lib/graph/graph.c

   1 /*
   2  * graph.c
   3  *
   4  * Babeltrace Plugin Component Graph
   5  *
   6  * Copyright 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   7  * Copyright 2017 Philippe Proulx <pproulx@efficios.com>
   8  *
   9  * Permission is hereby granted, free of charge, to any person obtaining a copy
  10  * of this software and associated documentation files (the "Software"), to deal
  11  * in the Software without restriction, including without limitation the rights
  12  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  13  * copies of the Software, and to permit persons to whom the Software is
  14  * furnished to do so, subject to the following conditions:
  15  *
  16  * The above copyright notice and this permission notice shall be included in
  17  * all copies or substantial portions of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  22  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  23  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  24  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  25  * SOFTWARE.
  26  */
  27
  28 #define BT_LOG_TAG "GRAPH"
  29 #include <babeltrace/lib-logging-internal.h>
  30
  31 #include <babeltrace/graph/component-internal.h>
  32 #include <babeltrace/graph/graph-internal.h>
  33 #include <babeltrace/graph/connection-internal.h>
  34 #include <babeltrace/graph/component-sink-internal.h>
  35 #include <babeltrace/graph/component-source.h>
  36 #include <babeltrace/graph/component-filter.h>
  37 #include <babeltrace/graph/port.h>
  38 #include <babeltrace/compiler-internal.h>
  39 #include <babeltrace/types.h>
  40 #include <unistd.h>
  41 #include <glib.h>
  42
  43 struct bt_graph_listener {
  44         void *func;
  45         void *data;
  46 };
  47
  48 static
  49 void bt_graph_destroy(struct bt_object *obj)
  50 {
  51         struct bt_graph *graph = container_of(obj,
  52                         struct bt_graph, base);
  53
  54         /*
  55          * The graph's reference count is 0 if we're here. Increment
  56          * it to avoid a double-destroy (possibly infinitely recursive)
  57          * in this situation:
  58          *
  59          * 1. We put and destroy a connection.
  60          * 2. This connection's destructor finalizes its active
  61          *    notification iterators.
  62          * 3. A notification iterator's finalization function gets a
  63          *    new reference on its component (reference count goes from
  64          *    0 to 1).
  65          * 4. Since this component's reference count goes to 1, it takes
  66          *    a reference on its parent (this graph). This graph's
  67          *    reference count goes from 0 to 1.
  68          * 5. The notification iterator's finalization function puts its
  69          *    component reference (reference count goes from 1 to 0).
  70          * 6. Since this component's reference count goes from 1 to 0,
  71          *    it puts its parent (this graph). This graph's reference
  72          *    count goes from 1 to 0.
  73          * 7. Since this graph's reference count goes from 1 to 0,
  74          *    its destructor is called (this function).
  75          *
  76          * With the incrementation below, the graph's reference count at
  77          * step 4 goes from 1 to 2, and from 2 to 1 at step 6. This
  78          * ensures that this function is not called two times.
