src/lib/graph/iterator.c

   1 /*
   2  * SPDX-License-Identifier: MIT
   3  *
   4  * Copyright 2017-2018 Philippe Proulx <pproulx@efficios.com>
   5  * Copyright 2015 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   6  */
   7
   8 #define BT_LOG_TAG "LIB/MSG-ITER"
   9 #include "lib/logging.h"
  10
  11 #include "compat/compiler.h"
  12 #include "compat/glib.h"
  13 #include "lib/trace-ir/clock-class.h"
  14 #include "lib/trace-ir/clock-snapshot.h"
  15 #include <babeltrace2/trace-ir/field.h>
  16 #include <babeltrace2/trace-ir/event.h>
  17 #include "lib/trace-ir/event.h"
  18 #include <babeltrace2/trace-ir/packet.h>
  19 #include "lib/trace-ir/packet.h"
  20 #include "lib/trace-ir/stream.h"
  21 #include <babeltrace2/trace-ir/clock-class.h>
  22 #include <babeltrace2/trace-ir/stream-class.h>
  23 #include <babeltrace2/trace-ir/stream.h>
  24 #include <babeltrace2/graph/connection.h>
  25 #include <babeltrace2/graph/component.h>
  26 #include <babeltrace2/graph/message.h>
  27 #include <babeltrace2/graph/self-component.h>
  28 #include <babeltrace2/graph/port.h>
  29 #include <babeltrace2/graph/graph.h>
  30 #include <babeltrace2/graph/message-iterator.h>
  31 #include <babeltrace2/types.h>
  32 #include "common/assert.h"
  33 #include "lib/assert-cond.h"
  34 #include <stdint.h>
  35 #include <inttypes.h>
  36 #include <stdbool.h>
  37 #include <stdlib.h>
  38
  39 #include "component-class.h"
  40 #include "component.h"
  41 #include "connection.h"
  42 #include "graph.h"
  43 #include "message-iterator-class.h"
  44 #include "message/discarded-items.h"
  45 #include "message/event.h"
  46 #include "message/iterator.h"
  47 #include "message/message.h"
  48 #include "message/message-iterator-inactivity.h"
  49 #include "message/stream.h"
  50 #include "message/packet.h"
  51 #include "lib/func-status.h"
  52
  53 /*
  54  * TODO: Use graph's state (number of active iterators, etc.) and
  55  * possibly system specifications to make a better guess than this.
  56  */
  57 #define MSG_BATCH_SIZE  15
  58
  59 #define BT_ASSERT_PRE_ITER_HAS_STATE_TO_SEEK(_iter)                     \
  60         BT_ASSERT_PRE("has-state-to-seek",                              \
  61                 (_iter)->state == BT_MESSAGE_ITERATOR_STATE_ACTIVE ||   \
  62                 (_iter)->state == BT_MESSAGE_ITERATOR_STATE_ENDED ||    \
  63                 (_iter)->state == BT_MESSAGE_ITERATOR_STATE_LAST_SEEKING_RETURNED_AGAIN || \
  64                 (_iter)->state == BT_MESSAGE_ITERATOR_STATE_LAST_SEEKING_RETURNED_ERROR, \
  65                 "Message iterator is in the wrong state: %!+i", (_iter))
  66
  67 #ifdef BT_DEV_MODE
  68 struct per_stream_state
  69 {
  70         bt_packet *cur_packet;
  71
  72         /* Bit mask of expected message types. */
  73         guint expected_msg_types;
  74 };
  75 #endif
  76
  77 static void
  78 clear_per_stream_state (struct bt_message_iterator *iterator)
  79 {
  80 #ifdef BT_DEV_MODE
  81         g_hash_table_remove_all(iterator->per_stream_state);
  82 #else
  83         BT_USE_EXPR(iterator);
  84 #endif
  85 }
  86
  87 static inline
  88 void set_msg_iterator_state(struct bt_message_iterator *iterator,
  89                 enum bt_message_iterator_state state)
  90 {
  91         BT_ASSERT_DBG(iterator);
  92         BT_LIB_LOGD("Updating message iterator's state: new-state=%s",
  93                 bt_message_iterator_state_string(state));
  94         iterator->state = state;
  95 }
  96
  97 static
  98 void bt_message_iterator_destroy(struct bt_object *obj)
  99 {
 100         struct bt_message_iterator *iterator;
 101
 102         BT_ASSERT(obj);
 103
 104         /*
 105          * The message iterator's reference count is 0 if we're
 106          * here. Increment it to avoid a double-destroy (possibly
 107          * infinitely recursive). This could happen for example if the
 108          * message iterator's finalization function does
 109          * bt_object_get_ref() (or anything that causes
 110          * bt_object_get_ref() to be called) on itself (ref. count goes
 111          * from 0 to 1), and then bt_object_put_ref(): the reference
 112          * count would go from 1 to 0 again and this function would be
 113          * called again.
 114          */
 115         obj->ref_count++;
 116         iterator = (void *) obj;
 117         BT_LIB_LOGI("Destroying self component input port message iterator object: "
 118                 "%!+i", iterator);
 119         bt_message_iterator_try_finalize(iterator);
 120
 121         if (iterator->connection) {
 122                 /*
 123                  * Remove ourself from the originating connection so
 124                  * that it does not try to finalize a dangling pointer
 125                  * later.
 126                  */
 127                 bt_connection_remove_iterator(iterator->connection, iterator);
 128                 iterator->connection = NULL;
 129         }
 130
 131         if (iterator->auto_seek.msgs) {
 132                 while (!g_queue_is_empty(iterator->auto_seek.msgs)) {
 133                         bt_object_put_ref_no_null_check(
 134                                 g_queue_pop_tail(iterator->auto_seek.msgs));
 135                 }
 136
 137                 g_queue_free(iterator->auto_seek.msgs);
 138                 iterator->auto_seek.msgs = NULL;
 139         }
 140
 141         if (iterator->upstream_msg_iters) {
 142                 /*
 143                  * At this point the message iterator is finalized, so
 144                  * it's detached from any upstream message iterator.
 145                  */
 146                 BT_ASSERT(iterator->upstream_msg_iters->len == 0);
 147                 g_ptr_array_free(iterator->upstream_msg_iters, TRUE);
 148                 iterator->upstream_msg_iters = NULL;
 149         }
 150
 151         if (iterator->msgs) {
 152                 g_ptr_array_free(iterator->msgs, TRUE);
 153                 iterator->msgs = NULL;
 154         }
 155
 156 #ifdef BT_DEV_MODE
 157         g_hash_table_destroy(iterator->per_stream_state);
 158 #endif
 159
 160         g_free(iterator);
 161 }
 162
 163 void bt_message_iterator_try_finalize(
 164                 struct bt_message_iterator *iterator)
 165 {
 166         uint64_t i;
 167         bool call_user_finalize = true;
 168
 169         BT_ASSERT(iterator);
 170
 171         switch (iterator->state) {
 172         case BT_MESSAGE_ITERATOR_STATE_NON_INITIALIZED:
 173                 /*
 174                  * If this function is called while the iterator is in the
 175                  * NON_INITIALIZED state, it means the user initialization
 176                  * method has either not been called, or has failed.  We
 177                  * therefore don't want to call the user finalization method.
 178                  * However, the initialization method might have created some
 179                  * upstream message iterators before failing, so we want to
 180                  * execute the rest of this function, which unlinks the related
 181                  * iterators.
 182                  */
 183                 call_user_finalize = false;
 184                 break;
 185         case BT_MESSAGE_ITERATOR_STATE_FINALIZED:
 186                 /* Already finalized */
 187                 BT_LIB_LOGD("Not finalizing message iterator: already finalized: "
 188                         "%!+i", iterator);
 189                 goto end;
 190         case BT_MESSAGE_ITERATOR_STATE_FINALIZING:
 191                 /* Finalizing */
 192                 BT_LIB_LOGF("Message iterator is already being finalized: "
 193                         "%!+i", iterator);
 194                 bt_common_abort();
 195         default:
 196                 break;
 197         }
 198
 199         BT_LIB_LOGD("Finalizing message iterator: %!+i", iterator);
 200         set_msg_iterator_state(iterator,
 201                 BT_MESSAGE_ITERATOR_STATE_FINALIZING);
 202         BT_ASSERT(iterator->upstream_component);
 203
 204         /* Call user-defined destroy method */
 205         if (call_user_finalize) {
 206                 typedef void (*method_t)(void *);
 207                 method_t method;
 208                 struct bt_component_class *comp_class =
 209                         iterator->upstream_component->class;
 210                 struct bt_component_class_with_iterator_class *class_with_iter_class;
 211
 212                 BT_ASSERT(bt_component_class_has_message_iterator_class(comp_class));
 213                 class_with_iter_class = container_of(comp_class,
 214                         struct bt_component_class_with_iterator_class, parent);
 215                 method = (method_t) class_with_iter_class->msg_iter_cls->methods.finalize;
 216
 217                 if (method) {
 218                         const bt_error *saved_error;
 219
 220                         saved_error = bt_current_thread_take_error();
 221
 222                         BT_LIB_LOGD("Calling user's finalization method: %!+i",
 223                                 iterator);
 224                         method(iterator);
 225                         BT_ASSERT_POST_NO_ERROR("bt_message_iterator_class_finalize_method");
 226
 227                         if (saved_error) {
 228                                 BT_CURRENT_THREAD_MOVE_ERROR_AND_RESET(saved_error);
 229                         }
 230                 }
 231         }
 232
 233         /* Detach upstream message iterators */
 234         for (i = 0; i < iterator->upstream_msg_iters->len; i++) {
 235                 struct bt_message_iterator *upstream_msg_iter =
 236                         iterator->upstream_msg_iters->pdata[i];
 237
 238                 upstream_msg_iter->downstream_msg_iter = NULL;
 239         }
 240
 241         g_ptr_array_set_size(iterator->upstream_msg_iters, 0);
 242
 243         /* Detach downstream message iterator */
 244         if (iterator->downstream_msg_iter) {
 245                 gboolean existed;
 246
 247                 BT_ASSERT(iterator->downstream_msg_iter->upstream_msg_iters);
 248                 existed = g_ptr_array_remove_fast(
 249                         iterator->downstream_msg_iter->upstream_msg_iters,
 250                         iterator);
 251                 BT_ASSERT(existed);
 252         }
 253
 254         iterator->upstream_component = NULL;
 255         iterator->upstream_port = NULL;
 256         set_msg_iterator_state(iterator,
 257                 BT_MESSAGE_ITERATOR_STATE_FINALIZED);
 258         BT_LIB_LOGD("Finalized message iterator: %!+i", iterator);
 259
 260 end:
 261         return;
 262 }
 263
 264 void bt_message_iterator_set_connection(
 265                 struct bt_message_iterator *iterator,
 266                 struct bt_connection *connection)
 267 {
 268         BT_ASSERT(iterator);
 269         iterator->connection = connection;
 270         BT_LIB_LOGI("Set message iterator's connection: "
 271                 "%![iter-]+i, %![conn-]+x", iterator, connection);
 272 }
 273
 274 static
 275 enum bt_message_iterator_can_seek_beginning_status can_seek_ns_from_origin_true(
 276                 struct bt_message_iterator *iterator __attribute__((unused)),
 277                 int64_t ns_from_origin __attribute__((unused)),
 278                 bt_bool *can_seek)
 279 {
 280         *can_seek = BT_TRUE;
 281
 282         return BT_FUNC_STATUS_OK;
 283 }
 284
 285 static
 286 enum bt_message_iterator_can_seek_beginning_status can_seek_beginning_true(
 287                 struct bt_message_iterator *iterator __attribute__((unused)),
 288                 bt_bool *can_seek)
 289 {
 290         *can_seek = BT_TRUE;
 291
 292         return BT_FUNC_STATUS_OK;
 293 }
 294
 295 static
 296 int create_self_component_input_port_message_iterator(
 297                 struct bt_self_message_iterator *self_downstream_msg_iter,
 298                 struct bt_self_component_port_input *self_port,
 299                 struct bt_message_iterator **message_iterator,
 300                 const char *api_func)
 301 {
 302         bt_message_iterator_class_initialize_method init_method = NULL;
 303         struct bt_message_iterator *iterator =
 304                 NULL;
 305         struct bt_message_iterator *downstream_msg_iter =
 306                 (void *) self_downstream_msg_iter;
 307         struct bt_port *port = (void *) self_port;
 308         struct bt_port *upstream_port;
 309         struct bt_component *comp;
