| 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.notification_iterator |
| 25 | import collections.abc |
| 26 | import bt2 |
| 27 | |
| 28 | |
| 29 | # This class wraps a component class pointer. This component class could |
| 30 | # have been created by Python code, but since we only have the pointer, |
| 31 | # we can only wrap it in a generic way and lose the original Python |
| 32 | # class. |
| 33 | class _GenericComponentClass(object._Object): |
| 34 | @property |
| 35 | def name(self): |
| 36 | return native_bt.component_class_get_name(self._ptr) |
| 37 | |
| 38 | @property |
| 39 | def description(self): |
| 40 | return native_bt.component_class_get_description(self._ptr) |
| 41 | |
| 42 | def __call__(self, params=None, name=None): |
| 43 | params = bt2.create_value(params) |
| 44 | comp_ptr = native_bt.component_create_with_init_method_data(self._ptr, |
| 45 | name, |
| 46 | params._ptr, |
| 47 | None) |
| 48 | |
| 49 | if comp_ptr is None: |
| 50 | raise bt2.CreationError('cannot create component object') |
| 51 | |
| 52 | return _create_generic_component_from_ptr(comp_ptr) |
| 53 | |
| 54 | |
| 55 | class _GenericSourceComponentClass(_GenericComponentClass): |
| 56 | pass |
| 57 | |
| 58 | |
| 59 | class _GenericFilterComponentClass(_GenericComponentClass): |
| 60 | pass |
| 61 | |
| 62 | |
| 63 | class _GenericSinkComponentClass(_GenericComponentClass): |
| 64 | pass |
| 65 | |
| 66 | |
| 67 | # This class holds the methods which are common to both generic |
| 68 | # component objects and Python user component objects. They use the |
| 69 | # internal native _ptr, however it was set, to call native API |
| 70 | # functions. |
| 71 | class _CommonComponentMethods: |
| 72 | @property |
| 73 | def name(self): |
| 74 | return native_bt.component_get_name(self._ptr) |
| 75 | |
| 76 | @property |
| 77 | def component_class(self): |
| 78 | cc_ptr = native_bt.component_get_class(self._ptr) |
| 79 | utils._handle_ptr(cc_ptr, "cannot get component object's class object") |
| 80 | return _create_generic_component_class_from_ptr(cc_ptr) |
| 81 | |
| 82 | def _handle_status(self, status, gen_error_msg): |
| 83 | if status == native_bt.COMPONENT_STATUS_END: |
| 84 | raise bt2.Stop |
| 85 | elif status == native_bt.COMPONENT_STATUS_AGAIN: |
| 86 | raise bt2.TryAgain |
| 87 | elif status == native_bt.COMPONENT_STATUS_UNSUPPORTED: |
| 88 | raise bt2.UnsupportedFeature |
| 89 | elif status < 0: |
| 90 | raise bt2.Error(gen_error_msg) |
| 91 | |
| 92 | |
| 93 | class _CommonSourceComponentMethods(_CommonComponentMethods): |
| 94 | def create_notification_iterator(self): |
| 95 | iter_ptr = native_bt.component_source_create_notification_iterator_with_init_method_data(self._ptr, None) |
| 96 | |
| 97 | if iter_ptr is None: |
| 98 | raise bt2.CreationError('cannot create notification iterator object') |
| 99 | |
| 100 | return bt2.notification_iterator._GenericNotificationIterator._create_from_ptr(iter_ptr) |
| 101 | |
| 102 | |
| 103 | class _CommonFilterComponentMethods(_CommonComponentMethods): |
| 104 | def create_notification_iterator(self): |
| 105 | iter_ptr = native_bt.component_filter_create_notification_iterator_with_init_method_data(self._ptr, None) |
| 106 | |
| 107 | if iter_ptr is None: |
| 108 | raise bt2.CreationError('cannot create notification iterator object') |
| 109 | |
| 110 | return bt2.notification_iterator._GenericNotificationIterator._create_from_ptr(iter_ptr) |
| 111 | |
| 112 | def add_notification_iterator(self, notif_iter): |
| 113 | utils._check_type(notif_iter, bt2.notification_iterator._GenericNotificationIteratorMethods) |
| 114 | status = native_bt.component_filter_add_iterator(self._ptr, notif_iter._ptr) |
| 115 | self._handle_status(status, 'unexpected error: cannot add notification iterator to filter component object') |
| 116 | |
| 117 | |
| 118 | class _CommonSinkComponentMethods(_CommonComponentMethods): |
| 119 | def add_notification_iterator(self, notif_iter): |
