/*****************************************************************************
* objects.c: vlc_object_t handling
*****************************************************************************
* Copyright (C) 2004-2008 the VideoLAN team
*
* Authors: Samuel Hocevar <sam@zoy.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
*****************************************************************************/
/**
* \file
* This file contains the functions to handle the vlc_object_t type
*/
/*****************************************************************************
* Preamble
*****************************************************************************/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include "vlc_common.h"
#include "libvlc.h"
#include "vlc_vout.h"
#include "vlc_aout.h"
#include "audio_output/aout_internal.h"
#include "vlc_access.h"
#include "vlc_demux.h"
#include "vlc_stream.h"
#include "vlc_sout.h"
#include "stream_output/stream_output.h"
#include "vlc_interface.h"
#include "vlc_codec.h"
#include "vlc_filter.h"
#include "variables.h"
#ifndef WIN32
# include <unistd.h>
#else
# include <io.h>
# include <fcntl.h>
# include <errno.h> /* ENOSYS */
#endif
#include <assert.h>
/*****************************************************************************
* Local prototypes
*****************************************************************************/
static int DumpCommand( vlc_object_t *, char const *,
vlc_value_t, vlc_value_t, void * );
static vlc_object_t * FindObject ( vlc_object_t *, int, int );
static vlc_object_t * FindObjectName( vlc_object_t *, const char *, int );
static void PrintObject ( vlc_object_t *, const char * );
static void DumpStructure ( vlc_object_t *, int, char * );
static vlc_list_t * NewList ( int );
static void ListReplace ( vlc_list_t *, vlc_object_t *, int );
/*static void ListAppend ( vlc_list_t *, vlc_object_t * );*/
static int CountChildren ( 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_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 unsigned object_counter = 0;
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;
/* NOTE:
* VLC objects are laid out as follow:
* - first the LibVLC-private per-object data,
* - then VLC_COMMON members from vlc_object_t,
* - finally, the type-specific data (if any).
*
* This function initializes the LibVLC and common data,
* and zeroes the rest.
*/
p_priv = calloc( 1, sizeof( *p_priv ) + i_size );
if( p_priv == NULL )
return NULL;
assert (i_size >= sizeof (vlc_object_t));
p_new = (vlc_object_t *)(p_priv + 1);
p_new->i_object_type = i_type;
p_new->psz_object_type = psz_type;
p_new->psz_object_name = NULL;
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;
if (p_this)
p_new->i_flags = p_this->i_flags
& (OBJECT_FLAGS_NODBG|OBJECT_FLAGS_QUIET|OBJECT_FLAGS_NOINTERACT);
p_priv->p_vars = calloc( sizeof( variable_t ), 16 );
if( !p_priv->p_vars )
{
free( p_priv );
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;
object_counter = 0; /* reset */
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;
else
p_new->p_libvlc = p_this->p_libvlc;
}
vlc_spin_init( &p_priv->ref_spin );
p_priv->i_refcount = 1;
p_priv->pf_destructor = NULL;
p_priv->b_thread = false;
p_new->p_parent = NULL;
p_priv->pp_children = NULL;
p_priv->i_children = 0;
p_new->p_private = NULL;
/* Initialize mutexes and condvars */
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 = object_counter++; /* fetch THEN increment */
vlc_mutex_unlock( &structure_lock );
if( i_type == VLC_OBJECT_LIBVLC )
{
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 );
}
return p_new;
}
/**
* Allocates and initializes a vlc object.
*
* @param i_type known object type (all of them are negative integer values),
* or object byte size (always positive).
*
* @return the new object, or NULL on error.
