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 __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     def __init__(self, value=None):
 371         if value is None:
 372             ptr = self._create_default_value()
 373         else:
 374             ptr = self._create_value(self._value_to_int(value))
 375
 376         self._check_create_status(ptr)
 377         super().__init__(ptr)
 378
 379     def _value_to_int(self, value):
 380         if not isinstance(value, numbers.Real):
 381             raise TypeError('expecting a number object')
 382
 383         value = int(value)
 384         self._check_int_range(value)
 385         return value
 386
 387     @property
 388     def _value(self):
 389         return self._get_value(self._ptr)
 390
 391     def _prop_set_value(self, value):
 392         self._set_value(self._ptr, self._value_to_int(value))
 393
 394     value = property(fset=_prop_set_value)
 395
 396
 397 class UnsignedIntegerValue(_IntegerValue):
 398     _check_int_range = staticmethod(utils._check_uint64)
 399     _create_default_value = staticmethod(native_bt.value_unsigned_integer_create)
 400     _create_value = staticmethod(native_bt.value_unsigned_integer_create_init)
 401     _set_value = staticmethod(native_bt.value_unsigned_integer_set)
 402     _get_value = staticmethod(native_bt.value_unsigned_integer_get)
 403
 404
 405 class SignedIntegerValue(_IntegerValue):
 406     _check_int_range = staticmethod(utils._check_int64)
 407     _create_default_value = staticmethod(native_bt.value_signed_integer_create)
 408     _create_value = staticmethod(native_bt.value_signed_integer_create_init)
 409     _set_value = staticmethod(native_bt.value_signed_integer_set)
 410     _get_value = staticmethod(native_bt.value_signed_integer_get)
 411
 412
 413 class RealValue(_RealValue):
 414     _NAME = 'Real number'
 415
 416     def __init__(self, value=None):
 417         if value is None:
 418             ptr = native_bt.value_real_create()
 419         else:
 420             value = self._value_to_float(value)
 421             ptr = native_bt.value_real_create_init(value)
 422
 423         self._check_create_status(ptr)
 424         super().__init__(ptr)
 425
 426     def _value_to_float(self, value):
 427         if not isinstance(value, numbers.Real):
 428             raise TypeError("expecting a real number object")
 429
 430         return float(value)
 431
 432     @property
 433     def _value(self):
 434         return native_bt.value_real_get(self._ptr)
 435
 436     def _set_value(self, value):
 437         native_bt.value_real_set(self._ptr, self._value_to_float(value))
 438
 439     value = property(fset=_set_value)
 440
 441
 442 @functools.total_ordering
 443 class StringValue(collections.abc.Sequence, _Value):
 444     _NAME = 'String'
 445
 446     def __init__(self, value=None):
 447         if value is None:
 448             ptr = native_bt.value_string_create()
 449         else:
 450             ptr = native_bt.value_string_create_init(self._value_to_str(value))
 451
 452         self._check_create_status(ptr)
 453         super().__init__(ptr)
 454
 455     def _value_to_str(self, value):
 456         if isinstance(value, self.__class__):
 457             value = value._value
 458
 459         utils._check_str(value)
 460         return value
 461
 462     @property
 463     def _value(self):
 464         return native_bt.value_string_get(self._ptr)
 465
 466     def _set_value(self, value):
 467         status = native_bt.value_string_set(self._ptr, self._value_to_str(value))
 468         self._handle_status(status)
 469
 470     value = property(fset=_set_value)
 471
 472     def _spec_eq(self, other):
 473         try:
 474             return self._value == self._value_to_str(other)
 475         except:
 476             return
 477
 478     def __le__(self, other):
 479         return self._value <= self._value_to_str(other)
 480
 481     def __lt__(self, other):
 482         return self._value < self._value_to_str(other)
 483
 484     def __bool__(self):
 485         return bool(self._value)
 486
 487     def __repr__(self):
 488         return repr(self._value)
 489
 490     def __str__(self):
 491         return self._value
 492
 493     def __getitem__(self, index):
 494         return self._value[index]
 495
 496     def __len__(self):
 497         return len(self._value)
 498
 499     def __iadd__(self, value):
 500         curvalue = self._value
 501         curvalue += self._value_to_str(value)
 502         self.value = curvalue
 503         return self
 504
 505
 506 class _Container:
 507     def __bool__(self):
 508         return len(self) != 0
 509
 510     def __delitem__(self, index):
 511         raise NotImplementedError
 512
 513
 514 class ArrayValue(_Container, collections.abc.MutableSequence, _Value):
 515     _NAME = 'Array'
 516
 517     def __init__(self, value=None):
 518         ptr = native_bt.value_array_create()
 519         self._check_create_status(ptr)
 520         super().__init__(ptr)
 521
 522         # Python will raise a TypeError if there's anything wrong with
 523         # the iterable protocol.