| 120 | utils._check_type(notif_iter, bt2.notification_iterator._GenericNotificationIteratorMethods) |
| 121 | status = native_bt.component_sink_add_iterator(self._ptr, notif_iter._ptr) |
| 122 | self._handle_status(status, 'unexpected error: cannot add notification iterator to sink component object') |
| 123 | |
| 124 | def consume(self): |
| 125 | status = native_bt.component_sink_consume(self._ptr) |
| 126 | self._handle_status(status, 'unexpected error: cannot consume sink component object') |
| 127 | |
| 128 | |
| 129 | # This is analogous to _GenericSourceComponentClass, but for source |
| 130 | # component objects. |
| 131 | class _GenericSourceComponent(object._Object, _CommonSourceComponentMethods): |
| 132 | pass |
| 133 | |
| 134 | |
| 135 | # This is analogous to _GenericFilterComponentClass, but for filter |
| 136 | # component objects. |
| 137 | class _GenericFilterComponent(object._Object, _CommonFilterComponentMethods): |
| 138 | pass |
| 139 | |
| 140 | |
| 141 | # This is analogous to _GenericSinkComponentClass, but for sink |
| 142 | # component objects. |
| 143 | class _GenericSinkComponent(object._Object, _CommonSinkComponentMethods): |
| 144 | pass |
| 145 | |
| 146 | |
| 147 | _COMP_CLS_TYPE_TO_GENERIC_COMP_CLS = { |
| 148 | native_bt.COMPONENT_CLASS_TYPE_SOURCE: _GenericSourceComponent, |
| 149 | native_bt.COMPONENT_CLASS_TYPE_FILTER: _GenericFilterComponent, |
| 150 | native_bt.COMPONENT_CLASS_TYPE_SINK: _GenericSinkComponent, |
| 151 | } |
| 152 | |
| 153 | |
| 154 | _COMP_CLS_TYPE_TO_GENERIC_COMP_CLS_CLS = { |
| 155 | native_bt.COMPONENT_CLASS_TYPE_SOURCE: _GenericSourceComponentClass, |
| 156 | native_bt.COMPONENT_CLASS_TYPE_FILTER: _GenericFilterComponentClass, |
| 157 | native_bt.COMPONENT_CLASS_TYPE_SINK: _GenericSinkComponentClass, |
| 158 | } |
| 159 | |
| 160 | |
| 161 | def _create_generic_component_from_ptr(ptr): |
| 162 | comp_cls_type = native_bt.component_get_class_type(ptr) |
| 163 | return _COMP_CLS_TYPE_TO_GENERIC_COMP_CLS[comp_cls_type]._create_from_ptr(ptr) |
| 164 | |
| 165 | |
| 166 | def _create_generic_component_class_from_ptr(ptr): |
| 167 | comp_cls_type = native_bt.component_class_get_type(ptr) |
| 168 | return _COMP_CLS_TYPE_TO_GENERIC_COMP_CLS_CLS[comp_cls_type]._create_from_ptr(ptr) |
| 169 | |
| 170 | |
| 171 | # Metaclass for component classes defined by Python code. |
| 172 | # |
| 173 | # The Python user can create a standard Python class which inherits one |
| 174 | # of the three base classes (UserSourceComponent, UserFilterComponent, |
| 175 | # or UserSinkComponent). Those base classes set this class |
| 176 | # (_UserComponentType) as their metaclass. |
| 177 | # |
| 178 | # Once the body of a user-defined component class is executed, this |
| 179 | # metaclass is used to create and initialize the class. The metaclass |
| 180 | # creates a native BT component class of the corresponding type and |
| 181 | # associates it with this user-defined class. The metaclass also defines |
| 182 | # class methods like the `name` and `description` properties to match |
| 183 | # the _GenericComponentClass interface. |
| 184 | # |
| 185 | # The component class name which is used is either: |
| 186 | # |
| 187 | # * The `name` parameter of the class: |
| 188 | # |
| 189 | # class MySink(bt2.SinkComponent, name='my-custom-sink'): |
| 190 | # ... |
| 191 | # |
| 192 | # * If the `name` class parameter is not used: the name of the class |
| 193 | # itself (`MySink` in the example above). |
| 194 | # |
| 195 | # The component class description which is used is the user-defined |
| 196 | # class's docstring: |
| 197 | # |
| 198 | # class MySink(bt2.SinkComponent): |
| 199 | # 'Description goes here' |
| 200 | # ... |
| 201 | # |
| 202 | # A user-defined Python component class can have an __init__() method |
| 203 | # which must at least accept the `params` and `name` arguments: |
| 204 | # |
| 205 | # def __init__(self, params, name, something_else): |
| 206 | # ... |
| 207 | # |
| 208 | # The user-defined component class can also have a _destroy() method |
