4 * Babeltrace Plugin Component Graph
6 * Copyright 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
8 * Author: Jérémie Galarneau <jeremie.galarneau@efficios.com>
10 * Permission is hereby granted, free of charge, to any person obtaining a copy
11 * of this software and associated documentation files (the "Software"), to deal
12 * in the Software without restriction, including without limitation the rights
13 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
14 * copies of the Software, and to permit persons to whom the Software is
15 * furnished to do so, subject to the following conditions:
17 * The above copyright notice and this permission notice shall be included in
18 * all copies or substantial portions of the Software.
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
23 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
24 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
25 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
29 #include <babeltrace/graph/component-internal.h>
30 #include <babeltrace/graph/graph-internal.h>
31 #include <babeltrace/graph/connection-internal.h>
32 #include <babeltrace/graph/component-sink-internal.h>
33 #include <babeltrace/graph/component-source.h>
34 #include <babeltrace/graph/component-filter.h>
35 #include <babeltrace/graph/port.h>
36 #include <babeltrace/compiler-internal.h>
40 struct bt_graph_listener
{
46 void bt_graph_destroy(struct bt_object
*obj
)
48 struct bt_graph
*graph
= container_of(obj
,
49 struct bt_graph
, base
);
51 if (graph
->components
) {
52 g_ptr_array_free(graph
->components
, TRUE
);
54 if (graph
->connections
) {
55 g_ptr_array_free(graph
->connections
, TRUE
);
57 if (graph
->sinks_to_consume
) {
58 g_queue_free(graph
->sinks_to_consume
);
61 if (graph
->listeners
.port_added
) {
62 g_array_free(graph
->listeners
.port_added
, TRUE
);
65 if (graph
->listeners
.port_removed
) {
66 g_array_free(graph
->listeners
.port_removed
, TRUE
);
69 if (graph
->listeners
.ports_connected
) {
70 g_array_free(graph
->listeners
.ports_connected
, TRUE
);
73 if (graph
->listeners
.ports_disconnected
) {
74 g_array_free(graph
->listeners
.ports_disconnected
, TRUE
);
81 int init_listeners_array(GArray
**listeners
)
86 *listeners
= g_array_new(FALSE
, TRUE
, sizeof(struct bt_graph_listener
));
96 struct bt_graph
*bt_graph_create(void)
98 struct bt_graph
*graph
;
101 graph
= g_new0(struct bt_graph
, 1);
106 bt_object_init(graph
, bt_graph_destroy
);
108 graph
->connections
= g_ptr_array_new_with_free_func(bt_object_release
);
109 if (!graph
->connections
) {
112 graph
->components
= g_ptr_array_new_with_free_func(bt_object_release
);
113 if (!graph
->components
) {
116 graph
->sinks_to_consume
= g_queue_new();
117 if (!graph
->sinks_to_consume
) {
121 ret
= init_listeners_array(&graph
->listeners
.port_added
);
126 ret
= init_listeners_array(&graph
->listeners
.port_removed
);
131 ret
= init_listeners_array(&graph
->listeners
.ports_connected
);
136 ret
= init_listeners_array(&graph
->listeners
.ports_disconnected
);
148 struct bt_connection
*bt_graph_connect_ports(struct bt_graph
*graph
,
149 struct bt_port
*upstream_port
,
150 struct bt_port
*downstream_port
)
152 struct bt_connection
*connection
= NULL
;
153 struct bt_graph
*upstream_graph
= NULL
;
154 struct bt_graph
*downstream_graph
= NULL
;
155 struct bt_component
*upstream_component
= NULL
;
156 struct bt_component
*downstream_component
= NULL
;
157 struct bt_connection
*existing_conn
= NULL
;
158 enum bt_component_status component_status
;
159 bool upstream_was_already_in_graph
;
160 bool downstream_was_already_in_graph
;
161 int components_to_remove
= 0;
164 if (!graph
|| !upstream_port
|| !downstream_port
) {
168 /* Ensure appropriate types for upstream and downstream ports. */
169 if (bt_port_get_type(upstream_port
) != BT_PORT_TYPE_OUTPUT
) {
172 if (bt_port_get_type(downstream_port
) != BT_PORT_TYPE_INPUT
) {
176 /* Ensure that both ports are currently unconnected. */
177 existing_conn
= bt_port_get_connection(upstream_port
);
178 bt_put(existing_conn
);
180 fprintf(stderr
, "Upstream port is already connected\n");
184 existing_conn
