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