/*
- * connection.c
- *
- * Babeltrace Connection
- *
+ * Copyright 2017-2018 Philippe Proulx <pproulx@efficios.com>
* Copyright 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
*
- * Author: Jérémie Galarneau <jeremie.galarneau@efficios.com>
- *
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* SOFTWARE.
*/
+#define BT_LOG_TAG "CONNECTION"
+#include <babeltrace/lib-logging-internal.h>
+
#include <babeltrace/graph/notification-iterator-internal.h>
#include <babeltrace/graph/component-internal.h>
-#include <babeltrace/graph/component-source-internal.h>
-#include <babeltrace/graph/component-filter-internal.h>
#include <babeltrace/graph/connection-internal.h>
-#include <babeltrace/graph/private-connection.h>
+#include <babeltrace/graph/connection-const.h>
#include <babeltrace/graph/graph-internal.h>
#include <babeltrace/graph/port-internal.h>
#include <babeltrace/object-internal.h>
#include <babeltrace/compiler-internal.h>
+#include <babeltrace/object.h>
+#include <babeltrace/assert-internal.h>
+#include <babeltrace/assert-pre-internal.h>
+#include <stdlib.h>
#include <glib.h>
static
-void bt_connection_destroy(struct bt_object *obj)
+void destroy_connection(struct bt_object *obj)
{
struct bt_connection *connection = container_of(obj,
struct bt_connection, base);
+ BT_LIB_LOGD("Destroying connection: %!+x", connection);
+
/*
- * No bt_put on ports as a connection only holds _weak_ references
- * to them.
+ * Make sure that each notification iterator which was created
+ * for this connection is finalized before we destroy it. Once a
+ * notification iterator is finalized, all its method return
+ * NULL or the BT_NOTIFICATION_ITERATOR_STATUS_CANCELED status.
+ *
+ * Because connections are destroyed before components within a
+ * graph, this ensures that notification iterators are always
+ * finalized before their upstream component.
+ *
+ * Ending the connection does exactly this. We pass `false` to
+ * bt_connection_end() here to avoid removing this connection
+ * from the graph: if we're here, we're already in the graph's
+ * destructor.
+ */
+ bt_connection_end(connection, false);
+ g_ptr_array_free(connection->iterators, TRUE);
+ connection->iterators = NULL;
+
+ /*
+ * No bt_object_put_ref on ports as a connection only holds _weak_
+ * references to them.
*/
g_free(connection);
}
-struct bt_connection *bt_connection_from_private_connection(
- struct bt_private_connection *private_connection)
+static
+void try_remove_connection_from_graph(struct bt_connection *connection)
+{
+ void *graph = (void *) bt_object_borrow_parent(&connection->base);
+
+ if (connection->base.ref_count > 0 ||
+ connection->downstream_port ||
+ connection->upstream_port ||
+ connection->iterators->len > 0) {
+ return;
+ }
+
+ /*
+ * At this point we know that:
+ *
+ * 1. The connection is ended (ports were disconnected).
+ * 2. All the notification iterators that this connection
+ * created, if any, are finalized.
+ * 3. The connection's reference count is 0, so only the
+ * parent (graph) owns this connection after this call.
+ *
+ * In other words, no other object than the graph knows this
+ * connection.
+ *
+ * It is safe to remove the connection from the graph, therefore
+ * destroying it.
