simplify events and commands

25 files changed, 216 insertions, 248 deletions

diff --git a/pinos/client/connection.c b/pinos/client/connection.c
index e6254889..eb92d315 100644
--- a/pinos/client/connection.c
+++ b/pinos/client/connection.c
@@ -140,8 +140,6 @@ connection_parse_node_event (PinosConnection *conn, PinosControlCmdNodeEvent *cm
   memcpy (cmd, p, sizeof (PinosControlCmdNodeEvent));
   if (cmd->event)
     cmd->event = SPA_MEMBER (p, SPA_PTR_TO_INT (cmd->event), SpaNodeEvent);
-  if (cmd->event->data)
-    cmd->event->data = SPA_MEMBER (p, SPA_PTR_TO_INT (cmd->event->data), void);
 }
 
 static void
@@ -151,8 +149,6 @@ connection_parse_node_command (PinosConnection *conn, PinosControlCmdNodeCommand
   memcpy (cmd, p, sizeof (PinosControlCmdNodeCommand));
   if (cmd->command)
     cmd->command = SPA_MEMBER (p, SPA_PTR_TO_INT (cmd->command), SpaNodeCommand);
-  if (cmd->command->data)
-    cmd->command->data = SPA_MEMBER (p, SPA_PTR_TO_INT (cmd->command->data), void);
 }
 
 static void *
@@ -331,11 +327,9 @@ connection_add_node_event (PinosConnection *conn, PinosControlCmdNodeEvent *ev)
   size_t len;
   void *p;
   PinosControlCmdNodeEvent *d;
-  SpaNodeEvent *ne;
 
   /* calculate length */
   len = sizeof (PinosControlCmdNodeEvent);
-  len += sizeof (SpaNodeEvent);
   len += ev->event->size;
 
   p = connection_add_cmd (conn, PINOS_CONTROL_CMD_NODE_EVENT, len);
@@ -345,25 +339,18 @@ connection_add_node_event (PinosConnection *conn, PinosControlCmdNodeEvent *ev)
   p = SPA_MEMBER (d, sizeof (PinosControlCmdNodeEvent), void);
   d->event = SPA_INT_TO_PTR (SPA_PTRDIFF (p, d));
 
-  ne = p;
-  memcpy (p, ev->event, sizeof (SpaNodeEvent));
-  p = SPA_MEMBER (p, sizeof (SpaNodeEvent), void);
-  ne->data = SPA_INT_TO_PTR (SPA_PTRDIFF (p, d));
-  memcpy (p, ev->event->data, ev->event->size);
+  memcpy (p, ev->event, ev->event->size);
 }
 
-
 static void
 connection_add_node_command (PinosConnection *conn, PinosControlCmdNodeCommand *cm)
 {
   size_t len;
   void *p;
   PinosControlCmdNodeCommand *d;
-  SpaNodeCommand *nc;
 
   /* calculate length */
   len = sizeof (PinosControlCmdNodeCommand);
-  len += sizeof (SpaNodeCommand);
   len += cm->command->size;
 
   p = connection_add_cmd (conn, PINOS_CONTROL_CMD_NODE_COMMAND, len);
@@ -373,11 +360,7 @@ connection_add_node_command (PinosConnection *conn, PinosControlCmdNodeCommand *
   p = SPA_MEMBER (d, sizeof (PinosControlCmdNodeCommand), void);
   d->command = SPA_INT_TO_PTR (SPA_PTRDIFF (p, d));
 
-  nc = p;
-  memcpy (p, cm->command, sizeof (SpaNodeCommand));
-  p = SPA_MEMBER (p, sizeof (SpaNodeCommand), void);
-  nc->data = SPA_INT_TO_PTR (SPA_PTRDIFF (p, d));
-  memcpy (p, cm->command->data, cm->command->size);
+  memcpy (p, cm->command, cm->command->size);
 }
 
 static gboolean
diff --git a/pinos/client/stream.c b/pinos/client/stream.c
index 608619c0..3b6f5675 100644
--- a/pinos/client/stream.c
+++ b/pinos/client/stream.c
@@ -665,13 +665,11 @@ send_need_input (PinosStream *stream, uint32_t port_id)
 {
   PinosStreamPrivate *priv = stream->priv;
   PinosControlCmdNodeEvent cne;
-  SpaNodeEvent ne;
   SpaNodeEventNeedInput ni;
 
-  cne.event = ≠
-  ne.type = SPA_NODE_EVENT_TYPE_NEED_INPUT;
-  ne.data = ∋
-  ne.size = sizeof (ni);
+  cne.event = &ni.event;
+  ni.event.type = SPA_NODE_EVENT_TYPE_NEED_INPUT;
+  ni.event.size = sizeof (ni);
   ni.port_id = port_id;
   pinos_connection_add_cmd (priv->rtconn, PINOS_CONTROL_CMD_NODE_EVENT, &cne);
 
@@ -684,13 +682,11 @@ add_request_clock_update (PinosStream *stream)
 {
   PinosStreamPrivate *priv = stream->priv;
   PinosControlCmdNodeEvent cne;
-  SpaNodeEvent ne;
   SpaNodeEventRequestClockUpdate rcu;
 
-  cne.event = ≠
-  ne.type = SPA_NODE_EVENT_TYPE_REQUEST_CLOCK_UPDATE;
-  ne.data = &rcu;
-  ne.size = sizeof (rcu);
+  cne.event = &rcu.event;
+  rcu.event.type = SPA_NODE_EVENT_TYPE_REQUEST_CLOCK_UPDATE;
+  rcu.event.size = sizeof (rcu);
   rcu.update_mask = SPA_NODE_EVENT_REQUEST_CLOCK_UPDATE_TIME;
   rcu.timestamp = 0;
   rcu.offset = 0;
@@ -704,13 +700,11 @@ add_async_complete (PinosStream       *stream,
 {
   PinosStreamPrivate *priv = stream->priv;
   PinosControlCmdNodeEvent cne;
-  SpaNodeEvent ne;
   SpaNodeEventAsyncComplete ac;
 
-  cne.event = ≠
-  ne.type = SPA_NODE_EVENT_TYPE_ASYNC_COMPLETE;
-  ne.data = ∾
-  ne.size = sizeof (ac);
+  cne.event = &ac.event;
+  ac.event.type = SPA_NODE_EVENT_TYPE_ASYNC_COMPLETE;
+  ac.event.size = sizeof (ac);
   ac.seq = seq;
   ac.res = res;
   pinos_connection_add_cmd (priv->conn, PINOS_CONTROL_CMD_NODE_EVENT, &cne);
@@ -721,13 +715,11 @@ send_reuse_buffer (PinosStream *stream, uint32_t port_id, uint32_t buffer_id)
 {
   PinosStreamPrivate *priv = stream->priv;
   PinosControlCmdNodeEvent cne;
-  SpaNodeEvent ne;
   SpaNodeEventReuseBuffer rb;
 
