src/plugins/utils/muxer/muxer.c

   1 /*
   2  * SPDX-License-Identifier: MIT
   3  *
   4  * Copyright 2017 Philippe Proulx <pproulx@efficios.com>
   5  */
   6
   7 #define BT_COMP_LOG_SELF_COMP (muxer_comp->self_comp)
   8 #define BT_LOG_OUTPUT_LEVEL (muxer_comp->log_level)
   9 #define BT_LOG_TAG "PLUGIN/FLT.UTILS.MUXER"
  10 #include "logging/comp-logging.h"
  11
  12 #include "common/macros.h"
  13 #include "common/uuid.h"
  14 #include <babeltrace2/babeltrace.h>
  15 #include <glib.h>
  16 #include <stdbool.h>
  17 #include <inttypes.h>
  18 #include "common/assert.h"
  19 #include "common/common.h"
  20 #include <stdlib.h>
  21 #include <string.h>
  22
  23 #include "plugins/common/muxing/muxing.h"
  24 #include "plugins/common/param-validation/param-validation.h"
  25
  26 #include "muxer.h"
  27
  28 struct muxer_comp {
  29         /* Weak refs */
  30         bt_self_component_filter *self_comp_flt;
  31         bt_self_component *self_comp;
  32
  33         unsigned int next_port_num;
  34         size_t available_input_ports;
  35         bool initializing_muxer_msg_iter;
  36         bt_logging_level log_level;
  37 };
  38
  39 struct muxer_upstream_msg_iter {
  40         struct muxer_comp *muxer_comp;
  41
  42         /* Owned by this, NULL if ended */
  43         bt_message_iterator *msg_iter;
  44
  45         /* Contains `const bt_message *`, owned by this */
  46         GPtrArray *msgs;
  47
  48         /* Index of the next message in `msgs` to return */
  49         guint next_msg;
  50 };
  51
  52 enum muxer_msg_iter_clock_class_expectation {
  53         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_ANY = 0,
  54         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NONE,
  55         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_ABSOLUTE,
  56         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NOT_ABS_SPEC_UUID,
  57         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NOT_ABS_NO_UUID,
  58 };
  59
  60 struct muxer_msg_iter {
  61         struct muxer_comp *muxer_comp;
  62
  63         /* Weak */
  64         bt_self_message_iterator *self_msg_iter;
  65
  66         /*
  67          * Array of struct muxer_upstream_msg_iter * (owned by this).
  68          *
  69          * NOTE: This array is searched in linearly to find the youngest
  70          * current message. Keep this until benchmarks confirm that
  71          * another data structure is faster than this for our typical
  72          * use cases.
  73          */
  74         GPtrArray *active_muxer_upstream_msg_iters;
  75
  76         /*
  77          * Array of struct muxer_upstream_msg_iter * (owned by this).
  78          *
  79          * We move ended message iterators from
  80          * `active_muxer_upstream_msg_iters` to this array so as to be
  81          * able to restore them when seeking.
  82          */
  83         GPtrArray *ended_muxer_upstream_msg_iters;
  84
  85         /* Last time returned in a message */
  86         int64_t last_returned_ts_ns;
  87
  88         /* Clock class expectation state */
  89         enum muxer_msg_iter_clock_class_expectation clock_class_expectation;
  90
  91         /*
  92          * Expected clock class UUID, only valid when
  93          * clock_class_expectation is
  94          * MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NOT_ABS_SPEC_UUID.
  95          */
  96         bt_uuid_t expected_clock_class_uuid;
  97
  98         /*
  99          * Saved error.  If we hit an error in the _next method, but have some
 100          * messages ready to return, we save the error here and return it on
 101          * the next _next call.
 102          */
 103         bt_message_iterator_class_next_method_status next_saved_status;
 104         const struct bt_error *next_saved_error;
 105 };
 106
 107 static
 108 void empty_message_queue(struct muxer_upstream_msg_iter *upstream_msg_iter)
 109 {
 110         g_ptr_array_set_size(upstream_msg_iter->msgs, 0);
 111 }
 112
 113 static
 114 void destroy_muxer_upstream_msg_iter(
 115                 struct muxer_upstream_msg_iter *muxer_upstream_msg_iter)
 116 {
 117         struct muxer_comp *muxer_comp;
 118
 119         if (!muxer_upstream_msg_iter) {
 120                 return;
 121         }
 122
 123         muxer_comp = muxer_upstream_msg_iter->muxer_comp;
 124         BT_COMP_LOGD("Destroying muxer's upstream message iterator wrapper: "
 125                 "addr=%p, msg-iter-addr=%p, queue-len=%u, next-msg=%u",
 126                 muxer_upstream_msg_iter,
 127                 muxer_upstream_msg_iter->msg_iter,
 128                 muxer_upstream_msg_iter->msgs->len,
 129                 muxer_upstream_msg_iter->next_msg);
 130
 131         bt_message_iterator_put_ref(
 132                 muxer_upstream_msg_iter->msg_iter);
 133
 134         if (muxer_upstream_msg_iter->msgs) {
 135                 g_ptr_array_free(muxer_upstream_msg_iter->msgs, TRUE);
 136         }
 137
 138         g_free(muxer_upstream_msg_iter);
 139 }
 140
 141 static
 142 int muxer_msg_iter_add_upstream_msg_iter(struct muxer_msg_iter *muxer_msg_iter,
 143                 bt_message_iterator *self_msg_iter)
 144 {
 145         int ret = 0;
 146         struct muxer_upstream_msg_iter *muxer_upstream_msg_iter =
 147                 g_new0(struct muxer_upstream_msg_iter, 1);
 148         struct muxer_comp *muxer_comp = muxer_msg_iter->muxer_comp;
 149
 150         if (!muxer_upstream_msg_iter) {
 151                 BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
 152                         "Failed to allocate one muxer's upstream message iterator wrapper.");
 153                 goto error;
 154         }
 155
 156         muxer_upstream_msg_iter->muxer_comp = muxer_comp;
 157         muxer_upstream_msg_iter->msg_iter = self_msg_iter;
 158         bt_message_iterator_get_ref(muxer_upstream_msg_iter->msg_iter);
 159         muxer_upstream_msg_iter->msgs =
 160                 g_ptr_array_new_with_free_func((GDestroyNotify) bt_message_put_ref);
 161         if (!muxer_upstream_msg_iter->msgs) {
 162                 BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
 163                         "Failed to allocate a GPtrArray.");
 164                 goto error;
 165         }
 166
 167         g_ptr_array_add(muxer_msg_iter->active_muxer_upstream_msg_iters,
 168                 muxer_upstream_msg_iter);
 169         BT_COMP_LOGD("Added muxer's upstream message iterator wrapper: "
 170                 "addr=%p, muxer-msg-iter-addr=%p, msg-iter-addr=%p",
 171                 muxer_upstream_msg_iter, muxer_msg_iter,
 172                 self_msg_iter);
 173
 174         goto end;
 175
 176 error:
 177         destroy_muxer_upstream_msg_iter(muxer_upstream_msg_iter);
 178         ret = -1;
 179
 180 end:
 181         return ret;
 182 }
 183
 184 static
 185 bt_self_component_add_port_status add_available_input_port(
 186                 bt_self_component_filter *self_comp)
 187 {
 188         struct muxer_comp *muxer_comp = bt_self_component_get_data(
 189                 bt_self_component_filter_as_self_component(self_comp));
 190         bt_self_component_add_port_status status =
 191                 BT_SELF_COMPONENT_ADD_PORT_STATUS_OK;
 192         GString *port_name = NULL;
 193
 194         BT_ASSERT(muxer_comp);
 195         port_name = g_string_new("in");
 196         if (!port_name) {
 197                 BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp, "Failed to allocate a GString.");
 198                 status = BT_SELF_COMPONENT_ADD_PORT_STATUS_MEMORY_ERROR;
 199                 goto end;
 200         }
 201
 202         g_string_append_printf(port_name, "%u", muxer_comp->next_port_num);
 203         status = bt_self_component_filter_add_input_port(
 204                 self_comp, port_name->str, NULL, NULL);
 205         if (status != BT_SELF_COMPONENT_ADD_PORT_STATUS_OK) {
 206                 BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
 207                         "Cannot add input port to muxer component: "
 208                         "port-name=\"%s\", comp-addr=%p, status=%s",
 209                         port_name->str, self_comp,
 210                         bt_common_func_status_string(status));
 211                 goto end;
 212         }
 213
 214         muxer_comp->available_input_ports++;
 215         muxer_comp->next_port_num++;
 216         BT_COMP_LOGI("Added one input port to muxer component: "
 217                 "port-name=\"%s\", comp-addr=%p",
 218                 port_name->str, self_comp);
 219
 220 end:
 221         if (port_name) {
 222                 g_string_free(port_name, TRUE);
 223         }
 224
 225         return status;
 226 }
 227
 228 static
 229 bt_self_component_add_port_status create_output_port(
 230                 bt_self_component_filter *self_comp)
 231 {
 232         return bt_self_component_filter_add_output_port(
 233                 self_comp, "out", NULL, NULL);
 234 }
 235
 236 static
 237 void destroy_muxer_comp(struct muxer_comp *muxer_comp)
 238 {
 239         if (!muxer_comp) {
 240                 return;
 241         }
 242
 243         g_free(muxer_comp);
 244 }
 245
 246 static
 247 struct bt_param_validation_map_value_entry_descr muxer_params[] = {
 248         BT_PARAM_VALIDATION_MAP_VALUE_ENTRY_END
 249 };
 250
 251 BT_HIDDEN
 252 bt_component_class_initialize_method_status muxer_init(
 253                 bt_self_component_filter *self_comp_flt,
 254                 bt_self_component_filter_configuration *config,
 255                 const bt_value *params, void *init_data)
 256 {
 257         bt_component_class_initialize_method_status status;
 258         bt_self_component_add_port_status add_port_status;
 259         bt_self_component *self_comp =
 260                 bt_self_component_filter_as_self_component(self_comp_flt);
 261         struct muxer_comp *muxer_comp = g_new0(struct muxer_comp, 1);
 262         bt_logging_level log_level = bt_component_get_logging_level(
 263                 bt_self_component_as_component(self_comp));
 264         enum bt_param_validation_status validation_status;
 265         gchar *validate_error = NULL;
 266
 267         BT_COMP_LOG_CUR_LVL(BT_LOG_INFO, log_level, self_comp,
 268                 "Initializing muxer component: "
 269                 "comp-addr=%p, params-addr=%p", self_comp, params);
 270
 271         if (!muxer_comp) {
 272                 /*
 273                  * Don't use BT_COMP_LOGE_APPEND_CAUSE, as `muxer_comp` is not
 274                  * initialized.
