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/lib-logging.h"
  26
  27 #include "compat/compiler.h"
  28 #include "lib/trace-ir/clock-class.h"
  29 #include "lib/trace-ir/clock-snapshot.h"
  30 #include <babeltrace2/trace-ir/field.h>
  31 #include <babeltrace2/trace-ir/event-const.h>
  32 #include "lib/trace-ir/event.h"
  33 #include <babeltrace2/trace-ir/packet-const.h>
  34 #include "lib/trace-ir/packet.h"
  35 #include "lib/trace-ir/stream.h"
  36 #include <babeltrace2/graph/connection-const.h>
  37 #include <babeltrace2/graph/component-const.h>
  38 #include <babeltrace2/graph/component-sink-const.h>
  39 #include <babeltrace2/graph/message-const.h>
  40 #include <babeltrace2/graph/message-iterator-const.h>
  41 #include <babeltrace2/graph/self-component-port-input-message-iterator.h>
  42 #include <babeltrace2/graph/port-output-message-iterator.h>
  43 #include <babeltrace2/graph/message-event-const.h>
  44 #include <babeltrace2/graph/message-packet-beginning-const.h>
  45 #include <babeltrace2/graph/message-packet-end-const.h>
  46 #include <babeltrace2/graph/message-stream-beginning-const.h>
  47 #include <babeltrace2/graph/message-stream-end-const.h>
  48 #include <babeltrace2/graph/port-const.h>
  49 #include <babeltrace2/graph/graph.h>
  50 #include <babeltrace2/graph/graph-const.h>
  51 #include <babeltrace2/types.h>
  52 #include "common/assert.h"
  53 #include "lib/assert-pre.h"
  54 #include <stdint.h>
  55 #include <inttypes.h>
  56 #include <stdlib.h>
  57
  58 #include "component-class.h"
  59 #include "component-class-sink-colander.h"
  60 #include "component.h"
  61 #include "component-sink.h"
  62 #include "component-source.h"
  63 #include "connection.h"
  64 #include "graph.h"
  65 #include "message/discarded-items.h"
  66 #include "message/event.h"
  67 #include "message/iterator.h"
  68 #include "message/message.h"
  69 #include "message/message-iterator-inactivity.h"
  70 #include "message/stream.h"
  71 #include "message/packet.h"
  72 #include "message/stream-activity.h"
  73
  74 /*
  75  * TODO: Use graph's state (number of active iterators, etc.) and
  76  * possibly system specifications to make a better guess than this.
  77  */
  78 #define MSG_BATCH_SIZE  15
  79
  80 #define BT_ASSERT_PRE_ITER_HAS_STATE_TO_SEEK(_iter)                     \
  81         BT_ASSERT_PRE((_iter)->state == BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_ACTIVE || \
  82                 (_iter)->state == BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_ENDED || \
  83                 (_iter)->state == BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_LAST_SEEKING_RETURNED_AGAIN || \
  84                 (_iter)->state == BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_LAST_SEEKING_RETURNED_ERROR, \
  85                 "Message iterator is in the wrong state: %!+i", _iter)
  86
  87 static inline
  88 void set_self_comp_port_input_msg_iterator_state(
  89                 struct bt_self_component_port_input_message_iterator *iterator,
  90                 enum bt_self_component_port_input_message_iterator_state state)
  91 {
  92         BT_ASSERT(iterator);
  93         BT_LIB_LOGD("Updating message iterator's state: new-state=%s",
  94                 bt_self_component_port_input_message_iterator_state_string(state));
  95         iterator->state = state;
  96 }
  97
  98 static
  99 void destroy_base_message_iterator(struct bt_object *obj)
 100 {
 101         struct bt_message_iterator *iterator = (void *) obj;
 102
 103         BT_ASSERT(iterator);
 104
 105         if (iterator->msgs) {
 106                 g_ptr_array_free(iterator->msgs, TRUE);
 107                 iterator->msgs = NULL;
 108         }
 109
 110         g_free(iterator);
 111 }
 112
 113 static
 114 void bt_self_component_port_input_message_iterator_destroy(struct bt_object *obj)
 115 {
 116         struct bt_self_component_port_input_message_iterator *iterator;
 117
 118         BT_ASSERT(obj);
 119
 120         /*
 121          * The message iterator's reference count is 0 if we're
 122          * here. Increment it to avoid a double-destroy (possibly
 123          * infinitely recursive). This could happen for example if the
 124          * message iterator's finalization function does
 125          * bt_object_get_ref() (or anything that causes
 126          * bt_object_get_ref() to be called) on itself (ref. count goes
 127          * from 0 to 1), and then bt_object_put_ref(): the reference
 128          * count would go from 1 to 0 again and this function would be
 129          * called again.
 130          */
 131         obj->ref_count++;
 132         iterator = (void *) obj;
 133         BT_LIB_LOGI("Destroying self component input port message iterator object: "
 134                 "%!+i", iterator);
 135         bt_self_component_port_input_message_iterator_try_finalize(iterator);
 136
 137         if (iterator->connection) {
 138                 /*
 139                  * Remove ourself from the originating connection so
 140                  * that it does not try to finalize a dangling pointer
 141                  * later.
 142                  */
 143                 bt_connection_remove_iterator(iterator->connection, iterator);
 144                 iterator->connection = NULL;
 145         }
 146
 147         if (iterator->auto_seek_msgs) {
 148                 while (!g_queue_is_empty(iterator->auto_seek_msgs)) {
 149                         bt_object_put_no_null_check(
 150                                 g_queue_pop_tail(iterator->auto_seek_msgs));
 151                 }
 152
 153                 g_queue_free(iterator->auto_seek_msgs);
 154                 iterator->auto_seek_msgs = NULL;
 155         }
 156
 157         destroy_base_message_iterator(obj);
 158 }
 159
 160 BT_HIDDEN
 161 void bt_self_component_port_input_message_iterator_try_finalize(
 162                 struct bt_self_component_port_input_message_iterator *iterator)
 163 {
 164         typedef void (*method_t)(void *);
 165
 166         struct bt_component_class *comp_class = NULL;
 167         method_t method = NULL;
 168
 169         BT_ASSERT(iterator);
 170
 171         switch (iterator->state) {
 172         case BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_NON_INITIALIZED:
 173                 /* Skip user finalization if user initialization failed */
 174                 BT_LIB_LOGD("Not finalizing non-initialized message iterator: "
 175                         "%!+i", iterator);
 176                 goto end;
 177         case BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_FINALIZED:
 178                 /* Already finalized */
 179                 BT_LIB_LOGD("Not finalizing message iterator: already finalized: "
 180                         "%!+i", iterator);
 181                 goto end;
 182         case BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_FINALIZING:
 183                 /* Already finalized */
 184                 BT_LIB_LOGF("Message iterator is already being finalized: "
 185                         "%!+i", iterator);
 186                 abort();
 187         default:
 188                 break;
 189         }
 190
 191         BT_LIB_LOGD("Finalizing message iterator: %!+i", iterator);
 192         set_self_comp_port_input_msg_iterator_state(iterator,
 193                 BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_FINALIZING);
 194         BT_ASSERT(iterator->upstream_component);
 195         comp_class = iterator->upstream_component->class;
 196
 197         /* Call user-defined destroy method */
 198         switch (comp_class->type) {
 199         case BT_COMPONENT_CLASS_TYPE_SOURCE:
 200         {
 201                 struct bt_component_class_source *src_comp_cls =
 202                         (void *) comp_class;
 203
 204                 method = (method_t) src_comp_cls->methods.msg_iter_finalize;
 205                 break;
 206         }
 207         case BT_COMPONENT_CLASS_TYPE_FILTER:
 208         {
 209                 struct bt_component_class_filter *flt_comp_cls =
 210                         (void *) comp_class;
 211
 212                 method = (method_t) flt_comp_cls->methods.msg_iter_finalize;
 213                 break;
 214         }
