* 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
*****************************************************************************/
-#include <vlc/vlc.h>
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
-#include <stdio.h> /* required */
-#include <stdlib.h> /* malloc() */
+#include <vlc_common.h>
#include <assert.h>
* Documentation : Read vlc_events.h
*****************************************************************************/
+//#define DEBUG_EVENT
+
/*****************************************************************************
* Private types.
*****************************************************************************/
{
void * p_user_data;
vlc_event_callback_t pf_callback;
+#ifdef DEBUG_EVENT
+ char * psz_debug_name;
+#endif
} vlc_event_listener_t;
typedef struct vlc_event_listeners_group_t
{
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 */
+ bool b_sublistener_removed;
+
} vlc_event_listeners_group_t;
+#ifdef DEBUG_EVENT
+static const char ppsz_event_type_to_name[][33] =
+{
+ [vlc_InputStateChanged] = "vlc_InputStateChanged",
+ [vlc_InputSelectedStreamChanged] = "vlc_InputSelectedStreamChanged",
+
+ [vlc_InputItemMetaChanged] = "vlc_InputItemMetaChanged",
+ [vlc_InputItemSubItemAdded] = "vlc_InputItemSubItemAdded",
+ [vlc_InputItemDurationChanged] = "vlc_InputItemDurationChanged",
+ [vlc_InputItemPreparsedChanged] = "vlc_InputItemPreparsedChanged",
+ [vlc_InputItemNameChanged] = "vlc_InputItemNameChanged",
+ [vlc_InputItemInfoChanged] = "vlc_InputItemInfoChanged",
+ [vlc_InputItemErrorWhenReadingChanged] = "vlc_InputItemErrorWhenReadingChanged",
+
+ [vlc_ServicesDiscoveryItemAdded] = "vlc_ServicesDiscoveryItemAdded",
+ [vlc_ServicesDiscoveryItemRemoved] = "vlc_ServicesDiscoveryItemRemoved"
+ [vlc_ServicesDiscoveryStarted] = "vlc_ServicesDiscoveryStarted"
+ [vlc_ServicesDiscoveryEnded] = "vlc_ServicesDiscoveryEnded"
+};
+#endif
+
+static bool
+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 bool
+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 true;
+ FOREACH_END()
+ return false;
+}
+
/*****************************************************************************
- *
+ *
*****************************************************************************/
/**
* Initialize event manager object
- * p_this is the object that contains the event manager. But not
+ * p_obj is the object that contains the event manager. But not
* necessarily a vlc_object_t (an input_item_t is not a vlc_object_t
* for instance).
+ * p_parent_obj gives a libvlc instance
*/
-int vlc_event_manager_init( vlc_event_manager_t * p_em, void * p_obj )
+int __vlc_event_manager_init( vlc_event_manager_t * p_em, void * p_obj,
+ vlc_object_t * p_parent_obj )
{
p_em->p_obj = p_obj;
+ p_em->p_parent_object = p_parent_obj;
+ vlc_mutex_init( &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_em->event_sending_lock );
ARRAY_INIT( p_em->listeners_groups );
return VLC_SUCCESS;
}
struct vlc_event_listeners_group_t * listeners_group;
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 )
free( listener );
FOREACH_END()
+ ARRAY_RESET( listeners_group->listeners );
free( listeners_group );
FOREACH_END()
+ ARRAY_RESET( p_em->listeners_groups );
}
/**
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 );
return VLC_SUCCESS;
}
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;
+ int i, i_cached_listeners = 0;
/* Fill event with the sending object now */
p_event->p_obj = p_em->p_obj;
+ vlc_mutex_lock( &p_em->object_lock );
FOREACH_ARRAY( listeners_group, p_em->listeners_groups )
if( listeners_group->event_type == p_event->type )
{
- /* We found the group, now send every one the event */
+ if( listeners_group->listeners.i_size <= 0 )
+ break;
+
+ /* Save the function to call */
+ i_cached_listeners = listeners_group->listeners.i_size;
+ array_of_cached_listeners = malloc(
+ sizeof(vlc_event_listener_t)*i_cached_listeners );
+ if( !array_of_cached_listeners )
+ {
+ vlc_mutex_unlock( &p_em->object_lock );
+ return;
+ }
+
+ cached_listener = array_of_cached_listeners;
FOREACH_ARRAY( listener, listeners_group->listeners )
- listener->pf_callback( p_event, listener->p_user_data );
+ memcpy( cached_listener, listener, sizeof(vlc_event_listener_t));
+#ifdef DEBUG_EVENT
+ cached_listener->psz_debug_name = strdup(cached_listener->psz_debug_name);
+#endif
+ cached_listener++;
FOREACH_END()
+
break;
}
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 = false;
+
+ for( i = 0; i < i_cached_listeners; i++ )
+ {
+#ifdef DEBUG_EVENT
+ msg_Dbg( p_em->p_parent_object,
+ "Calling '%s' with a '%s' event (data %p)",
+ cached_listener->psz_debug_name,
+ ppsz_event_type_to_name[p_event->type],
+ 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 */
+ bool 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++;
+ }
+ vlc_mutex_unlock( &p_em->event_sending_lock );
+
+ free( array_of_cached_listeners );
}
/**
* Add a callback for an event.