 275                  */
 276                 BT_COMP_LOG_CUR_LVL(BT_LOG_ERROR, log_level, self_comp,
 277                         "Failed to allocate one muxer component.");
 278                 BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_COMPONENT(self_comp,
 279                         "Failed to allocate one muxer component.");
 280                         status = BT_COMPONENT_CLASS_INITIALIZE_METHOD_STATUS_MEMORY_ERROR;
 281                 goto error;
 282         }
 283
 284         muxer_comp->log_level = log_level;
 285         muxer_comp->self_comp = self_comp;
 286         muxer_comp->self_comp_flt = self_comp_flt;
 287
 288         validation_status = bt_param_validation_validate(params,
 289                 muxer_params, &validate_error);
 290         if (validation_status == BT_PARAM_VALIDATION_STATUS_MEMORY_ERROR) {
 291                 status = BT_COMPONENT_CLASS_INITIALIZE_METHOD_STATUS_MEMORY_ERROR;
 292                 goto error;
 293         } else if (validation_status == BT_PARAM_VALIDATION_STATUS_VALIDATION_ERROR) {
 294                 status = BT_COMPONENT_CLASS_INITIALIZE_METHOD_STATUS_ERROR;
 295                 BT_COMP_LOGE_APPEND_CAUSE(self_comp, "%s", validate_error);
 296                 goto error;
 297         }
 298
 299         bt_self_component_set_data(self_comp, muxer_comp);
 300         add_port_status = add_available_input_port(self_comp_flt);
 301         if (add_port_status != BT_SELF_COMPONENT_ADD_PORT_STATUS_OK) {
 302                 BT_COMP_LOGE_APPEND_CAUSE(self_comp,
 303                         "Cannot ensure that at least one muxer component's input port is available: "
 304                         "muxer-comp-addr=%p, status=%s",
 305                         muxer_comp, bt_common_func_status_string(add_port_status));
 306                 status = (int) add_port_status;
 307                 goto error;
 308         }
 309
 310         add_port_status = create_output_port(self_comp_flt);
 311         if (add_port_status != BT_SELF_COMPONENT_ADD_PORT_STATUS_OK) {
 312                 BT_COMP_LOGE_APPEND_CAUSE(self_comp,
 313                         "Cannot create muxer component's output port: "
 314                         "muxer-comp-addr=%p, status=%s",
 315                         muxer_comp, bt_common_func_status_string(add_port_status));
 316                 status = (int) add_port_status;
 317                 goto error;
 318         }
 319
 320         BT_COMP_LOGI("Initialized muxer component: "
 321                 "comp-addr=%p, params-addr=%p, muxer-comp-addr=%p",
 322                 self_comp, params, muxer_comp);
 323
 324         status = BT_COMPONENT_CLASS_INITIALIZE_METHOD_STATUS_OK;
 325         goto end;
 326
 327 error:
 328         destroy_muxer_comp(muxer_comp);
 329         bt_self_component_set_data(self_comp, NULL);
 330
 331 end:
 332         g_free(validate_error);
 333         return status;
 334 }
 335
 336 BT_HIDDEN
 337 void muxer_finalize(bt_self_component_filter *self_comp)
 338 {
 339         struct muxer_comp *muxer_comp = bt_self_component_get_data(
 340                 bt_self_component_filter_as_self_component(self_comp));
 341
 342         BT_COMP_LOGI("Finalizing muxer component: comp-addr=%p",
 343                 self_comp);
 344         destroy_muxer_comp(muxer_comp);
 345 }
 346
 347 static
 348 bt_message_iterator_create_from_message_iterator_status
 349 create_msg_iter_on_input_port(struct muxer_comp *muxer_comp,
 350                 struct muxer_msg_iter *muxer_msg_iter,
 351                 bt_self_component_port_input *self_port,
 352                 bt_message_iterator **msg_iter)
 353 {
 354         const bt_port *port = bt_self_component_port_as_port(
 355                 bt_self_component_port_input_as_self_component_port(
 356                         self_port));
 357         bt_message_iterator_create_from_message_iterator_status
 358                 status;
 359
 360         BT_ASSERT(port);
 361         BT_ASSERT(bt_port_is_connected(port));
 362
 363         // TODO: Advance the iterator to >= the time of the latest
 364         //       returned message by the muxer message
 365         //       iterator which creates it.
 366         status = bt_message_iterator_create_from_message_iterator(
 367                 muxer_msg_iter->self_msg_iter, self_port, msg_iter);
 368         if (status != BT_MESSAGE_ITERATOR_CREATE_FROM_MESSAGE_ITERATOR_STATUS_OK) {
 369                 BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
 370                         "Cannot create upstream message iterator on input port: "
 371                         "port-addr=%p, port-name=\"%s\"",
 372                         port, bt_port_get_name(port));
 373                 goto end;
 374         }
 375
 376         BT_COMP_LOGI("Created upstream message iterator on input port: "
 377                 "port-addr=%p, port-name=\"%s\", msg-iter-addr=%p",
 378                 port, bt_port_get_name(port), msg_iter);
 379
 380 end:
 381         return status;
 382 }
 383
 384 static
 385 bt_message_iterator_class_next_method_status muxer_upstream_msg_iter_next(
 386                 struct muxer_upstream_msg_iter *muxer_upstream_msg_iter,
 387                 bool *is_ended)
 388 {
 389         struct muxer_comp *muxer_comp = muxer_upstream_msg_iter->muxer_comp;
 390         bt_message_iterator_class_next_method_status status;
 391         bt_message_iterator_next_status input_port_iter_status;
 392         bt_message_array_const msgs;
 393         uint64_t i;
 394         uint64_t count;
 395
 396         BT_COMP_LOGD("Calling upstream message iterator's \"next\" method: "
 397                 "muxer-upstream-msg-iter-wrap-addr=%p, msg-iter-addr=%p",
 398                 muxer_upstream_msg_iter,
 399                 muxer_upstream_msg_iter->msg_iter);
 400         input_port_iter_status = bt_message_iterator_next(
 401                 muxer_upstream_msg_iter->msg_iter, &msgs, &count);
 402         BT_COMP_LOGD("Upstream message iterator's \"next\" method returned: "
 403                 "status=%s",
 404                 bt_common_func_status_string(input_port_iter_status));
 405
 406         switch (input_port_iter_status) {
 407         case BT_MESSAGE_ITERATOR_NEXT_STATUS_OK:
 408                 /*
 409                  * Message iterator's current message is
 410                  * valid: it must be considered for muxing operations.
 411                  */
 412                 BT_COMP_LOGD_STR("Validated upstream message iterator wrapper.");
 413                 BT_ASSERT_DBG(count > 0);
 414
 415                 g_ptr_array_set_size(muxer_upstream_msg_iter->msgs, count);
 416                 muxer_upstream_msg_iter->next_msg = 0;
 417
 418                 /* Move messages to our queue */
 419                 for (i = 0; i < count; i++) {
 420                         /*
 421                          * Push to tail in order; other side
 422                          * (muxer_msg_iter_do_next_one()) consumes
 423                          * from the head first.
