src/bindings/python/bt2/bt2/native_bt_component_class.i

   1 /*
   2  * The MIT License (MIT)
   3  *
   4  * Copyright (c) 2017 Philippe Proulx <pproulx@efficios.com>
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24
  25 %include <babeltrace2/graph/component-class.h>
  26 %include <babeltrace2/graph/component-class-const.h>
  27 %include <babeltrace2/graph/component-class-source-const.h>
  28 %include <babeltrace2/graph/component-class-source.h>
  29 %include <babeltrace2/graph/component-class-filter-const.h>
  30 %include <babeltrace2/graph/component-class-filter.h>
  31 %include <babeltrace2/graph/component-class-sink-const.h>
  32 %include <babeltrace2/graph/component-class-sink.h>
  33 %include <babeltrace2/graph/self-component-class-source.h>
  34 %include <babeltrace2/graph/self-component-class-filter.h>
  35 %include <babeltrace2/graph/self-component-class-sink.h>
  36
  37 %{
  38 /*
  39  * This hash table associates a BT component class object address to a
  40  * user-defined Python class (PyObject *). The keys and values are NOT
  41  * owned by this hash table. The Python class objects are owned by the
  42  * Python module, which should not be unloaded until it is not possible
  43  * to create a user Python component anyway.
  44  *
  45  * This hash table is written to when a user-defined Python component
  46  * class is created by one of the bt_bt2_component_class_*_create()
  47  * functions.
  48  *
  49  * This function is read from when a user calls bt_component_create()
  50  * with a component class pointer created by one of the functions above.
  51  * In this case, the original Python class needs to be found to
  52  * instantiate it and associate the created Python component object with
  53  * a BT component object instance.
  54  */
  55
  56 static GHashTable *bt_cc_ptr_to_py_cls;
  57
  58 static
  59 void register_cc_ptr_to_py_cls(struct bt_component_class *bt_cc,
  60                 PyObject *py_cls)
  61 {
  62         if (!bt_cc_ptr_to_py_cls) {
  63                 /*
  64                  * Lazy-initializing this GHashTable because GLib
  65                  * might not be initialized yet and it needs to be
  66                  * before we call g_hash_table_new()
  67                  */
  68                 BT_LOGD_STR("Creating native component class to Python component class hash table.");
  69                 bt_cc_ptr_to_py_cls = g_hash_table_new(g_direct_hash, g_direct_equal);
  70                 BT_ASSERT(bt_cc_ptr_to_py_cls);
  71         }
  72
  73         g_hash_table_insert(bt_cc_ptr_to_py_cls, (gpointer) bt_cc,
  74                 (gpointer) py_cls);
  75 }
  76
  77 static
  78 PyObject *lookup_cc_ptr_to_py_cls(const bt_component_class *bt_cc)
  79 {
  80         if (!bt_cc_ptr_to_py_cls) {
  81                 BT_LOGW("Cannot look up Python component class because hash table is NULL: "
  82                         "comp-cls-addr=%p", bt_cc);
  83                 return NULL;
  84         }
  85
  86         return (PyObject *) g_hash_table_lookup(bt_cc_ptr_to_py_cls,
  87                 (gconstpointer) bt_cc);
  88 }
  89
  90
  91 /*
  92  * Useful Python objects.
  93  */
  94
  95 static PyObject *py_mod_bt2 = NULL;
  96 static PyObject *py_mod_bt2_exc_error_type = NULL;
  97 static PyObject *py_mod_bt2_exc_memory_error = NULL;
  98 static PyObject *py_mod_bt2_exc_try_again_type = NULL;
  99 static PyObject *py_mod_bt2_exc_stop_type = NULL;
 100 static PyObject *py_mod_bt2_exc_msg_iter_canceled_type = NULL;
 101 static PyObject *py_mod_bt2_exc_invalid_object_type = NULL;
 102 static PyObject *py_mod_bt2_exc_invalid_params_type = NULL;
 103
 104 static
 105 void bt_bt2_cc_init_from_bt2(void)
 106 {
 107         /*
 108          * This is called once the bt2 package is loaded.
 109          *
 110          * Those modules and functions are needed while the package is
 111          * used. Loading them here is safe because we know the bt2
 112          * package is imported, and we know that the user cannot use the
 113          * code here without importing bt2 first.
 114          */
 115         py_mod_bt2 = PyImport_ImportModule("bt2");
 116         BT_ASSERT(py_mod_bt2);
 117         py_mod_bt2_exc_error_type =
 118                 PyObject_GetAttrString(py_mod_bt2, "_Error");
 119         BT_ASSERT(py_mod_bt2_exc_error_type);
 120         py_mod_bt2_exc_memory_error =
 121                 PyObject_GetAttrString(py_mod_bt2, "_MemoryError");
 122         BT_ASSERT(py_mod_bt2_exc_memory_error);
 123         py_mod_bt2_exc_try_again_type =
 124                 PyObject_GetAttrString(py_mod_bt2, "TryAgain");
 125         BT_ASSERT(py_mod_bt2_exc_try_again_type);
 126         py_mod_bt2_exc_stop_type =
 127                 PyObject_GetAttrString(py_mod_bt2, "Stop");
 128         BT_ASSERT(py_mod_bt2_exc_stop_type);
 129         py_mod_bt2_exc_invalid_object_type =
 130                 PyObject_GetAttrString(py_mod_bt2, "InvalidObject");
 131         BT_ASSERT(py_mod_bt2_exc_invalid_object_type);
 132         py_mod_bt2_exc_invalid_params_type =
 133                 PyObject_GetAttrString(py_mod_bt2, "InvalidParams");
 134         BT_ASSERT(py_mod_bt2_exc_invalid_params_type);
 135 }
 136
 137 static
 138 void bt_bt2_cc_exit_handler(void)
 139 {
 140         /*
 141          * This is an exit handler (set by the bt2 package).
 142          *
 143          * We only give back the references that we took in
 144          * bt_bt2_cc_init_from_bt2() here. The global variables continue
 145          * to exist for the code of this file, but they are now borrowed
 146          * references. If this code is executed, it means that somehow
 147          * the modules are still loaded, so it should be safe to use
 148          * them even without a strong reference.
 149          *
 150          * We cannot do this in the library's destructor because it
 151          * gets executed once Python is already finalized.