 310         struct bt_component *upstream_comp;
 311         struct bt_component_class *upstream_comp_cls;
 312         struct bt_component_class_with_iterator_class *upstream_comp_cls_with_iter_cls;
 313         int status;
 314
 315         BT_ASSERT_PRE_NON_NULL_FROM_FUNC(api_func, "message-iterator-output",
 316                 message_iterator, "Created message iterator (output)");
 317         BT_ASSERT_PRE_NON_NULL_FROM_FUNC(api_func, "input-port", port,
 318                 "Input port");
 319         comp = bt_port_borrow_component_inline(port);
 320         BT_ASSERT_PRE_FROM_FUNC(api_func, "input-port-is-connected",
 321                 bt_port_is_connected(port),
 322                 "Input port is not connected: %![port-]+p", port);
 323         BT_ASSERT_PRE_FROM_FUNC(api_func, "input-port-has-component",
 324                 comp, "Input port is not part of a component: %![port-]+p",
 325                 port);
 326         BT_ASSERT(port->connection);
 327         upstream_port = port->connection->upstream_port;
 328         BT_ASSERT(upstream_port);
 329         upstream_comp = bt_port_borrow_component_inline(upstream_port);
 330         BT_ASSERT(upstream_comp);
 331         BT_ASSERT_PRE_FROM_FUNC(api_func, "graph-is-configured",
 332                 bt_component_borrow_graph(upstream_comp)->config_state ==
 333                         BT_GRAPH_CONFIGURATION_STATE_PARTIALLY_CONFIGURED ||
 334                 bt_component_borrow_graph(upstream_comp)->config_state ==
 335                         BT_GRAPH_CONFIGURATION_STATE_CONFIGURED,
 336                 "Graph is not configured: %!+g",
 337                 bt_component_borrow_graph(upstream_comp));
 338         upstream_comp_cls = upstream_comp->class;
 339         BT_ASSERT(upstream_comp->class->type ==
 340                 BT_COMPONENT_CLASS_TYPE_SOURCE ||
 341                 upstream_comp->class->type ==
 342                 BT_COMPONENT_CLASS_TYPE_FILTER);
 343         BT_LIB_LOGI("Creating message iterator on self component input port: "
 344                 "%![up-comp-]+c, %![up-port-]+p", upstream_comp, upstream_port);
 345         iterator = g_new0(
 346                 struct bt_message_iterator, 1);
 347         if (!iterator) {
 348                 BT_LIB_LOGE_APPEND_CAUSE(
 349                         "Failed to allocate one self component input port "
 350                         "message iterator.");
 351                 status = BT_FUNC_STATUS_MEMORY_ERROR;
 352                 goto error;
 353         }
 354
 355         bt_object_init_shared(&iterator->base,
 356                 bt_message_iterator_destroy);
 357         iterator->msgs = g_ptr_array_new();
 358         if (!iterator->msgs) {
 359                 BT_LIB_LOGE_APPEND_CAUSE("Failed to allocate a GPtrArray.");
 360                 status = BT_FUNC_STATUS_MEMORY_ERROR;
 361                 goto error;
 362         }
 363
 364         g_ptr_array_set_size(iterator->msgs, MSG_BATCH_SIZE);
 365         iterator->last_ns_from_origin = INT64_MIN;
 366
 367 #ifdef BT_DEV_MODE
 368         /* The per-stream state is only used for dev assertions right now. */
 369         iterator->per_stream_state = g_hash_table_new_full(
 370                 g_direct_hash,
 371                 g_direct_equal,
 372                 NULL,
 373                 g_free);
 374 #endif
 375
 376         iterator->auto_seek.msgs = g_queue_new();
 377         if (!iterator->auto_seek.msgs) {
 378                 BT_LIB_LOGE_APPEND_CAUSE("Failed to allocate a GQueue.");
 379                 status = BT_FUNC_STATUS_MEMORY_ERROR;
 380                 goto error;
 381         }
 382
 383         iterator->upstream_msg_iters = g_ptr_array_new();
 384         if (!iterator->upstream_msg_iters) {
 385                 BT_LIB_LOGE_APPEND_CAUSE("Failed to allocate a GPtrArray.");
 386                 status = BT_FUNC_STATUS_MEMORY_ERROR;
 387                 goto error;
 388         }
 389
 390         iterator->upstream_component = upstream_comp;
 391         iterator->upstream_port = upstream_port;
 392         iterator->connection = iterator->upstream_port->connection;
 393         iterator->graph = bt_component_borrow_graph(upstream_comp);
 394         set_msg_iterator_state(iterator,
 395                 BT_MESSAGE_ITERATOR_STATE_NON_INITIALIZED);
 396
 397         /* Copy methods from the message iterator class to the message iterator. */
 398         BT_ASSERT(bt_component_class_has_message_iterator_class(upstream_comp_cls));
 399         upstream_comp_cls_with_iter_cls = container_of(upstream_comp_cls,
 400                 struct bt_component_class_with_iterator_class, parent);
 401
 402         iterator->methods.next =
 403                 (bt_message_iterator_next_method)
 404                         upstream_comp_cls_with_iter_cls->msg_iter_cls->methods.next;
 405         iterator->methods.seek_ns_from_origin =
 406                 (bt_message_iterator_seek_ns_from_origin_method)
 407                         upstream_comp_cls_with_iter_cls->msg_iter_cls->methods.seek_ns_from_origin;
 408         iterator->methods.seek_beginning =
 409                 (bt_message_iterator_seek_beginning_method)
 410                         upstream_comp_cls_with_iter_cls->msg_iter_cls->methods.seek_beginning;
 411         iterator->methods.can_seek_ns_from_origin =
 412                 (bt_message_iterator_can_seek_ns_from_origin_method)
 413                         upstream_comp_cls_with_iter_cls->msg_iter_cls->methods.can_seek_ns_from_origin;
 414         iterator->methods.can_seek_beginning =
 415                 (bt_message_iterator_can_seek_beginning_method)
 416                         upstream_comp_cls_with_iter_cls->msg_iter_cls->methods.can_seek_beginning;
 417
 418         if (iterator->methods.seek_ns_from_origin &&
 419                         !iterator->methods.can_seek_ns_from_origin) {
 420                 iterator->methods.can_seek_ns_from_origin =
 421                         (bt_message_iterator_can_seek_ns_from_origin_method)
 422                                 can_seek_ns_from_origin_true;
 423         }
 424
 425         if (iterator->methods.seek_beginning &&
 426                         !iterator->methods.can_seek_beginning) {
 427                 iterator->methods.can_seek_beginning =
 428                         (bt_message_iterator_can_seek_beginning_method)
 429                                 can_seek_beginning_true;
 430         }
 431
 432         /* Call iterator's init method. */
 433         init_method = upstream_comp_cls_with_iter_cls->msg_iter_cls->methods.initialize;
 434
 435         if (init_method) {
 436                 enum bt_message_iterator_class_initialize_method_status iter_status;
 437
 438                 BT_LIB_LOGD("Calling user's initialization method: %!+i", iterator);
 439                 iter_status = init_method(
 440                         (struct bt_self_message_iterator *) iterator,
 441                         &iterator->config,
 442                         (struct bt_self_component_port_output *) upstream_port);
 443                 BT_LOGD("User method returned: status=%s",
 444                         bt_common_func_status_string(iter_status));
 445                 BT_ASSERT_POST_NO_ERROR_IF_NO_ERROR_STATUS(
 446                         "bt_message_iterator_class_initialize_method",
 447                         iter_status);
 448                 if (iter_status != BT_FUNC_STATUS_OK) {
 449                         BT_LIB_LOGW_APPEND_CAUSE(
 450                                 "Component input port message iterator initialization method failed: "
 451                                 "%![iter-]+i, status=%s",
 452                                 iterator,
 453                                 bt_common_func_status_string(iter_status));
 454                         status = iter_status;
 455                         goto error;
 456                 }
 457
 458                 iterator->config.frozen = true;
 459         }
 460
 461         if (downstream_msg_iter) {
 462                 /* Set this message iterator's downstream message iterator */
 463                 iterator->downstream_msg_iter = downstream_msg_iter;
 464
 465                 /*
 466                  * Add this message iterator to the downstream message
 467                  * iterator's array of upstream message iterators.
 468                  */
 469                 g_ptr_array_add(downstream_msg_iter->upstream_msg_iters,
 470                         iterator);
 471         }
 472
 473         set_msg_iterator_state(iterator,
 474                 BT_MESSAGE_ITERATOR_STATE_ACTIVE);
 475         g_ptr_array_add(port->connection->iterators, iterator);
 476         BT_LIB_LOGI("Created message iterator on self component input port: "
 477                 "%![up-port-]+p, %![up-comp-]+c, %![iter-]+i",
 478                 upstream_port, upstream_comp, iterator);
 479
 480         *message_iterator = iterator;
 481         status = BT_FUNC_STATUS_OK;
 482         goto end;
 483
 484 error:
 485         BT_OBJECT_PUT_REF_AND_RESET(iterator);
 486
 487 end:
 488         return status;
 489 }
 490
 491 BT_EXPORT
 492 bt_message_iterator_create_from_message_iterator_status
 493 bt_message_iterator_create_from_message_iterator(
 494                 struct bt_self_message_iterator *self_msg_iter,
 495                 struct bt_self_component_port_input *input_port,
 496                 struct bt_message_iterator **message_iterator)
 497 {
 498         BT_ASSERT_PRE_NO_ERROR();
 499         BT_ASSERT_PRE_MSG_ITER_NON_NULL(self_msg_iter);
 500         return create_self_component_input_port_message_iterator(self_msg_iter,
 501                 input_port, message_iterator, __func__);
 502 }
 503
 504 BT_EXPORT
 505 bt_message_iterator_create_from_sink_component_status
 506 bt_message_iterator_create_from_sink_component(
 507                 struct bt_self_component_sink *self_comp,
 508                 struct bt_self_component_port_input *input_port,
 509                 struct bt_message_iterator **message_iterator)
 510 {
 511         BT_ASSERT_PRE_NO_ERROR();
 512         BT_ASSERT_PRE_NON_NULL("sink-component", self_comp, "Sink component");
 513         return create_self_component_input_port_message_iterator(NULL,
 514                 input_port, message_iterator, __func__);
 515 }
 516
 517 BT_EXPORT
 518 void *bt_self_message_iterator_get_data(
 519                 const struct bt_self_message_iterator *self_iterator)
 520 {
 521         struct bt_message_iterator *iterator =
 522                 (void *) self_iterator;
 523
 524         BT_ASSERT_PRE_DEV_MSG_ITER_NON_NULL(iterator);
 525         return iterator->user_data;
 526 }
 527
 528 BT_EXPORT
 529 void bt_self_message_iterator_set_data(
 530                 struct bt_self_message_iterator *self_iterator, void *data)
 531 {
 532         struct bt_message_iterator *iterator =
 533                 (void *) self_iterator;
 534
 535         BT_ASSERT_PRE_DEV_MSG_ITER_NON_NULL(iterator);
 536         iterator->user_data = data;
 537         BT_LIB_LOGD("Set message iterator's user data: "
 538                 "%!+i, user-data-addr=%p", iterator, data);
 539 }
 540
 541 BT_EXPORT
 542 void bt_self_message_iterator_configuration_set_can_seek_forward(
 543                 bt_self_message_iterator_configuration *config,
 544                 bt_bool can_seek_forward)
 545 {
 546         BT_ASSERT_PRE_NON_NULL("message-iterator-configuration", config,
 547                 "Message iterator configuration");
 548         BT_ASSERT_PRE_DEV_HOT("message-iterator-configuration", config,
 549                 "Message iterator configuration", "");
 550
 551         config->can_seek_forward = can_seek_forward;
 552 }
 553
 554 /*
 555  * Validate that the default clock snapshot in `msg` doesn't make us go back in
 556  * time.
 557  */
 558
 559 BT_ASSERT_COND_DEV_FUNC
 560 static
 561 bool clock_snapshots_are_monotonic_one(
 562                 struct bt_message_iterator *iterator,
 563                 const bt_message *msg)
 564 {
 565         const struct bt_clock_snapshot *clock_snapshot = NULL;
 566         bt_message_type message_type = bt_message_get_type(msg);
 567         int64_t ns_from_origin;
 568         enum bt_clock_snapshot_get_ns_from_origin_status clock_snapshot_status;
 569
 570         /*
 571          * The default is true: if we can't figure out the clock snapshot
 572          * (or there is none), assume it is fine.