-  cne.event = ≠
-  ne.type = SPA_NODE_EVENT_TYPE_REUSE_BUFFER;
-  ne.data = &rb;
-  ne.size = sizeof (rb);
+  cne.event = &rb.event;
+  rb.event.type = SPA_NODE_EVENT_TYPE_REUSE_BUFFER;
+  rb.event.size = sizeof (rb);
   rb.port_id = port_id;
   rb.buffer_id = buffer_id;
   pinos_connection_add_cmd (priv->rtconn, PINOS_CONTROL_CMD_NODE_EVENT, &cne);
@@ -742,7 +734,6 @@ send_process_buffer (PinosStream *stream, uint32_t port_id, uint32_t buffer_id)
   PinosStreamPrivate *priv = stream->priv;
   PinosControlCmdProcessBuffer pb;
   PinosControlCmdNodeEvent cne;
-  SpaNodeEvent ne;
   SpaNodeEventHaveOutput ho;
 
   pb.direction = priv->direction;
@@ -750,10 +741,9 @@ send_process_buffer (PinosStream *stream, uint32_t port_id, uint32_t buffer_id)
   pb.buffer_id = buffer_id;
   pinos_connection_add_cmd (priv->rtconn, PINOS_CONTROL_CMD_PROCESS_BUFFER, &pb);
 
-  cne.event = ≠
-  ne.type = SPA_NODE_EVENT_TYPE_HAVE_OUTPUT;
-  ne.data = &ho;
-  ne.size = sizeof (ho);
+  cne.event = &ho.event;
+  ho.event.type = SPA_NODE_EVENT_TYPE_HAVE_OUTPUT;
+  ho.event.size = sizeof (ho);
   ho.port_id = port_id;
   pinos_connection_add_cmd (priv->rtconn, PINOS_CONTROL_CMD_NODE_EVENT, &cne);
 
@@ -854,7 +844,7 @@ handle_rtnode_event (PinosStream  *stream,
 
     case SPA_NODE_EVENT_TYPE_REUSE_BUFFER:
     {
-      SpaNodeEventReuseBuffer *p = event->data;
+      SpaNodeEventReuseBuffer *p = (SpaNodeEventReuseBuffer *) event;
       BufferId *bid;
 
       if (p->port_id != priv->port_id)
@@ -924,7 +914,7 @@ handle_node_command (PinosStream    *stream,
 
     case SPA_NODE_COMMAND_CLOCK_UPDATE:
     {
-      SpaNodeCommandClockUpdate *cu = command->data;
+      SpaNodeCommandClockUpdate *cu = (SpaNodeCommandClockUpdate *) command;
       if (cu->flags & SPA_NODE_COMMAND_CLOCK_UPDATE_FLAG_LIVE) {
         pinos_properties_set (priv->properties,
                           "pinos.latency.is-live", "1");
diff --git a/pinos/modules/spa/spa-alsa-monitor.c b/pinos/modules/spa/spa-alsa-monitor.c
index 393b2e78..5a87d32f 100644
--- a/pinos/modules/spa/spa-alsa-monitor.c
+++ b/pinos/modules/spa/spa-alsa-monitor.c
@@ -176,18 +176,18 @@ on_monitor_event  (SpaMonitor      *monitor,
   switch (event->type) {
     case SPA_MONITOR_EVENT_TYPE_ADDED:
     {
-      SpaMonitorItem *item = event->data;
+      SpaMonitorItem *item = (SpaMonitorItem *) event;
       add_item (this, item);
       break;
     }
     case SPA_MONITOR_EVENT_TYPE_REMOVED:
     {
-      SpaMonitorItem *item = event->data;
+      SpaMonitorItem *item = (SpaMonitorItem *) event;
       remove_item (this, item);
     }
     case SPA_MONITOR_EVENT_TYPE_CHANGED:
     {
-      SpaMonitorItem *item = event->data;
+      SpaMonitorItem *item = (SpaMonitorItem *) event;
       g_debug ("alsa-monitor %p: changed: \"%s\"", this, item->name);
       break;
     }
diff --git a/pinos/modules/spa/spa-v4l2-monitor.c b/pinos/modules/spa/spa-v4l2-monitor.c
index 0f0d0139..06500c6c 100644
--- a/pinos/modules/spa/spa-v4l2-monitor.c
+++ b/pinos/modules/spa/spa-v4l2-monitor.c
@@ -177,18 +177,18 @@ on_monitor_event  (SpaMonitor      *monitor,
   switch (event->type) {
     case SPA_MONITOR_EVENT_TYPE_ADDED:
     {
-      SpaMonitorItem *item = event->data;
+      SpaMonitorItem *item = (SpaMonitorItem *) event;
       add_item (this, item);
       break;
     }
     case SPA_MONITOR_EVENT_TYPE_REMOVED:
     {
-      SpaMonitorItem *item = event->data;
+      SpaMonitorItem *item = (SpaMonitorItem *) event;
       remove_item (this, item);
     }
     case SPA_MONITOR_EVENT_TYPE_CHANGED:
     {
-      SpaMonitorItem *item = event->data;
+      SpaMonitorItem *item = (SpaMonitorItem *) event;
       g_debug ("v4l2-monitor %p: changed: \"%s\"", this, item->name);
       break;
     }
diff --git a/pinos/server/client-node.c b/pinos/server/client-node.c
index d1bcb378..4ae6b2ed 100644
--- a/pinos/server/client-node.c
+++ b/pinos/server/client-node.c
@@ -148,15 +148,13 @@ enum
 static void
 send_async_complete (SpaProxy *this, uint32_t seq, SpaResult res)
 {
-  SpaNodeEvent event;
   SpaNodeEventAsyncComplete ac;
 
