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_try_again_type = NULL;
  98 static PyObject *py_mod_bt2_exc_stop_type = NULL;
  99 static PyObject *py_mod_bt2_exc_msg_iter_canceled_type = NULL;
 100 static PyObject *py_mod_bt2_exc_invalid_object_type = NULL;
 101 static PyObject *py_mod_bt2_exc_invalid_params_type = NULL;
 102 static PyObject *py_mod_bt2_exc_unsupported_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_try_again_type =
 121                 PyObject_GetAttrString(py_mod_bt2, "TryAgain");
 122         BT_ASSERT(py_mod_bt2_exc_try_again_type);
 123         py_mod_bt2_exc_stop_type =
 124                 PyObject_GetAttrString(py_mod_bt2, "Stop");
 125         BT_ASSERT(py_mod_bt2_exc_stop_type);
 126         py_mod_bt2_exc_invalid_object_type =
 127                 PyObject_GetAttrString(py_mod_bt2, "InvalidObject");
 128         BT_ASSERT(py_mod_bt2_exc_invalid_object_type);
 129         py_mod_bt2_exc_invalid_params_type =
 130                 PyObject_GetAttrString(py_mod_bt2, "InvalidParams");
 131         BT_ASSERT(py_mod_bt2_exc_invalid_params_type);
 132         py_mod_bt2_exc_unsupported_type =
 133                 PyObject_GetAttrString(py_mod_bt2, "Unsupported");
 134         BT_ASSERT(py_mod_bt2_exc_unsupported_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 if (PyErr_GivenExceptionMatches(exc,
 404                         py_mod_bt2_exc_unsupported_type)) {
 405                 status = __BT_FUNC_STATUS_UNSUPPORTED;
 406         } else {
 407                 /* Unknown exception: convert to general error */
 408                 log_exception_and_maybe_append_error(BT_LOG_WARNING, true,
 409                         self_component_class, self_component,
 410                         self_message_iterator, module_name);
 411                 status = __BT_FUNC_STATUS_ERROR;
 412         }
 413
 414 end:
 415         PyErr_Clear();
 416         return status;
 417 }
 418
 419 static
 420 int py_exc_to_status_component_class(bt_self_component_class *self_component_class)
 421 {
 422         return py_exc_to_status(self_component_class, NULL, NULL, NULL);
 423 }
 424
 425 static
 426 int py_exc_to_status_component(bt_self_component *self_component)
 427 {
 428         return py_exc_to_status(NULL, self_component, NULL, NULL);
 429 }
 430
 431 static
 432 int py_exc_to_status_message_iterator(
 433                 bt_self_message_iterator *self_message_iterator)
 434 {
 435         return py_exc_to_status(NULL, NULL, self_message_iterator, NULL);
 436 }
 437
 438 /* Component class proxy methods (delegate to the attached Python object) */
 439
 440 static
 441 bt_component_class_init_method_status component_class_init(
 442                 bt_self_component *self_component,
 443                 void *self_component_v,
 444                 swig_type_info *self_comp_cls_type_swig_type,
 445                 const bt_value *params,
 446                 void *init_method_data)
 447 {
 448         const bt_component *component = bt_self_component_as_component(self_component);
 449         const bt_component_class *component_class = bt_component_borrow_class_const(component);
 450         bt_component_class_init_method_status status = __BT_FUNC_STATUS_OK;
 451         PyObject *py_cls = NULL;
 452         PyObject *py_comp = NULL;
 453         PyObject *py_params_ptr = NULL;
 454         PyObject *py_comp_ptr = NULL;
 455
 456         (void) init_method_data;
 457
 458         BT_ASSERT(self_component);
 459         BT_ASSERT(self_component_v);
 460         BT_ASSERT(self_comp_cls_type_swig_type);
 461
 462         /*
 463          * Get the user-defined Python class which created this
 464          * component's class in the first place (borrowed
 465          * reference).
 466          */
 467         py_cls = lookup_cc_ptr_to_py_cls(component_class);
 468         if (!py_cls) {
 469                 BT_LOGE("Cannot find Python class associated to native component class: "
 470                         "comp-cls-addr=%p", component_class);
 471                 goto error;
 472         }
 473
 474         /* Parameters pointer -> SWIG pointer Python object */
 475         py_params_ptr = SWIG_NewPointerObj(SWIG_as_voidptr(params),
 476                 SWIGTYPE_p_bt_value, 0);
 477         if (!py_params_ptr) {
 478                 BT_LOGE_STR("Failed to create a SWIG pointer object.");
 479                 goto error;
 480         }
 481
 482         py_comp_ptr = SWIG_NewPointerObj(SWIG_as_voidptr(self_component_v),
 483                 self_comp_cls_type_swig_type, 0);
 484         if (!py_comp_ptr) {
 485                 BT_LOGE_STR("Failed to create a SWIG pointer object.");
 486                 goto error;
 487         }
 488
 489         /*
 490          * Do the equivalent of this:
 491          *
 492          *     py_comp = py_cls._bt_init_from_native(py_comp_ptr, py_params_ptr)
 493          *
 494          * _UserComponentType._bt_init_from_native() calls the Python
 495          * component object's __init__() function.