 152          */
 153         Py_XDECREF(py_mod_bt2);
 154         Py_XDECREF(py_mod_bt2_exc_error_type);
 155         Py_XDECREF(py_mod_bt2_exc_try_again_type);
 156         Py_XDECREF(py_mod_bt2_exc_stop_type);
 157         Py_XDECREF(py_mod_bt2_exc_msg_iter_canceled_type);
 158         Py_XDECREF(py_mod_bt2_exc_invalid_object_type);
 159         Py_XDECREF(py_mod_bt2_exc_invalid_params_type);
 160 }
 161
 162
 163 /* Library destructor */
 164
 165 __attribute__((destructor))
 166 static
 167 void native_comp_class_dtor(void) {
 168         /* Destroy component class association hash table */
 169         if (bt_cc_ptr_to_py_cls) {
 170                 BT_LOGD_STR("Destroying native component class to Python component class hash table.");
 171                 g_hash_table_destroy(bt_cc_ptr_to_py_cls);
 172         }
 173 }
 174
 175 static
 176 void restore_current_thread_error_and_append_exception_chain_recursive(
 177                 PyObject *py_exc_value,
 178                 bt_self_component_class *self_component_class,
 179                 bt_self_component *self_component,
 180                 bt_self_message_iterator *self_message_iterator,
 181                 const char *module_name)
 182 {
 183         PyObject *py_exc_cause_value;
 184         PyObject *py_exc_type = NULL;
 185         PyObject *py_exc_tb = NULL;
 186         GString *gstr = NULL;
 187
 188         /* If this exception has a cause, handle that one first. */
 189         py_exc_cause_value = PyException_GetCause(py_exc_value);
 190         if (py_exc_cause_value) {
 191                 restore_current_thread_error_and_append_exception_chain_recursive(
 192                         py_exc_cause_value, self_component_class,
 193                         self_component, self_message_iterator, module_name);
 194         }
 195
 196         /*
 197          * If the raised exception is a bt2._Error, restore the wrapped error.
 198          */
 199         if (PyErr_GivenExceptionMatches(py_exc_value, py_mod_bt2_exc_error_type)) {
 200                 PyObject *py_error_swig_ptr;
 201                 const bt_error *error;
 202                 int ret;
 203
 204                 /*
 205                  * We never raise a bt2._Error with a cause: it should be the
 206                  * end of the chain.
 207                  */
 208                 BT_ASSERT(!py_exc_cause_value);
 209
 210                 /*
 211                  * We steal the error object from the exception, to move
 212                  * it back as the current thread's error.
 213                  */
 214                 py_error_swig_ptr = PyObject_GetAttrString(py_exc_value, "_ptr");
 215                 BT_ASSERT(py_error_swig_ptr);
 216
 217                 ret = PyObject_SetAttrString(py_exc_value, "_ptr", Py_None);
 218                 BT_ASSERT(ret == 0);
 219
 220                 ret = SWIG_ConvertPtr(py_error_swig_ptr, (void **) &error,
 221                         SWIGTYPE_p_bt_error, 0);
 222                 BT_ASSERT(ret == 0);
 223
 224                 BT_CURRENT_THREAD_MOVE_ERROR_AND_RESET(error);
 225
 226                 Py_DECREF(py_error_swig_ptr);
 227         }
 228
 229         py_exc_type = PyObject_Type(py_exc_value);
 230         py_exc_tb = PyException_GetTraceback(py_exc_value);
 231
 232         gstr = bt_py_common_format_exception(py_exc_type, py_exc_value,
 233                         py_exc_tb, BT_LOG_OUTPUT_LEVEL, false);
 234         if (!gstr) {
 235                 /* bt_py_common_format_exception has already warned. */
 236                 goto end;
 237         }
 238
 239         if (self_component_class) {
 240                 BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_COMPONENT_CLASS(
 241                         self_component_class, "%s", gstr->str);
 242         } else if (self_component) {
 243                 BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_COMPONENT(
 244                         self_component, "%s", gstr->str);
 245         } else if (self_message_iterator) {
 246                 BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_MESSAGE_ITERATOR(
 247                         self_message_iterator, "%s", gstr->str);
 248         } else {
 249                 BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_UNKNOWN(
 250                         module_name, "%s", gstr->str);
 251         }
 252
 253 end:
 254         if (gstr) {
 255                 g_string_free(gstr, TRUE);
 256         }
 257
 258         Py_XDECREF(py_exc_cause_value);
 259         Py_XDECREF(py_exc_type);
 260         Py_XDECREF(py_exc_tb);
 261 }
 262
 263 /*
 264  * If you have the following code:
 265  *
 266  * try:
 267  *     try:
 268  *         something_that_raises_bt2_error()
 269  *     except bt2._Error as e1:
 270  *         raise ValueError from e1
 271  * except ValueError as e2:
 272  *     raise TypeError from e2
 273  *
 274  * We will have the following exception chain:
 275  *
 276  *     TypeError -> ValueError -> bt2._Error
 277  *
 278  * Where the TypeError is the current exception (obtained from PyErr_Fetch).
 279  *
 280  * The bt2._Error contains a `struct bt_error *` that used to be the current
 281  * thread's error, at the moment the exception was raised.
 282  *
 283  * This function gets to the bt2._Error and restores the wrapped
 284  * `struct bt_error *` as the current thread's error.
 285  *
 286  * Then, for each exception in the chain, starting with the oldest one, it adds
 287  * an error cause to the current thread's error.
 288  */
 289 static
 290 void restore_bt_error_and_append_current_exception_chain(
 291                 bt_self_component_class *self_component_class,
 292                 bt_self_component *self_component,
 293                 bt_self_message_iterator *self_message_iterator,
 294                 const char *module_name)
 295 {
 296         BT_ASSERT(PyErr_Occurred());
 297
 298         /* Used to access and restore the current exception. */
 299         PyObject *py_exc_type;
 300         PyObject *py_exc_value;
 301         PyObject *py_exc_tb;
 302
 303         /* Fetch and normalize the Python exception. */
 304         PyErr_Fetch(&py_exc_type, &py_exc_value, &py_exc_tb);
 305         PyErr_NormalizeException(&py_exc_type, &py_exc_value, &py_exc_tb);
 306         BT_ASSERT(py_exc_type);
 307         BT_ASSERT(py_exc_value);
 308         BT_ASSERT(py_exc_tb);
 309
 310         /*
 311          * Set the exception's traceback so it's possible to get it using
 312          * PyException_GetTraceback in
 313          * restore_current_thread_error_and_append_exception_chain_recursive.