 215         default:
 216                 /* Unreachable */
 217                 abort();
 218         }
 219
 220         if (method) {
 221                 BT_LIB_LOGD("Calling user's finalization method: %!+i",
 222                         iterator);
 223                 method(iterator);
 224         }
 225
 226         iterator->upstream_component = NULL;
 227         iterator->upstream_port = NULL;
 228         set_self_comp_port_input_msg_iterator_state(iterator,
 229                 BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_FINALIZED);
 230         BT_LIB_LOGD("Finalized message iterator: %!+i", iterator);
 231
 232 end:
 233         return;
 234 }
 235
 236 BT_HIDDEN
 237 void bt_self_component_port_input_message_iterator_set_connection(
 238                 struct bt_self_component_port_input_message_iterator *iterator,
 239                 struct bt_connection *connection)
 240 {
 241         BT_ASSERT(iterator);
 242         iterator->connection = connection;
 243         BT_LIB_LOGI("Set message iterator's connection: "
 244                 "%![iter-]+i, %![conn-]+x", iterator, connection);
 245 }
 246
 247 static
 248 int init_message_iterator(struct bt_message_iterator *iterator,
 249                 enum bt_message_iterator_type type,
 250                 bt_object_release_func destroy)
 251 {
 252         int ret = 0;
 253
 254         bt_object_init_shared(&iterator->base, destroy);
 255         iterator->type = type;
 256         iterator->msgs = g_ptr_array_new();
 257         if (!iterator->msgs) {
 258                 BT_LOGE_STR("Failed to allocate a GPtrArray.");
 259                 ret = -1;
 260                 goto end;
 261         }
 262
 263         g_ptr_array_set_size(iterator->msgs, MSG_BATCH_SIZE);
 264
 265 end:
 266         return ret;
 267 }
 268
 269 static
 270 bt_bool can_seek_ns_from_origin_true(
 271                 struct bt_self_component_port_input_message_iterator *iterator,
 272                 int64_t ns_from_origin)
 273 {
 274         return BT_TRUE;
 275 }
 276
 277 static
 278 bt_bool can_seek_beginning_true(
 279                 struct bt_self_component_port_input_message_iterator *iterator)
 280 {
 281         return BT_TRUE;
 282 }
 283
 284 static
 285 struct bt_self_component_port_input_message_iterator *
 286 bt_self_component_port_input_message_iterator_create_initial(
 287                 struct bt_component *upstream_comp,
 288                 struct bt_port *upstream_port)
 289 {
 290         int ret;
 291         struct bt_self_component_port_input_message_iterator *iterator = NULL;
 292
 293         BT_ASSERT(upstream_comp);
 294         BT_ASSERT(upstream_port);
 295         BT_ASSERT(bt_port_is_connected(upstream_port));
 296         BT_LIB_LOGI("Creating initial message iterator on self component input port: "
 297                 "%![up-comp-]+c, %![up-port-]+p", upstream_comp, upstream_port);
 298         BT_ASSERT(bt_component_get_class_type(upstream_comp) ==
 299                 BT_COMPONENT_CLASS_TYPE_SOURCE ||
 300                 bt_component_get_class_type(upstream_comp) ==
 301                 BT_COMPONENT_CLASS_TYPE_FILTER);
 302         iterator = g_new0(
 303                 struct bt_self_component_port_input_message_iterator, 1);
 304         if (!iterator) {
 305                 BT_LOGE_STR("Failed to allocate one self component input port "
 306                         "message iterator.");
 307                 goto end;
 308         }
 309
 310         ret = init_message_iterator((void *) iterator,
 311                 BT_MESSAGE_ITERATOR_TYPE_SELF_COMPONENT_PORT_INPUT,
 312                 bt_self_component_port_input_message_iterator_destroy);
 313         if (ret) {
 314                 /* init_message_iterator() logs errors */
 315                 BT_OBJECT_PUT_REF_AND_RESET(iterator);
 316                 goto end;
 317         }
 318
 319         iterator->auto_seek_msgs = g_queue_new();
 320         if (!iterator->auto_seek_msgs) {
 321                 BT_LOGE_STR("Failed to allocate a GQueue.");
 322                 ret = -1;
 323                 goto end;
 324         }
 325
 326         iterator->upstream_component = upstream_comp;
 327         iterator->upstream_port = upstream_port;
 328         iterator->connection = iterator->upstream_port->connection;
 329         iterator->graph = bt_component_borrow_graph(upstream_comp);
 330         set_self_comp_port_input_msg_iterator_state(iterator,
 331                 BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_NON_INITIALIZED);
 332
 333         switch (iterator->upstream_component->class->type) {
 334         case BT_COMPONENT_CLASS_TYPE_SOURCE:
 335         {
 336                 struct bt_component_class_source *src_comp_cls =
 337                         (void *) iterator->upstream_component->class;
 338
 339                 iterator->methods.next =
 340                         (bt_self_component_port_input_message_iterator_next_method)
 341                                 src_comp_cls->methods.msg_iter_next;
 342                 iterator->methods.seek_ns_from_origin =
 343                         (bt_self_component_port_input_message_iterator_seek_ns_from_origin_method)
 344                                 src_comp_cls->methods.msg_iter_seek_ns_from_origin;
 345                 iterator->methods.seek_beginning =
 346                         (bt_self_component_port_input_message_iterator_seek_beginning_method)
 347                                 src_comp_cls->methods.msg_iter_seek_beginning;
 348                 iterator->methods.can_seek_ns_from_origin =
 349                         (bt_self_component_port_input_message_iterator_can_seek_ns_from_origin_method)
 350                                 src_comp_cls->methods.msg_iter_can_seek_ns_from_origin;
 351                 iterator->methods.can_seek_beginning =
 352                         (bt_self_component_port_input_message_iterator_can_seek_beginning_method)
 353                                 src_comp_cls->methods.msg_iter_can_seek_beginning;
 354                 break;
 355         }
 356         case BT_COMPONENT_CLASS_TYPE_FILTER:
 357         {
 358                 struct bt_component_class_filter *flt_comp_cls =
 359                         (void *) iterator->upstream_component->class;
 360
 361                 iterator->methods.next =
 362                         (bt_self_component_port_input_message_iterator_next_method)
 363                                 flt_comp_cls->methods.msg_iter_next;
 364                 iterator->methods.seek_ns_from_origin =
 365                         (bt_self_component_port_input_message_iterator_seek_ns_from_origin_method)
 366                                 flt_comp_cls->methods.msg_iter_seek_ns_from_origin;
 367                 iterator->methods.seek_beginning =
 368                         (bt_self_component_port_input_message_iterator_seek_beginning_method)
 369                                 flt_comp_cls->methods.msg_iter_seek_beginning;
 370                 iterator->methods.can_seek_ns_from_origin =
 371                         (bt_self_component_port_input_message_iterator_can_seek_ns_from_origin_method)
 372                                 flt_comp_cls->methods.msg_iter_can_seek_ns_from_origin;
 373                 iterator->methods.can_seek_beginning =
 374                         (bt_self_component_port_input_message_iterator_can_seek_beginning_method)
 375                                 flt_comp_cls->methods.msg_iter_can_seek_beginning;
 376                 break;
 377         }
 378         default:
 379                 abort();
 380         }
 381
 382         if (iterator->methods.seek_ns_from_origin &&
 383                         !iterator->methods.can_seek_ns_from_origin) {
 384                 iterator->methods.can_seek_ns_from_origin =
 385                         (bt_self_component_port_input_message_iterator_can_seek_ns_from_origin_method)
 386                                 can_seek_ns_from_origin_true;
 387         }
 388
 389         if (iterator->methods.seek_beginning &&
 390                         !iterator->methods.can_seek_beginning) {
 391                 iterator->methods.can_seek_beginning =