 496          */
 497         py_comp = PyObject_CallMethod(py_cls,
 498                 "_bt_init_from_native", "(OO)", py_comp_ptr, py_params_ptr);
 499         if (!py_comp) {
 500                 BT_LOGW("Failed to call Python class's _bt_init_from_native() method: "
 501                         "py-cls-addr=%p", py_cls);
 502                 status = py_exc_to_status_component(self_component);
 503                 goto end;
 504         }
 505
 506         /*
 507          * Our user Python component object is now fully created and
 508          * initialized by the user. Since we just created it, this
 509          * native component is its only (persistent) owner.
 510          */
 511         bt_self_component_set_data(self_component, py_comp);
 512         py_comp = NULL;
 513         goto end;
 514
 515 error:
 516         status = __BT_FUNC_STATUS_ERROR;
 517
 518         /*
 519          * Clear any exception: we're returning a bad status anyway. If
 520          * this call originated from Python (creation from a plugin's
 521          * component class, for example), then the user gets an
 522          * appropriate creation error.
 523          */
 524         PyErr_Clear();
 525
 526 end:
 527         Py_XDECREF(py_comp);
 528         Py_XDECREF(py_params_ptr);
 529         Py_XDECREF(py_comp_ptr);
 530         return status;
 531 }
 532
 533 /*
 534  * Method of bt_component_class_source to initialize a bt_self_component_source
 535  * of that class.
 536  */
 537
 538 static
 539 bt_component_class_init_method_status component_class_source_init(
 540                 bt_self_component_source *self_component_source,
 541                 const bt_value *params, void *init_method_data)
 542 {
 543         bt_self_component *self_component = bt_self_component_source_as_self_component(self_component_source);
 544         return component_class_init(
 545                 self_component,
 546                 self_component_source,
 547                 SWIGTYPE_p_bt_self_component_source,
 548                 params, init_method_data);
 549 }
 550
 551 static
 552 bt_component_class_init_method_status component_class_filter_init(
 553                 bt_self_component_filter *self_component_filter,
 554                 const bt_value *params, void *init_method_data)
 555 {
 556         bt_self_component *self_component = bt_self_component_filter_as_self_component(self_component_filter);
 557         return component_class_init(
 558                 self_component,
 559                 self_component_filter,
 560                 SWIGTYPE_p_bt_self_component_filter,
 561                 params, init_method_data);
 562 }
 563
 564 static
 565 bt_component_class_init_method_status component_class_sink_init(
 566                 bt_self_component_sink *self_component_sink,
 567                 const bt_value *params, void *init_method_data)
 568 {
 569         bt_self_component *self_component = bt_self_component_sink_as_self_component(self_component_sink);
 570         return component_class_init(
 571                 self_component,
 572                 self_component_sink,
 573                 SWIGTYPE_p_bt_self_component_sink,
 574                 params, init_method_data);
 575 }
 576
 577 static
 578 void component_class_finalize(bt_self_component *self_component)
 579 {
 580         PyObject *py_comp = bt_self_component_get_data(self_component);
 581         BT_ASSERT(py_comp);
 582
 583         /* Call user's _finalize() method */
 584         PyObject *py_method_result = PyObject_CallMethod(py_comp,
 585                 "_finalize", NULL);
 586
 587         if (PyErr_Occurred()) {
 588                 BT_LOGW("User component's _finalize() method raised an exception: ignoring:");
 589                 logw_exception();
 590         }
 591
 592         /*
 593          * Ignore any exception raised by the _finalize() method because
 594          * it won't change anything at this point: the component is
 595          * being destroyed anyway.
