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