/**
* 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;
}