 573          */
 574         bool result = true;
 575
 576         switch (message_type) {
 577         case BT_MESSAGE_TYPE_EVENT:
 578         {
 579                 struct bt_message_event *event_msg = (struct bt_message_event *) msg;
 580                 clock_snapshot = event_msg->default_cs;
 581                 break;
 582         }
 583         case BT_MESSAGE_TYPE_MESSAGE_ITERATOR_INACTIVITY:
 584         {
 585                 struct bt_message_message_iterator_inactivity *inactivity_msg =
 586                         (struct bt_message_message_iterator_inactivity *) msg;
 587                 clock_snapshot = inactivity_msg->cs;
 588                 break;
 589         }
 590         case BT_MESSAGE_TYPE_PACKET_BEGINNING:
 591         case BT_MESSAGE_TYPE_PACKET_END:
 592         {
 593                 struct bt_message_packet *packet_msg = (struct bt_message_packet *) msg;
 594                 clock_snapshot = packet_msg->default_cs;
 595                 break;
 596         }
 597         case BT_MESSAGE_TYPE_STREAM_BEGINNING:
 598         case BT_MESSAGE_TYPE_STREAM_END:
 599         {
 600                 struct bt_message_stream *stream_msg = (struct bt_message_stream *) msg;
 601                 if (stream_msg->default_cs_state != BT_MESSAGE_STREAM_CLOCK_SNAPSHOT_STATE_KNOWN) {
 602                         goto end;
 603                 }
 604
 605                 clock_snapshot = stream_msg->default_cs;
 606                 break;
 607         }
 608         case BT_MESSAGE_TYPE_DISCARDED_EVENTS:
 609         case BT_MESSAGE_TYPE_DISCARDED_PACKETS:
 610         {
 611                 struct bt_message_discarded_items *discarded_msg =
 612                         (struct bt_message_discarded_items *) msg;
 613
 614                 clock_snapshot = discarded_msg->default_begin_cs;
 615                 break;
 616         }
 617         }
 618
 619         if (!clock_snapshot) {
 620                 goto end;
 621         }
 622
 623         clock_snapshot_status = bt_clock_snapshot_get_ns_from_origin(
 624                 clock_snapshot, &ns_from_origin);
 625         if (clock_snapshot_status != BT_FUNC_STATUS_OK) {
 626                 /*
 627                  * bt_clock_snapshot_get_ns_from_origin can return
 628                  * OVERFLOW_ERROR.  We don't really want to report an error to
 629                  * our caller, so just clear it.
 630                  */
 631                 bt_current_thread_clear_error();
 632                 goto end;
 633         }
 634
 635         result = ns_from_origin >= iterator->last_ns_from_origin;
 636         iterator->last_ns_from_origin = ns_from_origin;
 637 end:
 638         return result;
 639 }
 640
 641 BT_ASSERT_COND_DEV_FUNC
 642 static
 643 bool clock_snapshots_are_monotonic(
 644                 struct bt_message_iterator *iterator,
 645                 bt_message_array_const msgs, uint64_t msg_count)
 646 {
 647         uint64_t i;
 648         bool result;
 649
 650         for (i = 0; i < msg_count; i++) {
 651                 if (!clock_snapshots_are_monotonic_one(iterator, msgs[i])) {
 652                         result = false;
 653                         goto end;
 654                 }
 655         }
 656
 657         result = true;
 658
 659 end:
 660         return result;
 661 }
 662
 663 /*
 664  * When a new stream begins, verify that the clock class tied to this
 665  * stream is compatible with what we've seen before.
 666  */
 667
 668 BT_ASSERT_COND_DEV_FUNC
 669 static
 670 bool clock_classes_are_compatible_one(struct bt_message_iterator *iterator,
 671                 const struct bt_message *msg)
 672 {
 673         enum bt_message_type message_type = bt_message_get_type(msg);
 674         bool result;
 675
 676         if (message_type == BT_MESSAGE_TYPE_STREAM_BEGINNING) {
 677                 const struct bt_message_stream *stream_msg = (struct bt_message_stream *) msg;
 678                 const struct bt_clock_class *clock_class = stream_msg->stream->class->default_clock_class;
 679                 bt_uuid clock_class_uuid = NULL;
 680
 681                 if (clock_class) {
 682                         clock_class_uuid = bt_clock_class_get_uuid(clock_class);
 683                 }
 684
 685                 switch (iterator->clock_expectation.type) {
 686                 case CLOCK_EXPECTATION_UNSET:
 687                         /*
 688                          * This is the first time we see a message with a clock
 689                          * snapshot: record the properties of that clock, against
 690                          * which we'll compare the clock properties of the following
 691                          * messages.
 692                          */
 693
 694                         if (!clock_class) {
 695                                 iterator->clock_expectation.type = CLOCK_EXPECTATION_NONE;
 696                         } else if (bt_clock_class_origin_is_unix_epoch(clock_class)) {
 697                                 iterator->clock_expectation.type = CLOCK_EXPECTATION_ORIGIN_UNIX;
 698                         } else if (clock_class_uuid) {
 699                                 iterator->clock_expectation.type = CLOCK_EXPECTATION_ORIGIN_OTHER_UUID;
 700                                 bt_uuid_copy(iterator->clock_expectation.uuid, clock_class_uuid);
 701                         } else {
 702                                 iterator->clock_expectation.type = CLOCK_EXPECTATION_ORIGIN_OTHER_NO_UUID;
 703                         }
 704                         break;
 705
 706                 case CLOCK_EXPECTATION_NONE:
 707                         if (clock_class) {
 708                                 BT_ASSERT_COND_DEV_MSG(
 709                                         "Expecting no clock class, got one: %![cc-]+K",
 710                                         clock_class);
 711                                 result = false;
 712                                 goto end;
 713                         }
 714
 715                         break;
 716
 717                 case CLOCK_EXPECTATION_ORIGIN_UNIX:
 718                         if (!clock_class) {
 719                                 BT_ASSERT_COND_DEV_MSG(
 720                                         "Expecting a clock class, got none.");
 721                                 result = false;
 722                                 goto end;
 723                         }
 724
 725                         if (!bt_clock_class_origin_is_unix_epoch(clock_class)) {
 726                                 BT_ASSERT_COND_DEV_MSG(
 727                                         "Expecting a clock class with Unix epoch origin: %![cc-]+K",
 728                                         clock_class);
 729                                 result = false;
 730                                 goto end;
 731                         }
 732                         break;
 733
 734                 case CLOCK_EXPECTATION_ORIGIN_OTHER_UUID:
 735                         if (!clock_class) {
 736                                 BT_ASSERT_COND_DEV_MSG(
 737                                         "Expecting a clock class, got none.");
 738                                 result = false;
 739                                 goto end;
 740                         }
 741
 742                         if (bt_clock_class_origin_is_unix_epoch(clock_class)) {
 743                                 BT_ASSERT_COND_DEV_MSG(
 744                                         "Expecting a clock class without Unix epoch origin: %![cc-]+K",
 745                                         clock_class);
 746                                 result = false;
 747                                 goto end;
 748                         }
 749
 750                         if (!clock_class_uuid) {
 751                                 BT_ASSERT_COND_DEV_MSG(
 752                                         "Expecting a clock class with UUID: %![cc-]+K",
 753                                         clock_class);
 754                                 result = false;
 755                                 goto end;
 756                         }
 757
 758                         if (bt_uuid_compare(iterator->clock_expectation.uuid, clock_class_uuid)) {
 759                                 BT_ASSERT_COND_DEV_MSG(
 760                                         "Expecting a clock class with UUID, got one "
 761                                         "with a different UUID: %![cc-]+K, expected-uuid=%!u",
 762                                         clock_class, iterator->clock_expectation.uuid);
 763                                 result = false;
 764                                 goto end;
 765                         }
 766                         break;
 767
 768                 case CLOCK_EXPECTATION_ORIGIN_OTHER_NO_UUID:
 769                         if (!clock_class) {
 770                                 BT_ASSERT_COND_DEV_MSG(
 771                                         "Expecting a clock class, got none.");
 772                                 result = false;
 773                                 goto end;
 774                         }
 775
 776                         if (bt_clock_class_origin_is_unix_epoch(clock_class)) {
 777                                 BT_ASSERT_COND_DEV_MSG(
 778                                         "Expecting a clock class without Unix epoch origin: %![cc-]+K",
 779                                         clock_class);
 780                                 result = false;
 781                                 goto end;
 782                         }
 783
 784                         if (clock_class_uuid) {
 785                                 BT_ASSERT_COND_DEV_MSG(
 786                                         "Expecting a clock class without UUID: %![cc-]+K",
 787                                         clock_class);
 788                                 result = false;
 789                                 goto end;
 790                         }
 791                         break;
 792                 }
 793         }
 794
 795         result = true;
 796
 797 end:
 798         return result;
 799 }
 800
 801 BT_ASSERT_COND_DEV_FUNC
 802 static
 803 bool clock_classes_are_compatible(
 804                 struct bt_message_iterator *iterator,
 805                 bt_message_array_const msgs, uint64_t msg_count)
 806 {
 807         uint64_t i;
 808         bool result;
 809
 810         for (i = 0; i < msg_count; i++) {
 811                 if (!clock_classes_are_compatible_one(iterator, msgs[i])) {
 812                         result = false;
 813                         goto end;
 814                 }
 815         }
 816
 817         result = true;
 818
 819 end:
 820         return result;
 821 }
 822
 823 #ifdef BT_DEV_MODE
 824 static
 825 const bt_stream *get_stream_from_msg(const struct bt_message *msg)
 826 {
 827         struct bt_stream *stream;
 828
 829         switch (msg->type) {
 830         case BT_MESSAGE_TYPE_STREAM_BEGINNING:
 831         case BT_MESSAGE_TYPE_STREAM_END:
 832         {
 833                 struct bt_message_stream *msg_stream =
 834                         (struct bt_message_stream *) msg;
 835                 stream = msg_stream->stream;
 836                 break;
 837         }
 838         case BT_MESSAGE_TYPE_EVENT:
 839         {
 840                 struct bt_message_event *msg_event =
 841                         (struct bt_message_event *) msg;
 842                 stream = msg_event->event->stream;
 843                 break;
 844         }
 845         case BT_MESSAGE_TYPE_PACKET_BEGINNING:
 846         case BT_MESSAGE_TYPE_PACKET_END:
 847         {
 848                 struct bt_message_packet *msg_packet =
 849                         (struct bt_message_packet *) msg;
 850                 stream = msg_packet->packet->stream;
 851                 break;
 852         }
 853         case BT_MESSAGE_TYPE_DISCARDED_EVENTS:
 854         case BT_MESSAGE_TYPE_DISCARDED_PACKETS:
 855         {
 856                 struct bt_message_discarded_items *msg_discarded =
 857                         (struct bt_message_discarded_items *) msg;
 858                 stream = msg_discarded->stream;
 859                 break;
 860         }
 861         case BT_MESSAGE_TYPE_MESSAGE_ITERATOR_INACTIVITY:
 862                 stream = NULL;
 863                 break;
 864         default:
 865                 bt_common_abort();
 866         }
 867
 868         return stream;
 869 }
 870
 871 static
 872 GString *message_types_to_string(guint msg_types)
 873 {
 874         GString *str = g_string_new("");
 875
 876         for (int msg_type = 1; msg_type <= BT_MESSAGE_TYPE_MESSAGE_ITERATOR_INACTIVITY;
 877                         msg_type <<= 1) {
 878                 if (msg_type & msg_types) {
 879                         if (str->len > 0) {
 880                                 g_string_append_c(str, '|');
 881                         }
 882
 883                         g_string_append(str,
 884                                 bt_common_message_type_string(msg_type));
 885                 }
 886         }
 887
 888         return str;
 889 }
 890
 891 static
 892 void update_expected_msg_type(const struct bt_stream *stream,
 893                 struct per_stream_state *state,
 894                 const struct bt_message *msg)
 895 {
 896         switch (msg->type) {
 897         case BT_MESSAGE_TYPE_STREAM_BEGINNING:
 898                 state->expected_msg_types = BT_MESSAGE_TYPE_STREAM_END;
 899
 900                 if (stream->class->supports_packets) {
 901                         state->expected_msg_types |=
 902                                 BT_MESSAGE_TYPE_PACKET_BEGINNING;
 903
 904                         if (stream->class->supports_discarded_packets) {
 905                                 state->expected_msg_types |=
 906                                         BT_MESSAGE_TYPE_DISCARDED_PACKETS;
