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 IntegerValue(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 = native_bt.value_get_ref
  90     _put_ref = 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 __le__(self, other):
 164         if not isinstance(other, numbers.Number):
 165             raise TypeError('unorderable types: {}() <= {}()'.format(self.__class__.__name__,
 166                                                                      other.__class__.__name__))
 167
 168         return self._value <= float(other)
 169
 170     def _spec_eq(self, other):
 171         pass
 172
 173     def __eq__(self, other):
 174         if not isinstance(other, numbers.Number):
 175             return False
 176
 177         return self._value == complex(other)
 178
 179     def __rmod__(self, other):
 180         return self._extract_value(other) % self._value
 181
 182     def __mod__(self, other):
 183         return self._value % self._extract_value(other)
 184
 185     def __rfloordiv__(self, other):
 186         return self._extract_value(other) // self._value
 187
 188     def __floordiv__(self, other):
 189         return self._value // self._extract_value(other)
 190
 191     def __round__(self, ndigits=None):
 192         if ndigits is None:
 193             return round(self._value)
 194         else:
 195             return round(self._value, ndigits)
 196
 197     def __ceil__(self):
 198         return math.ceil(self._value)
 199
 200     def __floor__(self):
 201         return math.floor(self._value)
 202
 203     def __trunc__(self):
 204         return int(self._value)
 205
 206     def __abs__(self):
 207         return abs(self._value)
 208
 209     def __add__(self, other):
 210         return self._value + self._extract_value(other)
 211
 212     def __radd__(self, other):
 213         return self.__add__(other)
 214
 215     def __neg__(self):
 216         return -self._value
 217
 218     def __pos__(self):
 219         return +self._value
 220
 221     def __mul__(self, other):
 222         return self._value * self._extract_value(other)
 223
 224     def __rmul__(self, other):
 225         return self.__mul__(other)
 226
 227     def __truediv__(self, other):
 228         return self._value / self._extract_value(other)
 229
 230     def __rtruediv__(self, other):
 231         return self._extract_value(other) / self._value
 232
 233     def __pow__(self, exponent):
 234         return self._value ** self._extract_value(exponent)
 235
 236     def __rpow__(self, base):
 237         return self._extract_value(base) ** self._value
 238
 239     def __iadd__(self, other):
 240         self.value = self + other
 241         return self
 242
 243     def __isub__(self, other):
 244         self.value = self - other
 245         return self
 246
 247     def __imul__(self, other):
 248         self.value = self * other
 249         return self
 250
 251     def __itruediv__(self, other):
 252         self.value = self / other
 253         return self
 254
 255     def __ifloordiv__(self, other):
 256         self.value = self // other
 257         return self
 258
 259     def __imod__(self, other):
 260         self.value = self % other
 261         return self
 262
 263     def __ipow__(self, other):
 264         self.value = self ** other
 265         return self
 266
 267
 268 class _IntegralValue(_NumericValue, numbers.Integral):
 269     def __lshift__(self, other):
 270         return self._value << self._extract_value(other)
 271
 272     def __rlshift__(self, other):
 273         return self._extract_value(other) << self._value
 274
 275     def __rshift__(self, other):
 276         return self._value >> self._extract_value(other)
 277
 278     def __rrshift__(self, other):
 279         return self._extract_value(other) >> self._value
 280
 281     def __and__(self, other):
 282         return self._value & self._extract_value(other)
 283
 284     def __rand__(self, other):
 285         return self._extract_value(other) & self._value
 286
 287     def __xor__(self, other):
 288         return self._value ^ self._extract_value(other)
 289
 290     def __rxor__(self, other):
 291         return self._extract_value(other) ^ self._value
 292
 293     def __or__(self, other):
 294         return self._value | self._extract_value(other)
