2 # Copyright (c) 2018 Cisco and/or its affiliates.
3 # Licensed under the Apache License, Version 2.0 (the "License");
4 # you may not use this file except in compliance with the License.
5 # You may obtain a copy of the License at:
7 # http://www.apache.org/licenses/LICENSE-2.0
9 # Unless required by applicable law or agreed to in writing, software
10 # distributed under the License is distributed on an "AS IS" BASIS,
11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 # See the License for the specific language governing permissions and
13 # limitations under the License.
18 from enum import IntEnum
20 from .vpp_format import VPPFormat
23 # Set log-level in application by doing e.g.:
24 # logger = logging.getLogger('vpp_serializer')
25 # logger.setLevel(logging.DEBUG)
27 logger = logging.getLogger(__name__)
30 class BaseTypes(object):
31 def __init__(self, type, elements=0):
32 base_types = {'u8': '>B',
41 if elements > 0 and type == 'u8':
42 self.packer = struct.Struct('>%ss' % elements)
44 self.packer = struct.Struct(base_types[type])
45 self.size = self.packer.size
46 logger.debug('Adding {} with format: {}'
47 .format(type, base_types[type]))
49 def pack(self, data, kwargs=None):
50 if not data: # Default to zero if not specified
52 return self.packer.pack(data)
54 def unpack(self, data, offset, result=None):
55 return self.packer.unpack_from(data, offset)[0], self.packer.size
59 types['u8'] = BaseTypes('u8')
60 types['u16'] = BaseTypes('u16')
61 types['u32'] = BaseTypes('u32')
62 types['i32'] = BaseTypes('i32')
63 types['u64'] = BaseTypes('u64')
64 types['f64'] = BaseTypes('f64')
65 types['bool'] = BaseTypes('bool')
68 def vpp_get_type(name):
75 class FixedList_u8(object):
76 def __init__(self, name, field_type, num):
79 self.packer = BaseTypes(field_type, num)
80 self.size = self.packer.size
82 def pack(self, list, kwargs = None):
83 """Packs a fixed length bytestring. Left-pads with zeros
84 if input data is too short."""
86 return b'\x00' * self.size
87 if len(list) > self.num:
88 raise ValueError('Fixed list length error for "{}", got: {}'
90 .format(self.name, len(list), self.num))
91 return self.packer.pack(list)
93 def unpack(self, data, offset=0, result=None):
94 if len(data[offset:]) < self.num:
95 raise ValueError('Invalid array length for "{}" got {}'
97 .format(self.name, len(data[offset:]), self.num))
98 return self.packer.unpack(data, offset)
101 class FixedList(object):
102 def __init__(self, name, field_type, num):
104 self.packer = types[field_type]
105 self.size = self.packer.size * num
107 def pack(self, list, kwargs):
108 if len(list) != self.num:
109 raise ValueError('Fixed list length error, got: {} expected: {}'
110 .format(len(list), self.num))
113 b += self.packer.pack(e)
116 def unpack(self, data, offset=0, result=None):
117 # Return a list of arguments
120 for e in range(self.num):
121 x, size = self.packer.unpack(data, offset)
128 class VLAList(object):
129 def __init__(self, name, field_type, len_field_name, index):
132 self.packer = types[field_type]
133 self.size = self.packer.size
134 self.length_field = len_field_name
136 def pack(self, list, kwargs=None):
139 if len(list) != kwargs[self.length_field]:
140 raise ValueError('Variable length error, got: {} expected: {}'
141 .format(len(list), kwargs[self.length_field]))
145 if self.packer.size == 1:
146 return bytearray(list)
149 b += self.packer.pack(e)
152 def unpack(self, data, offset=0, result=None):
153 # Return a list of arguments
157 if self.packer.size == 1:
158 if result[self.index] == 0:
160 p = BaseTypes('u8', result[self.index])
161 return p.unpack(data, offset)
164 for e in range(result[self.index]):
165 x, size = self.packer.unpack(data, offset)
172 class VLAList_legacy():
173 def __init__(self, name, field_type):
174 self.packer = types[field_type]
175 self.size = self.packer.size
177 def pack(self, list, kwargs=None):
178 if self.packer.size == 1:
183 b += self.packer.pack(e)
186 def unpack(self, data, offset=0, result=None):
188 # Return a list of arguments
189 if (len(data) - offset) % self.packer.size:
190 raise ValueError('Legacy Variable Length Array length mismatch.')
