src/plugins/utils/muxer/muxer.c

   1 /*
   2  * Copyright 2017 Philippe Proulx <pproulx@efficios.com>
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a copy
   5  * of this software and associated documentation files (the "Software"), to deal
   6  * in the Software without restriction, including without limitation the rights
   7  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   8  * copies of the Software, and to permit persons to whom the Software is
   9  * furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included in
  12  * all copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  17  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  18  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  19  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  20  * SOFTWARE.
  21  */
  22
  23 #define BT_COMP_LOG_SELF_COMP (muxer_comp->self_comp)
  24 #define BT_LOG_OUTPUT_LEVEL (muxer_comp->log_level)
  25 #define BT_LOG_TAG "PLUGIN/FLT.UTILS.MUXER"
  26 #include "logging/comp-logging.h"
  27
  28 #include "common/macros.h"
  29 #include "common/uuid.h"
  30 #include <babeltrace2/babeltrace.h>
  31 #include <glib.h>
  32 #include <stdbool.h>
  33 #include <inttypes.h>
  34 #include "common/assert.h"
  35 #include "common/common.h"
  36 #include <stdlib.h>
  37 #include <string.h>
  38
  39 #include "plugins/common/muxing/muxing.h"
  40
  41 #include "muxer.h"
  42
  43 struct muxer_comp {
  44         /* Weak refs */
  45         bt_self_component_filter *self_comp_flt;
  46         bt_self_component *self_comp;
  47
  48         unsigned int next_port_num;
  49         size_t available_input_ports;
  50         bool initializing_muxer_msg_iter;
  51         bt_logging_level log_level;
  52 };
  53
  54 struct muxer_upstream_msg_iter {
  55         struct muxer_comp *muxer_comp;
  56
  57         /* Owned by this, NULL if ended */
  58         bt_self_component_port_input_message_iterator *msg_iter;
  59
  60         /* Contains `const bt_message *`, owned by this */
  61         GQueue *msgs;
  62 };
  63
  64 enum muxer_msg_iter_clock_class_expectation {
  65         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_ANY = 0,
  66         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NONE,
  67         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_ABSOLUTE,
  68         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NOT_ABS_SPEC_UUID,
  69         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NOT_ABS_NO_UUID,
  70 };
  71
  72 struct muxer_msg_iter {
  73         struct muxer_comp *muxer_comp;
  74
  75         /* Weak */
  76         bt_self_message_iterator *self_msg_iter;
  77
  78         /*
  79          * Array of struct muxer_upstream_msg_iter * (owned by this).
  80          *
  81          * NOTE: This array is searched in linearly to find the youngest
  82          * current message. Keep this until benchmarks confirm that
  83          * another data structure is faster than this for our typical
  84          * use cases.
  85          */
  86         GPtrArray *active_muxer_upstream_msg_iters;
  87
  88         /*
  89          * Array of struct muxer_upstream_msg_iter * (owned by this).
  90          *
  91          * We move ended message iterators from
  92          * `active_muxer_upstream_msg_iters` to this array so as to be
  93          * able to restore them when seeking.
  94          */
  95         GPtrArray *ended_muxer_upstream_msg_iters;
  96
  97         /* Last time returned in a message */
  98         int64_t last_returned_ts_ns;
  99
 100         /* Clock class expectation state */
 101         enum muxer_msg_iter_clock_class_expectation clock_class_expectation;
 102
 103         /*
 104          * Expected clock class UUID, only valid when
 105          * clock_class_expectation is
 106          * MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NOT_ABS_SPEC_UUID.
 107          */
 108         bt_uuid_t expected_clock_class_uuid;
 109 };
 110
 111 static
 112 void empty_message_queue(struct muxer_upstream_msg_iter *upstream_msg_iter)
 113 {
 114         const bt_message *msg;
 115
 116         while ((msg = g_queue_pop_head(upstream_msg_iter->msgs))) {
 117                 bt_message_put_ref(msg);
 118         }
 119 }
 120
 121 static
 122 void destroy_muxer_upstream_msg_iter(
 123                 struct muxer_upstream_msg_iter *muxer_upstream_msg_iter)
 124 {
 125         struct muxer_comp *muxer_comp;
 126
 127         if (!muxer_upstream_msg_iter) {
 128                 return;
 129         }
 130
 131         muxer_comp = muxer_upstream_msg_iter->muxer_comp;
 132         BT_COMP_LOGD("Destroying muxer's upstream message iterator wrapper: "
 133                 "addr=%p, msg-iter-addr=%p, queue-len=%u",
 134                 muxer_upstream_msg_iter,
 135                 muxer_upstream_msg_iter->msg_iter,
 136                 muxer_upstream_msg_iter->msgs->length);
 137         bt_self_component_port_input_message_iterator_put_ref(
 138                 muxer_upstream_msg_iter->msg_iter);
 139
 140         if (muxer_upstream_msg_iter->msgs) {
 141                 empty_message_queue(muxer_upstream_msg_iter);
 142                 g_queue_free(muxer_upstream_msg_iter->msgs);
 143         }
 144
 145         g_free(muxer_upstream_msg_iter);
 146 }
 147
 148 static
 149 int muxer_msg_iter_add_upstream_msg_iter(struct muxer_msg_iter *muxer_msg_iter,
 150                 bt_self_component_port_input_message_iterator *self_msg_iter)
 151 {
 152         int ret = 0;
 153         struct muxer_upstream_msg_iter *muxer_upstream_msg_iter =
 154                 g_new0(struct muxer_upstream_msg_iter, 1);
 155         struct muxer_comp *muxer_comp = muxer_msg_iter->muxer_comp;
 156
 157         if (!muxer_upstream_msg_iter) {
 158                 BT_COMP_LOGE_STR("Failed to allocate one muxer's upstream message iterator wrapper.");
 159                 goto error;
 160         }
 161
 162         muxer_upstream_msg_iter->muxer_comp = muxer_comp;
 163         muxer_upstream_msg_iter->msg_iter = self_msg_iter;
 164         bt_self_component_port_input_message_iterator_get_ref(muxer_upstream_msg_iter->msg_iter);
 165         muxer_upstream_msg_iter->msgs = g_queue_new();
 166         if (!muxer_upstream_msg_iter->msgs) {
 167                 BT_COMP_LOGE_STR("Failed to allocate a GQueue.");
 168                 goto error;
 169         }
 170
 171         g_ptr_array_add(muxer_msg_iter->active_muxer_upstream_msg_iters,
 172                 muxer_upstream_msg_iter);
 173         BT_COMP_LOGD("Added muxer's upstream message iterator wrapper: "
 174                 "addr=%p, muxer-msg-iter-addr=%p, msg-iter-addr=%p",
 175                 muxer_upstream_msg_iter, muxer_msg_iter,
 176                 self_msg_iter);
 177
 178         goto end;
 179
 180 error:
 181         g_free(muxer_upstream_msg_iter);
 182         ret = -1;
 183
 184 end:
 185         return ret;
 186 }
 187
 188 static
 189 bt_self_component_add_port_status add_available_input_port(
 190                 bt_self_component_filter *self_comp)
 191 {
 192         struct muxer_comp *muxer_comp = bt_self_component_get_data(
 193                 bt_self_component_filter_as_self_component(self_comp));
 194         bt_self_component_add_port_status status =
 195                 BT_SELF_COMPONENT_ADD_PORT_STATUS_OK;
 196         GString *port_name = NULL;
 197
 198         BT_ASSERT(muxer_comp);
 199         port_name = g_string_new("in");
 200         if (!port_name) {
 201                 BT_COMP_LOGE_STR("Failed to allocate a GString.");
 202                 status = BT_SELF_COMPONENT_ADD_PORT_STATUS_MEMORY_ERROR;
 203                 goto end;
 204         }
 205
 206         g_string_append_printf(port_name, "%u", muxer_comp->next_port_num);
 207         status = bt_self_component_filter_add_input_port(
 208                 self_comp, port_name->str, NULL, NULL);
 209         if (status != BT_SELF_COMPONENT_ADD_PORT_STATUS_OK) {
 210                 BT_COMP_LOGE("Cannot add input port to muxer component: "
 211                         "port-name=\"%s\", comp-addr=%p, status=%s",
 212                         port_name->str, self_comp,
 213                         bt_common_func_status_string(status));
