bindings/python/bt2/bt2/values.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
  36     if status == native_bt.VALUE_STATUS_FROZEN:
  37         raise bt2.Frozen('{} value object is frozen'.format(obj_name))
  38     elif status == native_bt.VALUE_STATUS_INVAL:
  39         # In practice, this should never happen, because arguments
  40         # should always be validated in this Python module before
  41         # calling the native functions.
  42         raise ValueError('unexpected invalid argument')
  43     else:
  44         # In practice, this should never happen, because arguments
  45         # should always be validated in this Python module before
  46         # calling the native functions.
  47         raise RuntimeError('unexpected error')
  48
  49
  50 def _create_from_ptr(ptr):
  51     if ptr is None or ptr == native_bt.value_null:
  52         return
  53
  54     typeid = native_bt.value_get_type(ptr)
  55     return _TYPE_TO_OBJ[typeid]._create_from_ptr(ptr)
  56
  57
  58 def create_value(value):
  59     if value is None:
  60         # null value object
  61         return
  62
  63     if isinstance(value, _Value):
  64         return value
  65
  66     if isinstance(value, bool):
  67         return BoolValue(value)
  68
  69     if isinstance(value, int):
  70         return IntegerValue(value)
  71
  72     if isinstance(value, float):
  73         return FloatValue(value)
  74
  75     if isinstance(value, str):
  76         return StringValue(value)
  77
  78     try:
  79         return MapValue(value)
  80     except:
  81         pass
  82
  83     try:
  84         return ArrayValue(value)
  85     except:
  86         pass
  87
  88     raise TypeError("cannot create value object from '{}' object".format(value.__class__.__name__))
  89
  90
  91 class _Value(object._Object, object._Freezable, metaclass=abc.ABCMeta):
  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('cannot create {} value object'.format(self._NAME.lower()))
 123
 124     def _is_frozen(self):
 125         return native_bt.value_is_frozen(self._ptr)
 126
 127     def _freeze(self):
 128         status = native_bt.value_freeze(self._ptr)
 129         self._handle_status(status)
 130
 131
 132 class _BasicCopy:
 133     def __copy__(self):
 134         return self.__class__(self.value)
 135
 136     def __deepcopy__(self, memo):
 137         copy = self.__copy__()
 138         memo[id(self)] = copy
 139         return copy
 140
 141
 142 @functools.total_ordering
 143 class _NumericValue(_Value, _BasicCopy):
 144     @staticmethod
 145     def _extract_value(other):
 146         if isinstance(other, _NumericValue):
 147             return other.value
 148
 149         if other is True or other is False:
 150             return other
 151
 152         if isinstance(other, numbers.Integral):
 153             return int(other)
 154
 155         if isinstance(other, numbers.Real):
 156             return float(other)
 157
 158         if isinstance(other, numbers.Complex):
 159             return complex(other)
 160
 161         raise TypeError("'{}' object is not a number object".format(other.__class__.__name__))
 162
 163     def __int__(self):
 164         return int(self.value)
 165
 166     def __float__(self):
 167         return float(self.value)
 168
 169     def __str__(self):
 170         return str(self.value)
 171
 172     def __lt__(self, other):
 173         if not isinstance(other, numbers.Number):
 174             raise TypeError('unorderable types: {}() < {}()'.format(self.__class__.__name__,
 175                                                                     other.__class__.__name__))
 176
 177         return self.value < float(other)
 178
 179     def __le__(self, other):
 180         if not isinstance(other, numbers.Number):
 181             raise TypeError('unorderable types: {}() <= {}()'.format(self.__class__.__name__,
 182                                                                      other.__class__.__name__))
 183
 184         return self.value <= float(other)
 185
 186     def _spec_eq(self, other):
 187         pass
 188
 189     def __eq__(self, other):
 190         if not isinstance(other, numbers.Number):
 191             return False
 192
 193         return self.value == complex(other)
