5 from p2pool.util import memoize
7 class EarlyEnd(Exception):
10 class LateEnd(Exception):
13 def read((data, pos), length):
14 data2 = data[pos:pos + length]
15 if len(data2) != length:
17 return data2, (data, pos + length)
19 def size((data, pos)):
20 return len(data) - pos
26 rval = getattr(self, '_hash', None)
29 rval = self._hash = hash((type(self), frozenset(self.__dict__.items())))
35 def __eq__(self, other):
36 return type(other) is type(self) and other.__dict__ == self.__dict__
38 def __ne__(self, other):
39 return not (self == other)
41 def _unpack(self, data, ignore_trailing=False):
42 obj, (data2, pos) = self.read((data, 0))
46 if pos != len(data) and not ignore_trailing:
52 f = self.write(None, obj)
62 def unpack(self, data, ignore_trailing=False):
63 obj = self._unpack(data, ignore_trailing)
66 packed = self._pack(obj)
67 good = data.startswith(packed) if ignore_trailing else data == packed
69 raise AssertionError()
74 data = self._pack(obj)
77 if self._unpack(data) != obj:
78 raise AssertionError((self._unpack(data), obj))
82 def packed_size(self, obj):
83 if hasattr(obj, '_packed_size') and obj._packed_size is not None:
84 type_obj, packed_size = obj._packed_size
88 packed_size = len(self.pack(obj))
90 if hasattr(obj, '_packed_size'):
91 obj._packed_size = self, packed_size
95 class VarIntType(Type):
97 data, file = read(file, 1)
102 desc, length, minimum = '<H', 2, 0xfd
104 desc, length, minimum = '<I', 4, 2**16
106 desc, length, minimum = '<Q', 8, 2**32
108 raise AssertionError()
109 data2, file = read(file, length)
110 res, = struct.unpack(desc, data2)
112 raise AssertionError('VarInt not canonically packed')
115 def write(self, file, item):
117 return file, struct.pack('<B', item)
119 return file, struct.pack('<BH', 0xfd, item)
120 elif item <= 0xffffffff:
121 return file, struct.pack('<BI', 0xfe, item)
122 elif item <= 0xffffffffffffffff:
123 return file, struct.pack('<BQ', 0xff, item)
125 raise ValueError('int too large for varint')
127 class VarStrType(Type):
128 _inner_size = VarIntType()
130 def read(self, file):
131 length, file = self._inner_size.read(file)
132 return read(file, length)
134 def write(self, file, item):
135 return self._inner_size.write(file, len(item)), item
137 class EnumType(Type):
138 def __init__(self, inner, pack_to_unpack):
140 self.pack_to_unpack = pack_to_unpack
142 self.unpack_to_pack = {}
143 for k, v in pack_to_unpack.iteritems():
144 if v in self.unpack_to_pack:
145 raise ValueError('duplicate value in pack_to_unpack')
146 self.unpack_to_pack[v] = k
148 def read(self, file):
149 data, file = self.inner.read(file)
150 if data not in self.pack_to_unpack:
151 raise ValueError('enum data (%r) not in pack_to_unpack (%r)' % (data, self.pack_to_unpack))
152 return self.pack_to_unpack[data], file
154 def write(self, file, item):
155 if item not in self.unpack_to_pack:
156 raise ValueError('enum item (%r) not in unpack_to_pack (%r)' % (item, self.unpack_to_pack))
157 return self.inner.write(file, self.unpack_to_pack[item])
159 class ListType(Type):
160 _inner_size = VarIntType()
162 def __init__(self, type, mul=1):
166 def read(self, file):
167 length, file = self._inner_size.read(file)
170 for i in xrange(length):
171 res[i], file = self.type.read(file)
174 def write(self, file, item):
175 assert len(item) % self.mul == 0
176 file = self._inner_size.write(file, len(item)//self.mul)
178 file = self.type.write(file, subitem)
181 class StructType(Type):
182 __slots__ = 'desc length'.split(' ')
184 def __init__(self, desc):
186 self.length = struct.calcsize(self.desc)
188 def read(self, file):
189 data, file = read(file, self.length)
190 return struct.unpack(self.desc, data)[0], file