 596          */
 597         PyErr_Clear();
 598         Py_XDECREF(py_method_result);
 599         Py_DECREF(py_comp);
 600 }
 601
 602 static
 603 void component_class_source_finalize(bt_self_component_source *self_component_source)
 604 {
 605         bt_self_component *self_component = bt_self_component_source_as_self_component(self_component_source);
 606         component_class_finalize(self_component);
 607 }
 608
 609 static
 610 void component_class_filter_finalize(bt_self_component_filter *self_component_filter)
 611 {
 612         bt_self_component *self_component = bt_self_component_filter_as_self_component(self_component_filter);
 613         component_class_finalize(self_component);
 614 }
 615
 616 static
 617 void component_class_sink_finalize(bt_self_component_sink *self_component_sink)
 618 {
 619         bt_self_component *self_component = bt_self_component_sink_as_self_component(self_component_sink);
 620         component_class_finalize(self_component);
 621 }
 622
 623 static
 624 bt_bool component_class_can_seek_beginning(
 625                 bt_self_message_iterator *self_message_iterator)
 626 {
 627         PyObject *py_iter;
 628         PyObject *py_result = NULL;
 629         bt_bool can_seek_beginning = false;
 630
 631         py_iter = bt_self_message_iterator_get_data(self_message_iterator);
 632         BT_ASSERT(py_iter);
 633
 634         py_result = PyObject_GetAttrString(py_iter, "_bt_can_seek_beginning_from_native");
 635
 636         BT_ASSERT(!py_result || PyBool_Check(py_result));
 637
 638         if (py_result) {
 639                 can_seek_beginning = PyObject_IsTrue(py_result);
 640         } else {
 641                 /*
 642                  * Once can_seek_beginning can report errors, convert the
 643                  * exception to a status.  For now, log and return false;
 644                  */
 645                 loge_exception_message_iterator(self_message_iterator);
 646                 PyErr_Clear();
 647         }
 648
 649         Py_XDECREF(py_result);
 650
 651         return can_seek_beginning;
 652 }
 653
 654 static
 655 bt_component_class_message_iterator_seek_beginning_method_status
 656 component_class_seek_beginning(bt_self_message_iterator *self_message_iterator)
 657 {
 658         PyObject *py_iter;
 659         PyObject *py_result;
 660         bt_component_class_message_iterator_seek_beginning_method_status status;
 661
 662         py_iter = bt_self_message_iterator_get_data(self_message_iterator);
 663         BT_ASSERT(py_iter);
 664         py_result = PyObject_CallMethod(py_iter, "_bt_seek_beginning_from_native",
 665                 NULL);
 666         BT_ASSERT(!py_result || py_result == Py_None);
 667         status = py_exc_to_status_message_iterator(self_message_iterator);
 668         Py_XDECREF(py_result);
 669         return status;
 670 }
 671
 672 static
 673 bt_component_class_port_connected_method_status component_class_port_connected(
 674                 bt_self_component *self_component,
 675                 void *self_component_port,
 676                 swig_type_info *self_component_port_swig_type,
 677                 bt_port_type self_component_port_type,
 678                 const void *other_port,
 679                 swig_type_info *other_port_swig_type)
 680 {
 681         bt_component_class_port_connected_method_status status;
 682         PyObject *py_comp = NULL;
 683         PyObject *py_self_port_ptr = NULL;
 684         PyObject *py_other_port_ptr = NULL;
 685         PyObject *py_method_result = NULL;
 686
 687         py_comp = bt_self_component_get_data(self_component);
 688         BT_ASSERT(py_comp);
 689         py_self_port_ptr = SWIG_NewPointerObj(SWIG_as_voidptr(self_component_port),
 690                 self_component_port_swig_type, 0);
 691         if (!py_self_port_ptr) {
 692                 BT_LOGF_STR("Failed to create a SWIG pointer object.");
 693                 status = __BT_FUNC_STATUS_MEMORY_ERROR;
 694                 goto end;
 695         }
 696
 697         py_other_port_ptr = SWIG_NewPointerObj(SWIG_as_voidptr(other_port),
 698                 other_port_swig_type, 0);
 699         if (!py_other_port_ptr) {
 700                 BT_LOGF_STR("Failed to create a SWIG pointer object.");
 701                 status = __BT_FUNC_STATUS_MEMORY_ERROR;
 702                 goto end;       }
 703
 704         py_method_result = PyObject_CallMethod(py_comp,
 705                 "_bt_port_connected_from_native", "(OiO)", py_self_port_ptr,
 706                 self_component_port_type, py_other_port_ptr);
 707         BT_ASSERT(!py_method_result || py_method_result == Py_None);
 708         status = py_exc_to_status_component(self_component);
 709
 710 end:
 711         Py_XDECREF(py_self_port_ptr);
 712         Py_XDECREF(py_other_port_ptr);
 713         Py_XDECREF(py_method_result);
 714         return status;
 715 }
 716
 717 static
 718 bt_component_class_port_connected_method_status
 719 component_class_source_output_port_connected(
 720                 bt_self_component_source *self_component_source,
 721                 bt_self_component_port_output *self_component_port_output,
 722                 const bt_port_input *other_port_input)
 723 {
 724         bt_self_component *self_component = bt_self_component_source_as_self_component(self_component_source);
 725
 726         return component_class_port_connected(
 727                 self_component,
 728                 self_component_port_output,
 729                 SWIGTYPE_p_bt_self_component_port_output,
 730                 BT_PORT_TYPE_OUTPUT,
 731                 other_port_input,
 732                 SWIGTYPE_p_bt_port_input);
 733 }
 734
 735 static
 736 bt_component_class_port_connected_method_status
