* objects.c: vlc_object_t handling
*****************************************************************************
* Copyright (C) 2004-2008 the VideoLAN team
- * $Id$
*
* Authors: Samuel Hocevar <sam@zoy.org>
*
/**
* \file
* This file contains the functions to handle the vlc_object_t type
+ *
+ * Unless otherwise stated, functions in this file are not cancellation point.
+ * All functions in this file are safe w.r.t. deferred cancellation.
*/
# 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);
+static void vlc_object_dump( vlc_object_t *p_this );
/*****************************************************************************
* Local structure lock
*****************************************************************************/
-static vlc_mutex_t structure_lock;
-static vlc_threadvar_t thread_object;
+static vlc_mutex_t structure_lock;
+
+static void close_nocancel (int fd)
+{
+ int canc = vlc_savecancel ();
+ close (fd);
+ vlc_restorecancel (canc);
+}
-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_new->b_force = false;
p_new->psz_header = NULL;
return NULL;
}
- libvlc_global_data_t *p_libvlc_global;
if( p_this == NULL )
{
- /* Only the global root object is created out of the blue */
- p_libvlc_global = (libvlc_global_data_t *)p_new;
- p_new->p_libvlc = NULL;
-
- p_libvlc_global->i_counter = 0;
- p_priv->next = p_priv->prev = p_new;
- vlc_mutex_init( &structure_lock );
- }
- else
- {
- p_libvlc_global = vlc_global();
if( i_type == VLC_OBJECT_LIBVLC )
p_new->p_libvlc = (libvlc_int_t*)p_new;
else
- p_new->p_libvlc = p_this->p_libvlc;
+ {
+ p_new->p_libvlc = NULL;
+ vlc_mutex_init( &structure_lock );
+ }
+
+ p_this = p_priv->next = p_priv->prev = p_new;
}
+ else
+ p_new->p_libvlc = p_this->p_libvlc;
vlc_spin_init( &p_priv->ref_spin );
p_priv->i_refcount = 1;
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_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);
+ p_priv->next = p_this;
vlc_mutex_lock( &structure_lock );
- p_priv->prev = vlc_internals (p_libvlc_global)->prev;
- vlc_internals (p_libvlc_global)->prev = p_new;
+ p_priv->prev = vlc_internals (p_this)->prev;
+ vlc_internals (p_this)->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 )
{
+ int canc = vlc_savecancel ();
var_Create( p_new, "list", VLC_VAR_STRING | VLC_VAR_ISCOMMAND );
var_AddCallback( p_new, "list", DumpCommand, NULL );
var_Create( p_new, "tree", VLC_VAR_STRING | VLC_VAR_ISCOMMAND );
var_AddCallback( p_new, "tree", DumpCommand, NULL );
var_Create( p_new, "vars", VLC_VAR_STRING | VLC_VAR_ISCOMMAND );
var_AddCallback( p_new, "vars", DumpCommand, NULL );
+ vlc_restorecancel (canc);
}
return p_new;
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";
break;
- case VLC_OBJECT_ANNOUNCE:
- 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;
* This function destroys an object that has been previously allocated with
* vlc_object_create. The object's refcount must be zero and it must not be
* attached to other objects in any way.
+ *
+ * This function must be called with cancellation disabled (currently).