192 def write(self, file, item):
193 return file, struct.pack(self.desc, item)
195 @memoize.fast_memoize_multiple_args
197 __slots__ = 'bytes step format_str max'.split(' ')
199 def __new__(cls, bits, endianness='little'):
201 assert endianness in ['little', 'big']
202 if bits in [8, 16, 32, 64]:
203 return StructType(('<' if endianness == 'little' else '>') + {8: 'B', 16: 'H', 32: 'I', 64: 'Q'}[bits])
205 return Type.__new__(cls, bits, endianness)
207 def __init__(self, bits, endianness='little'):
209 assert endianness in ['little', 'big']
211 self.step = -1 if endianness == 'little' else 1
212 self.format_str = '%%0%ix' % (2*self.bytes)
215 def read(self, file, b2a_hex=binascii.b2a_hex):
218 data, file = read(file, self.bytes)
219 return int(b2a_hex(data[::self.step]), 16), file
221 def write(self, file, item, a2b_hex=binascii.a2b_hex):
224 if not 0 <= item < self.max:
225 raise ValueError('invalid int value - %r' % (item,))
226 return file, a2b_hex(self.format_str % (item,))[::self.step]
228 class IPV6AddressType(Type):
229 def read(self, file):
230 data, file = read(file, 16)
231 if data[:12] == '00000000000000000000ffff'.decode('hex'):
232 return '.'.join(str(ord(x)) for x in data[12:]), file
233 return ':'.join(data[i*2:(i+1)*2].encode('hex') for i in xrange(8)), file
235 def write(self, file, item):
237 data = ''.join(item.replace(':', '')).decode('hex')
239 bits = map(int, item.split('.'))
241 raise ValueError('invalid address: %r' % (bits,))
242 data = '00000000000000000000ffff'.decode('hex') + ''.join(chr(x) for x in bits)
243 assert len(data) == 16, len(data)
248 def get_record(fields):
249 fields = tuple(sorted(fields))
250 if 'keys' in fields or '_packed_size' in fields:
252 if fields not in _record_types:
253 class _Record(object):
254 __slots__ = fields + ('_packed_size',)
256 self._packed_size = None
258 return repr(dict(self))
259 def __getitem__(self, key):
260 return getattr(self, key)
261 def __setitem__(self, key, value):
262 setattr(self, key, value)
264 # for field in fields:
265 # yield field, getattr(self, field)
268 def get(self, key, default=None):
269 return getattr(self, key, default)
270 def __eq__(self, other):
271 if isinstance(other, dict):
272 return dict(self) == other
273 elif isinstance(other, _Record):
275 if getattr(self, k) != getattr(other, k):
281 def __ne__(self, other):
282 return not (self == other)
283 _record_types[fields] = _Record
284 return _record_types[fields]
286 class ComposedType(Type):
287 def __init__(self, fields):
288 self.fields = list(fields)
289 self.field_names = set(k for k, v in fields)
290 self.record_type = get_record(k for k, v in self.fields)
292 def read(self, file):
293 item = self.record_type()
294 for key, type_ in self.fields:
295 item[key], file = type_.read(file)
298 def write(self, file, item):
299 assert set(item.keys()) == self.field_names, (set(item.keys()) - self.field_names, self.field_names - set(item.keys()))
300 for key, type_ in self.fields:
301 file = type_.write(file, item[key])
304 class PossiblyNoneType(Type):
305 def __init__(self, none_value, inner):
306 self.none_value = none_value
309 def read(self, file):
310 value, file = self.inner.read(file)
311 return None if value == self.none_value else value, file
313 def write(self, file, item):
314 if item == self.none_value:
315 raise ValueError('none_value used')
316 return self.inner.write(file, self.none_value if item is None else item)
318 class FixedStrType(Type):
319 def __init__(self, length):
322 def read(self, file):
323 return read(file, self.length)
325 def write(self, file, item):
326 if len(item) != self.length:
327 raise ValueError('incorrect length item!')