/** * gst_bus_timed_pop_filtered: * @bus: a #GstBus to pop from * @timeout: a timeout in nanoseconds, or GST_CLOCK_TIME_NONE to wait forever * @types: message types to take into account, GST_MESSAGE_ANY for any type * * Get a message from the bus whose type matches the message type mask @types, * waiting up to the specified timeout (and discarding any messages that do not * match the mask provided). * * If @timeout is 0, this function behaves like gst_bus_pop_filtered(). If * @timeout is #GST_CLOCK_TIME_NONE, this function will block forever until a * matching message was posted on the bus. * * Returns: (transfer full) (nullable): a #GstMessage matching the * filter in @types, or %NULL if no matching message was found on * the bus until the timeout expired. The message is taken from * the bus and needs to be unreffed with gst_message_unref() after * usage. * * MT safe. */ GstMessage * gst_bus_timed_pop_filtered (GstBus * bus, GstClockTime timeout, GstMessageType types) { GstMessage *message; GTimeVal now, then; gboolean first_round = TRUE; GstClockTime elapsed = 0; g_return_val_if_fail (GST_IS_BUS (bus), NULL); g_return_val_if_fail (types != 0, NULL); g_return_val_if_fail (timeout == 0 || bus->priv->poll != NULL, NULL); g_mutex_lock (&bus->priv->queue_lock); while (TRUE) { gint ret; GST_LOG_OBJECT (bus, "have %d messages", gst_atomic_queue_length (bus->priv->queue)); while ((message = gst_atomic_queue_pop (bus->priv->queue))) { if (bus->priv->poll) { while (!gst_poll_read_control (bus->priv->poll)) { if (errno == EWOULDBLOCK) { /* Retry, this can happen if pushing to the queue has finished, * popping here succeeded but writing control did not finish * before we got to this line. */ /* Give other threads the chance to do something */ g_thread_yield (); continue; } else { /* This is a real error and means that either the bus is in an * inconsistent state, or the GstPoll is invalid. GstPoll already * prints a critical warning about this, no need to do that again * ourselves */ break; } } } GST_DEBUG_OBJECT (bus, "got message %p, %s from %s, type mask is %u", message, GST_MESSAGE_TYPE_NAME (message), GST_MESSAGE_SRC_NAME (message), (guint) types); if ((GST_MESSAGE_TYPE (message) & types) != 0) { /* Extra check to ensure extended types don't get matched unless * asked for */ if ((!GST_MESSAGE_TYPE_IS_EXTENDED (message)) || (types & GST_MESSAGE_EXTENDED)) { /* exit the loop, we have a message */ goto beach; } } GST_DEBUG_OBJECT (bus, "discarding message, does not match mask"); gst_message_unref (message); message = NULL; } /* no need to wait, exit loop */ if (timeout == 0) break; else if (timeout != GST_CLOCK_TIME_NONE) { if (first_round) { g_get_current_time (&then); first_round = FALSE; } else { g_get_current_time (&now); elapsed = GST_TIMEVAL_TO_TIME (now) - GST_TIMEVAL_TO_TIME (then); if (elapsed > timeout) break; } } /* only here in timeout case */ g_assert (bus->priv->poll); g_mutex_unlock (&bus->priv->queue_lock); ret = gst_poll_wait (bus->priv->poll, timeout - elapsed); g_mutex_lock (&bus->priv->queue_lock); if (ret == 0) { GST_INFO_OBJECT (bus, "timed out, breaking loop"); break; } else { GST_INFO_OBJECT (bus, "we got woken up, recheck for message"); } } beach: g_mutex_unlock (&bus->priv->queue_lock); return message; }
/** * gst_bus_timed_pop_filtered: * @bus: a #GstBus to pop from * @timeout: a timeout in nanoseconds, or GST_CLOCK_TIME_NONE to wait forever * @types: message types to take into account, GST_MESSAGE_ANY for any type * * Get a message from the bus whose type matches the message type mask @types, * waiting up to the specified timeout (and discarding any messages that do not * match the mask provided). * * If @timeout is 0, this function behaves like gst_bus_pop_filtered(). If * @timeout is #GST_CLOCK_TIME_NONE, this function will block forever until a * matching message was posted on the bus. * * Returns: (transfer full) (nullable): a #GstMessage matching the * filter in @types, or %NULL if no matching message was found on * the bus until the timeout expired. The message is taken from * the bus and needs to be unreffed with gst_message_unref() after * usage. * * MT safe. */ GstMessage * gst_bus_timed_pop_filtered (GstBus * bus, GstClockTime timeout, GstMessageType types) { GstMessage *message; GTimeVal now, then; gboolean first_round = TRUE; GstClockTime elapsed = 0; g_return_val_if_fail (GST_IS_BUS (bus), NULL); g_return_val_if_fail (types != 0, NULL); g_return_val_if_fail (timeout == 0 || bus->priv->poll != NULL, NULL); g_mutex_lock (&bus->priv->queue_lock); while (TRUE) { gint ret; GST_LOG_OBJECT (bus, "have %d messages", gst_atomic_queue_length (bus->priv->queue)); while ((message = gst_atomic_queue_pop (bus->priv->queue))) { if (bus->priv->poll) gst_poll_read_control (bus->priv->poll); GST_DEBUG_OBJECT (bus, "got message %p, %s from %s, type mask is %u", message, GST_MESSAGE_TYPE_NAME (message), GST_MESSAGE_SRC_NAME (message), (guint) types); if ((GST_MESSAGE_TYPE (message) & types) != 0) { /* Extra check to ensure extended types don't get matched unless * asked for */ if ((!GST_MESSAGE_TYPE_IS_EXTENDED (message)) || (types & GST_MESSAGE_EXTENDED)) { /* exit the loop, we have a message */ goto beach; } } GST_DEBUG_OBJECT (bus, "discarding message, does not match mask"); gst_message_unref (message); message = NULL; } /* no need to wait, exit loop */ if (timeout == 0) break; else if (timeout != GST_CLOCK_TIME_NONE) { if (first_round) { g_get_current_time (&then); first_round = FALSE; } else { g_get_current_time (&now); elapsed = GST_TIMEVAL_TO_TIME (now) - GST_TIMEVAL_TO_TIME (then); if (elapsed > timeout) break; } } /* only here in timeout case */ g_assert (bus->priv->poll); g_mutex_unlock (&bus->priv->queue_lock); ret = gst_poll_wait (bus->priv->poll, timeout - elapsed); g_mutex_lock (&bus->priv->queue_lock); if (ret == 0) { GST_INFO_OBJECT (bus, "timed out, breaking loop"); break; } else { GST_INFO_OBJECT (bus, "we got woken up, recheck for message"); } } beach: g_mutex_unlock (&bus->priv->queue_lock); return message; }