-  event.type = SPA_NODE_EVENT_TYPE_ASYNC_COMPLETE;
-  event.data = ∾
-  event.size = sizeof (ac);
+  ac.event.type = SPA_NODE_EVENT_TYPE_ASYNC_COMPLETE;
+  ac.event.size = sizeof (ac);
   ac.seq = seq;
   ac.res = res;
-  this->event_cb (&this->node, &event, this->user_data);
+  this->event_cb (&this->node, &ac.event, this->user_data);
 }
 
 static SpaResult
@@ -220,8 +218,7 @@ spa_proxy_node_send_command (SpaNode        *node,
       if (!pinos_connection_flush (this->conn)) {
         spa_log_error (this->log, "proxy %p: error writing connection\n", this);
         res = SPA_RESULT_ERROR;
-      }
-      else
+      } else
         res = SPA_RESULT_RETURN_ASYNC (cnc.seq);
       break;
     }
@@ -238,7 +235,6 @@ spa_proxy_node_send_command (SpaNode        *node,
         spa_log_error (this->log, "proxy %p: error writing connection\n", this);
         res = SPA_RESULT_ERROR;
       }
-
       break;
     }
   }
@@ -960,7 +956,6 @@ spa_proxy_node_port_reuse_buffer (SpaNode         *node,
 {
   SpaProxy *this;
   PinosControlCmdNodeEvent cne;
-  SpaNodeEvent ne;
   SpaNodeEventReuseBuffer rb;
 
   if (node == NULL)
@@ -972,10 +967,9 @@ spa_proxy_node_port_reuse_buffer (SpaNode         *node,
     return SPA_RESULT_INVALID_PORT;
 
   /* send start */
-  cne.event = ≠
-  ne.type = SPA_NODE_EVENT_TYPE_REUSE_BUFFER;
-  ne.data = &rb;
-  ne.size = sizeof (rb);
+  cne.event = &rb.event;
+  rb.event.type = SPA_NODE_EVENT_TYPE_REUSE_BUFFER;
+  rb.event.size = sizeof (rb);
   rb.port_id = port_id;
   rb.buffer_id = buffer_id;
   pinos_connection_add_cmd (this->rtconn, PINOS_CONTROL_CMD_NODE_EVENT, &cne);
diff --git a/pinos/server/data-loop.c b/pinos/server/data-loop.c
index 3bff749d..8a1db6e2 100644
--- a/pinos/server/data-loop.c
+++ b/pinos/server/data-loop.c
@@ -157,7 +157,7 @@ loop (void *user_data)
       while (spa_ringbuffer_get_read_offset (&priv->buffer, &offset) > 0) {
         InvokeItem *item = SPA_MEMBER (priv->buffer_data, offset, InvokeItem);
         g_debug ("data-loop %p: invoke %d", this, item->seq);
-        item->func (p, item->seq, item->size, item->data, item->user_data);
+        item->func (p, true, item->seq, item->size, item->data, item->user_data);
         spa_ringbuffer_read_advance (&priv->buffer, item->item_size);
       }
       continue;
@@ -313,36 +313,43 @@ do_invoke (SpaPoll           *poll,
 {
   PinosDataLoop *this = SPA_CONTAINER_OF (poll, PinosDataLoop, poll);
   PinosDataLoopPrivate *priv = this->priv;
+  gboolean in_thread = pthread_equal (priv->thread, pthread_self());
   SpaRingbufferArea areas[2];
   InvokeItem *item;
+  SpaResult res;
 
-  spa_ringbuffer_get_write_areas (&priv->buffer, areas);
-  if (areas[0].len < sizeof (InvokeItem)) {
-    g_warning ("queue full");
-    return SPA_RESULT_ERROR;
-  }
-  item = SPA_MEMBER (priv->buffer_data, areas[0].offset, InvokeItem);
-  item->seq = seq;
-  item->func = func;
-  item->user_data = user_data;
-  item->size = size;
-
-  if (areas[0].len > sizeof (InvokeItem) + size) {
-    item->data = SPA_MEMBER (item, sizeof (InvokeItem), void);
-    item->item_size = sizeof (InvokeItem) + size;
-    if (areas[0].len < sizeof (InvokeItem) + item->item_size)
-      item->item_size = areas[0].len;
+  if (in_thread) {
+    res = func (poll, false, seq, size, data, user_data);
   } else {
-    item->data = SPA_MEMBER (priv->buffer_data, areas[1].offset, void);
-    item->item_size = areas[0].len + 1 + size;
-  }
-  memcpy (item->data, data, size);
+    spa_ringbuffer_get_write_areas (&priv->buffer, areas);
+    if (areas[0].len < sizeof (InvokeItem)) {
+      g_warning ("queue full");
+      return SPA_RESULT_ERROR;
+    }
+    item = SPA_MEMBER (priv->buffer_data, areas[0].offset, InvokeItem);
+    item->seq = seq;
+    item->func = func;
+    item->user_data = user_data;
+    item->size = size;
+
+    if (areas[0].len > sizeof (InvokeItem) + size) {
+      item->data = SPA_MEMBER (item, sizeof (InvokeItem), void);
+      item->item_size = sizeof (InvokeItem) + size;
+      if (areas[0].len < sizeof (InvokeItem) + item->item_size)
+        item->item_size = areas[0].len;
+    } else {
+      item->data = SPA_MEMBER (priv->buffer_data, areas[1].offset, void);
+      item->item_size = areas[0].len + 1 + size;
+    }
+    memcpy (item->data, data, size);
 
-  spa_ringbuffer_write_advance (&priv->buffer, item->item_size);
+    spa_ringbuffer_write_advance (&priv->buffer, item->item_size);
 
-  wakeup_thread (this);
+    wakeup_thread (this);
 
-  return SPA_RESULT_RETURN_ASYNC (seq);
+    res = SPA_RESULT_RETURN_ASYNC (seq);
+  }
+  return res;
 }
 
 static void
diff --git a/pinos/server/data-loop.h b/pinos/server/data-loop.h
index 84e2f36b..f70c0cd3 100644
--- a/pinos/server/data-loop.h
+++ b/pinos/server/data-loop.h
@@ -62,10 +62,6 @@ struct _PinosDataLoopClass {
   GObjectClass parent_class;
 };
 
-typedef void (*PinosCommandFunc) (SpaNodeCommand *command,
-                                  uint32_t        seq,
-                                  void           *user_data);
-
 /* normal GObject stuff */
 GType               pinos_data_loop_get_type         (void);
 
diff --git a/pinos/server/main-loop.c b/pinos/server/main-loop.c
index 987bbfc3..c0abed2b 100644
--- a/pinos/server/main-loop.c
+++ b/pinos/server/main-loop.c
@@ -167,7 +167,7 @@ main_loop_dispatch (SpaPollNotifyData *data)
 
   while (spa_ringbuffer_get_read_offset (&priv->buffer, &offset) > 0) {
     item = SPA_MEMBER (priv->buffer_data, offset, InvokeItem);
-    item->func (p, item->seq, item->size, item->data, item->user_data);
+    item->func (p, true, item->seq, item->size, item->data, item->user_data);
     spa_ringbuffer_read_advance (&priv->buffer, item->item_size);
   }
 