 424                          */
 425                         g_ptr_array_index(muxer_upstream_msg_iter->msgs, i)
 426                                 = (gpointer *) msgs[i];
 427                 }
 428                 status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_OK;
 429                 break;
 430         case BT_MESSAGE_ITERATOR_NEXT_STATUS_AGAIN:
 431                 /*
 432                  * Message iterator's current message is not
 433                  * valid anymore. Return
 434                  * BT_MESSAGE_ITERATOR_NEXT_STATUS_AGAIN immediately.
 435                  */
 436                 status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_AGAIN;
 437                 break;
 438         case BT_MESSAGE_ITERATOR_NEXT_STATUS_END:       /* Fall-through. */
 439                 /*
 440                  * Message iterator reached the end: release it. It
 441                  * won't be considered again to find the youngest
 442                  * message.
 443                  */
 444                 *is_ended = true;
 445                 status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_OK;
 446                 break;
 447         case BT_MESSAGE_ITERATOR_NEXT_STATUS_ERROR:
 448         case BT_MESSAGE_ITERATOR_NEXT_STATUS_MEMORY_ERROR:
 449                 /* Error status code */
 450                 BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
 451                         "Upstream iterator's next method returned an error: status=%s",
 452                         bt_common_func_status_string(input_port_iter_status));
 453                 status = (int) input_port_iter_status;
 454                 break;
 455         default:
 456                 /* Unsupported status code */
 457                 BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
 458                         "Unsupported status code: status=%s",
 459                         bt_common_func_status_string(input_port_iter_status));
 460                 status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_ERROR;
 461                 break;
 462         }
 463
 464         return status;
 465 }
 466
 467 static
 468 int get_msg_ts_ns(struct muxer_comp *muxer_comp,
 469                 struct muxer_msg_iter *muxer_msg_iter,
 470                 const bt_message *msg, int64_t last_returned_ts_ns,
 471                 int64_t *ts_ns)
 472 {
 473         const bt_clock_snapshot *clock_snapshot = NULL;
 474         int ret = 0;
 475         const bt_stream_class *stream_class = NULL;
 476         bt_message_type msg_type;
 477
 478         BT_ASSERT_DBG(msg);
 479         BT_ASSERT_DBG(ts_ns);
 480         BT_COMP_LOGD("Getting message's timestamp: "
 481                 "muxer-msg-iter-addr=%p, msg-addr=%p, "
 482                 "last-returned-ts=%" PRId64,
 483                 muxer_msg_iter, msg, last_returned_ts_ns);
 484
 485         if (G_UNLIKELY(muxer_msg_iter->clock_class_expectation ==
 486                         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NONE)) {
 487                 *ts_ns = last_returned_ts_ns;
 488                 goto end;
 489         }
 490
 491         msg_type = bt_message_get_type(msg);
 492
 493         if (G_UNLIKELY(msg_type == BT_MESSAGE_TYPE_PACKET_BEGINNING)) {
 494                 stream_class = bt_stream_borrow_class_const(
 495                         bt_packet_borrow_stream_const(
 496                                 bt_message_packet_beginning_borrow_packet_const(
 497                                         msg)));
 498         } else if (G_UNLIKELY(msg_type == BT_MESSAGE_TYPE_PACKET_END)) {
 499                 stream_class = bt_stream_borrow_class_const(
 500                         bt_packet_borrow_stream_const(
 501                                 bt_message_packet_end_borrow_packet_const(
 502                                         msg)));
 503         } else if (G_UNLIKELY(msg_type == BT_MESSAGE_TYPE_DISCARDED_EVENTS)) {
 504                 stream_class = bt_stream_borrow_class_const(
 505                         bt_message_discarded_events_borrow_stream_const(msg));
 506         } else if (G_UNLIKELY(msg_type == BT_MESSAGE_TYPE_DISCARDED_PACKETS)) {
 507                 stream_class = bt_stream_borrow_class_const(
 508                         bt_message_discarded_packets_borrow_stream_const(msg));
 509         }
 510
 511         switch (msg_type) {
 512         case BT_MESSAGE_TYPE_EVENT:
 513                 BT_ASSERT_DBG(bt_message_event_borrow_stream_class_default_clock_class_const(
 514                                 msg));
 515                 clock_snapshot = bt_message_event_borrow_default_clock_snapshot_const(
 516                         msg);
 517                 break;
 518         case BT_MESSAGE_TYPE_PACKET_BEGINNING:
 519                 if (bt_stream_class_packets_have_beginning_default_clock_snapshot(
 520                                 stream_class)) {
 521                         clock_snapshot = bt_message_packet_beginning_borrow_default_clock_snapshot_const(
 522                                 msg);
 523                 } else {
 524                         goto no_clock_snapshot;
 525                 }
 526
 527                 break;
 528         case BT_MESSAGE_TYPE_PACKET_END:
 529                 if (bt_stream_class_packets_have_end_default_clock_snapshot(
 530                                 stream_class)) {
 531                         clock_snapshot = bt_message_packet_end_borrow_default_clock_snapshot_const(
 532                                 msg);
 533                 } else {
 534                         goto no_clock_snapshot;
 535                 }
 536
 537                 break;
 538         case BT_MESSAGE_TYPE_STREAM_BEGINNING:
 539         {
 540                 enum bt_message_stream_clock_snapshot_state snapshot_state =
 541                         bt_message_stream_beginning_borrow_default_clock_snapshot_const(
 542                                 msg, &clock_snapshot);
 543                 if (snapshot_state == BT_MESSAGE_STREAM_CLOCK_SNAPSHOT_STATE_UNKNOWN) {
 544                         goto no_clock_snapshot;
 545                 }
 546
 547                 break;
 548         }
 549         case BT_MESSAGE_TYPE_STREAM_END:
 550         {
 551                 enum bt_message_stream_clock_snapshot_state snapshot_state =
 552                         bt_message_stream_end_borrow_default_clock_snapshot_const(
 553                                 msg, &clock_snapshot);
 554                 if (snapshot_state == BT_MESSAGE_STREAM_CLOCK_SNAPSHOT_STATE_UNKNOWN) {
 555                         goto no_clock_snapshot;
 556                 }
 557
 558                 break;
 559         }
 560         case BT_MESSAGE_TYPE_DISCARDED_EVENTS:
 561                 if (bt_stream_class_discarded_events_have_default_clock_snapshots(
 562                                 stream_class)) {
 563                         clock_snapshot = bt_message_discarded_events_borrow_beginning_default_clock_snapshot_const(
 564                                 msg);
 565                 } else {
 566                         goto no_clock_snapshot;
 567                 }
 568
 569                 break;
 570         case BT_MESSAGE_TYPE_DISCARDED_PACKETS:
 571                 if (bt_stream_class_discarded_packets_have_default_clock_snapshots(
 572                                 stream_class)) {
 573                         clock_snapshot = bt_message_discarded_packets_borrow_beginning_default_clock_snapshot_const(
 574                                 msg);
 575                 } else {
 576                         goto no_clock_snapshot;
 577                 }
 578
 579                 break;
 580         case BT_MESSAGE_TYPE_MESSAGE_ITERATOR_INACTIVITY:
 581                 clock_snapshot = bt_message_message_iterator_inactivity_borrow_clock_snapshot_const(
 582                         msg);
 583                 break;
 584         default:
 585                 /* All the other messages have a higher priority */
 586                 BT_COMP_LOGD_STR("Message has no timestamp: using the last returned timestamp.");
 587                 *ts_ns = last_returned_ts_ns;
 588                 goto end;
 589         }
 590
 591         ret = bt_clock_snapshot_get_ns_from_origin(clock_snapshot, ts_ns);
 592         if (ret) {
 593                 BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
 594                         "Cannot get nanoseconds from Epoch of clock snapshot: "
 595                         "clock-snapshot-addr=%p", clock_snapshot);
 596                 goto error;
 597         }
 598
 599         goto end;
 600
 601 no_clock_snapshot:
 602         BT_COMP_LOGD_STR("Message's default clock snapshot is missing: "
 603                 "using the last returned timestamp.");
 604         *ts_ns = last_returned_ts_ns;
 605         goto end;
 606
 607 error:
 608         ret = -1;
 609
 610 end:
 611         if (ret == 0) {
 612                 BT_COMP_LOGD("Found message's timestamp: "
 613                         "muxer-msg-iter-addr=%p, msg-addr=%p, "
 614                         "last-returned-ts=%" PRId64 ", ts=%" PRId64,
 615                         muxer_msg_iter, msg, last_returned_ts_ns,
 616                         *ts_ns);
 617         }
 618
 619         return ret;
 620 }
 621
 622 static inline
 623 int validate_clock_class(struct muxer_msg_iter *muxer_msg_iter,
 624                 struct muxer_comp *muxer_comp,
 625                 const bt_clock_class *clock_class)
 626 {
 627         int ret = 0;
 628         const uint8_t *cc_uuid;
 629         const char *cc_name;
 630
 631         BT_ASSERT_DBG(clock_class);
 632         cc_uuid = bt_clock_class_get_uuid(clock_class);
 633         cc_name = bt_clock_class_get_name(clock_class);
 634
 635         if (muxer_msg_iter->clock_class_expectation ==
 636                         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_ANY) {
 637                 /*
 638                  * This is the first clock class that this muxer message
 639                  * iterator encounters. Its properties determine what to expect
 640                  * for the whole lifetime of the iterator.
