src/bindings/python/bt2/bt2/value.py

   1 # The MIT License (MIT)
   2 #
   3 # Copyright (c) 2017 Philippe Proulx <pproulx@efficios.com>
   4 #
   5 # Permission is hereby granted, free of charge, to any person obtaining a copy
   6 # of this software and associated documentation files (the "Software"), to deal
   7 # in the Software without restriction, including without limitation the rights
   8 # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   9 # copies of the Software, and to permit persons to whom the Software is
  10 # furnished to do so, subject to the following conditions:
  11 #
  12 # The above copyright notice and this permission notice shall be included in
  13 # all copies or substantial portions of the Software.
  14 #
  15 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  18 # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  21 # THE SOFTWARE.
  22
  23 from bt2 import native_bt, object, utils
  24 import collections.abc
  25 import functools
  26 import numbers
  27 import math
  28 import abc
  29 import bt2
  30
  31
  32 def _handle_status(status, obj_name):
  33     if status >= 0:
  34         return
  35     else:
  36         raise RuntimeError('unexpected error')
  37
  38
  39 def _create_from_ptr(ptr):
  40     if ptr is None or ptr == native_bt.value_null:
  41         return
  42
  43     typeid = native_bt.value_get_type(ptr)
  44     return _TYPE_TO_OBJ[typeid]._create_from_ptr(ptr)
  45
  46
  47 def _create_from_ptr_and_get_ref(ptr):
  48     if ptr is None or ptr == native_bt.value_null:
  49         return
  50
  51     typeid = native_bt.value_get_type(ptr)
  52     return _TYPE_TO_OBJ[typeid]._create_from_ptr_and_get_ref(ptr)
  53
  54
  55 def create_value(value):
  56     if value is None:
  57         # null value object
  58         return
  59
  60     if isinstance(value, _Value):
  61         return value
  62
  63     if isinstance(value, bool):
  64         return BoolValue(value)
  65
  66     if isinstance(value, int):
  67         return SignedIntegerValue(value)
  68
  69     if isinstance(value, float):
  70         return RealValue(value)
  71
  72     if isinstance(value, str):
  73         return StringValue(value)
  74
  75     try:
  76         return MapValue(value)
  77     except:
  78         pass
  79
  80     try:
  81         return ArrayValue(value)
  82     except:
  83         pass
  84
  85     raise TypeError("cannot create value object from '{}' object".format(value.__class__.__name__))
  86
  87
  88 class _Value(object._SharedObject, metaclass=abc.ABCMeta):
  89     _get_ref = staticmethod(native_bt.value_get_ref)
  90     _put_ref = staticmethod(native_bt.value_put_ref)
  91
  92     def __eq__(self, other):
  93         if other is None:
  94             # self is never the null value object
  95             return False
  96
  97         # try type-specific comparison first
  98         spec_eq = self._spec_eq(other)
  99
 100         if spec_eq is not None:
 101             return spec_eq
 102
 103         if not isinstance(other, _Value):
 104             # not comparing apples to apples
 105             return False
 106
 107         # fall back to native comparison function
 108         return native_bt.value_compare(self._ptr, other._ptr)
 109
 110     def __ne__(self, other):
 111         return not (self == other)
 112
 113     @abc.abstractmethod
 114     def _spec_eq(self, other):
 115         pass
 116
 117     def _handle_status(self, status):
 118         _handle_status(status, self._NAME)
 119
 120     def _check_create_status(self, ptr):
 121         if ptr is None:
 122             raise bt2.CreationError(
 123                 'cannot create {} value object'.format(self._NAME.lower()))
 124
 125
 126 @functools.total_ordering
 127 class _NumericValue(_Value):
 128     @staticmethod
 129     def _extract_value(other):
 130         if isinstance(other, _NumericValue):
 131             return other._value
 132
 133         if other is True or other is False:
 134             return other
 135
 136         if isinstance(other, numbers.Integral):
 137             return int(other)
 138
 139         if isinstance(other, numbers.Real):
 140             return float(other)
 141
 142         if isinstance(other, numbers.Complex):
 143             return complex(other)
 144
 145         raise TypeError("'{}' object is not a number object".format(other.__class__.__name__))
 146
 147     def __int__(self):
 148         return int(self._value)
 149
 150     def __float__(self):