 907                         }
 908                 } else {
 909                         state->expected_msg_types |= BT_MESSAGE_TYPE_EVENT;
 910                 }
 911
 912                 if (stream->class->supports_discarded_events) {
 913                         state->expected_msg_types |=
 914                                 BT_MESSAGE_TYPE_DISCARDED_EVENTS;
 915                 }
 916
 917                 break;
 918         case BT_MESSAGE_TYPE_STREAM_END:
 919                 state->expected_msg_types = 0;
 920                 break;
 921         case BT_MESSAGE_TYPE_EVENT:
 922         {
 923                 state->expected_msg_types = BT_MESSAGE_TYPE_EVENT;
 924
 925                 if (stream->class->supports_packets) {
 926                         state->expected_msg_types |= BT_MESSAGE_TYPE_PACKET_END;
 927                 } else {
 928                         state->expected_msg_types |= BT_MESSAGE_TYPE_STREAM_END;
 929                 }
 930
 931                 if (stream->class->supports_discarded_events) {
 932                         state->expected_msg_types |=
 933                                 BT_MESSAGE_TYPE_DISCARDED_EVENTS;
 934                 }
 935
 936                 break;
 937         }
 938         case BT_MESSAGE_TYPE_PACKET_BEGINNING:
 939         {
 940                 state->expected_msg_types = BT_MESSAGE_TYPE_EVENT |
 941                         BT_MESSAGE_TYPE_PACKET_END;
 942
 943                 if (stream->class->supports_discarded_events) {
 944                         state->expected_msg_types |=
 945                                 BT_MESSAGE_TYPE_DISCARDED_EVENTS;
 946                 }
 947
 948                 break;
 949         }
 950         case BT_MESSAGE_TYPE_PACKET_END:
 951         {
 952                 state->expected_msg_types = BT_MESSAGE_TYPE_PACKET_BEGINNING |
 953                         BT_MESSAGE_TYPE_STREAM_END;
 954
 955                 if (stream->class->supports_discarded_events) {
 956                         state->expected_msg_types |=
 957                                 BT_MESSAGE_TYPE_DISCARDED_EVENTS;
 958                 }
 959
 960                 if (stream->class->supports_discarded_packets) {
 961                         state->expected_msg_types |=
 962                                 BT_MESSAGE_TYPE_DISCARDED_PACKETS;
 963                 }
 964
 965                 break;
 966         }
 967         case BT_MESSAGE_TYPE_DISCARDED_EVENTS:
 968                 state->expected_msg_types = BT_MESSAGE_TYPE_DISCARDED_EVENTS;
 969
 970                 if (state->cur_packet) {
 971                         state->expected_msg_types |= BT_MESSAGE_TYPE_EVENT |
 972                                 BT_MESSAGE_TYPE_PACKET_END;
 973                 } else {
 974                         state->expected_msg_types |= BT_MESSAGE_TYPE_STREAM_END;
 975
 976                         if (stream->class->supports_packets) {
 977                                 state->expected_msg_types |=
 978                                         BT_MESSAGE_TYPE_PACKET_BEGINNING;
 979
 980                                 if (stream->class->supports_discarded_packets) {
 981                                         state->expected_msg_types |=
 982                                                 BT_MESSAGE_TYPE_DISCARDED_PACKETS;
 983                                 }
 984                         } else {
 985                                 state->expected_msg_types |=
 986                                         BT_MESSAGE_TYPE_EVENT;
 987                         }
 988                 }
 989
 990                 break;
 991         case BT_MESSAGE_TYPE_DISCARDED_PACKETS:
 992                 state->expected_msg_types = BT_MESSAGE_TYPE_DISCARDED_PACKETS |
 993                         BT_MESSAGE_TYPE_PACKET_BEGINNING |
 994                         BT_MESSAGE_TYPE_STREAM_END;
 995
 996                 if (stream->class->supports_discarded_events) {
 997                         state->expected_msg_types |=
 998                                 BT_MESSAGE_TYPE_DISCARDED_EVENTS;
 999                 }
1000                 break;
1001         default:
1002                 /*
1003                  * Other message types are not associated to a stream, so we
1004                  * should not get them here.
1005                  */
1006                 bt_common_abort();
1007         }
1008 }
1009
1010 static
1011 struct per_stream_state *get_per_stream_state(
1012                 struct bt_message_iterator *iterator,
1013                 const struct bt_stream *stream)
1014 {
1015         struct per_stream_state *state = g_hash_table_lookup(
1016                 iterator->per_stream_state, stream);
1017
1018         if (!state) {
1019                 state = g_new0(struct per_stream_state, 1);
1020                 state->expected_msg_types = BT_MESSAGE_TYPE_STREAM_BEGINNING;
1021                 g_hash_table_insert(iterator->per_stream_state,
1022                         (gpointer) stream, state);
1023         }
1024
1025         return state;
1026 }
1027 #endif
1028
1029 #define NEXT_METHOD_NAME        "bt_message_iterator_class_next_method"
1030
1031 #ifdef BT_DEV_MODE
1032 static
1033 void assert_post_dev_expected_sequence(struct bt_message_iterator *iterator,
1034                 const struct bt_message *msg)
1035 {
1036         const bt_stream *stream = get_stream_from_msg(msg);
1037         struct per_stream_state *state;
1038
1039         if (!stream) {
1040                 goto end;
1041         }
1042
1043         state = get_per_stream_state(iterator, stream);
1044
1045         /*
1046          * We don't free the return value of message_types_to_string(), but
1047          * that's because we know the program is going to abort anyway, and
1048          * we don't want to call it if the assertion holds.
1049          */
1050         BT_ASSERT_POST_DEV(NEXT_METHOD_NAME,
1051                 "message-type-is-expected",
1052                 msg->type & state->expected_msg_types,
1053                 "Unexpected message type: %![stream-]s, %![iterator-]i, "
1054                 "%![message-]n, expected-msg-types=%s",
1055                 stream, iterator, msg,
1056                 message_types_to_string(state->expected_msg_types)->str);
1057
1058         update_expected_msg_type(stream, state, msg);
1059
1060 end:
1061         return;
1062 }
1063
1064 static
1065 void assert_post_dev_expected_packet(struct bt_message_iterator *iterator,
1066                 const struct bt_message *msg)
1067 {
1068         const bt_stream *stream = get_stream_from_msg(msg);
1069         struct per_stream_state *state;
1070         const bt_packet *actual_packet = NULL;
1071         const bt_packet *expected_packet = NULL;
1072
1073         if (!stream) {
1074                 goto end;
1075         }
1076
1077         state = get_per_stream_state(iterator, stream);
1078
1079         switch (msg->type) {
1080         case BT_MESSAGE_TYPE_EVENT:
1081         {
1082                 const struct bt_message_event *msg_event =
1083                         (const struct bt_message_event *) msg;
1084
1085                 actual_packet = msg_event->event->packet;
1086                 expected_packet = state->cur_packet;
1087                 break;
1088         }
1089         case BT_MESSAGE_TYPE_PACKET_BEGINNING:
1090         {
1091                 const struct bt_message_packet *msg_packet =
1092                         (const struct bt_message_packet *) msg;
1093
1094                 BT_ASSERT(!state->cur_packet);
1095                 state->cur_packet = msg_packet->packet;
1096                 break;
1097         }
1098         case BT_MESSAGE_TYPE_PACKET_END:
1099         {
1100                 const struct bt_message_packet *msg_packet =
1101                         (const struct bt_message_packet *) msg;
1102
1103                 actual_packet = msg_packet->packet;
1104                 expected_packet = state->cur_packet;
1105                 BT_ASSERT(state->cur_packet);
1106                 state->cur_packet = NULL;
1107                 break;
1108         }
1109         default:
1110                 break;
1111         }
1112
1113         BT_ASSERT_POST_DEV(NEXT_METHOD_NAME,
1114                 "message-packet-is-expected",
1115                 actual_packet == expected_packet,
1116                 "Message's packet is not expected: %![stream-]s, %![iterator-]i, "
1117                 "%![message-]n, %![received-packet-]a, %![expected-packet-]a",
1118                 stream, iterator, msg, actual_packet, expected_packet);
1119
1120 end:
1121         return;
1122 }
1123
1124 static
1125 void assert_post_dev_next(
1126                 struct bt_message_iterator *iterator,
1127                 bt_message_iterator_class_next_method_status status,
1128                 bt_message_array_const msgs, uint64_t msg_count)
1129 {
1130         if (status == BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_OK) {
1131                 uint64_t i;
1132
1133                 for (i = 0; i < msg_count; i++) {
1134                         assert_post_dev_expected_sequence(iterator, msgs[i]);
1135                         assert_post_dev_expected_packet(iterator, msgs[i]);
1136                 }
1137         } else if (status == BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_END) {
1138                 GHashTableIter iter;
1139
1140                 gpointer stream_v, stream_state_v;
1141
1142                 g_hash_table_iter_init(&iter, iterator->per_stream_state);
1143                 while (g_hash_table_iter_next(&iter, &stream_v,
1144                                 &stream_state_v)) {
1145                         struct bt_stream *stream = stream_v;
1146                         struct per_stream_state *stream_state = stream_state_v;
1147
1148                         BT_ASSERT_POST_DEV(NEXT_METHOD_NAME,
1149                                 "stream-is-ended",
1150                                 stream_state->expected_msg_types == 0,
1151                                 "Stream is not ended: %![stream-]s, "
1152                                 "%![iterator-]i, expected-msg-types=%s",
1153                                 stream, iterator,
1154                                 message_types_to_string(
1155                                         stream_state->expected_msg_types)->str);
1156                 }
1157
1158         }
1159 }
1160 #endif
1161
1162 /*
1163  * Call the `next` method of the iterator.  Do some validation on the returned
1164  * messages.
1165  */
1166
1167 static
1168 enum bt_message_iterator_class_next_method_status
1169 call_iterator_next_method(
1170                 struct bt_message_iterator *iterator,
1171                 bt_message_array_const msgs, uint64_t capacity, uint64_t *user_count)
1172 {
1173         enum bt_message_iterator_class_next_method_status status;
1174
1175         BT_ASSERT_DBG(iterator->methods.next);
1176         BT_LOGD_STR("Calling user's \"next\" method.");
1177         status = iterator->methods.next(iterator, msgs, capacity, user_count);
1178         BT_LOGD("User method returned: status=%s, msg-count=%" PRIu64,
1179                 bt_common_func_status_string(status), *user_count);
1180
1181         if (status == BT_FUNC_STATUS_OK) {
1182                 BT_ASSERT_POST_DEV(NEXT_METHOD_NAME,
1183                         "message-clock-classes-are-compatible",
1184                         clock_classes_are_compatible(iterator, msgs,
1185                                 *user_count),
1186                         "Clocks are not compatible");
1187                 BT_ASSERT_POST_DEV(NEXT_METHOD_NAME,
1188                         "message-clock-snapshots-are-monotonic",
1189                         clock_snapshots_are_monotonic(iterator, msgs,
1190                                 *user_count),
1191                         "Clock snapshots are not monotonic");
1192         }
1193
1194 #ifdef BT_DEV_MODE
1195         assert_post_dev_next(iterator, status, msgs, *user_count);
1196 #endif
1197
1198         BT_ASSERT_POST_DEV_NO_ERROR_IF_NO_ERROR_STATUS(NEXT_METHOD_NAME,
1199                 status);
1200
1201         return status;
1202 }
1203
1204 BT_EXPORT
1205 enum bt_message_iterator_next_status
1206 bt_message_iterator_next(
1207                 struct bt_message_iterator *iterator,
1208                 bt_message_array_const *msgs, uint64_t *user_count)
1209 {
1210         enum bt_message_iterator_next_status status = BT_FUNC_STATUS_OK;
1211
1212         BT_ASSERT_PRE_DEV_NO_ERROR();
1213         BT_ASSERT_PRE_DEV_MSG_ITER_NON_NULL(iterator);
1214         BT_ASSERT_PRE_DEV_NON_NULL("message-array-output", msgs,
1215                 "Message array (output)");
1216         BT_ASSERT_PRE_DEV_NON_NULL("user-count-output", user_count,
1217                 "Message count (output)");
1218         BT_ASSERT_PRE_DEV("message-iterator-is-active",
1219                 iterator->state == BT_MESSAGE_ITERATOR_STATE_ACTIVE,
1220                 "Message iterator's \"next\" called, but "
1221                 "message iterator is in the wrong state: %!+i", iterator);
1222         BT_ASSERT_DBG(iterator->upstream_component);
1223         BT_ASSERT_DBG(iterator->upstream_component->class);
1224         BT_ASSERT_PRE_DEV("graph-is-configured",
1225                 bt_component_borrow_graph(iterator->upstream_component)->config_state !=
1226                         BT_GRAPH_CONFIGURATION_STATE_CONFIGURING,
1227                 "Graph is not configured: %!+g",
1228                 bt_component_borrow_graph(iterator->upstream_component));
1229         BT_LIB_LOGD("Getting next self component input port "
1230                 "message iterator's messages: %!+i, batch-size=%u",
1231                 iterator, MSG_BATCH_SIZE);
1232
1233         /*
1234          * Call the user's "next" method to get the next messages
1235          * and status.