 214                 goto end;
 215         }
 216
 217         muxer_comp->available_input_ports++;
 218         muxer_comp->next_port_num++;
 219         BT_COMP_LOGI("Added one input port to muxer component: "
 220                 "port-name=\"%s\", comp-addr=%p",
 221                 port_name->str, self_comp);
 222
 223 end:
 224         if (port_name) {
 225                 g_string_free(port_name, TRUE);
 226         }
 227
 228         return status;
 229 }
 230
 231 static
 232 bt_self_component_add_port_status create_output_port(
 233                 bt_self_component_filter *self_comp)
 234 {
 235         return bt_self_component_filter_add_output_port(
 236                 self_comp, "out", NULL, NULL);
 237 }
 238
 239 static
 240 void destroy_muxer_comp(struct muxer_comp *muxer_comp)
 241 {
 242         if (!muxer_comp) {
 243                 return;
 244         }
 245
 246         g_free(muxer_comp);
 247 }
 248
 249 BT_HIDDEN
 250 bt_component_class_init_method_status muxer_init(
 251                 bt_self_component_filter *self_comp_flt,
 252                 bt_self_component_filter_configuration *config,
 253                 const bt_value *params, void *init_data)
 254 {
 255         bt_component_class_init_method_status status =
 256                 BT_COMPONENT_CLASS_INIT_METHOD_STATUS_OK;
 257         bt_self_component_add_port_status add_port_status;
 258         bt_self_component *self_comp =
 259                 bt_self_component_filter_as_self_component(self_comp_flt);
 260         struct muxer_comp *muxer_comp = g_new0(struct muxer_comp, 1);
 261         bt_logging_level log_level = bt_component_get_logging_level(
 262                 bt_self_component_as_component(self_comp));
 263
 264         BT_COMP_LOG_CUR_LVL(BT_LOG_INFO, log_level, self_comp,
 265                 "Initializing muxer component: "
 266                 "comp-addr=%p, params-addr=%p", self_comp, params);
 267
 268         if (!muxer_comp) {
 269                 BT_COMP_LOG_CUR_LVL(BT_LOG_ERROR, log_level, self_comp,
 270                         "Failed to allocate one muxer component.");
 271                 goto error;
 272         }
 273
 274         muxer_comp->log_level = log_level;
 275         muxer_comp->self_comp = self_comp;
 276         muxer_comp->self_comp_flt = self_comp_flt;
 277
 278         bt_self_component_set_data(self_comp, muxer_comp);
 279         add_port_status = add_available_input_port(self_comp_flt);
 280         if (add_port_status != BT_SELF_COMPONENT_ADD_PORT_STATUS_OK) {
 281                 BT_COMP_LOGE("Cannot ensure that at least one muxer component's input port is available: "
 282                         "muxer-comp-addr=%p, status=%s",
 283                         muxer_comp,
 284                         bt_common_func_status_string(add_port_status));
 285                 if (add_port_status ==
 286                                 BT_SELF_COMPONENT_ADD_PORT_STATUS_MEMORY_ERROR) {
 287                         status = BT_COMPONENT_CLASS_INIT_METHOD_STATUS_MEMORY_ERROR;
 288                 } else {
 289                         status = BT_COMPONENT_CLASS_INIT_METHOD_STATUS_ERROR;
 290                 }
 291
 292                 goto error;
 293         }
 294
 295         add_port_status = create_output_port(self_comp_flt);
 296         if (add_port_status != BT_SELF_COMPONENT_ADD_PORT_STATUS_OK) {
 297                 BT_COMP_LOGE("Cannot create muxer component's output port: "
 298                         "muxer-comp-addr=%p, status=%s",
 299                         muxer_comp,
 300                         bt_common_func_status_string(add_port_status));
 301                 if (add_port_status ==
 302                                 BT_SELF_COMPONENT_ADD_PORT_STATUS_MEMORY_ERROR) {
 303                         status = BT_COMPONENT_CLASS_INIT_METHOD_STATUS_MEMORY_ERROR;
 304                 } else {
 305                         status = BT_COMPONENT_CLASS_INIT_METHOD_STATUS_ERROR;
 306                 }
 307
 308                 goto error;
 309         }
 310
 311         BT_COMP_LOGI("Initialized muxer component: "
 312                 "comp-addr=%p, params-addr=%p, muxer-comp-addr=%p",
 313                 self_comp, params, muxer_comp);
 314
 315         goto end;
 316
 317 error:
 318         destroy_muxer_comp(muxer_comp);
 319         bt_self_component_set_data(self_comp, NULL);
 320
 321         if (status == BT_COMPONENT_CLASS_INIT_METHOD_STATUS_OK) {
 322                 status = BT_COMPONENT_CLASS_INIT_METHOD_STATUS_ERROR;
 323         }
 324
 325 end:
 326         return status;
 327 }
 328
 329 BT_HIDDEN
 330 void muxer_finalize(bt_self_component_filter *self_comp)
 331 {
 332         struct muxer_comp *muxer_comp = bt_self_component_get_data(
 333                 bt_self_component_filter_as_self_component(self_comp));
 334
 335         BT_COMP_LOGI("Finalizing muxer component: comp-addr=%p",
 336                 self_comp);
 337         destroy_muxer_comp(muxer_comp);
 338 }
 339
 340 static
 341 bt_self_component_port_input_message_iterator_create_from_message_iterator_status
 342 create_msg_iter_on_input_port(struct muxer_comp *muxer_comp,
 343                 struct muxer_msg_iter *muxer_msg_iter,
 344                 bt_self_component_port_input *self_port,
 345                 bt_self_component_port_input_message_iterator **msg_iter)
 346 {
 347         const bt_port *port = bt_self_component_port_as_port(
 348                 bt_self_component_port_input_as_self_component_port(
 349                         self_port));
 350         bt_self_component_port_input_message_iterator_create_from_message_iterator_status
 351                 status;
 352
 353         BT_ASSERT(port);
 354         BT_ASSERT(bt_port_is_connected(port));
 355
 356         // TODO: Advance the iterator to >= the time of the latest
 357         //       returned message by the muxer message
 358         //       iterator which creates it.
 359         status = bt_self_component_port_input_message_iterator_create_from_message_iterator(
 360                 muxer_msg_iter->self_msg_iter, self_port, msg_iter);
 361         if (status != BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_CREATE_FROM_MESSAGE_ITERATOR_STATUS_OK) {
 362                 BT_COMP_LOGE("Cannot create upstream message iterator on input port: "
 363                         "port-addr=%p, port-name=\"%s\"",
 364                         port, bt_port_get_name(port));
 365                 goto end;
 366         }
 367
 368         BT_COMP_LOGI("Created upstream message iterator on input port: "
 369                 "port-addr=%p, port-name=\"%s\", msg-iter-addr=%p",
 370                 port, bt_port_get_name(port), msg_iter);
 371
 372 end:
 373         return status;
 374 }
 375
 376 static
 377 bt_component_class_message_iterator_next_method_status muxer_upstream_msg_iter_next(
 378                 struct muxer_upstream_msg_iter *muxer_upstream_msg_iter,
 379                 bool *is_ended)
 380 {
 381         struct muxer_comp *muxer_comp =
 382                 muxer_upstream_msg_iter->muxer_comp;
 383         bt_component_class_message_iterator_next_method_status status;
 384         bt_message_iterator_next_status input_port_iter_status;
 385         bt_message_array_const msgs;
 386         uint64_t i;
 387         uint64_t count;
 388
 389         BT_COMP_LOGD("Calling upstream message iterator's \"next\" method: "
 390                 "muxer-upstream-msg-iter-wrap-addr=%p, msg-iter-addr=%p",
 391                 muxer_upstream_msg_iter,
 392                 muxer_upstream_msg_iter->msg_iter);
 393         input_port_iter_status = bt_self_component_port_input_message_iterator_next(
 394                 muxer_upstream_msg_iter->msg_iter, &msgs, &count);
 395         BT_COMP_LOGD("Upstream message iterator's \"next\" method returned: "
 396                 "status=%s",
 397                 bt_common_func_status_string(input_port_iter_status));
 398
 399         switch (input_port_iter_status) {
 400         case BT_MESSAGE_ITERATOR_NEXT_STATUS_OK:
 401                 /*
 402                  * Message iterator's current message is
 403                  * valid: it must be considered for muxing operations.