*****************************************************************************/
static void vlc_object_destroy( vlc_object_t *p_this )
{
/* 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 )
- vlc_thread_join( p_this );
-
/* Call the custom "subclass" destructor */
if( p_priv->pf_destructor )
p_priv->pf_destructor( p_this );
+ /* Any thread must have been cleaned up at this point. */
+ assert( !p_priv->b_thread );
+
/* Destroy the associated variables, starting from the end so that
* no memmove calls have to be done. */
while( p_priv->i_vars )
free( p_this->psz_header );
if( p_this->p_libvlc == NULL )
- {
- libvlc_global_data_t *p_global = (libvlc_global_data_t *)p_this;
-
-#ifndef NDEBUG
- assert( p_global == vlc_global() );
- /* Test for leaks */
- for( vlc_object_t *leaked = p_priv->next;
- leaked != p_this;
- leaked = vlc_internals (leaked)->next )
- {
- /* We are leaking this object */
- fprintf( stderr,
- "ERROR: leaking object (id:%i, type:%s, name:%s)\n",
- leaked->i_object_id, leaked->psz_object_type,
- leaked->psz_object_name );
- /* Dump libvlc object to ease debugging */
- vlc_object_dump( leaked );
- fflush(stderr);
- }
-
- if( p_priv->next != p_this )
- {
- /* Dump libvlc 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. */
vlc_mutex_destroy( &structure_lock );
- }
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 )
- CloseHandle(p_priv->thread_id);
-#endif
-
vlc_spin_destroy( &p_priv->ref_spin );
- vlc_mutex_destroy( &p_this->object_lock );
- vlc_cond_destroy( &p_this->object_wait );
+ 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.
+ * Suspends until another thread calls vlc_object_signal_unlocked().
+ * The thread may be woken up earlier due to limitations of the underlying
+ * implementation.
*
- * @return true if the object is dying and should terminate.
- */
-bool __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.
+ * In new code, please use vlc_cond_wait() instead.
*
- * @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.
+ * This function is a cancellation point. In case of cancellation, the object
+ * will be in locked state.
*/
-int __vlc_object_timedwait( vlc_object_t *obj, mtime_t deadline )
+void __vlc_object_wait( vlc_object_t *obj )
{
- 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;
+ vlc_object_internals_t *priv = vlc_internals( obj );
+ vlc_assert_locked( &priv->lock);
+ vlc_cond_wait( &priv->wait, &priv->lock );
}
/**
- * Checks whether an object has been "killed".
- * The object lock must be held.
- *
- * Typical code for an object thread could be:
+ * Wakes up one thread waiting on the object. If no thread are (yet) waiting,
+ * nothing happens.
*
- 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;
-}
-
-
-/**
- * Signals an object for which the lock is held.
+ * Please do not use this function in new code as we are trying to untangle
+ * objects and threads. Use vlc_cond_wait() instead.
*/
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_thread_cancel( p_this );
+ 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 )
{
msg_Dbg (p_this, "waitpipe: object killed");
- close (fd);
+ close_nocancel (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 );
+ vlc_cond_broadcast (&priv->wait);
+ /* This also serves as a memory barrier toward vlc_object_alive(): */
+ vlc_object_unlock( p_this );
}
-/**
- * Find an object given its ID.
- *
- * 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 )
-{
- libvlc_global_data_t *p_libvlc_global = vlc_global();
- vlc_object_t *obj = NULL;
-
- vlc_mutex_lock( &structure_lock );
-
- for( obj = vlc_internals (p_libvlc_global)->next;
- obj != VLC_OBJECT (p_libvlc_global);
- obj = vlc_internals (obj)->next )
- {
- if( obj->i_object_id == i_id )
- {
- vlc_object_yield( obj );
- goto out;
- }
- }
- obj = NULL;
-
-out:
- vlc_mutex_unlock( &structure_lock );
- return obj;
-}
-
-/**
- ****************************************************************************
+/*****************************************************************************
* find a typed object and increment its refcount
*****************************************************************************
* This function recursively looks for a given object type. i_mode can be one
{
#ifndef NDEBUG
if (i_type == VLC_OBJECT_PLAYLIST)
- msg_Warn (p_this, "using vlc_object_find(VLC_OBJECT_PLAYLIST) "
- "instead of pl_Yield()");
+ 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);
return p_found;
}
+#undef vlc_object_find_name
/**
- ****************************************************************************
- * find a named object and increment its refcount
- *****************************************************************************
- * This function recursively looks for a given object name. i_mode can be one
- * of FIND_PARENT, FIND_CHILD or FIND_ANYWHERE.
- *****************************************************************************/
-void * __vlc_object_find_name( vlc_object_t *p_this, const char *psz_name,
- int i_mode )
+ * Finds a named object and increment its reference count.
