2 # VPP Unix Domain Socket Transport.
13 class VppTransport(object):
14 def __init__(self, parent, read_timeout, server_address):
15 self.connected = False
16 self.read_timeout = read_timeout if read_timeout > 0 else 1
18 self.server_address = server_address
19 self.header = struct.Struct('>QII')
20 self.message_table = {}
21 self.sque = multiprocessing.Queue()
22 self.q = multiprocessing.Queue()
23 self.message_thread = threading.Thread(target=self.msg_thread_func)
25 def msg_thread_func(self):
28 rlist, _, _ = select.select([self.socket,
29 self.sque._reader], [], [])
32 logging.error('select failed')
37 if r == self.sque._reader:
42 elif r == self.socket:
51 # Put either to local queue or if context == 0
53 r = self.parent.decode_incoming_msg(msg)
54 if hasattr(r, 'context') and r.context > 0:
57 self.parent.msg_handler_async(msg)
59 raise IOError(2, 'Unknown response from select')
61 def connect(self, name, pfx, msg_handler, rx_qlen):
64 self.socket = socket.socket(socket.AF_UNIX, socket.SOCK_SEQPACKET)
65 self.socket.settimeout(self.read_timeout)
67 # Connect the socket to the port where the server is listening
69 self.socket.connect(self.server_address)
70 except socket.error as msg:
71 logging.error("{} on socket {}".format(msg, self.server_address))
75 # Initialise sockclnt_create
76 sockclnt_create = self.parent.messages['sockclnt_create']
77 sockclnt_create_reply = self.parent.messages['sockclnt_create_reply']
79 args = {'_vl_msg_id': 15,
82 b = sockclnt_create.pack(args)
85 hdr, length = self.parent.header.unpack(msg, 0)
87 raise IOError('Invalid reply message')
89 r, length = sockclnt_create_reply.unpack(msg)
90 self.socket_index = r.index
91 for m in r.message_table:
92 n = m.name.rstrip(b'\x00\x13')
93 self.message_table[n] = m.index
95 self.message_thread.daemon = True
96 self.message_thread.start()
100 def disconnect(self):
102 try: # Might fail, if VPP closes socket before packet makes it out
103 rv = self.parent.api.sockclnt_delete(index=self.socket_index)
106 self.connected = False
108 self.sque.put(True) # Terminate listening thread
109 self.message_thread.join()
121 def get_callback(self, do_async):
124 def get_msg_index(self, name):
126 return self.message_table[name]
130 def msg_table_max_index(self):
131 return len(self.message_table)
133 def write(self, buf):
134 """Send a binary-packed message to VPP."""
135 if not self.connected:
136 raise IOError(1, 'Not connected')
139 header = self.header.pack(0, len(buf), 0)
140 n = self.socket.send(header)
141 n = self.socket.send(buf)
146 msg = self.socket.recv(4096)
149 except socket.error as message:
150 logging.error(message)
153 (_, l, _) = self.header.unpack(msg[:16])
156 buf = bytearray(l + 16)
157 view = memoryview(buf)
160 # Read rest of message
161 remaining_bytes = l - 4096 + 16
162 while remaining_bytes > 0:
163 bytes_to_read = (remaining_bytes if remaining_bytes
165 nbytes = self.socket.recv_into(view, bytes_to_read)
167 logging.error('recv failed')
170 remaining_bytes -= nbytes
176 if not self.connected:
177 raise IOError(1, 'Not connected')
179 return self.q.get(True, self.read_timeout)