  79          */
  80         BT_LOGD("Destroying graph: addr=%p", graph);
  81         obj->ref_count.count++;
  82
  83         if (graph->connections) {
  84                 BT_LOGD_STR("Destroying connections.");
  85                 g_ptr_array_free(graph->connections, TRUE);
  86         }
  87         if (graph->components) {
  88                 BT_LOGD_STR("Destroying components.");
  89                 g_ptr_array_free(graph->components, TRUE);
  90         }
  91         if (graph->sinks_to_consume) {
  92                 g_queue_free(graph->sinks_to_consume);
  93         }
  94
  95         if (graph->listeners.port_added) {
  96                 g_array_free(graph->listeners.port_added, TRUE);
  97         }
  98
  99         if (graph->listeners.port_removed) {
 100                 g_array_free(graph->listeners.port_removed, TRUE);
 101         }
 102
 103         if (graph->listeners.ports_connected) {
 104                 g_array_free(graph->listeners.ports_connected, TRUE);
 105         }
 106
 107         if (graph->listeners.ports_disconnected) {
 108                 g_array_free(graph->listeners.ports_disconnected, TRUE);
 109         }
 110
 111         g_free(graph);
 112 }
 113
 114 static
 115 int init_listeners_array(GArray **listeners)
 116 {
 117         int ret = 0;
 118
 119         assert(listeners);
 120         *listeners = g_array_new(FALSE, TRUE, sizeof(struct bt_graph_listener));
 121         if (!*listeners) {
 122                 BT_LOGE_STR("Failed to allocate one GArray.");
 123                 ret = -1;
 124                 goto end;
 125         }
 126
 127 end:
 128         return ret;
 129 }
 130
 131 struct bt_graph *bt_graph_create(void)
 132 {
 133         struct bt_graph *graph;
 134         int ret;
 135
 136         BT_LOGD_STR("Creating graph object.");
 137         graph = g_new0(struct bt_graph, 1);
 138         if (!graph) {
 139                 BT_LOGE_STR("Failed to allocate one graph.");
 140                 goto end;
 141         }
 142
 143         bt_object_init(graph, bt_graph_destroy);
 144
 145         graph->connections = g_ptr_array_new_with_free_func(bt_object_release);
 146         if (!graph->connections) {
 147                 BT_LOGE_STR("Failed to allocate one GPtrArray.");
 148                 goto error;
 149         }
 150         graph->components = g_ptr_array_new_with_free_func(bt_object_release);
 151         if (!graph->components) {
 152                 BT_LOGE_STR("Failed to allocate one GPtrArray.");
 153                 goto error;
 154         }
 155         graph->sinks_to_consume = g_queue_new();
 156         if (!graph->sinks_to_consume) {
 157                 BT_LOGE_STR("Failed to allocate one GQueue.");
 158                 goto error;
 159         }
 160
 161         ret = init_listeners_array(&graph->listeners.port_added);
 162         if (ret) {
 163                 BT_LOGE_STR("Cannot create the \"port added\" listener array.");
 164                 goto error;
 165         }
 166
 167         ret = init_listeners_array(&graph->listeners.port_removed);
 168         if (ret) {
 169                 BT_LOGE_STR("Cannot create the \"port removed\" listener array.");
 170                 goto error;
 171         }
 172
 173         ret = init_listeners_array(&graph->listeners.ports_connected);
 174         if (ret) {
 175                 BT_LOGE_STR("Cannot create the \"port connected\" listener array.");
 176                 goto error;
 177         }
 178
 179         ret = init_listeners_array(&graph->listeners.ports_disconnected);
 180         if (ret) {
 181                 BT_LOGE_STR("Cannot create the \"port disconneted\" listener array.");
 182                 goto error;
 183         }
 184
 185         BT_LOGD("Created graph object: addr=%p", graph);
 186
 187 end:
 188         return graph;
 189 error:
 190         BT_PUT(graph);
 191         goto end;
 192 }
 193
 194 enum bt_graph_status bt_graph_connect_ports(struct bt_graph *graph,
 195                 struct bt_port *upstream_port, struct bt_port *downstream_port,
 196                 struct bt_connection **user_connection)
 197 {
 198         enum bt_graph_status status = BT_GRAPH_STATUS_OK;
 199         struct bt_connection *connection = NULL;
 200         struct bt_graph *upstream_graph = NULL;
 201         struct bt_graph *downstream_graph = NULL;
 202         struct bt_component *upstream_component = NULL;
 203         struct bt_component *downstream_component = NULL;
 204         enum bt_component_status component_status;
 205         bt_bool upstream_was_already_in_graph;
 206         bt_bool downstream_was_already_in_graph;
 207
 208         if (!graph) {
 209                 BT_LOGW_STR("Invalid parameter: graph is NULL.");
 210                 status = BT_GRAPH_STATUS_INVALID;
