2 # VPP Unix Domain Socket Transport.
16 class VppTransportSocketIOError(IOError):
20 class VppTransport(object):
21 VppTransportSocketIOError = VppTransportSocketIOError
23 def __init__(self, parent, read_timeout, server_address):
24 self.connected = False
25 self.read_timeout = read_timeout if read_timeout > 0 else 1
27 self.server_address = server_address
28 self.header = struct.Struct('>QII')
29 self.message_table = {}
30 self.sque = multiprocessing.Queue()
31 self.q = multiprocessing.Queue()
32 self.message_thread = None # Will be set on connect().
34 def msg_thread_func(self):
37 rlist, _, _ = select.select([self.socket,
38 self.sque._reader], [], [])
41 logging.error('select failed')
46 if r == self.sque._reader:
51 elif r == self.socket:
60 # Put either to local queue or if context == 0
62 if self.parent.has_context(msg):
65 self.parent.msg_handler_async(msg)
67 raise VppTransportSocketIOError(
68 2, 'Unknown response from select')
70 def connect(self, name, pfx, msg_handler, rx_qlen):
72 if self.message_thread is not None:
74 "PAPI socket transport connect: You need to disconnect first.")
75 self.message_thread = threading.Thread(target=self.msg_thread_func)
78 self.socket = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
79 self.socket.settimeout(self.read_timeout)
81 # Connect the socket to the port where the server is listening
83 self.socket.connect(self.server_address)
84 except socket.error as msg:
85 logging.error("{} on socket {}".format(msg, self.server_address))
89 # Initialise sockclnt_create
90 sockclnt_create = self.parent.messages['sockclnt_create']
91 sockclnt_create_reply = self.parent.messages['sockclnt_create_reply']
93 args = {'_vl_msg_id': 15,
96 b = sockclnt_create.pack(args)
99 hdr, length = self.parent.header.unpack(msg, 0)
101 raise VppTransportSocketIOError('Invalid reply message')
103 r, length = sockclnt_create_reply.unpack(msg)
104 self.socket_index = r.index
105 for m in r.message_table:
106 n = m.name.rstrip(b'\x00\x13')
107 self.message_table[n] = m.index
109 self.message_thread.daemon = True
110 self.message_thread.start()
114 def disconnect(self):
115 # TODO: Should we detect if user forgot to connect first?
117 try: # Might fail, if VPP closes socket before packet makes it out
118 rv = self.parent.api.sockclnt_delete(index=self.socket_index)
121 self.connected = False
123 self.sque.put(True) # Terminate listening thread
124 self.message_thread.join()
125 # Allow additional connect() calls.
126 self.message_thread = None
136 raise NotImplementedError
138 def get_callback(self, do_async):
141 def get_msg_index(self, name):
143 return self.message_table[name]
147 def msg_table_max_index(self):
148 return len(self.message_table)
150 def write(self, buf):
151 """Send a binary-packed message to VPP."""
152 if not self.connected:
153 raise VppTransportSocketIOError(1, 'Not connected')
156 header = self.header.pack(0, len(buf), 0)
157 n = self.socket.send(header)
158 n = self.socket.send(buf)
161 hdr = self.socket.recv(16)
164 (_, l, _) = self.header.unpack(hdr) # If at head of message
166 # Read rest of message
167 msg = self.socket.recv(l)
171 view = memoryview(buf)
176 nbytes = self.socket.recv_into(view, left)
182 raise VppTransportSocketIOError(1, 'Unknown socket read error')
185 if not self.connected:
186 raise VppTransportSocketIOError(1, 'Not connected')
188 return self.q.get(True, self.read_timeout)