@@ -184,38 +184,45 @@ do_invoke (SpaPoll           *poll,
 {
   PinosMainLoop *this = SPA_CONTAINER_OF (poll, PinosMainLoop, poll);
   PinosMainLoopPrivate *priv = this->priv;
+  gboolean in_thread = FALSE;
   SpaRingbufferArea areas[2];
   InvokeItem *item;
   uint64_t u = 1;
+  SpaResult res;
 
-  spa_ringbuffer_get_write_areas (&priv->buffer, areas);
-  if (areas[0].len < sizeof (InvokeItem)) {
-    g_warning ("queue full");
-    return SPA_RESULT_ERROR;
-  }
-  item = SPA_MEMBER (priv->buffer_data, areas[0].offset, InvokeItem);
-  item->seq = seq;
-  item->func = func;
-  item->user_data = user_data;
-  item->size = size;
-
-  if (areas[0].len > sizeof (InvokeItem) + size) {
-    item->data = SPA_MEMBER (item, sizeof (InvokeItem), void);
-    item->item_size = sizeof (InvokeItem) + size;
-    if (areas[0].len < sizeof (InvokeItem) + item->item_size)
-      item->item_size = areas[0].len;
+  if (in_thread) {
+    res = func (poll, false, seq, size, data, user_data);
   } else {
-    item->data = SPA_MEMBER (priv->buffer_data, areas[1].offset, void);
-    item->item_size = areas[0].len + 1 + size;
-  }
-  memcpy (item->data, data, size);
+    spa_ringbuffer_get_write_areas (&priv->buffer, areas);
+    if (areas[0].len < sizeof (InvokeItem)) {
+      g_warning ("queue full");
+      return SPA_RESULT_ERROR;
+    }
+    item = SPA_MEMBER (priv->buffer_data, areas[0].offset, InvokeItem);
+    item->seq = seq;
+    item->func = func;
+    item->user_data = user_data;
+    item->size = size;
+
+    if (areas[0].len > sizeof (InvokeItem) + size) {
+      item->data = SPA_MEMBER (item, sizeof (InvokeItem), void);
+      item->item_size = sizeof (InvokeItem) + size;
+      if (areas[0].len < sizeof (InvokeItem) + item->item_size)
+        item->item_size = areas[0].len;
+    } else {
+      item->data = SPA_MEMBER (priv->buffer_data, areas[1].offset, void);
+      item->item_size = areas[0].len + 1 + size;
+    }
+    memcpy (item->data, data, size);
 
-  spa_ringbuffer_write_advance (&priv->buffer, item->item_size);
+    spa_ringbuffer_write_advance (&priv->buffer, item->item_size);
 
-  if (write (priv->fds[0].fd, &u, sizeof(uint64_t)) != sizeof(uint64_t))
-    g_warning ("data-loop %p: failed to write fd", strerror (errno));
+    if (write (priv->fds[0].fd, &u, sizeof(uint64_t)) != sizeof(uint64_t))
+      g_warning ("data-loop %p: failed to write fd", strerror (errno));
 
-  return SPA_RESULT_RETURN_ASYNC (seq);
+    res = SPA_RESULT_RETURN_ASYNC (seq);
+  }
+  return res;
 }
 
 static void
diff --git a/pinos/server/main-loop.h b/pinos/server/main-loop.h
index 6a2f71aa..65d6b624 100644
--- a/pinos/server/main-loop.h
+++ b/pinos/server/main-loop.h
@@ -62,9 +62,6 @@ struct _PinosMainLoopClass {
   GObjectClass parent_class;
 };
 
-typedef void (*PinosEventFunc) (SpaNodeEvent *event,
-                                void         *user_data);
-
 typedef void (*PinosDeferFunc) (gpointer       obj,
                                 gpointer       data,
                                 SpaResult      res,
diff --git a/pinos/server/node.c b/pinos/server/node.c
index a2c0dbaa..a51e0f38 100644
--- a/pinos/server/node.c
+++ b/pinos/server/node.c
@@ -240,8 +240,7 @@ pause_node (PinosNode *this)
   g_debug ("node %p: pause node", this);
 
   cmd.type = SPA_NODE_COMMAND_PAUSE;
-  cmd.data = NULL;
-  cmd.size = 0;
+  cmd.size = sizeof (cmd);
   if ((res = spa_node_send_command (this->node, &cmd)) < 0)
     g_debug ("got error %d", res);
 
@@ -257,8 +256,7 @@ start_node (PinosNode *this)
   g_debug ("node %p: start node", this);
 
   cmd.type = SPA_NODE_COMMAND_START;
-  cmd.data = NULL;
-  cmd.size = 0;
+  cmd.size = sizeof (cmd);
   if ((res = spa_node_send_command (this->node, &cmd)) < 0)
     g_debug ("got error %d", res);
 
@@ -300,14 +298,11 @@ suspend_node (PinosNode *this)
 static void
 send_clock_update (PinosNode *this)
 {
-  SpaNodeCommand cmd;
   SpaNodeCommandClockUpdate cu;
   SpaResult res;
 
-  cmd.type = SPA_NODE_COMMAND_CLOCK_UPDATE;
-  cmd.data = &cu;
-  cmd.size = sizeof (cu);
-
+  cu.command.type = SPA_NODE_COMMAND_CLOCK_UPDATE;
+  cu.command.size = sizeof (cu);
   cu.flags = 0;
   cu.change_mask = SPA_NODE_COMMAND_CLOCK_UPDATE_TIME |
                    SPA_NODE_COMMAND_CLOCK_UPDATE_SCALE |
@@ -324,7 +319,7 @@ send_clock_update (PinosNode *this)
   cu.scale = (1 << 16) | 1;
   cu.state = SPA_CLOCK_STATE_RUNNING;
 
-  if ((res = spa_node_send_command (this->node, &cmd)) < 0)
+  if ((res = spa_node_send_command (this->node, &cu.command)) < 0)
     g_debug ("got error %d", res);
 }
 
