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):
115 if k not in msgdef['args']:
116 raise ValueError(1, 'Invalid field-name in message call ' + k)
118 for k,v in msgdef['args'].iteritems():
129 size += v[1](self, True, buf, off + size,
137 buf[off:off + l] = bytearray(kwargs[k])
142 v[1].pack_into(buf, off + size, i)
146 size = v(self, True, buf, off, kwargs[k])
148 v.pack_into(buf, off, kwargs[k])
151 size = v.size if not type(v) is list else 0
153 return off + size - offset
156 def __getitem__(self, name):
157 if name in self.messages:
158 return self.messages[name]
161 def encode(self, msgdef, kwargs):
162 # Make suitably large buffer
163 buf = bytearray(self.buffersize)
165 size = self.__struct_type(True, msgdef, buf, offset, kwargs)
166 return buf[:offset + size]
168 def decode(self, msgdef, buf):
169 return self.__struct_type(False, msgdef, buf, 0, None)[1]
171 def __struct_type_decode(self, msgdef, buf, offset):
175 for k,v in msgdef['args'].iteritems():
179 if callable(v[1]): # compound type
181 if v[0] in msgdef['args']: # vla
187 (s,l) = v[1](self, False, buf, off + size, None)
194 res.append(buf[off:off + size])
203 lst.append(v[1].unpack_from(buf, off + size)[0])
207 (s,l) = v(self, False, buf, off, None)
211 res.append(v.unpack_from(buf, off)[0])
214 return off + size - offset, msgdef['return_tuple']._make(res)
216 def ret_tup(self, name):
217 if name in self.messages and 'return_tuple' in self.messages[name]:
218 return self.messages[name]['return_tuple']
221 def add_message(self, name, msgdef):
222 if name in self.messages:
223 raise ValueError('Duplicate message name: ' + name)
225 args = collections.OrderedDict()
229 if type(f) is dict and 'crc' in f:
230 msg['crc'] = f['crc']
233 args[field_name] = self.__struct(*f)
234 fields.append(field_name)
235 msg['return_tuple'] = collections.namedtuple(name, fields,
237 self.messages[name] = msg
238 self.messages[name]['args'] = args
239 return self.messages[name]
241 def add_type(self, name, typedef):
242 self.add_message('vl_api_' + name + '_t', typedef)
244 def make_function(self, i, msgdef, multipart, async):
246 return lambda **kwargs: (self._call_vpp_async(i, msgdef, multipart, **kwargs))
248 return lambda **kwargs: (self._call_vpp(i, msgdef, multipart, **kwargs))
250 def _register_functions(self, async=False):
251 self.id_names = [None] * (self.vpp_dictionary_maxid + 1)
252 self.id_msgdef = [None] * (self.vpp_dictionary_maxid + 1)
253 for name, msgdef in self.messages.iteritems():
254 if name in self.vpp_dictionary:
255 if self.messages[name]['crc'] != self.vpp_dictionary[name]['crc']:
256 raise ValueError(3, 'Failed CRC checksum ' + name +
257 ' ' + self.messages[name]['crc'] +
258 ' ' + self.vpp_dictionary[name]['crc'])
259 i = self.vpp_dictionary[name]['id']
260 self.id_msgdef[i] = msgdef
261 self.id_names[i] = name
262 multipart = True if name.find('_dump') > 0 else False
263 setattr(self, name, self.make_function(i, msgdef, multipart, async))
265 def _write (self, buf):
266 if not self.connected:
267 raise IOError(1, 'Not connected')
268 return vpp_api.write(str(buf))
270 def _load_dictionary(self):
271 self.vpp_dictionary = {}
272 self.vpp_dictionary_maxid = 0
273 d = vpp_api.msg_table()
276 raise IOError(3, 'Cannot get VPP API dictionary')
278 name, crc = n.rsplit('_', 1)
280 self.vpp_dictionary[name] = { 'id' : i, 'crc' : crc }
281 self.vpp_dictionary_maxid = max(self.vpp_dictionary_maxid, i)
283 def connect(self, name, chroot_prefix = None, async = False):
284 msg_handler = self.msg_handler if not async else self.msg_handler_async
285 if not chroot_prefix:
286 rv = vpp_api.connect(name, msg_handler)
288 rv = vpp_api.connect(name, msg_handler, chroot_prefix)
291 raise IOError(2, 'Connect failed')
292 self.connected = True
294 self._load_dictionary()
295 self._register_functions(async=async)
297 # Initialise control ping
298 self.control_ping_index = self.vpp_dictionary['control_ping']['id']
299 self.control_ping_msgdef = self.messages['control_ping']
301 def disconnect(self):
302 rv = vpp_api.disconnect()
305 def results_wait(self, context):
306 return (self.results[context]['e'].wait(self.timeout))
308 def results_prepare(self, context):
309 self.results[context] = {}
310 self.results[context]['e'] = threading.Event()
311 self.results[context]['e'].clear()
312 self.results[context]['r'] = []
314 def results_clean(self, context):
315 del self.results[context]
317 def msg_handler(self, msg):
319 eprint('vpp_api.read failed')
322 i, ci = self.header.unpack_from(msg, 0)
323 if self.id_names[i] == 'rx_thread_exit':
327 # Decode message and returns a tuple.
329 msgdef = self.id_msgdef[i]
331 raise IOError(2, 'Reply message undefined')
333 r = self.decode(msgdef, msg)
334 if 'context' in r._asdict():
338 msgname = type(r).__name__
341 # XXX: Call provided callback for event
342 # Are we guaranteed to not get an event during processing of other messages?
343 # How to differentiate what's a callback message and what not? Context = 0?
345 #if not is_waiting_for_reply():
346 if r.context == 0 and self.event_callback:
347 self.event_callback(msgname, r)
351 # Collect results until control ping
353 if msgname == 'control_ping_reply':
354 self.results[context]['e'].set()
357 if not context in self.results:
358 eprint('Not expecting results for this context', context, r)
361 if 'm' in self.results[context]:
362 self.results[context]['r'].append(r)
365 self.results[context]['r'] = r
366 self.results[context]['e'].set()
368 def msg_handler_async(self, msg):
370 eprint('vpp_api.read failed')
373 i, ci = self.header.unpack_from(msg, 0)
374 if self.id_names[i] == 'rx_thread_exit':
378 # Decode message and returns a tuple.
380 msgdef = self.id_msgdef[i]
382 raise IOError(2, 'Reply message undefined')
384 r = self.decode(msgdef, msg)
385 msgname = type(r).__name__
387 self.event_callback(msgname, r)
389 def _control_ping(self, context):
390 self._write(self.encode(self.control_ping_msgdef,
391 { '_vl_msg_id' : self.control_ping_index,
392 'context' : context}))
394 def _call_vpp(self, i, msgdef, multipart, **kwargs):
395 if not 'context' in kwargs:
396 context = self.get_context()
397 kwargs['context'] = context
399 context = kwargs['context']
400 kwargs['_vl_msg_id'] = i
401 b = self.encode(msgdef, kwargs)
403 self.results_prepare(context)
407 self.results[context]['m'] = True
408 self._control_ping(context)
409 self.results_wait(context)
410 r = self.results[context]['r']
411 self.results_clean(context)
414 def _call_vpp_async(self, i, msgdef, multipart, **kwargs):
415 if not 'context' in kwargs:
416 context = self.get_context()
417 kwargs['context'] = context
419 context = kwargs['context']
420 kwargs['_vl_msg_id'] = i
421 b = self.encode(msgdef, kwargs)
425 def register_event_callback(self, callback):
426 self.event_callback = callback