+ */
+ BT_LIB_LOGD("Removing self from graph's connections: "
+ "%![graph-]+g, %![conn-]+x", graph, connection);
+ bt_graph_remove_connection(graph, connection);
+}
+
+static
+void parent_is_owner(struct bt_object *obj)
{
- return bt_get(bt_connection_from_private(private_connection));
+ struct bt_connection *connection = container_of(obj,
+ struct bt_connection, base);
+
+ try_remove_connection_from_graph(connection);
}
BT_HIDDEN
-struct bt_connection *bt_connection_create(
- struct bt_graph *graph,
+struct bt_connection *bt_connection_create(struct bt_graph *graph,
struct bt_port *upstream_port,
struct bt_port *downstream_port)
{
struct bt_connection *connection = NULL;
- if (bt_port_get_type(upstream_port) != BT_PORT_TYPE_OUTPUT) {
- goto end;
- }
- if (bt_port_get_type(downstream_port) != BT_PORT_TYPE_INPUT) {
+ BT_LIB_LOGD("Creating connection: "
+ "%![graph-]+g, %![up-port-]+p, %![down-port-]+p",
+ graph, upstream_port, downstream_port);
+ connection = g_new0(struct bt_connection, 1);
+ if (!connection) {
+ BT_LOGE_STR("Failed to allocate one connection.");
goto end;
}
- connection = g_new0(struct bt_connection, 1);
- if (!connection) {
+ bt_object_init_shared_with_parent(&connection->base,
+ destroy_connection);
+ bt_object_set_parent_is_owner_listener_func(&connection->base,
+ parent_is_owner);
+ connection->iterators = g_ptr_array_new();
+ if (!connection->iterators) {
+ BT_LOGE_STR("Failed to allocate a GPtrArray.");
+ BT_OBJECT_PUT_REF_AND_RESET(connection);
goto end;
}
- bt_object_init(connection, bt_connection_destroy);
/* Weak references are taken, see comment in header. */
connection->upstream_port = upstream_port;
connection->downstream_port = downstream_port;
+ BT_LIB_LOGD("Setting upstream port's connection: %!+p", upstream_port);
bt_port_set_connection(upstream_port, connection);
+ BT_LIB_LOGD("Setting downstream port's connection: %!+p",
+ downstream_port);
bt_port_set_connection(downstream_port, connection);
- bt_object_set_parent(connection, &graph->base);
+ bt_object_set_parent(&connection->base, &graph->base);
+ BT_LIB_LOGD("Created connection: %!+x", connection);
+
end:
return connection;
}
BT_HIDDEN
-void bt_connection_disconnect_ports(struct bt_connection *conn)
+void bt_connection_end(struct bt_connection *conn, bool try_remove_from_graph)
{
struct bt_component *downstream_comp = NULL;
struct bt_component *upstream_comp = NULL;
struct bt_port *downstream_port = conn->downstream_port;
struct bt_port *upstream_port = conn->upstream_port;
- struct bt_graph *graph = (void *) bt_object_get_parent(conn);
+ struct bt_graph *graph = bt_connection_borrow_graph(conn);
+ size_t i;
+
+ BT_LIB_LOGD("Ending connection: %!+x, try-remove-from-graph=%d",
+ conn, try_remove_from_graph);
+
+ /*
+ * Any of the following notification callback functions could
+ * remove one of the connection's ports from its component. To
+ * make sure that at least logging in called functions works
+ * with existing objects, get a local reference on both ports.
+ */
+ bt_object_get_ref(downstream_port);
+ bt_object_get_ref(upstream_port);
if (downstream_port) {
- downstream_comp = bt_port_get_component(downstream_port);
+ BT_LIB_LOGD("Disconnecting connection's downstream port: %!+p",
+ downstream_port);
+ downstream_comp = bt_port_borrow_component_inline(
+ downstream_port);
bt_port_set_connection(downstream_port, NULL);
conn->downstream_port = NULL;
}
if (upstream_port) {
- upstream_comp = bt_port_get_component(upstream_port);
+ BT_LIB_LOGD("Disconnecting connection's upstream port: %!+p",
+ upstream_port);
+ upstream_comp = bt_port_borrow_component_inline(
+ upstream_port);
bt_port_set_connection(upstream_port, NULL);
conn->upstream_port = NULL;
}
- if (downstream_comp) {
+ if (downstream_comp && conn->notified_downstream_port_connected &&
+ !conn->notified_downstream_port_disconnected) {
+ /* bt_component_port_disconnected() logs details */
bt_component_port_disconnected(downstream_comp,
downstream_port);
+ conn->notified_downstream_port_disconnected = true;
}
- if (upstream_comp) {
+ if (upstream_comp && conn->notified_upstream_port_connected &&
+ !conn->notified_upstream_port_disconnected) {
+ /* bt_component_port_disconnected() logs details */
bt_component_port_disconnected(upstream_comp, upstream_port);
+ conn->notified_upstream_port_disconnected = true;
}
- assert(graph);
- bt_graph_notify_ports_disconnected(graph, upstream_comp,
- downstream_comp, upstream_port, downstream_port);
- bt_put(downstream_comp);
- bt_put(upstream_comp);
- bt_put(graph);
-}
+ BT_ASSERT(graph);
-struct bt_port *bt_connection_get_upstream_port(
- struct bt_connection *connection)
-{
- return connection ? bt_get(connection->upstream_port) : NULL;
-}
-
-struct bt_port *bt_connection_get_downstream_port(
- struct bt_connection *connection)
-{
- return connection ? bt_get(connection->downstream_port) : NULL;
-}
-
-struct bt_notification_iterator *
-bt_private_connection_create_notification_iterator(
- struct bt_private_connection *private_connection)
-{
- enum bt_notification_iterator_status ret_iterator;
- enum bt_component_class_type upstream_comp_class_type;
- struct bt_notification_iterator *iterator = NULL;
- struct bt_port *upstream_port = NULL;
- struct bt_component *upstream_component = NULL;
- struct bt_component_class *upstream_comp_class = NULL;
- struct bt_connection *connection = NULL;
- bt_component_class_notification_iterator_init_method init_method = NULL;
-
- if (!private_connection) {
- goto error;
- }
-
- connection = bt_connection_from_private(private_connection);
-
- if (!connection->upstream_port || !connection->downstream_port) {
- goto error;
+ if (conn->notified_graph_ports_connected &&
+ !conn->notified_graph_ports_disconnected) {
+ /* bt_graph_notify_ports_disconnected() logs details */
+ bt_graph_notify_ports_disconnected(graph, upstream_comp,
+ downstream_comp, upstream_port, downstream_port);
+ conn->notified_graph_ports_disconnected = true;
}
- upstream_port = connection->upstream_port;
- assert(upstream_port);
- upstream_component = bt_port_get_component(upstream_port);
- assert(upstream_component);
- upstream_comp_class = upstream_component->class;
+ /*
+ * It is safe to put the local port references now that we don't
+ * need them anymore. This could indeed destroy them.