 194
 195     def __rmod__(self, other):
 196         return self._extract_value(other) % self.value
 197
 198     def __mod__(self, other):
 199         return self.value % self._extract_value(other)
 200
 201     def __rfloordiv__(self, other):
 202         return self._extract_value(other) // self.value
 203
 204     def __floordiv__(self, other):
 205         return self.value // self._extract_value(other)
 206
 207     def __round__(self, ndigits=None):
 208         if ndigits is None:
 209             return round(self.value)
 210         else:
 211             return round(self.value, ndigits)
 212
 213     def __ceil__(self):
 214         return math.ceil(self.value)
 215
 216     def __floor__(self):
 217         return math.floor(self.value)
 218
 219     def __trunc__(self):
 220         return int(self.value)
 221
 222     def __abs__(self):
 223         return abs(self.value)
 224
 225     def __add__(self, other):
 226         return self.value + self._extract_value(other)
 227
 228     def __radd__(self, other):
 229         return self.__add__(other)
 230
 231     def __neg__(self):
 232         return -self.value
 233
 234     def __pos__(self):
 235         return +self.value
 236
 237     def __mul__(self, other):
 238         return self.value * self._extract_value(other)
 239
 240     def __rmul__(self, other):
 241         return self.__mul__(other)
 242
 243     def __truediv__(self, other):
 244         return self.value / self._extract_value(other)
 245
 246     def __rtruediv__(self, other):
 247         return self._extract_value(other) / self.value
 248
 249     def __pow__(self, exponent):
 250         return self.value ** self._extract_value(exponent)
 251
 252     def __rpow__(self, base):
 253         return self._extract_value(base) ** self.value
 254
 255     def __iadd__(self, other):
 256         self.value = self + other
 257         return self
 258
 259     def __isub__(self, other):
 260         self.value = self - other
 261         return self
 262
 263     def __imul__(self, other):
 264         self.value = self * other
 265         return self
 266
 267     def __itruediv__(self, other):
 268         self.value = self / other
 269         return self
 270
 271     def __ifloordiv__(self, other):
 272         self.value = self // other
 273         return self
 274
 275     def __imod__(self, other):
 276         self.value = self % other
 277         return self
 278
 279     def __ipow__(self, other):
 280         self.value = self ** other
 281         return self
 282
 283
 284 class _IntegralValue(_NumericValue, numbers.Integral):
 285     def __lshift__(self, other):
 286         return self.value << self._extract_value(other)
 287
 288     def __rlshift__(self, other):
 289         return self._extract_value(other) << self.value
 290
 291     def __rshift__(self, other):
 292         return self.value >> self._extract_value(other)
 293
 294     def __rrshift__(self, other):
 295         return self._extract_value(other) >> self.value
 296
 297     def __and__(self, other):
 298         return self.value & self._extract_value(other)
 299
 300     def __rand__(self, other):
 301         return self._extract_value(other) & self.value
 302
 303     def __xor__(self, other):
 304         return self.value ^ self._extract_value(other)
 305
 306     def __rxor__(self, other):
 307         return self._extract_value(other) ^ self.value
 308
 309     def __or__(self, other):
 310         return self.value | self._extract_value(other)
 311
 312     def __ror__(self, other):
 313         return self._extract_value(other) | self.value
 314
 315     def __invert__(self):
 316         return ~self.value
 317
 318     def __ilshift__(self, other):
 319         self.value = self << other
 320         return self
 321
 322     def __irshift__(self, other):
 323         self.value = self >> other
 324         return self
 325
 326     def __iand__(self, other):
 327         self.value = self & other
 328         return self
 329
 330     def __ixor__(self, other):
 331         self.value = self ^ other
 332         return self
 333
 334     def __ior__(self, other):
 335         self.value = self | other
 336         return self
 337
 338
 339 class _RealValue(_NumericValue, numbers.Real):
