3 # Copyright (c) 2016 Cisco and/or its affiliates.
4 # Licensed under the Apache License, Version 2.0 (the "License");
5 # you may not use this file except in compliance with the License.
6 # You may obtain a copy of the License at:
8 # http://www.apache.org/licenses/LICENSE-2.0
10 # Unless required by applicable law or agreed to in writing, software
11 # distributed under the License is distributed on an "AS IS" BASIS,
12 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 # See the License for the specific language governing permissions and
14 # limitations under the License.
17 from __future__ import print_function
18 import sys, os, logging, collections, struct, json, threading
19 logging.basicConfig(level=logging.DEBUG)
22 def eprint(*args, **kwargs):
23 print(*args, file=sys.stderr, **kwargs)
26 def __init__(self, apifiles):
30 self.buffersize = 10000
31 self.connected = False
32 self.header = struct.Struct('>HI')
38 self.apifile.append(file)
39 with open(file) as apidef_file:
40 api = json.load(apidef_file)
41 for t in api['types']:
42 self.add_type(t[0], t[1:])
44 for m in api['messages']:
45 self.add_message(m[0], m[1:])
48 if not 'control_ping' in self.messages:
49 raise ValueError(1, 'Error in JSON message definitions')
52 class ContextId(object):
58 get_context = ContextId()
61 print('Connected') if self.connected else print('Not Connected')
62 print('Read API definitions from', self.apifile)
64 def __struct (self, t, n = None, e = 0, vl = None):
65 base_types = { 'u8' : 'B',
78 return struct.Struct('>' + str(e) + 's')
80 # Fixed array of base type
81 return [e, struct.Struct('>' + base_types[t])]
83 # Variable length array
84 return [vl, struct.Struct('>s')] if t == 'u8' else [vl, struct.Struct('>' + base_types[t])]
86 return struct.Struct('>' + base_types[t])
88 if t in self.messages:
89 ### Return a list in case of array ###
91 return [e, lambda self, encode, buf, offset, args: (
92 self.__struct_type(encode, self.messages[t], buf, offset, args)
95 return [vl, lambda self, encode, buf, offset, args: (
96 self.__struct_type(encode, self.messages[t], buf, offset, args)
98 return lambda self, encode, buf, offset, args: (
99 self.__struct_type(encode, self.messages[t], buf, offset, args)
104 def __struct_type(self, encode, msgdef, buf, offset, kwargs):
106 return self.__struct_type_encode(msgdef, buf, offset, kwargs)
108 return self.__struct_type_decode(msgdef, buf, offset)
110 def __struct_type_encode(self, msgdef, buf, offset, kwargs):
113 for k,v in msgdef['args'].iteritems():
124 size += v[1](self, True, buf, off + size,
132 buf[off:off + l] = bytearray(kwargs[k])
137 v[1].pack_into(buf, off + size, i)
141 size = v(self, True, buf, off, kwargs[k])
143 v.pack_into(buf, off, kwargs[k])
148 return off + size - offset
151 def __getitem__(self, name):
152 if name in self.messages:
153 return self.messages[name]
156 def encode(self, msgdef, kwargs):
157 # Make suitably large buffer
158 buf = bytearray(self.buffersize)
160 size = self.__struct_type(True, msgdef, buf, offset, kwargs)
161 return buf[:offset + size]
163 def decode(self, msgdef, buf):
164 return self.__struct_type(False, msgdef, buf, 0, None)[1]
166 def __struct_type_decode(self, msgdef, buf, offset):
170 for k,v in msgdef['args'].iteritems():
174 if callable(v[1]): # compound type
176 if v[0] in msgdef['args']: # vla
182 (s,l) = v[1](self, False, buf, off + size, None)
189 res.append(buf[off:off + size])
198 lst.append(v[1].unpack_from(buf, off + size)[0])
202 (s,l) = v(self, False, buf, off, None)
206 res.append(v.unpack_from(buf, off)[0])
209 return off + size - offset, msgdef['return_tuple']._make(res)
211 def ret_tup(self, name):
212 if name in self.messages and 'return_tuple' in self.messages[name]:
213 return self.messages[name]['return_tuple']
216 def add_message(self, name, msgdef):
217 if name in self.messages:
218 raise ValueError('Duplicate message name: ' + name)
220 args = collections.OrderedDict()
224 if type(f) is dict and 'crc' in f:
225 msg['crc'] = f['crc']
228 args[field_name] = self.__struct(*f)
229 fields.append(field_name)
230 msg['return_tuple'] = collections.namedtuple(name, fields,