 211                 goto end;
 212         }
 213
 214         if (!upstream_port) {
 215                 BT_LOGW_STR("Invalid parameter: upstream port is NULL.");
 216                 status = BT_GRAPH_STATUS_INVALID;
 217                 goto end;
 218         }
 219
 220         if (!downstream_port) {
 221                 BT_LOGW_STR("Invalid parameter: downstream port is NULL.");
 222                 status = BT_GRAPH_STATUS_INVALID;
 223                 goto end;
 224         }
 225
 226         BT_LOGD("Connecting component ports within graph: "
 227                 "graph-addr=%p, "
 228                 "upstream-port-addr=%p, upstream-port-name=\"%s\", "
 229                 "downstream-port-addr=%p, downstream-port-name=\"%s\"",
 230                 graph, upstream_port, bt_port_get_name(upstream_port),
 231                 downstream_port, bt_port_get_name(downstream_port));
 232
 233         if (graph->canceled) {
 234                 BT_LOGW_STR("Invalid parameter: graph is canceled.");
 235                 status = BT_GRAPH_STATUS_CANCELED;
 236                 goto end;
 237         }
 238
 239         /* Ensure appropriate types for upstream and downstream ports. */
 240         if (bt_port_get_type(upstream_port) != BT_PORT_TYPE_OUTPUT) {
 241                 BT_LOGW_STR("Invalid parameter: upstream port is not an output port.");
 242                 status = BT_GRAPH_STATUS_INVALID;
 243                 goto end;
 244         }
 245         if (bt_port_get_type(downstream_port) != BT_PORT_TYPE_INPUT) {
 246                 BT_LOGW_STR("Invalid parameter: downstream port is not an input port.");
 247                 status = BT_GRAPH_STATUS_INVALID;
 248                 goto end;
 249         }
 250
 251         /* Ensure that both ports are currently unconnected. */
 252         if (bt_port_is_connected(upstream_port)) {
 253                 BT_LOGW_STR("Invalid parameter: upstream port is already connected.");
 254                 status = BT_GRAPH_STATUS_INVALID;
 255                 goto end;
 256         }
 257
 258         if (bt_port_is_connected(downstream_port)) {
 259                 BT_LOGW_STR("Invalid parameter: downstream port is already connected.");
 260                 status = BT_GRAPH_STATUS_INVALID;
 261                 goto end;
 262         }
 263
 264         /*
 265          * Ensure that both ports are still attached to their creating
 266          * component.
 267          */
 268         upstream_component = bt_port_get_component(upstream_port);
 269         if (!upstream_component) {
 270                 BT_LOGW_STR("Invalid parameter: upstream port is loose (does not belong to a component)");
 271                 status = BT_GRAPH_STATUS_INVALID;
 272                 goto end;
 273         }
 274
 275         downstream_component = bt_port_get_component(downstream_port);
 276         if (!downstream_component) {
 277                 BT_LOGW_STR("Invalid parameter: downstream port is loose (does not belong to a component)");
 278                 status = BT_GRAPH_STATUS_INVALID;
 279                 goto end;
 280         }
 281
 282         BT_LOGD("Connecting component ports: "
 283                 "upstream-comp-addr=%p, upstream-comp-name=\"%s\", "
 284                 "downstream-comp-addr=%p, downstream-comp-name=\"%s\"",
 285                 upstream_component, bt_component_get_name(upstream_component),
 286                 downstream_component, bt_component_get_name(downstream_component));
 287
 288         /* Ensure the components are not already part of another graph. */
 289         upstream_graph = bt_component_get_graph(upstream_component);
 290         if (upstream_graph && (graph != upstream_graph)) {
 291                 BT_LOGW("Invalid parameter: upstream port's component is already part of another graph: "
 292                         "other-graph-addr=%p", upstream_graph);
 293                 status = BT_GRAPH_STATUS_ALREADY_IN_A_GRAPH;
 294                 goto end;
 295         }
 296         upstream_was_already_in_graph = (graph == upstream_graph);
 297         downstream_graph = bt_component_get_graph(downstream_component);
 298         if (downstream_graph && (graph != downstream_graph)) {
 299                 BT_LOGW("Invalid parameter: downstream port's component is already part of another graph: "
 300                         "other-graph-addr=%p", downstream_graph);
 301                 status = BT_GRAPH_STATUS_ALREADY_IN_A_GRAPH;
 302                 goto end;
 303         }
 304         downstream_was_already_in_graph = (graph == downstream_graph);
 305
 306         /*
 307          * At this point the ports are not connected yet. Both
 308          * components need to accept an eventual connection to their
 309          * port by the other port before we continue.
