static void dump_kaleidoscope_head(struct kaleidoscope_head *khp)
{
printf("Kaleidoscope head %p egi: %#lx %c%c add: %p remove: %p free: %p\n",
khp, khp->kh_kgi,
"L."[!!cds_list_empty(&khp->kh_list)],
".G"[!!khp->kh_gone],
khp->kh_add, khp->kh_remove, khp->kh_free);
}
struct cds_list_head *deq_pop_r(struct deq *p)
{
struct cds_list_head *e;
if (cds_list_empty(&p->chain))
e = NULL;
else {
e = p->chain.next;
cds_list_del(e);
CDS_INIT_LIST_HEAD(e);
}
return e;
}
struct cds_list_head *deq_pop_l(struct deq *p)
{
struct cds_list_head *e;
spin_lock(&p->lock);
if (cds_list_empty(&p->chain))
e = NULL;
else {
e = p->chain.prev;
cds_list_del(e);
CDS_INIT_LIST_HEAD(e);
}
spin_unlock(&p->lock);
return e;
}
enum lttng_notification_channel_status
lttng_notification_channel_get_next_notification(
struct lttng_notification_channel *channel,
struct lttng_notification **_notification)
{
int ret;
struct lttng_notification *notification = NULL;
enum lttng_notification_channel_status status =
LTTNG_NOTIFICATION_CHANNEL_STATUS_OK;
if (!channel || !_notification) {
status = LTTNG_NOTIFICATION_CHANNEL_STATUS_INVALID;
goto end;
}
if (channel->pending_notifications.count) {
struct pending_notification *pending_notification;
assert(!cds_list_empty(&channel->pending_notifications.list));
/* Deliver one of the pending notifications. */
pending_notification = cds_list_first_entry(
&channel->pending_notifications.list,
struct pending_notification,
node);
notification = pending_notification->notification;
if (!notification) {
status = LTTNG_NOTIFICATION_CHANNEL_STATUS_NOTIFICATIONS_DROPPED;
}
cds_list_del(&pending_notification->node);
channel->pending_notifications.count--;
free(pending_notification);
goto end;
}
pthread_mutex_lock(&channel->lock);
ret = receive_message(channel);
if (ret) {
status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR;
goto end_unlock;
}
switch (get_current_message_type(channel)) {
case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION:
notification = create_notification_from_current_message(
channel);
if (!notification) {
status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR;
goto end_unlock;
}
break;
case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION_DROPPED:
/* No payload to consume. */
status = LTTNG_NOTIFICATION_CHANNEL_STATUS_NOTIFICATIONS_DROPPED;
break;
default:
/* Protocol error. */
status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR;
goto end_unlock;
}
end_unlock:
pthread_mutex_unlock(&channel->lock);
end:
if (_notification) {
*_notification = notification;
}
return status;
}