+ * Beware that objects found in this manner can be "owned" by another thread,
+ * be of _any_ type, and be attached to any module (if any). With such an
+ * object reference, you can set or get object variables, emit log messages,
+ * and read write-once object parameters (psz_object_type, etc).
+ * You CANNOT cast the object to a more specific object type, and you
+ * definitely cannot invoke object type-specific callbacks with this.
+ *
+ * @param p_this object to search from
+ * @param psz_name name of the object to search for
+ * @param i_mode search direction: FIND_PARENT, FIND_CHILD or FIND_ANYWHERE.
+ *
+ * @return a matching object (must be released by the caller),
+ * or NULL on error.
+ */
+vlc_object_t *vlc_object_find_name( vlc_object_t *p_this,
+ const char *psz_name, int i_mode )
{
vlc_object_t *p_found;
}
/*****************************************************************************
- * decrement an object refcount
+ * Decrement an object refcount
* And destroy the object if its refcount reach zero.
*****************************************************************************/
void __vlc_object_release( vlc_object_t *p_this )
if( b_should_destroy )
{
+#ifndef NDEBUG
+ if( VLC_OBJECT(p_this->p_libvlc) == p_this )
+ {
+ /* Test for leaks */
+ vlc_object_t *leaked = internals->next;
+ while( leaked != p_this )
+ {
+ /* We are leaking this object */
+ fprintf( stderr,
+ "ERROR: leaking object (%p, type:%s, name:%s)\n",
+ leaked, leaked->psz_object_type,
+ leaked->psz_object_name );
+ /* Dump object to ease debugging */
+ vlc_object_dump( leaked );
+ fflush(stderr);
+ leaked = vlc_internals (leaked)->next;
+ }
+
+ if( internals->next != p_this )
+ /* Dump libvlc object to ease debugging */
+ vlc_object_dump( p_this );
+ }
+#endif
/* Remove the object from object list
* so that it cannot be encountered by vlc_object_get() */
vlc_internals (internals->next)->prev = internals->prev;
if( b_should_destroy )
{
+ int canc;
+
free( internals->pp_children );
internals->pp_children = NULL;
internals->i_children = 0;
+ canc = vlc_savecancel ();
vlc_object_destroy( p_this );
+ vlc_restorecancel (canc);
}
}
if( priv->i_children )
{
- priv->pp_children = (vlc_object_t **)realloc( priv->pp_children,
- priv->i_children * sizeof(vlc_object_t *) );
+ vlc_object_t **pp_children = (vlc_object_t **)
+ realloc( priv->pp_children,
+ priv->i_children * sizeof(vlc_object_t *) );
+ if( pp_children )
+ priv->pp_children = pp_children;
}
else
{
* 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,
+ return vlc_list_find ((vlc_object_t *)p_module_bank,
i_type, FIND_CHILD);
return vlc_list_find (p_this->p_libvlc, i_type, FIND_CHILD);
static int DumpCommand( vlc_object_t *p_this, char const *psz_cmd,
vlc_value_t oldval, vlc_value_t newval, void *p_data )
{
+ libvlc_int_t *p_libvlc = p_this->p_libvlc;
+
(void)oldval; (void)p_data;
if( *psz_cmd == 'l' )
{
- vlc_object_t *root = VLC_OBJECT (vlc_global ()), *cur = root;
+ vlc_object_t *cur = VLC_OBJECT (p_libvlc);
vlc_mutex_lock( &structure_lock );
do
PrintObject (cur, "");
cur = vlc_internals (cur)->next;
}
- while (cur != root);
+ while (cur != VLC_OBJECT(p_libvlc));
vlc_mutex_unlock( &structure_lock );
}
else
{
char *end;
int i_id = strtol( newval.psz_string, &end, 0 );
- 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 );
- }
- }
-
+ /* try using the object's name to find it */