 310          */
 311         BT_LOGD_STR("Asking upstream component to accept the connection.");
 312         component_status = bt_component_accept_port_connection(
 313                 upstream_component, upstream_port, downstream_port);
 314         if (component_status != BT_COMPONENT_STATUS_OK) {
 315                 if (component_status == BT_COMPONENT_STATUS_REFUSE_PORT_CONNECTION) {
 316                         BT_LOGD_STR("Upstream component refused the connection.");
 317                 } else {
 318                         BT_LOGW("Cannot ask upstream component to accept the connection: "
 319                                 "status=%s", bt_component_status_string(component_status));
 320                 }
 321
 322                 status = bt_graph_status_from_component_status(
 323                         component_status);
 324                 goto end;
 325         }
 326
 327         BT_LOGD_STR("Asking downstream component to accept the connection.");
 328         component_status = bt_component_accept_port_connection(
 329                 downstream_component, downstream_port, upstream_port);
 330         if (component_status != BT_COMPONENT_STATUS_OK) {
 331                 if (component_status == BT_COMPONENT_STATUS_REFUSE_PORT_CONNECTION) {
 332                         BT_LOGD_STR("Downstream component refused the connection.");
 333                 } else {
 334                         BT_LOGW("Cannot ask downstream component to accept the connection: "
 335                                 "status=%s", bt_component_status_string(component_status));
 336                 }
 337
 338                 status = bt_graph_status_from_component_status(
 339                         component_status);
 340                 goto end;
 341         }
 342
 343         BT_LOGD_STR("Creating connection.");
 344         connection = bt_connection_create(graph, upstream_port,
 345                         downstream_port);
 346         if (!connection) {
 347                 BT_LOGW("Cannot create connection object.");
 348                 status = BT_GRAPH_STATUS_NOMEM;
 349                 goto end;
 350         }
 351
 352         BT_LOGD("Connection object created: conn-addr=%p", connection);
 353
 354         /*
 355          * Ownership of upstream_component/downstream_component and of
 356          * the connection object is transferred to the graph.
 357          */
 358         g_ptr_array_add(graph->connections, connection);
 359
 360         if (!upstream_was_already_in_graph) {
 361                 g_ptr_array_add(graph->components, upstream_component);
 362                 bt_component_set_graph(upstream_component, graph);
 363         }
 364         if (!downstream_was_already_in_graph) {
 365                 g_ptr_array_add(graph->components, downstream_component);
 366                 bt_component_set_graph(downstream_component, graph);
 367                 if (bt_component_get_class_type(downstream_component) ==
 368                                 BT_COMPONENT_CLASS_TYPE_SINK) {
 369                         g_queue_push_tail(graph->sinks_to_consume,
 370                                         downstream_component);
 371                 }
 372         }
 373
 374         /*
 375          * The graph is now the parent of these components which
 376          * garantees their existence for the duration of the graph's
 377          * lifetime.
 378          */
 379
 380         /*
 381          * Notify both components that their port is connected.
 382          */
 383         BT_LOGD_STR("Notifying upstream component that its port is connected.");
 384         bt_component_port_connected(upstream_component, upstream_port,
 385                 downstream_port);
 386         BT_LOGD_STR("Notifying downstream component that its port is connected.");
 387         bt_component_port_connected(downstream_component, downstream_port,
 388                 upstream_port);
 389
 390         /*
 391          * Notify the graph's creator that both ports are connected.
