src/bindings/python/bt2/bt2/field.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 bt2.field_class
  25 import collections.abc
  26 import functools
  27 import numbers
  28 import math
  29 import bt2
  30
  31
  32 def _create_field_from_ptr(ptr, owner_ptr, owner_get_ref, owner_put_ref):
  33     field_class_ptr = native_bt.field_borrow_class_const(ptr)
  34     utils._handle_ptr(field_class_ptr, "cannot get field object's class")
  35     typeid = native_bt.field_class_get_type(field_class_ptr)
  36     field = _TYPE_ID_TO_OBJ[typeid]._create_from_ptr_and_get_ref(
  37         ptr, owner_ptr, owner_get_ref, owner_put_ref)
  38     return field
  39
  40
  41 # Get the "effective" field of `field`.  If `field` is a variant, return the
  42 # currently selected field.  If `field` is of any other type, return `field`
  43 # directly.
  44
  45 def _get_leaf_field(field):
  46     if not isinstance(field, _VariantField):
  47         return field
  48
  49     return _get_leaf_field(field.selected_option)
  50
  51
  52 class _Field(object._UniqueObject):
  53     def __eq__(self, other):
  54         other = _get_leaf_field(other)
  55         return self._spec_eq(other)
  56
  57     @property
  58     def field_class(self):
  59         field_class_ptr = native_bt.field_borrow_class_const(self._ptr)
  60         assert field_class_ptr is not None
  61         return bt2.field_class._create_field_class_from_ptr_and_get_ref(field_class_ptr)
  62
  63     def _repr(self):
  64         raise NotImplementedError
  65
  66     def __repr__(self):
  67         return self._repr()
  68
  69
  70 @functools.total_ordering
  71 class _NumericField(_Field):
  72     @staticmethod
  73     def _extract_value(other):
  74         if isinstance(other, bool):
  75             return other
  76
  77         if isinstance(other, numbers.Integral):
  78             return int(other)
  79
  80         if isinstance(other, numbers.Real):
  81             return float(other)
  82
  83         if isinstance(other, numbers.Complex):
  84             return complex(other)
  85
  86         raise TypeError("'{}' object is not a number object".format(other.__class__.__name__))
  87
  88     def __int__(self):
  89         return int(self._value)
  90
  91     def __float__(self):
  92         return float(self._value)
  93
  94     def _repr(self):
  95         return repr(self._value)
  96
  97     def __lt__(self, other):
  98         if not isinstance(other, numbers.Number):
  99             raise TypeError('unorderable types: {}() < {}()'.format(self.__class__.__name__,
 100                                                                     other.__class__.__name__))
 101
 102         return self._value < self._extract_value(other)
 103
 104     def _spec_eq(self, other):
 105         try:
 106             return self._value == self._extract_value(other)
 107         except:
 108             return False
 109
 110     def __rmod__(self, other):
 111         return self._extract_value(other) % self._value
 112
 113     def __mod__(self, other):
 114         return self._value % self._extract_value(other)
 115
 116     def __rfloordiv__(self, other):
 117         return self._extract_value(other) // self._value
 118
 119     def __floordiv__(self, other):
 120         return self._value // self._extract_value(other)
 121
 122     def __round__(self, ndigits=None):
 123         if ndigits is None:
 124             return round(self._value)
 125         else:
 126             return round(self._value, ndigits)
 127
 128     def __ceil__(self):
 129         return math.ceil(self._value)
 130
 131     def __floor__(self):
 132         return math.floor(self._value)
 133
 134     def __trunc__(self):
 135         return int(self._value)
 136
 137     def __abs__(self):
 138         return abs(self._value)
 139
 140     def __add__(self, other):
 141         return self._value + self._extract_value(other)
 142
 143     def __radd__(self, other):
 144         return self.__add__(other)
 145
 146     def __neg__(self):
 147         return -self._value
 148
 149     def __pos__(self):
 150         return +self._value
 151
 152     def __mul__(self, other):
 153         return self._value * self._extract_value(other)
 154
 155     def __rmul__(self, other):
 156         return self.__mul__(other)
 157
 158     def __truediv__(self, other):
 159         return self._value / self._extract_value(other)
 160
 161     def __rtruediv__(self, other):
 162         return self._extract_value(other) / self._value
 163
 164     def __pow__(self, exponent):
 165         return self._value ** self._extract_value(exponent)
 166
 167     def __rpow__(self, base):