@@ -374,7 +369,7 @@ on_node_event (SpaNode *node, SpaNodeEvent *event, void *user_data)
 
     case SPA_NODE_EVENT_TYPE_ASYNC_COMPLETE:
     {
-      SpaNodeEventAsyncComplete *ac = event->data;
+      SpaNodeEventAsyncComplete *ac = (SpaNodeEventAsyncComplete *) event;
 
       g_debug ("node %p: async complete event %d %d", this, ac->seq, ac->res);
       pinos_main_loop_defer_complete (priv->main_loop, this, ac->seq, ac->res);
@@ -384,7 +379,7 @@ on_node_event (SpaNode *node, SpaNodeEvent *event, void *user_data)
 
     case SPA_NODE_EVENT_TYPE_NEED_INPUT:
     {
-      SpaNodeEventNeedInput *ni = event->data;
+      SpaNodeEventNeedInput *ni = (SpaNodeEventNeedInput *) event;
       PinosPort *p;
       guint i;
 
@@ -401,7 +396,7 @@ on_node_event (SpaNode *node, SpaNodeEvent *event, void *user_data)
     }
     case SPA_NODE_EVENT_TYPE_HAVE_OUTPUT:
     {
-      SpaNodeEventHaveOutput *ho = event->data;
+      SpaNodeEventHaveOutput *ho = (SpaNodeEventHaveOutput *) event;
       SpaPortOutputInfo oinfo[1] = { 0, };
       SpaResult res;
       gboolean pushed = FALSE;
@@ -440,7 +435,7 @@ on_node_event (SpaNode *node, SpaNodeEvent *event, void *user_data)
     case SPA_NODE_EVENT_TYPE_REUSE_BUFFER:
     {
       SpaResult res;
-      SpaNodeEventReuseBuffer *rb = event->data;
+      SpaNodeEventReuseBuffer *rb = (SpaNodeEventReuseBuffer *) event;
       PinosPort *p;
       guint i;
 
diff --git a/spa/include/spa/monitor.h b/spa/include/spa/monitor.h
index bac7aecd..6c04c774 100644
--- a/spa/include/spa/monitor.h
+++ b/spa/include/spa/monitor.h
@@ -33,6 +33,25 @@ typedef struct _SpaMonitor SpaMonitor;
 #include <spa/dict.h>
 #include <spa/plugin.h>
 
+/**
+ * SpaMonitorEventType:
+ * @SPA_MONITOR_EVENT_TYPE_INVALID: invalid event
+ * @SPA_MONITOR_EVENT_TYPE_ADDED: an item was added, data points to #SpaMonitorItem
+ * @SPA_MONITOR_EVENT_TYPE_REMOVED: an item was removed, data points to #SpaMonitorItem
+ * @SPA_MONITOR_EVENT_TYPE_CHANGED: an item was changed, data points to #SpaMonitorItem
+ */
+typedef enum {
+  SPA_MONITOR_EVENT_TYPE_INVALID = 0,
+  SPA_MONITOR_EVENT_TYPE_ADDED,
+  SPA_MONITOR_EVENT_TYPE_REMOVED,
+  SPA_MONITOR_EVENT_TYPE_CHANGED,
+} SpaMonitorEventType;
+
+typedef struct {
+  SpaMonitorEventType  type;
+  size_t               size;
+} SpaMonitorEvent;
+
 typedef enum {
   SPA_MONITOR_ITEM_FLAG_NONE    = 0,
 } SpaMonitorItemFlags;
@@ -50,6 +69,7 @@ typedef enum {
 } SpaMonitorItemState;
 
 typedef struct {
+  SpaMonitorEvent          event;
   const char              *id;
   SpaMonitorItemFlags      flags;
   SpaMonitorItemState      state;
@@ -60,26 +80,6 @@ typedef struct {
 } SpaMonitorItem;
 
 /**
- * SpaMonitorEventType:
- * @SPA_MONITOR_EVENT_TYPE_INVALID: invalid event
- * @SPA_MONITOR_EVENT_TYPE_ADDED: an item was added, data points to #SpaMonitorItem
- * @SPA_MONITOR_EVENT_TYPE_REMOVED: an item was removed, data points to #SpaMonitorItem
- * @SPA_MONITOR_EVENT_TYPE_CHANGED: an item was changed, data points to #SpaMonitorItem
- */
-typedef enum {
-  SPA_MONITOR_EVENT_TYPE_INVALID = 0,
-  SPA_MONITOR_EVENT_TYPE_ADDED,
-  SPA_MONITOR_EVENT_TYPE_REMOVED,
-  SPA_MONITOR_EVENT_TYPE_CHANGED,
-} SpaMonitorEventType;
-
-typedef struct {
-  SpaMonitorEventType  type;
-  void                *data;
-  size_t               size;
-} SpaMonitorEvent;
-
-/**
  * SpaMonitorCallback:
  * @node: a #SpaMonitor emiting the event
  * @event: the event that was emited
diff --git a/spa/include/spa/node-command.h b/spa/include/spa/node-command.h
index c9e728e6..77d243de 100644
--- a/spa/include/spa/node-command.h
+++ b/spa/include/spa/node-command.h
@@ -51,7 +51,6 @@ typedef enum {
 
 struct _SpaNodeCommand {
   SpaNodeCommandType  type;
-  void               *data;
   size_t              size;
 };
 
@@ -68,20 +67,21 @@ struct _SpaNodeCommand {
  * @state: the new clock state, when @change_mask = 1<<2
  */
 typedef struct {
+  SpaNodeCommand command;
 #define SPA_NODE_COMMAND_CLOCK_UPDATE_TIME        (1 << 0)
 #define SPA_NODE_COMMAND_CLOCK_UPDATE_SCALE       (1 << 1)
 #define SPA_NODE_COMMAND_CLOCK_UPDATE_STATE       (1 << 2)
 #define SPA_NODE_COMMAND_CLOCK_UPDATE_LATENCY     (1 << 3)
-  uint32_t      change_mask;
-  int32_t       rate;
-  int64_t       ticks;
-  int64_t       monotonic_time;
-  int64_t       offset;
-  int32_t       scale;
-  SpaClockState state;
+  uint32_t       change_mask;
+  int32_t        rate;
+  int64_t        ticks;
+  int64_t        monotonic_time;
+  int64_t        offset;
+  int32_t        scale;
+  SpaClockState  state;
 #define SPA_NODE_COMMAND_CLOCK_UPDATE_FLAG_LIVE   (1 << 0)
-  uint32_t      flags;
-  int64_t       latency;
+  uint32_t       flags;
+  int64_t        latency;
 } SpaNodeCommandClockUpdate;
 