 392                         (bt_self_component_port_input_message_iterator_seek_beginning_method)
 393                                 can_seek_beginning_true;
 394         }
 395
 396         BT_LIB_LOGI("Created initial message iterator on self component input port: "
 397                 "%![up-port-]+p, %![up-comp-]+c, %![iter-]+i",
 398                 upstream_port, upstream_comp, iterator);
 399
 400 end:
 401         return iterator;
 402 }
 403
 404 struct bt_self_component_port_input_message_iterator *
 405 bt_self_component_port_input_message_iterator_create(
 406                 struct bt_self_component_port_input *self_port)
 407 {
 408         typedef enum bt_self_message_iterator_status (*init_method_t)(
 409                         void *, void *, void *);
 410
 411         init_method_t init_method = NULL;
 412         struct bt_self_component_port_input_message_iterator *iterator =
 413                 NULL;
 414         struct bt_port *port = (void *) self_port;
 415         struct bt_port *upstream_port;
 416         struct bt_component *comp;
 417         struct bt_component *upstream_comp;
 418         struct bt_component_class *upstream_comp_cls;
 419
 420         BT_ASSERT_PRE_NON_NULL(port, "Port");
 421         comp = bt_port_borrow_component_inline(port);
 422         BT_ASSERT_PRE(bt_port_is_connected(port),
 423                 "Port is not connected: %![port-]+p", port);
 424         BT_ASSERT_PRE(comp, "Port is not part of a component: %![port-]+p",
 425                 port);
 426         BT_ASSERT_PRE(!bt_component_graph_is_canceled(comp),
 427                 "Port's component's graph is canceled: "
 428                 "%![port-]+p, %![comp-]+c", port, comp);
 429         BT_ASSERT(port->connection);
 430         upstream_port = port->connection->upstream_port;
 431         BT_ASSERT(upstream_port);
 432         upstream_comp = bt_port_borrow_component_inline(upstream_port);
 433         BT_ASSERT(upstream_comp);
 434         BT_ASSERT_PRE(
 435                 bt_component_borrow_graph(upstream_comp)->config_state !=
 436                         BT_GRAPH_CONFIGURATION_STATE_CONFIGURING,
 437                 "Graph is not configured: %!+g",
 438                 bt_component_borrow_graph(upstream_comp));
 439         upstream_comp_cls = upstream_comp->class;
 440         BT_ASSERT(upstream_comp->class->type ==
 441                 BT_COMPONENT_CLASS_TYPE_SOURCE ||
 442                 upstream_comp->class->type ==
 443                 BT_COMPONENT_CLASS_TYPE_FILTER);
 444         iterator = bt_self_component_port_input_message_iterator_create_initial(
 445                 upstream_comp, upstream_port);
 446         if (!iterator) {
 447                 BT_LOGW_STR("Cannot create self component input port "
 448                         "message iterator.");
 449                 goto end;
 450         }
 451
 452         switch (upstream_comp_cls->type) {
 453         case BT_COMPONENT_CLASS_TYPE_SOURCE:
 454         {
 455                 struct bt_component_class_source *src_comp_cls =
 456                         (void *) upstream_comp_cls;
 457
 458                 init_method =
 459                         (init_method_t) src_comp_cls->methods.msg_iter_init;
 460                 break;
 461         }
 462         case BT_COMPONENT_CLASS_TYPE_FILTER:
 463         {
 464                 struct bt_component_class_filter *flt_comp_cls =
 465                         (void *) upstream_comp_cls;
 466
 467                 init_method =
 468                         (init_method_t) flt_comp_cls->methods.msg_iter_init;
 469                 break;
 470         }
 471         default:
 472                 /* Unreachable */
 473                 abort();
 474         }
 475
 476         if (init_method) {
 477                 int iter_status;
 478
 479                 BT_LIB_LOGD("Calling user's initialization method: %!+i", iterator);
 480                 iter_status = init_method(iterator, upstream_comp,
 481                         upstream_port);
 482                 BT_LOGD("User method returned: status=%s",
 483                         bt_message_iterator_status_string(iter_status));
 484                 if (iter_status != BT_MESSAGE_ITERATOR_STATUS_OK) {
 485                         BT_LOGW_STR("Initialization method failed.");
 486                         BT_OBJECT_PUT_REF_AND_RESET(iterator);
 487                         goto end;
 488                 }
 489         }
 490
 491         set_self_comp_port_input_msg_iterator_state(iterator,
 492                 BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_ACTIVE);
 493         g_ptr_array_add(port->connection->iterators, iterator);
 494         BT_LIB_LOGI("Created message iterator on self component input port: "
 495                 "%![up-port-]+p, %![up-comp-]+c, %![iter-]+i",
 496                 upstream_port, upstream_comp, iterator);
 497
 498 end:
 499         return iterator;
 500 }
 501
 502 void *bt_self_message_iterator_get_data(
 503                 const struct bt_self_message_iterator *self_iterator)
 504 {
 505         struct bt_self_component_port_input_message_iterator *iterator =
 506                 (void *) self_iterator;
 507
 508         BT_ASSERT_PRE_NON_NULL(iterator, "Message iterator");
 509         return iterator->user_data;
 510 }
 511
 512 void bt_self_message_iterator_set_data(
 513                 struct bt_self_message_iterator *self_iterator, void *data)
 514 {
 515         struct bt_self_component_port_input_message_iterator *iterator =
 516                 (void *) self_iterator;
 517
 518         BT_ASSERT_PRE_NON_NULL(iterator, "Message iterator");
 519         iterator->user_data = data;
 520         BT_LIB_LOGD("Set message iterator's user data: "
 521                 "%!+i, user-data-addr=%p", iterator, data);
 522 }
 523
 524 enum bt_message_iterator_status
 525 bt_self_component_port_input_message_iterator_next(
 526                 struct bt_self_component_port_input_message_iterator *iterator,
 527                 bt_message_array_const *msgs, uint64_t *user_count)
 528 {
 529         int status = BT_MESSAGE_ITERATOR_STATUS_OK;
 530
 531         BT_ASSERT_PRE_NON_NULL(iterator, "Message iterator");
 532         BT_ASSERT_PRE_NON_NULL(msgs, "Message array (output)");
 533         BT_ASSERT_PRE_NON_NULL(user_count, "Message count (output)");
 534         BT_ASSERT_PRE(iterator->state ==
 535                 BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_ACTIVE,
 536                 "Message iterator's \"next\" called, but "
 537                 "message iterator is in the wrong state: %!+i", iterator);
 538         BT_ASSERT(iterator->upstream_component);
 539         BT_ASSERT(iterator->upstream_component->class);
 540         BT_ASSERT_PRE(
 541                 bt_component_borrow_graph(iterator->upstream_component)->config_state !=
 542                         BT_GRAPH_CONFIGURATION_STATE_CONFIGURING,
 543                 "Graph is not configured: %!+g",
 544                 bt_component_borrow_graph(iterator->upstream_component));
 545         BT_LIB_LOGD("Getting next self component input port "
 546                 "message iterator's messages: %!+i, batch-size=%u",
 547                 iterator, MSG_BATCH_SIZE);
 548
 549         /*
 550          * Call the user's "next" method to get the next messages
 551          * and status.
 552          */
 553         BT_ASSERT(iterator->methods.next);
 554         BT_LOGD_STR("Calling user's \"next\" method.");
 555         *user_count = 0;
 556         status = iterator->methods.next(iterator,
 557                 (void *) iterator->base.msgs->pdata, MSG_BATCH_SIZE,
 558                 user_count);
 559         BT_LOGD("User method returned: status=%s, msg-count=%" PRIu64,
 560                 bt_message_iterator_status_string(status), *user_count);
 561         if (status < 0) {
 562                 BT_LOGW_STR("User method failed.");
 563                 goto end;
 564         }
 565
 566         /*
 567          * There is no way that this iterator could have been finalized
 568          * during its "next" method, as the only way to do this is to
 569          * put the last iterator's reference, and this can only be done
 570          * by its downstream owner.