+ */
+ bt_object_put_ref(downstream_port);
+ bt_object_put_ref(upstream_port);
- if (!upstream_component) {
- goto error;
- }
+ /*
+ * Because this connection is ended, finalize (cancel) each
+ * notification iterator created from it.
+ */
+ for (i = 0; i < conn->iterators->len; i++) {
+ struct bt_self_component_port_input_notification_iterator *iterator =
+ g_ptr_array_index(conn->iterators, i);
- upstream_comp_class_type =
- bt_component_get_class_type(upstream_component);
- if (upstream_comp_class_type != BT_COMPONENT_CLASS_TYPE_SOURCE &&
- upstream_comp_class_type != BT_COMPONENT_CLASS_TYPE_FILTER) {
- /* Unsupported operation. */
- goto error;
- }
+ BT_LIB_LOGD("Finalizing notification iterator created by "
+ "this ended connection: %![iter-]+i", iterator);
+ bt_self_component_port_input_notification_iterator_finalize(
+ iterator);
- iterator = bt_notification_iterator_create(upstream_component);
- if (!iterator) {
- goto error;
+ /*
+ * Make sure this iterator does not try to remove itself
+ * from this connection's iterators on destruction
+ * because this connection won't exist anymore.
+ */
+ bt_self_component_port_input_notification_iterator_set_connection(
+ iterator, NULL);
}
- switch (upstream_comp_class_type) {
- case BT_COMPONENT_CLASS_TYPE_SOURCE:
- {
- struct bt_component_class_source *source_class =
- container_of(upstream_comp_class,
- struct bt_component_class_source, parent);
- init_method = source_class->methods.iterator.init;
- break;
- }
- case BT_COMPONENT_CLASS_TYPE_FILTER:
- {
- struct bt_component_class_filter *filter_class =
- container_of(upstream_comp_class,
- struct bt_component_class_filter, parent);
- init_method = filter_class->methods.iterator.init;
- break;
- }
- default:
- /* Unreachable. */
- assert(0);
- }
+ g_ptr_array_set_size(conn->iterators, 0);
- if (init_method) {
- enum bt_notification_iterator_status status = init_method(
- bt_private_notification_iterator_from_notification_iterator(iterator),
- bt_private_port_from_port(upstream_port));
- if (status < 0) {
- goto error;
- }
+ if (try_remove_from_graph) {
+ try_remove_connection_from_graph(conn);
}
+}
- ret_iterator = bt_notification_iterator_validate(iterator);
- if (ret_iterator != BT_NOTIFICATION_ITERATOR_STATUS_OK) {
- goto error;
- }
+const struct bt_port_output *bt_connection_borrow_upstream_port_const(
+ const struct bt_connection *connection)
+{
+ BT_ASSERT_PRE_NON_NULL(connection, "Connection");
+ return (void *) connection->upstream_port;
+}
- goto end;
+const struct bt_port_input *bt_connection_borrow_downstream_port_const(
+ const struct bt_connection *connection)
+{
+ BT_ASSERT_PRE_NON_NULL(connection, "Connection");
+ return (void *) connection->downstream_port;
+}
-error:
- BT_PUT(iterator);
+BT_HIDDEN
+void bt_connection_remove_iterator(struct bt_connection *conn,
+ struct bt_self_component_port_input_notification_iterator *iterator)
+{
+ g_ptr_array_remove(conn->iterators, iterator);
+ BT_LIB_LOGV("Removed notification iterator from connection: "
+ "%![conn-]+x, %![iter-]+i", conn, iterator);
+ try_remove_connection_from_graph(conn);
+}
-end:
- bt_put(upstream_component);
- return iterator;
+bt_bool bt_connection_is_ended(const struct bt_connection *connection)
+{
+ return !connection->downstream_port && !connection->upstream_port;
}