191 elements = int((len(data) - offset) / self.packer.size)
193 for e in range(elements):
194 x, size = self.packer.unpack(data, offset)
196 offset += self.packer.size
201 class VPPEnumType(object):
202 def __init__(self, name, msgdef):
203 self.size = types['u32'].size
206 if type(f) is dict and 'enumtype' in f:
207 if f['enumtype'] != 'u32':
208 raise NotImplementedError
211 e_hash[ename] = evalue
212 self.enum = IntEnum(name, e_hash)
214 logger.debug('Adding enum {}'.format(name))
216 def __getattr__(self, name):
217 return self.enum[name]
219 def __nonzero__(self):
222 def pack(self, data, kwargs=None):
223 return types['u32'].pack(data)
225 def unpack(self, data, offset=0, result=None):
226 x, size = types['u32'].unpack(data, offset)
227 return self.enum(x), size
230 class VPPUnionType(object):
231 def __init__(self, name, msgdef):
236 self.packers = collections.OrderedDict()
237 for i, f in enumerate(msgdef):
238 if type(f) is dict and 'crc' in f:
242 if f_type not in types:
243 logger.debug('Unknown union type {}'.format(f_type))
244 raise ValueError('Unknown message type {}'.format(f_type))
245 fields.append(f_name)
246 size = types[f_type].size
247 self.packers[f_name] = types[f_type]
253 self.tuple = collections.namedtuple(name, fields, rename=True)
254 logger.debug('Adding union {}'.format(name))
256 # Union of variable length?
257 def pack(self, data, kwargs=None):
259 return b'\x00' * self.size
261 for k, v in data.items():
262 logger.debug("Key: {} Value: {}".format(k, v))
263 b = self.packers[k].pack(v, kwargs)
265 r = bytearray(self.size)
269 def unpack(self, data, offset=0, result=None):
272 for k, p in self.packers.items():
273 x, size = p.unpack(data, offset)
277 return self.tuple._make(r), maxsize
280 def VPPTypeAlias(name, msgdef):
281 t = vpp_get_type(msgdef['type'])
284 if 'length' in msgdef:
285 if msgdef['length'] == 0:
287 types[name] = FixedList(name, msgdef['type'], msgdef['length'])
292 class VPPType(object):
293 # Set everything up to be able to pack / unpack
294 def __init__(self, name, msgdef):
300 self.field_by_name = {}
302 for i, f in enumerate(msgdef):
303 if type(f) is dict and 'crc' in f:
306 f_type, f_name = f[:2]
307 self.fields.append(f_name)
308 self.field_by_name[f_name] = None
309 self.fieldtypes.append(f_type)
310 if f_type not in types:
311 logger.debug('Unknown type {}'.format(f_type))
312 raise ValueError('Unknown message type {}'.format(f_type))
313 if len(f) == 3: # list
315 if list_elements == 0:
316 p = VLAList_legacy(f_name, f_type)
317 self.packers.append(p)
319 p = FixedList_u8(f_name, f_type, list_elements)
320 self.packers.append(p)
323 p = FixedList(f_name, f_type, list_elements)
324 self.packers.append(p)
326 elif len(f) == 4: # Variable length list
327 # Find index of length field
328 length_index = self.fields.index(f[3])
329 p = VLAList(f_name, f_type, f[3], length_index)
330 self.packers.append(p)
332 self.packers.append(types[f_type])
333 size += types[f_type].size
336 self.tuple = collections.namedtuple(name, self.fields, rename=True)
338 logger.debug('Adding type {}'.format(name))
340 def pack(self, data, kwargs=None):
344 for i, a in enumerate(self.fields):
346 # Try one of the format functions
347 if data and type(data) is not dict and a not in data:
348 raise ValueError("Invalid argument: {} expected {}.{}".
349 format(data, self.name, a))
351 # Defaulting to zero.
352 if not data or a not in data: # Default to 0
354 kwarg = None # No default for VLA
357 kwarg = kwargs[a] if a in kwargs else None
359 if isinstance(self.packers[i], VPPType):
361 b += self.packers[i].pack(arg, kwarg)
363 # Invalid argument, can we convert it?
364 arg = VPPFormat.format(self.packers[i].name, data[a])
367 b += self.packers[i].pack(arg, kwarg)
369 b += self.packers[i].pack(arg, kwargs)
373 def unpack(self, data, offset=0, result=None):
374 # Return a list of arguments
377 for p in self.packers:
378 x, size = p.unpack(data, offset, result)
379 if type(x) is tuple and len(x) == 1:
384 t = self.tuple._make(result)
388 class VPPMessage(VPPType):