 151         return float(self._value)
 152
 153     def __repr__(self):
 154         return repr(self._value)
 155
 156     def __lt__(self, other):
 157         if not isinstance(other, numbers.Number):
 158             raise TypeError('unorderable types: {}() < {}()'.format(self.__class__.__name__,
 159                                                                     other.__class__.__name__))
 160
 161         return self._value < float(other)
 162
 163     def _spec_eq(self, other):
 164         pass
 165
 166     def __eq__(self, other):
 167         if not isinstance(other, numbers.Number):
 168             return False
 169
 170         return self._value == complex(other)
 171
 172     def __rmod__(self, other):
 173         return self._extract_value(other) % self._value
 174
 175     def __mod__(self, other):
 176         return self._value % self._extract_value(other)
 177
 178     def __rfloordiv__(self, other):
 179         return self._extract_value(other) // self._value
 180
 181     def __floordiv__(self, other):
 182         return self._value // self._extract_value(other)
 183
 184     def __round__(self, ndigits=None):
 185         if ndigits is None:
 186             return round(self._value)
 187         else:
 188             return round(self._value, ndigits)
 189
 190     def __ceil__(self):
 191         return math.ceil(self._value)
 192
 193     def __floor__(self):
 194         return math.floor(self._value)
 195
 196     def __trunc__(self):
 197         return int(self._value)
 198
 199     def __abs__(self):
 200         return abs(self._value)
 201
 202     def __add__(self, other):
 203         return self._value + self._extract_value(other)
 204
 205     def __radd__(self, other):
 206         return self.__add__(other)
 207
 208     def __neg__(self):
 209         return -self._value
 210
 211     def __pos__(self):
 212         return +self._value
 213
 214     def __mul__(self, other):
 215         return self._value * self._extract_value(other)
 216
 217     def __rmul__(self, other):
 218         return self.__mul__(other)
 219
 220     def __truediv__(self, other):
 221         return self._value / self._extract_value(other)
 222
 223     def __rtruediv__(self, other):
 224         return self._extract_value(other) / self._value
 225
 226     def __pow__(self, exponent):
 227         return self._value ** self._extract_value(exponent)
 228
 229     def __rpow__(self, base):
 230         return self._extract_value(base) ** self._value
 231
 232     def __iadd__(self, other):
 233         self.value = self + other
 234         return self
 235
 236     def __isub__(self, other):
 237         self.value = self - other
 238         return self
 239
 240     def __imul__(self, other):
 241         self.value = self * other
 242         return self
 243
 244     def __itruediv__(self, other):
 245         self.value = self / other
 246         return self
 247
 248     def __ifloordiv__(self, other):
 249         self.value = self // other
 250         return self
 251
 252     def __imod__(self, other):
 253         self.value = self % other
 254         return self
 255
 256     def __ipow__(self, other):
 257         self.value = self ** other
 258         return self
 259
 260
 261 class _IntegralValue(_NumericValue, numbers.Integral):
 262     def __lshift__(self, other):
 263         return self._value << self._extract_value(other)
 264
 265     def __rlshift__(self, other):
 266         return self._extract_value(other) << self._value
 267
 268     def __rshift__(self, other):
 269         return self._value >> self._extract_value(other)
 270
 271     def __rrshift__(self, other):
 272         return self._extract_value(other) >> self._value
 273
 274     def __and__(self, other):
 275         return self._value & self._extract_value(other)
 276
 277     def __rand__(self, other):
 278         return self._extract_value(other) & self._value
 279
 280     def __xor__(self, other):
 281         return self._value ^ self._extract_value(other)
 282
 283     def __rxor__(self, other):
 284         return self._extract_value(other) ^ self._value
 285
 286     def __or__(self, other):
 287         return self._value | self._extract_value(other)
 288
 289     def __ror__(self, other):
 290         return self._extract_value(other) | self._value
 291
 292     def __invert__(self):
 293         return ~self._value
 294
 295     def __ilshift__(self, other):
 296         self.value = self << other
 297         return self