 314          */
 315         PyException_SetTraceback(py_exc_value, py_exc_tb);
 316
 317         restore_current_thread_error_and_append_exception_chain_recursive(py_exc_value,
 318                 self_component_class, self_component, self_message_iterator,
 319                 module_name);
 320
 321         PyErr_Restore(py_exc_type, py_exc_value, py_exc_tb);
 322 }
 323
 324 static inline
 325 void log_exception_and_maybe_append_error(int log_level,
 326                 bool append_error,
 327                 bt_self_component_class *self_component_class,
 328                 bt_self_component *self_component,
 329                 bt_self_message_iterator *self_message_iterator,
 330                 const char *module_name)
 331 {
 332         GString *gstr;
 333
 334         BT_ASSERT(PyErr_Occurred());
 335         gstr = bt_py_common_format_current_exception(BT_LOG_OUTPUT_LEVEL);
 336         if (!gstr) {
 337                 /* bt_py_common_format_current_exception() logs errors */
 338                 goto end;
 339         }
 340
 341         BT_LOG_WRITE(log_level, BT_LOG_TAG, "%s", gstr->str);
 342
 343         if (append_error) {
 344                 restore_bt_error_and_append_current_exception_chain(
 345                         self_component_class, self_component,
 346                         self_message_iterator, module_name);
 347
 348         }
 349
 350 end:
 351         if (gstr) {
 352                 g_string_free(gstr, TRUE);
 353         }
 354 }
 355
 356 static inline
 357 void loge_exception(const char *module_name)
 358 {
 359         log_exception_and_maybe_append_error(BT_LOG_ERROR, true, NULL, NULL,
 360                 NULL, module_name);
 361 }
 362
 363 static
 364 void loge_exception_message_iterator(
 365                 bt_self_message_iterator *self_message_iterator)
 366 {
 367         log_exception_and_maybe_append_error(BT_LOG_ERROR, true, NULL, NULL,
 368                 self_message_iterator, NULL);
 369 }
 370
 371 static inline
 372 void logw_exception(void)
 373 {
 374         log_exception_and_maybe_append_error(BT_LOG_WARNING, false, NULL, NULL,
 375                 NULL, NULL);
 376 }
 377
 378 static inline
 379 int py_exc_to_status(bt_self_component_class *self_component_class,
 380                 bt_self_component *self_component,
 381                 bt_self_message_iterator *self_message_iterator,
 382                 const char *module_name)
 383 {
 384         int status = __BT_FUNC_STATUS_OK;
 385         PyObject *exc = PyErr_Occurred();
 386
 387         if (!exc) {
 388                 goto end;
 389         }
 390
 391         if (PyErr_GivenExceptionMatches(exc,
 392                         py_mod_bt2_exc_try_again_type)) {
 393                 status = __BT_FUNC_STATUS_AGAIN;
 394         } else if (PyErr_GivenExceptionMatches(exc,
 395                         py_mod_bt2_exc_stop_type)) {
 396                 status = __BT_FUNC_STATUS_END;
 397         } else if (PyErr_GivenExceptionMatches(exc,
 398                         py_mod_bt2_exc_invalid_object_type)) {
 399                 status = __BT_FUNC_STATUS_INVALID_OBJECT;
 400         } else if (PyErr_GivenExceptionMatches(exc,
 401                         py_mod_bt2_exc_invalid_params_type)) {
 402                 status = __BT_FUNC_STATUS_INVALID_PARAMS;
 403         } else {
 404                 /* Unknown exception: convert to general error */
 405                 log_exception_and_maybe_append_error(BT_LOG_WARNING, true,
 406                         self_component_class, self_component,
 407                         self_message_iterator, module_name);
 408
 409                 if (PyErr_GivenExceptionMatches(exc,
 410                                 py_mod_bt2_exc_memory_error)) {
 411                         status = __BT_FUNC_STATUS_MEMORY_ERROR;
 412                 } else {
 413                         status = __BT_FUNC_STATUS_ERROR;
 414                 }
 415         }
 416
 417 end:
 418         PyErr_Clear();
 419         return status;
 420 }
 421
 422 static
 423 int py_exc_to_status_component_class(bt_self_component_class *self_component_class)
 424 {
 425         return py_exc_to_status(self_component_class, NULL, NULL, NULL);
 426 }
 427
 428 static
 429 int py_exc_to_status_component(bt_self_component *self_component)
 430 {
 431         return py_exc_to_status(NULL, self_component, NULL, NULL);
 432 }
 433
 434 static
 435 int py_exc_to_status_message_iterator(
 436                 bt_self_message_iterator *self_message_iterator)
 437 {
 438         return py_exc_to_status(NULL, NULL, self_message_iterator, NULL);
 439 }
 440
 441 /* Component class proxy methods (delegate to the attached Python object) */
 442
 443 static
 444 bt_component_class_init_method_status component_class_init(
 445                 bt_self_component *self_component,
 446                 void *self_component_v,
 447                 swig_type_info *self_comp_cls_type_swig_type,
 448                 const bt_value *params,
 449                 void *init_method_data)
 450 {
 451         const bt_component *component = bt_self_component_as_component(self_component);
 452         const bt_component_class *component_class = bt_component_borrow_class_const(component);
 453         bt_component_class_init_method_status status = __BT_FUNC_STATUS_OK;
 454         PyObject *py_cls = NULL;
 455         PyObject *py_comp = NULL;
 456         PyObject *py_params_ptr = NULL;
 457         PyObject *py_comp_ptr = NULL;
 458
 459         (void) init_method_data;
 460
 461         BT_ASSERT(self_component);
 462         BT_ASSERT(self_component_v);
 463         BT_ASSERT(self_comp_cls_type_swig_type);
 464
 465         /*
 466          * Get the user-defined Python class which created this
 467          * component's class in the first place (borrowed
 468          * reference).
 469          */
 470         py_cls = lookup_cc_ptr_to_py_cls(component_class);
 471         if (!py_cls) {
 472                 BT_LOGE("Cannot find Python class associated to native component class: "
 473                         "comp-cls-addr=%p", component_class);
 474                 goto error;
 475         }
 476
 477         /* Parameters pointer -> SWIG pointer Python object */
 478         py_params_ptr = SWIG_NewPointerObj(SWIG_as_voidptr(params),
 479                 SWIGTYPE_p_bt_value, 0);
 480         if (!py_params_ptr) {
 481                 BT_LOGE_STR("Failed to create a SWIG pointer object.");
 482                 goto error;
 483         }
 484
 485         py_comp_ptr = SWIG_NewPointerObj(SWIG_as_voidptr(self_component_v),
 486                 self_comp_cls_type_swig_type, 0);
 487         if (!py_comp_ptr) {
 488                 BT_LOGE_STR("Failed to create a SWIG pointer object.");
 489                 goto error;
 490         }
 491
 492         /*
 493          * Do the equivalent of this:
 494          *
 495          *     py_comp = py_cls._bt_init_from_native(py_comp_ptr, py_params_ptr)
 496          *
 497          * _UserComponentType._bt_init_from_native() calls the Python
 498          * component object's __init__() function.
 499          */
 500         py_comp = PyObject_CallMethod(py_cls,
 501                 "_bt_init_from_native", "(OO)", py_comp_ptr, py_params_ptr);
 502         if (!py_comp) {
 503                 BT_LOGW("Failed to call Python class's _bt_init_from_native() method: "
 504                         "py-cls-addr=%p", py_cls);
 505                 status = py_exc_to_status_component(self_component);
 506                 goto end;
 507         }
 508
 509         /*
 510          * Our user Python component object is now fully created and
 511          * initialized by the user. Since we just created it, this
 512          * native component is its only (persistent) owner.
 513          */
 514         bt_self_component_set_data(self_component, py_comp);
 515         py_comp = NULL;
 516         goto end;
 517
 518 error:
 519         status = __BT_FUNC_STATUS_ERROR;
 520
 521         /*
 522          * Clear any exception: we're returning a bad status anyway. If
 523          * this call originated from Python (creation from a plugin's
 524          * component class, for example), then the user gets an
 525          * appropriate creation error.
