lib/graph/connection.c

   1 /*
   2  * connection.c
   3  *
   4  * Babeltrace Connection
   5  *
   6  * Copyright 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   7  *
   8  * Author: Jérémie Galarneau <jeremie.galarneau@efficios.com>
   9  *
  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:
  16  *
  17  * The above copyright notice and this permission notice shall be included in
  18  * all copies or substantial portions of the Software.
  19  *
  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
  26  * SOFTWARE.
  27  */
  28
  29 #include <babeltrace/graph/notification-iterator-internal.h>
  30 #include <babeltrace/graph/component-internal.h>
  31 #include <babeltrace/graph/component-source-internal.h>
  32 #include <babeltrace/graph/component-filter-internal.h>
  33 #include <babeltrace/graph/connection-internal.h>
  34 #include <babeltrace/graph/private-connection.h>
  35 #include <babeltrace/graph/graph-internal.h>
  36 #include <babeltrace/graph/port-internal.h>
  37 #include <babeltrace/object-internal.h>
  38 #include <babeltrace/compiler-internal.h>
  39 #include <glib.h>
  40
  41 static
  42 void bt_connection_destroy(struct bt_object *obj)
  43 {
  44         struct bt_connection *connection = container_of(obj,
  45                         struct bt_connection, base);
  46         size_t i;
  47
  48         /*
  49          * Make sure that each notification iterator which was created
  50          * for this connection is finalized before we destroy it. Once a
  51          * notification iterator is finalized, all its method return
  52          * NULL or the BT_NOTIFICATION_ITERATOR_STATUS_CANCELED status.
  53          *
  54          * Because connections are destroyed before components within a
  55          * graph, this ensures that notification iterators are always
  56          * finalized before their upstream component.
  57          */
  58         if (connection->iterators) {
  59                 for (i = 0; i < connection->iterators->len; i++) {
  60                         struct bt_notification_iterator *iterator =
  61                                 g_ptr_array_index(connection->iterators, i);
  62
  63                         bt_notification_iterator_finalize(iterator);
  64
  65                         /*
  66                          * Make sure this iterator does not try to
  67                          * remove itself from this connection's
  68                          * iterators on destruction because this
  69                          * connection won't exist anymore.
  70                          */
  71                         bt_notification_iterator_set_connection(iterator,
  72                                 NULL);
  73                 }
  74
  75                 g_ptr_array_free(connection->iterators, TRUE);
  76         }
  77
  78         /*
  79          * No bt_put on ports as a connection only holds _weak_ references
  80          * to them.
  81          */
  82         g_free(connection);
  83 }
  84
  85 struct bt_connection *bt_connection_from_private_connection(
  86                 struct bt_private_connection *private_connection)
  87 {
  88         return bt_get(bt_connection_from_private(private_connection));
  89 }
  90
  91 BT_HIDDEN
  92 struct bt_connection *bt_connection_create(
  93                 struct bt_graph *graph,
  94                 struct bt_port *upstream_port,
  95                 struct bt_port *downstream_port)
  96 {
  97         struct bt_connection *connection = NULL;
  98
  99         if (bt_port_get_type(upstream_port) != BT_PORT_TYPE_OUTPUT) {
 100                 goto end;
 101         }
 102         if (bt_port_get_type(downstream_port) != BT_PORT_TYPE_INPUT) {
 103                 goto end;
 104         }
 105
 106         connection = g_new0(struct bt_connection, 1);
 107         if (!connection) {
 108                 goto end;
 109         }
 110
 111         bt_object_init(connection, bt_connection_destroy);
 112         connection->iterators = g_ptr_array_new();
 113         if (!connection->iterators) {
 114                 BT_PUT(connection);
 115                 goto end;
 116         }
 117
 118         /* Weak references are taken, see comment in header. */
 119         connection->upstream_port = upstream_port;
 120         connection->downstream_port = downstream_port;
 121         bt_port_set_connection(upstream_port, connection);
 122         bt_port_set_connection(downstream_port, connection);
 123         bt_object_set_parent(connection, &graph->base);
 124 end:
 125         return connection;
 126 }
 127
 128 BT_HIDDEN
 129 void bt_connection_disconnect_ports(struct bt_connection *conn)
 130 {
 131         struct bt_component *downstream_comp = NULL;
 132         struct bt_component *upstream_comp = NULL;
 133         struct bt_port *downstream_port = conn->downstream_port;
 134         struct bt_port *upstream_port = conn->upstream_port;
 135         struct bt_graph *graph = (void *) bt_object_get_parent(conn);
 136
 137         if (downstream_port) {
 138                 downstream_comp = bt_port_get_component(downstream_port);
 139                 bt_port_set_connection(downstream_port, NULL);
 140                 conn->downstream_port = NULL;
 141         }
 142
 143         if (upstream_port) {
 144                 upstream_comp = bt_port_get_component(upstream_port);
 145                 bt_port_set_connection(upstream_port, NULL);