 571          *
 572          * For the same reason, there is no way that this iterator could
 573          * have seeked (cannot seek a self message iterator).
 574          */
 575         BT_ASSERT(iterator->state ==
 576                 BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_ACTIVE);
 577
 578         switch (status) {
 579         case BT_MESSAGE_ITERATOR_STATUS_OK:
 580                 BT_ASSERT_PRE(*user_count <= MSG_BATCH_SIZE,
 581                         "Invalid returned message count: greater than "
 582                         "batch size: count=%" PRIu64 ", batch-size=%u",
 583                         *user_count, MSG_BATCH_SIZE);
 584                 *msgs = (void *) iterator->base.msgs->pdata;
 585                 break;
 586         case BT_MESSAGE_ITERATOR_STATUS_AGAIN:
 587                 goto end;
 588         case BT_MESSAGE_ITERATOR_STATUS_END:
 589                 set_self_comp_port_input_msg_iterator_state(iterator,
 590                         BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_ENDED);
 591                 goto end;
 592         default:
 593                 /* Unknown non-error status */
 594                 abort();
 595         }
 596
 597 end:
 598         return status;
 599 }
 600
 601 enum bt_message_iterator_status bt_port_output_message_iterator_next(
 602                 struct bt_port_output_message_iterator *iterator,
 603                 bt_message_array_const *msgs_to_user,
 604                 uint64_t *count_to_user)
 605 {
 606         enum bt_message_iterator_status status;
 607         enum bt_graph_status graph_status;
 608
 609         BT_ASSERT_PRE_NON_NULL(iterator, "Message iterator");
 610         BT_ASSERT_PRE_NON_NULL(msgs_to_user, "Message array (output)");
 611         BT_ASSERT_PRE_NON_NULL(count_to_user, "Message count (output)");
 612         BT_LIB_LOGD("Getting next output port message iterator's messages: "
 613                 "%!+i", iterator);
 614         graph_status = bt_graph_consume_sink_no_check(iterator->graph,
 615                 iterator->colander);
 616         switch (graph_status) {
 617         case BT_GRAPH_STATUS_CANCELED:
 618         case BT_GRAPH_STATUS_AGAIN:
 619         case BT_GRAPH_STATUS_END:
 620         case BT_GRAPH_STATUS_NOMEM:
 621                 status = (int) graph_status;
 622                 break;
 623         case BT_GRAPH_STATUS_OK:
 624                 status = BT_MESSAGE_ITERATOR_STATUS_OK;
 625
 626                 /*
 627                  * On success, the colander sink moves the messages
 628                  * to this iterator's array and sets this iterator's
 629                  * message count: move them to the user.
 630                  */
 631                 *msgs_to_user = (void *) iterator->base.msgs->pdata;
 632                 *count_to_user = iterator->count;
 633                 break;
 634         default:
 635                 /* Other errors */
 636                 status = BT_MESSAGE_ITERATOR_STATUS_ERROR;
 637         }
 638
 639         return status;
 640 }
 641
 642 struct bt_component *
 643 bt_self_component_port_input_message_iterator_borrow_component(
 644                 struct bt_self_component_port_input_message_iterator *iterator)
 645 {
 646         BT_ASSERT_PRE_NON_NULL(iterator, "Message iterator");
 647         return iterator->upstream_component;
 648 }
 649
 650 const struct bt_component *
 651 bt_self_component_port_input_message_iterator_borrow_component_const(
 652                 const struct bt_self_component_port_input_message_iterator *iterator)
 653 {
 654         BT_ASSERT_PRE_NON_NULL(iterator, "Message iterator");
 655         return iterator->upstream_component;
 656 }
 657
 658 struct bt_self_component *bt_self_message_iterator_borrow_component(
 659                 struct bt_self_message_iterator *self_iterator)
 660 {
 661         struct bt_self_component_port_input_message_iterator *iterator =
 662                 (void *) self_iterator;
 663
 664         BT_ASSERT_PRE_NON_NULL(iterator, "Message iterator");
 665         return (void *) iterator->upstream_component;
 666 }
 667
 668 struct bt_self_port_output *bt_self_message_iterator_borrow_port(
 669                 struct bt_self_message_iterator *self_iterator)
 670 {
 671         struct bt_self_component_port_input_message_iterator *iterator =
 672                 (void *) self_iterator;
 673
 674         BT_ASSERT_PRE_NON_NULL(iterator, "Message iterator");
 675         return (void *) iterator->upstream_port;
 676 }
 677
 678 static
 679 void bt_port_output_message_iterator_destroy(struct bt_object *obj)
 680 {
 681         struct bt_port_output_message_iterator *iterator = (void *) obj;
 682
 683         BT_LIB_LOGI("Destroying output port message iterator object: %!+i",
 684                 iterator);
 685         BT_LOGD_STR("Putting graph.");
 686         BT_OBJECT_PUT_REF_AND_RESET(iterator->graph);
 687         BT_LOGD_STR("Putting colander sink component.");
 688         BT_OBJECT_PUT_REF_AND_RESET(iterator->colander);
 689         destroy_base_message_iterator(obj);
 690 }
 691
 692 struct bt_port_output_message_iterator *
 693 bt_port_output_message_iterator_create(struct bt_graph *graph,
 694                 const struct bt_port_output *output_port)
 695 {
 696         struct bt_port_output_message_iterator *iterator = NULL;
 697         struct bt_component_class_sink *colander_comp_cls = NULL;
 698         struct bt_component *output_port_comp = NULL;
 699         struct bt_component_sink *colander_comp;
 700         enum bt_graph_status graph_status;
 701         struct bt_port_input *colander_in_port = NULL;
 702         struct bt_component_class_sink_colander_data colander_data;
 703         int ret;
 704
 705         BT_ASSERT_PRE_NON_NULL(graph, "Graph");
 706         BT_ASSERT_PRE_NON_NULL(output_port, "Output port");
 707         output_port_comp = bt_port_borrow_component_inline(
 708                 (const void *) output_port);
 709         BT_ASSERT_PRE(output_port_comp,
 710                 "Output port has no component: %!+p", output_port);
 711         BT_ASSERT_PRE(bt_component_borrow_graph(output_port_comp) ==
 712                 (void *) graph,
 713                 "Output port is not part of graph: %![graph-]+g, %![port-]+p",
 714                 graph, output_port);
 715         BT_ASSERT_PRE(!graph->has_sink,
 716                 "Graph already has a sink component: %![graph-]+g");
 717
 718         /* Create message iterator */
 719         BT_LIB_LOGI("Creating message iterator on output port: "
 720                 "%![port-]+p, %![comp-]+c", output_port, output_port_comp);
 721         iterator = g_new0(struct bt_port_output_message_iterator, 1);
 722         if (!iterator) {
 723                 BT_LOGE_STR("Failed to allocate one output port message iterator.");
 724                 goto error;
 725         }
 726
 727         ret = init_message_iterator((void *) iterator,
 728                 BT_MESSAGE_ITERATOR_TYPE_PORT_OUTPUT,
 729                 bt_port_output_message_iterator_destroy);
 730         if (ret) {
 731                 /* init_message_iterator() logs errors */
 732                 BT_OBJECT_PUT_REF_AND_RESET(iterator);
 733                 goto end;
 734         }
 735
 736         /* Create colander component */
 737         colander_comp_cls = bt_component_class_sink_colander_get();
 738         if (!colander_comp_cls) {
 739                 BT_LOGW("Cannot get colander sink component class.");
 740                 goto error;
 741         }
 742
 743         iterator->graph = graph;
 744         bt_object_get_no_null_check(iterator->graph);
 745         colander_data.msgs = (void *) iterator->base.msgs->pdata;
 746         colander_data.count_addr = &iterator->count;
 747
 748         /* Hope that nobody uses this very unique name */
 749         graph_status =
 750                 bt_graph_add_sink_component_with_init_method_data(
 751                         (void *) graph, colander_comp_cls,
 752                         "colander-36ac3409-b1a8-4d60-ab1f-4fdf341a8fb1",
 753                         NULL, &colander_data, (void *) &iterator->colander);
 754         if (graph_status != BT_GRAPH_STATUS_OK) {
 755                 BT_LIB_LOGW("Cannot add colander sink component to graph: "
 756                         "%1[graph-]+g, status=%s", graph,
 757                         bt_graph_status_string(graph_status));
 758                 goto error;
 759         }
 760
 761         /*
 762          * Connect provided output port to the colander component's
 763          * input port.
