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     def _set_value(self, value):
 381         status = native_bt.value_bool_set(self._ptr, self._value_to_bool(value))
 382         self._handle_status(status)
 383
 384     value = property(fset=_set_value)
 385
 386
 387 class IntegerValue(_IntegralValue):
 388     _NAME = 'Integer'
 389
 390     def __init__(self, value=None):
 391         if value is None:
 392             ptr = native_bt.value_integer_create()
 393         else:
 394             ptr = native_bt.value_integer_create_init(self._value_to_int(value))
 395
 396         self._check_create_status(ptr)
 397         super().__init__(ptr)
 398
 399     def _value_to_int(self, value):
 400         if not isinstance(value, numbers.Real):
 401             raise TypeError('expecting a number object')
 402
 403         value = int(value)
 404         utils._check_int64(value)
 405         return value
 406
 407     @property
 408     def _value(self):
 409         status, value = native_bt.value_integer_get(self._ptr)
 410         assert(status == native_bt.VALUE_STATUS_OK)
 411         return value
 412
 413     def _set_value(self, value):
 414         status = native_bt.value_integer_set(self._ptr, self._value_to_int(value))
 415         self._handle_status(status)
 416
 417     value = property(fset=_set_value)
 418
 419
 420 class FloatValue(_RealValue):
 421     _NAME = 'Floating point number'
 422
 423     def __init__(self, value=None):
 424         if value is None:
 425             ptr = native_bt.value_float_create()
 426         else:
 427             value = self._value_to_float(value)
 428             ptr = native_bt.value_float_create_init(value)
 429
 430         self._check_create_status(ptr)
 431         super().__init__(ptr)
 432
 433     def _value_to_float(self, value):
 434         if not isinstance(value, numbers.Real):
 435             raise TypeError("expecting a real number object")
 436
 437         return float(value)
 438
 439     @property
 440     def _value(self):
 441         status, value = native_bt.value_float_get(self._ptr)
 442         assert(status == native_bt.VALUE_STATUS_OK)
 443         return value
 444
 445     def _set_value(self, value):
 446         value = self._value_to_float(value)
 447         status = native_bt.value_float_set(self._ptr, value)
 448         self._handle_status(status)
 449
 450     value = property(fset=_set_value)
 451
 452
 453 @functools.total_ordering
 454 class StringValue(_BasicCopy, collections.abc.Sequence, _Value):
 455     _NAME = 'String'
 456
 457     def __init__(self, value=None):
 458         if value is None:
 459             ptr = native_bt.value_string_create()
 460         else:
 461             ptr = native_bt.value_string_create_init(self._value_to_str(value))
 462
 463         self._check_create_status(ptr)
 464         super().__init__(ptr)
 465
 466     def _value_to_str(self, value):
 467         if isinstance(value, self.__class__):
 468             value = value._value
 469
 470         utils._check_str(value)
 471         return value
 472
 473     @property
 474     def _value(self):
 475         status, value = native_bt.value_string_get(self._ptr)
 476         assert(status == native_bt.VALUE_STATUS_OK)
 477         return value
 478
 479     def _set_value(self, value):
 480         status = native_bt.value_string_set(self._ptr, self._value_to_str(value))
 481         self._handle_status(status)
 482
 483     value = property(fset=_set_value)
 484
 485     def _spec_eq(self, other):
 486         try:
 487             return self._value == self._value_to_str(other)
 488         except:
 489             return
 490
 491     def __le__(self, other):
 492         return self._value <= self._value_to_str(other)
 493
 494     def __lt__(self, other):
 495         return self._value < self._value_to_str(other)
 496
 497     def __bool__(self):
 498         return bool(self._value)
 499
 500     def __str__(self):
 501         return self._value
 502
 503     def __getitem__(self, index):
 504         return self._value[index]
 505
 506     def __len__(self):
 507         return len(self._value)
 508
 509     def __iadd__(self, value):
 510         curvalue = self._value
 511         curvalue += self._value_to_str(value)
 512         self.value = curvalue
 513         return self
 514
 515
 516 class _Container:
 517     def __bool__(self):
 518         return len(self) != 0
 519
 520     def __copy__(self):
 521         return self.__class__(self)
 522
 523     def __deepcopy__(self, memo):
 524         ptr = native_bt.value_copy(self._ptr)
 525
 526         if ptr is None:
 527             raise RuntimeError('unexpected error: cannot deep-copy {} value object'.format(self._NAME))
 528
 529         copy = self.__class__._create_from_ptr(ptr)
 530         memo[id(self)] = copy
 531         return copy
 532
 533     def __delitem__(self, index):
 534         raise NotImplementedError
 535
 536
 537 class ArrayValue(_Container, collections.abc.MutableSequence, _Value):
 538     _NAME = 'Array'
 539
 540     def __init__(self, value=None):
 541         ptr = native_bt.value_array_create()
 542         self._check_create_status(ptr)
 543         super().__init__(ptr)
 544
 545         # Python will raise a TypeError if there's anything wrong with
 546         # the iterable protocol.