 526          */
 527         PyErr_Clear();
 528
 529 end:
 530         Py_XDECREF(py_comp);
 531         Py_XDECREF(py_params_ptr);
 532         Py_XDECREF(py_comp_ptr);
 533         return status;
 534 }
 535
 536 /*
 537  * Method of bt_component_class_source to initialize a bt_self_component_source
 538  * of that class.
 539  */
 540
 541 static
 542 bt_component_class_init_method_status component_class_source_init(
 543                 bt_self_component_source *self_component_source,
 544                 const bt_value *params, void *init_method_data)
 545 {
 546         bt_self_component *self_component = bt_self_component_source_as_self_component(self_component_source);
 547         return component_class_init(
 548                 self_component,
 549                 self_component_source,
 550                 SWIGTYPE_p_bt_self_component_source,
 551                 params, init_method_data);
 552 }
 553
 554 static
 555 bt_component_class_init_method_status component_class_filter_init(
 556                 bt_self_component_filter *self_component_filter,
 557                 const bt_value *params, void *init_method_data)
 558 {
 559         bt_self_component *self_component = bt_self_component_filter_as_self_component(self_component_filter);
 560         return component_class_init(
 561                 self_component,
 562                 self_component_filter,
 563                 SWIGTYPE_p_bt_self_component_filter,
 564                 params, init_method_data);
 565 }
 566
 567 static
 568 bt_component_class_init_method_status component_class_sink_init(
 569                 bt_self_component_sink *self_component_sink,
 570                 const bt_value *params, void *init_method_data)
 571 {
 572         bt_self_component *self_component = bt_self_component_sink_as_self_component(self_component_sink);
 573         return component_class_init(
 574                 self_component,
 575                 self_component_sink,
 576                 SWIGTYPE_p_bt_self_component_sink,
 577                 params, init_method_data);
 578 }
 579
 580 static
 581 void component_class_finalize(bt_self_component *self_component)
 582 {
 583         PyObject *py_comp = bt_self_component_get_data(self_component);
 584         BT_ASSERT(py_comp);
 585
 586         /* Call user's _finalize() method */
 587         PyObject *py_method_result = PyObject_CallMethod(py_comp,
 588                 "_finalize", NULL);
 589
 590         if (PyErr_Occurred()) {
 591                 BT_LOGW("User component's _finalize() method raised an exception: ignoring:");
 592                 logw_exception();
 593         }
 594
 595         /*
 596          * Ignore any exception raised by the _finalize() method because
 597          * it won't change anything at this point: the component is
 598          * being destroyed anyway.
 599          */
 600         PyErr_Clear();
 601         Py_XDECREF(py_method_result);
 602         Py_DECREF(py_comp);
 603 }
 604
 605 static
 606 void component_class_source_finalize(bt_self_component_source *self_component_source)
 607 {
 608         bt_self_component *self_component = bt_self_component_source_as_self_component(self_component_source);
 609         component_class_finalize(self_component);
 610 }
 611
 612 static
 613 void component_class_filter_finalize(bt_self_component_filter *self_component_filter)
 614 {
 615         bt_self_component *self_component = bt_self_component_filter_as_self_component(self_component_filter);
 616         component_class_finalize(self_component);
 617 }
 618
 619 static
 620 void component_class_sink_finalize(bt_self_component_sink *self_component_sink)
 621 {
 622         bt_self_component *self_component = bt_self_component_sink_as_self_component(self_component_sink);
 623         component_class_finalize(self_component);
 624 }
 625
 626 static
 627 bt_bool component_class_can_seek_beginning(
 628                 bt_self_message_iterator *self_message_iterator)
 629 {
 630         PyObject *py_iter;
 631         PyObject *py_result = NULL;
 632         bt_bool can_seek_beginning = false;
 633
 634         py_iter = bt_self_message_iterator_get_data(self_message_iterator);
 635         BT_ASSERT(py_iter);
 636
 637         py_result = PyObject_GetAttrString(py_iter, "_bt_can_seek_beginning_from_native");
 638
 639         BT_ASSERT(!py_result || PyBool_Check(py_result));
 640
 641         if (py_result) {
 642                 can_seek_beginning = PyObject_IsTrue(py_result);
 643         } else {
 644                 /*
 645                  * Once can_seek_beginning can report errors, convert the
 646                  * exception to a status.  For now, log and return false;
 647                  */
 648                 loge_exception_message_iterator(self_message_iterator);
 649                 PyErr_Clear();
 650         }
 651
 652         Py_XDECREF(py_result);
 653
 654         return can_seek_beginning;
 655 }
 656
 657 static
 658 bt_component_class_message_iterator_seek_beginning_method_status
 659 component_class_seek_beginning(bt_self_message_iterator *self_message_iterator)
 660 {
 661         PyObject *py_iter;
 662         PyObject *py_result;
 663         bt_component_class_message_iterator_seek_beginning_method_status status;
 664
 665         py_iter = bt_self_message_iterator_get_data(self_message_iterator);
 666         BT_ASSERT(py_iter);
 667         py_result = PyObject_CallMethod(py_iter, "_bt_seek_beginning_from_native",
 668                 NULL);
 669         BT_ASSERT(!py_result || py_result == Py_None);
 670         status = py_exc_to_status_message_iterator(self_message_iterator);
 671         Py_XDECREF(py_result);
 672         return status;
 673 }
 674
 675 static
 676 bt_component_class_port_connected_method_status component_class_port_connected(
 677                 bt_self_component *self_component,
 678                 void *self_component_port,
 679                 swig_type_info *self_component_port_swig_type,
 680                 bt_port_type self_component_port_type,
 681                 const void *other_port,
 682                 swig_type_info *other_port_swig_type)
 683 {
 684         bt_component_class_port_connected_method_status status;
 685         PyObject *py_comp = NULL;
 686         PyObject *py_self_port_ptr = NULL;
 687         PyObject *py_other_port_ptr = NULL;
 688         PyObject *py_method_result = NULL;
 689
 690         py_comp = bt_self_component_get_data(self_component);
 691         BT_ASSERT(py_comp);
 692         py_self_port_ptr = SWIG_NewPointerObj(SWIG_as_voidptr(self_component_port),
 693                 self_component_port_swig_type, 0);
 694         if (!py_self_port_ptr) {
 695                 BT_LOGF_STR("Failed to create a SWIG pointer object.");
 696                 status = __BT_FUNC_STATUS_MEMORY_ERROR;
 697                 goto end;
 698         }
 699
 700         py_other_port_ptr = SWIG_NewPointerObj(SWIG_as_voidptr(other_port),
 701                 other_port_swig_type, 0);
 702         if (!py_other_port_ptr) {
 703                 BT_LOGF_STR("Failed to create a SWIG pointer object.");
 704                 status = __BT_FUNC_STATUS_MEMORY_ERROR;
 705                 goto end;       }