232 self.messages[name] = msg
233 self.messages[name]['args'] = args
234 return self.messages[name]
236 def add_type(self, name, typedef):
237 self.add_message('vl_api_' + name + '_t', typedef)
239 def make_function(self, i, msgdef, multipart):
240 return lambda **kwargs: (self._call_vpp(i, msgdef, multipart, **kwargs))
242 def _register_functions(self):
243 self.id_names = [None] * (self.vpp_dictionary_maxid + 1)
244 self.id_msgdef = [None] * (self.vpp_dictionary_maxid + 1)
245 for name, msgdef in self.messages.iteritems():
246 if name in self.vpp_dictionary:
247 if self.messages[name]['crc'] != self.vpp_dictionary[name]['crc']:
248 raise ValueError(3, 'Failed CRC checksum ' + name +
249 ' ' + self.messages[name]['crc'] +
250 ' ' + self.vpp_dictionary[name]['crc'])
251 i = self.vpp_dictionary[name]['id']
252 self.id_msgdef[i] = msgdef
253 self.id_names[i] = name
254 multipart = True if name.find('_dump') > 0 else False
255 setattr(self, name, self.make_function(i, msgdef, multipart))
257 def _write (self, buf):
258 if not self.connected:
259 raise IOError(1, 'Not connected')
260 return vpp_api.write(str(buf))
262 def _load_dictionary(self):
263 self.vpp_dictionary = {}
264 self.vpp_dictionary_maxid = 0
266 d = vpp_api.msg_table()
269 raise IOError(3, 'Cannot get VPP API dictionary')
271 name, crc = n.rsplit('_', 1)
273 self.vpp_dictionary[name] = { 'id' : i, 'crc' : crc }
274 self.vpp_dictionary_maxid = max(self.vpp_dictionary_maxid, i)
276 def connect(self, name, chroot_prefix = None):
277 if not chroot_prefix:
278 rv = vpp_api.connect(name, self.msg_handler)
280 rv = vpp_api.connect(name, self.msg_handler, chroot_prefix)
283 raise IOError(2, 'Connect failed')
285 self._load_dictionary()
286 self._register_functions()
288 # Initialise control ping
289 self.control_ping_index = self.vpp_dictionary['control_ping']['id']
290 self.control_ping_msgdef = self.messages['control_ping']
292 self.connected = True
294 def disconnect(self):
295 rv = vpp_api.disconnect()
298 def results_wait(self, context):
299 return (self.results[context]['e'].wait(self.timeout))
301 def results_prepare(self, context):
302 self.results[context] = {}
303 self.results[context]['e'] = threading.Event()
304 self.results[context]['e'].clear()
305 self.results[context]['r'] = []
307 def results_clean(self, context):
308 del self.results[context]
310 def msg_handler(self, msg):
312 eprint('vpp_api.read failed')
315 i, ci = self.header.unpack_from(msg, 0)
316 if self.id_names[i] == 'rx_thread_exit':
320 # Decode message and returns a tuple.
322 msgdef = self.id_msgdef[i]
324 raise IOError(2, 'Reply message undefined')
326 r = self.decode(msgdef, msg)
327 if 'context' in r._asdict():
331 msgname = type(r).__name__
334 # XXX: Call provided callback for event
335 # Are we guaranteed to not get an event during processing of other messages?
336 # How to differentiate what's a callback message and what not? Context = 0?
338 #if not is_waiting_for_reply():
339 if r.context == 0 and self.event_callback:
340 self.event_callback(msgname, r)
344 # Collect results until control ping
346 if msgname == 'control_ping_reply':
347 self.results[context]['e'].set()
350 if not context in self.results:
351 eprint('Not expecting results for this context', context)
354 if 'm' in self.results[context]:
355 self.results[context]['r'].append(r)
358 self.results[context]['r'] = r
359 self.results[context]['e'].set()
361 def _control_ping(self, context):
362 self._write(self.encode(self.control_ping_msgdef,
363 { '_vl_msg_id' : self.control_ping_index,
364 'context' : context}))
366 def _call_vpp(self, i, msgdef, multipart, **kwargs):
367 if not 'context' in kwargs:
368 context = self.get_context()
369 kwargs['context'] = context
371 context = kwargs['context']
372 kwargs['_vl_msg_id'] = i
373 b = self.encode(msgdef, kwargs)
375 self.results_prepare(context)
378 self.results[context]['m'] = True
379 self._control_ping(context)
383 self.results_wait(context)
384 r = self.results[context]['r']
385 self.results_clean(context)
388 def register_event_callback(self, callback):
389 self.event_callback = callback