| 209 | # (do NOT use __del__()) to be notified when the component object is |
| 210 | # (really) destroyed. |
| 211 | # |
| 212 | # User-defined source and filter component classes must use the |
| 213 | # `notification_iterator_class` class parameter to specify the |
| 214 | # notification iterator class to use for this component class: |
| 215 | # |
| 216 | # class MyNotificationIterator(bt2.UserNotificationIterator): |
| 217 | # ... |
| 218 | # |
| 219 | # class MySource(bt2.UserSourceComponent, |
| 220 | # notification_iterator_class=MyNotificationIterator): |
| 221 | # ... |
| 222 | # |
| 223 | # This notification iterator class must inherit |
| 224 | # bt2.UserNotificationIterator, and it must define the _get() and |
| 225 | # _next() methods. The notification iterator class can also define an |
| 226 | # __init__() method: this method has access to the original Python |
| 227 | # component object which was used to create it as the `component` |
| 228 | # property. The notification iterator class can also define a _destroy() |
| 229 | # method (again, do NOT use __del__()): this is called when the |
| 230 | # notification iterator is (really) destroyed. |
| 231 | # |
| 232 | # When the user-defined class is destroyed, this metaclass's __del__() |
| 233 | # method is called: the native BT component class pointer is put (not |
| 234 | # needed anymore, at least not by any Python code since all references |
| 235 | # are dropped for __del__() to be called). |
| 236 | class _UserComponentType(type): |
| 237 | # __new__() is used to catch custom class parameters |
| 238 | def __new__(meta_cls, class_name, bases, attrs, **kwargs): |
| 239 | return super().__new__(meta_cls, class_name, bases, attrs) |
| 240 | |
| 241 | def __init__(cls, class_name, bases, namespace, **kwargs): |
| 242 | super().__init__(class_name, bases, namespace) |
| 243 | |
| 244 | # skip our own bases; they are never directly instantiated by the user |
| 245 | if class_name in ('_UserComponent', 'UserSourceComponent', 'UserFilterComponent', 'UserSinkComponent'): |
| 246 | return |
| 247 | |
| 248 | comp_cls_name = kwargs.get('name', class_name) |
| 249 | comp_cls_descr = getattr(cls, '__doc__', None) |
| 250 | iter_cls = kwargs.get('notification_iterator_class') |
| 251 | |
| 252 | if UserSourceComponent in bases: |
| 253 | _UserComponentType._set_iterator_class(cls, iter_cls) |
| 254 | has_seek_time = _UserComponentType._has_seek_to_time_method(cls._iter_cls) |
| 255 | cc_ptr = native_bt.py3_component_class_source_create(cls, |
| 256 | comp_cls_name, |
| 257 | comp_cls_descr, |
| 258 | has_seek_time) |
| 259 | elif UserFilterComponent in bases: |
| 260 | _UserComponentType._set_iterator_class(cls, iter_cls) |
| 261 | has_seek_time = _UserComponentType._has_seek_to_time_method(cls._iter_cls) |
| 262 | cc_ptr = native_bt.py3_component_class_filter_create(cls, |
| 263 | comp_cls_name, |
| 264 | comp_cls_descr, |
| 265 | has_seek_time) |
| 266 | elif UserSinkComponent in bases: |
| 267 | if not hasattr(cls, '_consume'): |
| 268 | raise bt2.IncompleteUserClassError("cannot create component class '{}': missing a _consume() method".format(class_name)) |
| 269 | |
| 270 | cc_ptr = native_bt.py3_component_class_sink_create(cls, |
| 271 | comp_cls_name, |
| 272 | comp_cls_descr) |
| 273 | else: |
| 274 | raise bt2.IncompleteUserClassError("cannot find a known component class base in the bases of '{}'".format(class_name)) |
| 275 | |
| 276 | if cc_ptr is None: |
| 277 | raise bt2.CreationError("cannot create component class '{}'".format(class_name)) |
| 278 | |
| 279 | cls._cc_ptr = cc_ptr |
| 280 | |
| 281 | def __call__(cls, *args, **kwargs): |
| 282 | # create instance |
| 283 | self = cls.__new__(cls) |
| 284 | |
| 285 | # assign native component pointer received from caller |
| 286 | self._ptr = kwargs.get('__comp_ptr') |
| 287 | name = kwargs.get('name') |
| 288 | |
| 289 | if self._ptr is None: |
| 290 | # called from Python code |
