* objects.c: vlc_object_t handling
*****************************************************************************
* Copyright (C) 2004-2008 the VideoLAN team
- * $Id$
*
* Authors: Samuel Hocevar <sam@zoy.org>
*
# include "config.h"
#endif
-#include <vlc/vlc.h>
+#include <vlc_common.h>
#include "../libvlc.h"
#include <vlc_vout.h>
#endif
#include <assert.h>
-/*****************************************************************************
- * Constants
- *****************************************************************************/
-
-const vlc_destructor_t kVLCDestructor = NULL;
-
/*****************************************************************************
* Local prototypes
*****************************************************************************/
static vlc_object_t * FindObject ( vlc_object_t *, int, int );
static vlc_object_t * FindObjectName( vlc_object_t *, const char *, int );
-static void DetachObject ( vlc_object_t * );
static void PrintObject ( vlc_object_t *, const char * );
static void DumpStructure ( vlc_object_t *, int, char * );
-static int FindIndex ( vlc_object_t *, vlc_object_t **, int );
-static void SetAttachment ( vlc_object_t *, bool );
static vlc_list_t * NewList ( int );
static void ListReplace ( vlc_list_t *, vlc_object_t *, int );
static void ListChildren ( vlc_list_t *, vlc_object_t *, int );
static void vlc_object_destroy( vlc_object_t *p_this );
-static void vlc_object_yield_locked( vlc_object_t *p_this );
+static void vlc_object_detach_unlocked (vlc_object_t *p_this);
+
+#ifdef LIBVLC_REFCHECK
+static vlc_threadvar_t held_objects;
+typedef struct held_list_t
+{
+ struct held_list_t *next;
+ vlc_object_t *obj;
+} held_list_t;
+static void held_objects_destroy (void *);
+#endif
/*****************************************************************************
* Local structure lock
*****************************************************************************/
-static vlc_mutex_t structure_lock;
+static vlc_mutex_t structure_lock;
-void *vlc_custom_create( vlc_object_t *p_this, size_t i_size,
- int i_type, const char *psz_type )
+void *__vlc_custom_create( vlc_object_t *p_this, size_t i_size,
+ int i_type, const char *psz_type )
{
vlc_object_t *p_new;
vlc_object_internals_t *p_priv;
p_new->b_die = false;
p_new->b_error = false;
p_new->b_dead = false;
- p_priv->b_attached = false;
p_new->b_force = false;
p_new->psz_header = NULL;
p_new->p_libvlc = NULL;
p_libvlc_global->i_counter = 0;
- p_libvlc_global->i_objects = 0;
- p_libvlc_global->pp_objects = NULL;
- p_priv->b_attached = true;
+ p_priv->next = p_priv->prev = p_new;
vlc_mutex_init( &structure_lock );
+#ifdef LIBVLC_REFCHECK
+ /* TODO: use the destruction callback to track ref leaks */
+ vlc_threadvar_create( &held_objects, held_objects_destroy );
+#endif
}
else
{
p_libvlc_global = vlc_global();
if( i_type == VLC_OBJECT_LIBVLC )
- {
p_new->p_libvlc = (libvlc_int_t*)p_new;
- p_priv->b_attached = true;
- }
else
- {
p_new->p_libvlc = p_this->p_libvlc;
- }
}
- vlc_mutex_lock( &structure_lock );
- p_new->i_object_id = p_libvlc_global->i_counter++;
-
- /* Wooohaa! If *this* fails, we're in serious trouble! Anyway it's
- * useless to try and recover anything if pp_objects gets smashed. */
- TAB_APPEND( p_libvlc_global->i_objects, p_libvlc_global->pp_objects,
- p_new );
- vlc_mutex_unlock( &structure_lock );
-
+ vlc_spin_init( &p_priv->ref_spin );
p_priv->i_refcount = 1;
- p_priv->pf_destructor = kVLCDestructor;
+ p_priv->pf_destructor = NULL;
p_priv->b_thread = false;
p_new->p_parent = NULL;
- p_new->pp_children = NULL;
- p_new->i_children = 0;
+ p_priv->pp_children = NULL;
+ p_priv->i_children = 0;
p_new->p_private = NULL;
/* Initialize mutexes and condvars */
- vlc_mutex_init( &p_new->object_lock );
- vlc_cond_init( p_new, &p_new->object_wait );
+ vlc_mutex_init( &p_priv->lock );
+ vlc_cond_init( p_new, &p_priv->wait );
vlc_mutex_init( &p_priv->var_lock );
vlc_spin_init( &p_priv->spin );
p_priv->pipes[0] = p_priv->pipes[1] = -1;
+ p_priv->next = VLC_OBJECT (p_libvlc_global);
+#if !defined (LIBVLC_REFCHECK)
+ /* ... */
+#elif defined (LIBVLC_USE_PTHREAD)
+ p_priv->creator_id = pthread_self ();
+#elif defined (WIN32)
+ p_priv->creator_id = GetCurrentThreadId ();
+#endif
+ vlc_mutex_lock( &structure_lock );
+ p_priv->prev = vlc_internals (p_libvlc_global)->prev;
+ vlc_internals (p_libvlc_global)->prev = p_new;
+ vlc_internals (p_priv->prev)->next = p_new;
+ p_new->i_object_id = p_libvlc_global->i_counter++;
+ vlc_mutex_unlock( &structure_lock );
+
if( i_type == VLC_OBJECT_LIBVLC )
{
var_Create( p_new, "list", VLC_VAR_STRING | VLC_VAR_ISCOMMAND );
switch( i_type )
{
- case VLC_OBJECT_LIBVLC:
- i_size = sizeof(libvlc_int_t);
- psz_type = "libvlc";
- break;
case VLC_OBJECT_INTF:
i_size = sizeof(intf_thread_t);
psz_type = "interface";
break;
- case VLC_OBJECT_DIALOGS:
- i_size = sizeof(intf_thread_t);
- psz_type = "dialogs";
- break;
- case VLC_OBJECT_DEMUX:
- i_size = sizeof(demux_t);