 764          */
 765         colander_in_port =
 766                 (void *) bt_component_sink_borrow_input_port_by_index_const(
 767                         (void *) iterator->colander, 0);
 768         BT_ASSERT(colander_in_port);
 769         graph_status = bt_graph_connect_ports(graph,
 770                 output_port, colander_in_port, NULL);
 771         if (graph_status != BT_GRAPH_STATUS_OK) {
 772                 BT_LIB_LOGW("Cannot add colander sink component to graph: "
 773                         "%![graph-]+g, %![comp-]+c, status=%s", graph,
 774                         iterator->colander,
 775                         bt_graph_status_string(graph_status));
 776                 goto error;
 777         }
 778
 779         /*
 780          * At this point everything went fine. Make the graph
 781          * nonconsumable forever so that only this message iterator
 782          * can consume (thanks to bt_graph_consume_sink_no_check()).
 783          * This avoids leaking the message created by the colander
 784          * sink and moved to the message iterator's message
 785          * member.
 786          */
 787         bt_graph_set_can_consume(iterator->graph, false);
 788
 789         /* Also set the graph as being configured. */
 790         graph_status = bt_graph_configure(graph);
 791         if (graph_status != BT_GRAPH_STATUS_OK) {
 792                 BT_LIB_LOGW("Cannot configure graph after having added colander: "
 793                         "%![graph-]+g, status=%s", graph,
 794                         bt_graph_status_string(graph_status));
 795                 goto error;
 796         }
 797         goto end;
 798
 799 error:
 800         if (iterator && iterator->graph && iterator->colander) {
 801                 int ret;
 802
 803                 /* Remove created colander component from graph if any */
 804                 colander_comp = iterator->colander;
 805                 BT_OBJECT_PUT_REF_AND_RESET(iterator->colander);
 806
 807                 /*
 808                  * At this point the colander component's reference
 809                  * count is 0 because iterator->colander was the only
 810                  * owner. We also know that it is not connected because
 811                  * this is the last operation before this function
 812                  * succeeds.
 813                  *
 814                  * Since we honor the preconditions here,
 815                  * bt_graph_remove_unconnected_component() always
 816                  * succeeds.
 817                  */
 818                 ret = bt_graph_remove_unconnected_component(iterator->graph,
 819                         (void *) colander_comp);
 820                 BT_ASSERT(ret == 0);
 821         }
 822
 823         BT_OBJECT_PUT_REF_AND_RESET(iterator);
 824
 825 end:
 826         bt_object_put_ref(colander_comp_cls);
 827         return (void *) iterator;
 828 }
 829
 830 bt_bool bt_self_component_port_input_message_iterator_can_seek_ns_from_origin(
 831                 struct bt_self_component_port_input_message_iterator *iterator,
 832                 int64_t ns_from_origin)
 833 {
 834         bt_bool can = BT_FALSE;
 835
 836         BT_ASSERT_PRE_NON_NULL(iterator, "Message iterator");
 837         BT_ASSERT_PRE_ITER_HAS_STATE_TO_SEEK(iterator);
 838         BT_ASSERT_PRE(
 839                 bt_component_borrow_graph(iterator->upstream_component)->config_state !=
 840                         BT_GRAPH_CONFIGURATION_STATE_CONFIGURING,
 841                 "Graph is not configured: %!+g",
 842                 bt_component_borrow_graph(iterator->upstream_component));
 843
 844         if (iterator->methods.can_seek_ns_from_origin) {
 845                 can = iterator->methods.can_seek_ns_from_origin(iterator,
 846                         ns_from_origin);
 847                 goto end;
 848         }
 849
 850         /*
 851          * Automatic seeking fall back: if we can seek to the beginning,
 852          * then we can automatically seek to any message.
 853          */
 854         if (iterator->methods.can_seek_beginning) {
 855                 can = iterator->methods.can_seek_beginning(iterator);
 856         }
 857
 858 end:
 859         return can;
 860 }
 861
 862 bt_bool bt_self_component_port_input_message_iterator_can_seek_beginning(
 863                 struct bt_self_component_port_input_message_iterator *iterator)
 864 {
 865         bt_bool can = BT_FALSE;
 866
 867         BT_ASSERT_PRE_NON_NULL(iterator, "Message iterator");
 868         BT_ASSERT_PRE_ITER_HAS_STATE_TO_SEEK(iterator);
 869         BT_ASSERT_PRE(
 870                 bt_component_borrow_graph(iterator->upstream_component)->config_state !=
 871                         BT_GRAPH_CONFIGURATION_STATE_CONFIGURING,
 872                 "Graph is not configured: %!+g",
 873                 bt_component_borrow_graph(iterator->upstream_component));
 874
 875         if (iterator->methods.can_seek_beginning) {
 876                 can = iterator->methods.can_seek_beginning(iterator);
 877         }
 878
 879         return can;
 880 }
 881
 882 static inline
 883 void set_iterator_state_after_seeking(
 884                 struct bt_self_component_port_input_message_iterator *iterator,
 885                 enum bt_message_iterator_status status)
 886 {
 887         enum bt_self_component_port_input_message_iterator_state new_state = 0;
 888
 889         /* Set iterator's state depending on seeking status */
 890         switch (status) {
 891         case BT_MESSAGE_ITERATOR_STATUS_OK:
 892                 new_state = BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_ACTIVE;
 893                 break;
 894         case BT_MESSAGE_ITERATOR_STATUS_AGAIN:
 895                 new_state = BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_LAST_SEEKING_RETURNED_AGAIN;
 896                 break;
 897         case BT_MESSAGE_ITERATOR_STATUS_ERROR:
 898         case BT_MESSAGE_ITERATOR_STATUS_NOMEM:
 899                 new_state = BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_LAST_SEEKING_RETURNED_ERROR;
 900                 break;
 901         case BT_MESSAGE_ITERATOR_STATUS_END:
 902                 new_state = BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_ENDED;
 903                 break;
 904         default:
 905                 abort();
 906         }
 907
 908         set_self_comp_port_input_msg_iterator_state(iterator, new_state);
 909 }
 910
 911 enum bt_message_iterator_status
 912 bt_self_component_port_input_message_iterator_seek_beginning(
 913                 struct bt_self_component_port_input_message_iterator *iterator)
 914 {
 915         int status;
 916
 917         BT_ASSERT_PRE_NON_NULL(iterator, "Message iterator");
 918         BT_ASSERT_PRE_ITER_HAS_STATE_TO_SEEK(iterator);
 919         BT_ASSERT_PRE(
 920                 bt_component_borrow_graph(iterator->upstream_component)->config_state !=
 921                         BT_GRAPH_CONFIGURATION_STATE_CONFIGURING,
 922                 "Graph is not configured: %!+g",
 923                 bt_component_borrow_graph(iterator->upstream_component));
 924         BT_ASSERT_PRE(
 925                 bt_self_component_port_input_message_iterator_can_seek_beginning(
 926                         iterator),
 927                 "Message iterator cannot seek beginning: %!+i", iterator);
 928         BT_LIB_LOGD("Calling user's \"seek beginning\" method: %!+i", iterator);
 929         set_self_comp_port_input_msg_iterator_state(iterator,
 930                 BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_SEEKING);
 931         status = iterator->methods.seek_beginning(iterator);
 932         BT_LOGD("User method returned: status=%s",