 737 component_class_filter_input_port_connected(
 738                 bt_self_component_filter *self_component_filter,
 739                 bt_self_component_port_input *self_component_port_input,
 740                 const bt_port_output *other_port_output)
 741 {
 742         bt_self_component *self_component = bt_self_component_filter_as_self_component(self_component_filter);
 743
 744         return component_class_port_connected(
 745                 self_component,
 746                 self_component_port_input,
 747                 SWIGTYPE_p_bt_self_component_port_input,
 748                 BT_PORT_TYPE_INPUT,
 749                 other_port_output,
 750                 SWIGTYPE_p_bt_port_output);
 751 }
 752
 753 static
 754 bt_component_class_port_connected_method_status
 755 component_class_filter_output_port_connected(
 756                 bt_self_component_filter *self_component_filter,
 757                 bt_self_component_port_output *self_component_port_output,
 758                 const bt_port_input *other_port_input)
 759 {
 760         bt_self_component *self_component = bt_self_component_filter_as_self_component(self_component_filter);
 761
 762         return component_class_port_connected(
 763                 self_component,
 764                 self_component_port_output,
 765                 SWIGTYPE_p_bt_self_component_port_output,
 766                 BT_PORT_TYPE_OUTPUT,
 767                 other_port_input,
 768                 SWIGTYPE_p_bt_port_input);
 769 }
 770
 771 static
 772 bt_component_class_port_connected_method_status
 773 component_class_sink_input_port_connected(
 774                 bt_self_component_sink *self_component_sink,
 775                 bt_self_component_port_input *self_component_port_input,
 776                 const bt_port_output *other_port_output)
 777 {
 778         bt_self_component *self_component = bt_self_component_sink_as_self_component(self_component_sink);
 779
 780         return component_class_port_connected(
 781                 self_component,
 782                 self_component_port_input,
 783                 SWIGTYPE_p_bt_self_component_port_input,
 784                 BT_PORT_TYPE_INPUT,
 785                 other_port_output,
 786                 SWIGTYPE_p_bt_port_output);
 787 }
 788
 789 static
 790 bt_component_class_sink_graph_is_configured_method_status
 791 component_class_sink_graph_is_configured(
 792                 bt_self_component_sink *self_component_sink)
 793 {
 794         PyObject *py_comp = NULL;
 795         PyObject *py_method_result = NULL;
 796         bt_component_class_sink_graph_is_configured_method_status status = __BT_FUNC_STATUS_OK;
 797         bt_self_component *self_component = bt_self_component_sink_as_self_component(self_component_sink);
 798
 799         py_comp = bt_self_component_get_data(self_component);
 800         py_method_result = PyObject_CallMethod(py_comp,
 801                 "_bt_graph_is_configured_from_native", NULL);
 802         BT_ASSERT(!py_method_result || py_method_result == Py_None);
 803         status = py_exc_to_status_component(self_component);
 804         Py_XDECREF(py_method_result);
 805         return status;
 806 }
 807
 808 static
 809 bt_component_class_query_method_status component_class_query(
 810                 const bt_component_class *component_class,
 811                 bt_self_component_class *self_component_class,
 812                 const bt_query_executor *query_executor,
 813                 const char *object, const bt_value *params,
 814                 bt_logging_level log_level,
 815                 const bt_value **result)
 816 {
 817         PyObject *py_cls = NULL;
 818         PyObject *py_params_ptr = NULL;
 819         PyObject *py_query_exec_ptr = NULL;
 820         PyObject *py_query_func = NULL;
 821         PyObject *py_object = NULL;
 822         PyObject *py_results_addr = NULL;
 823         bt_component_class_query_method_status status = __BT_FUNC_STATUS_OK;
 824
 825         py_cls = lookup_cc_ptr_to_py_cls(component_class);
 826         if (!py_cls) {
 827                 BT_LOGE("Cannot find Python class associated to native component class: "
 828                         "comp-cls-addr=%p", component_class);
 829                 goto error;
 830         }
 831
 832         py_params_ptr = SWIG_NewPointerObj(SWIG_as_voidptr(params),
 833                 SWIGTYPE_p_bt_value, 0);
 834         if (!py_params_ptr) {
 835                 BT_LOGE_STR("Failed to create a SWIG pointer object.");
 836                 goto error;
 837         }
 838
 839         py_query_exec_ptr = SWIG_NewPointerObj(SWIG_as_voidptr(query_executor),
 840                 SWIGTYPE_p_bt_query_executor, 0);
 841         if (!py_query_exec_ptr) {
 842                 BT_LOGE_STR("Failed to create a SWIG pointer object.");
 843                 goto error;
 844         }
 845
 846         py_object = SWIG_FromCharPtr(object);
 847         if (!py_object) {
 848                 BT_LOGE_STR("Failed to create a Python string.");
 849                 goto error;
 850         }
 851
 852         py_results_addr = PyObject_CallMethod(py_cls,
 853                 "_bt_query_from_native", "(OOOi)", py_query_exec_ptr,
 854                 py_object, py_params_ptr, (int) log_level);
 855         if (!py_results_addr) {
 856                 BT_LOGW("Failed to call Python class's _bt_query_from_native() method: "
 857                         "py-cls-addr=%p", py_cls);
 858                 status = py_exc_to_status_component_class(self_component_class);
 859                 goto end;
 860         }
 861
 862         /*
 863          * The returned object, on success, is an integer object
 864          * (PyLong) containing the address of a BT value object (new
 865          * reference).