= bt_port_get_connection(downstream_port
);
185 bt_put(existing_conn
);
187 fprintf(stderr
, "Downstream port is already connected\n");
192 * Ensure that both ports are still attached to their creating
195 upstream_component
= bt_port_get_component(upstream_port
);
196 if (!upstream_component
) {
197 fprintf(stderr
, "Upstream port does not belong to a component\n");
201 downstream_component
= bt_port_get_component(downstream_port
);
202 if (!downstream_component
) {
203 fprintf(stderr
, "Downstream port does not belong to a component\n");
207 /* Ensure the components are not already part of another graph. */
208 upstream_graph
= bt_component_get_graph(upstream_component
);
209 if (upstream_graph
&& (graph
!= upstream_graph
)) {
210 fprintf(stderr
, "Upstream component is already part of another graph\n");
213 upstream_was_already_in_graph
= (graph
== upstream_graph
);
214 downstream_graph
= bt_component_get_graph(downstream_component
);
215 if (downstream_graph
&& (graph
!= downstream_graph
)) {
216 fprintf(stderr
, "Downstream component is already part of another graph\n");
219 downstream_was_already_in_graph
= (graph
== downstream_graph
);
221 connection
= bt_connection_create(graph
, upstream_port
,
228 * Ownership of upstream_component/downstream_component and of
229 * the connection object is transferred to the graph.
231 g_ptr_array_add(graph
->connections
, connection
);
233 if (!upstream_was_already_in_graph
) {
234 g_ptr_array_add(graph
->components
, upstream_component
);
235 bt_component_set_graph(upstream_component
, graph
);
237 if (!downstream_was_already_in_graph
) {
238 g_ptr_array_add(graph
->components
, downstream_component
);
239 bt_component_set_graph(downstream_component
, graph
);
240 if (bt_component_get_class_type(downstream_component
) ==
241 BT_COMPONENT_CLASS_TYPE_SINK
) {
242 g_queue_push_tail(graph
->sinks_to_consume
,
243 downstream_component
);
248 * The graph is now the parent of these components which garantees their
249 * existence for the duration of the graph's lifetime.
253 * The components and connection are added to the graph before
254 * invoking the `accept_port_connection` method in order to make
255 * them visible to the components during the method's
258 component_status
= bt_component_accept_port_connection(
259 upstream_component
, upstream_port
, downstream_port
);
260 if (component_status
!= BT_COMPONENT_STATUS_OK
) {
263 component_status
= bt_component_accept_port_connection(
264 downstream_component
, downstream_port
, upstream_port
);
265 if (component_status
!= BT_COMPONENT_STATUS_OK
) {
270 * Both components accepted the connection. Notify the graph's
271 * creator that both ports are connected.
273 bt_graph_notify_ports_connected(graph
, upstream_port
, downstream_port
);
276 bt_put(upstream_graph
);
277 bt_put(downstream_graph
);
278 bt_put(upstream_component
);
279 bt_put(downstream_component
);
283 * Remove newly-added components from the graph, being careful
284 * not to remove a component that was already present in the graph
285 * and is connected to other components.
287 components_to_remove
+= upstream_was_already_in_graph
? 0 : 1;
288 components_to_remove
+= downstream_was_already_in_graph
? 0 : 1;
290 if (!downstream_was_already_in_graph
) {
291 if (bt_component_get_class_type(downstream_component
) ==
292 BT_COMPONENT_CLASS_TYPE_SINK
) {
293 g_queue_pop_tail(graph
->sinks_to_consume
);
296 /* Remove newly created connection. */
297 g_ptr_array_set_size(graph
->connections
,
298 graph
->connections
->len
- 1);
301 * Remove newly added components.
303 * Note that this is a tricky situation. The graph, being the parent
304 * of the components, does not hold a reference to them. Normally,
305 * components are destroyed right away when the graph is released since
306 * the graph, being their parent, bounds their lifetime
307 * (see doc/ref-counting.md).
309 * In this particular case, we must take a number of steps:
310 * 1) unset the components' parent to rollback the initial state of
311 * the components being connected.
312 * Note that the reference taken by the component on its graph is
313 * released by the set_parent call.