 706
 707         py_method_result = PyObject_CallMethod(py_comp,
 708                 "_bt_port_connected_from_native", "(OiO)", py_self_port_ptr,
 709                 self_component_port_type, py_other_port_ptr);
 710         BT_ASSERT(!py_method_result || py_method_result == Py_None);
 711         status = py_exc_to_status_component(self_component);
 712
 713 end:
 714         Py_XDECREF(py_self_port_ptr);
 715         Py_XDECREF(py_other_port_ptr);
 716         Py_XDECREF(py_method_result);
 717         return status;
 718 }
 719
 720 static
 721 bt_component_class_port_connected_method_status
 722 component_class_source_output_port_connected(
 723                 bt_self_component_source *self_component_source,
 724                 bt_self_component_port_output *self_component_port_output,
 725                 const bt_port_input *other_port_input)
 726 {
 727         bt_self_component *self_component = bt_self_component_source_as_self_component(self_component_source);
 728
 729         return component_class_port_connected(
 730                 self_component,
 731                 self_component_port_output,
 732                 SWIGTYPE_p_bt_self_component_port_output,
 733                 BT_PORT_TYPE_OUTPUT,
 734                 other_port_input,
 735                 SWIGTYPE_p_bt_port_input);
 736 }
 737
 738 static
 739 bt_component_class_port_connected_method_status
 740 component_class_filter_input_port_connected(
 741                 bt_self_component_filter *self_component_filter,
 742                 bt_self_component_port_input *self_component_port_input,
 743                 const bt_port_output *other_port_output)
 744 {
 745         bt_self_component *self_component = bt_self_component_filter_as_self_component(self_component_filter);
 746
 747         return component_class_port_connected(
 748                 self_component,
 749                 self_component_port_input,
 750                 SWIGTYPE_p_bt_self_component_port_input,
 751                 BT_PORT_TYPE_INPUT,
 752                 other_port_output,
 753                 SWIGTYPE_p_bt_port_output);
 754 }
 755
 756 static
 757 bt_component_class_port_connected_method_status
 758 component_class_filter_output_port_connected(
 759                 bt_self_component_filter *self_component_filter,
 760                 bt_self_component_port_output *self_component_port_output,
 761                 const bt_port_input *other_port_input)
 762 {
 763         bt_self_component *self_component = bt_self_component_filter_as_self_component(self_component_filter);
 764
 765         return component_class_port_connected(
 766                 self_component,
 767                 self_component_port_output,
 768                 SWIGTYPE_p_bt_self_component_port_output,
 769                 BT_PORT_TYPE_OUTPUT,
 770                 other_port_input,
 771                 SWIGTYPE_p_bt_port_input);
 772 }
 773
 774 static
 775 bt_component_class_port_connected_method_status
 776 component_class_sink_input_port_connected(
 777                 bt_self_component_sink *self_component_sink,
 778                 bt_self_component_port_input *self_component_port_input,
 779                 const bt_port_output *other_port_output)
 780 {
 781         bt_self_component *self_component = bt_self_component_sink_as_self_component(self_component_sink);
 782
 783         return component_class_port_connected(
 784                 self_component,
 785                 self_component_port_input,
 786                 SWIGTYPE_p_bt_self_component_port_input,
 787                 BT_PORT_TYPE_INPUT,
 788                 other_port_output,
 789                 SWIGTYPE_p_bt_port_output);
 790 }
 791
 792 static
 793 bt_component_class_sink_graph_is_configured_method_status
 794 component_class_sink_graph_is_configured(
 795                 bt_self_component_sink *self_component_sink)
 796 {
 797         PyObject *py_comp = NULL;
 798         PyObject *py_method_result = NULL;
 799         bt_component_class_sink_graph_is_configured_method_status status = __BT_FUNC_STATUS_OK;
 800         bt_self_component *self_component = bt_self_component_sink_as_self_component(self_component_sink);
 801
 802         py_comp = bt_self_component_get_data(self_component);
 803         py_method_result = PyObject_CallMethod(py_comp,
 804                 "_bt_graph_is_configured_from_native", NULL);
 805         BT_ASSERT(!py_method_result || py_method_result == Py_None);
 806         status = py_exc_to_status_component(self_component);
 807         Py_XDECREF(py_method_result);
 808         return status;
 809 }
 810
 811 static
 812 bt_component_class_query_method_status component_class_query(
 813                 const bt_component_class *component_class,
 814                 bt_self_component_class *self_component_class,
 815                 const bt_query_executor *query_executor,
 816                 const char *object, const bt_value *params,
 817                 bt_logging_level log_level,
 818                 const bt_value **result)
 819 {
 820         PyObject *py_cls = NULL;
 821         PyObject *py_params_ptr = NULL;
 822         PyObject *py_query_exec_ptr = NULL;
 823         PyObject *py_query_func = NULL;
 824         PyObject *py_object = NULL;
 825         PyObject *py_results_addr = NULL;
 826         bt_component_class_query_method_status status = __BT_FUNC_STATUS_OK;
 827
 828         py_cls = lookup_cc_ptr_to_py_cls(component_class);
 829         if (!py_cls) {
 830                 BT_LOGE("Cannot find Python class associated to native component class: "
 831                         "comp-cls-addr=%p", component_class);
 832                 goto error;
 833         }
 834
 835         py_params_ptr = SWIG_NewPointerObj(SWIG_as_voidptr(params),
 836                 SWIGTYPE_p_bt_value, 0);
 837         if (!py_params_ptr) {
 838                 BT_LOGE_STR("Failed to create a SWIG pointer object.");
 839                 goto error;
 840         }
 841
 842         py_query_exec_ptr = SWIG_NewPointerObj(SWIG_as_voidptr(query_executor),
 843                 SWIGTYPE_p_bt_query_executor, 0);
 844         if (!py_query_exec_ptr) {
 845                 BT_LOGE_STR("Failed to create a SWIG pointer object.");
 846                 goto error;
 847         }
 848
 849         py_object = SWIG_FromCharPtr(object);
 850         if (!py_object) {
 851                 BT_LOGE_STR("Failed to create a Python string.");
 852                 goto error;
 853         }
 854
 855         py_results_addr = PyObject_CallMethod(py_cls,
 856                 "_bt_query_from_native", "(OOOi)", py_query_exec_ptr,
 857                 py_object, py_params_ptr, (int) log_level);
 858         if (!py_results_addr) {
 859                 BT_LOGW("Failed to call Python class's _bt_query_from_native() method: "
 860                         "py-cls-addr=%p", py_cls);
 861                 status = py_exc_to_status_component_class(self_component_class);
 862                 goto end;
 863         }
 864
 865         /*
 866          * The returned object, on success, is an integer object
 867          * (PyLong) containing the address of a BT value object (new
 868          * reference).