 866          */
 867         *result = PyLong_AsVoidPtr(py_results_addr);
 868         BT_ASSERT(!PyErr_Occurred());
 869         BT_ASSERT(*result);
 870         goto end;
 871
 872 error:
 873         PyErr_Clear();
 874         status = __BT_FUNC_STATUS_ERROR;
 875
 876 end:
 877         Py_XDECREF(py_params_ptr);
 878         Py_XDECREF(py_query_exec_ptr);
 879         Py_XDECREF(py_query_func);
 880         Py_XDECREF(py_object);
 881         Py_XDECREF(py_results_addr);
 882         return status;
 883 }
 884
 885 static
 886 bt_component_class_query_method_status component_class_source_query(
 887                 bt_self_component_class_source *self_component_class_source,
 888                 const bt_query_executor *query_executor,
 889                 const char *object, const bt_value *params,
 890                 bt_logging_level log_level,
 891                 const bt_value **result)
 892 {
 893         const bt_component_class_source *component_class_source = bt_self_component_class_source_as_component_class_source(self_component_class_source);
 894         const bt_component_class *component_class = bt_component_class_source_as_component_class_const(component_class_source);
 895         bt_self_component_class *self_component_class = bt_self_component_class_source_as_self_component_class(self_component_class_source);
 896
 897         return component_class_query(component_class, self_component_class, query_executor, object, params, log_level, result);
 898 }
 899
 900 static
 901 bt_component_class_query_method_status component_class_filter_query(
 902                 bt_self_component_class_filter *self_component_class_filter,
 903                 const bt_query_executor *query_executor,
 904                 const char *object, const bt_value *params,
 905                 bt_logging_level log_level,
 906                 const bt_value **result)
 907 {
 908         const bt_component_class_filter *component_class_filter = bt_self_component_class_filter_as_component_class_filter(self_component_class_filter);
 909         const bt_component_class *component_class = bt_component_class_filter_as_component_class_const(component_class_filter);
 910         bt_self_component_class *self_component_class = bt_self_component_class_filter_as_self_component_class(self_component_class_filter);
 911
 912         return component_class_query(component_class, self_component_class, query_executor, object, params, log_level, result);
 913 }
 914
 915 static
 916 bt_component_class_query_method_status component_class_sink_query(
 917                 bt_self_component_class_sink *self_component_class_sink,
 918                 const bt_query_executor *query_executor,
 919                 const char *object, const bt_value *params,
 920                 bt_logging_level log_level,
 921                 const bt_value **result)
 922 {
 923         const bt_component_class_sink *component_class_sink = bt_self_component_class_sink_as_component_class_sink(self_component_class_sink);
 924         const bt_component_class *component_class = bt_component_class_sink_as_component_class_const(component_class_sink);
 925         bt_self_component_class *self_component_class = bt_self_component_class_sink_as_self_component_class(self_component_class_sink);
 926
 927         return component_class_query(component_class, self_component_class, query_executor, object, params, log_level, result);
 928 }
 929
 930 static
 931 bt_component_class_message_iterator_init_method_status
 932 component_class_message_iterator_init(
 933                 bt_self_message_iterator *self_message_iterator,
 934                 bt_self_component *self_component,
 935                 bt_self_component_port_output *self_component_port_output)
 936 {
 937         bt_component_class_message_iterator_init_method_status status = __BT_FUNC_STATUS_OK;
 938         PyObject *py_comp_cls = NULL;
 939         PyObject *py_iter_cls = NULL;
 940         PyObject *py_iter_ptr = NULL;
 941         PyObject *py_component_port_output_ptr = NULL;
 942         PyObject *py_init_method_result = NULL;
 943         PyObject *py_iter = NULL;
 944         PyObject *py_comp;
 945
 946         py_comp = bt_self_component_get_data(self_component);
 947
 948         /* Find user's Python message iterator class */
 949         py_comp_cls = PyObject_GetAttrString(py_comp, "__class__");
 950         if (!py_comp_cls) {
 951                 BT_LOGE_STR("Cannot get Python object's `__class__` attribute.");
 952                 goto python_error;
 953         }
 954
 955         py_iter_cls = PyObject_GetAttrString(py_comp_cls, "_iter_cls");
 956         if (!py_iter_cls) {
 957                 BT_LOGE_STR("Cannot get Python class's `_iter_cls` attribute.");
 958                 goto python_error;
 959         }
 960
 961         py_iter_ptr = SWIG_NewPointerObj(SWIG_as_voidptr(self_message_iterator),
 962                 SWIGTYPE_p_bt_self_message_iterator, 0);
 963         if (!py_iter_ptr) {
 964                 const char *err = "Failed to create a SWIG pointer object.";
 965
 966                 BT_LOGE_STR(err);
 967                 BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_MESSAGE_ITERATOR(
 968                         self_message_iterator, err);
 969                 goto error;
 970         }
 971
 972         /*
 973          * Create object with borrowed native message iterator
 974          * reference:
 975          *
 976          *     py_iter = py_iter_cls.__new__(py_iter_cls, py_iter_ptr)
 977          */
 978         py_iter = PyObject_CallMethod(py_iter_cls, "__new__",
 979                 "(OO)", py_iter_cls, py_iter_ptr);
 980         if (!py_iter) {
 981                 BT_LOGE("Failed to call Python class's __new__() method: "
 982                         "py-cls-addr=%p", py_iter_cls);
 983                 goto python_error;
 984         }
 985
 986         /*
 987          * Initialize object:
 988          *
 989          *     py_iter.__init__(self_output_port)
 990          *
 991          * through the _init_for_native helper static method.