*/
void * __vlc_object_create( vlc_object_t *p_this, int i_type )
{
const char * psz_type;
size_t i_size;
switch( i_type )
{
case VLC_OBJECT_INTF:
i_size = sizeof(intf_thread_t);
psz_type = "interface";
break;
case VLC_OBJECT_DECODER:
i_size = sizeof(decoder_t);
psz_type = "decoder";
break;
case VLC_OBJECT_PACKETIZER:
i_size = sizeof(decoder_t);
psz_type = "packetizer";
break;
case VLC_OBJECT_ENCODER:
i_size = sizeof(encoder_t);
psz_type = "encoder";
break;
case VLC_OBJECT_AOUT:
i_size = sizeof(aout_instance_t);
psz_type = "audio 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;
default:
assert( i_type > 0 ); /* unknown type?! */
i_size = i_type;
i_type = VLC_OBJECT_GENERIC;
psz_type = "generic";
break;
}
return vlc_custom_create( p_this, i_size, i_type, psz_type );
}
/**
****************************************************************************
* Set the destructor of a vlc object
*
* This function sets the destructor of the vlc object. It will be called
* when the object is destroyed when the its refcount reaches 0.
* (It is called by the internal function vlc_object_destroy())
*****************************************************************************/
void __vlc_object_set_destructor( vlc_object_t *p_this,
vlc_destructor_t pf_destructor )
{
vlc_object_internals_t *p_priv = vlc_internals(p_this );
p_priv->pf_destructor = pf_destructor;
}
/**
****************************************************************************
* Destroy a vlc object (Internal)
*
* 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.
*****************************************************************************/
static void vlc_object_destroy( vlc_object_t *p_this )
{
vlc_object_internals_t *p_priv = vlc_internals( 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 );
/* Destroy the associated variables, starting from the end so that
* no memmove calls have to be done. */
while( p_priv->i_vars )
{
var_Destroy( p_this, p_priv->p_vars[p_priv->i_vars - 1].psz_name );
}
free( p_priv->p_vars );
vlc_mutex_destroy( &p_priv->var_lock );
free( p_this->psz_header );
if( p_this->p_libvlc == NULL )
{
#ifndef NDEBUG
libvlc_global_data_t *p_global = (libvlc_global_data_t *)p_this;
assert( p_global == vlc_global() );
/* Test for leaks */
if (p_priv->next != p_this)
{
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",
leaked->i_object_id, leaked->psz_object_type,
leaked->psz_object_name );
/* Dump libvlc object to ease debugging */
vlc_object_dump( leaked );
fflush(stderr);
leaked = vlc_internals (leaked)->next;
}
while (leaked != first);
/* 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. */
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 )
CloseHandle(p_priv->thread_id);
#endif
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] );
if( p_priv->pipes[0] != -1 )
close( p_priv->pipes[0] );
free( p_priv );
}
/** Inter-object signaling */
void __vlc_object_lock( vlc_object_t *obj )
{
vlc_mutex_lock( &(vlc_internals(obj)->lock) );
}
void __vlc_object_unlock( vlc_object_t *obj )
{
vlc_assert_locked( &(vlc_internals(obj)->lock) );
vlc_mutex_unlock( &(vlc_internals(obj)->lock) );
}
#ifdef WIN32
# include <winsock2.h>
# include <ws2tcpip.h>
/**
* select()-able pipes emulated using Winsock
*/
static int pipe (int fd[2])
{
SOCKADDR_IN addr;
int addrlen = sizeof (addr);
SOCKET l = socket (PF_INET, SOCK_STREAM, IPPROTO_TCP), a,
c = socket (PF_INET, SOCK_STREAM, IPPROTO_TCP);
if ((l == INVALID_SOCKET) || (c == INVALID_SOCKET))
goto error;
memset (&addr, 0, sizeof (addr));
addr.sin_family = AF_INET;
addr.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
if (bind (l, (PSOCKADDR)&addr, sizeof (addr))
|| getsockname (l, (PSOCKADDR)&addr, &addrlen)
|| listen (l, 1)
|| connect (c, (PSOCKADDR)&addr, addrlen))
goto error;
a = accept (l, NULL, NULL);
if (a == INVALID_SOCKET)
goto error;
closesocket (l);
//shutdown (a, 0);
//shutdown (c, 1);
fd[0] = c;
fd[1] = a;
return 0;
error:
if (l != INVALID_SOCKET)
closesocket (l);
if (c != INVALID_SOCKET)
closesocket (c);
return -1;
}
#undef read
#define read( a, b, c ) recv (a, b, c, 0)
#undef write
#define write( a, b, c ) send (a, b, c, 0)
#undef close
#define close( a ) closesocket (a)
#endif /* WIN32 */
/**
* Returns the readable end of a pipe that becomes readable once termination
* of the object is requested (vlc_object_kill()).