314 * 2) set the pointer in the components array to NULL so that the
315 * destruction function called on the array's resize in invoked on
318 * NOTE: Point #1 assumes that *something* holds a reference to both
319 * components being connected. The fact that a reference is being
320 * held to a component means that it must hold a reference to its
321 * parent to prevent the parent from being destroyed (again, refer
322 * to doc/red-counting.md). This reference to a component is
323 * most likely being held *transitively* by the caller which holds
324 * a reference to both ports (a port has its component as a
327 * This assumes that a graph is not connecting components by
328 * itself while not holding a reference to the ports/components
329 * being connected (i.e. "cheating" by using internal APIs).
331 for (i
= 0; i
< components_to_remove
; i
++) {
332 struct bt_component
*component
= g_ptr_array_index(
333 graph
->components
, graph
->components
->len
- 1);
335 bt_component_set_graph(component
, NULL
);
336 g_ptr_array_index(graph
->components
,
337 graph
->components
->len
- 1) = NULL
;
338 g_ptr_array_set_size(graph
->components
,
339 graph
->components
->len
- 1);
341 /* NOTE: Resizing the ptr_arrays invokes the destruction of the elements. */
344 BT_PUT(upstream_component
);
345 BT_PUT(downstream_component
);
350 enum bt_component_status
get_component_port_counts(
351 struct bt_component
*component
, uint64_t *input_count
,
352 uint64_t *output_count
)
354 enum bt_component_status ret
;
356 switch (bt_component_get_class_type(component
)) {
357 case BT_COMPONENT_CLASS_TYPE_SOURCE
:
358 ret
= bt_component_source_get_output_port_count(component
,
360 if (ret
!= BT_COMPONENT_STATUS_OK
) {
364 case BT_COMPONENT_CLASS_TYPE_FILTER
:
365 ret
= bt_component_filter_get_output_port_count(component
,
367 if (ret
!= BT_COMPONENT_STATUS_OK
) {
370 ret
= bt_component_filter_get_input_port_count(component
,
372 if (ret
!= BT_COMPONENT_STATUS_OK
) {
376 case BT_COMPONENT_CLASS_TYPE_SINK
:
377 ret
= bt_component_sink_get_input_port_count(component
,
379 if (ret
!= BT_COMPONENT_STATUS_OK
) {
387 ret
= BT_COMPONENT_STATUS_OK
;
392 enum bt_graph_status
bt_graph_add_component_as_sibling(struct bt_graph
*graph
,
393 struct bt_component
*origin
,
394 struct bt_component
*new_component
)
396 uint64_t origin_input_port_count
= 0;
397 uint64_t origin_output_port_count
= 0;
398 uint64_t new_input_port_count
= 0;
399 uint64_t new_output_port_count
= 0;
400 enum bt_graph_status status
= BT_GRAPH_STATUS_OK
;
401 struct bt_graph
*origin_graph
= NULL
;
402 struct bt_graph
*new_graph
= NULL
;
403 struct bt_port
*origin_port
= NULL
;
404 struct bt_port
*new_port
= NULL
;
405 struct bt_port
*upstream_port
= NULL
;
406 struct bt_port
*downstream_port
= NULL
;
407 struct bt_connection
*origin_connection
= NULL
;
408 struct bt_connection
*new_connection
= NULL
;
411 if (!graph
|| !origin
|| !new_component
) {
412 status
= BT_GRAPH_STATUS_INVALID
;
416 if (bt_component_get_class_type(origin
) !=
417 bt_component_get_class_type(new_component
)) {
418 status
= BT_GRAPH_STATUS_INVALID
;
422 origin_graph
= bt_component_get_graph(origin
);
423 if (!origin_graph
|| (origin_graph
!= graph
)) {
424 status
= BT_GRAPH_STATUS_INVALID
;
428 new_graph
= bt_component_get_graph(new_component
);
430 status
= BT_GRAPH_STATUS_ALREADY_IN_A_GRAPH
;
434 if (get_component_port_counts(origin
, &origin_input_port_count
,
435 &origin_output_port_count
) != BT_COMPONENT_STATUS_OK
) {
436 status
= BT_GRAPH_STATUS_INVALID
;
439 if (get_component_port_counts(new_component
, &new_input_port_count
,
440 &new_output_port_count