1236          */
1237         *user_count = 0;
1238         status = (int) call_iterator_next_method(iterator,
1239                 (void *) iterator->msgs->pdata, MSG_BATCH_SIZE,
1240                 user_count);
1241         BT_LOGD("User method returned: status=%s, msg-count=%" PRIu64,
1242                 bt_common_func_status_string(status), *user_count);
1243         if (status < 0) {
1244                 BT_LIB_LOGW_APPEND_CAUSE(
1245                         "Component input port message iterator's \"next\" method failed: "
1246                         "%![iter-]+i, status=%s",
1247                         iterator, bt_common_func_status_string(status));
1248                 goto end;
1249         }
1250
1251         /*
1252          * There is no way that this iterator could have been finalized
1253          * during its "next" method, as the only way to do this is to
1254          * put the last iterator's reference, and this can only be done
1255          * by its downstream owner.
1256          *
1257          * For the same reason, there is no way that this iterator could
1258          * have sought (cannot seek a self message iterator).
1259          */
1260         BT_ASSERT_DBG(iterator->state ==
1261                 BT_MESSAGE_ITERATOR_STATE_ACTIVE);
1262
1263         switch (status) {
1264         case BT_FUNC_STATUS_OK:
1265                 BT_ASSERT_POST_DEV(NEXT_METHOD_NAME, "count-lteq-capacity",
1266                         *user_count <= MSG_BATCH_SIZE,
1267                         "Invalid returned message count: greater than "
1268                         "batch size: count=%" PRIu64 ", batch-size=%u",
1269                         *user_count, MSG_BATCH_SIZE);
1270                 *msgs = (void *) iterator->msgs->pdata;
1271                 break;
1272         case BT_FUNC_STATUS_AGAIN:
1273                 goto end;
1274         case BT_FUNC_STATUS_END:
1275                 set_msg_iterator_state(iterator,
1276                         BT_MESSAGE_ITERATOR_STATE_ENDED);
1277                 goto end;
1278         default:
1279                 /* Unknown non-error status */
1280                 bt_common_abort();
1281         }
1282
1283 end:
1284         return status;
1285 }
1286
1287 BT_EXPORT
1288 struct bt_component *
1289 bt_message_iterator_borrow_component(
1290                 struct bt_message_iterator *iterator)
1291 {
1292         BT_ASSERT_PRE_DEV_MSG_ITER_NON_NULL(iterator);
1293         return iterator->upstream_component;
1294 }
1295
1296 BT_EXPORT
1297 struct bt_self_component *bt_self_message_iterator_borrow_component(
1298                 struct bt_self_message_iterator *self_iterator)
1299 {
1300         struct bt_message_iterator *iterator =
1301                 (void *) self_iterator;
1302
1303         BT_ASSERT_PRE_DEV_MSG_ITER_NON_NULL(iterator);
1304         return (void *) iterator->upstream_component;
1305 }
1306
1307 BT_EXPORT
1308 struct bt_self_component_port_output *bt_self_message_iterator_borrow_port(
1309                 struct bt_self_message_iterator *self_iterator)
1310 {
1311         struct bt_message_iterator *iterator =
1312                 (void *) self_iterator;
1313
1314         BT_ASSERT_PRE_DEV_MSG_ITER_NON_NULL(iterator);
1315         return (void *) iterator->upstream_port;
1316 }
1317
1318 #define CAN_SEEK_NS_FROM_ORIGIN_METHOD_NAME                             \
1319         "bt_message_iterator_class_can_seek_ns_from_origin_method"
1320
1321 BT_EXPORT
1322 enum bt_message_iterator_can_seek_ns_from_origin_status
1323 bt_message_iterator_can_seek_ns_from_origin(
1324                 struct bt_message_iterator *iterator,
1325                 int64_t ns_from_origin, bt_bool *can_seek)
1326 {
1327         enum bt_message_iterator_can_seek_ns_from_origin_status status;
1328
1329         BT_ASSERT_PRE_NO_ERROR();
1330         BT_ASSERT_PRE_MSG_ITER_NON_NULL(iterator);
1331         BT_ASSERT_PRE_RES_OUT_NON_NULL(can_seek);
1332         BT_ASSERT_PRE_ITER_HAS_STATE_TO_SEEK(iterator);
1333         BT_ASSERT_PRE("graph-is-configured",
1334                 bt_component_borrow_graph(iterator->upstream_component)->config_state !=
1335                         BT_GRAPH_CONFIGURATION_STATE_CONFIGURING,
1336                 "Graph is not configured: %!+g",
1337                 bt_component_borrow_graph(iterator->upstream_component));
1338
1339         if (iterator->methods.can_seek_ns_from_origin) {
1340                 /*
1341                  * Initialize to an invalid value, so we can post-assert that
1342                  * the method returned a valid value.
1343                  */
1344                 *can_seek = -1;
1345
1346                 BT_LIB_LOGD("Calling user's \"can seek nanoseconds from origin\" method: %!+i",
1347                         iterator);
1348
1349                 status = (int) iterator->methods.can_seek_ns_from_origin(iterator,
1350                         ns_from_origin, can_seek);
1351
1352                 BT_ASSERT_POST_NO_ERROR_IF_NO_ERROR_STATUS(
1353                         CAN_SEEK_NS_FROM_ORIGIN_METHOD_NAME, status);
1354
1355                 if (status != BT_FUNC_STATUS_OK) {
1356                         BT_LIB_LOGW_APPEND_CAUSE(
1357                                 "Component input port message iterator's \"can seek nanoseconds from origin\" method failed: "
1358                                 "%![iter-]+i, status=%s",
1359                                 iterator, bt_common_func_status_string(status));
1360                         goto end;
1361                 }
1362
1363                 BT_ASSERT_POST(CAN_SEEK_NS_FROM_ORIGIN_METHOD_NAME,
1364                         "valid-return-value",
1365                         *can_seek == BT_TRUE || *can_seek == BT_FALSE,
1366                         "Unexpected boolean value returned from user's \"can seek ns from origin\" method: val=%d, %![iter-]+i",
1367                         *can_seek, iterator);
1368
1369                 BT_LIB_LOGD(
1370                         "User's \"can seek nanoseconds from origin\" returned successfully: "
1371                         "%![iter-]+i, can-seek=%d",
1372                         iterator, *can_seek);
1373
1374                 if (*can_seek) {
1375                         goto end;
1376                 }
1377         }
1378
1379         /*
1380          * Automatic seeking fall back: if we can seek to the beginning and the
1381          * iterator supports forward seeking then we can automatically seek to
1382          * any timestamp.
1383          */
1384         status = (int) bt_message_iterator_can_seek_beginning(
1385                 iterator, can_seek);
1386         if (status != BT_FUNC_STATUS_OK) {
1387                 goto end;
1388         }
1389
1390         *can_seek = *can_seek && iterator->config.can_seek_forward;
1391
1392 end:
1393         return status;
1394 }
1395
1396 #define CAN_SEEK_BEGINNING_METHOD_NAME                                  \
1397         "bt_message_iterator_class_can_seek_beginning"
1398
1399 BT_EXPORT
1400 enum bt_message_iterator_can_seek_beginning_status
1401 bt_message_iterator_can_seek_beginning(
1402                 struct bt_message_iterator *iterator,
1403                 bt_bool *can_seek)
1404 {
1405         enum bt_message_iterator_can_seek_beginning_status status;
1406
1407         BT_ASSERT_PRE_NO_ERROR();
1408         BT_ASSERT_PRE_MSG_ITER_NON_NULL(iterator);
1409         BT_ASSERT_PRE_RES_OUT_NON_NULL(can_seek);
1410         BT_ASSERT_PRE_ITER_HAS_STATE_TO_SEEK(iterator);
1411         BT_ASSERT_PRE("graph-is-configured",
1412                 bt_component_borrow_graph(iterator->upstream_component)->config_state !=
1413                         BT_GRAPH_CONFIGURATION_STATE_CONFIGURING,
1414                 "Graph is not configured: %!+g",
1415                 bt_component_borrow_graph(iterator->upstream_component));
1416
1417         if (iterator->methods.can_seek_beginning) {
1418                 /*
1419                  * Initialize to an invalid value, so we can post-assert that
1420                  * the method returned a valid value.
1421                  */
1422                 *can_seek = -1;
1423
1424                 status = (int) iterator->methods.can_seek_beginning(iterator, can_seek);
1425
1426                 BT_ASSERT_POST(CAN_SEEK_BEGINNING_METHOD_NAME,
1427                         "valid-return-value",
1428                         status != BT_FUNC_STATUS_OK ||
1429                                 *can_seek == BT_TRUE ||
1430                                 *can_seek == BT_FALSE,
1431                         "Unexpected boolean value returned from user's \"can seek beginning\" method: val=%d, %![iter-]+i",
1432                         *can_seek, iterator);
1433                 BT_ASSERT_POST_NO_ERROR_IF_NO_ERROR_STATUS(
1434                         CAN_SEEK_BEGINNING_METHOD_NAME, status);
1435         } else {
1436                 *can_seek = BT_FALSE;
1437                 status = BT_FUNC_STATUS_OK;
1438         }
1439
1440         return status;
1441 }
1442
1443 static inline
1444 void set_iterator_state_after_seeking(
1445                 struct bt_message_iterator *iterator,
1446                 int status)
1447 {
1448         enum bt_message_iterator_state new_state = 0;
1449
1450         /* Set iterator's state depending on seeking status */
1451         switch (status) {
1452         case BT_FUNC_STATUS_OK:
1453                 new_state = BT_MESSAGE_ITERATOR_STATE_ACTIVE;
1454                 break;
1455         case BT_FUNC_STATUS_AGAIN:
1456                 new_state = BT_MESSAGE_ITERATOR_STATE_LAST_SEEKING_RETURNED_AGAIN;
1457                 break;
1458         case BT_FUNC_STATUS_ERROR:
1459         case BT_FUNC_STATUS_MEMORY_ERROR:
1460                 new_state = BT_MESSAGE_ITERATOR_STATE_LAST_SEEKING_RETURNED_ERROR;
1461                 break;
1462         case BT_FUNC_STATUS_END:
1463                 new_state = BT_MESSAGE_ITERATOR_STATE_ENDED;
1464                 break;
1465         default:
1466                 bt_common_abort();
1467         }
1468
1469         set_msg_iterator_state(iterator, new_state);
1470 }
1471
1472 static
1473 void reset_iterator_expectations(
1474                 struct bt_message_iterator *iterator)
1475 {
1476         iterator->last_ns_from_origin = INT64_MIN;
1477         iterator->clock_expectation.type = CLOCK_EXPECTATION_UNSET;
1478 }
1479
1480 static
1481 bool message_iterator_can_seek_beginning(
1482                 struct bt_message_iterator *iterator)
1483 {
1484         enum bt_message_iterator_can_seek_beginning_status status;
1485         bt_bool can_seek;
1486
1487         status = bt_message_iterator_can_seek_beginning(
1488                 iterator, &can_seek);
1489         if (status != BT_FUNC_STATUS_OK) {
1490                 can_seek = BT_FALSE;
1491         }
1492
1493         return can_seek;
1494 }
1495
1496 #define SEEK_BEGINNING_METHOD_NAME                                      \
1497         "bt_message_iterator_class_seek_beginning_method"
1498
1499 BT_EXPORT
1500 enum bt_message_iterator_seek_beginning_status
1501 bt_message_iterator_seek_beginning(struct bt_message_iterator *iterator)
1502 {
1503         int status;
1504
1505         BT_ASSERT_PRE_NO_ERROR();
1506         BT_ASSERT_PRE_MSG_ITER_NON_NULL(iterator);
1507         BT_ASSERT_PRE_ITER_HAS_STATE_TO_SEEK(iterator);
1508         BT_ASSERT_PRE("graph-is-configured",
1509                 bt_component_borrow_graph(iterator->upstream_component)->config_state !=
1510                         BT_GRAPH_CONFIGURATION_STATE_CONFIGURING,
1511                 "Graph is not configured: %!+g",
1512                 bt_component_borrow_graph(iterator->upstream_component));
1513         BT_ASSERT_PRE("can-seek-beginning",
1514                 message_iterator_can_seek_beginning(iterator),
1515                 "Message iterator cannot seek beginning: %!+i", iterator);
1516
1517         /*
1518          * We are seeking, reset our expectations about how the following
1519          * messages should look like.