 295
 296     def __ror__(self, other):
 297         return self._extract_value(other) | self._value
 298
 299     def __invert__(self):
 300         return ~self._value
 301
 302     def __ilshift__(self, other):
 303         self.value = self << other
 304         return self
 305
 306     def __irshift__(self, other):
 307         self.value = self >> other
 308         return self
 309
 310     def __iand__(self, other):
 311         self.value = self & other
 312         return self
 313
 314     def __ixor__(self, other):
 315         self.value = self ^ other
 316         return self
 317
 318     def __ior__(self, other):
 319         self.value = self | other
 320         return self
 321
 322
 323 class _RealValue(_NumericValue, numbers.Real):
 324     pass
 325
 326
 327 class BoolValue(_Value):
 328     _NAME = 'Boolean'
 329
 330     def __init__(self, value=None):
 331         if value is None:
 332             ptr = native_bt.value_bool_create()
 333         else:
 334             ptr = native_bt.value_bool_create_init(self._value_to_bool(value))
 335
 336         self._check_create_status(ptr)
 337         super().__init__(ptr)
 338
 339     def _spec_eq(self, other):
 340         if isinstance(other, numbers.Number):
 341             return self._value == bool(other)
 342
 343     def __bool__(self):
 344         return self._value
 345
 346     def __repr__(self):
 347         return repr(self._value)
 348
 349     def _value_to_bool(self, value):
 350         if isinstance(value, BoolValue):
 351             value = value._value
 352
 353         if not isinstance(value, bool):
 354             raise TypeError("'{}' object is not a 'bool' or 'BoolValue' object".format(value.__class__))
 355
 356         return int(value)
 357
 358     @property
 359     def _value(self):
 360         value = native_bt.value_bool_get(self._ptr)
 361         return value != 0
 362
 363     def _set_value(self, value):
 364         native_bt.value_bool_set(self._ptr, self._value_to_bool(value))
 365
 366     value = property(fset=_set_value)
 367
 368
 369 class IntegerValue(_IntegralValue):
 370     _NAME = 'Integer'
 371
 372     def __init__(self, value=None):
 373         if value is None:
 374             ptr = native_bt.value_integer_create()
 375         else:
 376             ptr = native_bt.value_integer_create_init(self._value_to_int(value))
 377
 378         self._check_create_status(ptr)
 379         super().__init__(ptr)
 380
 381     def _value_to_int(self, value):
 382         if not isinstance(value, numbers.Real):
 383             raise TypeError('expecting a number object')
 384
 385         value = int(value)
 386         utils._check_int64(value)
 387         return value
 388
 389     @property
 390     def _value(self):
 391         return native_bt.value_integer_get(self._ptr)
 392
 393     def _set_value(self, value):
 394         native_bt.value_integer_set(self._ptr, self._value_to_int(value))
 395
 396     value = property(fset=_set_value)
 397
 398
 399 class RealValue(_RealValue):
 400     _NAME = 'Real number'
 401
 402     def __init__(self, value=None):
 403         if value is None:
 404             ptr = native_bt.value_real_create()
 405         else:
 406             value = self._value_to_float(value)
 407             ptr = native_bt.value_real_create_init(value)
 408
 409         self._check_create_status(ptr)
 410         super().__init__(ptr)
 411
 412     def _value_to_float(self, value):
 413         if not isinstance(value, numbers.Real):
 414             raise TypeError("expecting a real number object")
 415
 416         return float(value)
 417
 418     @property
 419     def _value(self):
 420         return native_bt.value_real_get(self._ptr)
 421
 422     def _set_value(self, value):
 423         native_bt.value_real_set(self._ptr, self._value_to_float(value))
 424
 425     value = property(fset=_set_value)
 426
 427
 428 @functools.total_ordering
 429 class StringValue(collections.abc.Sequence, _Value):
 430     _NAME = 'String'
 431
 432     def __init__(self, value=None):
 433         if value is None:
 434             ptr = native_bt.value_string_create()
 435         else:
 436             ptr = native_bt.value_string_create_init(self._value_to_str(value))
 437
 438         self._check_create_status(ptr)