 #ifdef __cplusplus
diff --git a/spa/include/spa/node-event.h b/spa/include/spa/node-event.h
index 9a4bf7d1..090a00d4 100644
--- a/spa/include/spa/node-event.h
+++ b/spa/include/spa/node-event.h
@@ -68,29 +68,33 @@ typedef enum {
 
 struct _SpaNodeEvent {
   SpaNodeEventType  type;
-  void             *data;
   size_t            size;
 };
 
 typedef struct {
+  SpaNodeEvent event;
   uint32_t     seq;
   SpaResult    res;
 } SpaNodeEventAsyncComplete;
 
 typedef struct {
+  SpaNodeEvent event;
   uint32_t     port_id;
 } SpaNodeEventHaveOutput;
 
 typedef struct {
+  SpaNodeEvent event;
   uint32_t     port_id;
 } SpaNodeEventNeedInput;
 
 typedef struct {
+  SpaNodeEvent event;
   uint32_t port_id;
   uint32_t buffer_id;
 } SpaNodeEventReuseBuffer;
 
 typedef struct {
+  SpaNodeEvent event;
 #define SPA_NODE_EVENT_REQUEST_CLOCK_UPDATE_TIME        (1 << 0)
 #define SPA_NODE_EVENT_REQUEST_CLOCK_UPDATE_SCALE       (1 << 1)
 #define SPA_NODE_EVENT_REQUEST_CLOCK_UPDATE_STATE       (1 << 2)
diff --git a/spa/include/spa/poll.h b/spa/include/spa/poll.h
index df65152b..b1831606 100644
--- a/spa/include/spa/poll.h
+++ b/spa/include/spa/poll.h
@@ -88,6 +88,7 @@ typedef struct {
 
 
 typedef SpaResult (*SpaPollInvokeFunc)  (SpaPoll        *poll,
+                                         bool            async,
                                          uint32_t        seq,
                                          size_t          size,
                                          void           *data,
@@ -131,7 +132,6 @@ struct _SpaPoll {
   SpaResult   (*remove_item)         (SpaPoll         *poll,
                                       SpaPollItem     *item);
 
-
   SpaResult   (*invoke)              (SpaPoll            *poll,
                                       SpaPollInvokeFunc   func,
                                       uint32_t            seq,
diff --git a/spa/plugins/alsa/alsa-monitor.c b/spa/plugins/alsa/alsa-monitor.c
index 447822c3..ab961b07 100644
--- a/spa/plugins/alsa/alsa-monitor.c
+++ b/spa/plugins/alsa/alsa-monitor.c
@@ -216,7 +216,7 @@ alsa_on_fd_events (SpaPollNotifyData *data)
   SpaALSAMonitor *this = data->user_data;
   struct udev_device *dev;
   const char *str;
-  SpaMonitorEvent event;
+  SpaMonitorItem *item;
 
   dev = udev_monitor_receive_device (this->umonitor);
   if (fill_item (&this->uitem, dev) < 0)
@@ -225,16 +225,17 @@ alsa_on_fd_events (SpaPollNotifyData *data)
   if ((str = udev_device_get_action (dev)) == NULL)
     str = "change";
 
+  item = &this->uitem.item;
+
   if (strcmp (str, "add") == 0) {
-    event.type = SPA_MONITOR_EVENT_TYPE_ADDED;
+    item->event.type = SPA_MONITOR_EVENT_TYPE_ADDED;
   } else if (strcmp (str, "change") == 0) {
-    event.type = SPA_MONITOR_EVENT_TYPE_CHANGED;
+    item->event.type = SPA_MONITOR_EVENT_TYPE_CHANGED;
   } else if (strcmp (str, "remove") == 0) {
-    event.type = SPA_MONITOR_EVENT_TYPE_REMOVED;
+    item->event.type = SPA_MONITOR_EVENT_TYPE_REMOVED;
   }
-  event.data = &this->uitem.item;
-  event.size = sizeof (this->uitem);
-  this->event_cb (&this->monitor, &event, this->user_data);
+  item->event.size = sizeof (this->uitem);
+  this->event_cb (&this->monitor, &item->event, this->user_data);
 
   return 0;
 }
diff --git a/spa/plugins/alsa/alsa-utils.c b/spa/plugins/alsa/alsa-utils.c
index 08234a05..258e6d01 100644
--- a/spa/plugins/alsa/alsa-utils.c
+++ b/spa/plugins/alsa/alsa-utils.c
@@ -241,14 +241,12 @@ xrun_recovery (SpaALSAState *state, snd_pcm_t *hndl, int err)
 static void
 pull_input (SpaALSAState *state, void *data, snd_pcm_uframes_t frames)
 {
-  SpaNodeEvent event;
   SpaNodeEventNeedInput ni;
 
-  event.type = SPA_NODE_EVENT_TYPE_NEED_INPUT;
-  event.size = sizeof (ni);
-  event.data = &ni;
+  ni.event.type = SPA_NODE_EVENT_TYPE_NEED_INPUT;
+  ni.event.size = sizeof (ni);
   ni.port_id = 0;
-  state->event_cb (&state->node, &event, state->user_data);
+  state->event_cb (&state->node, &ni.event, state->user_data);
 }
 
 static int
@@ -370,7 +368,6 @@ mmap_read (SpaALSAState *state)
 
 
   if (b) {
-    SpaNodeEvent event;
     SpaNodeEventHaveOutput ho;
     SpaData *d;
 
@@ -380,11 +377,10 @@ mmap_read (SpaALSAState *state)
     b->next = NULL;
     SPA_QUEUE_PUSH_TAIL (&state->ready, SpaALSABuffer, next, b);
 
-    event.type = SPA_NODE_EVENT_TYPE_HAVE_OUTPUT;
-    event.size = sizeof (ho);
-    event.data = &ho;
+    ho.event.type = SPA_NODE_EVENT_TYPE_HAVE_OUTPUT;
+    ho.event.size = sizeof (ho);
     ho.port_id = 0;
-    state->event_cb (&state->node, &event, state->user_data);
+    state->event_cb (&state->node, &ho.event, state->user_data);
   }
   return 0;
 }
diff --git a/spa/plugins/audiomixer/audiomixer.c b/spa/plugins/audiomixer/audiomixer.c
index 814171b6..2d285a61 100644
--- a/spa/plugins/audiomixer/audiomixer.c
+++ b/spa/plugins/audiomixer/audiomixer.c
@@ -566,14 +566,12 @@ spa_audiomixer_node_port_push_input (SpaNode          *node,
 static void
 pull_port (SpaAudioMixer *this, uint32_t port_id, SpaPortOutputInfo *info, size_t pull_size)
 {
-  SpaNodeEvent event;
   SpaNodeEventNeedInput ni;
 