 404                  */
 405                 BT_COMP_LOGD_STR("Validated upstream message iterator wrapper.");
 406                 BT_ASSERT(count > 0);
 407
 408                 /* Move messages to our queue */
 409                 for (i = 0; i < count; i++) {
 410                         /*
 411                          * Push to tail in order; other side
 412                          * (muxer_msg_iter_do_next_one()) consumes
 413                          * from the head first.
 414                          */
 415                         g_queue_push_tail(muxer_upstream_msg_iter->msgs,
 416                                 (void *) msgs[i]);
 417                 }
 418                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK;
 419                 break;
 420         case BT_MESSAGE_ITERATOR_NEXT_STATUS_AGAIN:
 421                 /*
 422                  * Message iterator's current message is not
 423                  * valid anymore. Return
 424                  * BT_MESSAGE_ITERATOR_NEXT_STATUS_AGAIN immediately.
 425                  */
 426                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_AGAIN;
 427                 break;
 428         case BT_MESSAGE_ITERATOR_NEXT_STATUS_END:       /* Fall-through. */
 429                 /*
 430                  * Message iterator reached the end: release it. It
 431                  * won't be considered again to find the youngest
 432                  * message.
 433                  */
 434                 *is_ended = true;
 435                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK;
 436                 break;
 437         default:
 438                 /* Error or unsupported status code */
 439                 BT_COMP_LOGE("Error or unsupported status code: "
 440                         "status-code=%d", input_port_iter_status);
 441                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_ERROR;
 442                 break;
 443         }
 444
 445         return status;
 446 }
 447
 448 static
 449 int get_msg_ts_ns(struct muxer_comp *muxer_comp,
 450                 struct muxer_msg_iter *muxer_msg_iter,
 451                 const bt_message *msg, int64_t last_returned_ts_ns,
 452                 int64_t *ts_ns)
 453 {
 454         const bt_clock_snapshot *clock_snapshot = NULL;
 455         int ret = 0;
 456         const bt_stream_class *stream_class = NULL;
 457         bt_message_type msg_type;
 458
 459         BT_ASSERT(msg);
 460         BT_ASSERT(ts_ns);
 461         BT_COMP_LOGD("Getting message's timestamp: "
 462                 "muxer-msg-iter-addr=%p, msg-addr=%p, "
 463                 "last-returned-ts=%" PRId64,
 464                 muxer_msg_iter, msg, last_returned_ts_ns);
 465
 466         if (G_UNLIKELY(muxer_msg_iter->clock_class_expectation ==
 467                         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NONE)) {
 468                 *ts_ns = last_returned_ts_ns;
 469                 goto end;
 470         }
 471
 472         msg_type = bt_message_get_type(msg);
 473
 474         if (G_UNLIKELY(msg_type == BT_MESSAGE_TYPE_PACKET_BEGINNING)) {
 475                 stream_class = bt_stream_borrow_class_const(
 476                         bt_packet_borrow_stream_const(
 477                                 bt_message_packet_beginning_borrow_packet_const(
 478                                         msg)));
 479         } else if (G_UNLIKELY(msg_type == BT_MESSAGE_TYPE_PACKET_END)) {
 480                 stream_class = bt_stream_borrow_class_const(
 481                         bt_packet_borrow_stream_const(
 482                                 bt_message_packet_end_borrow_packet_const(
 483                                         msg)));
 484         } else if (G_UNLIKELY(msg_type == BT_MESSAGE_TYPE_DISCARDED_EVENTS)) {
 485                 stream_class = bt_stream_borrow_class_const(
 486                         bt_message_discarded_events_borrow_stream_const(msg));
 487         } else if (G_UNLIKELY(msg_type == BT_MESSAGE_TYPE_DISCARDED_PACKETS)) {
 488                 stream_class = bt_stream_borrow_class_const(
 489                         bt_message_discarded_packets_borrow_stream_const(msg));
 490         }
 491
 492         switch (msg_type) {
 493         case BT_MESSAGE_TYPE_EVENT:
 494                 BT_ASSERT(bt_message_event_borrow_stream_class_default_clock_class_const(
 495                                 msg));
 496                 clock_snapshot = bt_message_event_borrow_default_clock_snapshot_const(
 497                         msg);
 498                 break;
 499         case BT_MESSAGE_TYPE_PACKET_BEGINNING:
 500                 if (bt_stream_class_packets_have_beginning_default_clock_snapshot(
 501                                 stream_class)) {
 502                         clock_snapshot = bt_message_packet_beginning_borrow_default_clock_snapshot_const(
 503                                 msg);
 504                 } else {
 505                         goto no_clock_snapshot;
 506                 }
 507
 508                 break;
 509         case BT_MESSAGE_TYPE_PACKET_END:
 510                 if (bt_stream_class_packets_have_end_default_clock_snapshot(
 511                                 stream_class)) {
 512                         clock_snapshot = bt_message_packet_end_borrow_default_clock_snapshot_const(
 513                                 msg);
 514                 } else {
 515                         goto no_clock_snapshot;
 516                 }
 517
 518                 break;
 519         case BT_MESSAGE_TYPE_STREAM_BEGINNING:
 520         {
 521                 enum bt_message_stream_clock_snapshot_state snapshot_state =
 522                         bt_message_stream_beginning_borrow_default_clock_snapshot_const(
 523                                 msg, &clock_snapshot);
 524                 if (snapshot_state == BT_MESSAGE_STREAM_CLOCK_SNAPSHOT_STATE_UNKNOWN) {
 525                         goto no_clock_snapshot;
 526                 }
 527
 528                 break;
 529         }
 530         case BT_MESSAGE_TYPE_STREAM_END:
 531         {
 532                 enum bt_message_stream_clock_snapshot_state snapshot_state =
 533                         bt_message_stream_end_borrow_default_clock_snapshot_const(
 534                                 msg, &clock_snapshot);
 535                 if (snapshot_state == BT_MESSAGE_STREAM_CLOCK_SNAPSHOT_STATE_UNKNOWN) {
 536                         goto no_clock_snapshot;
 537                 }
 538
 539                 break;
 540         }
 541         case BT_MESSAGE_TYPE_DISCARDED_EVENTS:
 542                 if (bt_stream_class_discarded_events_have_default_clock_snapshots(
 543                                 stream_class)) {
 544                         clock_snapshot = bt_message_discarded_events_borrow_beginning_default_clock_snapshot_const(
 545                                 msg);
 546                 } else {
 547                         goto no_clock_snapshot;
 548                 }
 549
 550                 break;
 551         case BT_MESSAGE_TYPE_DISCARDED_PACKETS:
 552                 if (bt_stream_class_discarded_packets_have_default_clock_snapshots(
 553                                 stream_class)) {
 554                         clock_snapshot = bt_message_discarded_packets_borrow_beginning_default_clock_snapshot_const(
 555                                 msg);
 556                 } else {
 557                         goto no_clock_snapshot;
 558                 }
 559
 560                 break;
 561         case BT_MESSAGE_TYPE_MESSAGE_ITERATOR_INACTIVITY:
 562                 clock_snapshot = bt_message_message_iterator_inactivity_borrow_default_clock_snapshot_const(
 563                         msg);
 564                 break;
 565         default:
 566                 /* All the other messages have a higher priority */
 567                 BT_COMP_LOGD_STR("Message has no timestamp: using the last returned timestamp.");
 568                 *ts_ns = last_returned_ts_ns;
 569                 goto end;
 570         }
 571
 572         ret = bt_clock_snapshot_get_ns_from_origin(clock_snapshot, ts_ns);
 573         if (ret) {
 574                 BT_COMP_LOGE("Cannot get nanoseconds from Epoch of clock snapshot: "
 575                         "clock-snapshot-addr=%p", clock_snapshot);
 576                 goto error;
 577         }
 578
 579         goto end;
 580
 581 no_clock_snapshot:
 582         BT_COMP_LOGD_STR("Message's default clock snapshot is missing: "
 583                 "using the last returned timestamp.");
 584         *ts_ns = last_returned_ts_ns;
 585         goto end;
 586
 587 error:
 588         ret = -1;
 589
 590 end:
 591         if (ret == 0) {
 592                 BT_COMP_LOGD("Found message's timestamp: "
 593                         "muxer-msg-iter-addr=%p, msg-addr=%p, "
 594                         "last-returned-ts=%" PRId64 ", ts=%" PRId64,
 595                         muxer_msg_iter, msg, last_returned_ts_ns,
 596                         *ts_ns);
 597         }
 598
 599         return ret;
 600 }
 601
 602 static inline
 603 int validate_clock_class(struct muxer_msg_iter *muxer_msg_iter,
 604                 struct muxer_comp *muxer_comp,
 605                 const bt_clock_class *clock_class)
 606 {
 607         int ret = 0;
 608         const uint8_t *cc_uuid;
 609         const char *cc_name;
 610
 611         BT_ASSERT(clock_class);
 612         cc_uuid = bt_clock_class_get_uuid(clock_class);
 613         cc_name = bt_clock_class_get_name(clock_class);
 614
 615         if (muxer_msg_iter->clock_class_expectation ==
 616                         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_ANY) {
 617                 /*
 618                  * This is the first clock class that this muxer message
 619                  * iterator encounters. Its properties determine what to expect
 620                  * for the whole lifetime of the iterator.