 392          */
 393         BT_LOGD_STR("Notifying graph's user that new component ports are connected.");
 394         bt_graph_notify_ports_connected(graph, upstream_port, downstream_port);
 395         BT_LOGD("Connected component ports within graph: "
 396                 "graph-addr=%p, "
 397                 "upstream-comp-addr=%p, upstream-comp-name=\"%s\", "
 398                 "downstream-comp-addr=%p, downstream-comp-name=\"%s\", "
 399                 "upstream-port-addr=%p, upstream-port-name=\"%s\", "
 400                 "downstream-port-addr=%p, downstream-port-name=\"%s\"",
 401                 graph,
 402                 upstream_component, bt_component_get_name(upstream_component),
 403                 downstream_component, bt_component_get_name(downstream_component),
 404                 upstream_port, bt_port_get_name(upstream_port),
 405                 downstream_port, bt_port_get_name(downstream_port));
 406
 407         if (user_connection) {
 408                 BT_MOVE(*user_connection, connection);
 409         }
 410
 411 end:
 412         bt_put(upstream_graph);
 413         bt_put(downstream_graph);
 414         bt_put(upstream_component);
 415         bt_put(downstream_component);
 416         bt_put(connection);
 417         return status;
 418 }
 419
 420 static
 421 enum bt_graph_status bt_graph_consume_no_check(struct bt_graph *graph)
 422 {
 423         struct bt_component *sink;
 424         enum bt_graph_status status = BT_GRAPH_STATUS_OK;
 425         enum bt_component_status comp_status;
 426         GList *current_node;
 427
 428         BT_LOGV("Making next sink consume: addr=%p", graph);
 429
 430         if (g_queue_is_empty(graph->sinks_to_consume)) {
 431                 BT_LOGV_STR("Graph's sink queue is empty: end of graph.");
 432                 status = BT_GRAPH_STATUS_END;
 433                 goto end;
 434         }
 435
 436         current_node = g_queue_pop_head_link(graph->sinks_to_consume);
 437         sink = current_node->data;
 438         BT_LOGV("Chose next sink to consume: comp-addr=%p, comp-name=\"%s\"",
 439                 sink, bt_component_get_name(sink));
 440         comp_status = bt_component_sink_consume(sink);
 441         BT_LOGV("Consumed from sink: status=%s",
 442                 bt_component_status_string(comp_status));
 443         switch (comp_status) {
 444         case BT_COMPONENT_STATUS_OK:
 445                 break;
 446         case BT_COMPONENT_STATUS_END:
 447                 status = BT_GRAPH_STATUS_END;
 448                 break;
 449         case BT_COMPONENT_STATUS_AGAIN:
 450                 status = BT_GRAPH_STATUS_AGAIN;
 451                 break;
 452         case BT_COMPONENT_STATUS_INVALID:
 453                 status = BT_GRAPH_STATUS_INVALID;
 454                 break;
 455         default:
 456                 status = BT_GRAPH_STATUS_ERROR;
 457                 break;
 458         }
 459
 460         if (status != BT_GRAPH_STATUS_END) {
 461                 g_queue_push_tail_link(graph->sinks_to_consume, current_node);
 462                 goto end;
 463         }
 464
 465         /* End reached, the node is not added back to the queue and free'd. */
 466         g_queue_delete_link(graph->sinks_to_consume, current_node);
 467
 468         /* Don't forward an END status if there are sinks left to consume. */
 469         if (!g_queue_is_empty(graph->sinks_to_consume)) {
 470                 status = BT_GRAPH_STATUS_OK;
 471                 goto end;
 472         }
 473 end:
 474         BT_LOGV("Graph consumed: status=%s", bt_graph_status_string(status));
 475         return status;
 476 }
 477
 478 enum bt_graph_status bt_graph_consume(struct bt_graph *graph)
 479 {
 480         enum bt_graph_status status = BT_GRAPH_STATUS_OK;
 481
 482         if (!graph) {
 483                 BT_LOGW_STR("Invalid parameter: graph is NULL.");
 484                 status = BT_GRAPH_STATUS_INVALID;
 485                 goto end;