 439         super().__init__(ptr)
 440
 441     def _value_to_str(self, value):
 442         if isinstance(value, self.__class__):
 443             value = value._value
 444
 445         utils._check_str(value)
 446         return value
 447
 448     @property
 449     def _value(self):
 450         return native_bt.value_string_get(self._ptr)
 451
 452     def _set_value(self, value):
 453         status = native_bt.value_string_set(self._ptr, self._value_to_str(value))
 454         self._handle_status(status)
 455
 456     value = property(fset=_set_value)
 457
 458     def _spec_eq(self, other):
 459         try:
 460             return self._value == self._value_to_str(other)
 461         except:
 462             return
 463
 464     def __le__(self, other):
 465         return self._value <= self._value_to_str(other)
 466
 467     def __lt__(self, other):
 468         return self._value < self._value_to_str(other)
 469
 470     def __bool__(self):
 471         return bool(self._value)
 472
 473     def __repr__(self):
 474         return repr(self._value)
 475
 476     def __str__(self):
 477         return self._value
 478
 479     def __getitem__(self, index):
 480         return self._value[index]
 481
 482     def __len__(self):
 483         return len(self._value)
 484
 485     def __iadd__(self, value):
 486         curvalue = self._value
 487         curvalue += self._value_to_str(value)
 488         self.value = curvalue
 489         return self
 490
 491
 492 class _Container:
 493     def __bool__(self):
 494         return len(self) != 0
 495
 496     def __delitem__(self, index):
 497         raise NotImplementedError
 498
 499
 500 class ArrayValue(_Container, collections.abc.MutableSequence, _Value):
 501     _NAME = 'Array'
 502
 503     def __init__(self, value=None):
 504         ptr = native_bt.value_array_create()
 505         self._check_create_status(ptr)
 506         super().__init__(ptr)
 507
 508         # Python will raise a TypeError if there's anything wrong with
 509         # the iterable protocol.
 510         if value is not None:
 511             for elem in value:
 512                 self.append(elem)
 513
 514     def _spec_eq(self, other):
 515         try:
 516             if len(self) != len(other):
 517                 # early mismatch
 518                 return False
 519
 520             for self_elem, other_elem in zip(self, other):
 521                 if self_elem != other_elem:
 522                     return False
 523
 524             return True
 525         except:
 526             return
 527
 528     def __len__(self):
 529         size = native_bt.value_array_get_size(self._ptr)
 530         assert(size >= 0)
 531         return size
 532
 533     def _check_index(self, index):
 534         # TODO: support slices also
 535         if not isinstance(index, numbers.Integral):
 536             raise TypeError("'{}' object is not an integral number object: invalid index".format(index.__class__.__name__))
 537
 538         index = int(index)
 539
 540         if index < 0 or index >= len(self):
 541             raise IndexError('array value object index is out of range')
 542
 543     def __getitem__(self, index):
 544         self._check_index(index)
 545         ptr = native_bt.value_array_borrow_element_by_index(self._ptr, index)
 546         assert(ptr)
 547         return _create_from_ptr_and_get_ref(ptr)
 548
 549     def __setitem__(self, index, value):
 550         self._check_index(index)
 551         value = create_value(value)
 552
 553         if value is None:
 554             ptr = native_bt.value_null
 555         else:
 556             ptr = value._ptr
 557
 558         status = native_bt.value_array_set_element_by_index(
 559             self._ptr, index, ptr)
 560         self._handle_status(status)
 561
 562     def append(self, value):
 563         value = create_value(value)
 564
 565         if value is None:
 566             ptr = native_bt.value_null
 567         else:
 568             ptr = value._ptr
 569
 570         status = native_bt.value_array_append_element(self._ptr, ptr)
 571         self._handle_status(status)
 572
 573     def __iadd__(self, iterable):
 574         # Python will raise a TypeError if there's anything wrong with
 575         # the iterable protocol.