 869          */
 870         *result = PyLong_AsVoidPtr(py_results_addr);
 871         BT_ASSERT(!PyErr_Occurred());
 872         BT_ASSERT(*result);
 873         goto end;
 874
 875 error:
 876         PyErr_Clear();
 877         status = __BT_FUNC_STATUS_ERROR;
 878
 879 end:
 880         Py_XDECREF(py_params_ptr);
 881         Py_XDECREF(py_query_exec_ptr);
 882         Py_XDECREF(py_query_func);
 883         Py_XDECREF(py_object);
 884         Py_XDECREF(py_results_addr);
 885         return status;
 886 }
 887
 888 static
 889 bt_component_class_query_method_status component_class_source_query(
 890                 bt_self_component_class_source *self_component_class_source,
 891                 const bt_query_executor *query_executor,
 892                 const char *object, const bt_value *params,
 893                 bt_logging_level log_level,
 894                 const bt_value **result)
 895 {
 896         const bt_component_class_source *component_class_source = bt_self_component_class_source_as_component_class_source(self_component_class_source);
 897         const bt_component_class *component_class = bt_component_class_source_as_component_class_const(component_class_source);
 898         bt_self_component_class *self_component_class = bt_self_component_class_source_as_self_component_class(self_component_class_source);
 899
 900         return component_class_query(component_class, self_component_class, query_executor, object, params, log_level, result);
 901 }
 902
 903 static
 904 bt_component_class_query_method_status component_class_filter_query(
 905                 bt_self_component_class_filter *self_component_class_filter,
 906                 const bt_query_executor *query_executor,
 907                 const char *object, const bt_value *params,
 908                 bt_logging_level log_level,
 909                 const bt_value **result)
 910 {
 911         const bt_component_class_filter *component_class_filter = bt_self_component_class_filter_as_component_class_filter(self_component_class_filter);
 912         const bt_component_class *component_class = bt_component_class_filter_as_component_class_const(component_class_filter);
 913         bt_self_component_class *self_component_class = bt_self_component_class_filter_as_self_component_class(self_component_class_filter);
 914
 915         return component_class_query(component_class, self_component_class, query_executor, object, params, log_level, result);
 916 }
 917
 918 static
 919 bt_component_class_query_method_status component_class_sink_query(
 920                 bt_self_component_class_sink *self_component_class_sink,
 921                 const bt_query_executor *query_executor,
 922                 const char *object, const bt_value *params,
 923                 bt_logging_level log_level,
 924                 const bt_value **result)
 925 {
 926         const bt_component_class_sink *component_class_sink = bt_self_component_class_sink_as_component_class_sink(self_component_class_sink);
 927         const bt_component_class *component_class = bt_component_class_sink_as_component_class_const(component_class_sink);
 928         bt_self_component_class *self_component_class = bt_self_component_class_sink_as_self_component_class(self_component_class_sink);
 929
 930         return component_class_query(component_class, self_component_class, query_executor, object, params, log_level, result);
 931 }
 932
 933 static
 934 bt_component_class_message_iterator_init_method_status
 935 component_class_message_iterator_init(
 936                 bt_self_message_iterator *self_message_iterator,
 937                 bt_self_component *self_component,
 938                 bt_self_component_port_output *self_component_port_output)
 939 {
 940         bt_component_class_message_iterator_init_method_status status = __BT_FUNC_STATUS_OK;
 941         PyObject *py_comp_cls = NULL;
 942         PyObject *py_iter_cls = NULL;
 943         PyObject *py_iter_ptr = NULL;
 944         PyObject *py_component_port_output_ptr = NULL;
 945         PyObject *py_init_method_result = NULL;
 946         PyObject *py_iter = NULL;
 947         PyObject *py_comp;
 948
 949         py_comp = bt_self_component_get_data(self_component);
 950
 951         /* Find user's Python message iterator class */
 952         py_comp_cls = PyObject_GetAttrString(py_comp, "__class__");
 953         if (!py_comp_cls) {
 954                 BT_LOGE_STR("Cannot get Python object's `__class__` attribute.");
 955                 goto python_error;
 956         }
 957
 958         py_iter_cls = PyObject_GetAttrString(py_comp_cls, "_iter_cls");
 959         if (!py_iter_cls) {
 960                 BT_LOGE_STR("Cannot get Python class's `_iter_cls` attribute.");
 961                 goto python_error;
 962         }
 963
 964         py_iter_ptr = SWIG_NewPointerObj(SWIG_as_voidptr(self_message_iterator),
 965                 SWIGTYPE_p_bt_self_message_iterator, 0);
 966         if (!py_iter_ptr) {
 967                 const char *err = "Failed to create a SWIG pointer object.";
 968
 969                 BT_LOGE_STR(err);
 970                 BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_MESSAGE_ITERATOR(
 971                         self_message_iterator, err);
 972                 goto error;
 973         }
 974
 975         /*
 976          * Create object with borrowed native message iterator
 977          * reference:
 978          *
 979          *     py_iter = py_iter_cls.__new__(py_iter_cls, py_iter_ptr)
 980          */
 981         py_iter = PyObject_CallMethod(py_iter_cls, "__new__",
 982                 "(OO)", py_iter_cls, py_iter_ptr);
 983         if (!py_iter) {
 984                 BT_LOGE("Failed to call Python class's __new__() method: "
 985                         "py-cls-addr=%p", py_iter_cls);
 986                 goto python_error;
 987         }
 988
 989         /*
 990          * Initialize object:
 991          *
 992          *     py_iter.__init__(self_output_port)
 993          *
 994          * through the _init_for_native helper static method.
 995          *
 996          * At this point, py_iter._ptr is set, so this initialization
 997          * function has access to self._component (which gives it the
 998          * user Python component object from which the iterator was
 999          * created).
1000          */
1001         py_component_port_output_ptr = SWIG_NewPointerObj(
1002                 SWIG_as_voidptr(self_component_port_output),
1003                 SWIGTYPE_p_bt_self_component_port_output, 0);
1004         if (!py_component_port_output_ptr) {
1005                 const char *err = "Failed to create a SWIG pointer object.";
1006
1007                 BT_LOGE_STR(err);
1008                 BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_MESSAGE_ITERATOR(
1009                         self_message_iterator, err);
1010                 goto error;
1011         }
1012
1013         py_init_method_result = PyObject_CallMethod(py_iter,
1014                 "_bt_init_from_native", "O", py_component_port_output_ptr);
1015         if (!py_init_method_result) {
1016                 BT_LOGE_STR("User's __init__() method failed:");
1017                 goto python_error;
1018         }
1019
1020         /*
1021          * Since the Python code can never instantiate a user-defined
1022          * message iterator class, the native message iterator
1023          * object does NOT belong to a user Python message iterator
1024          * object (borrowed reference). However this Python object is
1025          * owned by this native message iterator object.