| 291 | self._belongs_to_native_component = False |
| 292 | |
| 293 | # py3_component_create() will call self.__init__() with the |
| 294 | # desired arguments and keyword arguments. This is needed |
| 295 | # because functions such as |
| 296 | # bt_component_sink_set_minimum_input_count() can only be |
| 297 | # called _during_ the bt_component_create() call (in |
| 298 | # Python words: during self.__init__()). |
| 299 | # |
| 300 | # The arguments and keyword arguments to use for |
| 301 | # self.__init__() are put in the object itself to find them |
| 302 | # from the bt_component_create() function. |
| 303 | self._init_args = args |
| 304 | self._init_kwargs = kwargs |
| 305 | native_bt.py3_component_create(cls._cc_ptr, self, name) |
| 306 | |
| 307 | # At this point, self._ptr should be set to non-None. If |
| 308 | # it's not, an error occured during the |
| 309 | # native_bt.py3_component_create() call. We consider this a |
| 310 | # creation error. |
| 311 | if self._ptr is None: |
| 312 | raise bt2.CreationError("cannot create component object from component class '{}'".format(cls.__name__)) |
| 313 | else: |
| 314 | # Called from non-Python code (within |
| 315 | # bt_component_create()): call __init__() here, after |
| 316 | # removing the __comp_ptr keyword argument which is just for |
| 317 | # this __call__() method. |
| 318 | self._belongs_to_native_component = True |
| 319 | del kwargs['__comp_ptr'] |
| 320 | |
| 321 | # inject `name` into the keyword arguments |
| 322 | kwargs['name'] = self.name |
| 323 | self.__init__(*args, **kwargs) |
| 324 | |
| 325 | return self |
| 326 | |
| 327 | @staticmethod |
| 328 | def _has_seek_to_time_method(iter_cls): |
| 329 | return hasattr(iter_cls, '_seek_to_time') |
| 330 | |
| 331 | @staticmethod |
| 332 | def _set_iterator_class(cls, iter_cls): |
| 333 | if iter_cls is None: |
| 334 | raise bt2.IncompleteUserClassError("cannot create component class '{}': missing notification iterator class".format(cls.__name__)) |
| 335 | |
| 336 | if not issubclass(iter_cls, bt2.notification_iterator.UserNotificationIterator): |
| 337 | raise bt2.IncompleteUserClassError("cannot create component class '{}': notification iterator class does not inherit bt2.UserNotificationIterator".format(cls.__name__)) |
| 338 | |
| 339 | if not hasattr(iter_cls, '_get'): |
| 340 | raise bt2.IncompleteUserClassError("cannot create component class '{}': notification iterator class is missing a _get() method".format(cls.__name__)) |
| 341 | |
| 342 | if not hasattr(iter_cls, '_next'): |
| 343 | raise bt2.IncompleteUserClassError("cannot create component class '{}': notification iterator class is missing a _next() method".format(cls.__name__)) |
| 344 | |
| 345 | cls._iter_cls = iter_cls |
| 346 | |
| 347 | @property |
| 348 | def name(cls): |
| 349 | return native_bt.component_class_get_name(cls._cc_ptr) |
| 350 | |
| 351 | @property |
| 352 | def description(cls): |
| 353 | return native_bt.component_class_get_description(cls._cc_ptr) |
| 354 | |
| 355 | @property |
| 356 | def addr(cls): |
| 357 | return int(cls._cc_ptr) |
| 358 | |
| 359 | def __del__(cls): |
| 360 | if hasattr(cls, '_cc_ptr'): |
| 361 | native_bt.put(cls._cc_ptr) |
| 362 | |
| 363 | |
| 364 | class _ComponentInputNotificationIterators(collections.abc.Sequence): |
| 365 | def __init__(self, comp, count_func, get_func): |
| 366 | self._comp = comp |
| 367 | self._count_func = count_func |
| 368 | self._get_func = get_func |
| 369 | |
| 370 | def __len__(self): |
| 371 | status, count = self._count_func(self._comp._ptr) |
| 372 | utils._handle_ret(status, "cannot get component object's input notification iterator count") |
| 373 | return count |
| 374 | |
| 375 | def __getitem__(self, index): |
| 376 | utils._check_uint64(index) |
| 377 | |
| 378 | if index >= len(self): |
| 379 | raise IndexError |
| 380 | |
| 381 | notif_iter_ptr = self._get_func(self._comp._ptr, index) |
| 382 | utils._handle_ptr(notif_iter_ptr, "cannot get component object's input notification iterator") |