 641                  */
 642                 if (bt_clock_class_origin_is_unix_epoch(clock_class)) {
 643                         /* Expect absolute clock classes */
 644                         muxer_msg_iter->clock_class_expectation =
 645                                 MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_ABSOLUTE;
 646                 } else {
 647                         if (cc_uuid) {
 648                                 /*
 649                                  * Expect non-absolute clock classes
 650                                  * with a specific UUID.
 651                                  */
 652                                 muxer_msg_iter->clock_class_expectation =
 653                                         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NOT_ABS_SPEC_UUID;
 654                                 bt_uuid_copy(muxer_msg_iter->expected_clock_class_uuid, cc_uuid);
 655                         } else {
 656                                 /*
 657                                  * Expect non-absolute clock classes
 658                                  * with no UUID.
 659                                  */
 660                                 muxer_msg_iter->clock_class_expectation =
 661                                         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NOT_ABS_NO_UUID;
 662                         }
 663                 }
 664         }
 665
 666         switch (muxer_msg_iter->clock_class_expectation) {
 667         case MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_ABSOLUTE:
 668                 if (!bt_clock_class_origin_is_unix_epoch(clock_class)) {
 669                         BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
 670                                 "Expecting an absolute clock class, "
 671                                 "but got a non-absolute one: "
 672                                 "clock-class-addr=%p, clock-class-name=\"%s\"",
 673                                 clock_class, cc_name);
 674                         goto error;
 675                 }
 676                 break;
 677         case MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NOT_ABS_NO_UUID:
 678                 if (bt_clock_class_origin_is_unix_epoch(clock_class)) {
 679                         BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
 680                                 "Expecting a non-absolute clock class with no UUID, "
 681                                 "but got an absolute one: "
 682                                 "clock-class-addr=%p, clock-class-name=\"%s\"",
 683                                 clock_class, cc_name);
 684                         goto error;
 685                 }
 686
 687                 if (cc_uuid) {
 688                         BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
 689                                 "Expecting a non-absolute clock class with no UUID, "
 690                                 "but got one with a UUID: "
 691                                 "clock-class-addr=%p, clock-class-name=\"%s\", "
 692                                 "uuid=\"" BT_UUID_FMT "\"",
 693                                 clock_class, cc_name, BT_UUID_FMT_VALUES(cc_uuid));
 694                         goto error;
 695                 }
 696                 break;
 697         case MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NOT_ABS_SPEC_UUID:
 698                 if (bt_clock_class_origin_is_unix_epoch(clock_class)) {
 699                         BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
 700                                 "Expecting a non-absolute clock class with a specific UUID, "
 701                                 "but got an absolute one: "
 702                                 "clock-class-addr=%p, clock-class-name=\"%s\"",
 703                                 clock_class, cc_name);
 704                         goto error;
 705                 }
 706
 707                 if (!cc_uuid) {
 708                         BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
 709                                 "Expecting a non-absolute clock class with a specific UUID, "
 710                                 "but got one with no UUID: "
 711                                 "clock-class-addr=%p, clock-class-name=\"%s\"",
 712                                 clock_class, cc_name);
 713                         goto error;
 714                 }
 715
 716                 if (bt_uuid_compare(muxer_msg_iter->expected_clock_class_uuid, cc_uuid) != 0) {
 717                         BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
 718                                 "Expecting a non-absolute clock class with a specific UUID, "
 719                                 "but got one with different UUID: "
 720                                 "clock-class-addr=%p, clock-class-name=\"%s\", "
 721                                 "expected-uuid=\"" BT_UUID_FMT "\", "
 722                                 "uuid=\"" BT_UUID_FMT "\"",
 723                                 clock_class, cc_name,
 724                                 BT_UUID_FMT_VALUES(muxer_msg_iter->expected_clock_class_uuid),
 725                                 BT_UUID_FMT_VALUES(cc_uuid));
 726                         goto error;
 727                 }
 728                 break;
 729         case MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NONE:
 730                 BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
 731                         "Expecting no clock class, but got one: "
 732                         "clock-class-addr=%p, clock-class-name=\"%s\"",
 733                         clock_class, cc_name);
 734                 goto error;
 735         default:
 736                 /* Unexpected */
 737                 BT_COMP_LOGF("Unexpected clock class expectation: "
 738                         "expectation-code=%d",
 739                         muxer_msg_iter->clock_class_expectation);
 740                 bt_common_abort();
 741         }
 742
 743         goto end;
 744
 745 error:
 746         ret = -1;
 747
 748 end:
 749         return ret;
 750 }
 751
 752 static inline
 753 int validate_new_stream_clock_class(struct muxer_msg_iter *muxer_msg_iter,
 754                 struct muxer_comp *muxer_comp, const bt_stream *stream)
 755 {
 756         int ret = 0;
 757         const bt_stream_class *stream_class =
 758                 bt_stream_borrow_class_const(stream);
 759         const bt_clock_class *clock_class =
 760                 bt_stream_class_borrow_default_clock_class_const(stream_class);
 761
 762         if (!clock_class) {
 763                 if (muxer_msg_iter->clock_class_expectation ==
 764                         MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_ANY) {
 765                         /* Expect no clock class */
 766                         muxer_msg_iter->clock_class_expectation =
 767                                 MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NONE;
 768                 } else if (muxer_msg_iter->clock_class_expectation !=
 769                                 MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_NONE) {
 770                         BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
 771                                 "Expecting stream class without a default clock class: "
 772                                 "stream-class-addr=%p, stream-class-name=\"%s\", "
 773                                 "stream-class-id=%" PRIu64,
 774                                 stream_class, bt_stream_class_get_name(stream_class),
 775                                 bt_stream_class_get_id(stream_class));
 776                         ret = -1;
 777                 }
 778
 779                 goto end;
 780         }
 781
 782         ret = validate_clock_class(muxer_msg_iter, muxer_comp, clock_class);
 783
 784 end:
 785         return ret;
 786 }
 787
 788 /*
 789  * This function finds the youngest available message amongst the
 790  * non-ended upstream message iterators and returns the upstream
 791  * message iterator which has it, or
 792  * BT_MESSAGE_ITERATOR_STATUS_END if there's no available
 793  * message.
 794  *
 795  * This function does NOT:
 796  *
 797  * * Update any upstream message iterator.
 798  * * Check the upstream message iterators to retry.
 799  *
 800  * On sucess, this function sets *muxer_upstream_msg_iter to the
 801  * upstream message iterator of which the current message is
 802  * the youngest, and sets *ts_ns to its time.
 803  */
 804 static
 805 bt_message_iterator_class_next_method_status
 806 muxer_msg_iter_youngest_upstream_msg_iter(
 807                 struct muxer_comp *muxer_comp,
 808                 struct muxer_msg_iter *muxer_msg_iter,
 809                 struct muxer_upstream_msg_iter **muxer_upstream_msg_iter,
 810                 int64_t *ts_ns)
 811 {
 812         size_t i;
 813         int ret;
 814         int64_t youngest_ts_ns = INT64_MAX;
 815         bt_message_iterator_class_next_method_status status =
 816                 BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_OK;
 817
 818         BT_ASSERT_DBG(muxer_comp);
 819         BT_ASSERT_DBG(muxer_msg_iter);
 820         BT_ASSERT_DBG(muxer_upstream_msg_iter);
 821         *muxer_upstream_msg_iter = NULL;
 822
 823         for (i = 0; i < muxer_msg_iter->active_muxer_upstream_msg_iters->len;
 824                         i++) {
 825                 const bt_message *msg;
 826                 struct muxer_upstream_msg_iter *cur_muxer_upstream_msg_iter =
 827                         g_ptr_array_index(
 828                                 muxer_msg_iter->active_muxer_upstream_msg_iters,
 829                                 i);
 830                 int64_t msg_ts_ns;
 831
 832                 if (!cur_muxer_upstream_msg_iter->msg_iter) {
 833                         /* This upstream message iterator is ended */
 834                         BT_COMP_LOGT("Skipping ended upstream message iterator: "
 835                                 "muxer-upstream-msg-iter-wrap-addr=%p",
 836                                 cur_muxer_upstream_msg_iter);
 837                         continue;
 838                 }
 839
 840                 BT_ASSERT_DBG(cur_muxer_upstream_msg_iter->next_msg <
 841                         cur_muxer_upstream_msg_iter->msgs->len);
 842                 msg = g_ptr_array_index(cur_muxer_upstream_msg_iter->msgs,
 843                         cur_muxer_upstream_msg_iter->next_msg);
 844                 BT_ASSERT_DBG(msg);
 845
 846                 if (G_UNLIKELY(bt_message_get_type(msg) ==
 847                                 BT_MESSAGE_TYPE_STREAM_BEGINNING)) {
 848                         ret = validate_new_stream_clock_class(
 849                                 muxer_msg_iter, muxer_comp,
 850                                 bt_message_stream_beginning_borrow_stream_const(
 851                                         msg));
 852                         if (ret) {
 853                                 /*
 854                                  * validate_new_stream_clock_class() logs
 855                                  * errors.
