple OSS Distributions 5*a325d9c4SApple OSS Distributionsclass Interface(object): 6*a325d9c4SApple OSS Distributions """Basic communication interface.""" 7*a325d9c4SApple OSS Distributions def __init__(self, host_cfg, portnum): 8*a325d9c4SApple OSS Distributions super(Interface, self).__init__() 9*a325d9c4SApple OSS Distributions self.host_cfg = host_cfg 10*a325d9c4SApple OSS Distributions self.portnum = portnum 11*a325d9c4SApple OSS Distributions self.pkt_size = 8192 12*a325d9c4SApple OSS Distributions self.socket = None 13*a325d9c4SApple OSS Distributions self.isblocking = True 14*a325d9c4SApple OSS Distributions logging.debug("created %s" % str(self)) 15*a325d9c4SApple OSS Distributions 16*a325d9c4SApple OSS Distributions def connect(self): 17*a325d9c4SApple OSS Distributions self.socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM) 18*a325d9c4SApple OSS Distributions self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) 19*a325d9c4SApple OSS Distributions self.socket.bind((self.host_cfg, self.portnum)) 20*a325d9c4SApple OSS Distributions logging.debug("Initializing network interface for communication host: %s:%d", self.host_cfg, self.portnum) 21*a325d9c4SApple OSS Distributions self.socket.listen(5) 22*a325d9c4SApple OSS Distributions num_retries = 3 23*a325d9c4SApple OSS Distributions while num_retries > 0: 24*a325d9c4SApple OSS Distributions ra,wa,ea = select.select([self.socket], [], [], 30) 25*a325d9c4SApple OSS Distributions if not ra: 26*a325d9c4SApple OSS Distributions num_retries -= 1 27*a325d9c4SApple OSS Distributions logging.warning("timeout: select returned empty list. retrying..") 28*a325d9c4SApple OSS Distributions continue 29*a325d9c4SApple OSS Distributions self.connection, addr = self.socket.accept() 30*a325d9c4SApple OSS Distributions logging.info("Connected to client from %s" % str(addr)) 31*a325d9c4SApple OSS Distributions return True 32*a325d9c4SApple OSS Distributions logging.error("Failed to connect. Exiting after multiple attempts.") 33*a325d9c4SApple OSS Distributions return False 34*a325d9c4SApple OSS Distributions 35*a325d9c4SApple OSS Distributions def read(self): 36*a325d9c4SApple OSS Distributions if self.isblocking: 37*a325d9c4SApple OSS Distributions #BUG TODO make this unblocking soon 38*a325d9c4SApple OSS Distributions #logging.warn("blocking read bug") 39*a325d9c4SApple OSS Distributions self.connection.settimeout(15) 40*a325d9c4SApple OSS Distributions self.isblocking = False 41*a325d9c4SApple OSS Distributions r_bytes = '' 42*a325d9c4SApple OSS Distributions try: 43*a325d9c4SApple OSS Distributions r_bytes = self.connection.recv(self.pkt_size) 44*a325d9c4SApple OSS Distributions except Exception, e: 45*a325d9c4SApple OSS Distributions #logging.debug("Found exception in recv. %s " % (str(e))) 46*a325d9c4SApple OSS Distributions pass 47*a325d9c4SApple OSS Distributions 48*a325d9c4SApple OSS Distributions return r_bytes 49*a325d9c4SApple OSS Distributions 50*a325d9c4SApple OSS Distributions def write(self, bytes): 51*a325d9c4SApple OSS Distributions if not self.isblocking: 52*a325d9c4SApple OSS Distributions self.connection.setblocking(1) 53*a325d9c4SApple OSS Distributions self.isblocking = True 54*a325d9c4SApple OSS Distributions return self.connection.send(bytes) 55*a325d9c4SApple OSS Distributions 56*a325d9c4SApple OSS Distributions def close(self): 57*a325d9c4SApple OSS Distributions if self.connection: 58*a325d9c4SApple OSS Distributions logging.debug('closing connection.') 59*a325d9c4SApple OSS Distributions self.connection.close() 60*a325d9c4SApple OSS Distributions return self.socket 61*a325d9c4SApple OSS Distributions 62*a325d9c4SApple OSS Distributions def __str__(self): 63*a325d9c4SApple OSS Distributions return "interface: %s %d" % (self.host_cfg, self.portnum) 64