 992          *
 993          * At this point, py_iter._ptr is set, so this initialization
 994          * function has access to self._component (which gives it the
 995          * user Python component object from which the iterator was
 996          * created).
 997          */
 998         py_component_port_output_ptr = SWIG_NewPointerObj(
 999                 SWIG_as_voidptr(self_component_port_output),
1000                 SWIGTYPE_p_bt_self_component_port_output, 0);
1001         if (!py_component_port_output_ptr) {
1002                 const char *err = "Failed to create a SWIG pointer object.";
1003
1004                 BT_LOGE_STR(err);
1005                 BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_MESSAGE_ITERATOR(
1006                         self_message_iterator, err);
1007                 goto error;
1008         }
1009
1010         py_init_method_result = PyObject_CallMethod(py_iter,
1011                 "_bt_init_from_native", "O", py_component_port_output_ptr);
1012         if (!py_init_method_result) {
1013                 BT_LOGE_STR("User's __init__() method failed:");
1014                 goto python_error;
1015         }
1016
1017         /*
1018          * Since the Python code can never instantiate a user-defined
1019          * message iterator class, the native message iterator
1020          * object does NOT belong to a user Python message iterator
1021          * object (borrowed reference). However this Python object is
1022          * owned by this native message iterator object.
1023          *
1024          * In the Python world, the lifetime of the native message
1025          * iterator is managed by a _GenericMessageIterator
1026          * instance:
1027          *
1028          *     _GenericMessageIterator instance:
1029          *         owns a native bt_message_iterator object (iter)
1030          *             owns a _UserMessageIterator instance (py_iter)
1031          *                 self._ptr is a borrowed reference to the
1032          *                 native bt_private_connection_private_message_iterator
1033          *                 object (iter)
1034          */
1035         bt_self_message_iterator_set_data(self_message_iterator, py_iter);
1036         py_iter = NULL;
1037         goto end;
1038
1039 python_error:
1040         /* Handling of errors that cause a Python exception to be set. */
1041         status = py_exc_to_status_message_iterator(self_message_iterator);
1042         BT_ASSERT(status != __BT_FUNC_STATUS_OK);
1043         goto end;
1044
1045 error:
1046         /* Handling of errors that don't cause a Python exception to be set. */
1047         status = __BT_FUNC_STATUS_ERROR;
1048
1049 end:
1050         BT_ASSERT(!PyErr_Occurred());
1051
1052         Py_XDECREF(py_comp_cls);
1053         Py_XDECREF(py_iter_cls);
1054         Py_XDECREF(py_iter_ptr);
1055         Py_XDECREF(py_component_port_output_ptr);
1056         Py_XDECREF(py_init_method_result);
1057         Py_XDECREF(py_iter);
1058         return status;
1059 }
1060
1061 static
1062 bt_component_class_message_iterator_init_method_status
1063 component_class_source_message_iterator_init(
1064                 bt_self_message_iterator *self_message_iterator,
1065                 bt_self_component_source *self_component_source,
1066                 bt_self_component_port_output *self_component_port_output)
1067 {
1068         bt_self_component *self_component = bt_self_component_source_as_self_component(self_component_source);
1069
1070         return component_class_message_iterator_init(self_message_iterator, self_component, self_component_port_output);
1071 }
1072
1073 static
1074 bt_component_class_message_iterator_init_method_status
1075 component_class_filter_message_iterator_init(
1076                 bt_self_message_iterator *self_message_iterator,
1077                 bt_self_component_filter *self_component_filter,
1078                 bt_self_component_port_output *self_component_port_output)
1079 {
1080         bt_self_component *self_component = bt_self_component_filter_as_self_component(self_component_filter);
1081
1082         return component_class_message_iterator_init(self_message_iterator, self_component, self_component_port_output);
1083 }
1084
1085 static
1086 void component_class_message_iterator_finalize(
1087                 bt_self_message_iterator *message_iterator)
1088 {
1089         PyObject *py_message_iter = bt_self_message_iterator_get_data(message_iterator);
1090         PyObject *py_method_result = NULL;
1091
1092         BT_ASSERT(py_message_iter);
1093
1094         /* Call user's _finalize() method */
1095         py_method_result = PyObject_CallMethod(py_message_iter,
1096                 "_finalize", NULL);
1097
1098         if (PyErr_Occurred()) {
1099                 BT_LOGW("User's _finalize() method raised an exception: ignoring:");
1100                 logw_exception();
1101         }
1102
1103         /*
1104          * Ignore any exception raised by the _finalize() method because
1105          * it won't change anything at this point: the component is
1106          * being destroyed anyway.