 856                                  */
 857                                 status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_ERROR;
 858                                 goto end;
 859                         }
 860                 } else if (G_UNLIKELY(bt_message_get_type(msg) ==
 861                                 BT_MESSAGE_TYPE_MESSAGE_ITERATOR_INACTIVITY)) {
 862                         const bt_clock_snapshot *cs;
 863
 864                         cs = bt_message_message_iterator_inactivity_borrow_clock_snapshot_const(
 865                                 msg);
 866                         ret = validate_clock_class(muxer_msg_iter, muxer_comp,
 867                                 bt_clock_snapshot_borrow_clock_class_const(cs));
 868                         if (ret) {
 869                                 /* validate_clock_class() logs errors */
 870                                 status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_ERROR;
 871                                 goto end;
 872                         }
 873                 }
 874
 875                 ret = get_msg_ts_ns(muxer_comp, muxer_msg_iter, msg,
 876                         muxer_msg_iter->last_returned_ts_ns, &msg_ts_ns);
 877                 if (ret) {
 878                         /* get_msg_ts_ns() logs errors */
 879                         *muxer_upstream_msg_iter = NULL;
 880                         status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_ERROR;
 881                         goto end;
 882                 }
 883
 884                 /*
 885                  * Update the current message iterator if it has not been set
 886                  * yet, or if its current message has a timestamp smaller than
 887                  * the previously selected youngest message.
 888                  */
 889                 if (G_UNLIKELY(*muxer_upstream_msg_iter == NULL) ||
 890                                 msg_ts_ns < youngest_ts_ns) {
 891                         *muxer_upstream_msg_iter =
 892                                 cur_muxer_upstream_msg_iter;
 893                         youngest_ts_ns = msg_ts_ns;
 894                         *ts_ns = youngest_ts_ns;
 895                 } else if (msg_ts_ns == youngest_ts_ns) {
 896                         /*
 897                          * The currently selected message to be sent downstream
 898                          * next has the exact same timestamp that of the
 899                          * current candidate message. We must break the tie
 900                          * in a predictable manner.
 901                          */
 902                         BT_ASSERT_DBG((*muxer_upstream_msg_iter)->next_msg <
 903                                 (*muxer_upstream_msg_iter)->msgs->len);
 904                         const bt_message *selected_msg =
 905                                 g_ptr_array_index((*muxer_upstream_msg_iter)->msgs,
 906                                         (*muxer_upstream_msg_iter)->next_msg);
 907                         BT_COMP_LOGD_STR("Two of the next message candidates have the same timestamps, pick one deterministically.");
 908
 909                         /*
 910                          * Order the messages in an arbitrary but determinitic
 911                          * way.
 912                          */
 913                         ret = common_muxing_compare_messages(msg, selected_msg);
 914                         if (ret < 0) {
 915                                 /*
 916                                  * The `msg` should go first. Update the next
 917                                  * iterator and the current timestamp.
 918                                  */
 919                                 *muxer_upstream_msg_iter =
 920                                         cur_muxer_upstream_msg_iter;
 921                                 youngest_ts_ns = msg_ts_ns;
 922                                 *ts_ns = youngest_ts_ns;
 923                         } else if (ret == 0) {
 924                                 /* Unable to pick which one should go first. */
 925                                 BT_COMP_LOGW("Cannot deterministically pick next upstream message iterator because they have identical next messages: "
 926                                         "muxer-upstream-msg-iter-wrap-addr=%p"
 927                                         "cur-muxer-upstream-msg-iter-wrap-addr=%p",
 928                                         *muxer_upstream_msg_iter,
 929                                         cur_muxer_upstream_msg_iter);
 930                         }
 931                 }
 932         }
 933
 934         if (!*muxer_upstream_msg_iter) {
 935                 status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_END;
 936                 *ts_ns = INT64_MIN;
 937         }
 938
 939 end:
 940         return status;
 941 }
 942
 943 static
 944 bt_message_iterator_class_next_method_status
 945 validate_muxer_upstream_msg_iter(
 946         struct muxer_upstream_msg_iter *muxer_upstream_msg_iter,
 947         bool *is_ended)
 948 {
 949         struct muxer_comp *muxer_comp = muxer_upstream_msg_iter->muxer_comp;
 950         bt_message_iterator_class_next_method_status status;
 951
 952         BT_COMP_LOGD("Validating muxer's upstream message iterator wrapper: "
 953                 "muxer-upstream-msg-iter-wrap-addr=%p",
 954                 muxer_upstream_msg_iter);
 955
 956         if (muxer_upstream_msg_iter->next_msg < muxer_upstream_msg_iter->msgs->len ||
 957                         !muxer_upstream_msg_iter->msg_iter) {
 958                 BT_COMP_LOGD("Already valid or not considered: "
 959                         "queue-len=%u, next-msg=%u, upstream-msg-iter-addr=%p",
 960                         muxer_upstream_msg_iter->msgs->len,
 961                         muxer_upstream_msg_iter->next_msg,
 962                         muxer_upstream_msg_iter->msg_iter);
 963                 status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_OK;
 964                 goto end;
 965         }
 966
 967         /* muxer_upstream_msg_iter_next() logs details/errors */
 968         status = muxer_upstream_msg_iter_next(muxer_upstream_msg_iter,
 969                 is_ended);
 970
 971 end:
 972         return status;
 973 }
 974
 975 static
 976 bt_message_iterator_class_next_method_status
 977 validate_muxer_upstream_msg_iters(
 978                 struct muxer_msg_iter *muxer_msg_iter)
 979 {
 980         struct muxer_comp *muxer_comp = muxer_msg_iter->muxer_comp;
 981         bt_message_iterator_class_next_method_status status;
 982         size_t i;
 983
 984         BT_COMP_LOGD("Validating muxer's upstream message iterator wrappers: "
 985                 "muxer-msg-iter-addr=%p", muxer_msg_iter);
 986
 987         for (i = 0; i < muxer_msg_iter->active_muxer_upstream_msg_iters->len;
 988                         i++) {
 989                 bool is_ended = false;
 990                 struct muxer_upstream_msg_iter *muxer_upstream_msg_iter =
 991                         g_ptr_array_index(
 992                                 muxer_msg_iter->active_muxer_upstream_msg_iters,
 993                                 i);
 994
 995                 status = validate_muxer_upstream_msg_iter(
 996                         muxer_upstream_msg_iter, &is_ended);
 997                 if (status != BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_OK) {
 998                         if (status < 0) {
 999                                 BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
1000                                         "Cannot validate muxer's upstream message iterator wrapper: "
1001                                         "muxer-msg-iter-addr=%p, "
1002                                         "muxer-upstream-msg-iter-wrap-addr=%p",
1003                                         muxer_msg_iter,
1004                                         muxer_upstream_msg_iter);
1005                         } else {
1006                                 BT_COMP_LOGD("Cannot validate muxer's upstream message iterator wrapper: "
1007                                         "muxer-msg-iter-addr=%p, "
1008                                         "muxer-upstream-msg-iter-wrap-addr=%p",
1009                                         muxer_msg_iter,
1010                                         muxer_upstream_msg_iter);
1011                         }
1012
1013                         goto end;
1014                 }
1015
1016                 /*
1017                  * Move this muxer upstream message iterator to the
1018                  * array of ended iterators if it's ended.
1019                  */
1020                 if (G_UNLIKELY(is_ended)) {
1021                         BT_COMP_LOGD("Muxer's upstream message iterator wrapper: ended or canceled: "
1022                                 "muxer-msg-iter-addr=%p, "
1023                                 "muxer-upstream-msg-iter-wrap-addr=%p",
1024                                 muxer_msg_iter, muxer_upstream_msg_iter);
1025                         g_ptr_array_add(
1026                                 muxer_msg_iter->ended_muxer_upstream_msg_iters,
1027                                 muxer_upstream_msg_iter);
1028                         muxer_msg_iter->active_muxer_upstream_msg_iters->pdata[i] = NULL;
1029
1030                         /*
1031                          * Use g_ptr_array_remove_fast() because the
1032                          * order of those elements is not important.