 621                  */
 622                 if (bt_clock_class_origin_is_unix_epoch(clock_class)) {
 623                         /* Expect absolute clock classes */
 624                         muxer_msg_iter->clock_class_expectation =
 625                                 MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_ABSOLUTE;
 626                 } else {
 627                         if (cc_uuid) {
 628                                 /*
 629                                  * Expect non-absolute clock classes
 630                                  * with a specific UUID.
 631                                  */
 632                                 muxer_msg_iter->clock_class_expectation =
 633                                         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NOT_ABS_SPEC_UUID;
 634                                 bt_uuid_copy(muxer_msg_iter->expected_clock_class_uuid, cc_uuid);
 635                         } else {
 636                                 /*
 637                                  * Expect non-absolute clock classes
 638                                  * with no UUID.
 639                                  */
 640                                 muxer_msg_iter->clock_class_expectation =
 641                                         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NOT_ABS_NO_UUID;
 642                         }
 643                 }
 644         }
 645
 646         switch (muxer_msg_iter->clock_class_expectation) {
 647         case MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_ABSOLUTE:
 648                 if (!bt_clock_class_origin_is_unix_epoch(clock_class)) {
 649                         BT_COMP_LOGE("Expecting an absolute clock class, "
 650                                 "but got a non-absolute one: "
 651                                 "clock-class-addr=%p, clock-class-name=\"%s\"",
 652                                 clock_class, cc_name);
 653                         goto error;
 654                 }
 655                 break;
 656         case MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NOT_ABS_NO_UUID:
 657                 if (bt_clock_class_origin_is_unix_epoch(clock_class)) {
 658                         BT_COMP_LOGE("Expecting a non-absolute clock class with no UUID, "
 659                                 "but got an absolute one: "
 660                                 "clock-class-addr=%p, clock-class-name=\"%s\"",
 661                                 clock_class, cc_name);
 662                         goto error;
 663                 }
 664
 665                 if (cc_uuid) {
 666                         BT_COMP_LOGE("Expecting a non-absolute clock class with no UUID, "
 667                                 "but got one with a UUID: "
 668                                 "clock-class-addr=%p, clock-class-name=\"%s\", "
 669                                 "uuid=\"" BT_UUID_FMT "\"",
 670                                 clock_class, cc_name, BT_UUID_FMT_VALUES(cc_uuid));
 671                         goto error;
 672                 }
 673                 break;
 674         case MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NOT_ABS_SPEC_UUID:
 675                 if (bt_clock_class_origin_is_unix_epoch(clock_class)) {
 676                         BT_COMP_LOGE("Expecting a non-absolute clock class with a specific UUID, "
 677                                 "but got an absolute one: "
 678                                 "clock-class-addr=%p, clock-class-name=\"%s\"",
 679                                 clock_class, cc_name);
 680                         goto error;
 681                 }
 682
 683                 if (!cc_uuid) {
 684                         BT_COMP_LOGE("Expecting a non-absolute clock class with a specific UUID, "
 685                                 "but got one with no UUID: "
 686                                 "clock-class-addr=%p, clock-class-name=\"%s\"",
 687                                 clock_class, cc_name);
 688                         goto error;
 689                 }
 690
 691                 if (bt_uuid_compare(muxer_msg_iter->expected_clock_class_uuid, cc_uuid) != 0) {
 692                         BT_COMP_LOGE("Expecting a non-absolute clock class with a specific UUID, "
 693                                 "but got one with different UUID: "
 694                                 "clock-class-addr=%p, clock-class-name=\"%s\", "
 695                                 "expected-uuid=\"" BT_UUID_FMT "\", "
 696                                 "uuid=\"" BT_UUID_FMT "\"",
 697                                 clock_class, cc_name,
 698                                 BT_UUID_FMT_VALUES(muxer_msg_iter->expected_clock_class_uuid),
 699                                 BT_UUID_FMT_VALUES(cc_uuid));
 700                         goto error;
 701                 }
 702                 break;
 703         case MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NONE:
 704                 BT_COMP_LOGE("Expecting no clock class, but got one: "
 705                         "clock-class-addr=%p, clock-class-name=\"%s\"",
 706                         clock_class, cc_name);
 707                 goto error;
 708         default:
 709                 /* Unexpected */
 710                 BT_COMP_LOGF("Unexpected clock class expectation: "
 711                         "expectation-code=%d",
 712                         muxer_msg_iter->clock_class_expectation);
 713                 abort();
 714         }
 715
 716         goto end;
 717
 718 error:
 719         ret = -1;
 720
 721 end:
 722         return ret;
 723 }
 724
 725 static inline
 726 int validate_new_stream_clock_class(struct muxer_msg_iter *muxer_msg_iter,
 727                 struct muxer_comp *muxer_comp, const bt_stream *stream)
 728 {
 729         int ret = 0;
 730         const bt_stream_class *stream_class =
 731                 bt_stream_borrow_class_const(stream);
 732         const bt_clock_class *clock_class =
 733                 bt_stream_class_borrow_default_clock_class_const(stream_class);
 734
 735         if (!clock_class) {
 736                 if (muxer_msg_iter->clock_class_expectation ==
 737                         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_ANY) {
 738                         /* Expect no clock class */
 739                         muxer_msg_iter->clock_class_expectation =
 740                                 MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NONE;
 741                 } else if (muxer_msg_iter->clock_class_expectation !=
 742                                 MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NONE) {
 743                         BT_COMP_LOGE("Expecting stream class without a default clock class: "
 744                                 "stream-class-addr=%p, stream-class-name=\"%s\", "
 745                                 "stream-class-id=%" PRIu64,
 746                                 stream_class, bt_stream_class_get_name(stream_class),
 747                                 bt_stream_class_get_id(stream_class));
 748                         ret = -1;
 749                 }
 750
 751                 goto end;
 752         }
 753
 754         ret = validate_clock_class(muxer_msg_iter, muxer_comp, clock_class);
 755
 756 end:
 757         return ret;
 758 }
 759
 760 /*
 761  * This function finds the youngest available message amongst the
 762  * non-ended upstream message iterators and returns the upstream
 763  * message iterator which has it, or
 764  * BT_MESSAGE_ITERATOR_STATUS_END if there's no available
 765  * message.
 766  *
 767  * This function does NOT:
 768  *
 769  * * Update any upstream message iterator.
 770  * * Check the upstream message iterators to retry.
 771  *
 772  * On sucess, this function sets *muxer_upstream_msg_iter to the
 773  * upstream message iterator of which the current message is
 774  * the youngest, and sets *ts_ns to its time.