 298
 299     def __irshift__(self, other):
 300         self.value = self >> other
 301         return self
 302
 303     def __iand__(self, other):
 304         self.value = self & other
 305         return self
 306
 307     def __ixor__(self, other):
 308         self.value = self ^ other
 309         return self
 310
 311     def __ior__(self, other):
 312         self.value = self | other
 313         return self
 314
 315
 316 class _RealValue(_NumericValue, numbers.Real):
 317     pass
 318
 319
 320 class BoolValue(_Value):
 321     _NAME = 'Boolean'
 322
 323     def __init__(self, value=None):
 324         if value is None:
 325             ptr = native_bt.value_bool_create()
 326         else:
 327             ptr = native_bt.value_bool_create_init(self._value_to_bool(value))
 328
 329         self._check_create_status(ptr)
 330         super().__init__(ptr)
 331
 332     def _spec_eq(self, other):
 333         if isinstance(other, numbers.Number):
 334             return self._value == bool(other)
 335
 336     def __bool__(self):
 337         return self._value
 338
 339     def __repr__(self):
 340         return repr(self._value)
 341
 342     def _value_to_bool(self, value):
 343         if isinstance(value, BoolValue):
 344             value = value._value
 345
 346         if not isinstance(value, bool):
 347             raise TypeError("'{}' object is not a 'bool' or 'BoolValue' object".format(value.__class__))
 348
 349         return int(value)
 350
 351     @property
 352     def _value(self):
 353         value = native_bt.value_bool_get(self._ptr)
 354         return value != 0
 355
 356     def _set_value(self, value):
 357         native_bt.value_bool_set(self._ptr, self._value_to_bool(value))
 358
 359     value = property(fset=_set_value)
 360
 361
 362 class _IntegerValue(_IntegralValue):
 363     def __init__(self, value=None):
 364         if value is None:
 365             ptr = self._create_default_value()
 366         else:
 367             ptr = self._create_value(self._value_to_int(value))
 368
 369         self._check_create_status(ptr)
 370         super().__init__(ptr)
 371
 372     def _value_to_int(self, value):
 373         if not isinstance(value, numbers.Real):
 374             raise TypeError('expecting a number object')
 375
 376         value = int(value)
 377         self._check_int_range(value)
 378         return value
 379
 380     @property
 381     def _value(self):
 382         return self._get_value(self._ptr)
 383
 384     def _prop_set_value(self, value):
 385         self._set_value(self._ptr, self._value_to_int(value))
 386
 387     value = property(fset=_prop_set_value)
 388
 389
 390 class UnsignedIntegerValue(_IntegerValue):
 391     _check_int_range = staticmethod(utils._check_uint64)
 392     _create_default_value = staticmethod(native_bt.value_unsigned_integer_create)
 393     _create_value = staticmethod(native_bt.value_unsigned_integer_create_init)
 394     _set_value = staticmethod(native_bt.value_unsigned_integer_set)
 395     _get_value = staticmethod(native_bt.value_unsigned_integer_get)
 396
 397
 398 class SignedIntegerValue(_IntegerValue):
 399     _check_int_range = staticmethod(utils._check_int64)
 400     _create_default_value = staticmethod(native_bt.value_signed_integer_create)
 401     _create_value = staticmethod(native_bt.value_signed_integer_create_init)
 402     _set_value = staticmethod(native_bt.value_signed_integer_set)
 403     _get_value = staticmethod(native_bt.value_signed_integer_get)
 404
 405
 406 class RealValue(_RealValue):
 407     _NAME = 'Real number'
 408
 409     def __init__(self, value=None):
 410         if value is None:
 411             ptr = native_bt.value_real_create()
 412         else:
 413             value = self._value_to_float(value)
 414             ptr = native_bt.value_real_create_init(value)
 415
 416         self._check_create_status(ptr)
 417         super().__init__(ptr)
 418
 419     def _value_to_float(self, value):
 420         if not isinstance(value, numbers.Real):
 421             raise TypeError("expecting a real number object")
 422
 423         return float(value)
 424
 425     @property
 426     def _value(self):
 427         return native_bt.value_real_get(self._ptr)
 428
 429     def _set_value(self, value):
 430         native_bt.value_real_set(self._ptr, self._value_to_float(value))
 431
 432     value = property(fset=_set_value)
 433
 434
 435 @functools.total_ordering
 436 class StringValue(collections.abc.Sequence, _Value):