1107          */
1108         PyErr_Clear();
1109         Py_XDECREF(py_method_result);
1110         Py_DECREF(py_message_iter);
1111 }
1112
1113 /* Valid for both sources and filters. */
1114
1115 static
1116 bt_component_class_message_iterator_next_method_status
1117 component_class_message_iterator_next(
1118                 bt_self_message_iterator *message_iterator,
1119                 bt_message_array_const msgs, uint64_t capacity,
1120                 uint64_t *count)
1121 {
1122         bt_component_class_message_iterator_next_method_status status = __BT_FUNC_STATUS_OK;
1123         PyObject *py_message_iter = bt_self_message_iterator_get_data(message_iterator);
1124         PyObject *py_method_result = NULL;
1125
1126         BT_ASSERT(py_message_iter);
1127         py_method_result = PyObject_CallMethod(py_message_iter,
1128                 "_bt_next_from_native", NULL);
1129         if (!py_method_result) {
1130                 status = py_exc_to_status_message_iterator(message_iterator);
1131                 BT_ASSERT(status != __BT_FUNC_STATUS_OK);
1132                 goto end;
1133         }
1134
1135         /*
1136          * The returned object, on success, is an integer object
1137          * (PyLong) containing the address of a native message
1138          * object (which is now ours).
1139          */
1140         msgs[0] = PyLong_AsVoidPtr(py_method_result);
1141         *count = 1;
1142
1143         /* Clear potential overflow error; should never happen */
1144         BT_ASSERT(!PyErr_Occurred());
1145         goto end;
1146
1147 end:
1148         Py_XDECREF(py_method_result);
1149         return status;
1150 }
1151
1152 static
1153 bt_component_class_sink_consume_method_status
1154 component_class_sink_consume(bt_self_component_sink *self_component_sink)
1155 {
1156         bt_self_component *self_component = bt_self_component_sink_as_self_component(self_component_sink);
1157         PyObject *py_comp = bt_self_component_get_data(self_component);
1158         PyObject *py_method_result = NULL;
1159         bt_component_class_sink_consume_method_status status;
1160
1161         BT_ASSERT(py_comp);
1162         py_method_result = PyObject_CallMethod(py_comp,
1163                 "_consume", NULL);
1164         status = py_exc_to_status_component(self_component);
1165         if (!py_method_result && status == __BT_FUNC_STATUS_OK) {
1166                 /* Pretty sure this should never happen, but just in case */
1167                 BT_LOGE("User's _consume() method failed without raising an exception: "
1168                         "status=%d", status);
1169                 status = __BT_FUNC_STATUS_ERROR;
1170         }
1171
1172         Py_XDECREF(py_method_result);
1173         return status;
1174 }
1175
1176 static
1177 int component_class_set_help_and_desc(
1178                 bt_component_class *component_class,
1179                 const char *description, const char *help)
1180 {
1181         int ret;
1182
1183         if (description) {
1184                 ret = bt_component_class_set_description(component_class, description);
1185                 if (ret) {
1186                         BT_LOGE("Cannot set component class's description: "
1187                                 "comp-cls-addr=%p", component_class);
1188                         goto end;
1189                 }
1190         }
1191
1192         if (help) {
1193                 ret = bt_component_class_set_help(component_class, help);
1194                 if (ret) {
1195                         BT_LOGE("Cannot set component class's help text: "
1196                                 "comp-cls-addr=%p", component_class);
1197                         goto end;
1198                 }
1199         }
1200
1201         ret = 0;
1202
1203 end:
1204         return ret;
1205 }
1206
1207 static
1208 bt_component_class_source *bt_bt2_component_class_source_create(
1209                 PyObject *py_cls, const char *name, const char *description,
1210                 const char *help)
1211 {
1212         bt_component_class_source *component_class_source;
1213         bt_component_class *component_class;
1214         int ret;
1215
1216         BT_ASSERT(py_cls);
1217         component_class_source = bt_component_class_source_create(name,
1218                 component_class_message_iterator_next);
1219         if (!component_class_source) {
1220                 BT_LOGE_STR("Cannot create source component class.");
1221                 goto end;
1222         }
1223
1224         component_class = bt_component_class_source_as_component_class(component_class_source);
1225
1226         if (component_class_set_help_and_desc(component_class, description, help)) {
1227                 goto end;
1228         }
1229
1230         ret = bt_component_class_source_set_init_method(component_class_source, component_class_source_init);
1231         BT_ASSERT(ret == 0);
1232         ret = bt_component_class_source_set_finalize_method(component_class_source, component_class_source_finalize);
1233         BT_ASSERT(ret == 0);
1234         ret = bt_component_class_source_set_message_iterator_can_seek_beginning_method(component_class_source,
1235                 component_class_can_seek_beginning);
1236         BT_ASSERT(ret == 0);
1237         ret = bt_component_class_source_set_message_iterator_seek_beginning_method(component_class_source,
1238                 component_class_seek_beginning);
1239         BT_ASSERT(ret == 0);
1240         ret = bt_component_class_source_set_output_port_connected_method(component_class_source,
1241                 component_class_source_output_port_connected);
1242         BT_ASSERT(ret == 0);
1243         ret = bt_component_class_source_set_query_method(component_class_source, component_class_source_query);
1244         BT_ASSERT(ret == 0);