1520          */
1521         reset_iterator_expectations(iterator);
1522
1523         BT_LIB_LOGD("Calling user's \"seek beginning\" method: %!+i", iterator);
1524         set_msg_iterator_state(iterator,
1525                 BT_MESSAGE_ITERATOR_STATE_SEEKING);
1526         status = iterator->methods.seek_beginning(iterator);
1527         BT_LOGD("User method returned: status=%s",
1528                 bt_common_func_status_string(status));
1529         BT_ASSERT_POST(SEEK_BEGINNING_METHOD_NAME, "valid-status",
1530                 status == BT_FUNC_STATUS_OK ||
1531                 status == BT_FUNC_STATUS_ERROR ||
1532                 status == BT_FUNC_STATUS_MEMORY_ERROR ||
1533                 status == BT_FUNC_STATUS_AGAIN,
1534                 "Unexpected status: %![iter-]+i, status=%s",
1535                 iterator, bt_common_func_status_string(status));
1536         BT_ASSERT_POST_NO_ERROR_IF_NO_ERROR_STATUS(SEEK_BEGINNING_METHOD_NAME,
1537                 status);
1538         if (status < 0) {
1539                 BT_LIB_LOGW_APPEND_CAUSE(
1540                         "Component input port message iterator's \"seek beginning\" method failed: "
1541                         "%![iter-]+i, status=%s",
1542                         iterator, bt_common_func_status_string(status));
1543         }
1544
1545         clear_per_stream_state(iterator);
1546
1547         set_iterator_state_after_seeking(iterator, status);
1548         return status;
1549 }
1550
1551 BT_EXPORT
1552 bt_bool
1553 bt_message_iterator_can_seek_forward(
1554                 bt_message_iterator *iterator)
1555 {
1556         BT_ASSERT_PRE_MSG_ITER_NON_NULL(iterator);
1557
1558         return iterator->config.can_seek_forward;
1559 }
1560
1561 /*
1562  * Structure used to record the state of a given stream during the fast-forward
1563  * phase of an auto-seek.
1564  */
1565 struct auto_seek_stream_state {
1566         /*
1567          * Value representing which step of this timeline we are at.
1568          *
1569          *      time --->
1570          *   [SB]  1  [PB]  2  [PE]  1  [SE]
1571          *
1572          * At each point in the timeline, the messages we need to replicate are:
1573          *
1574          *   1: Stream beginning
1575          *   2: Stream beginning, packet beginning
1576          *
1577          * Before "Stream beginning" and after "Stream end", we don't need to
1578          * replicate anything as the stream doesn't exist.
1579          */
1580         enum {
1581                 AUTO_SEEK_STREAM_STATE_STREAM_BEGAN,
1582                 AUTO_SEEK_STREAM_STATE_PACKET_BEGAN,
1583         } state;
1584
1585         /*
1586          * If `state` is AUTO_SEEK_STREAM_STATE_PACKET_BEGAN, the packet we are
1587          * in.  This is a weak reference, since the packet will always be
1588          * alive by the time we use it.
1589          */
1590         struct bt_packet *packet;
1591
1592         /* Have we see a message with a clock snapshot yet? */
1593         bool seen_clock_snapshot;
1594 };
1595
1596 static
1597 struct auto_seek_stream_state *create_auto_seek_stream_state(void)
1598 {
1599         return g_new0(struct auto_seek_stream_state, 1);
1600 }
1601
1602 static
1603 void destroy_auto_seek_stream_state(void *ptr)
1604 {
1605         g_free(ptr);
1606 }
1607
1608 static
1609 GHashTable *create_auto_seek_stream_states(void)
1610 {
1611         return g_hash_table_new_full(g_direct_hash, g_direct_equal, NULL,
1612                 destroy_auto_seek_stream_state);
1613 }
1614
1615 static
1616 void destroy_auto_seek_stream_states(GHashTable *stream_states)
1617 {
1618         g_hash_table_destroy(stream_states);
1619 }
1620
1621 /*
1622  * Handle one message while we are in the fast-forward phase of an auto-seek.
1623  *
1624  * Sets `*got_first` to true if the message's timestamp is greater or equal to
1625  * `ns_from_origin`.  In other words, if this is the first message after our
1626  * seek point.
1627  *
1628  * `stream_states` is an hash table of `bt_stream *` (weak reference) to
1629  * `struct auto_seek_stream_state` used to keep the state of each stream
1630  * during the fast-forward.
1631  */
1632
1633 static inline
1634 int auto_seek_handle_message(
1635                 struct bt_message_iterator *iterator,
1636                 int64_t ns_from_origin, const struct bt_message *msg,
1637                 bool *got_first, GHashTable *stream_states)
1638 {
1639         int status = BT_FUNC_STATUS_OK;
1640         int64_t msg_ns_from_origin;
1641         const struct bt_clock_snapshot *clk_snapshot = NULL;
1642         int ret;
1643
1644         BT_ASSERT_DBG(msg);
1645         BT_ASSERT_DBG(got_first);
1646
1647         switch (msg->type) {
1648         case BT_MESSAGE_TYPE_EVENT:
1649         {
1650                 const struct bt_message_event *event_msg =
1651                         (const void *) msg;
1652
1653                 clk_snapshot = event_msg->default_cs;
1654                 BT_ASSERT_POST_DEV(NEXT_METHOD_NAME,
1655                         "event-message-has-default-clock-snapshot",
1656                         clk_snapshot,
1657                         "Event message has no default clock snapshot: %!+n",
1658                         event_msg);
1659                 break;
1660         }
1661         case BT_MESSAGE_TYPE_MESSAGE_ITERATOR_INACTIVITY:
1662         {
1663                 const struct bt_message_message_iterator_inactivity *inactivity_msg =
1664                         (const void *) msg;
1665
1666                 clk_snapshot = inactivity_msg->cs;
1667                 BT_ASSERT_DBG(clk_snapshot);
1668                 break;
1669         }
1670         case BT_MESSAGE_TYPE_PACKET_BEGINNING:
1671         case BT_MESSAGE_TYPE_PACKET_END:
1672         {
1673                 const struct bt_message_packet *packet_msg =
1674                         (const void *) msg;
1675
1676                 if (msg->type == BT_MESSAGE_TYPE_PACKET_BEGINNING
1677                                 && !packet_msg->packet->stream->class->packets_have_beginning_default_clock_snapshot) {
1678                         goto skip_msg;
1679                 }
1680
1681                 if (msg->type == BT_MESSAGE_TYPE_PACKET_END
1682                                 && !packet_msg->packet->stream->class->packets_have_end_default_clock_snapshot) {
1683                         goto skip_msg;
1684                 }
1685
1686                 clk_snapshot = packet_msg->default_cs;
1687                 BT_ASSERT_POST_DEV(NEXT_METHOD_NAME,
1688                         "packet-message-has-default-clock-snapshot",
1689                         clk_snapshot,
1690                         "Packet message has no default clock snapshot: %!+n",
1691                         packet_msg);
1692                 break;
1693         }
1694         case BT_MESSAGE_TYPE_DISCARDED_EVENTS:
1695         case BT_MESSAGE_TYPE_DISCARDED_PACKETS:
1696         {
1697                 struct bt_message_discarded_items *msg_disc_items =
1698                         (void *) msg;
1699
1700                 if (msg->type == BT_MESSAGE_TYPE_DISCARDED_EVENTS &&
1701                                 !msg_disc_items->stream->class->discarded_events_have_default_clock_snapshots) {
1702                         goto skip_msg;
1703                 }
1704
1705                 if (msg->type == BT_MESSAGE_TYPE_DISCARDED_PACKETS &&
1706                                 !msg_disc_items->stream->class->discarded_packets_have_default_clock_snapshots) {
1707                         goto skip_msg;
1708                 }
1709
1710                 BT_ASSERT_POST_DEV(NEXT_METHOD_NAME,
1711                         "discarded-events-packets-message-has-default-clock-snapshot",
1712                         msg_disc_items->default_begin_cs &&
1713                                 msg_disc_items->default_end_cs,
1714                         "Discarded events/packets message has no default clock snapshots: %!+n",
1715                         msg_disc_items);
1716                 ret = bt_clock_snapshot_get_ns_from_origin(
1717                         msg_disc_items->default_begin_cs,
1718                         &msg_ns_from_origin);
1719                 if (ret) {
1720                         status = BT_FUNC_STATUS_ERROR;
1721                         goto end;
1722                 }
1723
1724                 if (msg_ns_from_origin >= ns_from_origin) {
1725                         *got_first = true;
1726                         goto push_msg;
1727                 }
1728
1729                 ret = bt_clock_snapshot_get_ns_from_origin(
1730                         msg_disc_items->default_end_cs,
1731                         &msg_ns_from_origin);
1732                 if (ret) {
1733                         status = BT_FUNC_STATUS_ERROR;
1734                         goto end;
1735                 }
1736
1737                 if (msg_ns_from_origin >= ns_from_origin) {
1738                         /*
1739                          * The discarded items message's beginning time
1740                          * is before the requested seeking time, but its
1741                          * end time is after. Modify the message so as
1742                          * to set its beginning time to the requested
1743                          * seeking time, and make its item count unknown
1744                          * as we don't know if items were really
1745                          * discarded within the new time range.
1746                          */
1747                         uint64_t new_begin_raw_value = 0;
1748
1749                         ret = bt_clock_class_clock_value_from_ns_from_origin(
1750                                 msg_disc_items->default_end_cs->clock_class,
1751                                 ns_from_origin, &new_begin_raw_value);
1752                         if (ret) {
1753                                 status = BT_FUNC_STATUS_ERROR;
1754                                 goto end;
1755                         }
1756
1757                         bt_clock_snapshot_set_raw_value(
1758                                 msg_disc_items->default_begin_cs,
1759                                 new_begin_raw_value);
1760                         msg_disc_items->count.base.avail =
1761                                 BT_PROPERTY_AVAILABILITY_NOT_AVAILABLE;
1762
1763                         /*
1764                          * It is safe to push it because its beginning
1765                          * time is exactly the requested seeking time.
1766                          */
1767                         goto push_msg;
1768                 } else {
1769                         goto skip_msg;
1770                 }
1771         }
1772         case BT_MESSAGE_TYPE_STREAM_BEGINNING:
1773         case BT_MESSAGE_TYPE_STREAM_END:
1774         {
1775                 struct bt_message_stream *stream_msg =
1776                         (struct bt_message_stream *) msg;
1777
1778                 if (stream_msg->default_cs_state != BT_MESSAGE_STREAM_CLOCK_SNAPSHOT_STATE_KNOWN) {
1779                         /* Ignore */
1780                         goto skip_msg;
1781                 }
1782
1783                 clk_snapshot = stream_msg->default_cs;
1784                 break;
1785         }
1786         default:
1787                 bt_common_abort();
1788         }
1789
1790         BT_ASSERT_DBG(clk_snapshot);
1791         ret = bt_clock_snapshot_get_ns_from_origin(clk_snapshot,
1792                 &msg_ns_from_origin);
1793         if (ret) {
1794                 status = BT_FUNC_STATUS_ERROR;
1795                 goto end;
1796         }
1797
1798         if (msg_ns_from_origin >= ns_from_origin) {
1799                 *got_first = true;
1800                 goto push_msg;
1801         }
1802
1803 skip_msg:
1804         /* This message won't be sent downstream. */
1805         switch (msg->type) {
1806         case BT_MESSAGE_TYPE_STREAM_BEGINNING:
1807         {
1808                 const struct bt_message_stream *stream_msg = (const void *) msg;
1809                 struct auto_seek_stream_state *stream_state;
1810
1811                 /* Update stream's state: stream began. */
1812                 stream_state = create_auto_seek_stream_state();
1813                 if (!stream_state) {
1814                         status = BT_FUNC_STATUS_MEMORY_ERROR;
1815                         goto end;
1816                 }
1817
1818                 stream_state->state = AUTO_SEEK_STREAM_STATE_STREAM_BEGAN;
1819
1820                 if (stream_msg->default_cs_state == BT_MESSAGE_STREAM_CLOCK_SNAPSHOT_STATE_KNOWN) {
1821                         stream_state->seen_clock_snapshot = true;
1822                 }
1823
1824                 BT_ASSERT_DBG(!bt_g_hash_table_contains(stream_states, stream_msg->stream));
1825                 g_hash_table_insert(stream_states, stream_msg->stream, stream_state);
1826                 break;
1827         }
1828         case BT_MESSAGE_TYPE_PACKET_BEGINNING:
1829         {
1830                 const struct bt_message_packet *packet_msg =
1831                         (const void *) msg;
1832                 struct auto_seek_stream_state *stream_state;
1833
1834                 /* Update stream's state: packet began. */
1835                 stream_state = g_hash_table_lookup(stream_states, packet_msg->packet->stream);
1836                 BT_ASSERT_DBG(stream_state);
1837                 BT_ASSERT_DBG(stream_state->state == AUTO_SEEK_STREAM_STATE_STREAM_BEGAN);
1838                 stream_state->state = AUTO_SEEK_STREAM_STATE_PACKET_BEGAN;
1839                 BT_ASSERT_DBG(!stream_state->packet);
1840                 stream_state->packet = packet_msg->packet;
1841
1842                 if (packet_msg->packet->stream->class->packets_have_beginning_default_clock_snapshot) {
1843                         stream_state->seen_clock_snapshot = true;
1844                 }
1845
1846                 break;
1847         }
1848         case BT_MESSAGE_TYPE_EVENT:
1849         {
1850                 const struct bt_message_event *event_msg = (const void *) msg;
1851                 struct auto_seek_stream_state *stream_state;
1852
1853                 stream_state = g_hash_table_lookup(stream_states,
1854                         event_msg->event->stream);
1855                 BT_ASSERT_DBG(stream_state);
1856
1857                 // HELPME: are we sure that event messages have clock snapshots at this point?