 486         }
 487
 488         if (graph->canceled) {
 489                 BT_LOGW("Invalid parameter: graph is canceled: "
 490                         "graph-addr=%p", graph);
 491                 status = BT_GRAPH_STATUS_CANCELED;
 492                 goto end;
 493         }
 494
 495         status = bt_graph_consume_no_check(graph);
 496
 497 end:
 498         return status;
 499 }
 500
 501 enum bt_graph_status bt_graph_run(struct bt_graph *graph)
 502 {
 503         enum bt_graph_status status = BT_GRAPH_STATUS_OK;
 504
 505         if (!graph) {
 506                 BT_LOGW_STR("Invalid parameter: graph is NULL.");
 507                 status = BT_GRAPH_STATUS_INVALID;
 508                 goto end;
 509         }
 510
 511         if (graph->canceled) {
 512                 BT_LOGW("Invalid parameter: graph is canceled: "
 513                         "graph-addr=%p", graph);
 514                 status = BT_GRAPH_STATUS_CANCELED;
 515                 goto end;
 516         }
 517
 518         BT_LOGV("Running graph: addr=%p", graph);
 519
 520         do {
 521                 /*
 522                  * Check if the graph is canceled at each iteration. If
 523                  * the graph was canceled by another thread or by a
 524                  * signal, this is not a warning nor an error, it was
 525                  * intentional: log with a DEBUG level only.
 526                  */
 527                 if (graph->canceled) {
 528                         BT_LOGD("Stopping the graph: graph is canceled: "
 529                                 "graph-addr=%p", graph);
 530                         status = BT_GRAPH_STATUS_CANCELED;
 531                         goto end;
 532                 }
 533
 534                 status = bt_graph_consume(graph);
 535                 if (status == BT_GRAPH_STATUS_AGAIN) {
 536                         /*
 537                          * If AGAIN is received and there are multiple
 538                          * sinks, go ahead and consume from the next
 539                          * sink.
 540                          *
 541                          * However, in the case where a single sink is
 542                          * left, the caller can decide to busy-wait and
 543                          * call bt_graph_run() continuously until the
 544                          * source is ready or it can decide to sleep for
 545                          * an arbitrary amount of time.
 546                          */
 547                         if (graph->sinks_to_consume->length > 1) {
 548                                 status = BT_GRAPH_STATUS_OK;
 549                         }
 550                 }
 551         } while (status == BT_GRAPH_STATUS_OK);
 552
 553         if (g_queue_is_empty(graph->sinks_to_consume)) {
 554                 status = BT_GRAPH_STATUS_END;
 555         }
 556
 557 end:
 558         BT_LOGV("Graph ran: status=%s", bt_graph_status_string(status));
 559         return status;
 560 }
 561
 562 static
 563 int add_listener(GArray *listeners, void *func, void *data)
 564 {
 565         struct bt_graph_listener listener = {
 566                 .func = func,
 567                 .data = data,
 568         };
 569
 570         g_array_append_val(listeners, listener);
 571         return listeners->len - 1;
 572 }
 573
 574 int bt_graph_add_port_added_listener(
 575                 struct bt_graph *graph,
 576                 bt_graph_port_added_listener listener, void *data)
 577 {
 578         int ret;
 579
 580         if (!graph) {
 581                 BT_LOGW_STR("Invalid parameter: graph is NULL.");
 582                 ret = -1;
 583                 goto end;
 584         }
 585
 586         if (!listener) {
 587                 BT_LOGW_STR("Invalid parameter: listener is NULL.");
 588                 ret = -1;
 589                 goto end;
 590         }
 591
 592         ret = add_listener(graph->listeners.port_added, listener, data);