1026          *
1027          * In the Python world, the lifetime of the native message
1028          * iterator is managed by a _GenericMessageIterator
1029          * instance:
1030          *
1031          *     _GenericMessageIterator instance:
1032          *         owns a native bt_message_iterator object (iter)
1033          *             owns a _UserMessageIterator instance (py_iter)
1034          *                 self._ptr is a borrowed reference to the
1035          *                 native bt_private_connection_private_message_iterator
1036          *                 object (iter)
1037          */
1038         bt_self_message_iterator_set_data(self_message_iterator, py_iter);
1039         py_iter = NULL;
1040         goto end;
1041
1042 python_error:
1043         /* Handling of errors that cause a Python exception to be set. */
1044         status = py_exc_to_status_message_iterator(self_message_iterator);
1045         BT_ASSERT(status != __BT_FUNC_STATUS_OK);
1046         goto end;
1047
1048 error:
1049         /* Handling of errors that don't cause a Python exception to be set. */
1050         status = __BT_FUNC_STATUS_ERROR;
1051
1052 end:
1053         BT_ASSERT(!PyErr_Occurred());
1054
1055         Py_XDECREF(py_comp_cls);
1056         Py_XDECREF(py_iter_cls);
1057         Py_XDECREF(py_iter_ptr);
1058         Py_XDECREF(py_component_port_output_ptr);
1059         Py_XDECREF(py_init_method_result);
1060         Py_XDECREF(py_iter);
1061         return status;
1062 }
1063
1064 static
1065 bt_component_class_message_iterator_init_method_status
1066 component_class_source_message_iterator_init(
1067                 bt_self_message_iterator *self_message_iterator,
1068                 bt_self_component_source *self_component_source,
1069                 bt_self_component_port_output *self_component_port_output)
1070 {
1071         bt_self_component *self_component = bt_self_component_source_as_self_component(self_component_source);
1072
1073         return component_class_message_iterator_init(self_message_iterator, self_component, self_component_port_output);
1074 }
1075
1076 static
1077 bt_component_class_message_iterator_init_method_status
1078 component_class_filter_message_iterator_init(
1079                 bt_self_message_iterator *self_message_iterator,
1080                 bt_self_component_filter *self_component_filter,
1081                 bt_self_component_port_output *self_component_port_output)
1082 {
1083         bt_self_component *self_component = bt_self_component_filter_as_self_component(self_component_filter);
1084
1085         return component_class_message_iterator_init(self_message_iterator, self_component, self_component_port_output);
1086 }
1087
1088 static
1089 void component_class_message_iterator_finalize(
1090                 bt_self_message_iterator *message_iterator)
1091 {
1092         PyObject *py_message_iter = bt_self_message_iterator_get_data(message_iterator);
1093         PyObject *py_method_result = NULL;
1094
1095         BT_ASSERT(py_message_iter);
1096
1097         /* Call user's _finalize() method */
1098         py_method_result = PyObject_CallMethod(py_message_iter,
1099                 "_finalize", NULL);
1100
1101         if (PyErr_Occurred()) {
1102                 BT_LOGW("User's _finalize() method raised an exception: ignoring:");
1103                 logw_exception();
1104         }
1105
1106         /*
1107          * Ignore any exception raised by the _finalize() method because
1108          * it won't change anything at this point: the component is
1109          * being destroyed anyway.
1110          */
1111         PyErr_Clear();
1112         Py_XDECREF(py_method_result);
1113         Py_DECREF(py_message_iter);
1114 }
1115
1116 /* Valid for both sources and filters. */
1117
1118 static
1119 bt_component_class_message_iterator_next_method_status
1120 component_class_message_iterator_next(
1121                 bt_self_message_iterator *message_iterator,
1122                 bt_message_array_const msgs, uint64_t capacity,
1123                 uint64_t *count)
1124 {
1125         bt_component_class_message_iterator_next_method_status status = __BT_FUNC_STATUS_OK;
1126         PyObject *py_message_iter = bt_self_message_iterator_get_data(message_iterator);
1127         PyObject *py_method_result = NULL;
1128
1129         BT_ASSERT(py_message_iter);
1130         py_method_result = PyObject_CallMethod(py_message_iter,
1131                 "_bt_next_from_native", NULL);
1132         if (!py_method_result) {
1133                 status = py_exc_to_status_message_iterator(message_iterator);
1134                 BT_ASSERT(status != __BT_FUNC_STATUS_OK);
1135                 goto end;
1136         }
1137
1138         /*
1139          * The returned object, on success, is an integer object
1140          * (PyLong) containing the address of a native message
1141          * object (which is now ours).
1142          */
1143         msgs[0] = PyLong_AsVoidPtr(py_method_result);
1144         *count = 1;
1145
1146         /* Clear potential overflow error; should never happen */
1147         BT_ASSERT(!PyErr_Occurred());
1148         goto end;
1149
1150 end:
1151         Py_XDECREF(py_method_result);
1152         return status;
1153 }
1154
1155 static
1156 bt_component_class_sink_consume_method_status
1157 component_class_sink_consume(bt_self_component_sink *self_component_sink)
1158 {
1159         bt_self_component *self_component = bt_self_component_sink_as_self_component(self_component_sink);
1160         PyObject *py_comp = bt_self_component_get_data(self_component);
1161         PyObject *py_method_result = NULL;
1162         bt_component_class_sink_consume_method_status status;
1163
1164         BT_ASSERT(py_comp);
1165         py_method_result = PyObject_CallMethod(py_comp,
1166                 "_consume", NULL);
1167         status = py_exc_to_status_component(self_component);
1168         if (!py_method_result && status == __BT_FUNC_STATUS_OK) {
1169                 /* Pretty sure this should never happen, but just in case */
1170                 BT_LOGE("User's _consume() method failed without raising an exception: "
1171                         "status=%d", status);
1172                 status = __BT_FUNC_STATUS_ERROR;
1173         }
1174
1175         Py_XDECREF(py_method_result);
1176         return status;
1177 }
1178
1179 static
1180 int component_class_set_help_and_desc(
1181                 bt_component_class *component_class,
1182                 const char *description, const char *help)
1183 {
1184         int ret;
1185
1186         if (description) {
1187                 ret = bt_component_class_set_description(component_class, description);
1188                 if (ret) {
1189                         BT_LOGE("Cannot set component class's description: "
1190                                 "comp-cls-addr=%p", component_class);
1191                         goto end;
1192                 }
1193         }
1194
1195         if (help) {
1196                 ret = bt_component_class_set_help(component_class, help);
1197                 if (ret) {
1198                         BT_LOGE("Cannot set component class's help text: "
1199                                 "comp-cls-addr=%p", component_class);
1200                         goto end;
1201                 }
1202         }
1203
1204         ret = 0;
1205
1206 end:
1207         return ret;
1208 }
1209
1210 static
1211 bt_component_class_source *bt_bt2_component_class_source_create(
1212                 PyObject *py_cls, const char *name, const char *description,
1213                 const char *help)