1033                          */
1034                         g_ptr_array_remove_index_fast(
1035                                 muxer_msg_iter->active_muxer_upstream_msg_iters,
1036                                 i);
1037                         i--;
1038                 }
1039         }
1040
1041         status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_OK;
1042
1043 end:
1044         return status;
1045 }
1046
1047 static inline
1048 bt_message_iterator_class_next_method_status muxer_msg_iter_do_next_one(
1049                 struct muxer_comp *muxer_comp,
1050                 struct muxer_msg_iter *muxer_msg_iter,
1051                 const bt_message **msg)
1052 {
1053         bt_message_iterator_class_next_method_status status;
1054         struct muxer_upstream_msg_iter *muxer_upstream_msg_iter = NULL;
1055         /* Initialize to avoid -Wmaybe-uninitialized warning with gcc 4.8. */
1056         int64_t next_return_ts = 0;
1057
1058         status = validate_muxer_upstream_msg_iters(muxer_msg_iter);
1059         if (status != BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_OK) {
1060                 /* validate_muxer_upstream_msg_iters() logs details */
1061                 goto end;
1062         }
1063
1064         /*
1065          * At this point we know that all the existing upstream
1066          * message iterators are valid. We can find the one,
1067          * amongst those, of which the current message is the
1068          * youngest.
1069          */
1070         status = muxer_msg_iter_youngest_upstream_msg_iter(muxer_comp,
1071                         muxer_msg_iter, &muxer_upstream_msg_iter,
1072                         &next_return_ts);
1073         if (status < 0 || status == BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_END) {
1074                 if (status < 0) {
1075                         BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
1076                                 "Cannot find the youngest upstream message iterator wrapper: "
1077                                 "status=%s",
1078                                 bt_common_func_status_string(status));
1079                 } else {
1080                         BT_COMP_LOGD("Cannot find the youngest upstream message iterator wrapper: "
1081                                 "status=%s",
1082                                 bt_common_func_status_string(status));
1083                 }
1084
1085                 goto end;
1086         }
1087
1088         if (next_return_ts < muxer_msg_iter->last_returned_ts_ns) {
1089                 BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
1090                         "Youngest upstream message iterator wrapper's timestamp is less than muxer's message iterator's last returned timestamp: "
1091                         "muxer-msg-iter-addr=%p, ts=%" PRId64 ", "
1092                         "last-returned-ts=%" PRId64,
1093                         muxer_msg_iter, next_return_ts,
1094                         muxer_msg_iter->last_returned_ts_ns);
1095                 status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_ERROR;
1096                 goto end;
1097         }
1098
1099         BT_COMP_LOGD("Found youngest upstream message iterator wrapper: "
1100                 "muxer-msg-iter-addr=%p, "
1101                 "muxer-upstream-msg-iter-wrap-addr=%p, "
1102                 "ts=%" PRId64,
1103                 muxer_msg_iter, muxer_upstream_msg_iter, next_return_ts);
1104         BT_ASSERT_DBG(status ==
1105                 BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_OK);
1106         BT_ASSERT_DBG(muxer_upstream_msg_iter);
1107
1108         /*
1109          * Consume from the queue's head: other side
1110          * (muxer_upstream_msg_iter_next()) writes to the tail.
1111          */
1112         *msg = g_ptr_array_index(muxer_upstream_msg_iter->msgs,
1113                 muxer_upstream_msg_iter->next_msg);
1114         g_ptr_array_index(muxer_upstream_msg_iter->msgs,
1115                 muxer_upstream_msg_iter->next_msg) = NULL;
1116         ++muxer_upstream_msg_iter->next_msg;
1117         BT_ASSERT_DBG(*msg);
1118         muxer_msg_iter->last_returned_ts_ns = next_return_ts;
1119
1120 end:
1121         return status;
1122 }
1123
1124 static
1125 bt_message_iterator_class_next_method_status muxer_msg_iter_do_next(
1126                 struct muxer_comp *muxer_comp,
1127                 struct muxer_msg_iter *muxer_msg_iter,
1128                 bt_message_array_const msgs, uint64_t capacity,
1129                 uint64_t *count)
1130 {
1131         bt_message_iterator_class_next_method_status status;
1132         uint64_t i = 0;
1133
1134         if (G_UNLIKELY(muxer_msg_iter->next_saved_error)) {
1135                 /*
1136                  * Last time we were called, we hit an error but had some
1137                  * messages to deliver, so we stashed the error here.  Return
1138                  * it now.
1139                  */
1140                 BT_CURRENT_THREAD_MOVE_ERROR_AND_RESET(muxer_msg_iter->next_saved_error);
1141                 status = muxer_msg_iter->next_saved_status;
1142                 goto end;
1143         }
1144
1145         do {
1146                 status = muxer_msg_iter_do_next_one(muxer_comp,
1147                         muxer_msg_iter, &msgs[i]);
1148                 if (status == BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_OK) {
1149                         i++;
1150                 }
1151         } while (i < capacity && status == BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_OK);
1152
1153         if (i > 0) {
1154                 /*
1155                  * Even if muxer_msg_iter_do_next_one() returned
1156                  * something else than
1157                  * BT_MESSAGE_ITERATOR_STATUS_OK, we accumulated
1158                  * message objects in the output message
1159                  * array, so we need to return
1160                  * BT_MESSAGE_ITERATOR_STATUS_OK so that they are
1161                  * transfered to downstream. This other status occurs
1162                  * again the next time muxer_msg_iter_do_next() is
1163                  * called, possibly without any accumulated
1164                  * message, in which case we'll return it.
1165                  */
1166                 if (status < 0) {
1167                         /*
1168                          * Save this error for the next _next call.  Assume that
1169                          * this component always appends error causes when
1170                          * returning an error status code, which will cause the
1171                          * current thread error to be non-NULL.
1172                          */
1173                         muxer_msg_iter->next_saved_error = bt_current_thread_take_error();
1174                         BT_ASSERT(muxer_msg_iter->next_saved_error);
1175                         muxer_msg_iter->next_saved_status = status;
1176                 }
1177
1178                 *count = i;
1179                 status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_OK;
1180         }
1181
1182 end:
1183         return status;
1184 }
1185
1186 static
1187 void destroy_muxer_msg_iter(struct muxer_msg_iter *muxer_msg_iter)
1188 {
1189         struct muxer_comp *muxer_comp;
1190
1191         if (!muxer_msg_iter) {
1192                 return;
1193         }
1194
1195         muxer_comp = muxer_msg_iter->muxer_comp;
1196         BT_COMP_LOGD("Destroying muxer component's message iterator: "
1197                 "muxer-msg-iter-addr=%p", muxer_msg_iter);
1198
1199         if (muxer_msg_iter->active_muxer_upstream_msg_iters) {
1200                 BT_COMP_LOGD_STR("Destroying muxer's active upstream message iterator wrappers.");
1201                 g_ptr_array_free(
1202                         muxer_msg_iter->active_muxer_upstream_msg_iters, TRUE);
1203         }
1204
1205         if (muxer_msg_iter->ended_muxer_upstream_msg_iters) {
1206                 BT_COMP_LOGD_STR("Destroying muxer's ended upstream message iterator wrappers.");
1207                 g_ptr_array_free(
1208                         muxer_msg_iter->ended_muxer_upstream_msg_iters, TRUE);
1209         }
1210
1211         g_free(muxer_msg_iter);
1212 }
1213
1214 static
1215 bt_message_iterator_class_initialize_method_status
1216 muxer_msg_iter_init_upstream_iterators(struct muxer_comp *muxer_comp,
1217                 struct muxer_msg_iter *muxer_msg_iter,
1218                 struct bt_self_message_iterator_configuration *config)
1219 {
1220         int64_t count;
1221         int64_t i;
1222         bt_message_iterator_class_initialize_method_status status;
1223         bool can_seek_forward = true;
1224
1225         count = bt_component_filter_get_input_port_count(
1226                 bt_self_component_filter_as_component_filter(
1227                         muxer_comp->self_comp_flt));
1228         if (count < 0) {
1229                 BT_COMP_LOGD("No input port to initialize for muxer component's message iterator: "
1230                         "muxer-comp-addr=%p, muxer-msg-iter-addr=%p",
1231                         muxer_comp, muxer_msg_iter);
1232                 status = BT_MESSAGE_ITERATOR_CLASS_INITIALIZE_METHOD_STATUS_OK;
1233                 goto end;
1234         }
1235
1236         for (i = 0; i < count; i++) {
1237                 bt_message_iterator *upstream_msg_iter;
1238                 bt_self_component_port_input *self_port =
1239                         bt_self_component_filter_borrow_input_port_by_index(
1240                                 muxer_comp->self_comp_flt, i);
1241                 const bt_port *port;
1242                 bt_message_iterator_create_from_message_iterator_status
1243                         msg_iter_status;
1244                 int int_status;
1245
1246                 BT_ASSERT(self_port);
1247                 port = bt_self_component_port_as_port(
1248                         bt_self_component_port_input_as_self_component_port(
1249                                 self_port));
1250                 BT_ASSERT(port);
1251
1252                 if (!bt_port_is_connected(port)) {
1253                         /* Skip non-connected port */
1254                         continue;
1255                 }
1256
1257                 msg_iter_status = create_msg_iter_on_input_port(muxer_comp,
1258                         muxer_msg_iter, self_port, &upstream_msg_iter);
1259                 if (msg_iter_status != BT_MESSAGE_ITERATOR_CREATE_FROM_MESSAGE_ITERATOR_STATUS_OK) {
1260                         /* create_msg_iter_on_input_port() logs errors */
1261                         status = (int) msg_iter_status;
1262                         goto end;
1263                 }
1264
1265                 int_status = muxer_msg_iter_add_upstream_msg_iter(muxer_msg_iter,
1266                         upstream_msg_iter);
1267                 bt_message_iterator_put_ref(
1268                         upstream_msg_iter);
1269                 if (int_status) {
1270                         status = BT_MESSAGE_ITERATOR_CLASS_INITIALIZE_METHOD_STATUS_ERROR;
1271                         /* muxer_msg_iter_add_upstream_msg_iter() logs errors */
1272                         goto end;
1273                 }
1274
1275                 can_seek_forward = can_seek_forward &&
1276                         bt_message_iterator_can_seek_forward(
1277                                 upstream_msg_iter);
1278         }
1279
1280         /*
1281          * This iterator can seek forward if all of its iterators can seek
1282          * forward.