 593         BT_LOGV("Added \"port added\" listener to graph: "
 594                 "graph-addr=%p, listener-addr=%p, pos=%d",
 595                 graph, listener, ret);
 596
 597 end:
 598         return ret;
 599 }
 600
 601 int bt_graph_add_port_removed_listener(
 602                 struct bt_graph *graph,
 603                 bt_graph_port_removed_listener listener, void *data)
 604 {
 605         int ret;
 606
 607         if (!graph) {
 608                 BT_LOGW_STR("Invalid parameter: graph is NULL.");
 609                 ret = -1;
 610                 goto end;
 611         }
 612
 613         if (!listener) {
 614                 BT_LOGW_STR("Invalid parameter: listener is NULL.");
 615                 ret = -1;
 616                 goto end;
 617         }
 618
 619         ret = add_listener(graph->listeners.port_removed, listener, data);
 620         BT_LOGV("Added \"port removed\" listener to graph: "
 621                 "graph-addr=%p, listener-addr=%p, pos=%d",
 622                 graph, listener, ret);
 623
 624 end:
 625         return ret;
 626 }
 627
 628 int bt_graph_add_ports_connected_listener(
 629                 struct bt_graph *graph,
 630                 bt_graph_ports_connected_listener listener, void *data)
 631 {
 632         int ret;
 633
 634         if (!graph) {
 635                 BT_LOGW_STR("Invalid parameter: graph is NULL.");
 636                 ret = -1;
 637                 goto end;
 638         }
 639
 640         if (!listener) {
 641                 BT_LOGW_STR("Invalid parameter: listener is NULL.");
 642                 ret = -1;
 643                 goto end;
 644         }
 645
 646         ret = add_listener(graph->listeners.ports_connected, listener, data);
 647         BT_LOGV("Added \"port connected\" listener to graph: "
 648                 "graph-addr=%p, listener-addr=%p, pos=%d",
 649                 graph, listener, ret);
 650
 651 end:
 652         return ret;
 653 }
 654
 655 int bt_graph_add_ports_disconnected_listener(
 656                 struct bt_graph *graph,
 657                 bt_graph_ports_disconnected_listener listener, void *data)
 658 {
 659         int ret;
 660
 661         if (!graph) {
 662                 BT_LOGW_STR("Invalid parameter: graph is NULL.");
 663                 ret = -1;
 664                 goto end;
 665         }
 666
 667         if (!listener) {
 668                 BT_LOGW_STR("Invalid parameter: listener is NULL.");
 669                 ret = -1;
 670                 goto end;
 671         }
 672
 673         ret = add_listener(graph->listeners.ports_disconnected, listener, data);
 674         BT_LOGV("Added \"port disconnected\" listener to graph: "
 675                 "graph-addr=%p, listener-addr=%p, pos=%d",
 676                 graph, listener, ret);
 677
 678 end:
 679         return ret;
 680 }
 681
 682 BT_HIDDEN
 683 void bt_graph_notify_port_added(struct bt_graph *graph, struct bt_port *port)
 684 {
 685         size_t i;
 686
 687         BT_LOGV("Notifying graph listeners that a port was added: "
 688                 "graph-addr=%p, port-addr=%p, port-name=\"%s\"",
 689                 graph, port, bt_port_get_name(port));
 690
 691         for (i = 0; i < graph->listeners.port_added->len; i++) {
 692                 struct bt_graph_listener listener =
 693                         g_array_index(graph->listeners.port_added,
 694                                 struct bt_graph_listener, i);
 695                 bt_graph_port_added_listener func = listener.func;
 696
 697                 assert(func);
 698                 func(port, listener.data);
 699         }
 700 }
 701
 702 BT_HIDDEN
 703 void bt_graph_notify_port_removed(struct bt_graph *graph,
 704                 struct bt_component *comp, struct bt_port *port)
 705 {
 706         size_t i;
 707
 708         BT_LOGV("Notifying graph listeners that a port was removed: "
 709                 "graph-addr=%p, port-addr=%p, port-name=\"%s\"",