- psz_type = "demux";
- break;
- case VLC_OBJECT_ACCESS:
- i_size = sizeof(access_t);
- psz_type = "access";
- break;
case VLC_OBJECT_DECODER:
i_size = sizeof(decoder_t);
psz_type = "decoder";
i_size = sizeof(encoder_t);
psz_type = "encoder";
break;
- case VLC_OBJECT_FILTER:
- i_size = sizeof(filter_t);
- psz_type = "filter";
- break;
- case VLC_OBJECT_VOUT:
- i_size = sizeof(vout_thread_t);
- psz_type = "video output";
- break;
case VLC_OBJECT_AOUT:
i_size = sizeof(aout_instance_t);
psz_type = "audio output";
break;
- case VLC_OBJECT_SOUT:
- i_size = sizeof(sout_instance_t);
- psz_type = "stream output";
- break;
case VLC_OBJECT_OPENGL:
i_size = sizeof( vout_thread_t );
psz_type = "opengl";
i_size = sizeof( announce_handler_t );
psz_type = "announce";
break;
- case VLC_OBJECT_INTERACTION:
- i_size = sizeof( interaction_t );
- psz_type = "interaction";
- break;
default:
- i_size = i_type > (int)sizeof(vlc_object_t)
- ? i_type : (int)sizeof(vlc_object_t);
+ assert( i_type > 0 ); /* unknown type?! */
+ i_size = i_type;
i_type = VLC_OBJECT_GENERIC;
psz_type = "generic";
break;
{
vlc_object_internals_t *p_priv = vlc_internals( p_this );
- /* Automatically detach the object from its parents */
- if( p_this->p_parent ) vlc_object_detach( p_this );
-
+ /* Objects are always detached beforehand */
+ assert( !p_this->p_parent );
/* Send a kill to the object's thread if applicable */
vlc_object_kill( p_this );
/* If we are running on a thread, wait until it ends */
if( p_priv->b_thread )
+ {
+ msg_Warn (p_this->p_libvlc, /* do NOT use a dead object for logging! */
+ "%s %d destroyed while thread alive (VLC might crash)",
+ p_this->psz_object_type, p_this->i_object_id);
vlc_thread_join( p_this );
+ }
/* Call the custom "subclass" destructor */
if( p_priv->pf_destructor )
p_priv->pf_destructor( p_this );
- /* Sanity checks */
- if( p_this->i_children )
- {
- int i;
-
- fprintf( stderr,
- "ERROR: cannot delete object (%i, %s) with %d children\n",
- p_this->i_object_id, p_this->psz_object_name,
- p_this->i_children );
-
- for( i = 0; i < p_this->i_children; i++ )
- {
- fprintf( stderr,
- "ERROR: Remaining children object "
- "(id:%i, type:%s, name:%s)\n",
- p_this->pp_children[i]->i_object_id,
- p_this->pp_children[i]->psz_object_type,
- p_this->pp_children[i]->psz_object_name );
- }
- fflush(stderr);
-
- /* Dump libvlc object to ease debugging */
- vlc_object_dump( p_this->p_libvlc );
-
- abort();
- }
-
/* Destroy the associated variables, starting from the end so that
* no memmove calls have to be done. */
while( p_priv->i_vars )
if( p_this->p_libvlc == NULL )
{
+#ifndef NDEBUG
libvlc_global_data_t *p_global = (libvlc_global_data_t *)p_this;
-#ifndef NDEBUG
assert( p_global == vlc_global() );
/* Test for leaks */
- if( p_global->i_objects > 0 )
+ if (p_priv->next != p_this)
{
- int i;
- for( i = 0; i < p_global->i_objects; i++ )
+ vlc_object_t *leaked = p_priv->next, *first = leaked;
+ do
{
/* We are leaking this object */
fprintf( stderr,
"ERROR: leaking object (id:%i, type:%s, name:%s)\n",
- p_global->pp_objects[i]->i_object_id,
- p_global->pp_objects[i]->psz_object_type,
- p_global->pp_objects[i]->psz_object_name );
-
+ leaked->i_object_id, leaked->psz_object_type,
+ leaked->psz_object_name );
/* Dump libvlc object to ease debugging */
- vlc_object_dump( p_global->pp_objects[i] );
-
+ vlc_object_dump( leaked );
fflush(stderr);
+ leaked = vlc_internals (leaked)->next;
}
+ while (leaked != first);
- /* Dump libvlc object to ease debugging */
+ /* Dump global object to ease debugging */
vlc_object_dump( p_this );
-
/* Strongly abort, cause we want these to be fixed */
abort();
}
#endif
/* We are the global object ... no need to lock. */
- free( p_global->pp_objects );
- p_global->pp_objects = NULL;
-
vlc_mutex_destroy( &structure_lock );
+#ifdef LIBVLC_REFCHECK
+ held_objects_destroy( vlc_threadvar_get( &held_objects ) );
+ vlc_threadvar_delete( &held_objects );
+#endif
}
FREENULL( p_this->psz_object_name );
#if defined(WIN32) || defined(UNDER_CE)
/* if object has an associated thread, close it now */
- if( p_priv->thread_id.hThread )
- CloseHandle(p_priv->thread_id.hThread);
+ if( p_priv->thread_id )
+ CloseHandle(p_priv->thread_id);
#endif
- vlc_mutex_destroy( &p_this->object_lock );
- vlc_cond_destroy( &p_this->object_wait );
+ vlc_spin_destroy( &p_priv->ref_spin );
+ vlc_mutex_destroy( &p_priv->lock );
+ vlc_cond_destroy( &p_priv->wait );
vlc_spin_destroy( &p_priv->spin );
if( p_priv->pipes[1] != -1 )
close( p_priv->pipes[1] );
void __vlc_object_lock( vlc_object_t *obj )
{
- vlc_mutex_lock( &obj->object_lock );
+ vlc_mutex_lock( &(vlc_internals(obj)->lock) );
}
void __vlc_object_unlock( vlc_object_t *obj )
{
- vlc_assert_locked( &obj->object_lock );
- vlc_mutex_unlock( &obj->object_lock );
+ vlc_assert_locked( &(vlc_internals(obj)->lock) );
+ vlc_mutex_unlock( &(vlc_internals(obj)->lock) );
}
#ifdef WIN32
/**
* Waits for the object to be signaled (using vlc_object_signal()).