 168         return self._extract_value(base) ** self._value
 169
 170
 171 class _IntegralField(_NumericField, numbers.Integral):
 172     def __lshift__(self, other):
 173         return self._value << self._extract_value(other)
 174
 175     def __rlshift__(self, other):
 176         return self._extract_value(other) << self._value
 177
 178     def __rshift__(self, other):
 179         return self._value >> self._extract_value(other)
 180
 181     def __rrshift__(self, other):
 182         return self._extract_value(other) >> self._value
 183
 184     def __and__(self, other):
 185         return self._value & self._extract_value(other)
 186
 187     def __rand__(self, other):
 188         return self._extract_value(other) & self._value
 189
 190     def __xor__(self, other):
 191         return self._value ^ self._extract_value(other)
 192
 193     def __rxor__(self, other):
 194         return self._extract_value(other) ^ self._value
 195
 196     def __or__(self, other):
 197         return self._value | self._extract_value(other)
 198
 199     def __ror__(self, other):
 200         return self._extract_value(other) | self._value
 201
 202     def __invert__(self):
 203         return ~self._value
 204
 205
 206 class _IntegerField(_IntegralField, _Field):
 207     pass
 208
 209
 210 class _UnsignedIntegerField(_IntegerField, _Field):
 211     _NAME = 'Unsigned integer'
 212
 213     def _value_to_int(self, value):
 214         if not isinstance(value, numbers.Integral):
 215             raise TypeError('expecting an integral number object')
 216
 217         value = int(value)
 218         utils._check_uint64(value)
 219
 220         return value
 221
 222     @property
 223     def _value(self):
 224         return native_bt.field_unsigned_integer_get_value(self._ptr)
 225
 226     def _set_value(self, value):
 227         value = self._value_to_int(value)
 228         native_bt.field_unsigned_integer_set_value(self._ptr, value)
 229
 230     value = property(fset=_set_value)
 231
 232
 233 class _SignedIntegerField(_IntegerField, _Field):
 234     _NAME = 'Signed integer'
 235
 236     def _value_to_int(self, value):
 237         if not isinstance(value, numbers.Integral):
 238             raise TypeError('expecting an integral number object')
 239
 240         value = int(value)
 241         utils._check_int64(value)
 242
 243         return value
 244
 245     @property
 246     def _value(self):
 247         return native_bt.field_signed_integer_get_value(self._ptr)
 248
 249     def _set_value(self, value):
 250         value = self._value_to_int(value)
 251         native_bt.field_signed_integer_set_value(self._ptr, value)
 252
 253     value = property(fset=_set_value)
 254
 255
 256 class _RealField(_NumericField, numbers.Real):
 257     _NAME = 'Real'
 258
 259     def _value_to_float(self, value):
 260         if not isinstance(value, numbers.Real):
 261             raise TypeError("expecting a real number object")
 262
 263         return float(value)
 264
 265     @property
 266     def _value(self):
 267         return native_bt.field_real_get_value(self._ptr)
 268
 269     def _set_value(self, value):
 270         value = self._value_to_float(value)
 271         native_bt.field_real_set_value(self._ptr, value)
 272
 273     value = property(fset=_set_value)
 274
 275
 276 class _EnumerationField(_IntegerField):
 277     def _repr(self):
 278         return '{} ({})'.format(self._value, ', '.join(self.labels))
 279
 280     @property
 281     def labels(self):
 282         status, labels = self._get_mapping_labels(self._ptr)
 283         utils._handle_func_status(status,
 284                                   "cannot get label for enumeration field")
 285
 286         assert labels is not None
 287         return labels
 288
 289
 290 class _UnsignedEnumerationField(_EnumerationField, _UnsignedIntegerField):
 291     _NAME = 'Unsigned Enumeration'
 292     _get_mapping_labels = staticmethod(native_bt.field_unsigned_enumeration_get_mapping_labels)
 293
 294
 295 class _SignedEnumerationField(_EnumerationField, _SignedIntegerField):
 296     _NAME = 'Signed Enumeration'
 297     _get_mapping_labels = staticmethod(native_bt.field_signed_enumeration_get_mapping_labels)
 298
 299
 300 @functools.total_ordering
 301 class _StringField(_Field):
 302     _NAME = 'String'
 303
 304     def _value_to_str(self, value):
 305         if isinstance(value, self.__class__):
 306             value = value._value
 307
 308         if not isinstance(value, str):
 309             raise TypeError("expecting a 'str' object")
 310
 311         return value
 312
 313     @property
 314     def _value(self):
 315         return native_bt.field_string_get_value(self._ptr)