1245         ret = bt_component_class_source_set_message_iterator_init_method(
1246                 component_class_source, component_class_source_message_iterator_init);
1247         BT_ASSERT(ret == 0);
1248         ret = bt_component_class_source_set_message_iterator_finalize_method(
1249                 component_class_source, component_class_message_iterator_finalize);
1250         BT_ASSERT(ret == 0);
1251         register_cc_ptr_to_py_cls(component_class, py_cls);
1252
1253 end:
1254         return component_class_source;
1255 }
1256
1257 static
1258 bt_component_class_filter *bt_bt2_component_class_filter_create(
1259                 PyObject *py_cls, const char *name, const char *description,
1260                 const char *help)
1261 {
1262         bt_component_class *component_class;
1263         bt_component_class_filter *component_class_filter;
1264         int ret;
1265
1266         BT_ASSERT(py_cls);
1267         component_class_filter = bt_component_class_filter_create(name,
1268                 component_class_message_iterator_next);
1269         if (!component_class_filter) {
1270                 BT_LOGE_STR("Cannot create filter component class.");
1271                 goto end;
1272         }
1273
1274         component_class = bt_component_class_filter_as_component_class(component_class_filter);
1275
1276         if (component_class_set_help_and_desc(component_class, description, help)) {
1277                 goto end;
1278         }
1279
1280         ret = bt_component_class_filter_set_init_method(component_class_filter, component_class_filter_init);
1281         BT_ASSERT(ret == 0);
1282         ret = bt_component_class_filter_set_finalize_method (component_class_filter, component_class_filter_finalize);
1283         BT_ASSERT(ret == 0);
1284         ret = bt_component_class_filter_set_message_iterator_can_seek_beginning_method(component_class_filter,
1285                 component_class_can_seek_beginning);
1286         BT_ASSERT(ret == 0);
1287         ret = bt_component_class_filter_set_message_iterator_seek_beginning_method(component_class_filter,
1288                 component_class_seek_beginning);
1289         BT_ASSERT(ret == 0);
1290         ret = bt_component_class_filter_set_input_port_connected_method(component_class_filter,
1291                 component_class_filter_input_port_connected);
1292         BT_ASSERT(ret == 0);
1293         ret = bt_component_class_filter_set_output_port_connected_method(component_class_filter,
1294                 component_class_filter_output_port_connected);
1295         BT_ASSERT(ret == 0);
1296         ret = bt_component_class_filter_set_query_method(component_class_filter, component_class_filter_query);
1297         BT_ASSERT(ret == 0);
1298         ret = bt_component_class_filter_set_message_iterator_init_method(
1299                 component_class_filter, component_class_filter_message_iterator_init);
1300         BT_ASSERT(ret == 0);
1301         ret = bt_component_class_filter_set_message_iterator_finalize_method(
1302                 component_class_filter, component_class_message_iterator_finalize);
1303         BT_ASSERT(ret == 0);
1304         register_cc_ptr_to_py_cls(component_class, py_cls);
1305
1306 end:
1307         return component_class_filter;
1308 }
1309
1310 static
1311 bt_component_class_sink *bt_bt2_component_class_sink_create(
1312                 PyObject *py_cls, const char *name, const char *description,
1313                 const char *help)
1314 {
1315         bt_component_class_sink *component_class_sink;
1316         bt_component_class *component_class;
1317         int ret;
1318
1319         BT_ASSERT(py_cls);
1320         component_class_sink = bt_component_class_sink_create(name, component_class_sink_consume);
1321
1322         if (!component_class_sink) {
1323                 BT_LOGE_STR("Cannot create sink component class.");
1324                 goto end;
1325         }
1326
1327         component_class = bt_component_class_sink_as_component_class(component_class_sink);
1328
1329         if (component_class_set_help_and_desc(component_class, description, help)) {
1330                 goto end;
1331         }
1332
1333         ret = bt_component_class_sink_set_init_method(component_class_sink, component_class_sink_init);
1334         BT_ASSERT(ret == 0);
1335         ret = bt_component_class_sink_set_finalize_method(component_class_sink, component_class_sink_finalize);
1336         BT_ASSERT(ret == 0);
1337         ret = bt_component_class_sink_set_input_port_connected_method(component_class_sink,
1338                 component_class_sink_input_port_connected);
1339         BT_ASSERT(ret == 0);
1340         ret = bt_component_class_sink_set_graph_is_configured_method(component_class_sink,
1341                 component_class_sink_graph_is_configured);
1342         BT_ASSERT(ret == 0);
1343         ret = bt_component_class_sink_set_query_method(component_class_sink, component_class_sink_query);
1344         BT_ASSERT(ret == 0);
1345         register_cc_ptr_to_py_cls(component_class, py_cls);
1346
1347 end:
1348         return component_class_sink;
1349 }
1350 %}
1351
1352 struct bt_component_class_source *bt_bt2_component_class_source_create(
1353                 PyObject *py_cls, const char *name, const char *description,
1354                 const char *help);
1355 struct bt_component_class_filter *bt_bt2_component_class_filter_create(
1356                 PyObject *py_cls, const char *name, const char *description,
1357                 const char *help);
1358 struct bt_component_class_sink *bt_bt2_component_class_sink_create(
1359                 PyObject *py_cls, const char *name, const char *description,
1360                 const char *help);
1361 void bt_bt2_cc_init_from_bt2(void);
1362 void bt_bt2_cc_exit_handler(void);