- * If the object already has a signal pending, this function will return
- * immediately. It is asserted that the caller holds the object lock.
+ * It is assumed that the caller has locked the object. This function will
+ * unlock the object, and lock it again before returning.
+ * If the object was signaled before the caller locked the object, it is
+ * undefined whether the signal will be lost or will wake the process.
*
* @return true if the object is dying and should terminate.
*/
-bool __vlc_object_wait( vlc_object_t *obj )
+void __vlc_object_wait( vlc_object_t *obj )
{
- vlc_assert_locked( &obj->object_lock );
- vlc_cond_wait( &obj->object_wait, &obj->object_lock );
- return obj->b_die;
+ vlc_object_internals_t *priv = vlc_internals( obj );
+ vlc_assert_locked( &priv->lock);
+ vlc_cond_wait( &priv->wait, &priv->lock );
}
/**
* Waits for the object to be signaled (using vlc_object_signal()), or for
- * a timer to expire.
- * If the object already has a signal pending, this function will return
- * immediately. It is asserted that the caller holds the object lock.
+ * a timer to expire. It is asserted that the caller holds the object lock.
*
- * @return negative if the object is dying and should terminate,
- * positive if the the object has been signaled but is not dying,
- * 0 if timeout has been reached.
+ * @return 0 if the object was signaled before the timer expiration, or
+ * ETIMEDOUT if the timer expired without any signal.
*/
int __vlc_object_timedwait( vlc_object_t *obj, mtime_t deadline )
{
- int v;
-
- vlc_assert_locked( &obj->object_lock );
- v = vlc_cond_timedwait( &obj->object_wait, &obj->object_lock, deadline );
- if( v == 0 ) /* signaled */
- return obj->b_die ? -1 : 1;
- return 0;
-}
-
-
-/**
- * Checks whether an object has been "killed".
- * The object lock must be held.
- *
- * Typical code for an object thread could be:
- *
- vlc_object_lock (self);
- ...initialization...
- while (vlc_object_alive (self))
- {
- ...preprocessing...
-
- if (vlc_object_wait (self))
- continue;
-
- ...postprocessing...
- }
- ...deinitialization...
- vlc_object_unlock (self);
- *
- *
- * @return true iff the object has not been killed yet
- */
-bool __vlc_object_alive( vlc_object_t *obj )
-{
- vlc_assert_locked( &obj->object_lock );
- return !obj->b_die;
+ vlc_object_internals_t *priv = vlc_internals( obj );
+ vlc_assert_locked( &priv->lock);
+ return vlc_cond_timedwait( &priv->wait, &priv->lock, deadline );
}
/**
* Signals an object for which the lock is held.
+ * At least one thread currently sleeping in vlc_object_wait() or
+ * vlc_object_timedwait() will wake up, assuming that there is at least one
+ * such thread in the first place. Otherwise, it is undefined whether the
+ * signal will be lost or will wake up one or more thread later.
*/
void __vlc_object_signal_unlocked( vlc_object_t *obj )
{
- vlc_assert_locked (&obj->object_lock);
- vlc_cond_signal( &obj->object_wait );
+ vlc_assert_locked (&(vlc_internals(obj)->lock));
+ vlc_cond_signal( &(vlc_internals(obj)->wait) );
}
*/
void __vlc_object_kill( vlc_object_t *p_this )
{
- vlc_object_internals_t *internals = vlc_internals( p_this );
+ vlc_object_internals_t *priv = vlc_internals( p_this );
int fd;
- vlc_mutex_lock( &p_this->object_lock );
+ vlc_object_lock( p_this );
p_this->b_die = true;
- vlc_spin_lock (&internals->spin);
- fd = internals->pipes[1];
- internals->pipes[1] = -1;
- vlc_spin_unlock (&internals->spin);
+ vlc_spin_lock (&priv->spin);
+ fd = priv->pipes[1];
+ priv->pipes[1] = -1;
+ vlc_spin_unlock (&priv->spin);
if( fd != -1 )
{
close (fd);
}
- if( p_this->i_object_type == VLC_OBJECT_LIBVLC )
- for( int i = 0; i < p_this->i_children ; i++ )
- vlc_object_kill( p_this->pp_children[i] );
-
vlc_object_signal_unlocked( p_this );
- vlc_mutex_unlock( &p_this->object_lock );
+ /* This also serves as a memory barrier toward vlc_object_alive(): */
+ vlc_object_unlock( p_this );
}
/**
- * find an object given its ID
+ * Find an object given its ID.
*
- * This function looks for the object whose i_object_id field is i_id. We
- * use a dichotomy so that lookups are in log2(n).
- *****************************************************************************/
+ * This function looks for the object whose i_object_id field is i_id.
+ * This function is slow, and often used to hide bugs. Do not use it.
+ * If you need to retain reference to an object, yield the object pointer with
+ * vlc_object_yield(), use the pointer as your reference, and call
+ * vlc_object_release() when you're done.