 316
 317     def _set_value(self, value):
 318         value = self._value_to_str(value)
 319         native_bt.field_string_set_value(self._ptr, value)
 320
 321     value = property(fset=_set_value)
 322
 323     def _spec_eq(self, other):
 324         try:
 325             return self._value == self._value_to_str(other)
 326         except:
 327             return False
 328
 329     def __lt__(self, other):
 330         return self._value < self._value_to_str(other)
 331
 332     def __bool__(self):
 333         return bool(self._value)
 334
 335     def _repr(self):
 336         return repr(self._value)
 337
 338     def __str__(self):
 339         return str(self._value)
 340
 341     def __getitem__(self, index):
 342         return self._value[index]
 343
 344     def __len__(self):
 345         return native_bt.field_string_get_length(self._ptr)
 346
 347     def __iadd__(self, value):
 348         value = self._value_to_str(value)
 349         status = native_bt.field_string_append(self._ptr, value)
 350         utils._handle_func_status(status,
 351                                   "cannot append to string field object's value")
 352         return self
 353
 354
 355 class _ContainerField(_Field):
 356     def __bool__(self):
 357         return len(self) != 0
 358
 359     def __len__(self):
 360         count = self._count()
 361         assert count >= 0
 362         return count
 363
 364     def __delitem__(self, index):
 365         raise NotImplementedError
 366
 367
 368 class _StructureField(_ContainerField, collections.abc.MutableMapping):
 369     _NAME = 'Structure'
 370
 371     def _count(self):
 372         return len(self.field_class)
 373
 374     def __setitem__(self, key, value):
 375         # raises if key is somehow invalid
 376         field = self[key]
 377
 378         # the field's property does the appropriate conversion or raises
 379         # the appropriate exception
 380         field.value = value
 381
 382     def __iter__(self):
 383         # same name iterator
 384         return iter(self.field_class)
 385
 386     def _spec_eq(self, other):
 387         if not isinstance(other, collections.abc.Mapping):
 388             return False
 389
 390         if len(self) != len(other):
 391             # early mismatch
 392             return False
 393
 394         for self_key in self:
 395             if self_key not in other:
 396                 return False
 397
 398             if self[self_key] != other[self_key]:
 399                 return False
 400
 401         return True
 402
 403     def _set_value(self, values):
 404         try:
 405             for key, value in values.items():
 406                 self[key].value = value
 407         except Exception:
 408             raise
 409
 410     value = property(fset=_set_value)
 411
 412     def _repr(self):
 413         items = ['{}: {}'.format(repr(k), repr(v)) for k, v in self.items()]
 414         return '{{{}}}'.format(', '.join(items))
 415
 416     def __getitem__(self, key):
 417         utils._check_str(key)
 418         field_ptr = native_bt.field_structure_borrow_member_field_by_name(self._ptr, key)
 419
 420         if field_ptr is None:
 421             raise KeyError(key)
 422
 423         return _create_field_from_ptr(field_ptr, self._owner_ptr,
 424                                       self._owner_get_ref,
 425                                       self._owner_put_ref)
 426
 427     def member_at_index(self, index):
 428         utils._check_uint64(index)
 429
 430         if index >= len(self):
 431             raise IndexError
 432
 433         field_ptr = native_bt.field_structure_borrow_member_field_by_index(self._ptr, index)
 434         assert field_ptr is not None
 435         return _create_field_from_ptr(field_ptr, self._owner_ptr,
 436                                       self._owner_get_ref,
 437                                       self._owner_put_ref)
 438
 439
 440 class _VariantField(_ContainerField, _Field):
 441     _NAME = 'Variant'
 442
 443     @property
 444     def selected_option_index(self):
 445         return native_bt.field_variant_get_selected_option_field_index(self._ptr)
 446
 447     @selected_option_index.setter
 448     def selected_option_index(self, index):
 449         native_bt.field_variant_select_option_field(self._ptr, index)
 450
 451     @property
 452     def selected_option(self):
 453         field_ptr = native_bt.field_variant_borrow_selected_option_field(self._ptr)
 454         utils._handle_ptr(field_ptr, "cannot get variant field's selected option")
 455
 456         return _create_field_from_ptr(field_ptr, self._owner_ptr,