) != BT_COMPONENT_STATUS_OK
) {
441 status
= BT_GRAPH_STATUS_INVALID
;
445 if (origin_input_port_count
!= new_input_port_count
||
446 origin_output_port_count
!= new_output_port_count
) {
447 status
= BT_GRAPH_STATUS_INVALID
;
451 /* Replicate input connections. */
452 for (port_index
= 0; port_index
< origin_input_port_count
; port_index
++) {
453 origin_port
= bt_component_get_input_port_at_index(origin
,
456 status
= BT_GRAPH_STATUS_ERROR
;
457 goto error_disconnect
;
460 new_port
= bt_component_get_input_port_at_index(new_component
,
463 status
= BT_GRAPH_STATUS_ERROR
;
464 goto error_disconnect
;
467 origin_connection
= bt_port_get_connection(origin_port
);
468 if (origin_connection
) {
469 upstream_port
= bt_connection_get_upstream_port(
471 if (!upstream_port
) {
472 goto error_disconnect
;
475 new_connection
= bt_graph_connect_ports(graph
,
476 upstream_port
, new_port
);
477 if (!new_connection
) {
478 goto error_disconnect
;
482 BT_PUT(upstream_port
);
483 BT_PUT(origin_connection
);
484 BT_PUT(new_connection
);
489 /* Replicate output connections. */
490 for (port_index
= 0; port_index
< origin_output_port_count
; port_index
++) {
491 origin_port
= bt_component_get_output_port_at_index(origin
,
494 status
= BT_GRAPH_STATUS_ERROR
;
495 goto error_disconnect
;
497 new_port
= bt_component_get_output_port_at_index(new_component
,
500 status
= BT_GRAPH_STATUS_ERROR
;
501 goto error_disconnect
;
504 origin_connection
= bt_port_get_connection(origin_port
);
505 if (origin_connection
) {
506 downstream_port
= bt_connection_get_downstream_port(
508 if (!downstream_port
) {
509 goto error_disconnect
;
512 new_connection
= bt_graph_connect_ports(graph
,
513 new_port
, downstream_port
);
514 if (!new_connection
) {
515 goto error_disconnect
;
519 BT_PUT(downstream_port
);
520 BT_PUT(origin_connection
);
521 BT_PUT(new_connection
);
526 bt_put(origin_graph
);
530 bt_put(upstream_port
);
531 bt_put(downstream_port
);
532 bt_put(origin_connection
);
533 bt_put(new_connection
);
536 /* Destroy all connections of the new component. */
541 enum bt_graph_status
bt_graph_consume(struct bt_graph
*graph
)
543 struct bt_component
*sink
;
544 enum bt_graph_status status
= BT_GRAPH_STATUS_OK
;
545 enum bt_component_status comp_status
;
549 status
= BT_GRAPH_STATUS_INVALID
;
553 if (g_queue_is_empty(graph
->sinks_to_consume
)) {
554 status
= BT_GRAPH_STATUS_END
;
558 current_node
= g_queue_pop_head_link(graph
->sinks_to_consume
);
559 sink
= current_node
->data
;
560 comp_status
= bt_component_sink_consume(sink
);
561 switch (comp_status
) {
562 case BT_COMPONENT_STATUS_OK
:
564 case BT_COMPONENT_STATUS_END
:
565 status
= BT_GRAPH_STATUS_END
;
567 case BT_COMPONENT_STATUS_AGAIN
:
568 status
= BT_GRAPH_STATUS_AGAIN
;
570 case BT_COMPONENT_STATUS_INVALID
:
571 status
= BT_GRAPH_STATUS_INVALID
;
574 status
= BT_GRAPH_STATUS_ERROR
;
578 if (status
!= BT_GRAPH_STATUS_END
) {
579 g_queue_push_tail_link(graph
->sinks_to_consume
, current_node
);
583 /* End reached, the node is not added back to the queue and free'd. */
584 g_queue_delete_link(graph
->sinks_to_consume
, current_node
);
586 /* Don't forward an END status if there are sinks left to consume. */
587 if (!g_queue_is_empty(graph
->sinks_to_consume
)) {
588 status
= BT_GRAPH_STATUS_OK
;
595 enum bt_graph_status
bt_graph_run(struct bt_graph
*graph
)
597 enum bt_graph_status status
= BT_GRAPH_STATUS_OK
;
600 status
= BT_GRAPH_STATUS_INVALID
;
605 status
= bt_graph_consume(graph
);
606 if (status
== BT_GRAPH_STATUS_AGAIN
) {
608 * If AGAIN is received and there are multiple sinks,
609 * go ahead and consume from the next sink.