 933                 bt_message_iterator_status_string(status));
 934         BT_ASSERT_PRE(status == BT_MESSAGE_ITERATOR_STATUS_OK ||
 935                 status == BT_MESSAGE_ITERATOR_STATUS_ERROR ||
 936                 status == BT_MESSAGE_ITERATOR_STATUS_NOMEM ||
 937                 status == BT_MESSAGE_ITERATOR_STATUS_AGAIN,
 938                 "Unexpected status: %![iter-]+i, status=%s",
 939                 iterator, bt_common_self_message_iterator_status_string(status));
 940         set_iterator_state_after_seeking(iterator, status);
 941         return status;
 942 }
 943
 944 static inline
 945 enum bt_message_iterator_status auto_seek_handle_message(
 946                 struct bt_self_component_port_input_message_iterator *iterator,
 947                 int64_t ns_from_origin, const struct bt_message *msg,
 948                 bool *got_first)
 949 {
 950         enum bt_message_iterator_status status = BT_MESSAGE_ITERATOR_STATUS_OK;
 951         int64_t msg_ns_from_origin;
 952         const struct bt_clock_snapshot *clk_snapshot = NULL;
 953         int ret;
 954
 955         BT_ASSERT(msg);
 956         BT_ASSERT(got_first);
 957
 958         switch (msg->type) {
 959         case BT_MESSAGE_TYPE_EVENT:
 960         {
 961                 const struct bt_message_event *event_msg =
 962                         (const void *) msg;
 963
 964                 clk_snapshot = event_msg->default_cs;
 965                 BT_ASSERT_PRE(clk_snapshot,
 966                         "Event message has no default clock snapshot: %!+n",
 967                         event_msg);
 968                 break;
 969         }
 970         case BT_MESSAGE_TYPE_MESSAGE_ITERATOR_INACTIVITY:
 971         {
 972                 const struct bt_message_message_iterator_inactivity *inactivity_msg =
 973                         (const void *) msg;
 974
 975                 clk_snapshot = inactivity_msg->default_cs;
 976                 BT_ASSERT(clk_snapshot);
 977                 break;
 978         }
 979         case BT_MESSAGE_TYPE_PACKET_BEGINNING:
 980         case BT_MESSAGE_TYPE_PACKET_END:
 981         {
 982                 const struct bt_message_packet *packet_msg =
 983                         (const void *) msg;
 984
 985                 clk_snapshot = packet_msg->default_cs;
 986                 BT_ASSERT_PRE(clk_snapshot,
 987                         "Packet message has no default clock snapshot: %!+n",
 988                         packet_msg);
 989                 break;
 990         }
 991         case BT_MESSAGE_TYPE_DISCARDED_EVENTS:
 992         case BT_MESSAGE_TYPE_DISCARDED_PACKETS:
 993         {
 994                 struct bt_message_discarded_items *msg_disc_items =
 995                         (void *) msg;
 996
 997                 BT_ASSERT_PRE(msg_disc_items->default_begin_cs &&
 998                         msg_disc_items->default_end_cs,
 999                         "Discarded events/packets message has no default clock snapshots: %!+n",
1000                         msg_disc_items);
1001                 ret = bt_clock_snapshot_get_ns_from_origin(
1002                         msg_disc_items->default_begin_cs,
1003                         &msg_ns_from_origin);
1004                 if (ret) {
1005                         status = BT_MESSAGE_ITERATOR_STATUS_ERROR;
1006                         goto end;
1007                 }
1008
1009                 if (msg_ns_from_origin >= ns_from_origin) {
1010                         *got_first = true;
1011                         goto push_msg;
1012                 }
1013
1014                 ret = bt_clock_snapshot_get_ns_from_origin(
1015                         msg_disc_items->default_end_cs,
1016                         &msg_ns_from_origin);
1017                 if (ret) {
1018                         status = BT_MESSAGE_ITERATOR_STATUS_ERROR;
1019                         goto end;
1020                 }
1021
1022                 if (msg_ns_from_origin >= ns_from_origin) {
1023                         /*
1024                          * The discarded items message's beginning time
1025                          * is before the requested seeking time, but its
1026                          * end time is after. Modify the message so as
1027                          * to set its beginning time to the requested
1028                          * seeking time, and make its item count unknown
1029                          * as we don't know if items were really
1030                          * discarded within the new time range.
1031                          */
1032                         uint64_t new_begin_raw_value;
1033
1034                         ret = bt_clock_class_clock_value_from_ns_from_origin(
1035                                 msg_disc_items->default_end_cs->clock_class,
1036                                 ns_from_origin, &new_begin_raw_value);
1037                         if (ret) {
1038                                 status = BT_MESSAGE_ITERATOR_STATUS_ERROR;
1039                                 goto end;
1040                         }
1041
1042                         bt_clock_snapshot_set_raw_value(
1043                                 msg_disc_items->default_begin_cs,
1044                                 new_begin_raw_value);
1045                         msg_disc_items->count.base.avail =
1046                                 BT_PROPERTY_AVAILABILITY_NOT_AVAILABLE;
1047
1048                         /*
1049                          * It is safe to push it because its beginning
1050                          * time is exactly the requested seeking time.
1051                          */
1052                         goto push_msg;
1053                 } else {
1054                         goto skip_msg;
1055                 }
1056         }
1057         case BT_MESSAGE_TYPE_STREAM_ACTIVITY_BEGINNING:
1058         {
1059                 const struct bt_message_stream_activity *stream_act_msg =
1060                         (const void *) msg;
1061
1062                 switch (stream_act_msg->default_cs_state) {
1063                 case BT_MESSAGE_STREAM_ACTIVITY_CLOCK_SNAPSHOT_STATE_UNKNOWN:
1064                 case BT_MESSAGE_STREAM_ACTIVITY_CLOCK_SNAPSHOT_STATE_INFINITE:
1065                         /*
1066                          * -inf is always less than any requested time,
1067                          * and we can't assume any specific time for an
1068                          * unknown clock snapshot, so skip this.
1069                          */
1070                         goto skip_msg;
1071                 case BT_MESSAGE_STREAM_ACTIVITY_CLOCK_SNAPSHOT_STATE_KNOWN:
1072                         clk_snapshot = stream_act_msg->default_cs;
1073                         BT_ASSERT(clk_snapshot);
1074                         break;
1075                 default:
1076                         abort();
1077                 }
1078
1079                 break;
1080         }
1081         case BT_MESSAGE_TYPE_STREAM_ACTIVITY_END:
1082         {
1083                 const struct bt_message_stream_activity *stream_act_msg =
1084                         (const void *) msg;
1085
1086                 switch (stream_act_msg->default_cs_state) {
1087                 case BT_MESSAGE_STREAM_ACTIVITY_CLOCK_SNAPSHOT_STATE_UNKNOWN:
1088                         /*
1089                          * We can't assume any specific time for an
1090                          * unknown clock snapshot, so skip this.
1091                          */
1092                         goto skip_msg;
1093                 case BT_MESSAGE_STREAM_ACTIVITY_CLOCK_SNAPSHOT_STATE_INFINITE:
1094                         /*
1095                          * +inf is always greater than any requested
1096                          * time.