1214 {
1215         bt_component_class_source *component_class_source;
1216         bt_component_class *component_class;
1217         int ret;
1218
1219         BT_ASSERT(py_cls);
1220         component_class_source = bt_component_class_source_create(name,
1221                 component_class_message_iterator_next);
1222         if (!component_class_source) {
1223                 BT_LOGE_STR("Cannot create source component class.");
1224                 goto end;
1225         }
1226
1227         component_class = bt_component_class_source_as_component_class(component_class_source);
1228
1229         if (component_class_set_help_and_desc(component_class, description, help)) {
1230                 goto end;
1231         }
1232
1233         ret = bt_component_class_source_set_init_method(component_class_source, component_class_source_init);
1234         BT_ASSERT(ret == 0);
1235         ret = bt_component_class_source_set_finalize_method(component_class_source, component_class_source_finalize);
1236         BT_ASSERT(ret == 0);
1237         ret = bt_component_class_source_set_message_iterator_can_seek_beginning_method(component_class_source,
1238                 component_class_can_seek_beginning);
1239         BT_ASSERT(ret == 0);
1240         ret = bt_component_class_source_set_message_iterator_seek_beginning_method(component_class_source,
1241                 component_class_seek_beginning);
1242         BT_ASSERT(ret == 0);
1243         ret = bt_component_class_source_set_output_port_connected_method(component_class_source,
1244                 component_class_source_output_port_connected);
1245         BT_ASSERT(ret == 0);
1246         ret = bt_component_class_source_set_query_method(component_class_source, component_class_source_query);
1247         BT_ASSERT(ret == 0);
1248         ret = bt_component_class_source_set_message_iterator_init_method(
1249                 component_class_source, component_class_source_message_iterator_init);
1250         BT_ASSERT(ret == 0);
1251         ret = bt_component_class_source_set_message_iterator_finalize_method(
1252                 component_class_source, component_class_message_iterator_finalize);
1253         BT_ASSERT(ret == 0);
1254         register_cc_ptr_to_py_cls(component_class, py_cls);
1255
1256 end:
1257         return component_class_source;
1258 }
1259
1260 static
1261 bt_component_class_filter *bt_bt2_component_class_filter_create(
1262                 PyObject *py_cls, const char *name, const char *description,
1263                 const char *help)
1264 {
1265         bt_component_class *component_class;
1266         bt_component_class_filter *component_class_filter;
1267         int ret;
1268
1269         BT_ASSERT(py_cls);
1270         component_class_filter = bt_component_class_filter_create(name,
1271                 component_class_message_iterator_next);
1272         if (!component_class_filter) {
1273                 BT_LOGE_STR("Cannot create filter component class.");
1274                 goto end;
1275         }
1276
1277         component_class = bt_component_class_filter_as_component_class(component_class_filter);
1278
1279         if (component_class_set_help_and_desc(component_class, description, help)) {
1280                 goto end;
1281         }
1282
1283         ret = bt_component_class_filter_set_init_method(component_class_filter, component_class_filter_init);
1284         BT_ASSERT(ret == 0);
1285         ret = bt_component_class_filter_set_finalize_method (component_class_filter, component_class_filter_finalize);
1286         BT_ASSERT(ret == 0);
1287         ret = bt_component_class_filter_set_message_iterator_can_seek_beginning_method(component_class_filter,
1288                 component_class_can_seek_beginning);
1289         BT_ASSERT(ret == 0);
1290         ret = bt_component_class_filter_set_message_iterator_seek_beginning_method(component_class_filter,
1291                 component_class_seek_beginning);
1292         BT_ASSERT(ret == 0);
1293         ret = bt_component_class_filter_set_input_port_connected_method(component_class_filter,
1294                 component_class_filter_input_port_connected);
1295         BT_ASSERT(ret == 0);
1296         ret = bt_component_class_filter_set_output_port_connected_method(component_class_filter,
1297                 component_class_filter_output_port_connected);
1298         BT_ASSERT(ret == 0);
1299         ret = bt_component_class_filter_set_query_method(component_class_filter, component_class_filter_query);
1300         BT_ASSERT(ret == 0);
1301         ret = bt_component_class_filter_set_message_iterator_init_method(
1302                 component_class_filter, component_class_filter_message_iterator_init);
1303         BT_ASSERT(ret == 0);
1304         ret = bt_component_class_filter_set_message_iterator_finalize_method(
1305                 component_class_filter, component_class_message_iterator_finalize);
1306         BT_ASSERT(ret == 0);
1307         register_cc_ptr_to_py_cls(component_class, py_cls);
1308
1309 end:
1310         return component_class_filter;
1311 }
1312
1313 static
1314 bt_component_class_sink *bt_bt2_component_class_sink_create(
1315                 PyObject *py_cls, const char *name, const char *description,
1316                 const char *help)
1317 {
1318         bt_component_class_sink *component_class_sink;
1319         bt_component_class *component_class;
1320         int ret;
1321
1322         BT_ASSERT(py_cls);
1323         component_class_sink = bt_component_class_sink_create(name, component_class_sink_consume);
1324
1325         if (!component_class_sink) {
1326                 BT_LOGE_STR("Cannot create sink component class.");
1327                 goto end;
1328         }
1329
1330         component_class = bt_component_class_sink_as_component_class(component_class_sink);
1331
1332         if (component_class_set_help_and_desc(component_class, description, help)) {
1333                 goto end;
1334         }
1335
1336         ret = bt_component_class_sink_set_init_method(component_class_sink, component_class_sink_init);
1337         BT_ASSERT(ret == 0);
1338         ret = bt_component_class_sink_set_finalize_method(component_class_sink, component_class_sink_finalize);
1339         BT_ASSERT(ret == 0);
1340         ret = bt_component_class_sink_set_input_port_connected_method(component_class_sink,
1341                 component_class_sink_input_port_connected);
1342         BT_ASSERT(ret == 0);
1343         ret = bt_component_class_sink_set_graph_is_configured_method(component_class_sink,
1344                 component_class_sink_graph_is_configured);
1345         BT_ASSERT(ret == 0);
1346         ret = bt_component_class_sink_set_query_method(component_class_sink, component_class_sink_query);
1347         BT_ASSERT(ret == 0);
1348         register_cc_ptr_to_py_cls(component_class, py_cls);
1349
1350 end:
1351         return component_class_sink;
1352 }
1353 %}
1354
1355 struct bt_component_class_source *bt_bt2_component_class_source_create(
1356                 PyObject *py_cls, const char *name, const char *description,
1357                 const char *help);
1358 struct bt_component_class_filter *bt_bt2_component_class_filter_create(
1359                 PyObject *py_cls, const char *name, const char *description,
1360                 const char *help);
1361 struct bt_component_class_sink *bt_bt2_component_class_sink_create(
1362                 PyObject *py_cls, const char *name, const char *description,
1363                 const char *help);
1364 void bt_bt2_cc_init_from_bt2(void);
1365 void bt_bt2_cc_exit_handler(void);