 340     pass
 341
 342
 343 class BoolValue(_Value, _BasicCopy):
 344     _NAME = 'Boolean'
 345
 346     def __init__(self, value=None):
 347         if value is None:
 348             ptr = native_bt.value_bool_create()
 349         else:
 350             ptr = native_bt.value_bool_create_init(self._value_to_bool(value))
 351
 352         self._check_create_status(ptr)
 353         super().__init__(ptr)
 354
 355     def _spec_eq(self, other):
 356         if isinstance(other, numbers.Number):
 357             return self.value == bool(other)
 358
 359     def __bool__(self):
 360         return self.value
 361
 362     def __str__(self):
 363         return str(self.value)
 364
 365     def _value_to_bool(self, value):
 366         if isinstance(value, BoolValue):
 367             value = value.value
 368
 369         if not isinstance(value, bool):
 370             raise TypeError("'{}' object is not a 'bool' or 'BoolValue' object".format(value.__class__))
 371
 372         return int(value)
 373
 374     @property
 375     def value(self):
 376         status, value = native_bt.value_bool_get(self._ptr)
 377         assert(status == native_bt.VALUE_STATUS_OK)
 378         return value > 0
 379
 380     @value.setter
 381     def value(self, value):
 382         status = native_bt.value_bool_set(self._ptr, self._value_to_bool(value))
 383         self._handle_status(status)
 384
 385
 386 class IntegerValue(_IntegralValue):
 387     _NAME = 'Integer'
 388
 389     def __init__(self, value=None):
 390         if value is None:
 391             ptr = native_bt.value_integer_create()
 392         else:
 393             ptr = native_bt.value_integer_create_init(self._value_to_int(value))
 394
 395         self._check_create_status(ptr)
 396         super().__init__(ptr)
 397
 398     def _value_to_int(self, value):
 399         if not isinstance(value, numbers.Real):
 400             raise TypeError('expecting a number object')
 401
 402         value = int(value)
 403         utils._check_int64(value)
 404         return value
 405
 406     @property
 407     def value(self):
 408         status, value = native_bt.value_integer_get(self._ptr)
 409         assert(status == native_bt.VALUE_STATUS_OK)
 410         return value
 411
 412     @value.setter
 413     def value(self, value):
 414         status = native_bt.value_integer_set(self._ptr, self._value_to_int(value))
 415         self._handle_status(status)
 416
 417
 418 class FloatValue(_RealValue):
 419     _NAME = 'Floating point number'
 420
 421     def __init__(self, value=None):
 422         if value is None:
 423             ptr = native_bt.value_float_create()
 424         else:
 425             value = self._value_to_float(value)
 426             ptr = native_bt.value_float_create_init(value)
 427
 428         self._check_create_status(ptr)
 429         super().__init__(ptr)
 430
 431     def _value_to_float(self, value):
 432         if not isinstance(value, numbers.Real):
 433             raise TypeError("expecting a real number object")
 434
 435         return float(value)
 436
 437     @property
 438     def value(self):
 439         status, value = native_bt.value_float_get(self._ptr)
 440         assert(status == native_bt.VALUE_STATUS_OK)
 441         return value
 442
 443     @value.setter
 444     def value(self, value):
 445         value = self._value_to_float(value)
 446         status = native_bt.value_float_set(self._ptr, value)
 447         self._handle_status(status)
 448
 449
 450 @functools.total_ordering
 451 class StringValue(_BasicCopy, collections.abc.Sequence, _Value):
 452     _NAME = 'String'
 453
 454     def __init__(self, value=None):
 455         if value is None:
 456             ptr = native_bt.value_string_create()
 457         else:
 458             ptr = native_bt.value_string_create_init(self._value_to_str(value))
 459
 460         self._check_create_status(ptr)
 461         super().__init__(ptr)
 462
 463     def _value_to_str(self, value):
 464         if isinstance(value, self.__class__):
 465             value = value.value
 466
 467         utils._check_str(value)
 468         return value
 469
 470     @property
 471     def value(self):
 472         status, value = native_bt.value_string_get(self._ptr)