1858                 stream_state->seen_clock_snapshot = true;
1859
1860                 break;
1861         }
1862         case BT_MESSAGE_TYPE_PACKET_END:
1863         {
1864                 const struct bt_message_packet *packet_msg =
1865                         (const void *) msg;
1866                 struct auto_seek_stream_state *stream_state;
1867
1868                 /* Update stream's state: packet ended. */
1869                 stream_state = g_hash_table_lookup(stream_states, packet_msg->packet->stream);
1870                 BT_ASSERT_DBG(stream_state);
1871                 BT_ASSERT_DBG(stream_state->state == AUTO_SEEK_STREAM_STATE_PACKET_BEGAN);
1872                 stream_state->state = AUTO_SEEK_STREAM_STATE_STREAM_BEGAN;
1873                 BT_ASSERT_DBG(stream_state->packet);
1874                 stream_state->packet = NULL;
1875
1876                 if (packet_msg->packet->stream->class->packets_have_end_default_clock_snapshot) {
1877                         stream_state->seen_clock_snapshot = true;
1878                 }
1879
1880                 break;
1881         }
1882         case BT_MESSAGE_TYPE_STREAM_END:
1883         {
1884                 const struct bt_message_stream *stream_msg = (const void *) msg;
1885                 struct auto_seek_stream_state *stream_state;
1886
1887                 stream_state = g_hash_table_lookup(stream_states, stream_msg->stream);
1888                 BT_ASSERT_DBG(stream_state);
1889                 BT_ASSERT_DBG(stream_state->state == AUTO_SEEK_STREAM_STATE_STREAM_BEGAN);
1890                 BT_ASSERT_DBG(!stream_state->packet);
1891
1892                 /* Update stream's state: this stream doesn't exist anymore. */
1893                 g_hash_table_remove(stream_states, stream_msg->stream);
1894                 break;
1895         }
1896         case BT_MESSAGE_TYPE_DISCARDED_EVENTS:
1897         case BT_MESSAGE_TYPE_DISCARDED_PACKETS:
1898         {
1899                 const struct bt_message_discarded_items *discarded_msg =
1900                         (const void *) msg;
1901                 struct auto_seek_stream_state *stream_state;
1902
1903                 stream_state = g_hash_table_lookup(stream_states, discarded_msg->stream);
1904                 BT_ASSERT_DBG(stream_state);
1905
1906                 if ((msg->type == BT_MESSAGE_TYPE_DISCARDED_EVENTS && discarded_msg->stream->class->discarded_events_have_default_clock_snapshots) ||
1907                         (msg->type == BT_MESSAGE_TYPE_DISCARDED_PACKETS && discarded_msg->stream->class->discarded_packets_have_default_clock_snapshots)) {
1908                         stream_state->seen_clock_snapshot = true;
1909                 }
1910
1911                 break;
1912         }
1913         default:
1914                 break;
1915         }
1916
1917         bt_object_put_ref_no_null_check(msg);
1918         msg = NULL;
1919         goto end;
1920
1921 push_msg:
1922         g_queue_push_tail(iterator->auto_seek.msgs, (void *) msg);
1923         msg = NULL;
1924
1925 end:
1926         BT_ASSERT_DBG(!msg || status != BT_FUNC_STATUS_OK);
1927         return status;
1928 }
1929
1930 static
1931 int find_message_ge_ns_from_origin(
1932                 struct bt_message_iterator *iterator,
1933                 int64_t ns_from_origin, GHashTable *stream_states)
1934 {
1935         int status = BT_FUNC_STATUS_OK;
1936         enum bt_message_iterator_state init_state =
1937                 iterator->state;
1938         const struct bt_message *messages[MSG_BATCH_SIZE];
1939         uint64_t user_count = 0;
1940         uint64_t i;
1941         bool got_first = false;
1942
1943         BT_ASSERT_DBG(iterator);
1944         memset(&messages[0], 0, sizeof(messages[0]) * MSG_BATCH_SIZE);
1945
1946         /*
1947          * Make this iterator temporarily active (not seeking) to call
1948          * the "next" method.
1949          */
1950         set_msg_iterator_state(iterator,
1951                 BT_MESSAGE_ITERATOR_STATE_ACTIVE);
1952
1953         BT_ASSERT_DBG(iterator->methods.next);
1954
1955         while (!got_first) {
1956                 /*
1957                  * Call the user's "next" method to get the next
1958                  * messages and status.
1959                  */
1960                 status = call_iterator_next_method(iterator,
1961                         &messages[0], MSG_BATCH_SIZE, &user_count);
1962                 BT_LOGD("User method returned: status=%s",
1963                         bt_common_func_status_string(status));
1964                 if (status < 0) {
1965                         BT_LIB_LOGW_APPEND_CAUSE(
1966                                 "Component input port message iterator's \"next\" method failed: "
1967                                 "%![iter-]+i, status=%s",
1968                                 iterator, bt_common_func_status_string(status));
1969                 }
1970
1971                 /*
1972                  * The user's "next" method must not do any action which
1973                  * would change the iterator's state.
1974                  */
1975                 BT_ASSERT_DBG(iterator->state ==
1976                         BT_MESSAGE_ITERATOR_STATE_ACTIVE);
1977
1978                 switch (status) {
1979                 case BT_FUNC_STATUS_OK:
1980                         BT_ASSERT_POST_DEV(NEXT_METHOD_NAME,
1981                                 "count-lteq-capacity",
1982                                 user_count <= MSG_BATCH_SIZE,
1983                                 "Invalid returned message count: greater than "
1984                                 "batch size: count=%" PRIu64 ", batch-size=%u",
1985                                 user_count, MSG_BATCH_SIZE);
1986                         break;
1987                 case BT_FUNC_STATUS_AGAIN:
1988                 case BT_FUNC_STATUS_ERROR:
1989                 case BT_FUNC_STATUS_MEMORY_ERROR:
1990                 case BT_FUNC_STATUS_END:
1991                         goto end;
1992                 default:
1993                         bt_common_abort();
1994                 }
1995
1996                 for (i = 0; i < user_count; i++) {
1997                         if (got_first) {
1998                                 g_queue_push_tail(iterator->auto_seek.msgs,
1999                                         (void *) messages[i]);
2000                                 messages[i] = NULL;
2001                                 continue;
2002                         }
2003
2004                         status = auto_seek_handle_message(iterator,
2005                                 ns_from_origin, messages[i], &got_first,
2006                                 stream_states);
2007                         if (status == BT_FUNC_STATUS_OK) {
2008                                 /* Message was either pushed or moved */
2009                                 messages[i] = NULL;
2010                         } else {
2011                                 goto end;
2012                         }
2013                 }
2014         }
2015
2016 end:
2017         for (i = 0; i < user_count; i++) {
2018                 if (messages[i]) {
2019                         bt_object_put_ref_no_null_check(messages[i]);
2020                 }
2021         }
2022
2023         set_msg_iterator_state(iterator, init_state);
2024         return status;
2025 }
2026
2027 /*
2028  * This function is installed as the iterator's next callback after we have
2029  * auto-sought (sought to the beginning and fast-forwarded) to send the
2030  * messages saved in iterator->auto_seek.msgs.  Once this is done, the original
2031  * next callback is put back.
2032  */
2033
2034 static
2035 enum bt_message_iterator_class_next_method_status post_auto_seek_next(
2036                 struct bt_message_iterator *iterator,
2037                 bt_message_array_const msgs, uint64_t capacity,
2038                 uint64_t *count)
2039 {
2040         BT_ASSERT(!g_queue_is_empty(iterator->auto_seek.msgs));
2041         *count = 0;
2042
2043         /*
2044          * Move auto-seek messages to the output array (which is this
2045          * iterator's base message array).
2046          */
2047         while (capacity > 0 && !g_queue_is_empty(iterator->auto_seek.msgs)) {
2048                 msgs[*count] = g_queue_pop_head(iterator->auto_seek.msgs);
2049                 capacity--;
2050                 (*count)++;
2051         }
2052
2053         BT_ASSERT(*count > 0);
2054
2055         if (g_queue_is_empty(iterator->auto_seek.msgs)) {
2056                 /* No more auto-seek messages, restore user's next callback. */
2057                 BT_ASSERT(iterator->auto_seek.original_next_callback);
2058                 iterator->methods.next = iterator->auto_seek.original_next_callback;
2059                 iterator->auto_seek.original_next_callback = NULL;
2060         }
2061
2062         return BT_FUNC_STATUS_OK;
2063 }
2064
2065 static inline
2066 int clock_raw_value_from_ns_from_origin(const bt_clock_class *clock_class,
2067                 int64_t ns_from_origin, uint64_t *raw_value)
2068 {
2069
2070         int64_t cc_offset_s = clock_class->offset_seconds;
2071         uint64_t cc_offset_cycles = clock_class->offset_cycles;
2072         uint64_t cc_freq = clock_class->frequency;
2073
2074         return bt_common_clock_value_from_ns_from_origin(cc_offset_s,
2075                 cc_offset_cycles, cc_freq, ns_from_origin, raw_value);
2076 }
2077
2078 static
2079 bool message_iterator_can_seek_ns_from_origin(
2080                 struct bt_message_iterator *iterator,
2081                 int64_t ns_from_origin)
2082 {
2083         enum bt_message_iterator_can_seek_ns_from_origin_status status;
2084         bt_bool can_seek;
2085
2086         status = bt_message_iterator_can_seek_ns_from_origin(
2087                 iterator, ns_from_origin, &can_seek);
2088         if (status != BT_FUNC_STATUS_OK) {
2089                 can_seek = BT_FALSE;
2090         }
2091
2092         return can_seek;
2093 }
2094
2095 #define SEEK_NS_FROM_ORIGIN_METHOD_NAME                                 \
2096         "bt_message_iterator_class_seek_ns_from_origin_method"
2097
2098
2099 BT_EXPORT
2100 enum bt_message_iterator_seek_ns_from_origin_status
2101 bt_message_iterator_seek_ns_from_origin(
2102                 struct bt_message_iterator *iterator,
2103                 int64_t ns_from_origin)
2104 {
2105         int status;
2106         GHashTable *stream_states = NULL;
2107         bt_bool can_seek_by_itself;
2108
2109         BT_ASSERT_PRE_NO_ERROR();
2110         BT_ASSERT_PRE_MSG_ITER_NON_NULL(iterator);
2111         BT_ASSERT_PRE_ITER_HAS_STATE_TO_SEEK(iterator);
2112         BT_ASSERT_PRE("graph-is-configured",
2113                 bt_component_borrow_graph(iterator->upstream_component)->config_state !=
2114                         BT_GRAPH_CONFIGURATION_STATE_CONFIGURING,
2115                 "Graph is not configured: %!+g",
2116                 bt_component_borrow_graph(iterator->upstream_component));
2117         /* The iterator must be able to seek ns from origin one way or another. */
2118         BT_ASSERT_PRE("can-seek-ns-from-origin",
2119                 message_iterator_can_seek_ns_from_origin(iterator, ns_from_origin),
2120                 "Message iterator cannot seek nanoseconds from origin: %!+i, "
2121                 "ns-from-origin=%" PRId64, iterator, ns_from_origin);
2122         set_msg_iterator_state(iterator,
2123                 BT_MESSAGE_ITERATOR_STATE_SEEKING);
2124
2125         /*
2126          * We are seeking, reset our expectations about how the following
2127          * messages should look like.