-  event.type = SPA_NODE_EVENT_TYPE_NEED_INPUT;
-  event.size = sizeof (ni);
-  event.data = &ni;
+  ni.event.type = SPA_NODE_EVENT_TYPE_NEED_INPUT;
+  ni.event.size = sizeof (ni);
   ni.port_id = port_id;
-  this->event_cb (&this->node, &event, this->user_data);
+  this->event_cb (&this->node, &ni.event, this->user_data);
 }
 
 static void
diff --git a/spa/plugins/audiotestsrc/audiotestsrc.c b/spa/plugins/audiotestsrc/audiotestsrc.c
index 1d9089bc..17705523 100644
--- a/spa/plugins/audiotestsrc/audiotestsrc.c
+++ b/spa/plugins/audiotestsrc/audiotestsrc.c
@@ -229,15 +229,13 @@ spa_audiotestsrc_node_set_props (SpaNode         *node,
 static SpaResult
 send_have_output (SpaAudioTestSrc *this)
 {
-  SpaNodeEvent event;
   SpaNodeEventHaveOutput ho;
 
   if (this->event_cb) {
-    event.type = SPA_NODE_EVENT_TYPE_HAVE_OUTPUT;
-    event.size = sizeof (ho);
-    event.data = &ho;
+    ho.event.type = SPA_NODE_EVENT_TYPE_HAVE_OUTPUT;
+    ho.event.size = sizeof (ho);
     ho.port_id = 0;
-    this->event_cb (&this->node, &event, this->user_data);
+    this->event_cb (&this->node, &ho.event, this->user_data);
   }
 
   return SPA_RESULT_OK;
diff --git a/spa/plugins/v4l2/v4l2-monitor.c b/spa/plugins/v4l2/v4l2-monitor.c
index 06a7eeb0..eda1043e 100644
--- a/spa/plugins/v4l2/v4l2-monitor.c
+++ b/spa/plugins/v4l2/v4l2-monitor.c
@@ -186,7 +186,8 @@ v4l2_on_fd_events (SpaPollNotifyData *data)
   SpaV4l2Monitor *this = data->user_data;
   struct udev_device *dev;
   const char *action;
-  SpaMonitorEvent event;
+  SpaMonitorItem *item;
+
 
   dev = udev_monitor_receive_device (this->umonitor);
   fill_item (&this->uitem, dev);
@@ -196,16 +197,17 @@ v4l2_on_fd_events (SpaPollNotifyData *data)
   if ((action = udev_device_get_action (dev)) == NULL)
     action = "change";
 
+  item = &this->uitem.item;
+
   if (strcmp (action, "add") == 0) {
-    event.type = SPA_MONITOR_EVENT_TYPE_ADDED;
+    item->event.type = SPA_MONITOR_EVENT_TYPE_ADDED;
   } else if (strcmp (action, "change") == 0) {
-    event.type = SPA_MONITOR_EVENT_TYPE_CHANGED;
+    item->event.type = SPA_MONITOR_EVENT_TYPE_CHANGED;
   } else if (strcmp (action, "remove") == 0) {
-    event.type = SPA_MONITOR_EVENT_TYPE_REMOVED;
+    item->event.type = SPA_MONITOR_EVENT_TYPE_REMOVED;
   }
-  event.data = &this->uitem.item;
-  event.size = sizeof (this->uitem);
-  this->event_cb (&this->monitor, &event, this->user_data);
+  item->event.size = sizeof (this->uitem);
+  this->event_cb (&this->monitor, &item->event, this->user_data);
 
   return 0;
 }
diff --git a/spa/plugins/v4l2/v4l2-source.c b/spa/plugins/v4l2/v4l2-source.c
index 026c0e60..ccd1b103 100644
--- a/spa/plugins/v4l2/v4l2-source.c
+++ b/spa/plugins/v4l2/v4l2-source.c
@@ -225,25 +225,23 @@ spa_v4l2_source_node_set_props (SpaNode         *node,
 }
 
 static SpaResult
-do_command_complete (SpaPoll        *poll,
-                     uint32_t        seq,
-                     size_t          size,
-                     void           *data,
-                     void           *user_data)
+do_send_event (SpaPoll        *poll,
+               bool            async,
+               uint32_t        seq,
+               size_t          size,
+               void           *data,
+               void           *user_data)
 {
   SpaV4l2Source *this = user_data;
-  SpaNodeEvent event;
 
-  event.type = SPA_NODE_EVENT_TYPE_ASYNC_COMPLETE;
-  event.size = size;
-  event.data = data;
-  this->event_cb (&this->node, &event, this->user_data);
+  this->event_cb (&this->node, data, this->user_data);
 
   return SPA_RESULT_OK;
 }
 
 static SpaResult
 do_start (SpaPoll        *poll,
+          bool            async,
           uint32_t        seq,
           size_t          size,
           void           *data,
@@ -255,19 +253,24 @@ do_start (SpaPoll        *poll,
 
   res = spa_v4l2_start (this);
 
-  ac.seq = seq;
-  ac.res = res;
-  spa_poll_invoke (this->state[0].main_loop,
-                   do_command_complete,
-                   seq,
-                   sizeof (ac),
-                   &ac,
-                   this);
+  if (async) {
+    ac.event.type = SPA_NODE_EVENT_TYPE_ASYNC_COMPLETE;
+    ac.event.size = sizeof (SpaNodeEventAsyncComplete);
+    ac.seq = seq;
+    ac.res = res;
+    spa_poll_invoke (this->state[0].main_loop,
+                     do_send_event,
+                     seq,
+                     sizeof (ac),
+                     &ac,
+                     this);
+  }
   return res;
 }
 
 static SpaResult
 do_pause (SpaPoll        *poll,
+          bool            async,
           uint32_t        seq,
           size_t          size,
           void           *data,
@@ -279,18 +282,21 @@ do_pause (SpaPoll        *poll,
 
   res = spa_v4l2_pause (this);
 
