* events.c: events interface
* This library provides an interface to the send and receive events.
* It is more lightweight than variable based callback.
- * Methode
*****************************************************************************
* Copyright (C) 1998-2005 the VideoLAN team
* $Id$
* Preamble
*****************************************************************************/
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
#include <vlc/vlc.h>
#include <assert.h>
{
vlc_event_type_t event_type;
DECL_ARRAY(struct vlc_event_listener_t *) listeners;
+
+ /* Used in vlc_event_send() to make sure to behave
+ Correctly when vlc_event_detach was called during
+ a callback */
+ vlc_bool_t b_sublistener_removed;
+
} vlc_event_listeners_group_t;
#ifdef DEBUG_EVENT
-static const char * ppsz_event_type_to_name[] =
+static const char * ppsz_event_type_to_name[] =
{
[vlc_InputItemMetaChanged] = "vlc_InputItemMetaChanged",
[vlc_InputItemSubItemAdded] = "vlc_InputItemSubItemAdded",
};
#endif
+static vlc_bool_t
+listeners_are_equal( vlc_event_listener_t * listener1,
+ vlc_event_listener_t * listener2 )
+{
+ return listener1->pf_callback == listener2->pf_callback &&
+ listener1->p_user_data == listener2->p_user_data;
+}
+
+static vlc_bool_t
+group_contains_listener( vlc_event_listeners_group_t * group,
+ vlc_event_listener_t * searched_listener )
+{
+ vlc_event_listener_t * listener;
+ FOREACH_ARRAY( listener, group->listeners )
+ if( listeners_are_equal(searched_listener, listener) )
+ return VLC_TRUE;
+ FOREACH_END()
+ return VLC_FALSE;
+}
+
/*****************************************************************************
- *
+ *
*****************************************************************************/
/**
p_em->p_obj = p_obj;
p_em->p_parent_object = p_parent_obj;
vlc_mutex_init( p_parent_obj, &p_em->object_lock );
+
+ /* We need a recursive lock here, because we need to be able
+ * to call libvlc_event_detach even if vlc_event_send is in
+ * the call frame.
+ * This ensures that after libvlc_event_detach, the callback
+ * will never gets triggered.
+ * */
+ vlc_mutex_init_recursive( p_parent_obj, &p_em->event_sending_lock );
ARRAY_INIT( p_em->listeners_groups );
return VLC_SUCCESS;
}
struct vlc_event_listener_t * listener;
vlc_mutex_destroy( &p_em->object_lock );
+ vlc_mutex_destroy( &p_em->event_sending_lock );
FOREACH_ARRAY( listeners_group, p_em->listeners_groups )
FOREACH_ARRAY( listener, listeners_group->listeners )
listeners_group->event_type = event_type;
ARRAY_INIT( listeners_group->listeners );
-
+
vlc_mutex_lock( &p_em->object_lock );
ARRAY_APPEND( p_em->listeners_groups, listeners_group );
vlc_mutex_unlock( &p_em->object_lock );
void vlc_event_send( vlc_event_manager_t * p_em,
vlc_event_t * p_event )
{
- vlc_event_listeners_group_t * listeners_group;
+ vlc_event_listeners_group_t * listeners_group = NULL;
vlc_event_listener_t * listener;
vlc_event_listener_t * array_of_cached_listeners = NULL;
vlc_event_listener_t * cached_listener;
}
FOREACH_END()
vlc_mutex_unlock( &p_em->object_lock );
-
+
/* Call the function attached */
cached_listener = array_of_cached_listeners;
+
+ if( !listeners_group || !array_of_cached_listeners )
+ {
+ free( array_of_cached_listeners );
+ return;
+ }
+
+ vlc_mutex_lock( &p_em->event_sending_lock ) ;
+
+ /* Track item removed from *this* thread, with a simple flag */
+ listeners_group->b_sublistener_removed = VLC_FALSE;
+
for( i = 0; i < i_cached_listeners; i++ )
{
#ifdef DEBUG_EVENT
cached_listener->p_user_data );
free(cached_listener->psz_debug_name);
#endif
-
+ /* No need to lock on listeners_group, a listener group can't be removed */
+ if( listeners_group->b_sublistener_removed )
+ {
+ /* If a callback was removed, this gets called */
+ vlc_bool_t valid_listener;
+ vlc_mutex_lock( &p_em->object_lock );
+ valid_listener = group_contains_listener( listeners_group, cached_listener );
+ vlc_mutex_unlock( &p_em->object_lock );
+ if( !valid_listener )
+ {
+#ifdef DEBUG_EVENT
+ msg_Dbg( p_em->p_parent_object, "Callback was removed during execution" );
+#endif
+ cached_listener++;
+ continue;
+ }
+ }
cached_listener->pf_callback( p_event, cached_listener->p_user_data );
cached_listener++;
}
- free( array_of_cached_listeners );
+ vlc_mutex_unlock( &p_em->event_sending_lock );
+ free( array_of_cached_listeners );
}
/**
listener = malloc(sizeof(vlc_event_listener_t));
if( !listener )
return VLC_ENOMEM;
-
+
listener->p_user_data = p_user_data;
listener->pf_callback = pf_callback;
#ifdef DEBUG_EVENT
/**
* Remove a callback for an event.
*/
+
int vlc_event_detach( vlc_event_manager_t *p_em,
vlc_event_type_t event_type,
vlc_event_callback_t pf_callback,
struct vlc_event_listener_t * listener;
vlc_mutex_lock( &p_em->object_lock );
+ vlc_mutex_lock( &p_em->event_sending_lock );
FOREACH_ARRAY( listeners_group, p_em->listeners_groups )
if( listeners_group->event_type == event_type )
{
if( listener->pf_callback == pf_callback &&
listener->p_user_data == p_user_data )
{
+ /* Tell vlc_event_send, we did remove an item from that group,
+ in case vlc_event_send is in our caller stack */
+ listeners_group->b_sublistener_removed = VLC_TRUE;
+
/* that's our listener */
ARRAY_REMOVE( listeners_group->listeners,
fe_idx /* This comes from the macro (and that's why
free( listener->psz_debug_name );
#endif
free( listener );
+ vlc_mutex_unlock( &p_em->event_sending_lock );
vlc_mutex_unlock( &p_em->object_lock );
return VLC_SUCCESS;
}
FOREACH_END()
}
FOREACH_END()
+ vlc_mutex_unlock( &p_em->event_sending_lock );
vlc_mutex_unlock( &p_em->object_lock );
msg_Warn( p_em->p_parent_object, "Can't detach to an object event manager event" );
return VLC_EGENERIC;
}
+
projects / vlc / blobdiff