src/lib/graph/iterator.c

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