 146                 conn->upstream_port = NULL;
 147         }
 148
 149         if (downstream_comp) {
 150                 bt_component_port_disconnected(downstream_comp,
 151                         downstream_port);
 152         }
 153
 154         if (upstream_comp) {
 155                 bt_component_port_disconnected(upstream_comp, upstream_port);
 156         }
 157
 158         assert(graph);
 159         bt_graph_notify_ports_disconnected(graph, upstream_comp,
 160                 downstream_comp, upstream_port, downstream_port);
 161         bt_put(downstream_comp);
 162         bt_put(upstream_comp);
 163         bt_put(graph);
 164 }
 165
 166 struct bt_port *bt_connection_get_upstream_port(
 167                 struct bt_connection *connection)
 168 {
 169         return connection ? bt_get(connection->upstream_port) : NULL;
 170 }
 171
 172 struct bt_port *bt_connection_get_downstream_port(
 173                 struct bt_connection *connection)
 174 {
 175         return connection ? bt_get(connection->downstream_port) : NULL;
 176 }
 177
 178 struct bt_notification_iterator *
 179 bt_private_connection_create_notification_iterator(
 180                 struct bt_private_connection *private_connection,
 181                 const enum bt_notification_type *notification_types)
 182 {
 183         enum bt_notification_iterator_status ret_iterator;
 184         enum bt_component_class_type upstream_comp_class_type;
 185         struct bt_notification_iterator *iterator = NULL;
 186         struct bt_port *upstream_port = NULL;
 187         struct bt_component *upstream_component = NULL;
 188         struct bt_component_class *upstream_comp_class = NULL;
 189         struct bt_connection *connection = NULL;
 190         bt_component_class_notification_iterator_init_method init_method = NULL;
 191         static const enum bt_notification_type all_notif_types[] = {
 192                 BT_NOTIFICATION_TYPE_ALL,
 193                 BT_NOTIFICATION_TYPE_SENTINEL,
 194         };
 195
 196         if (!private_connection) {
 197                 goto error;
 198         }
 199
 200         if (!notification_types) {
 201                 notification_types = all_notif_types;
 202         }
 203
 204         connection = bt_connection_from_private(private_connection);
 205         if (!connection->upstream_port || !connection->downstream_port) {
 206                 goto error;
 207         }
 208
 209         upstream_port = connection->upstream_port;
 210         assert(upstream_port);
 211         upstream_component = bt_port_get_component(upstream_port);
 212         assert(upstream_component);
 213         upstream_comp_class = upstream_component->class;
 214
 215         if (!upstream_component) {
 216                 goto error;
 217         }
 218
 219         upstream_comp_class_type =
 220                 bt_component_get_class_type(upstream_component);
 221         if (upstream_comp_class_type != BT_COMPONENT_CLASS_TYPE_SOURCE &&
 222                         upstream_comp_class_type != BT_COMPONENT_CLASS_TYPE_FILTER) {
 223                 /* Unsupported operation. */
 224                 goto error;
 225         }
 226
 227         iterator = bt_notification_iterator_create(upstream_component,
 228                 upstream_port, notification_types, connection);
 229         if (!iterator) {
 230                 goto error;
 231         }
 232
 233         switch (upstream_comp_class_type) {
 234         case BT_COMPONENT_CLASS_TYPE_SOURCE:
 235         {
 236                 struct bt_component_class_source *source_class =
 237                         container_of(upstream_comp_class,
 238                                 struct bt_component_class_source, parent);
 239                 init_method = source_class->methods.iterator.init;
 240                 break;
 241         }
 242         case BT_COMPONENT_CLASS_TYPE_FILTER:
 243         {
 244                 struct bt_component_class_filter *filter_class =
 245                         container_of(upstream_comp_class,
 246                                 struct bt_component_class_filter, parent);
 247                 init_method = filter_class->methods.iterator.init;
 248                 break;
 249         }
 250         default:
 251                 /* Unreachable. */
 252                 assert(0);
 253         }
 254
 255         if (init_method) {
 256                 enum bt_notification_iterator_status status = init_method(
 257                         bt_private_notification_iterator_from_notification_iterator(iterator),
 258                         bt_private_port_from_port(upstream_port));
 259                 if (status < 0) {
 260                         goto error;
 261                 }
 262         }
 263
 264         ret_iterator = bt_notification_iterator_validate(iterator);
 265         if (ret_iterator != BT_NOTIFICATION_ITERATOR_STATUS_OK) {
 266                 goto error;
 267         }
 268
 269         g_ptr_array_add(connection->iterators, iterator);
 270         goto end;
 271
 272 error:
 273         BT_PUT(iterator);
 274
 275 end:
 276         bt_put(upstream_component);
 277         return iterator;
 278 }
 279
 280 BT_HIDDEN
 281 void bt_connection_remove_iterator(struct bt_connection *conn,
 282                 struct bt_notification_iterator *iterator)
 283 {
 284         g_ptr_array_remove(conn->iterators, iterator);
 285 }