611 * However, in the case where a single sink is left,
612 * the caller can decide to busy-wait and call
613 * bt_graph_run continuously until the source is ready
614 * or it can decide to sleep for an arbitrary amount of
617 if (graph
->sinks_to_consume
->length
> 1) {
618 status
= BT_GRAPH_STATUS_OK
;
621 } while (status
== BT_GRAPH_STATUS_OK
);
623 if (g_queue_is_empty(graph
->sinks_to_consume
)) {
624 status
= BT_GRAPH_STATUS_END
;
631 void add_listener(GArray
*listeners
, void *func
, void *data
)
633 struct bt_graph_listener listener
= {
638 g_array_append_val(listeners
, listener
);
641 enum bt_graph_status
bt_graph_add_port_added_listener(
642 struct bt_graph
*graph
,
643 bt_graph_port_added_listener listener
, void *data
)
645 enum bt_graph_status status
= BT_GRAPH_STATUS_OK
;
647 if (!graph
|| !listener
) {
648 status
= BT_GRAPH_STATUS_INVALID
;
652 add_listener(graph
->listeners
.port_added
, listener
, data
);
658 enum bt_graph_status
bt_graph_add_port_removed_listener(
659 struct bt_graph
*graph
,
660 bt_graph_port_removed_listener listener
, void *data
)
662 enum bt_graph_status status
= BT_GRAPH_STATUS_OK
;
664 if (!graph
|| !listener
) {
665 status
= BT_GRAPH_STATUS_INVALID
;
669 add_listener(graph
->listeners
.port_removed
, listener
, data
);
675 enum bt_graph_status
bt_graph_add_ports_connected_listener(
676 struct bt_graph
*graph
,
677 bt_graph_ports_connected_listener listener
, void *data
)
679 enum bt_graph_status status
= BT_GRAPH_STATUS_OK
;
681 if (!graph
|| !listener
) {
682 status
= BT_GRAPH_STATUS_INVALID
;
686 add_listener(graph
->listeners
.ports_connected
, listener
, data
);
692 enum bt_graph_status
bt_graph_add_ports_disconnected_listener(
693 struct bt_graph
*graph
,
694 bt_graph_ports_disconnected_listener listener
, void *data
)
696 enum bt_graph_status status
= BT_GRAPH_STATUS_OK
;
698 if (!graph
|| !listener
) {
699 status
= BT_GRAPH_STATUS_INVALID
;
703 add_listener(graph
->listeners
.ports_disconnected
, listener
, data
);
710 void bt_graph_notify_port_added(struct bt_graph
*graph
, struct bt_port
*port
)
714 for (i
= 0; i
< graph
->listeners
.port_added
->len
; i
++) {
715 struct bt_graph_listener listener
=
716 g_array_index(graph
->listeners
.port_added
,
717 struct bt_graph_listener
, i
);
718 bt_graph_port_added_listener func
= listener
.func
;
721 func(port
, listener
.data
);
726 void bt_graph_notify_port_removed(struct bt_graph
*graph
,
727 struct bt_component
*comp
, struct bt_port
*port
)
731 for (i
= 0; i
< graph
->listeners
.port_removed
->len
; i
++) {
732 struct bt_graph_listener listener
=
733 g_array_index(graph
->listeners
.port_removed
,
734 struct bt_graph_listener
, i
);
735 bt_graph_port_removed_listener func
= listener
.func
;
738 func(comp
, port
, listener
.data
);
743 void bt_graph_notify_ports_connected(struct bt_graph
*graph
,
744 struct bt_port
*upstream_port
, struct bt_port
*downstream_port
)
748 for (i
= 0; i
< graph
->listeners
.ports_connected
->len
; i
++) {
749 struct bt_graph_listener listener
=
750 g_array_index(graph
->listeners
.ports_connected
,
751 struct bt_graph_listener
, i
);
752 bt_graph_ports_connected_listener func
= listener
.func
;
755 func(upstream_port
, downstream_port
, listener
.data
);
760 void bt_graph_notify_ports_disconnected(struct bt_graph
*graph
,
761 struct bt_component
*upstream_comp
,
762 struct bt_component
*downstream_comp
,
763 struct bt_port
*upstream_port
, struct bt_port
*downstream_port
)
767 for (i
= 0; i
< graph
->listeners
.ports_disconnected
->len
; i
++) {
768 struct bt_graph_listener listener
=
769 g_array_index(graph
->listeners
.ports_disconnected
,
770 struct bt_graph_listener
, i
);
771 bt_graph_ports_disconnected_listener func
= listener
.func
;
774 func(upstream_comp
, downstream_comp
, upstream_port
,
775 downstream_port
, listener
.data
);