 473         assert(status == native_bt.VALUE_STATUS_OK)
 474         return value
 475
 476     @value.setter
 477     def value(self, value):
 478         status = native_bt.value_string_set(self._ptr, self._value_to_str(value))
 479         self._handle_status(status)
 480
 481     def _spec_eq(self, other):
 482         try:
 483             return self.value == self._value_to_str(other)
 484         except:
 485             return
 486
 487     def __le__(self, other):
 488         return self.value <= self._value_to_str(other)
 489
 490     def __lt__(self, other):
 491         return self.value < self._value_to_str(other)
 492
 493     def __bool__(self):
 494         return bool(self.value)
 495
 496     def __str__(self):
 497         return self.value
 498
 499     def __getitem__(self, index):
 500         return self.value[index]
 501
 502     def __len__(self):
 503         return len(self.value)
 504
 505     def __iadd__(self, value):
 506         curvalue = self.value
 507         curvalue += self._value_to_str(value)
 508         self.value = curvalue
 509         return self
 510
 511
 512 class _Container:
 513     def __bool__(self):
 514         return len(self) != 0
 515
 516     def __copy__(self):
 517         return self.__class__(self)
 518
 519     def __deepcopy__(self, memo):
 520         ptr = native_bt.value_copy(self._ptr)
 521
 522         if ptr is None:
 523             raise RuntimeError('unexpected error: cannot deep-copy {} value object'.format(self._NAME))
 524
 525         copy = self.__class__._create_from_ptr(ptr)
 526         memo[id(self)] = copy
 527         return copy
 528
 529     def __delitem__(self, index):
 530         raise NotImplementedError
 531
 532
 533 class ArrayValue(_Container, collections.abc.MutableSequence, _Value):
 534     _NAME = 'Array'
 535
 536     def __init__(self, value=None):
 537         ptr = native_bt.value_array_create()
 538         self._check_create_status(ptr)
 539         super().__init__(ptr)
 540
 541         # Python will raise a TypeError if there's anything wrong with
 542         # the iterable protocol.
 543         if value is not None:
 544             for elem in value:
 545                 self.append(elem)
 546
 547     def _spec_eq(self, other):
 548         try:
 549             if len(self) != len(other):
 550                 # early mismatch
 551                 return False
 552
 553             for self_elem, other_elem in zip(self, other):
 554                 if self_elem != other_elem:
 555                     return False
 556
 557             return True
 558         except:
 559             return
 560
 561     def __len__(self):
 562         size = native_bt.value_array_size(self._ptr)
 563         assert(size >= 0)
 564         return size
 565
 566     def _check_index(self, index):
 567         # TODO: support slices also
 568         if not isinstance(index, numbers.Integral):
 569             raise TypeError("'{}' object is not an integral number object: invalid index".format(index.__class__.__name__))
 570
 571         index = int(index)
 572
 573         if index < 0 or index >= len(self):
 574             raise IndexError('array value object index is out of range')
 575
 576     def __getitem__(self, index):
 577         self._check_index(index)
 578         ptr = native_bt.value_array_get(self._ptr, index)
 579         assert(ptr)
 580         return _create_from_ptr(ptr)
 581
 582     def __setitem__(self, index, value):
 583         self._check_index(index)
 584         value = create_value(value)
 585
 586         if value is None:
 587             ptr = native_bt.value_null
 588         else:
 589             ptr = value._ptr
 590
 591         status = native_bt.value_array_set(self._ptr, index, ptr)
 592         self._handle_status(status)
 593
 594     def append(self, value):
 595         value = create_value(value)
 596
 597         if value is None:
 598             ptr = native_bt.value_null
 599         else:
 600             ptr = value._ptr
 601
 602         status = native_bt.value_array_append(self._ptr, ptr)
 603         self._handle_status(status)
 604
 605     def __iadd__(self, iterable):
 606         # Python will raise a TypeError if there's anything wrong with
 607         # the iterable protocol.
