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.daemon is not None:
74 "PAPI socket transport connect: You need to disconnect first.")
75 self.message_thread.daemon = threading.Thread(
76 target=self.msg_thread_func)
79 self.socket = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
80 self.socket.settimeout(self.read_timeout)
82 # Connect the socket to the port where the server is listening
84 self.socket.connect(self.server_address)
85 except socket.error as msg:
86 logging.error("{} on socket {}".format(msg, self.server_address))
90 # Initialise sockclnt_create
91 sockclnt_create = self.parent.messages['sockclnt_create']
92 sockclnt_create_reply = self.parent.messages['sockclnt_create_reply']
94 args = {'_vl_msg_id': 15,
97 b = sockclnt_create.pack(args)
100 hdr, length = self.parent.header.unpack(msg, 0)
102 raise VppTransportSocketIOError('Invalid reply message')
104 r, length = sockclnt_create_reply.unpack(msg)
105 self.socket_index = r.index
106 for m in r.message_table:
107 n = m.name.rstrip(b'\x00\x13')
108 self.message_table[n] = m.index
110 self.message_thread.daemon = True
111 self.message_thread.start()
115 def disconnect(self):
116 # TODO: Should we detect if user forgot to connect first?
118 try: # Might fail, if VPP closes socket before packet makes it out
119 rv = self.parent.api.sockclnt_delete(index=self.socket_index)
122 self.connected = False
124 self.sque.put(True) # Terminate listening thread
125 self.message_thread.join()
126 # Allow additional connect() calls.
127 self.message_thread = None
137 raise NotImplementedError
139 def get_callback(self, do_async):
142 def get_msg_index(self, name):
144 return self.message_table[name]
148 def msg_table_max_index(self):
149 return len(self.message_table)
151 def write(self, buf):
152 """Send a binary-packed message to VPP."""
153 if not self.connected:
154 raise VppTransportSocketIOError(1, 'Not connected')
157 header = self.header.pack(0, len(buf), 0)
158 n = self.socket.send(header)
159 n = self.socket.send(buf)
162 hdr = self.socket.recv(16)
165 (_, l, _) = self.header.unpack(hdr) # If at head of message
167 # Read rest of message
168 msg = self.socket.recv(l)
172 view = memoryview(buf)
177 nbytes = self.socket.recv_into(view, left)
183 raise VPPTransportSocketIOError(1, 'Unknown socket read error')
186 if not self.connected:
187 raise VppTransportSocketIOError(1, 'Not connected')
189 return self.q.get(True, self.read_timeout)