+ */
void * vlc_object_get( int i_id )
{
- int i_max, i_middle;
- vlc_object_t **pp_objects;
libvlc_global_data_t *p_libvlc_global = vlc_global();
vlc_object_t *obj = NULL;
+#ifndef NDEBUG
+ vlc_object_t *caller = vlc_threadobj ();
+ if (caller)
+ msg_Dbg (caller, "uses deprecated vlc_object_get(%d)", i_id);
+ else
+ fprintf (stderr, "main thread uses deprecated vlc_object_get(%d)\n",
+ i_id);
+#endif
vlc_mutex_lock( &structure_lock );
- pp_objects = p_libvlc_global->pp_objects;
-
- /* Perform our dichotomy */
- for( i_max = p_libvlc_global->i_objects - 1 ; ; )
+ for( obj = vlc_internals (p_libvlc_global)->next;
+ obj != VLC_OBJECT (p_libvlc_global);
+ obj = vlc_internals (obj)->next )
{
- i_middle = i_max / 2;
-
- if( pp_objects[i_middle]->i_object_id > i_id )
- {
- i_max = i_middle;
- }
- else if( pp_objects[i_middle]->i_object_id < i_id )
+ if( obj->i_object_id == i_id )
{
- if( i_middle )
- {
- pp_objects += i_middle;
- i_max -= i_middle;
- }
- else
- {
- /* This happens when there are only two remaining objects */
- if( pp_objects[i_middle+1]->i_object_id == i_id )
- {
- vlc_object_yield_locked( pp_objects[i_middle+1] );
- obj = pp_objects[i_middle+1];
- }
- break;
- }
- }
- else
- {
- vlc_object_yield_locked( pp_objects[i_middle] );
- vlc_mutex_unlock( &structure_lock );
- return pp_objects[i_middle];
+ vlc_object_yield( obj );
+ goto out;
}
}
-
+ obj = NULL;
+#ifndef NDEBUG
+ if (caller)
+ msg_Warn (caller, "wants non-existing object %d", i_id);
+ else
+ fprintf (stderr, "main thread wants non-existing object %d\n", i_id);
+#endif
+out:
vlc_mutex_unlock( &structure_lock );
return obj;
}
{
vlc_object_t *p_found;
- vlc_mutex_lock( &structure_lock );
-
/* If we are of the requested type ourselves, don't look further */
- if( !(i_mode & FIND_STRICT) && p_this->i_object_type == i_type
- && vlc_internals( p_this )->i_refcount > 0 )
+ if( !(i_mode & FIND_STRICT) && p_this->i_object_type == i_type )
{
- vlc_object_yield_locked( p_this );
- vlc_mutex_unlock( &structure_lock );
+ vlc_object_yield( p_this );
return p_this;
}
/* Otherwise, recursively look for the object */
- if( (i_mode & 0x000f) == FIND_ANYWHERE )
+ if ((i_mode & 0x000f) == FIND_ANYWHERE)
{
- vlc_object_t *p_root = p_this;
-
- /* Find the root */
- while( p_root->p_parent != NULL &&
- p_root != VLC_OBJECT( p_this->p_libvlc ) )
- {
- p_root = p_root->p_parent;
- }
-
- p_found = FindObject( p_root, i_type, (i_mode & ~0x000f)|FIND_CHILD );
- if( p_found == NULL && p_root != VLC_OBJECT( p_this->p_libvlc ) )
- {
- p_found = FindObject( VLC_OBJECT( p_this->p_libvlc ),
- i_type, (i_mode & ~0x000f)|FIND_CHILD );
- }
- }
- else
- {
- p_found = FindObject( p_this, i_type, i_mode );
+#ifndef NDEBUG
+ if (i_type == VLC_OBJECT_PLAYLIST)
+ msg_Err (p_this, "using vlc_object_find(VLC_OBJECT_PLAYLIST) "
+ "instead of pl_Yield()");
+#endif
+ return vlc_object_find (p_this->p_libvlc, i_type,
+ (i_mode & ~0x000f)|FIND_CHILD);
}
+ vlc_mutex_lock( &structure_lock );
+ p_found = FindObject( p_this, i_type, i_mode );
vlc_mutex_unlock( &structure_lock );
-
return p_found;
}
{
vlc_object_t *p_found;
- vlc_mutex_lock( &structure_lock );
-
- /* Avoid obvious freed object uses */
- assert( vlc_internals( p_this )->i_refcount > 0 );
-
/* If have the requested name ourselves, don't look further */
if( !(i_mode & FIND_STRICT)
&& p_this->psz_object_name
- && !strcmp( p_this->psz_object_name, psz_name )
- && vlc_internals( p_this )->i_refcount > 0 )
+ && !strcmp( p_this->psz_object_name, psz_name ) )
{
- vlc_object_yield_locked( p_this );
- vlc_mutex_unlock( &structure_lock );
+ vlc_object_yield( p_this );
return p_this;
}
+ vlc_mutex_lock( &structure_lock );
+
/* Otherwise, recursively look for the object */
if( (i_mode & 0x000f) == FIND_ANYWHERE )
{
}
/**
- ****************************************************************************
- * increment an object refcount
- *****************************************************************************/
-
-/* When the structure_lock is locked */
-static void vlc_object_yield_locked( vlc_object_t *p_this )
+ * Increment an object reference counter.
+ */
+void __vlc_object_yield( vlc_object_t *p_this )
{
- vlc_assert_locked (&structure_lock);
+ vlc_object_internals_t *internals = vlc_internals( p_this );
+ vlc_spin_lock( &internals->ref_spin );
/* Avoid obvious freed object uses */
- assert( vlc_internals( p_this )->i_refcount > 0 );
-
+ assert( internals->i_refcount > 0 );
/* Increment the counter */
- vlc_internals( p_this )->i_refcount++;
-}
-
-/* Public function */
-void __vlc_object_yield( vlc_object_t *p_this )
-{
- vlc_mutex_lock( &structure_lock );
- vlc_object_yield_locked( p_this );
- vlc_mutex_unlock( &structure_lock );
+ internals->i_refcount++;
+ vlc_spin_unlock( &internals->ref_spin );
+#ifdef LIBVLC_REFCHECK
+ /* Update the list of referenced objects */
+ /* Using TLS, so no need to lock */
+ /* The following line may leak memory if a thread leaks objects. */
+ held_list_t *newhead = malloc (sizeof (*newhead));
+ held_list_t *oldhead = vlc_threadvar_get (&held_objects);
+ newhead->next = oldhead;
+ newhead->obj = p_this;
+ vlc_threadvar_set (&held_objects, newhead);
+#endif
}
-
/*****************************************************************************
* decrement an object refcount
* And destroy the object if its refcount reach zero.