 775  */
 776 static
 777 bt_component_class_message_iterator_next_method_status
 778 muxer_msg_iter_youngest_upstream_msg_iter(
 779                 struct muxer_comp *muxer_comp,
 780                 struct muxer_msg_iter *muxer_msg_iter,
 781                 struct muxer_upstream_msg_iter **muxer_upstream_msg_iter,
 782                 int64_t *ts_ns)
 783 {
 784         size_t i;
 785         int ret;
 786         int64_t youngest_ts_ns = INT64_MAX;
 787         bt_component_class_message_iterator_next_method_status status =
 788                 BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK;
 789
 790         BT_ASSERT(muxer_comp);
 791         BT_ASSERT(muxer_msg_iter);
 792         BT_ASSERT(muxer_upstream_msg_iter);
 793         *muxer_upstream_msg_iter = NULL;
 794
 795         for (i = 0; i < muxer_msg_iter->active_muxer_upstream_msg_iters->len;
 796                         i++) {
 797                 const bt_message *msg;
 798                 struct muxer_upstream_msg_iter *cur_muxer_upstream_msg_iter =
 799                         g_ptr_array_index(
 800                                 muxer_msg_iter->active_muxer_upstream_msg_iters,
 801                                 i);
 802                 int64_t msg_ts_ns;
 803
 804                 if (!cur_muxer_upstream_msg_iter->msg_iter) {
 805                         /* This upstream message iterator is ended */
 806                         BT_COMP_LOGT("Skipping ended upstream message iterator: "
 807                                 "muxer-upstream-msg-iter-wrap-addr=%p",
 808                                 cur_muxer_upstream_msg_iter);
 809                         continue;
 810                 }
 811
 812                 BT_ASSERT(cur_muxer_upstream_msg_iter->msgs->length > 0);
 813                 msg = g_queue_peek_head(cur_muxer_upstream_msg_iter->msgs);
 814                 BT_ASSERT(msg);
 815
 816                 if (G_UNLIKELY(bt_message_get_type(msg) ==
 817                                 BT_MESSAGE_TYPE_STREAM_BEGINNING)) {
 818                         ret = validate_new_stream_clock_class(
 819                                 muxer_msg_iter, muxer_comp,
 820                                 bt_message_stream_beginning_borrow_stream_const(
 821                                         msg));
 822                         if (ret) {
 823                                 /*
 824                                  * validate_new_stream_clock_class() logs
 825                                  * errors.
 826                                  */
 827                                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_ERROR;
 828                                 goto end;
 829                         }
 830                 } else if (G_UNLIKELY(bt_message_get_type(msg) ==
 831                                 BT_MESSAGE_TYPE_MESSAGE_ITERATOR_INACTIVITY)) {
 832                         const bt_clock_snapshot *cs;
 833
 834                         cs = bt_message_message_iterator_inactivity_borrow_default_clock_snapshot_const(
 835                                 msg);
 836                         ret = validate_clock_class(muxer_msg_iter, muxer_comp,
 837                                 bt_clock_snapshot_borrow_clock_class_const(cs));
 838                         if (ret) {
 839                                 /* validate_clock_class() logs errors */
 840                                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_ERROR;
 841                                 goto end;
 842                         }
 843                 }
 844
 845                 ret = get_msg_ts_ns(muxer_comp, muxer_msg_iter, msg,
 846                         muxer_msg_iter->last_returned_ts_ns, &msg_ts_ns);
 847                 if (ret) {
 848                         /* get_msg_ts_ns() logs errors */
 849                         *muxer_upstream_msg_iter = NULL;
 850                         status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_ERROR;
 851                         goto end;
 852                 }
 853
 854                 /*
 855                  * Update the current message iterator if it has not been set
 856                  * yet, or if its current message has a timestamp smaller than
 857                  * the previously selected youngest message.
 858                  */
 859                 if (G_UNLIKELY(*muxer_upstream_msg_iter == NULL) ||
 860                                 msg_ts_ns < youngest_ts_ns) {
 861                         *muxer_upstream_msg_iter =
 862                                 cur_muxer_upstream_msg_iter;
 863                         youngest_ts_ns = msg_ts_ns;
 864                         *ts_ns = youngest_ts_ns;
 865                 } else if (msg_ts_ns == youngest_ts_ns) {
 866                         /*
 867                          * The currently selected message to be sent downstream
 868                          * next has the exact same timestamp that of the
 869                          * current candidate message. We must break the tie
 870                          * in a predictable manner.
 871                          */
 872                         const bt_message *selected_msg = g_queue_peek_head(
 873                                 (*muxer_upstream_msg_iter)->msgs);
 874                         BT_COMP_LOGD_STR("Two of the next message candidates have the same timestamps, pick one deterministically.");
 875
 876                         /*
 877                          * Order the messages in an arbitrary but determinitic
 878                          * way.
 879                          */
 880                         ret = common_muxing_compare_messages(msg, selected_msg);
 881                         if (ret < 0) {
 882                                 /*
 883                                  * The `msg` should go first. Update the next
 884                                  * iterator and the current timestamp.
 885                                  */
 886                                 *muxer_upstream_msg_iter =
 887                                         cur_muxer_upstream_msg_iter;
 888                                 youngest_ts_ns = msg_ts_ns;
 889                                 *ts_ns = youngest_ts_ns;
 890                         } else if (ret == 0) {
 891                                 /* Unable to pick which one should go first. */
 892                                 BT_COMP_LOGW("Cannot deterministically pick next upstream message iterator because they have identical next messages: "
 893                                         "muxer-upstream-msg-iter-wrap-addr=%p"
 894                                         "cur-muxer-upstream-msg-iter-wrap-addr=%p",
 895                                         *muxer_upstream_msg_iter,
 896                                         cur_muxer_upstream_msg_iter);
 897                         }
 898                 }
 899         }
 900
 901         if (!*muxer_upstream_msg_iter) {
 902                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_END;
 903                 *ts_ns = INT64_MIN;
 904         }
 905
 906 end:
 907         return status;
 908 }
 909
 910 static
 911 bt_component_class_message_iterator_next_method_status
 912 validate_muxer_upstream_msg_iter(
 913         struct muxer_upstream_msg_iter *muxer_upstream_msg_iter,
 914         bool *is_ended)
 915 {
 916         struct muxer_comp *muxer_comp =
 917                 muxer_upstream_msg_iter->muxer_comp;
 918         bt_component_class_message_iterator_next_method_status status =
 919                 BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK;
 920
 921         BT_COMP_LOGD("Validating muxer's upstream message iterator wrapper: "
 922                 "muxer-upstream-msg-iter-wrap-addr=%p",
 923                 muxer_upstream_msg_iter);
 924
 925         if (muxer_upstream_msg_iter->msgs->length > 0 ||
 926                         !muxer_upstream_msg_iter->msg_iter) {
 927                 BT_COMP_LOGD("Already valid or not considered: "
 928                         "queue-len=%u, upstream-msg-iter-addr=%p",
 929                         muxer_upstream_msg_iter->msgs->length,
 930                         muxer_upstream_msg_iter->msg_iter);
 931                 goto end;
 932         }
 933
 934         /* muxer_upstream_msg_iter_next() logs details/errors */
 935         status = muxer_upstream_msg_iter_next(muxer_upstream_msg_iter,
 936                 is_ended);
 937
 938 end:
 939         return status;
 940 }
 941
 942 static
 943 bt_component_class_message_iterator_next_method_status
 944 validate_muxer_upstream_msg_iters(
 945                 struct muxer_msg_iter *muxer_msg_iter)
 946 {
 947         struct muxer_comp *muxer_comp = muxer_msg_iter->muxer_comp;
 948         bt_component_class_message_iterator_next_method_status status =
 949                 BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK;
 950         size_t i;
 951
 952         BT_COMP_LOGD("Validating muxer's upstream message iterator wrappers: "
 953                 "muxer-msg-iter-addr=%p", muxer_msg_iter);
 954
 955         for (i = 0; i < muxer_msg_iter->active_muxer_upstream_msg_iters->len;
 956                         i++) {
 957                 bool is_ended = false;
 958                 struct muxer_upstream_msg_iter *muxer_upstream_msg_iter =
 959                         g_ptr_array_index(
 960                                 muxer_msg_iter->active_muxer_upstream_msg_iters,
 961                                 i);
 962
 963                 status = validate_muxer_upstream_msg_iter(
 964                         muxer_upstream_msg_iter, &is_ended);
 965                 if (status != BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK) {
 966                         if (status < 0) {
 967                                 BT_COMP_LOGE("Cannot validate muxer's upstream message iterator wrapper: "
 968                                         "muxer-msg-iter-addr=%p, "
 969                                         "muxer-upstream-msg-iter-wrap-addr=%p",
 970                                         muxer_msg_iter,
 971                                         muxer_upstream_msg_iter);
 972                         } else {
 973                                 BT_COMP_LOGD("Cannot validate muxer's upstream message iterator wrapper: "
 974                                         "muxer-msg-iter-addr=%p, "
 975                                         "muxer-upstream-msg-iter-wrap-addr=%p",
 976                                         muxer_msg_iter,
 977                                         muxer_upstream_msg_iter);
 978                         }
 979
 980                         goto end;
 981                 }
 982
 983                 /*
 984                  * Move this muxer upstream message iterator to the
 985                  * array of ended iterators if it's ended.