 547         if value is not None:
 548             for elem in value:
 549                 self.append(elem)
 550
 551     def _spec_eq(self, other):
 552         try:
 553             if len(self) != len(other):
 554                 # early mismatch
 555                 return False
 556
 557             for self_elem, other_elem in zip(self, other):
 558                 if self_elem != other_elem:
 559                     return False
 560
 561             return True
 562         except:
 563             return
 564
 565     def __len__(self):
 566         size = native_bt.value_array_size(self._ptr)
 567         assert(size >= 0)
 568         return size
 569
 570     def _check_index(self, index):
 571         # TODO: support slices also
 572         if not isinstance(index, numbers.Integral):
 573             raise TypeError("'{}' object is not an integral number object: invalid index".format(index.__class__.__name__))
 574
 575         index = int(index)
 576
 577         if index < 0 or index >= len(self):
 578             raise IndexError('array value object index is out of range')
 579
 580     def __getitem__(self, index):
 581         self._check_index(index)
 582         ptr = native_bt.value_array_get(self._ptr, index)
 583         assert(ptr)
 584         return _create_from_ptr(ptr)
 585
 586     def __setitem__(self, index, value):
 587         self._check_index(index)
 588         value = create_value(value)
 589
 590         if value is None:
 591             ptr = native_bt.value_null
 592         else:
 593             ptr = value._ptr
 594
 595         status = native_bt.value_array_set(self._ptr, index, ptr)
 596         self._handle_status(status)
 597
 598     def append(self, value):
 599         value = create_value(value)
 600
 601         if value is None:
 602             ptr = native_bt.value_null
 603         else:
 604             ptr = value._ptr
 605
 606         status = native_bt.value_array_append(self._ptr, ptr)
 607         self._handle_status(status)
 608
 609     def __iadd__(self, iterable):
 610         # Python will raise a TypeError if there's anything wrong with
 611         # the iterable protocol.
 612         for elem in iterable:
 613             self.append(elem)
 614
 615         return self
 616
 617     def __str__(self):
 618         strings = []
 619
 620         for elem in self:
 621             if isinstance(elem, StringValue):
 622                 strings.append(repr(elem._value))
 623             else:
 624                 strings.append(str(elem))
 625
 626         return '[{}]'.format(', '.join(strings))
 627
 628     def insert(self, value):
 629         raise NotImplementedError
 630
 631
 632 class _MapValueKeyIterator(collections.abc.Iterator):
 633     def __init__(self, map_obj):
 634         self._map_obj = map_obj
 635         self._at = 0
 636         keys_ptr = native_bt.value_map_get_keys_private(map_obj._ptr)
 637
 638         if keys_ptr is None:
 639             raise RuntimeError('unexpected error: cannot get map value object keys')
 640
 641         self._keys = _create_from_ptr(keys_ptr)
 642
 643     def __next__(self):
 644         if self._at == len(self._map_obj):
 645             raise StopIteration
 646
 647         key = self._keys[self._at]
 648         self._at += 1
 649         return str(key)
 650
 651
 652 class MapValue(_Container, collections.abc.MutableMapping, _Value):
 653     _NAME = 'Map'
 654
 655     def __init__(self, value=None):
 656         ptr = native_bt.value_map_create()
 657         self._check_create_status(ptr)
 658         super().__init__(ptr)
 659
 660         # Python will raise a TypeError if there's anything wrong with
 661         # the iterable/mapping protocol.
 662         if value is not None:
 663             for key, elem in value.items():
 664                 self[key] = elem
 665
 666     def __eq__(self, other):
 667         return _Value.__eq__(self, other)
 668
 669     def __ne__(self, other):
 670         return _Value.__ne__(self, other)
 671
 672     def _spec_eq(self, other):
 673         try:
 674             if len(self) != len(other):
 675                 # early mismatch
 676                 return False
 677
 678             for self_key in self:
 679                 if self_key not in other:
 680                     return False
 681
 682                 self_value = self[self_key]
 683                 other_value = other[self_key]
 684
 685                 if self_value != other_value:
 686                     return False
 687
 688             return True
 689         except:
 690             return
 691
 692     def __len__(self):
 693         size = native_bt.value_map_size(self._ptr)
 694         assert(size >= 0)
 695         return size
 696
 697     def __contains__(self, key):
 698         self._check_key_type(key)
 699         return native_bt.value_map_has_key(self._ptr, key)
 700
 701     def _check_key_type(self, key):
 702         utils._check_str(key)
 703
 704     def _check_key(self, key):
 705         if key not in self:
 706             raise KeyError(key)
 707
 708     def __getitem__(self, key):
 709         self._check_key(key)
 710         ptr = native_bt.value_map_get(self._ptr, key)
 711         assert(ptr)
 712         return _create_from_ptr(ptr)
 713
 714     def __iter__(self):
 715         return _MapValueKeyIterator(self)
 716
 717     def __setitem__(self, key, value):
 718         self._check_key_type(key)
 719         value = create_value(value)
 720
 721         if value is None:
 722             ptr = native_bt.value_null
 723         else:
 724             ptr = value._ptr
 725
 726         status = native_bt.value_map_insert(self._ptr, key, ptr)
 727         self._handle_status(status)
 728
 729     def __str__(self):
 730         strings = []
 731
 732         for key, elem in self.items():
 733             if isinstance(elem, StringValue):
 734                 value = repr(elem._value)
 735             else:
 736                 value = str(elem)
 737
 738             strings.append('{}: {}'.format(repr(key), value))
 739
 740         return '{{{}}}'.format(', '.join(strings))
 741
 742
 743 _TYPE_TO_OBJ = {
 744     native_bt.VALUE_TYPE_BOOL: BoolValue,
 745     native_bt.VALUE_TYPE_INTEGER: IntegerValue,
 746     native_bt.VALUE_TYPE_FLOAT: FloatValue,
 747     native_bt.VALUE_TYPE_STRING: StringValue,
 748     native_bt.VALUE_TYPE_ARRAY: ArrayValue,
 749     native_bt.VALUE_TYPE_MAP: MapValue,
 750 }