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):
42 obj, (data2, pos) = self.read((data, 0))
52 f = self.write(None, obj)
62 def unpack(self, data):
63 obj = self._unpack(data)
66 if self._pack(obj) != data:
67 raise AssertionError()
72 data = self._pack(obj)
75 if self._unpack(data) != obj:
76 raise AssertionError((self._unpack(data), obj))
80 def packed_size(self, obj):
81 if hasattr(obj, '_packed_size') and obj._packed_size is not None:
82 type_obj, packed_size = obj._packed_size
86 packed_size = len(self.pack(obj))
88 if hasattr(obj, '_packed_size'):
89 obj._packed_size = self, packed_size
93 class VarIntType(Type):
95 data, file = read(file, 1)
100 desc, length, minimum = '<H', 2, 0xfd
102 desc, length, minimum = '<I', 4, 2**16
104 desc, length, minimum = '<Q', 8, 2**32
106 raise AssertionError()
107 data2, file = read(file, length)
108 res, = struct.unpack(desc, data2)
110 raise AssertionError('VarInt not canonically packed')
113 def write(self, file, item):
115 return file, struct.pack('<B', item)
117 return file, struct.pack('<BH', 0xfd, item)
118 elif item <= 0xffffffff:
119 return file, struct.pack('<BI', 0xfe, item)
120 elif item <= 0xffffffffffffffff:
121 return file, struct.pack('<BQ', 0xff, item)
123 raise ValueError('int too large for varint')
125 class VarStrType(Type):
126 _inner_size = VarIntType()
128 def read(self, file):
129 length, file = self._inner_size.read(file)
130 return read(file, length)
132 def write(self, file, item):
133 return self._inner_size.write(file, len(item)), item
135 class EnumType(Type):
136 def __init__(self, inner, pack_to_unpack):
138 self.pack_to_unpack = pack_to_unpack
140 self.unpack_to_pack = {}
141 for k, v in pack_to_unpack.iteritems():
142 if v in self.unpack_to_pack:
143 raise ValueError('duplicate value in pack_to_unpack')
144 self.unpack_to_pack[v] = k
146 def read(self, file):
147 data, file = self.inner.read(file)
148 if data not in self.pack_to_unpack:
149 raise ValueError('enum data (%r) not in pack_to_unpack (%r)' % (data, self.pack_to_unpack))
150 return self.pack_to_unpack[data], file
152 def write(self, file, item):
153 if item not in self.unpack_to_pack:
154 raise ValueError('enum item (%r) not in unpack_to_pack (%r)' % (item, self.unpack_to_pack))
155 return self.inner.write(file, self.unpack_to_pack[item])
157 class ListType(Type):
158 _inner_size = VarIntType()
160 def __init__(self, type):
163 def read(self, file):
164 length, file = self._inner_size.read(file)
166 for i in xrange(length):
167 res[i], file = self.type.read(file)
170 def write(self, file, item):
171 file = self._inner_size.write(file, len(item))
173 file = self.type.write(file, subitem)
176 class StructType(Type):
177 __slots__ = 'desc length'.split(' ')
179 def __init__(self, desc):
181 self.length = struct.calcsize(self.desc)
183 def read(self, file):
184 data, file = read(file, self.length)
185 return struct.unpack(self.desc, data)[0], file
187 def write(self, file, item):
188 return file, struct.pack(self.desc, item)
190 @memoize.fast_memoize_multiple_args
192 __slots__ = 'bytes step format_str max'.split(' ')
194 def __new__(cls, bits, endianness='little'):
196 assert endianness in ['little', 'big']
197 if bits in [8, 16, 32, 64]:
198 return StructType(('<' if endianness == 'little' else '>') + {8: 'B', 16: 'H', 32: 'I', 64: 'Q'}[bits])
200 return Type.__new__(cls, bits, endianness)
202 def __init__(self, bits, endianness='little'):
204 assert endianness in ['little', 'big']
206 self.step = -1 if endianness == 'little' else 1
207 self.format_str = '%%0%ix' % (2*self.bytes)
210 def read(self, file, b2a_hex=binascii.b2a_hex):
213 data, file = read(file, self.bytes)
214 return int(b2a_hex(data[::self.step]), 16), file
216 def write(self, file, item, a2b_hex=binascii.a2b_hex):
219 if not 0 <= item < self.max:
220 raise ValueError('invalid int value - %r' % (item,))
221 return file, a2b_hex(self.format_str % (item,))[::self.step]
223 class IPV6AddressType(Type):
224 def read(self, file):
225 data, file = read(file, 16)
226 if data[:12] == '00000000000000000000ffff'.decode('hex'):
227 return '.'.join(str(ord(x)) for x in data[12:]), file
228 return ':'.join(data[i*2:(i+1)*2].encode('hex') for i in xrange(8)), file
230 def write(self, file, item):
232 data = ''.join(item.replace(':', '')).decode('hex')
234 bits = map(int, item.split('.'))
236 raise ValueError('invalid address: %r' % (bits,))
237 data = '00000000000000000000ffff'.decode('hex') + ''.join(chr(x) for x in bits)
238 assert len(data) == 16, len(data)
243 def get_record(fields):
244 fields = tuple(sorted(fields))
245 if 'keys' in fields or '_packed_size' in fields:
247 if fields not in _record_types:
248 class _Record(object):
249 __slots__ = fields + ('_packed_size',)
251 self._packed_size = None
253 return repr(dict(self))
254 def __getitem__(self, key):
255 return getattr(self, key)
256 def __setitem__(self, key, value):
257 setattr(self, key, value)
259 # for field in fields:
260 # yield field, getattr(self, field)
263 def get(self, key, default=None):
264 return getattr(self, key, default)
265 def __eq__(self, other):
266 if isinstance(other, dict):
267 return dict(self) == other
268 elif isinstance(other, _Record):
270 if getattr(self, k) != getattr(other, k):
276 def __ne__(self, other):
277 return not (self == other)
278 _record_types[fields] = _Record
279 return _record_types[fields]
281 class ComposedType(Type):
282 def __init__(self, fields):
283 self.fields = list(fields)
284 self.field_names = set(k for k, v in fields)
285 self.record_type = get_record(k for k, v in self.fields)
287 def read(self, file):
288 item = self.record_type()
289 for key, type_ in self.fields:
290 item[key], file = type_.read(file)
293 def write(self, file, item):
294 assert set(item.keys()) == self.field_names, (set(item.keys()) - self.field_names, self.field_names - set(item.keys()))
295 for key, type_ in self.fields:
296 file = type_.write(file, item[key])
299 class PossiblyNoneType(Type):
300 def __init__(self, none_value, inner):
301 self.none_value = none_value
304 def read(self, file):
305 value, file = self.inner.read(file)
306 return None if value == self.none_value else value, file
308 def write(self, file, item):
309 if item == self.none_value:
310 raise ValueError('none_value used')
311 return self.inner.write(file, self.none_value if item is None else item)
313 class FixedStrType(Type):
314 def __init__(self, length):
317 def read(self, file):
318 return read(file, self.length)
320 def write(self, file, item):
321 if len(item) != self.length:
322 raise ValueError('incorrect length item!')