 437     _NAME = 'String'
 438
 439     def __init__(self, value=None):
 440         if value is None:
 441             ptr = native_bt.value_string_create()
 442         else:
 443             ptr = native_bt.value_string_create_init(self._value_to_str(value))
 444
 445         self._check_create_status(ptr)
 446         super().__init__(ptr)
 447
 448     def _value_to_str(self, value):
 449         if isinstance(value, self.__class__):
 450             value = value._value
 451
 452         utils._check_str(value)
 453         return value
 454
 455     @property
 456     def _value(self):
 457         return native_bt.value_string_get(self._ptr)
 458
 459     def _set_value(self, value):
 460         status = native_bt.value_string_set(self._ptr, self._value_to_str(value))
 461         self._handle_status(status)
 462
 463     value = property(fset=_set_value)
 464
 465     def _spec_eq(self, other):
 466         try:
 467             return self._value == self._value_to_str(other)
 468         except:
 469             return
 470
 471     def __lt__(self, other):
 472         return self._value < self._value_to_str(other)
 473
 474     def __bool__(self):
 475         return bool(self._value)
 476
 477     def __repr__(self):
 478         return repr(self._value)
 479
 480     def __str__(self):
 481         return self._value
 482
 483     def __getitem__(self, index):
 484         return self._value[index]
 485
 486     def __len__(self):
 487         return len(self._value)
 488
 489     def __iadd__(self, value):
 490         curvalue = self._value
 491         curvalue += self._value_to_str(value)
 492         self.value = curvalue
 493         return self
 494
 495
 496 class _Container:
 497     def __bool__(self):
 498         return len(self) != 0
 499
 500     def __delitem__(self, index):
 501         raise NotImplementedError
 502
 503
 504 class ArrayValue(_Container, collections.abc.MutableSequence, _Value):
 505     _NAME = 'Array'
 506
 507     def __init__(self, value=None):
 508         ptr = native_bt.value_array_create()
 509         self._check_create_status(ptr)
 510         super().__init__(ptr)
 511
 512         # Python will raise a TypeError if there's anything wrong with
 513         # the iterable protocol.
 514         if value is not None:
 515             for elem in value:
 516                 self.append(elem)
 517
 518     def _spec_eq(self, other):
 519         try:
 520             if len(self) != len(other):
 521                 # early mismatch
 522                 return False
 523
 524             for self_elem, other_elem in zip(self, other):
 525                 if self_elem != other_elem:
 526                     return False
 527
 528             return True
 529         except:
 530             return
 531
 532     def __len__(self):
 533         size = native_bt.value_array_get_size(self._ptr)
 534         assert(size >= 0)
 535         return size
 536
 537     def _check_index(self, index):
 538         # TODO: support slices also
 539         if not isinstance(index, numbers.Integral):
 540             raise TypeError("'{}' object is not an integral number object: invalid index".format(index.__class__.__name__))
 541
 542         index = int(index)
 543
 544         if index < 0 or index >= len(self):
 545             raise IndexError('array value object index is out of range')
 546
 547     def __getitem__(self, index):
 548         self._check_index(index)
 549         ptr = native_bt.value_array_borrow_element_by_index(self._ptr, index)
 550         assert(ptr)
 551         return _create_from_ptr_and_get_ref(ptr)
 552
 553     def __setitem__(self, index, value):
 554         self._check_index(index)
 555         value = create_value(value)
 556
 557         if value is None:
 558             ptr = native_bt.value_null
 559         else:
 560             ptr = value._ptr
 561
 562         status = native_bt.value_array_set_element_by_index(
 563             self._ptr, index, ptr)
 564         self._handle_status(status)
 565
 566     def append(self, value):
 567         value = create_value(value)
 568
 569         if value is None:
 570             ptr = native_bt.value_null
 571         else:
 572             ptr = value._ptr
 573
 574         status = native_bt.value_array_append_element(self._ptr, ptr)
 575         self._handle_status(status)
 576
 577     def __iadd__(self, iterable):
 578         # Python will raise a TypeError if there's anything wrong with
 579         # the iterable protocol.