 524         if value is not None:
 525             for elem in value:
 526                 self.append(elem)
 527
 528     def _spec_eq(self, other):
 529         try:
 530             if len(self) != len(other):
 531                 # early mismatch
 532                 return False
 533
 534             for self_elem, other_elem in zip(self, other):
 535                 if self_elem != other_elem:
 536                     return False
 537
 538             return True
 539         except:
 540             return
 541
 542     def __len__(self):
 543         size = native_bt.value_array_get_size(self._ptr)
 544         assert(size >= 0)
 545         return size
 546
 547     def _check_index(self, index):
 548         # TODO: support slices also
 549         if not isinstance(index, numbers.Integral):
 550             raise TypeError("'{}' object is not an integral number object: invalid index".format(index.__class__.__name__))
 551
 552         index = int(index)
 553
 554         if index < 0 or index >= len(self):
 555             raise IndexError('array value object index is out of range')
 556
 557     def __getitem__(self, index):
 558         self._check_index(index)
 559         ptr = native_bt.value_array_borrow_element_by_index(self._ptr, index)
 560         assert(ptr)
 561         return _create_from_ptr_and_get_ref(ptr)
 562
 563     def __setitem__(self, index, value):
 564         self._check_index(index)
 565         value = create_value(value)
 566
 567         if value is None:
 568             ptr = native_bt.value_null
 569         else:
 570             ptr = value._ptr
 571
 572         status = native_bt.value_array_set_element_by_index(
 573             self._ptr, index, ptr)
 574         self._handle_status(status)
 575
 576     def append(self, value):
 577         value = create_value(value)
 578
 579         if value is None:
 580             ptr = native_bt.value_null
 581         else:
 582             ptr = value._ptr
 583
 584         status = native_bt.value_array_append_element(self._ptr, ptr)
 585         self._handle_status(status)
 586
 587     def __iadd__(self, iterable):
 588         # Python will raise a TypeError if there's anything wrong with
 589         # the iterable protocol.
 590         for elem in iterable:
 591             self.append(elem)
 592
 593         return self
 594
 595     def __repr__(self):
 596         return '[{}]'.format(', '.join([repr(v) for v in self]))
 597
 598     def insert(self, value):
 599         raise NotImplementedError
 600
 601
 602 class _MapValueKeyIterator(collections.abc.Iterator):
 603     def __init__(self, map_obj):
 604         self._map_obj = map_obj
 605         self._at = 0
 606         keys_ptr = native_bt.value_map_get_keys(map_obj._ptr)
 607
 608         if keys_ptr is None:
 609             raise RuntimeError('unexpected error: cannot get map value object keys')
 610
 611         self._keys = _create_from_ptr(keys_ptr)
 612
 613     def __next__(self):
 614         if self._at == len(self._map_obj):
 615             raise StopIteration
 616
 617         key = self._keys[self._at]
 618         self._at += 1
 619         return str(key)
 620
 621
 622 class MapValue(_Container, collections.abc.MutableMapping, _Value):
 623     _NAME = 'Map'
 624
 625     def __init__(self, value=None):
 626         ptr = native_bt.value_map_create()
 627         self._check_create_status(ptr)
 628         super().__init__(ptr)
 629
 630         # Python will raise a TypeError if there's anything wrong with
 631         # the iterable/mapping protocol.
 632         if value is not None:
 633             for key, elem in value.items():
 634                 self[key] = elem
 635
 636     def __eq__(self, other):
 637         return _Value.__eq__(self, other)
 638
 639     def __ne__(self, other):
 640         return _Value.__ne__(self, other)
 641
 642     def _spec_eq(self, other):
 643         try:
 644             if len(self) != len(other):
 645                 # early mismatch
 646                 return False
 647
 648             for self_key in self:
 649                 if self_key not in other:
 650                     return False
 651
 652                 self_value = self[self_key]
 653                 other_value = other[self_key]
 654
 655                 if self_value != other_value:
 656                     return False
 657
 658             return True
 659         except:
 660             return
 661
 662     def __len__(self):
 663         size = native_bt.value_map_get_size(self._ptr)
 664         assert(size >= 0)
 665         return size
 666
 667     def __contains__(self, key):
 668         self._check_key_type(key)
 669         return native_bt.value_map_has_entry(self._ptr, key)
 670
 671     def _check_key_type(self, key):
 672         utils._check_str(key)
 673
 674     def _check_key(self, key):
 675         if key not in self:
 676             raise KeyError(key)
 677
 678     def __getitem__(self, key):
 679         self._check_key(key)
 680         ptr = native_bt.value_map_borrow_entry_value(self._ptr, key)
 681         assert(ptr)
 682         return _create_from_ptr_and_get_ref(ptr)
 683
 684     def __iter__(self):
 685         return _MapValueKeyIterator(self)
 686
 687     def __setitem__(self, key, value):
 688         self._check_key_type(key)
 689         value = create_value(value)
 690
 691         if value is None:
 692             ptr = native_bt.value_null
 693         else:
 694             ptr = value._ptr
 695
 696         status = native_bt.value_map_insert_entry(self._ptr, key, ptr)
 697         self._handle_status(status)
 698
 699     def __repr__(self):
 700         items = ['{}: {}'.format(repr(k), repr(v)) for k, v in self.items()]
 701         return '{{{}}}'.format(', '.join(items))
 702
 703
 704 _TYPE_TO_OBJ = {
 705     native_bt.VALUE_TYPE_BOOL: BoolValue,
 706     native_bt.VALUE_TYPE_UNSIGNED_INTEGER: UnsignedIntegerValue,
 707     native_bt.VALUE_TYPE_SIGNED_INTEGER: SignedIntegerValue,
 708     native_bt.VALUE_TYPE_REAL: RealValue,
 709     native_bt.VALUE_TYPE_STRING: StringValue,
 710     native_bt.VALUE_TYPE_ARRAY: ArrayValue,
 711     native_bt.VALUE_TYPE_MAP: MapValue,
 712 }