*****************************************************************************/
void __vlc_object_release( vlc_object_t *p_this )
{
+ vlc_object_internals_t *internals = vlc_internals( p_this );
bool b_should_destroy;
- vlc_mutex_lock( &structure_lock );
+#ifdef LIBVLC_REFCHECK
+ /* Update the list of referenced objects */
+ /* Using TLS, so no need to lock */
+ for (held_list_t *hlcur = vlc_threadvar_get (&held_objects),
+ *hlprev = NULL;
+ hlcur != NULL;
+ hlprev = hlcur, hlcur = hlcur->next)
+ {
+ if (hlcur->obj == p_this)
+ {
+ if (hlprev == NULL)
+ vlc_threadvar_set (&held_objects, hlcur->next);
+ else
+ hlprev->next = hlcur->next;
+ free (hlcur);
+ break;
+ }
+ }
+ /* TODO: what if releasing without references? */
+#endif
+
+ vlc_spin_lock( &internals->ref_spin );
+ assert( internals->i_refcount > 0 );
+
+ if( internals->i_refcount > 1 )
+ {
+ /* Fast path */
+ /* There are still other references to the object */
+ internals->i_refcount--;
+ vlc_spin_unlock( &internals->ref_spin );
+ return;
+ }
+ vlc_spin_unlock( &internals->ref_spin );
- assert( vlc_internals( p_this )->i_refcount > 0 );
- vlc_internals( p_this )->i_refcount--;
- b_should_destroy = (vlc_internals( p_this )->i_refcount == 0);
+ /* Slow path */
+ /* Remember that we cannot hold the spin while waiting on the mutex */
+ vlc_mutex_lock( &structure_lock );
+ /* Take the spin again. Note that another thread may have yielded the
+ * object in the (very short) mean time. */
+ vlc_spin_lock( &internals->ref_spin );
+ b_should_destroy = --internals->i_refcount == 0;
+ vlc_spin_unlock( &internals->ref_spin );
if( b_should_destroy )
{
- /* Make sure this object can't be obtained via vlc_find_object now that
- * it is freed */
- libvlc_global_data_t *p_libvlc_global = vlc_global();
- int i_index;
-
- /* Wooohaa! If *this* fails, we're in serious trouble! Anyway it's
- * useless to try and recover anything if pp_objects gets smashed. */
- i_index = FindIndex( p_this, p_libvlc_global->pp_objects,
- p_libvlc_global->i_objects );
- REMOVE_ELEM( p_libvlc_global->pp_objects,
- p_libvlc_global->i_objects, i_index );
+ /* Remove the object from object list
+ * so that it cannot be encountered by vlc_object_get() */
+ vlc_internals (internals->next)->prev = internals->prev;
+ vlc_internals (internals->prev)->next = internals->next;
+
+ /* Detach from parent to protect against FIND_CHILDREN */
+ vlc_object_detach_unlocked (p_this);
+ /* Detach from children to protect against FIND_PARENT */
+ for (int i = 0; i < internals->i_children; i++)
+ internals->pp_children[i]->p_parent = NULL;
}
vlc_mutex_unlock( &structure_lock );
if( b_should_destroy )
+ {
+ free( internals->pp_children );
+ internals->pp_children = NULL;
+ internals->i_children = 0;
vlc_object_destroy( p_this );
+ }
}
/**
vlc_mutex_lock( &structure_lock );
- /* Avoid obvious freed object uses */
- assert( vlc_internals( p_this )->i_refcount > 0 );
-
/* Attach the parent to its child */
+ assert (!p_this->p_parent);
p_this->p_parent = p_parent;
/* Attach the child to its parent */
- INSERT_ELEM( p_parent->pp_children, p_parent->i_children,
- p_parent->i_children, p_this );
+ vlc_object_internals_t *priv = vlc_internals( p_parent );
+ INSERT_ELEM( priv->pp_children, priv->i_children, priv->i_children,
+ p_this );
+
+ vlc_mutex_unlock( &structure_lock );
+}
+
+
+static void vlc_object_detach_unlocked (vlc_object_t *p_this)
+{
+ vlc_assert_locked (&structure_lock);
+
+ if (p_this->p_parent == NULL)
+ return;
- /* Climb up the tree to see whether we are connected with the root */
- if( vlc_internals( p_parent )->b_attached )
+ vlc_object_internals_t *priv = vlc_internals( p_this->p_parent );
+
+ int i_index, i;
+
+ /* Remove p_this's parent */
+ p_this->p_parent = NULL;
+
+ /* Remove all of p_parent's children which are p_this */
+ for( i_index = priv->i_children ; i_index-- ; )
{
- SetAttachment( p_this, true );
+ if( priv->pp_children[i_index] == p_this )
+ {
+ priv->i_children--;
+ for( i = i_index ; i < priv->i_children ; i++ )
+ priv->pp_children[i] = priv->pp_children[i+1];
+ }
}
- vlc_mutex_unlock( &structure_lock );
+ if( priv->i_children )
+ {
+ priv->pp_children = (vlc_object_t **)realloc( priv->pp_children,
+ priv->i_children * sizeof(vlc_object_t *) );
+ }
+ else
+ {
+ /* Special case - don't realloc() to zero to avoid leaking */
+ free( priv->pp_children );
+ priv->pp_children = NULL;
+ }
}
+
/**
****************************************************************************
* detach object from its parent
if( !p_this ) return;
vlc_mutex_lock( &structure_lock );
-
if( !p_this->p_parent )
- {
msg_Err( p_this, "object is not attached" );
- vlc_mutex_unlock( &structure_lock );
- return;
- }
-
- /* Climb up the tree to see whether we are connected with the root */
- if( vlc_internals( p_this->p_parent )->b_attached )
- {
- SetAttachment( p_this, false );
- }
-
- DetachObject( p_this );