-  ac.seq = seq;
-  ac.res = res;
-  spa_poll_invoke (this->state[0].main_loop,
-                   do_command_complete,
-                   seq,
-                   sizeof (ac),
-                   &ac,
-                   this);
+  if (async) {
+    ac.event.type = SPA_NODE_EVENT_TYPE_ASYNC_COMPLETE;
+    ac.event.size = sizeof (SpaNodeEventAsyncComplete);
+    ac.seq = seq;
+    ac.res = res;
+    spa_poll_invoke (this->state[0].main_loop,
+                     do_send_event,
+                     seq,
+                     sizeof (ac),
+                     &ac,
+                     this);
+  }
   return res;
 }
 
-
 static SpaResult
 spa_v4l2_source_node_send_command (SpaNode        *node,
                                    SpaNodeCommand *command)
diff --git a/spa/plugins/v4l2/v4l2-utils.c b/spa/plugins/v4l2/v4l2-utils.c
index fe7333d6..7ff9f043 100644
--- a/spa/plugins/v4l2/v4l2-utils.c
+++ b/spa/plugins/v4l2/v4l2-utils.c
@@ -895,7 +895,6 @@ static int
 v4l2_on_fd_events (SpaPollNotifyData *data)
 {
   SpaV4l2Source *this = data->user_data;
-  SpaNodeEvent event;
   SpaNodeEventHaveOutput ho;
 
   if (data->fds[0].revents & POLLERR)
@@ -907,11 +906,10 @@ v4l2_on_fd_events (SpaPollNotifyData *data)
   if (mmap_read (this) < 0)
     return 0;
 
-  event.type = SPA_NODE_EVENT_TYPE_HAVE_OUTPUT;
-  event.size = sizeof (ho);
-  event.data = &ho;
+  ho.event.type = SPA_NODE_EVENT_TYPE_HAVE_OUTPUT;
+  ho.event.size = sizeof (ho);
   ho.port_id = 0;
-  this->event_cb (&this->node, &event, this->user_data);
+  this->event_cb (&this->node, &ho.event, this->user_data);
 
   return 0;
 }
diff --git a/spa/plugins/videotestsrc/videotestsrc.c b/spa/plugins/videotestsrc/videotestsrc.c
index dafe1a89..601a0177 100644
--- a/spa/plugins/videotestsrc/videotestsrc.c
+++ b/spa/plugins/videotestsrc/videotestsrc.c
@@ -182,15 +182,13 @@ spa_videotestsrc_node_set_props (SpaNode         *node,
 static SpaResult
 send_have_output (SpaVideoTestSrc *this)
 {
-  SpaNodeEvent event;
   SpaNodeEventHaveOutput ho;
 
   if (this->event_cb) {
-    event.type = SPA_NODE_EVENT_TYPE_HAVE_OUTPUT;
-    event.size = sizeof (ho);
-    event.data = &ho;
+    ho.event.type = SPA_NODE_EVENT_TYPE_HAVE_OUTPUT;
+    ho.event.size = sizeof (ho);
     ho.port_id = 0;
-    this->event_cb (&this->node, &event, this->user_data);
+    this->event_cb (&this->node, &ho.event, this->user_data);
   }
 
   return SPA_RESULT_OK;
diff --git a/spa/plugins/volume/volume.c b/spa/plugins/volume/volume.c
index a84f5fa3..0a193b95 100644
--- a/spa/plugins/volume/volume.c
+++ b/spa/plugins/volume/volume.c
@@ -521,15 +521,13 @@ find_free_buffer (SpaVolume *this, SpaVolumePort *port)
 static void
 release_buffer (SpaVolume *this, SpaBuffer *buffer)
 {
-  SpaNodeEvent event;
   SpaNodeEventReuseBuffer rb;
 
-  event.type = SPA_NODE_EVENT_TYPE_REUSE_BUFFER;
-  event.data = &rb;
-  event.size = sizeof (rb);
+  rb.event.type = SPA_NODE_EVENT_TYPE_REUSE_BUFFER;
+  rb.event.size = sizeof (rb);
   rb.port_id = 0;
   rb.buffer_id = buffer->id;
-  this->event_cb (&this->node, &event, this->user_data);
+  this->event_cb (&this->node, &rb.event, this->user_data);
 }
 
 static SpaResult
diff --git a/spa/tests/test-mixer.c b/spa/tests/test-mixer.c
index 2ac3e41d..6b161cd8 100644
--- a/spa/tests/test-mixer.c
+++ b/spa/tests/test-mixer.c
@@ -112,7 +112,7 @@ on_mix_event (SpaNode *node, SpaNodeEvent *event, void *user_data)
       SpaPortInputInfo iinfo;
       SpaPortOutputInfo oinfo;
       SpaResult res;
-      SpaNodeEventNeedInput *ni = event->data;
+      SpaNodeEventNeedInput *ni = (SpaNodeEventNeedInput *) event;
 
       oinfo.port_id = 0;
       oinfo.flags = SPA_PORT_OUTPUT_FLAG_NONE;
@@ -150,7 +150,7 @@ on_sink_event (SpaNode *node, SpaNodeEvent *event, void *user_data)
       SpaPortInputInfo iinfo;
       SpaPortOutputInfo oinfo;
       SpaResult res;
-      SpaNodeEventNeedInput *ni = event->data;
+      SpaNodeEventNeedInput *ni = (SpaNodeEventNeedInput *)event;
 
       oinfo.port_id = 0;
       oinfo.flags = SPA_PORT_OUTPUT_FLAG_PULL;
diff --git a/spa/tools/spa-monitor.c b/spa/tools/spa-monitor.c
index 1c23cb97..4c04fbcb 100644
--- a/spa/tools/spa-monitor.c
+++ b/spa/tools/spa-monitor.c
@@ -71,21 +71,21 @@ on_monitor_event  (SpaMonitor      *monitor,
   switch (event->type) {
     case SPA_MONITOR_EVENT_TYPE_ADDED:
     {
-      SpaMonitorItem *item = event->data;
+      SpaMonitorItem *item = (SpaMonitorItem *) event;
       fprintf (stderr, "added:\n");
       inspect_item (item);
       break;
     }
     case SPA_MONITOR_EVENT_TYPE_REMOVED:
     {
-      SpaMonitorItem *item = event->data;
+      SpaMonitorItem *item = (SpaMonitorItem *) event;
       fprintf (stderr, "removed:\n");
       inspect_item (item);
       break;
     }
     case SPA_MONITOR_EVENT_TYPE_CHANGED:
     {
-      SpaMonitorItem *item = event->data;
+      SpaMonitorItem *item = (SpaMonitorItem *) event;
       fprintf (stderr, "changed:\n");
       inspect_item (item);
       break;