1097                          */
1098                         *got_first = true;
1099                         goto push_msg;
1100                 case BT_MESSAGE_STREAM_ACTIVITY_CLOCK_SNAPSHOT_STATE_KNOWN:
1101                         clk_snapshot = stream_act_msg->default_cs;
1102                         BT_ASSERT(clk_snapshot);
1103                         break;
1104                 default:
1105                         abort();
1106                 }
1107
1108                 break;
1109         }
1110         case BT_MESSAGE_TYPE_STREAM_BEGINNING:
1111         case BT_MESSAGE_TYPE_STREAM_END:
1112                 /* Ignore */
1113                 goto skip_msg;
1114         default:
1115                 abort();
1116         }
1117
1118         BT_ASSERT(clk_snapshot);
1119         ret = bt_clock_snapshot_get_ns_from_origin(clk_snapshot,
1120                 &msg_ns_from_origin);
1121         if (ret) {
1122                 status = BT_MESSAGE_ITERATOR_STATUS_ERROR;
1123                 goto end;
1124         }
1125
1126         if (msg_ns_from_origin >= ns_from_origin) {
1127                 *got_first = true;
1128                 goto push_msg;
1129         }
1130
1131 skip_msg:
1132         bt_object_put_no_null_check(msg);
1133         msg = NULL;
1134         goto end;
1135
1136 push_msg:
1137         g_queue_push_head(iterator->auto_seek_msgs, (void *) msg);
1138         msg = NULL;
1139
1140 end:
1141         BT_ASSERT(!msg || status != BT_MESSAGE_ITERATOR_STATUS_OK);
1142         return status;
1143 }
1144
1145 static
1146 enum bt_message_iterator_status find_message_ge_ns_from_origin(
1147                 struct bt_self_component_port_input_message_iterator *iterator,
1148                 int64_t ns_from_origin)
1149 {
1150         int status;
1151         enum bt_self_component_port_input_message_iterator_state init_state =
1152                 iterator->state;
1153         const struct bt_message *messages[MSG_BATCH_SIZE];
1154         uint64_t user_count = 0;
1155         uint64_t i;
1156         bool got_first = false;
1157
1158         BT_ASSERT(iterator);
1159         memset(&messages[0], 0, sizeof(messages[0]) * MSG_BATCH_SIZE);
1160
1161         /*
1162          * Make this iterator temporarily active (not seeking) to call
1163          * the "next" method.
1164          */
1165         set_self_comp_port_input_msg_iterator_state(iterator,
1166                 BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_ACTIVE);
1167
1168         BT_ASSERT(iterator->methods.next);
1169
1170         while (!got_first) {
1171                 /*
1172                  * Call the user's "next" method to get the next
1173                  * messages and status.
1174                  */
1175                 BT_LOGD_STR("Calling user's \"next\" method.");
1176                 status = iterator->methods.next(iterator,
1177                         &messages[0], MSG_BATCH_SIZE, &user_count);
1178                 BT_LOGD("User method returned: status=%s",
1179                         bt_message_iterator_status_string(status));
1180
1181                 /*
1182                  * The user's "next" method must not do any action which
1183                  * would change the iterator's state.
1184                  */
1185                 BT_ASSERT(iterator->state ==
1186                         BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_ACTIVE);
1187
1188                 switch (status) {
1189                 case BT_MESSAGE_ITERATOR_STATUS_OK:
1190                         BT_ASSERT_PRE(user_count <= MSG_BATCH_SIZE,
1191                                 "Invalid returned message count: greater than "
1192                                 "batch size: count=%" PRIu64 ", batch-size=%u",
1193                                 user_count, MSG_BATCH_SIZE);
1194                         break;
1195                 case BT_MESSAGE_ITERATOR_STATUS_AGAIN:
1196                 case BT_MESSAGE_ITERATOR_STATUS_ERROR:
1197                 case BT_MESSAGE_ITERATOR_STATUS_NOMEM:
1198                 case BT_MESSAGE_ITERATOR_STATUS_END:
1199                         goto end;
1200                 default:
1201                         abort();
1202                 }
1203
1204                 for (i = 0; i < user_count; i++) {
1205                         if (got_first) {
1206                                 g_queue_push_head(iterator->auto_seek_msgs,
1207                                         (void *) messages[i]);
1208                                 messages[i] = NULL;
1209                                 continue;
1210                         }
1211
1212                         status = auto_seek_handle_message(iterator,
1213                                 ns_from_origin, messages[i], &got_first);
1214                         if (status == BT_MESSAGE_ITERATOR_STATUS_OK) {
1215                                 /* Message was either pushed or moved */
1216                                 messages[i] = NULL;
1217                         } else {
1218                                 goto end;
1219                         }
1220                 }
1221         }
1222
1223 end:
1224         for (i = 0; i < user_count; i++) {
1225                 if (messages[i]) {
1226                         bt_object_put_no_null_check(messages[i]);
1227                 }
1228         }
1229
1230         set_self_comp_port_input_msg_iterator_state(iterator, init_state);
1231         return status;
1232 }
1233
1234 static
1235 enum bt_self_message_iterator_status post_auto_seek_next(
1236                 struct bt_self_component_port_input_message_iterator *iterator,
1237                 bt_message_array_const msgs, uint64_t capacity,
1238                 uint64_t *count)
1239 {
1240         BT_ASSERT(!g_queue_is_empty(iterator->auto_seek_msgs));
1241         *count = 0;
1242
1243         /*
1244          * Move auto-seek messages to the output array (which is this
1245          * iterator's base message array).
1246          */
1247         while (capacity > 0 && !g_queue_is_empty(iterator->auto_seek_msgs)) {
1248                 msgs[*count] = g_queue_pop_tail(iterator->auto_seek_msgs);
1249                 capacity--;
1250                 (*count)++;
1251         }
1252
1253         BT_ASSERT(*count > 0);
1254
1255         if (g_queue_is_empty(iterator->auto_seek_msgs)) {
1256                 /* No more auto-seek messages */
1257                 switch (iterator->upstream_component->class->type) {
1258                 case BT_COMPONENT_CLASS_TYPE_SOURCE:
1259                 {
1260                         struct bt_component_class_source *src_comp_cls =
1261                                 (void *) iterator->upstream_component->class;
1262
1263                         iterator->methods.next =
1264                                 (bt_self_component_port_input_message_iterator_next_method)
1265                                         src_comp_cls->methods.msg_iter_next;
1266                         break;
1267                 }
1268                 case BT_COMPONENT_CLASS_TYPE_FILTER:
1269                 {
1270                         struct bt_component_class_filter *flt_comp_cls =
1271                                 (void *) iterator->upstream_component->class;
1272
1273                         iterator->methods.next =
1274                                 (bt_self_component_port_input_message_iterator_next_method)
1275                                         flt_comp_cls->methods.msg_iter_next;
1276                         break;
1277                 }
1278                 default:
1279                         abort();
1280                 }
1281         }
1282
1283         return BT_SELF_MESSAGE_ITERATOR_STATUS_OK;
1284 }
1285
1286 enum bt_message_iterator_status
1287 bt_self_component_port_input_message_iterator_seek_ns_from_origin(
1288                 struct bt_self_component_port_input_message_iterator *iterator,
1289                 int64_t ns_from_origin)
1290 {
1291         int status;
1292
1293         BT_ASSERT_PRE_NON_NULL(iterator, "Message iterator");
1294         BT_ASSERT_PRE_ITER_HAS_STATE_TO_SEEK(iterator);
1295         BT_ASSERT_PRE(
1296                 bt_component_borrow_graph(iterator->upstream_component)->config_state !=
1297                         BT_GRAPH_CONFIGURATION_STATE_CONFIGURING,
1298                 "Graph is not configured: %!+g",
1299                 bt_component_borrow_graph(iterator->upstream_component));
1300         BT_ASSERT_PRE(
1301                 bt_self_component_port_input_message_iterator_can_seek_ns_from_origin(
1302                         iterator, ns_from_origin),