*/
-int vlc_event_attach( vlc_event_manager_t * p_event_manager,
- vlc_event_type_t event_type,
- vlc_event_callback_t pf_callback,
- void *p_user_data )
+int __vlc_event_attach( vlc_event_manager_t * p_em,
+ vlc_event_type_t event_type,
+ vlc_event_callback_t pf_callback,
+ void *p_user_data,
+ const char * psz_debug_name )
{
vlc_event_listeners_group_t * listeners_group;
vlc_event_listener_t * listener;
listener = malloc(sizeof(vlc_event_listener_t));
if( !listener )
return VLC_ENOMEM;
-
+
listener->p_user_data = p_user_data;
listener->pf_callback = pf_callback;
-
- FOREACH_ARRAY( listeners_group, p_event_manager->listeners_groups )
+#ifdef DEBUG_EVENT
+ listener->psz_debug_name = strdup( psz_debug_name );
+#else
+ (void)psz_debug_name;
+#endif
+
+ vlc_mutex_lock( &p_em->object_lock );
+ FOREACH_ARRAY( listeners_group, p_em->listeners_groups )
if( listeners_group->event_type == event_type )
{
ARRAY_APPEND( listeners_group->listeners, listener );
+#ifdef DEBUG_EVENT
+ msg_Dbg( p_em->p_parent_object,
+ "Listening to '%s' event with '%s' (data %p)",
+ ppsz_event_type_to_name[event_type],
+ listener->psz_debug_name,
+ listener->p_user_data );
+#endif
+ vlc_mutex_unlock( &p_em->object_lock );
return VLC_SUCCESS;
}
FOREACH_END()
-
+ vlc_mutex_unlock( &p_em->object_lock );
+
+ msg_Err( p_em->p_parent_object, "Can't attach to an object event manager event" );
free(listener);
return VLC_EGENERIC;
}
/**
* Remove a callback for an event.
*/
-int vlc_event_detach( vlc_event_manager_t *p_event_manager,
+
+int vlc_event_detach( vlc_event_manager_t *p_em,
vlc_event_type_t event_type,
vlc_event_callback_t pf_callback,
void *p_user_data )
{
vlc_event_listeners_group_t * listeners_group;
struct vlc_event_listener_t * listener;
- FOREACH_ARRAY( listeners_group, p_event_manager->listeners_groups )
+
+ 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 )
{
FOREACH_ARRAY( listener, listeners_group->listeners )
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 = true;
+
/* that's our listener */
- free( listener );
ARRAY_REMOVE( listeners_group->listeners,
fe_idx /* This comes from the macro (and that's why
I hate macro) */ );
+#ifdef DEBUG_EVENT
+ msg_Dbg( p_em->p_parent_object,
+ "Detaching '%s' from '%s' event (data %p)",
+ listener->psz_debug_name,
+ ppsz_event_type_to_name[event_type],
+ listener->p_user_data );
+
+ 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