 986                  */
 987                 if (G_UNLIKELY(is_ended)) {
 988                         BT_COMP_LOGD("Muxer's upstream message iterator wrapper: ended or canceled: "
 989                                 "muxer-msg-iter-addr=%p, "
 990                                 "muxer-upstream-msg-iter-wrap-addr=%p",
 991                                 muxer_msg_iter, muxer_upstream_msg_iter);
 992                         g_ptr_array_add(
 993                                 muxer_msg_iter->ended_muxer_upstream_msg_iters,
 994                                 muxer_upstream_msg_iter);
 995                         muxer_msg_iter->active_muxer_upstream_msg_iters->pdata[i] = NULL;
 996
 997                         /*
 998                          * Use g_ptr_array_remove_fast() because the
 999                          * order of those elements is not important.
1000                          */
1001                         g_ptr_array_remove_index_fast(
1002                                 muxer_msg_iter->active_muxer_upstream_msg_iters,
1003                                 i);
1004                         i--;
1005                 }
1006         }
1007
1008 end:
1009         return status;
1010 }
1011
1012 static inline
1013 bt_component_class_message_iterator_next_method_status muxer_msg_iter_do_next_one(
1014                 struct muxer_comp *muxer_comp,
1015                 struct muxer_msg_iter *muxer_msg_iter,
1016                 const bt_message **msg)
1017 {
1018         bt_component_class_message_iterator_next_method_status status;
1019         struct muxer_upstream_msg_iter *muxer_upstream_msg_iter = NULL;
1020         int64_t next_return_ts;
1021
1022         status = validate_muxer_upstream_msg_iters(muxer_msg_iter);
1023         if (status != BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK) {
1024                 /* validate_muxer_upstream_msg_iters() logs details */
1025                 goto end;
1026         }
1027
1028         /*
1029          * At this point we know that all the existing upstream
1030          * message iterators are valid. We can find the one,
1031          * amongst those, of which the current message is the
1032          * youngest.
1033          */
1034         status = muxer_msg_iter_youngest_upstream_msg_iter(muxer_comp,
1035                         muxer_msg_iter, &muxer_upstream_msg_iter,
1036                         &next_return_ts);
1037         if (status < 0 || status == BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_END) {
1038                 if (status < 0) {
1039                         BT_COMP_LOGE("Cannot find the youngest upstream message iterator wrapper: "
1040                                 "status=%s",
1041                                 bt_common_func_status_string(status));
1042                 } else {
1043                         BT_COMP_LOGD("Cannot find the youngest upstream message iterator wrapper: "
1044                                 "status=%s",
1045                                 bt_common_func_status_string(status));
1046                 }
1047
1048                 goto end;
1049         }
1050
1051         if (next_return_ts < muxer_msg_iter->last_returned_ts_ns) {
1052                 BT_COMP_LOGE("Youngest upstream message iterator wrapper's timestamp is less than muxer's message iterator's last returned timestamp: "
1053                         "muxer-msg-iter-addr=%p, ts=%" PRId64 ", "
1054                         "last-returned-ts=%" PRId64,
1055                         muxer_msg_iter, next_return_ts,
1056                         muxer_msg_iter->last_returned_ts_ns);
1057                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_ERROR;
1058                 goto end;
1059         }
1060
1061         BT_COMP_LOGD("Found youngest upstream message iterator wrapper: "
1062                 "muxer-msg-iter-addr=%p, "
1063                 "muxer-upstream-msg-iter-wrap-addr=%p, "
1064                 "ts=%" PRId64,
1065                 muxer_msg_iter, muxer_upstream_msg_iter, next_return_ts);
1066         BT_ASSERT(status == BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK);
1067         BT_ASSERT(muxer_upstream_msg_iter);
1068
1069         /*
1070          * Consume from the queue's head: other side
1071          * (muxer_upstream_msg_iter_next()) writes to the tail.
1072          */
1073         *msg = g_queue_pop_head(muxer_upstream_msg_iter->msgs);
1074         BT_ASSERT(*msg);
1075         muxer_msg_iter->last_returned_ts_ns = next_return_ts;
1076
1077 end:
1078         return status;
1079 }
1080
1081 static
1082 bt_component_class_message_iterator_next_method_status muxer_msg_iter_do_next(
1083                 struct muxer_comp *muxer_comp,
1084                 struct muxer_msg_iter *muxer_msg_iter,
1085                 bt_message_array_const msgs, uint64_t capacity,
1086                 uint64_t *count)
1087 {
1088         bt_component_class_message_iterator_next_method_status status =
1089                 BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK;
1090         uint64_t i = 0;
1091
1092         while (i < capacity && status == BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK) {
1093                 status = muxer_msg_iter_do_next_one(muxer_comp,
1094                         muxer_msg_iter, &msgs[i]);
1095                 if (status == BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK) {
1096                         i++;
1097                 }
1098         }
1099
1100         if (i > 0) {
1101                 /*
1102                  * Even if muxer_msg_iter_do_next_one() returned
1103                  * something else than
1104                  * BT_MESSAGE_ITERATOR_STATUS_OK, we accumulated
1105                  * message objects in the output message
1106                  * array, so we need to return
1107                  * BT_MESSAGE_ITERATOR_STATUS_OK so that they are
1108                  * transfered to downstream. This other status occurs
1109                  * again the next time muxer_msg_iter_do_next() is
1110                  * called, possibly without any accumulated
1111                  * message, in which case we'll return it.
1112                  */
1113                 *count = i;
1114                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK;
1115         }
1116
1117         return status;
1118 }
1119
1120 static
1121 void destroy_muxer_msg_iter(struct muxer_msg_iter *muxer_msg_iter)
1122 {
1123         struct muxer_comp *muxer_comp;
1124
1125         if (!muxer_msg_iter) {
1126                 return;
1127         }
1128
1129         muxer_comp = muxer_msg_iter->muxer_comp;
1130         BT_COMP_LOGD("Destroying muxer component's message iterator: "
1131                 "muxer-msg-iter-addr=%p", muxer_msg_iter);
1132
1133         if (muxer_msg_iter->active_muxer_upstream_msg_iters) {
1134                 BT_COMP_LOGD_STR("Destroying muxer's active upstream message iterator wrappers.");
1135                 g_ptr_array_free(
1136                         muxer_msg_iter->active_muxer_upstream_msg_iters, TRUE);
1137         }
1138
1139         if (muxer_msg_iter->ended_muxer_upstream_msg_iters) {
1140                 BT_COMP_LOGD_STR("Destroying muxer's ended upstream message iterator wrappers.");
1141                 g_ptr_array_free(
1142                         muxer_msg_iter->ended_muxer_upstream_msg_iters, TRUE);
1143         }
1144
1145         g_free(muxer_msg_iter);
1146 }
1147
1148 static
1149 bt_component_class_message_iterator_init_method_status
1150 muxer_msg_iter_init_upstream_iterators(struct muxer_comp *muxer_comp,
1151                 struct muxer_msg_iter *muxer_msg_iter)
1152 {
1153         int64_t count;
1154         int64_t i;
1155         bt_component_class_message_iterator_init_method_status status;
1156
1157         count = bt_component_filter_get_input_port_count(
1158                 bt_self_component_filter_as_component_filter(
1159                         muxer_comp->self_comp_flt));
1160         if (count < 0) {
1161                 BT_COMP_LOGD("No input port to initialize for muxer component's message iterator: "
1162                         "muxer-comp-addr=%p, muxer-msg-iter-addr=%p",
1163                         muxer_comp, muxer_msg_iter);
1164                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_INIT_METHOD_STATUS_OK;