 608         for elem in iterable:
 609             self.append(elem)
 610
 611         return self
 612
 613     def __str__(self):
 614         strings = []
 615
 616         for elem in self:
 617             if isinstance(elem, StringValue):
 618                 strings.append(repr(elem.value))
 619             else:
 620                 strings.append(str(elem))
 621
 622         return '[{}]'.format(', '.join(strings))
 623
 624     def insert(self, value):
 625         raise NotImplementedError
 626
 627
 628 class _MapValueKeyIterator(collections.abc.Iterator):
 629     def __init__(self, map_obj):
 630         self._map_obj = map_obj
 631         self._at = 0
 632         keys_ptr = native_bt.value_map_get_keys_private(map_obj._ptr)
 633
 634         if keys_ptr is None:
 635             raise RuntimeError('unexpected error: cannot get map value object keys')
 636
 637         self._keys = _create_from_ptr(keys_ptr)
 638
 639     def __next__(self):
 640         if self._at == len(self._map_obj):
 641             raise StopIteration
 642
 643         key = self._keys[self._at]
 644         self._at += 1
 645         return str(key)
 646
 647
 648 class MapValue(_Container, collections.abc.MutableMapping, _Value):
 649     _NAME = 'Map'
 650
 651     def __init__(self, value=None):
 652         ptr = native_bt.value_map_create()
 653         self._check_create_status(ptr)
 654         super().__init__(ptr)
 655
 656         # Python will raise a TypeError if there's anything wrong with
 657         # the iterable/mapping protocol.
 658         if value is not None:
 659             for key, elem in value.items():
 660                 self[key] = elem
 661
 662     def __eq__(self, other):
 663         return _Value.__eq__(self, other)
 664
 665     def __ne__(self, other):
 666         return _Value.__ne__(self, other)
 667
 668     def _spec_eq(self, other):
 669         try:
 670             if len(self) != len(other):
 671                 # early mismatch
 672                 return False
 673
 674             for self_key in self:
 675                 if self_key not in other:
 676                     return False
 677
 678                 self_value = self[self_key]
 679                 other_value = other[self_key]
 680
 681                 if self_value != other_value:
 682                     return False
 683
 684             return True
 685         except:
 686             return
 687
 688     def __len__(self):
 689         size = native_bt.value_map_size(self._ptr)
 690         assert(size >= 0)
 691         return size
 692
 693     def __contains__(self, key):
 694         self._check_key_type(key)
 695         return native_bt.value_map_has_key(self._ptr, key)
 696
 697     def _check_key_type(self, key):
 698         utils._check_str(key)
 699
 700     def _check_key(self, key):
 701         if key not in self:
 702             raise KeyError(key)
 703
 704     def __getitem__(self, key):
 705         self._check_key(key)
 706         ptr = native_bt.value_map_get(self._ptr, key)
 707         assert(ptr)
 708         return _create_from_ptr(ptr)
 709
 710     def __iter__(self):
 711         return _MapValueKeyIterator(self)
 712
 713     def __setitem__(self, key, value):
 714         self._check_key_type(key)
 715         value = create_value(value)
 716
 717         if value is None:
 718             ptr = native_bt.value_null
 719         else:
 720             ptr = value._ptr
 721
 722         status = native_bt.value_map_insert(self._ptr, key, ptr)
 723         self._handle_status(status)
 724
 725     def __str__(self):
 726         strings = []
 727
 728         for key, elem in self.items():
 729             if isinstance(elem, StringValue):
 730                 value = repr(elem.value)
 731             else:
 732                 value = str(elem)
 733
 734             strings.append('{}: {}'.format(repr(key), value))
 735
 736         return '{{{}}}'.format(', '.join(strings))
 737
 738
 739 _TYPE_TO_OBJ = {
 740     native_bt.VALUE_TYPE_BOOL: BoolValue,
 741     native_bt.VALUE_TYPE_INTEGER: IntegerValue,
 742     native_bt.VALUE_TYPE_FLOAT: FloatValue,
 743     native_bt.VALUE_TYPE_STRING: StringValue,
 744     native_bt.VALUE_TYPE_ARRAY: ArrayValue,
 745     native_bt.VALUE_TYPE_MAP: MapValue,
 746 }