| 383 | return bt2.notification_iterator._GenericNotificationIterator._create_from_ptr(notif_iter_ptr) |
| 384 | |
| 385 | |
| 386 | class _UserComponent(metaclass=_UserComponentType): |
| 387 | @property |
| 388 | def addr(self): |
| 389 | return int(self._ptr) |
| 390 | |
| 391 | def __init__(self, *args, **kwargs): |
| 392 | pass |
| 393 | |
| 394 | def _destroy(self): |
| 395 | pass |
| 396 | |
| 397 | def __del__(self): |
| 398 | if not self._belongs_to_native_component: |
| 399 | self._belongs_to_native_component = True |
| 400 | native_bt.py3_component_on_del(self) |
| 401 | native_bt.put(self._ptr) |
| 402 | |
| 403 | |
| 404 | class UserSourceComponent(_UserComponent, _CommonSourceComponentMethods): |
| 405 | pass |
| 406 | |
| 407 | |
| 408 | class UserFilterComponent(_UserComponent, _CommonFilterComponentMethods): |
| 409 | def _set_minimum_input_notification_iterator_count(self, count): |
| 410 | utils._check_uint64(count) |
| 411 | status = native_bt.component_filter_set_minimum_input_count(self._ptr, count) |
| 412 | self._handle_status(status, "unexpected error: cannot set filter component object's minimum input notification iterator count") |
| 413 | |
| 414 | _minimum_input_notification_iterator_count = property(fset=_set_minimum_input_notification_iterator_count) |
| 415 | |
| 416 | def _set_maximum_input_notification_iterator_count(self, count): |
| 417 | utils._check_uint64(count) |
| 418 | status = native_bt.component_filter_set_maximum_input_count(self._ptr, count) |
| 419 | self._handle_status(status, "unexpected error: cannot set filter component object's maximum input notification iterator count") |
| 420 | |
| 421 | _maximum_input_notification_iterator_count = property(fset=_set_maximum_input_notification_iterator_count) |
| 422 | |
| 423 | @property |
| 424 | def _input_notification_iterators(self): |
| 425 | return _ComponentInputNotificationIterators(self, |
| 426 | native_bt.component_filter_get_input_count, |
| 427 | native_bt.component_filter_get_input_iterator_private) |
| 428 | |
| 429 | def _add_iterator_from_bt(self, notif_iter_ptr): |
| 430 | notif_iter = bt2.notification_iterator._GenericNotificationIterator._create_from_ptr(notif_iter_ptr) |
| 431 | self._add_notification_iterator(notif_iter) |
| 432 | |
| 433 | def _add_notification_iterator(self, notif_iter): |
| 434 | pass |
| 435 | |
| 436 | |
| 437 | class UserSinkComponent(_UserComponent, _CommonSinkComponentMethods): |
| 438 | def _set_minimum_input_notification_iterator_count(self, count): |
| 439 | utils._check_uint64(count) |
| 440 | status = native_bt.component_sink_set_minimum_input_count(self._ptr, count) |
| 441 | self._handle_status(status, "unexpected error: cannot set sink component object's minimum input notification iterator count") |
| 442 | |
| 443 | _minimum_input_notification_iterator_count = property(fset=_set_minimum_input_notification_iterator_count) |
| 444 | |
| 445 | def _set_maximum_input_notification_iterator_count(self, count): |
| 446 | utils._check_uint64(count) |
| 447 | status = native_bt.component_sink_set_maximum_input_count(self._ptr, count) |
| 448 | self._handle_status(status, "unexpected error: cannot set sink component object's maximum input notification iterator count") |
| 449 | |
| 450 | _maximum_input_notification_iterator_count = property(fset=_set_maximum_input_notification_iterator_count) |
| 451 | |
| 452 | @property |
| 453 | def _input_notification_iterators(self): |
| 454 | return _ComponentInputNotificationIterators(self, |
| 455 | native_bt.component_sink_get_input_count, |
| 456 | native_bt.component_sink_get_input_iterator_private) |
| 457 | |
| 458 | def _add_iterator_from_bt(self, notif_iter_ptr): |
| 459 | notif_iter = bt2.notification_iterator._GenericNotificationIterator._create_from_ptr(notif_iter_ptr) |
| 460 | self._add_notification_iterator(notif_iter) |
| 461 | |
| 462 | def _add_notification_iterator(self, notif_iter): |
| 463 | pass |