src/lib/graph/iterator.c

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