1165                 goto end;
1166         }
1167
1168         for (i = 0; i < count; i++) {
1169                 bt_self_component_port_input_message_iterator *upstream_msg_iter;
1170                 bt_self_component_port_input *self_port =
1171                         bt_self_component_filter_borrow_input_port_by_index(
1172                                 muxer_comp->self_comp_flt, i);
1173                 const bt_port *port;
1174                 bt_self_component_port_input_message_iterator_create_from_message_iterator_status
1175                         msg_iter_status;
1176                 int int_status;
1177
1178                 BT_ASSERT(self_port);
1179                 port = bt_self_component_port_as_port(
1180                         bt_self_component_port_input_as_self_component_port(
1181                                 self_port));
1182                 BT_ASSERT(port);
1183
1184                 if (!bt_port_is_connected(port)) {
1185                         /* Skip non-connected port */
1186                         continue;
1187                 }
1188
1189                 msg_iter_status = create_msg_iter_on_input_port(muxer_comp,
1190                         muxer_msg_iter, self_port, &upstream_msg_iter);
1191                 if (msg_iter_status != BT_SELF_COMPONENT_PORT_INPUT_MESSAGE_ITERATOR_CREATE_FROM_MESSAGE_ITERATOR_STATUS_OK) {
1192                         /* create_msg_iter_on_input_port() logs errors */
1193                         status = (int) msg_iter_status;
1194                         goto end;
1195                 }
1196
1197                 int_status = muxer_msg_iter_add_upstream_msg_iter(muxer_msg_iter,
1198                         upstream_msg_iter);
1199                 bt_self_component_port_input_message_iterator_put_ref(
1200                         upstream_msg_iter);
1201                 if (int_status) {
1202                         status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_INIT_METHOD_STATUS_ERROR;
1203                         /* muxer_msg_iter_add_upstream_msg_iter() logs errors */
1204                         goto end;
1205                 }
1206         }
1207
1208         status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_INIT_METHOD_STATUS_OK;
1209
1210 end:
1211         return status;
1212 }
1213
1214 BT_HIDDEN
1215 bt_component_class_message_iterator_init_method_status muxer_msg_iter_init(
1216                 bt_self_message_iterator *self_msg_iter,
1217                 bt_self_component_filter *self_comp,
1218                 bt_self_component_port_output *port)
1219 {
1220         struct muxer_comp *muxer_comp = NULL;
1221         struct muxer_msg_iter *muxer_msg_iter = NULL;
1222         bt_component_class_message_iterator_init_method_status status;
1223
1224         muxer_comp = bt_self_component_get_data(
1225                 bt_self_component_filter_as_self_component(self_comp));
1226         BT_ASSERT(muxer_comp);
1227         BT_COMP_LOGD("Initializing muxer component's message iterator: "
1228                 "comp-addr=%p, muxer-comp-addr=%p, msg-iter-addr=%p",
1229                 self_comp, muxer_comp, self_msg_iter);
1230
1231         if (muxer_comp->initializing_muxer_msg_iter) {
1232                 /*
1233                  * Weird, unhandled situation detected: downstream
1234                  * creates a muxer message iterator while creating
1235                  * another muxer message iterator (same component).
1236                  */
1237                 BT_COMP_LOGE("Recursive initialization of muxer component's message iterator: "
1238                         "comp-addr=%p, muxer-comp-addr=%p, msg-iter-addr=%p",
1239                         self_comp, muxer_comp, self_msg_iter);
1240                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_INIT_METHOD_STATUS_ERROR;
1241                 goto error;
1242         }
1243
1244         muxer_comp->initializing_muxer_msg_iter = true;
1245         muxer_msg_iter = g_new0(struct muxer_msg_iter, 1);
1246         if (!muxer_msg_iter) {
1247                 BT_COMP_LOGE_STR("Failed to allocate one muxer component's message iterator.");
1248                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_INIT_METHOD_STATUS_MEMORY_ERROR;
1249                 goto error;
1250         }
1251
1252         muxer_msg_iter->muxer_comp = muxer_comp;
1253         muxer_msg_iter->self_msg_iter = self_msg_iter;
1254         muxer_msg_iter->last_returned_ts_ns = INT64_MIN;
1255         muxer_msg_iter->active_muxer_upstream_msg_iters =
1256                 g_ptr_array_new_with_free_func(
1257                         (GDestroyNotify) destroy_muxer_upstream_msg_iter);
1258         if (!muxer_msg_iter->active_muxer_upstream_msg_iters) {
1259                 BT_COMP_LOGE_STR("Failed to allocate a GPtrArray.");
1260                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_INIT_METHOD_STATUS_MEMORY_ERROR;
1261                 goto error;
1262         }
1263
1264         muxer_msg_iter->ended_muxer_upstream_msg_iters =
1265                 g_ptr_array_new_with_free_func(
1266                         (GDestroyNotify) destroy_muxer_upstream_msg_iter);
1267         if (!muxer_msg_iter->ended_muxer_upstream_msg_iters) {
1268                 BT_COMP_LOGE_STR("Failed to allocate a GPtrArray.");
1269                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_INIT_METHOD_STATUS_MEMORY_ERROR;
1270                 goto error;
1271         }
1272
1273         status = muxer_msg_iter_init_upstream_iterators(muxer_comp,
1274                 muxer_msg_iter);
1275         if (status) {
1276                 BT_COMP_LOGE("Cannot initialize connected input ports for muxer component's message iterator: "
1277                         "comp-addr=%p, muxer-comp-addr=%p, "
1278                         "muxer-msg-iter-addr=%p, msg-iter-addr=%p, ret=%d",
1279                         self_comp, muxer_comp, muxer_msg_iter,
1280                         self_msg_iter, status);
1281                 goto error;
1282         }
1283
1284         bt_self_message_iterator_set_data(self_msg_iter, muxer_msg_iter);
1285         BT_COMP_LOGD("Initialized muxer component's message iterator: "
1286                 "comp-addr=%p, muxer-comp-addr=%p, muxer-msg-iter-addr=%p, "
1287                 "msg-iter-addr=%p",
1288                 self_comp, muxer_comp, muxer_msg_iter, self_msg_iter);
1289         goto end;
1290
1291 error:
1292         destroy_muxer_msg_iter(muxer_msg_iter);
1293         bt_self_message_iterator_set_data(self_msg_iter, NULL);
1294
1295 end:
1296         muxer_comp->initializing_muxer_msg_iter = false;
1297         return status;
1298 }
1299
1300 BT_HIDDEN
1301 void muxer_msg_iter_finalize(bt_self_message_iterator *self_msg_iter)
1302 {
1303         struct muxer_msg_iter *muxer_msg_iter =
1304                 bt_self_message_iterator_get_data(self_msg_iter);
1305         bt_self_component *self_comp = NULL;
1306         struct muxer_comp *muxer_comp = NULL;
1307
1308         self_comp = bt_self_message_iterator_borrow_component(
1309                 self_msg_iter);
1310         BT_ASSERT(self_comp);
1311         muxer_comp = bt_self_component_get_data(self_comp);
1312         BT_COMP_LOGD("Finalizing muxer component's message iterator: "
1313                 "comp-addr=%p, muxer-comp-addr=%p, muxer-msg-iter-addr=%p, "
1314                 "msg-iter-addr=%p",
1315                 self_comp, muxer_comp, muxer_msg_iter, self_msg_iter);
1316
1317         if (muxer_msg_iter) {
1318                 destroy_muxer_msg_iter(muxer_msg_iter);
1319         }
1320 }
1321
1322 BT_HIDDEN
1323 bt_component_class_message_iterator_next_method_status muxer_msg_iter_next(
1324                 bt_self_message_iterator *self_msg_iter,
1325                 bt_message_array_const msgs, uint64_t capacity,
1326                 uint64_t *count)
1327 {
1328         bt_component_class_message_iterator_next_method_status status;
1329         struct muxer_msg_iter *muxer_msg_iter =
1330                 bt_self_message_iterator_get_data(self_msg_iter);
1331         bt_self_component *self_comp = NULL;
1332         struct muxer_comp *muxer_comp = NULL;
1333
1334         BT_ASSERT(muxer_msg_iter);
1335         self_comp = bt_self_message_iterator_borrow_component(