 457                                       self._owner_get_ref,
 458                                       self._owner_put_ref)
 459
 460     def _spec_eq(self, other):
 461         return _get_leaf_field(self) == other
 462
 463     def __bool__(self):
 464         raise NotImplementedError
 465
 466     def __str__(self):
 467         return str(self.selected_option)
 468
 469     def _repr(self):
 470         return repr(self.selected_option)
 471
 472     def _set_value(self, value):
 473         self.selected_option.value = value
 474
 475     value = property(fset=_set_value)
 476
 477
 478 class _ArrayField(_ContainerField, _Field, collections.abc.MutableSequence):
 479     def _get_length(self):
 480         return native_bt.field_array_get_length(self._ptr)
 481
 482     length = property(fget=_get_length)
 483
 484     def __getitem__(self, index):
 485         if not isinstance(index, numbers.Integral):
 486             raise TypeError("'{}' is not an integral number object: invalid index".format(index.__class__.__name__))
 487
 488         index = int(index)
 489
 490         if index < 0 or index >= len(self):
 491             raise IndexError('{} field object index is out of range'.format(self._NAME))
 492
 493         field_ptr = native_bt.field_array_borrow_element_field_by_index(self._ptr, index)
 494         assert(field_ptr)
 495         return _create_field_from_ptr(field_ptr, self._owner_ptr,
 496                                       self._owner_get_ref,
 497                                       self._owner_put_ref)
 498
 499     def __setitem__(self, index, value):
 500         # raises if index is somehow invalid
 501         field = self[index]
 502
 503         if not isinstance(field, (_NumericField, _StringField)):
 504             raise TypeError('can only set the value of a number or string field')
 505
 506         # the field's property does the appropriate conversion or raises
 507         # the appropriate exception
 508         field.value = value
 509
 510     def insert(self, index, value):
 511         raise NotImplementedError
 512
 513     def _spec_eq(self, other):
 514         if not isinstance(other, collections.abc.Sequence):
 515             return False
 516
 517         if len(self) != len(other):
 518             # early mismatch
 519             return False
 520
 521         for self_elem, other_elem in zip(self, other):
 522             if self_elem != other_elem:
 523                 return False
 524
 525         return True
 526
 527     def _repr(self):
 528         return '[{}]'.format(', '.join([repr(v) for v in self]))
 529
 530
 531 class _StaticArrayField(_ArrayField, _Field):
 532     _NAME = 'Static array'
 533
 534     def _count(self):
 535         return native_bt.field_array_get_length(self._ptr)
 536
 537     def _set_value(self, values):
 538         if len(self) != len(values):
 539             raise ValueError(
 540                 'expected length of value and array field to match')
 541
 542         for index, value in enumerate(values):
 543             if value is not None:
 544                 self[index].value = value
 545
 546     value = property(fset=_set_value)
 547
 548
 549 class _DynamicArrayField(_ArrayField, _Field):
 550     _NAME = 'Dynamic array'
 551
 552     def _count(self):
 553         return self.length
 554
 555     def _set_length(self, length):
 556         utils._check_uint64(length)
 557         status = native_bt.field_dynamic_array_set_length(self._ptr, length)
 558         utils._handle_func_status(status, "cannot set dynamic array length")
 559
 560     length = property(fget=_ArrayField._get_length, fset=_set_length)
 561
 562     def _set_value(self, values):
 563         if len(values) != self.length:
 564             self.length = len(values)
 565
 566         for index, value in enumerate(values):
 567             if value is not None:
 568                 self[index].value = value
 569
 570     value = property(fset=_set_value)
 571
 572
 573 _TYPE_ID_TO_OBJ = {
 574     native_bt.FIELD_CLASS_TYPE_UNSIGNED_INTEGER: _UnsignedIntegerField,
 575     native_bt.FIELD_CLASS_TYPE_SIGNED_INTEGER: _SignedIntegerField,
 576     native_bt.FIELD_CLASS_TYPE_REAL: _RealField,
 577     native_bt.FIELD_CLASS_TYPE_UNSIGNED_ENUMERATION: _UnsignedEnumerationField,
 578     native_bt.FIELD_CLASS_TYPE_SIGNED_ENUMERATION: _SignedEnumerationField,
 579     native_bt.FIELD_CLASS_TYPE_STRING: _StringField,
 580     native_bt.FIELD_CLASS_TYPE_STRUCTURE: _StructureField,
 581     native_bt.FIELD_CLASS_TYPE_STATIC_ARRAY: _StaticArrayField,
 582     native_bt.FIELD_CLASS_TYPE_DYNAMIC_ARRAY: _DynamicArrayField,
 583     native_bt.FIELD_CLASS_TYPE_VARIANT: _VariantField,
 584 }