1283          */
1284         bt_self_message_iterator_configuration_set_can_seek_forward(
1285                 config, can_seek_forward);
1286
1287         status = BT_MESSAGE_ITERATOR_CLASS_INITIALIZE_METHOD_STATUS_OK;
1288
1289 end:
1290         return status;
1291 }
1292
1293 BT_HIDDEN
1294 bt_message_iterator_class_initialize_method_status muxer_msg_iter_init(
1295                 bt_self_message_iterator *self_msg_iter,
1296                 bt_self_message_iterator_configuration *config,
1297                 bt_self_component_port_output *port)
1298 {
1299         struct muxer_comp *muxer_comp = NULL;
1300         struct muxer_msg_iter *muxer_msg_iter = NULL;
1301         bt_message_iterator_class_initialize_method_status status;
1302         bt_self_component *self_comp =
1303                 bt_self_message_iterator_borrow_component(self_msg_iter);
1304
1305         muxer_comp = bt_self_component_get_data(self_comp);
1306         BT_ASSERT(muxer_comp);
1307         BT_COMP_LOGD("Initializing muxer component's message iterator: "
1308                 "comp-addr=%p, muxer-comp-addr=%p, msg-iter-addr=%p",
1309                 self_comp, muxer_comp, self_msg_iter);
1310
1311         if (muxer_comp->initializing_muxer_msg_iter) {
1312                 /*
1313                  * Weird, unhandled situation detected: downstream
1314                  * creates a muxer message iterator while creating
1315                  * another muxer message iterator (same component).
1316                  */
1317                 BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
1318                         "Recursive initialization of muxer component's message iterator: "
1319                         "comp-addr=%p, muxer-comp-addr=%p, msg-iter-addr=%p",
1320                         self_comp, muxer_comp, self_msg_iter);
1321                 status = BT_MESSAGE_ITERATOR_CLASS_INITIALIZE_METHOD_STATUS_ERROR;
1322                 goto error;
1323         }
1324
1325         muxer_comp->initializing_muxer_msg_iter = true;
1326         muxer_msg_iter = g_new0(struct muxer_msg_iter, 1);
1327         if (!muxer_msg_iter) {
1328                 BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
1329                         "Failed to allocate one muxer component's message iterator.");
1330                 status = BT_MESSAGE_ITERATOR_CLASS_INITIALIZE_METHOD_STATUS_MEMORY_ERROR;
1331                 goto error;
1332         }
1333
1334         muxer_msg_iter->muxer_comp = muxer_comp;
1335         muxer_msg_iter->self_msg_iter = self_msg_iter;
1336         muxer_msg_iter->last_returned_ts_ns = INT64_MIN;
1337         muxer_msg_iter->active_muxer_upstream_msg_iters =
1338                 g_ptr_array_new_with_free_func(
1339                         (GDestroyNotify) destroy_muxer_upstream_msg_iter);
1340         if (!muxer_msg_iter->active_muxer_upstream_msg_iters) {
1341                 BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp, "Failed to allocate a GPtrArray.");
1342                 status = BT_MESSAGE_ITERATOR_CLASS_INITIALIZE_METHOD_STATUS_MEMORY_ERROR;
1343                 goto error;
1344         }
1345
1346         muxer_msg_iter->ended_muxer_upstream_msg_iters =
1347                 g_ptr_array_new_with_free_func(
1348                         (GDestroyNotify) destroy_muxer_upstream_msg_iter);
1349         if (!muxer_msg_iter->ended_muxer_upstream_msg_iters) {
1350                 BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp, "Failed to allocate a GPtrArray.");
1351                 status = BT_MESSAGE_ITERATOR_CLASS_INITIALIZE_METHOD_STATUS_MEMORY_ERROR;
1352                 goto error;
1353         }
1354
1355         status = muxer_msg_iter_init_upstream_iterators(muxer_comp,
1356                 muxer_msg_iter, config);
1357         if (status) {
1358                 BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
1359                         "Cannot initialize connected input ports for muxer component's message iterator: "
1360                         "comp-addr=%p, muxer-comp-addr=%p, "
1361                         "muxer-msg-iter-addr=%p, msg-iter-addr=%p, ret=%d",
1362                         self_comp, muxer_comp, muxer_msg_iter,
1363                         self_msg_iter, status);
1364                 goto error;
1365         }
1366
1367         bt_self_message_iterator_set_data(self_msg_iter, muxer_msg_iter);
1368         BT_COMP_LOGD("Initialized muxer component's message iterator: "
1369                 "comp-addr=%p, muxer-comp-addr=%p, muxer-msg-iter-addr=%p, "
1370                 "msg-iter-addr=%p",
1371                 self_comp, muxer_comp, muxer_msg_iter, self_msg_iter);
1372         goto end;
1373
1374 error:
1375         destroy_muxer_msg_iter(muxer_msg_iter);
1376         bt_self_message_iterator_set_data(self_msg_iter, NULL);
1377
1378 end:
1379         muxer_comp->initializing_muxer_msg_iter = false;
1380         return status;
1381 }
1382
1383 BT_HIDDEN
1384 void muxer_msg_iter_finalize(bt_self_message_iterator *self_msg_iter)
1385 {
1386         struct muxer_msg_iter *muxer_msg_iter =
1387                 bt_self_message_iterator_get_data(self_msg_iter);
1388         bt_self_component *self_comp = NULL;
1389         struct muxer_comp *muxer_comp = NULL;
1390
1391         self_comp = bt_self_message_iterator_borrow_component(
1392                 self_msg_iter);
1393         BT_ASSERT(self_comp);
1394         muxer_comp = bt_self_component_get_data(self_comp);
1395         BT_COMP_LOGD("Finalizing muxer component's message iterator: "
1396                 "comp-addr=%p, muxer-comp-addr=%p, muxer-msg-iter-addr=%p, "
1397                 "msg-iter-addr=%p",
1398                 self_comp, muxer_comp, muxer_msg_iter, self_msg_iter);
1399
1400         if (muxer_msg_iter) {
1401                 destroy_muxer_msg_iter(muxer_msg_iter);
1402         }
1403 }
1404
1405 BT_HIDDEN
1406 bt_message_iterator_class_next_method_status muxer_msg_iter_next(
1407                 bt_self_message_iterator *self_msg_iter,
1408                 bt_message_array_const msgs, uint64_t capacity,
1409                 uint64_t *count)
1410 {
1411         bt_message_iterator_class_next_method_status status;
1412         struct muxer_msg_iter *muxer_msg_iter =
1413                 bt_self_message_iterator_get_data(self_msg_iter);
1414         bt_self_component *self_comp = NULL;
1415         struct muxer_comp *muxer_comp = NULL;
1416
1417         BT_ASSERT_DBG(muxer_msg_iter);
1418         self_comp = bt_self_message_iterator_borrow_component(
1419                 self_msg_iter);
1420         BT_ASSERT_DBG(self_comp);
1421         muxer_comp = bt_self_component_get_data(self_comp);
1422         BT_ASSERT_DBG(muxer_comp);
1423         BT_COMP_LOGT("Muxer component's message iterator's \"next\" method called: "
1424                 "comp-addr=%p, muxer-comp-addr=%p, muxer-msg-iter-addr=%p, "
1425                 "msg-iter-addr=%p",
1426                 self_comp, muxer_comp, muxer_msg_iter, self_msg_iter);
1427
1428         status = muxer_msg_iter_do_next(muxer_comp, muxer_msg_iter,
1429                 msgs, capacity, count);
1430         if (status < 0) {
1431                 BT_COMP_LOGE_APPEND_CAUSE(self_comp,
1432                         "Cannot get next message: "
1433                         "comp-addr=%p, muxer-comp-addr=%p, muxer-msg-iter-addr=%p, "
1434                         "msg-iter-addr=%p, status=%s",
1435                         self_comp, muxer_comp, muxer_msg_iter, self_msg_iter,
1436                         bt_common_func_status_string(status));
1437         } else {