+ else
+ vlc_object_detach_unlocked( p_this );
vlc_mutex_unlock( &structure_lock );
- p_this = NULL;
}
+
/**
****************************************************************************
* find a list typed objects and increment their refcount
vlc_list_t * __vlc_list_find( vlc_object_t *p_this, int i_type, int i_mode )
{
vlc_list_t *p_list;
- vlc_object_t **pp_current, **pp_end;
- int i_count = 0, i_index = 0;
- libvlc_global_data_t *p_libvlc_global = vlc_global();
-
- vlc_mutex_lock( &structure_lock );
+ int i_count = 0;
/* Look for the objects */
switch( i_mode & 0x000f )
{
case FIND_ANYWHERE:
- pp_current = p_libvlc_global->pp_objects;
- pp_end = pp_current + p_libvlc_global->i_objects;
-
- for( ; pp_current < pp_end ; pp_current++ )
- {
- if( vlc_internals(*pp_current)->b_attached
- && (*pp_current)->i_object_type == i_type )
- {
- i_count++;
- }
- }
-
- p_list = NewList( i_count );
- pp_current = p_libvlc_global->pp_objects;
-
- for( ; pp_current < pp_end ; pp_current++ )
- {
- if( vlc_internals(*pp_current)->b_attached
- && (*pp_current)->i_object_type == i_type )
- {
- ListReplace( p_list, *pp_current, i_index );
- if( i_index < i_count ) i_index++;
- }
- }
- break;
+ /* Modules should probably not be object, and the module should perhaps
+ * not be shared across LibVLC instances. In the mean time, this ugly
+ * hack is brought to you by Courmisch. */
+ if (i_type == VLC_OBJECT_MODULE)
+ return vlc_list_find ((vlc_object_t *)vlc_global ()->p_module_bank,
+ i_type, FIND_CHILD);
+ return vlc_list_find (p_this->p_libvlc, i_type, FIND_CHILD);
case FIND_CHILD:
+ vlc_mutex_lock( &structure_lock );
i_count = CountChildren( p_this, i_type );
p_list = NewList( i_count );
/* Check allocation was successful */
if( p_list->i_count != i_count )
{
+ vlc_mutex_unlock( &structure_lock );
msg_Err( p_this, "list allocation failed!" );
p_list->i_count = 0;
break;
p_list->i_count = 0;
ListChildren( p_list, p_this, i_type );
+ vlc_mutex_unlock( &structure_lock );
break;
default:
break;
}
- vlc_mutex_unlock( &structure_lock );
-
return p_list;
}
+/**
+ * Gets the list of children of an objects, and increment their reference
+ * count.
+ * @return a list (possibly empty) or NULL in case of error.
+ */
+vlc_list_t *__vlc_list_children( vlc_object_t *obj )
+{
+ vlc_list_t *l;
+ vlc_object_internals_t *priv = vlc_internals( obj );
+
+ vlc_mutex_lock( &structure_lock );
+ l = NewList( priv->i_children );
+ for (int i = 0; i < l->i_count; i++)
+ {
+ vlc_object_yield( priv->pp_children[i] );
+ l->p_values[i].p_object = priv->pp_children[i];
+ }
+ vlc_mutex_unlock( &structure_lock );
+ return l;
+}
+
/*****************************************************************************
* DumpCommand: print the current vlc structure
*****************************************************************************
static int DumpCommand( vlc_object_t *p_this, char const *psz_cmd,
vlc_value_t oldval, vlc_value_t newval, void *p_data )
{
- libvlc_global_data_t *p_libvlc_global = vlc_global();
-
(void)oldval; (void)p_data;
if( *psz_cmd == 'l' )
{
- vlc_mutex_lock( &structure_lock );
-
- vlc_object_t **pp_current, **pp_end;
-
- pp_current = p_libvlc_global->pp_objects;
- pp_end = pp_current + p_libvlc_global->i_objects;
+ vlc_object_t *root = VLC_OBJECT (vlc_global ()), *cur = root;
- for( ; pp_current < pp_end ; pp_current++ )
+ vlc_mutex_lock( &structure_lock );
+ do
{
- if( vlc_internals(*pp_current)->b_attached )
- {
- PrintObject( *pp_current, "" );
- }
- else
- {
- printf( " o %.8i %s (not attached)\n",
- (*pp_current)->i_object_id,
- (*pp_current)->psz_object_type );
- }
+ PrintObject (cur, "");
+ cur = vlc_internals (cur)->next;
}
-
+ while (cur != root);
vlc_mutex_unlock( &structure_lock );
}
else
if( end != newval.psz_string )
p_object = vlc_object_get( i_id );
else
- {
/* try using the object's name to find it */
- vlc_object_t *p_libvlc = vlc_object_get( 1 );
- if( p_libvlc )
- {
- /* Look in p_libvlc's children tree */
- p_object = vlc_object_find_name( p_libvlc,
- newval.psz_string,
- FIND_CHILD );
- vlc_object_release( p_libvlc );
- }
- if( !p_object )
- {
- /* If it's not in libvlc, look in libvlc_global (== p_this) */
- p_object = vlc_object_find_name( p_this,
- newval.psz_string,
- FIND_CHILD );
- }
- }
+ p_object = vlc_object_find_name( p_this, newval.psz_string,
+ FIND_ANYWHERE );
if( !p_object )
{
/* Following functions are local */
-/*****************************************************************************
- * FindIndex: find the index of an object in an array of objects
- *****************************************************************************
- * This function assumes that p_this can be found in pp_objects. It will not
- * crash if p_this cannot be found, but will return a wrong value. It is your
- * duty to check the return value if you are not certain that the object could
- * be found for sure.
