* 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>
static void vlc_object_destroy( 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_threadvar_t thread_object;
void *vlc_custom_create( vlc_object_t *p_this, size_t i_size,
int i_type, const char *psz_type )
p_libvlc_global->i_counter = 0;
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_priv->pipes[0] = p_priv->pipes[1] = -1;
p_priv->next = VLC_OBJECT (p_libvlc_global);
-#if defined (NDEBUG)
+#if !defined (LIBVLC_REFCHECK)
/* ... */
#elif defined (LIBVLC_USE_PTHREAD)
p_priv->creator_id = pthread_self ();
/* We are the global object ... no need to lock. */
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 );
/**
* 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;
}
/**
* 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;
+ return vlc_cond_timedwait( &obj->object_wait, &obj->object_lock, deadline );
}
{
...preprocessing...
- if (vlc_object_wait (self))
- continue;
+ vlc_object_wait (self);
...postprocessing...
}
/**
* 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 )
{
close (fd);
}
- if( p_this->i_object_type == VLC_OBJECT_LIBVLC )
- for( int i = 0; i < internals->i_children ; i++ )
- vlc_object_kill( internals->pp_children[i] );
-
vlc_object_signal_unlocked( p_this );
vlc_mutex_unlock( &p_this->object_lock );
+
+ if (p_this->i_object_type == VLC_OBJECT_LIBVLC)
+ {
+ vlc_list_t *children = vlc_list_children (p_this);
+ for (int i = 0; i < children->i_count; i++)
+ vlc_object_kill (children->p_values[i].p_object);
+ vlc_list_release (children);
+ }
}
{
libvlc_global_data_t *p_libvlc_global = vlc_global();
vlc_object_t *obj = NULL;
+#ifndef NDEBUG
vlc_object_t *caller = vlc_threadobj ();
if (caller)
else
fprintf (stderr, "main thread uses deprecated vlc_object_get(%d)\n",
i_id);
-
+#endif
vlc_mutex_lock( &structure_lock );
for( obj = vlc_internals (p_libvlc_global)->next;
}
}
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;
/* Increment the counter */
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
}
/*****************************************************************************
vlc_object_internals_t *internals = vlc_internals( p_this );
bool b_should_destroy;
+#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 );
}
}
-#ifndef NDEBUG
-# if defined(__GLIBC__) || defined(__APPLE__)
+#ifdef LIBVLC_REFCHECK
+# if defined(HAVE_EXECINFO_H) && defined(HAVE_BACKTRACE)
# include <execinfo.h>
# endif
#endif
return;
- /* A thread can use its own object without reference! */
+ /* 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);
- /* Object has more than one reference.
- * The current thread could be holding a valid reference. */
- if (refs > 1)
- return;
+ 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 in a suspicous manner.\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_type);
fflush (stderr);
-#if defined(__GLIBC__) || defined(__APPLE__)
+#ifdef HAVE_BACKTRACE
void *stack[20];
int stackdepth = backtrace (stack, sizeof (stack) / sizeof (stack[0]));
backtrace_symbols_fd (stack, stackdepth, 2);
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
projects / vlc / blobdiff