 710                 graph, port, bt_port_get_name(port));
 711
 712         for (i = 0; i < graph->listeners.port_removed->len; i++) {
 713                 struct bt_graph_listener listener =
 714                         g_array_index(graph->listeners.port_removed,
 715                                 struct bt_graph_listener, i);
 716                 bt_graph_port_removed_listener func = listener.func;
 717
 718                 assert(func);
 719                 func(comp, port, listener.data);
 720         }
 721 }
 722
 723 BT_HIDDEN
 724 void bt_graph_notify_ports_connected(struct bt_graph *graph,
 725                 struct bt_port *upstream_port, struct bt_port *downstream_port)
 726 {
 727         size_t i;
 728
 729         BT_LOGV("Notifying graph listeners that two ports were connected: "
 730                 "graph-addr=%p, "
 731                 "upstream-port-addr=%p, upstream-port-name=\"%s\", "
 732                 "downstream-port-addr=%p, downstream-port-name=\"%s\"",
 733                 graph, upstream_port, bt_port_get_name(upstream_port),
 734                 downstream_port, bt_port_get_name(downstream_port));
 735
 736         for (i = 0; i < graph->listeners.ports_connected->len; i++) {
 737                 struct bt_graph_listener listener =
 738                         g_array_index(graph->listeners.ports_connected,
 739                                 struct bt_graph_listener, i);
 740                 bt_graph_ports_connected_listener func = listener.func;
 741
 742                 assert(func);
 743                 func(upstream_port, downstream_port, listener.data);
 744         }
 745 }
 746
 747 BT_HIDDEN
 748 void bt_graph_notify_ports_disconnected(struct bt_graph *graph,
 749                 struct bt_component *upstream_comp,
 750                 struct bt_component *downstream_comp,
 751                 struct bt_port *upstream_port, struct bt_port *downstream_port)
 752 {
 753         size_t i;
 754
 755         BT_LOGV("Notifying graph listeners that two ports were disconnected: "
 756                 "graph-addr=%p, "
 757                 "upstream-port-addr=%p, upstream-port-name=\"%s\", "
 758                 "downstream-port-addr=%p, downstream-port-name=\"%s\"",
 759                 graph, upstream_port, bt_port_get_name(upstream_port),
 760                 downstream_port, bt_port_get_name(downstream_port));
 761
 762         for (i = 0; i < graph->listeners.ports_disconnected->len; i++) {
 763                 struct bt_graph_listener listener =
 764                         g_array_index(graph->listeners.ports_disconnected,
 765                                 struct bt_graph_listener, i);
 766                 bt_graph_ports_disconnected_listener func = listener.func;
 767
 768                 assert(func);
 769                 func(upstream_comp, downstream_comp, upstream_port,
 770                         downstream_port, listener.data);
 771         }
 772 }
 773
 774 extern enum bt_graph_status bt_graph_cancel(struct bt_graph *graph)
 775 {
 776         enum bt_graph_status ret = BT_GRAPH_STATUS_OK;
 777
 778         if (!graph) {
 779                 BT_LOGW_STR("Invalid parameter: graph is NULL.");
 780                 ret = BT_GRAPH_STATUS_INVALID;
 781                 goto end;
 782         }
 783
 784         graph->canceled = BT_TRUE;
 785         BT_LOGV("Canceled graph: addr=%p", graph);
 786
 787 end:
 788         return ret;
 789 }
 790
 791 extern bt_bool bt_graph_is_canceled(struct bt_graph *graph)
 792 {
 793         return graph ? graph->canceled : BT_FALSE;
 794 }
 795
 796 BT_HIDDEN
 797 void bt_graph_remove_connection(struct bt_graph *graph,
 798                 struct bt_connection *connection)
 799 {
 800         assert(graph);
 801         assert(connection);
 802         BT_LOGV("Removing graph's connection: graph-addr=%p, conn-addr=%p",
 803                 graph, connection);
 804         g_ptr_array_remove(graph->connections, connection);
 805 }