1303                 "Message iterator cannot seek nanoseconds from origin: %!+i, "
1304                 "ns-from-origin=%" PRId64, iterator, ns_from_origin);
1305         set_self_comp_port_input_msg_iterator_state(iterator,
1306                 BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_STATE_SEEKING);
1307
1308         if (iterator->methods.seek_ns_from_origin) {
1309                 BT_LIB_LOGD("Calling user's \"seek nanoseconds from origin\" method: "
1310                         "%![iter-]+i, ns=%" PRId64, iterator, ns_from_origin);
1311                 status = iterator->methods.seek_ns_from_origin(iterator,
1312                         ns_from_origin);
1313                 BT_LOGD("User method returned: status=%s",
1314                         bt_message_iterator_status_string(status));
1315                 BT_ASSERT_PRE(status == BT_MESSAGE_ITERATOR_STATUS_OK ||
1316                         status == BT_MESSAGE_ITERATOR_STATUS_ERROR ||
1317                         status == BT_MESSAGE_ITERATOR_STATUS_NOMEM ||
1318                         status == BT_MESSAGE_ITERATOR_STATUS_AGAIN,
1319                         "Unexpected status: %![iter-]+i, status=%s",
1320                         iterator,
1321                         bt_common_self_message_iterator_status_string(status));
1322         } else {
1323                 /* Start automatic seeking: seek beginning first */
1324                 BT_ASSERT(iterator->methods.can_seek_beginning(iterator));
1325                 BT_ASSERT(iterator->methods.seek_beginning);
1326                 BT_LIB_LOGD("Calling user's \"seek beginning\" method: %!+i",
1327                         iterator);
1328                 status = iterator->methods.seek_beginning(iterator);
1329                 BT_LOGD("User method returned: status=%s",
1330                         bt_message_iterator_status_string(status));
1331                 BT_ASSERT_PRE(status == BT_MESSAGE_ITERATOR_STATUS_OK ||
1332                         status == BT_MESSAGE_ITERATOR_STATUS_ERROR ||
1333                         status == BT_MESSAGE_ITERATOR_STATUS_NOMEM ||
1334                         status == BT_MESSAGE_ITERATOR_STATUS_AGAIN,
1335                         "Unexpected status: %![iter-]+i, status=%s",
1336                         iterator,
1337                         bt_common_self_message_iterator_status_string(status));
1338                 switch (status) {
1339                 case BT_MESSAGE_ITERATOR_STATUS_OK:
1340                         break;
1341                 case BT_MESSAGE_ITERATOR_STATUS_ERROR:
1342                 case BT_MESSAGE_ITERATOR_STATUS_NOMEM:
1343                 case BT_MESSAGE_ITERATOR_STATUS_AGAIN:
1344                         goto end;
1345                 default:
1346                         abort();
1347                 }
1348
1349                 /*
1350                  * Find the first message which has a default clock
1351                  * snapshot greater than or equal to the requested
1352                  * seeking time, and move the received messages from
1353                  * this point in the batch to this iterator's auto-seek
1354                  * message queue.
1355                  */
1356                 while (!g_queue_is_empty(iterator->auto_seek_msgs)) {
1357                         bt_object_put_no_null_check(
1358                                 g_queue_pop_tail(iterator->auto_seek_msgs));
1359                 }
1360
1361                 status = find_message_ge_ns_from_origin(iterator,
1362                         ns_from_origin);
1363                 switch (status) {
1364                 case BT_MESSAGE_ITERATOR_STATUS_OK:
1365                 case BT_MESSAGE_ITERATOR_STATUS_END:
1366                         /*
1367                          * If there are messages in the auto-seek
1368                          * message queue, replace the user's "next"
1369                          * method with a custom, temporary "next" method
1370                          * which returns them.
1371                          */
1372                         if (!g_queue_is_empty(iterator->auto_seek_msgs)) {
1373                                 iterator->methods.next =
1374                                         (bt_self_component_port_input_message_iterator_next_method)
1375                                                 post_auto_seek_next;
1376                         }
1377
1378                         /*
1379                          * `BT_MESSAGE_ITERATOR_STATUS_END` becomes
1380                          * `BT_MESSAGE_ITERATOR_STATUS_OK`: the next
1381                          * time this iterator's "next" method is called,
1382                          * it will return
1383                          * `BT_MESSAGE_ITERATOR_STATUS_END`.
1384                          */
1385                         status = BT_MESSAGE_ITERATOR_STATUS_OK;
1386                         break;
1387                 case BT_MESSAGE_ITERATOR_STATUS_ERROR:
1388                 case BT_MESSAGE_ITERATOR_STATUS_NOMEM:
1389                 case BT_MESSAGE_ITERATOR_STATUS_AGAIN:
1390                         goto end;
1391                 default:
1392                         abort();
1393                 }
1394         }
1395
1396 end:
1397         set_iterator_state_after_seeking(iterator, status);
1398         return status;
1399 }
1400
1401 static inline
1402 bt_self_component_port_input_message_iterator *
1403 borrow_output_port_message_iterator_upstream_iterator(
1404                 struct bt_port_output_message_iterator *iterator)
1405 {
1406         struct bt_component_class_sink_colander_priv_data *colander_data;
1407
1408         BT_ASSERT(iterator);
1409         colander_data = (void *) iterator->colander->parent.user_data;
1410         BT_ASSERT(colander_data);
1411         BT_ASSERT(colander_data->msg_iter);
1412         return colander_data->msg_iter;
1413 }
1414
1415 bt_bool bt_port_output_message_iterator_can_seek_ns_from_origin(
1416                 struct bt_port_output_message_iterator *iterator,
1417                 int64_t ns_from_origin)
1418 {
1419         BT_ASSERT_PRE_NON_NULL(iterator, "Message iterator");
1420         return bt_self_component_port_input_message_iterator_can_seek_ns_from_origin(
1421                 borrow_output_port_message_iterator_upstream_iterator(
1422                         iterator), ns_from_origin);
1423 }
1424
1425 bt_bool bt_port_output_message_iterator_can_seek_beginning(
1426                 struct bt_port_output_message_iterator *iterator)
1427 {
1428         BT_ASSERT_PRE_NON_NULL(iterator, "Message iterator");
1429         return bt_self_component_port_input_message_iterator_can_seek_beginning(
1430                 borrow_output_port_message_iterator_upstream_iterator(
1431                         iterator));
1432 }
1433
1434 enum bt_message_iterator_status bt_port_output_message_iterator_seek_ns_from_origin(
1435                 struct bt_port_output_message_iterator *iterator,
1436                 int64_t ns_from_origin)
1437 {
1438         BT_ASSERT_PRE_NON_NULL(iterator, "Message iterator");
1439         return bt_self_component_port_input_message_iterator_seek_ns_from_origin(
1440                 borrow_output_port_message_iterator_upstream_iterator(iterator),
1441                 ns_from_origin);
1442 }
1443
1444 enum bt_message_iterator_status bt_port_output_message_iterator_seek_beginning(
1445                 struct bt_port_output_message_iterator *iterator)
1446 {
1447         BT_ASSERT_PRE_NON_NULL(iterator, "Message iterator");
1448         return bt_self_component_port_input_message_iterator_seek_beginning(
1449                 borrow_output_port_message_iterator_upstream_iterator(
1450                         iterator));
1451 }
1452
1453 void bt_port_output_message_iterator_get_ref(
1454                 const struct bt_port_output_message_iterator *iterator)
1455 {
1456         bt_object_get_ref(iterator);
1457 }
1458
1459 void bt_port_output_message_iterator_put_ref(
1460                 const struct bt_port_output_message_iterator *iterator)
1461 {
1462         bt_object_put_ref(iterator);
1463 }
1464
1465 void bt_self_component_port_input_message_iterator_get_ref(
1466                 const struct bt_self_component_port_input_message_iterator *iterator)
1467 {
1468         bt_object_get_ref(iterator);
1469 }
1470
1471 void bt_self_component_port_input_message_iterator_put_ref(
1472                 const struct bt_self_component_port_input_message_iterator *iterator)
1473 {
1474         bt_object_put_ref(iterator);
1475 }