 576         for elem in iterable:
 577             self.append(elem)
 578
 579         return self
 580
 581     def __repr__(self):
 582         return '[{}]'.format(', '.join([repr(v) for v in self]))
 583
 584     def insert(self, value):
 585         raise NotImplementedError
 586
 587
 588 class _MapValueKeyIterator(collections.abc.Iterator):
 589     def __init__(self, map_obj):
 590         self._map_obj = map_obj
 591         self._at = 0
 592         keys_ptr = native_bt.value_map_get_keys(map_obj._ptr)
 593
 594         if keys_ptr is None:
 595             raise RuntimeError('unexpected error: cannot get map value object keys')
 596
 597         self._keys = _create_from_ptr(keys_ptr)
 598
 599     def __next__(self):
 600         if self._at == len(self._map_obj):
 601             raise StopIteration
 602
 603         key = self._keys[self._at]
 604         self._at += 1
 605         return str(key)
 606
 607
 608 class MapValue(_Container, collections.abc.MutableMapping, _Value):
 609     _NAME = 'Map'
 610
 611     def __init__(self, value=None):
 612         ptr = native_bt.value_map_create()
 613         self._check_create_status(ptr)
 614         super().__init__(ptr)
 615
 616         # Python will raise a TypeError if there's anything wrong with
 617         # the iterable/mapping protocol.
 618         if value is not None:
 619             for key, elem in value.items():
 620                 self[key] = elem
 621
 622     def __eq__(self, other):
 623         return _Value.__eq__(self, other)
 624
 625     def __ne__(self, other):
 626         return _Value.__ne__(self, other)
 627
 628     def _spec_eq(self, other):
 629         try:
 630             if len(self) != len(other):
 631                 # early mismatch
 632                 return False
 633
 634             for self_key in self:
 635                 if self_key not in other:
 636                     return False
 637
 638                 self_value = self[self_key]
 639                 other_value = other[self_key]
 640
 641                 if self_value != other_value:
 642                     return False
 643
 644             return True
 645         except:
 646             return
 647
 648     def __len__(self):
 649         size = native_bt.value_map_get_size(self._ptr)
 650         assert(size >= 0)
 651         return size
 652
 653     def __contains__(self, key):
 654         self._check_key_type(key)
 655         return native_bt.value_map_has_entry(self._ptr, key)
 656
 657     def _check_key_type(self, key):
 658         utils._check_str(key)
 659
 660     def _check_key(self, key):
 661         if key not in self:
 662             raise KeyError(key)
 663
 664     def __getitem__(self, key):
 665         self._check_key(key)
 666         ptr = native_bt.value_map_borrow_entry_value(self._ptr, key)
 667         assert(ptr)
 668         return _create_from_ptr_and_get_ref(ptr)
 669
 670     def __iter__(self):
 671         return _MapValueKeyIterator(self)
 672
 673     def __setitem__(self, key, value):
 674         self._check_key_type(key)
 675         value = create_value(value)
 676
 677         if value is None:
 678             ptr = native_bt.value_null
 679         else:
 680             ptr = value._ptr
 681
 682         status = native_bt.value_map_insert_entry(self._ptr, key, ptr)
 683         self._handle_status(status)
 684
 685     def __repr__(self):
 686         items = ['{}: {}'.format(repr(k), repr(v)) for k, v in self.items()]
 687         return '{{{}}}'.format(', '.join(items))
 688
 689
 690 _TYPE_TO_OBJ = {
 691     native_bt.VALUE_TYPE_BOOL: BoolValue,
 692     native_bt.VALUE_TYPE_INTEGER: IntegerValue,
 693     native_bt.VALUE_TYPE_REAL: RealValue,
 694     native_bt.VALUE_TYPE_STRING: StringValue,
 695     native_bt.VALUE_TYPE_ARRAY: ArrayValue,
 696     native_bt.VALUE_TYPE_MAP: MapValue,
 697 }