1336                 self_msg_iter);
1337         BT_ASSERT(self_comp);
1338         muxer_comp = bt_self_component_get_data(self_comp);
1339         BT_ASSERT(muxer_comp);
1340         BT_COMP_LOGT("Muxer component's message iterator's \"next\" method called: "
1341                 "comp-addr=%p, muxer-comp-addr=%p, muxer-msg-iter-addr=%p, "
1342                 "msg-iter-addr=%p",
1343                 self_comp, muxer_comp, muxer_msg_iter, self_msg_iter);
1344
1345         status = muxer_msg_iter_do_next(muxer_comp, muxer_msg_iter,
1346                 msgs, capacity, count);
1347         if (status < 0) {
1348                 BT_COMP_LOGE("Cannot get next message: "
1349                         "comp-addr=%p, muxer-comp-addr=%p, muxer-msg-iter-addr=%p, "
1350                         "msg-iter-addr=%p, status=%s",
1351                         self_comp, muxer_comp, muxer_msg_iter, self_msg_iter,
1352                         bt_common_func_status_string(status));
1353         } else {
1354                 BT_COMP_LOGT("Returning from muxer component's message iterator's \"next\" method: "
1355                         "status=%s",
1356                         bt_common_func_status_string(status));
1357         }
1358
1359         return status;
1360 }
1361
1362 BT_HIDDEN
1363 bt_component_class_port_connected_method_status muxer_input_port_connected(
1364                 bt_self_component_filter *self_comp,
1365                 bt_self_component_port_input *self_port,
1366                 const bt_port_output *other_port)
1367 {
1368         bt_component_class_port_connected_method_status status =
1369                 BT_COMPONENT_CLASS_PORT_CONNECTED_METHOD_STATUS_OK;
1370         bt_self_component_add_port_status add_port_status;
1371         struct muxer_comp *muxer_comp = bt_self_component_get_data(
1372                 bt_self_component_filter_as_self_component(self_comp));
1373
1374         add_port_status = add_available_input_port(self_comp);
1375         if (add_port_status) {
1376                 BT_COMP_LOGE("Cannot add one muxer component's input port: "
1377                         "status=%s",
1378                         bt_common_func_status_string(status));
1379
1380                 if (add_port_status ==
1381                                 BT_SELF_COMPONENT_ADD_PORT_STATUS_MEMORY_ERROR) {
1382                         status = BT_COMPONENT_CLASS_PORT_CONNECTED_METHOD_STATUS_MEMORY_ERROR;
1383                 } else {
1384                         status = BT_COMPONENT_CLASS_PORT_CONNECTED_METHOD_STATUS_ERROR;
1385                 }
1386
1387                 goto end;
1388         }
1389
1390 end:
1391         return status;
1392 }
1393
1394 static inline
1395 bt_component_class_message_iterator_can_seek_beginning_method_status
1396 muxer_upstream_msg_iters_can_all_seek_beginning(
1397                 GPtrArray *muxer_upstream_msg_iters, bt_bool *can_seek)
1398 {
1399         bt_component_class_message_iterator_can_seek_beginning_method_status status =
1400                 BT_COMPONENT_CLASS_MESSAGE_ITERATOR_CAN_SEEK_BEGINNING_METHOD_STATUS_OK;
1401         uint64_t i;
1402
1403         for (i = 0; i < muxer_upstream_msg_iters->len; i++) {
1404                 struct muxer_upstream_msg_iter *upstream_msg_iter =
1405                         muxer_upstream_msg_iters->pdata[i];
1406                 status = (int) bt_self_component_port_input_message_iterator_can_seek_beginning(
1407                         upstream_msg_iter->msg_iter, can_seek);
1408                 if (status != BT_COMPONENT_CLASS_MESSAGE_ITERATOR_CAN_SEEK_BEGINNING_METHOD_STATUS_OK) {
1409                         goto end;
1410                 }
1411
1412                 if (!*can_seek) {
1413                         goto end;
1414                 }
1415         }
1416
1417         *can_seek = BT_TRUE;
1418
1419 end:
1420         return status;
1421 }
1422
1423 BT_HIDDEN
1424 bt_component_class_message_iterator_can_seek_beginning_method_status
1425 muxer_msg_iter_can_seek_beginning(
1426                 bt_self_message_iterator *self_msg_iter, bt_bool *can_seek)
1427 {
1428         struct muxer_msg_iter *muxer_msg_iter =
1429                 bt_self_message_iterator_get_data(self_msg_iter);
1430         bt_component_class_message_iterator_can_seek_beginning_method_status status;
1431
1432         status = muxer_upstream_msg_iters_can_all_seek_beginning(
1433                 muxer_msg_iter->active_muxer_upstream_msg_iters, can_seek);
1434         if (status != BT_COMPONENT_CLASS_MESSAGE_ITERATOR_CAN_SEEK_BEGINNING_METHOD_STATUS_OK) {
1435                 goto end;
1436         }
1437
1438         if (!*can_seek) {
1439                 goto end;
1440         }
1441
1442         status = muxer_upstream_msg_iters_can_all_seek_beginning(
1443                 muxer_msg_iter->ended_muxer_upstream_msg_iters, can_seek);
1444
1445 end:
1446         return status;
1447 }
1448
1449 BT_HIDDEN
1450 bt_component_class_message_iterator_seek_beginning_method_status muxer_msg_iter_seek_beginning(
1451                 bt_self_message_iterator *self_msg_iter)
1452 {
1453         struct muxer_msg_iter *muxer_msg_iter =
1454                 bt_self_message_iterator_get_data(self_msg_iter);
1455         bt_component_class_message_iterator_seek_beginning_method_status status =
1456                 BT_COMPONENT_CLASS_MESSAGE_ITERATOR_SEEK_BEGINNING_METHOD_STATUS_OK;
1457         bt_message_iterator_seek_beginning_status seek_beg_status;
1458         uint64_t i;
1459
1460         /* Seek all ended upstream iterators first */
1461         for (i = 0; i < muxer_msg_iter->ended_muxer_upstream_msg_iters->len;
1462                         i++) {
1463                 struct muxer_upstream_msg_iter *upstream_msg_iter =
1464                         muxer_msg_iter->ended_muxer_upstream_msg_iters->pdata[i];
1465
1466                 seek_beg_status = bt_self_component_port_input_message_iterator_seek_beginning(
1467                         upstream_msg_iter->msg_iter);
1468                 if (seek_beg_status != BT_MESSAGE_ITERATOR_SEEK_BEGINNING_STATUS_OK) {
1469                         status = (int) seek_beg_status;
1470                         goto end;
1471                 }
1472
1473                 empty_message_queue(upstream_msg_iter);
1474         }
1475
1476         /* Seek all previously active upstream iterators */
1477         for (i = 0; i < muxer_msg_iter->active_muxer_upstream_msg_iters->len;
1478                         i++) {
1479                 struct muxer_upstream_msg_iter *upstream_msg_iter =
1480                         muxer_msg_iter->active_muxer_upstream_msg_iters->pdata[i];
1481
1482                 seek_beg_status = bt_self_component_port_input_message_iterator_seek_beginning(
1483                         upstream_msg_iter->msg_iter);
1484                 if (seek_beg_status != BT_MESSAGE_ITERATOR_SEEK_BEGINNING_STATUS_OK) {
1485                         status = (int) seek_beg_status;
1486                         goto end;
1487                 }
1488
1489                 empty_message_queue(upstream_msg_iter);
1490         }
1491
1492         /* Make them all active */
1493         for (i = 0; i < muxer_msg_iter->ended_muxer_upstream_msg_iters->len;
1494                         i++) {
1495                 struct muxer_upstream_msg_iter *upstream_msg_iter =
1496                         muxer_msg_iter->ended_muxer_upstream_msg_iters->pdata[i];
1497
1498                 g_ptr_array_add(muxer_msg_iter->active_muxer_upstream_msg_iters,
1499                         upstream_msg_iter);
1500                 muxer_msg_iter->ended_muxer_upstream_msg_iters->pdata[i] = NULL;
1501         }
1502
1503         /*
1504          * GLib < 2.48.0 asserts when g_ptr_array_remove_range() is
1505          * called on an empty array.
1506          */
1507         if (muxer_msg_iter->ended_muxer_upstream_msg_iters->len > 0) {
1508                 g_ptr_array_remove_range(muxer_msg_iter->ended_muxer_upstream_msg_iters,
1509                         0, muxer_msg_iter->ended_muxer_upstream_msg_iters->len);
1510         }
1511         muxer_msg_iter->last_returned_ts_ns = INT64_MIN;
1512         muxer_msg_iter->clock_class_expectation =
1513                 MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_ANY;
1514
1515 end:
1516         return status;
1517 }