2128          */
2129         reset_iterator_expectations(iterator);
2130
2131         /* Check if the iterator can seek by itself.  If not we'll use autoseek. */
2132         if (iterator->methods.can_seek_ns_from_origin) {
2133                 bt_message_iterator_class_can_seek_ns_from_origin_method_status
2134                         can_seek_status;
2135
2136                 can_seek_status =
2137                         iterator->methods.can_seek_ns_from_origin(
2138                                 iterator, ns_from_origin, &can_seek_by_itself);
2139                 if (can_seek_status != BT_FUNC_STATUS_OK) {
2140                         status = can_seek_status;
2141                         goto end;
2142                 }
2143         } else {
2144                 can_seek_by_itself = false;
2145         }
2146
2147         if (can_seek_by_itself) {
2148                 /* The iterator knows how to seek to a particular time, let it handle this. */
2149                 BT_ASSERT(iterator->methods.seek_ns_from_origin);
2150                 BT_LIB_LOGD("Calling user's \"seek nanoseconds from origin\" method: "
2151                         "%![iter-]+i, ns=%" PRId64, iterator, ns_from_origin);
2152                 status = iterator->methods.seek_ns_from_origin(iterator,
2153                         ns_from_origin);
2154                 BT_LOGD("User method returned: status=%s",
2155                         bt_common_func_status_string(status));
2156                 BT_ASSERT_POST(SEEK_NS_FROM_ORIGIN_METHOD_NAME, "valid-status",
2157                         status == BT_FUNC_STATUS_OK ||
2158                         status == BT_FUNC_STATUS_ERROR ||
2159                         status == BT_FUNC_STATUS_MEMORY_ERROR ||
2160                         status == BT_FUNC_STATUS_AGAIN,
2161                         "Unexpected status: %![iter-]+i, status=%s",
2162                         iterator, bt_common_func_status_string(status));
2163                 BT_ASSERT_POST_NO_ERROR_IF_NO_ERROR_STATUS(
2164                         SEEK_NS_FROM_ORIGIN_METHOD_NAME, status);
2165                 if (status < 0) {
2166                         BT_LIB_LOGW_APPEND_CAUSE(
2167                                 "Component input port message iterator's \"seek nanoseconds from origin\" method failed: "
2168                                 "%![iter-]+i, status=%s",
2169                                 iterator, bt_common_func_status_string(status));
2170                 }
2171         } else {
2172                 /*
2173                  * The iterator doesn't know how to seek by itself to a
2174                  * particular time.  We will seek to the beginning and fast
2175                  * forward to the right place.
2176                  */
2177                 enum bt_message_iterator_class_can_seek_beginning_method_status can_seek_status;
2178                 bt_bool can_seek_beginning;
2179
2180                 can_seek_status = iterator->methods.can_seek_beginning(iterator,
2181                         &can_seek_beginning);
2182                 BT_ASSERT(can_seek_status == BT_FUNC_STATUS_OK);
2183                 BT_ASSERT(can_seek_beginning);
2184                 BT_ASSERT(iterator->methods.seek_beginning);
2185                 BT_LIB_LOGD("Calling user's \"seek beginning\" method: %!+i",
2186                         iterator);
2187                 status = iterator->methods.seek_beginning(iterator);
2188                 BT_LOGD("User method returned: status=%s",
2189                         bt_common_func_status_string(status));
2190                 BT_ASSERT_POST(SEEK_BEGINNING_METHOD_NAME, "valid-status",
2191                         status == BT_FUNC_STATUS_OK ||
2192                         status == BT_FUNC_STATUS_ERROR ||
2193                         status == BT_FUNC_STATUS_MEMORY_ERROR ||
2194                         status == BT_FUNC_STATUS_AGAIN,
2195                         "Unexpected status: %![iter-]+i, status=%s",
2196                         iterator, bt_common_func_status_string(status));
2197                 if (status < 0) {
2198                         BT_LIB_LOGW_APPEND_CAUSE(
2199                                 "Component input port message iterator's \"seek beginning\" method failed: "
2200                                 "%![iter-]+i, status=%s",
2201                                 iterator, bt_common_func_status_string(status));
2202                 }
2203
2204                 clear_per_stream_state(iterator);
2205
2206                 switch (status) {
2207                 case BT_FUNC_STATUS_OK:
2208                         break;
2209                 case BT_FUNC_STATUS_ERROR:
2210                 case BT_FUNC_STATUS_MEMORY_ERROR:
2211                 case BT_FUNC_STATUS_AGAIN:
2212                         goto end;
2213                 default:
2214                         bt_common_abort();
2215                 }
2216
2217                 /*
2218                  * Find the first message which has a default clock
2219                  * snapshot greater than or equal to the requested
2220                  * seeking time, and move the received messages from
2221                  * this point in the batch to this iterator's auto-seek
2222                  * message queue.
2223                  */
2224                 while (!g_queue_is_empty(iterator->auto_seek.msgs)) {
2225                         bt_object_put_ref_no_null_check(
2226                                 g_queue_pop_tail(iterator->auto_seek.msgs));
2227                 }
2228
2229                 stream_states = create_auto_seek_stream_states();
2230                 if (!stream_states) {
2231                         BT_LIB_LOGE_APPEND_CAUSE(
2232                                 "Failed to allocate one GHashTable.");
2233                         status = BT_FUNC_STATUS_MEMORY_ERROR;
2234                         goto end;
2235                 }
2236
2237                 status = find_message_ge_ns_from_origin(iterator,
2238                         ns_from_origin, stream_states);
2239                 switch (status) {
2240                 case BT_FUNC_STATUS_OK:
2241                 case BT_FUNC_STATUS_END:
2242                 {
2243                         GHashTableIter iter;
2244                         gpointer key, value;
2245
2246                         /*
2247                          * If some streams exist at the seek time, prepend the
2248                          * required messages to put those streams in the right
2249                          * state.
2250                          */
2251                         g_hash_table_iter_init(&iter, stream_states);
2252                         while (g_hash_table_iter_next (&iter, &key, &value)) {
2253                                 const bt_stream *stream = key;
2254                                 struct auto_seek_stream_state *stream_state =
2255                                         (struct auto_seek_stream_state *) value;
2256                                 bt_message *msg;
2257                                 const bt_clock_class *clock_class = bt_stream_class_borrow_default_clock_class_const(
2258                                         bt_stream_borrow_class_const(stream));
2259                                 /* Initialize to silence maybe-uninitialized warning. */
2260                                 uint64_t raw_value = 0;
2261
2262                                 /*
2263                                  * If we haven't seen a message with a clock snapshot, we don't know if our seek time is within
2264                                  * the clock's range, so it wouldn't be safe to try to convert ns_from_origin to a clock value.
2265                                  *
2266                                  * Also, it would be a bit of a lie to generate a stream begin message with the seek time as its
2267                                  * clock snapshot, because we don't really know if the stream existed at that time.  If we have
2268                                  * seen a message with a clock snapshot in our seeking, then we are sure that the
2269                                  * seek time is not below the clock range, and we know the stream was active at that
2270                                  * time (and that we cut it short).
2271                                  */
2272                                 if (stream_state->seen_clock_snapshot) {
2273                                         if (clock_raw_value_from_ns_from_origin(clock_class, ns_from_origin, &raw_value) != 0) {
2274                                                 BT_LIB_LOGW("Could not convert nanoseconds from origin to clock value: ns-from-origin=%" PRId64 ", %![cc-]+K",
2275                                                         ns_from_origin, clock_class);
2276                                                 status = BT_FUNC_STATUS_ERROR;
2277                                                 goto end;
2278                                         }
2279                                 }
2280
2281                                 switch (stream_state->state) {
2282                                 case AUTO_SEEK_STREAM_STATE_PACKET_BEGAN:
2283                                         BT_ASSERT(stream_state->packet);
2284                                         BT_LIB_LOGD("Creating packet message: %![packet-]+a", stream_state->packet);
2285
2286                                         if (stream->class->packets_have_beginning_default_clock_snapshot) {
2287                                                 /*
2288                                                  * If we are in the PACKET_BEGAN state, it means we have seen a "packet beginning"
2289                                                  * message.  If "packet beginning" packets have clock snapshots, then we must have
2290                                                  * seen a clock snapshot.
2291                                                  */
2292                                                 BT_ASSERT(stream_state->seen_clock_snapshot);
2293
2294                                                 msg = bt_message_packet_beginning_create_with_default_clock_snapshot(
2295                                                         (bt_self_message_iterator *) iterator, stream_state->packet, raw_value);
2296                                         } else {
2297                                                 msg = bt_message_packet_beginning_create((bt_self_message_iterator *) iterator,
2298                                                                 stream_state->packet);
2299                                         }
2300
2301                                         if (!msg) {
2302                                                 status = BT_FUNC_STATUS_MEMORY_ERROR;
2303                                                 goto end;
2304                                         }
2305
2306                                         g_queue_push_head(iterator->auto_seek.msgs, msg);
2307                                         msg = NULL;
2308                                         /* fall-thru */
2309
2310                                 case AUTO_SEEK_STREAM_STATE_STREAM_BEGAN:
2311                                         msg = bt_message_stream_beginning_create(
2312                                                 (bt_self_message_iterator *) iterator, stream);
2313                                         if (!msg) {
2314                                                 status = BT_FUNC_STATUS_MEMORY_ERROR;
2315                                                 goto end;
2316                                         }
2317
2318                                         if (stream_state->seen_clock_snapshot) {
2319                                                 bt_message_stream_beginning_set_default_clock_snapshot(msg, raw_value);
2320                                         }
2321
2322                                         g_queue_push_head(iterator->auto_seek.msgs, msg);
2323                                         msg = NULL;
2324                                         break;
2325                                 }
2326                         }
2327
2328                         /*
2329                          * If there are messages in the auto-seek
2330                          * message queue, replace the user's "next"
2331                          * method with a custom, temporary "next" method
2332                          * which returns them.
2333                          */
2334                         if (!g_queue_is_empty(iterator->auto_seek.msgs)) {
2335                                 BT_ASSERT(!iterator->auto_seek.original_next_callback);
2336                                 iterator->auto_seek.original_next_callback = iterator->methods.next;
2337
2338                                 iterator->methods.next =
2339                                         (bt_message_iterator_next_method)
2340                                                 post_auto_seek_next;
2341                         }
2342
2343                         /*
2344                          * `BT_FUNC_STATUS_END` becomes
2345                          * `BT_FUNC_STATUS_OK`: the next
2346                          * time this iterator's "next" method is called,
2347                          * it will return
2348                          * `BT_FUNC_STATUS_END`.
2349                          */
2350                         status = BT_FUNC_STATUS_OK;
2351                         break;
2352                 }
2353                 case BT_FUNC_STATUS_ERROR:
2354                 case BT_FUNC_STATUS_MEMORY_ERROR:
2355                 case BT_FUNC_STATUS_AGAIN:
2356                         goto end;
2357                 default:
2358                         bt_common_abort();
2359                 }
2360         }
2361
2362         clear_per_stream_state(iterator);
2363
2364         /*
2365          * The following messages returned by the next method (including
2366          * post_auto_seek_next) must be after (or at) `ns_from_origin`.
2367          */
2368         iterator->last_ns_from_origin = ns_from_origin;
2369
2370 end:
2371         if (stream_states) {
2372                 destroy_auto_seek_stream_states(stream_states);
2373                 stream_states = NULL;
2374         }
2375
2376         set_iterator_state_after_seeking(iterator, status);
2377         return status;
2378 }
2379
2380 BT_EXPORT
2381 bt_bool bt_self_message_iterator_is_interrupted(
2382                 const struct bt_self_message_iterator *self_msg_iter)
2383 {
2384         const struct bt_message_iterator *iterator =
2385                 (const void *) self_msg_iter;
2386
2387         BT_ASSERT_PRE_MSG_ITER_NON_NULL(iterator);
2388         return (bt_bool) bt_graph_is_interrupted(iterator->graph);
2389 }
2390
2391 BT_EXPORT
2392 void bt_message_iterator_get_ref(
2393                 const struct bt_message_iterator *iterator)
2394 {
2395         bt_object_get_ref(iterator);
2396 }
2397
2398 BT_EXPORT
2399 void bt_message_iterator_put_ref(
2400                 const struct bt_message_iterator *iterator)
2401 {
2402         bt_object_put_ref(iterator);
2403 }