 580         for elem in iterable:
 581             self.append(elem)
 582
 583         return self
 584
 585     def __repr__(self):
 586         return '[{}]'.format(', '.join([repr(v) for v in self]))
 587
 588     def insert(self, value):
 589         raise NotImplementedError
 590
 591
 592 class _MapValueKeyIterator(collections.abc.Iterator):
 593     def __init__(self, map_obj):
 594         self._map_obj = map_obj
 595         self._at = 0
 596         keys_ptr = native_bt.value_map_get_keys(map_obj._ptr)
 597
 598         if keys_ptr is None:
 599             raise RuntimeError('unexpected error: cannot get map value object keys')
 600
 601         self._keys = _create_from_ptr(keys_ptr)
 602
 603     def __next__(self):
 604         if self._at == len(self._map_obj):
 605             raise StopIteration
 606
 607         key = self._keys[self._at]
 608         self._at += 1
 609         return str(key)
 610
 611
 612 class MapValue(_Container, collections.abc.MutableMapping, _Value):
 613     _NAME = 'Map'
 614
 615     def __init__(self, value=None):
 616         ptr = native_bt.value_map_create()
 617         self._check_create_status(ptr)
 618         super().__init__(ptr)
 619
 620         # Python will raise a TypeError if there's anything wrong with
 621         # the iterable/mapping protocol.
 622         if value is not None:
 623             for key, elem in value.items():
 624                 self[key] = elem
 625
 626     def __eq__(self, other):
 627         return _Value.__eq__(self, other)
 628
 629     def __ne__(self, other):
 630         return _Value.__ne__(self, other)
 631
 632     def _spec_eq(self, other):
 633         try:
 634             if len(self) != len(other):
 635                 # early mismatch
 636                 return False
 637
 638             for self_key in self:
 639                 if self_key not in other:
 640                     return False
 641
 642                 self_value = self[self_key]
 643                 other_value = other[self_key]
 644
 645                 if self_value != other_value:
 646                     return False
 647
 648             return True
 649         except:
 650             return
 651
 652     def __len__(self):
 653         size = native_bt.value_map_get_size(self._ptr)
 654         assert(size >= 0)
 655         return size
 656
 657     def __contains__(self, key):
 658         self._check_key_type(key)
 659         return native_bt.value_map_has_entry(self._ptr, key)
 660
 661     def _check_key_type(self, key):
 662         utils._check_str(key)
 663
 664     def _check_key(self, key):
 665         if key not in self:
 666             raise KeyError(key)
 667
 668     def __getitem__(self, key):
 669         self._check_key(key)
 670         ptr = native_bt.value_map_borrow_entry_value(self._ptr, key)
 671         assert(ptr)
 672         return _create_from_ptr_and_get_ref(ptr)
 673
 674     def __iter__(self):
 675         return _MapValueKeyIterator(self)
 676
 677     def __setitem__(self, key, value):
 678         self._check_key_type(key)
 679         value = create_value(value)
 680
 681         if value is None:
 682             ptr = native_bt.value_null
 683         else:
 684             ptr = value._ptr
 685
 686         status = native_bt.value_map_insert_entry(self._ptr, key, ptr)
 687         self._handle_status(status)
 688
 689     def __repr__(self):
 690         items = ['{}: {}'.format(repr(k), repr(v)) for k, v in self.items()]
 691         return '{{{}}}'.format(', '.join(items))
 692
 693
 694 _TYPE_TO_OBJ = {
 695     native_bt.VALUE_TYPE_BOOL: BoolValue,
 696     native_bt.VALUE_TYPE_UNSIGNED_INTEGER: UnsignedIntegerValue,
 697     native_bt.VALUE_TYPE_SIGNED_INTEGER: SignedIntegerValue,
 698     native_bt.VALUE_TYPE_REAL: RealValue,
 699     native_bt.VALUE_TYPE_STRING: StringValue,
 700     native_bt.VALUE_TYPE_ARRAY: ArrayValue,
 701     native_bt.VALUE_TYPE_MAP: MapValue,
 702 }