1438                 BT_COMP_LOGT("Returning from muxer component's message iterator's \"next\" method: "
1439                         "status=%s",
1440                         bt_common_func_status_string(status));
1441         }
1442
1443         return status;
1444 }
1445
1446 BT_HIDDEN
1447 bt_component_class_port_connected_method_status muxer_input_port_connected(
1448                 bt_self_component_filter *self_comp,
1449                 bt_self_component_port_input *self_port,
1450                 const bt_port_output *other_port)
1451 {
1452         bt_component_class_port_connected_method_status status =
1453                 BT_COMPONENT_CLASS_PORT_CONNECTED_METHOD_STATUS_OK;
1454         bt_self_component_add_port_status add_port_status;
1455         struct muxer_comp *muxer_comp = bt_self_component_get_data(
1456                 bt_self_component_filter_as_self_component(self_comp));
1457
1458         add_port_status = add_available_input_port(self_comp);
1459         if (add_port_status) {
1460                 BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
1461                         "Cannot add one muxer component's input port: status=%s",
1462                         bt_common_func_status_string(add_port_status));
1463
1464                 if (add_port_status ==
1465                                 BT_SELF_COMPONENT_ADD_PORT_STATUS_MEMORY_ERROR) {
1466                         status = BT_COMPONENT_CLASS_PORT_CONNECTED_METHOD_STATUS_MEMORY_ERROR;
1467                 } else {
1468                         status = BT_COMPONENT_CLASS_PORT_CONNECTED_METHOD_STATUS_ERROR;
1469                 }
1470
1471                 goto end;
1472         }
1473
1474 end:
1475         return status;
1476 }
1477
1478 static inline
1479 bt_message_iterator_class_can_seek_beginning_method_status
1480 muxer_upstream_msg_iters_can_all_seek_beginning(
1481                 struct muxer_comp *muxer_comp,
1482                 GPtrArray *muxer_upstream_msg_iters, bt_bool *can_seek)
1483 {
1484         bt_message_iterator_class_can_seek_beginning_method_status status =
1485                 BT_MESSAGE_ITERATOR_CLASS_CAN_SEEK_BEGINNING_METHOD_STATUS_OK;
1486         uint64_t i;
1487
1488         for (i = 0; i < muxer_upstream_msg_iters->len; i++) {
1489                 struct muxer_upstream_msg_iter *upstream_msg_iter =
1490                         muxer_upstream_msg_iters->pdata[i];
1491                 status = (int) bt_message_iterator_can_seek_beginning(
1492                         upstream_msg_iter->msg_iter, can_seek);
1493                 if (status != BT_MESSAGE_ITERATOR_CLASS_CAN_SEEK_BEGINNING_METHOD_STATUS_OK) {
1494                         BT_COMP_LOGE_APPEND_CAUSE(muxer_comp->self_comp,
1495                                 "Failed to determine whether upstream message iterator can seek beginning: "
1496                                 "msg-iter-addr=%p", upstream_msg_iter->msg_iter);
1497                         goto end;
1498                 }
1499
1500                 if (!*can_seek) {
1501                         goto end;
1502                 }
1503         }
1504
1505         *can_seek = BT_TRUE;
1506
1507 end:
1508         return status;
1509 }
1510
1511 BT_HIDDEN
1512 bt_message_iterator_class_can_seek_beginning_method_status
1513 muxer_msg_iter_can_seek_beginning(
1514                 bt_self_message_iterator *self_msg_iter, bt_bool *can_seek)
1515 {
1516         struct muxer_msg_iter *muxer_msg_iter =
1517                 bt_self_message_iterator_get_data(self_msg_iter);
1518         bt_message_iterator_class_can_seek_beginning_method_status status;
1519
1520         status = muxer_upstream_msg_iters_can_all_seek_beginning(
1521                 muxer_msg_iter->muxer_comp,
1522                 muxer_msg_iter->active_muxer_upstream_msg_iters, can_seek);
1523         if (status != BT_MESSAGE_ITERATOR_CLASS_CAN_SEEK_BEGINNING_METHOD_STATUS_OK) {
1524                 goto end;
1525         }
1526
1527         if (!*can_seek) {
1528                 goto end;
1529         }
1530
1531         status = muxer_upstream_msg_iters_can_all_seek_beginning(
1532                 muxer_msg_iter->muxer_comp,
1533                 muxer_msg_iter->ended_muxer_upstream_msg_iters, can_seek);
1534
1535 end:
1536         return status;
1537 }
1538
1539 BT_HIDDEN
1540 bt_message_iterator_class_seek_beginning_method_status muxer_msg_iter_seek_beginning(
1541                 bt_self_message_iterator *self_msg_iter)
1542 {
1543         struct muxer_msg_iter *muxer_msg_iter =
1544                 bt_self_message_iterator_get_data(self_msg_iter);
1545         bt_message_iterator_class_seek_beginning_method_status status =
1546                 BT_MESSAGE_ITERATOR_CLASS_SEEK_BEGINNING_METHOD_STATUS_OK;
1547         bt_message_iterator_seek_beginning_status seek_beg_status;
1548         uint64_t i;
1549
1550         /* Seek all ended upstream iterators first */
1551         for (i = 0; i < muxer_msg_iter->ended_muxer_upstream_msg_iters->len;
1552                         i++) {
1553                 struct muxer_upstream_msg_iter *upstream_msg_iter =
1554                         muxer_msg_iter->ended_muxer_upstream_msg_iters->pdata[i];
1555
1556                 seek_beg_status = bt_message_iterator_seek_beginning(
1557                         upstream_msg_iter->msg_iter);
1558                 if (seek_beg_status != BT_MESSAGE_ITERATOR_SEEK_BEGINNING_STATUS_OK) {
1559                         status = (int) seek_beg_status;
1560                         goto end;
1561                 }
1562
1563                 empty_message_queue(upstream_msg_iter);
1564         }
1565
1566         /* Seek all previously active upstream iterators */
1567         for (i = 0; i < muxer_msg_iter->active_muxer_upstream_msg_iters->len;
1568                         i++) {
1569                 struct muxer_upstream_msg_iter *upstream_msg_iter =
1570                         muxer_msg_iter->active_muxer_upstream_msg_iters->pdata[i];
1571
1572                 seek_beg_status = bt_message_iterator_seek_beginning(
1573                         upstream_msg_iter->msg_iter);
1574                 if (seek_beg_status != BT_MESSAGE_ITERATOR_SEEK_BEGINNING_STATUS_OK) {
1575                         status = (int) seek_beg_status;
1576                         goto end;
1577                 }
1578
1579                 empty_message_queue(upstream_msg_iter);
1580         }
1581
1582         /* Make them all active */
1583         for (i = 0; i < muxer_msg_iter->ended_muxer_upstream_msg_iters->len;
1584                         i++) {
1585                 struct muxer_upstream_msg_iter *upstream_msg_iter =
1586                         muxer_msg_iter->ended_muxer_upstream_msg_iters->pdata[i];
1587
1588                 g_ptr_array_add(muxer_msg_iter->active_muxer_upstream_msg_iters,
1589                         upstream_msg_iter);
1590                 muxer_msg_iter->ended_muxer_upstream_msg_iters->pdata[i] = NULL;
1591         }
1592
1593         /*
1594          * GLib < 2.48.0 asserts when g_ptr_array_remove_range() is
1595          * called on an empty array.
1596          */
1597         if (muxer_msg_iter->ended_muxer_upstream_msg_iters->len > 0) {
1598                 g_ptr_array_remove_range(muxer_msg_iter->ended_muxer_upstream_msg_iters,
1599                         0, muxer_msg_iter->ended_muxer_upstream_msg_iters->len);
1600         }
1601         muxer_msg_iter->last_returned_ts_ns = INT64_MIN;
1602         muxer_msg_iter->clock_class_expectation =
1603                 MUXER_MSG_ITER_CLOCK_CLASS_EXPECTATION_ANY;
1604
1605 end:
1606         return status;
1607 }