* This can be used to wake-up out of a select() or poll() event loop, such
* typically when doing network I/O.
*
* Note that the pipe will remain the same for the lifetime of the object.
* DO NOT read the pipe nor close it yourself. Ever.
*
* @param obj object that would be "killed"
* @return a readable pipe descriptor, or -1 on error.
*/
int __vlc_object_waitpipe( vlc_object_t *obj )
{
int pfd[2] = { -1, -1 };
vlc_object_internals_t *internals = vlc_internals( obj );
bool killed = false;
vlc_spin_lock (&internals->spin);
if (internals->pipes[0] == -1)
{
/* This can only ever happen if someone killed us without locking: */
assert (internals->pipes[1] == -1);
vlc_spin_unlock (&internals->spin);
if (pipe (pfd))
return -1;
vlc_spin_lock (&internals->spin);
if (internals->pipes[0] == -1)
{
internals->pipes[0] = pfd[0];
internals->pipes[1] = pfd[1];
pfd[0] = pfd[1] = -1;
}
killed = obj->b_die;
}
vlc_spin_unlock (&internals->spin);
if (killed)
{
/* Race condition: vlc_object_kill() already invoked! */
int fd;
vlc_spin_lock (&internals->spin);
fd = internals->pipes[1];
internals->pipes[1] = -1;
vlc_spin_unlock (&internals->spin);
msg_Dbg (obj, "waitpipe: object already dying");
if (fd != -1)
close (fd);
}
/* Race condition: two threads call pipe() - unlikely */
if (pfd[0] != -1)
close (pfd[0]);
if (pfd[1] != -1)
close (pfd[1]);
return internals->pipes[0];
}
/**
* Waits for the object to be signaled (using vlc_object_signal()).
* 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.
*/
void __vlc_object_wait( vlc_object_t *obj )
{
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. It is asserted that the caller holds the object lock.
*
* @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 )
{
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 (&(vlc_internals(obj)->lock));
vlc_cond_signal( &(vlc_internals(obj)->wait) );
}
/**
* Requests termination of an object.
* If the object is LibVLC, also request to terminate all its children.
*/
void __vlc_object_kill( vlc_object_t *p_this )
{
vlc_object_internals_t *priv = vlc_internals( p_this );
int fd;
vlc_object_lock( p_this );
p_this->b_die = true;
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);
}
vlc_object_signal_unlocked( p_this );
/* 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;
#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 );
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;
#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;
}
/**
****************************************************************************
* find a typed object and increment its refcount
*****************************************************************************
* This function recursively looks for a given object type. i_mode can be one
* of FIND_PARENT, FIND_CHILD or FIND_ANYWHERE.
*****************************************************************************/
void * __vlc_object_find( vlc_object_t *p_this, int i_type, int i_mode )
{
vlc_object_t *p_found;
/* 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_object_yield( p_this );
return p_this;
}
/* Otherwise, recursively look for the object */
if ((i_mode & 0x000f) == FIND_ANYWHERE)
{
#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;
}
/**
****************************************************************************
* 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 )
{
vlc_object_t *p_found;
/* 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_object_yield( p_this );
return p_this;
}
vlc_mutex_lock( &structure_lock );
/* Otherwise, recursively look for the object */
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 = FindObjectName( p_root, psz_name,
(i_mode & ~0x000f)|FIND_CHILD );
if( p_found == NULL && p_root != VLC_OBJECT( p_this->p_libvlc ) )
{
p_found = FindObjectName( VLC_OBJECT( p_this->p_libvlc ),
psz_name, (i_mode & ~0x000f)|FIND_CHILD );
}
}
else
{
p_found = FindObjectName( p_this, psz_name, i_mode );
}
vlc_mutex_unlock( &structure_lock );
return p_found;
}
/**
* Increment an object reference counter.