- *****************************************************************************/
-static int FindIndex( vlc_object_t *p_this,
- vlc_object_t **pp_objects, int i_count )
-{
- int i_middle = i_count / 2;
-
- if( i_count == 0 )
- {
- return 0;
- }
-
- if( pp_objects[i_middle] == p_this )
- {
- return i_middle;
- }
-
- if( i_count == 1 )
- {
- return 0;
- }
-
- /* We take advantage of the sorted array */
- if( pp_objects[i_middle]->i_object_id < p_this->i_object_id )
- {
- return i_middle + FindIndex( p_this, pp_objects + i_middle,
- i_count - i_middle );
- }
- else
- {
- return FindIndex( p_this, pp_objects, i_middle );
- }
-}
-
static vlc_object_t * FindObject( vlc_object_t *p_this, int i_type, int i_mode )
{
int i;
p_tmp = p_this->p_parent;
if( p_tmp )
{
- if( p_tmp->i_object_type == i_type
- && vlc_internals( p_tmp )->i_refcount > 0 )
+ if( p_tmp->i_object_type == i_type )
{
- vlc_object_yield_locked( p_tmp );
+ vlc_object_yield( p_tmp );
return p_tmp;
}
else
break;
case FIND_CHILD:
- for( i = p_this->i_children; i--; )
+ for( i = vlc_internals( p_this )->i_children; i--; )
{
- p_tmp = p_this->pp_children[i];
- if( p_tmp->i_object_type == i_type
- && vlc_internals( p_tmp )->i_refcount > 0 )
+ p_tmp = vlc_internals( p_this )->pp_children[i];
+ if( p_tmp->i_object_type == i_type )
{
- vlc_object_yield_locked( p_tmp );
+ vlc_object_yield( p_tmp );
return p_tmp;
}
- else if( p_tmp->i_children )
+ else if( vlc_internals( p_tmp )->i_children )
{
p_tmp = FindObject( p_tmp, i_type, i_mode );
if( p_tmp )
if( p_tmp )
{
if( p_tmp->psz_object_name
- && !strcmp( p_tmp->psz_object_name, psz_name )
- && vlc_internals( p_tmp )->i_refcount > 0 )
+ && !strcmp( p_tmp->psz_object_name, psz_name ) )
{
- vlc_object_yield_locked( p_tmp );
+ vlc_object_yield( p_tmp );
return p_tmp;
}
else
break;
case FIND_CHILD:
- for( i = p_this->i_children; i--; )
+ for( i = vlc_internals( p_this )->i_children; i--; )
{
- p_tmp = p_this->pp_children[i];
+ p_tmp = vlc_internals( p_this )->pp_children[i];
if( p_tmp->psz_object_name
- && !strcmp( p_tmp->psz_object_name, psz_name )
- && vlc_internals( p_tmp )->i_refcount > 0 )
+ && !strcmp( p_tmp->psz_object_name, psz_name ) )
{
- vlc_object_yield_locked( p_tmp );
+ vlc_object_yield( p_tmp );
return p_tmp;
}
- else if( p_tmp->i_children )
+ else if( vlc_internals( p_tmp )->i_children )
{
p_tmp = FindObjectName( p_tmp, psz_name, i_mode );
if( p_tmp )
return NULL;
}
-static void DetachObject( vlc_object_t *p_this )
-{
- vlc_object_t *p_parent = p_this->p_parent;
- int i_index, i;
-
- /* Remove p_this's parent */
- p_this->p_parent = NULL;
-
- /* Remove all of p_parent's children which are p_this */
- for( i_index = p_parent->i_children ; i_index-- ; )
- {
- if( p_parent->pp_children[i_index] == p_this )
- {
- p_parent->i_children--;
- for( i = i_index ; i < p_parent->i_children ; i++ )
- {
- p_parent->pp_children[i] = p_parent->pp_children[i+1];
- }
- }
- }
-
- if( p_parent->i_children )
- {
- p_parent->pp_children = (vlc_object_t **)realloc( p_parent->pp_children,
- p_parent->i_children * sizeof(vlc_object_t *) );
- }
- else
- {
- free( p_parent->pp_children );
- p_parent->pp_children = NULL;
- }
-}
-
-/*****************************************************************************
- * SetAttachment: recursively set the b_attached flag of a subtree.
- *****************************************************************************
- * This function is used by the attach and detach functions to propagate
- * the b_attached flag in a subtree.