+ p_object = vlc_object_find_name( p_this, newval.psz_string,
+ FIND_ANYWHERE );
if( !p_object )
{
return VLC_ENOOBJ;
char psz_foo[2 * MAX_DUMPSTRUCTURE_DEPTH + 1];
if( !p_object )
- p_object = p_this->p_libvlc ? VLC_OBJECT(p_this->p_libvlc) : p_this;
+ p_object = VLC_OBJECT(p_this->p_libvlc);
psz_foo[0] = '|';
DumpStructure( p_object, 0, psz_foo );
if( p_var->psz_text )
printf( ", %s", p_var->psz_text );
printf( ")" );
+ if( p_var->i_type & VLC_VAR_HASCHOICE )
+ printf( ", has choices" );
if( p_var->i_type & VLC_VAR_ISCOMMAND )
printf( ", command" );
if( p_var->i_entries )
printf( ", %d callbacks", p_var->i_entries );
- switch( p_var->i_type & 0x00f0 )
+ switch( p_var->i_type & VLC_VAR_CLASS )
{
case VLC_VAR_VOID:
case VLC_VAR_MUTEX:
/*****************************************************************************
* dump an object. (Debug function)
*****************************************************************************/
-void __vlc_object_dump( vlc_object_t *p_this )
+static void vlc_object_dump( vlc_object_t *p_this )
{
- vlc_mutex_lock( &structure_lock );
char psz_foo[2 * MAX_DUMPSTRUCTURE_DEPTH + 1];
psz_foo[0] = '|';
+
+ vlc_assert_locked( &structure_lock );
DumpStructure( p_this, 0, psz_foo );
- vlc_mutex_unlock( &structure_lock );
}
/* Following functions are local */
char psz_children[20], psz_refcount[20], psz_thread[30], psz_name[50],
psz_parent[20];
+ int canc = vlc_savecancel ();
memset( &psz_name, 0, sizeof(psz_name) );
if( p_this->psz_object_name )
{
psz_parent[0] = '\0';
if( p_this->p_parent )
- snprintf( psz_parent, 19, ", parent %i", p_this->p_parent->i_object_id );
+ snprintf( psz_parent, 19, ", parent %p", p_this->p_parent );
- printf( " %so %.8i %s%s%s%s%s%s\n", psz_prefix,
- p_this->i_object_id, p_this->psz_object_type,
+ printf( " %so %p %s%s%s%s%s%s\n", psz_prefix,
+ p_this, p_this->psz_object_type,
psz_name, psz_thread, psz_refcount, psz_children,
psz_parent );
+ vlc_restorecancel (canc);
}
static void DumpStructure( vlc_object_t *p_this, int i_level, char *psz_foo )
ListChildren( p_list, p_tmp, i_type );
}
}
-
-#ifndef NDEBUG
-void vlc_refcheck (vlc_object_t *obj)
-{
- static unsigned errors = 0;
- vlc_object_t *caller = vlc_threadobj ();
- vlc_object_internals_t *priv = vlc_internals (obj);
- int refs;
-
- if (errors > 100)
- return;
-
- if (!caller)
- return; /* main thread, not sure how to handle it */
-
- /* An object can always access itself without reference! */
- if (caller == obj)
- return;
-
- /* The calling thread is younger than the object.
- * Access could be valid, we would need more accounting. */
- if (caller->i_object_id > obj->i_object_id)
- return;
-
- 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;
-
- /* The parent of an object normally holds the unique reference.
- * As not all objects are threads, it could also be an ancestor. */
- vlc_mutex_lock (&structure_lock);
- for (vlc_object_t *cur = obj; cur != NULL; cur = cur->p_parent)
- if (cur == caller)
- {
- vlc_mutex_unlock (&structure_lock);
- return;
- }
- vlc_mutex_unlock (&structure_lock);
-
-#if 1
- if (caller->i_object_type == VLC_OBJECT_PLAYLIST)
- return; /* Playlist is too clever, or hopelessly broken. */
-#endif
- msg_Err (caller, "This thread is accessing...");
- msg_Err (obj, "...this object in a suspicious manner.");
-
- if (++errors == 100)
- msg_Err (caller, "Too many reference errors");
-}
-#endif
projects / vlc / blobdiff