- *****************************************************************************/
-static void SetAttachment( vlc_object_t *p_this, bool b_attached )
-{
- int i_index;
-
- for( i_index = p_this->i_children ; i_index-- ; )
- {
- SetAttachment( p_this->pp_children[i_index], b_attached );
- }
-
- vlc_internals( p_this )->b_attached = b_attached;
-}
static void PrintObject( vlc_object_t *p_this, const char *psz_prefix )
{
}
psz_children[0] = '\0';
- switch( p_this->i_children )
+ switch( vlc_internals( p_this )->i_children )
{
case 0:
break;
strcpy( psz_children, ", 1 child" );
break;
default:
- snprintf( psz_children, 19, ", %i children", p_this->i_children );
+ snprintf( psz_children, 19, ", %i children",
+ vlc_internals( p_this )->i_children );
break;
}
psz_thread[0] = '\0';
if( vlc_internals( p_this )->b_thread )
- snprintf( psz_thread, 29, " (thread %u)",
-#if defined(WIN32) || defined(UNDER_CE)
- (unsigned)vlc_internals( p_this )->thread_id.id );
-#else
- (unsigned)vlc_internals( p_this )->thread_id );
-#endif
+ snprintf( psz_thread, 29, " (thread %lu)",
+ (unsigned long)vlc_internals( p_this )->thread_id );
psz_parent[0] = '\0';
if( p_this->p_parent )
return;
}
- for( i = 0 ; i < p_this->i_children ; i++ )
+ for( i = 0 ; i < vlc_internals( p_this )->i_children ; i++ )
{
if( i_level )
{
}
}
- if( i == p_this->i_children - 1 )
+ if( i == vlc_internals( p_this )->i_children - 1 )
{
psz_foo[i_level] = '`';
}
psz_foo[i_level+1] = '-';
psz_foo[i_level+2] = '\0';
- DumpStructure( p_this->pp_children[i], i_level + 2, psz_foo );
+ DumpStructure( vlc_internals( p_this )->pp_children[i], i_level + 2,
+ psz_foo );
}
}
return;
}
- vlc_object_yield_locked( p_object );
+ vlc_object_yield( p_object );
p_list->p_values[i_index].p_object = p_object;
return;
}
- vlc_object_yield_locked( p_object );
+ vlc_object_yield( p_object );
p_list->p_values[p_list->i_count].p_object = p_object;
p_list->i_count++;
vlc_object_t *p_tmp;
int i, i_count = 0;
- for( i = 0; i < p_this->i_children; i++ )
+ for( i = 0; i < vlc_internals( p_this )->i_children; i++ )
{
- p_tmp = p_this->pp_children[i];
+ p_tmp = vlc_internals( p_this )->pp_children[i];
if( p_tmp->i_object_type == i_type )
{
i_count++;
}
-
- if( p_tmp->i_children )
- {
- i_count += CountChildren( p_tmp, i_type );
- }
+ i_count += CountChildren( p_tmp, i_type );
}
return i_count;
vlc_object_t *p_tmp;
int i;
- for( i = 0; i < p_this->i_children; i++ )
+ for( i = 0; i < vlc_internals( p_this )->i_children; i++ )
{
- p_tmp = p_this->pp_children[i];
+ p_tmp = vlc_internals( p_this )->pp_children[i];
if( p_tmp->i_object_type == i_type )
- {
ListReplace( p_list, p_tmp, p_list->i_count++ );
- }
- if( p_tmp->i_children )
- {
- ListChildren( p_list, p_tmp, i_type );
- }
+ ListChildren( p_list, p_tmp, i_type );
}
}
+
+#ifdef LIBVLC_REFCHECK
+# if defined(HAVE_EXECINFO_H) && defined(HAVE_BACKTRACE)
+# include <execinfo.h>
+# endif
+
+void vlc_refcheck (vlc_object_t *obj)
+{
+ static unsigned errors = 0;
+ if (errors > 100)
+ return;
+
+ /* Anyone can use the root object (though it should not exist) */
+ if (obj == VLC_OBJECT (vlc_global ()))
+ return;
+
+ /* Anyone can use its libvlc instance object */
+ if (obj == VLC_OBJECT (obj->p_libvlc))
+ return;
+
+ /* The thread that created the object holds the initial reference */
+ vlc_object_internals_t *priv = vlc_internals (obj);
+#if defined (LIBVLC_USE_PTHREAD)
+ if (pthread_equal (priv->creator_id, pthread_self ()))
+#elif defined WIN32
+ if (priv->creator_id == GetCurrentThreadId ())
+#else
+ if (0)
+#endif
+ return;
+
+ /* A thread can use its own object without references! */
+ vlc_object_t *caller = vlc_threadobj ();
+ if (caller == obj)
+ return;
+#if 0
+ /* The calling thread is younger than the object.
+ * Access could be valid through cross-thread synchronization;
+ * we would need better accounting. */
+ if (caller && (caller->i_object_id > obj->i_object_id))
+ return;
+#endif
+ int refs;
+ vlc_spin_lock (&priv->ref_spin);
+ refs = priv->i_refcount;
+ vlc_spin_unlock (&priv->ref_spin);
+
+ for (held_list_t *hlcur = vlc_threadvar_get (&held_objects);
+ hlcur != NULL; hlcur = hlcur->next)
+ if (hlcur->obj == obj)
+ return;
+
+ fprintf (stderr, "The %s %s thread object is accessing...\n"
+ "the %s %s object without references.\n",
+ caller && caller->psz_object_name
+ ? caller->psz_object_name : "unnamed",
+ caller ? caller->psz_object_type : "main",
+ obj->psz_object_name ? obj->psz_object_name : "unnamed",
+ obj->psz_object_type);
+ fflush (stderr);
+
+#ifdef HAVE_BACKTRACE
+ void *stack[20];
+ int stackdepth = backtrace (stack, sizeof (stack) / sizeof (stack[0]));
+ backtrace_symbols_fd (stack, stackdepth, 2);
+#endif
+
+ if (++errors == 100)
+ fprintf (stderr, "Too many reference errors!\n");
+}
+
+static void held_objects_destroy (void *data)
+{
+ VLC_UNUSED( data );
+ held_list_t *hl = vlc_threadvar_get (&held_objects);
+ vlc_object_t *caller = vlc_threadobj ();
+
+ while (hl != NULL)
+ {
+ held_list_t *buf = hl->next;
+ vlc_object_t *obj = hl->obj;
+
+ fprintf (stderr, "The %s %s thread object leaked a reference to...\n"
+ "the %s %s object.\n",
+ caller && caller->psz_object_name
+ ? caller->psz_object_name : "unnamed",
+ caller ? caller->psz_object_type : "main",
+ obj->psz_object_name ? obj->psz_object_name : "unnamed",
+ obj->psz_object_type);
+ free (hl);
+ hl = buf;
+ }
+}
+#endif