*/
void __vlc_object_yield( vlc_object_t *p_this )
{
vlc_object_internals_t *internals = vlc_internals( p_this );
vlc_spin_lock( &internals->ref_spin );
/* Avoid obvious freed object uses */
assert( internals->i_refcount > 0 );
/* 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
}
/*****************************************************************************
* 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;
#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 );
/* 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 )
{
/* 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 );
}
}
/**
****************************************************************************
* attach object to a parent object
*****************************************************************************
* This function sets p_this as a child of p_parent, and p_parent as a parent
* of p_this. This link can be undone using vlc_object_detach.
*****************************************************************************/
void __vlc_object_attach( vlc_object_t *p_this, vlc_object_t *p_parent )
{
if( !p_this ) return;
vlc_mutex_lock( &structure_lock );
/* Attach the parent to its child */
assert (!p_this->p_parent);
p_this->p_parent = p_parent;
/* Attach the child to its parent */
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;
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-- ; )
{
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];
}
}
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
*****************************************************************************
* This function removes all links between an object and its parent.
*****************************************************************************/
void __vlc_object_detach( vlc_object_t *p_this )
{
if( !p_this ) return;
vlc_mutex_lock( &structure_lock );
if( !p_this->p_parent )
msg_Err( p_this, "object is not attached" );
else
vlc_object_detach_unlocked( p_this );
vlc_mutex_unlock( &structure_lock );
}
/**
****************************************************************************
* find a list typed objects and increment their refcount
*****************************************************************************
* This function recursively looks for a given object type. i_mode can be one
* of FIND_PARENT, FIND_CHILD or FIND_ANYWHERE.
*****************************************************************************/
vlc_list_t * __vlc_list_find( vlc_object_t *p_this, int i_type, int i_mode )
{
vlc_list_t *p_list;
int i_count = 0;
/* Look for the objects */
switch( i_mode & 0x000f )
{
case FIND_ANYWHERE:
/* 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:
msg_Err( p_this, "unimplemented!" );
p_list = NewList( 0 );
break;
}
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
*****************************************************************************
* This function prints either an ASCII tree showing the connections between
* vlc objects, and additional information such as their refcount, thread ID,
* etc. (command "tree"), or the same data as a simple list (command "list").
*****************************************************************************/
static int DumpCommand( vlc_object_t *p_this, char const *psz_cmd,
vlc_value_t oldval, vlc_value_t newval, void *p_data )
{
(void)oldval; (void)p_data;
if( *psz_cmd == 'l' )
{
vlc_object_t *root = VLC_OBJECT (vlc_global ()), *cur = root;
vlc_mutex_lock( &structure_lock );
do
{
PrintObject (cur, "");
cur = vlc_internals (cur)->next;
}
while (cur != root);
vlc_mutex_unlock( &structure_lock );
}
else
{
vlc_object_t *p_object = NULL;
if( *newval.psz_string )
{
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 */
p_object = vlc_object_find_name( p_this, newval.psz_string,
FIND_ANYWHERE );
if( !p_object )
{
return VLC_ENOOBJ;
}
}
vlc_mutex_lock( &structure_lock );
if( *psz_cmd == 't' )
{
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;
psz_foo[0] = '|';
DumpStructure( p_object, 0, psz_foo );
}
else if( *psz_cmd == 'v' )
{
int i;
if( !p_object )
p_object = p_this->p_libvlc ? VLC_OBJECT(p_this->p_libvlc) : p_this;
PrintObject( p_object, "" );
if( !vlc_internals( p_object )->i_vars )
printf( " `-o No variables\n" );
for( i = 0; i < vlc_internals( p_object )->i_vars; i++ )
{
variable_t *p_var = vlc_internals( p_object )->p_vars + i;
const char *psz_type = "unknown";
switch( p_var->i_type & VLC_VAR_TYPE )
{
#define MYCASE( type, nice ) \
case VLC_VAR_ ## type: \
psz_type = nice; \
break;
MYCASE( VOID, "void" );
MYCASE( BOOL, "bool" );
MYCASE( INTEGER, "integer" );
MYCASE( HOTKEY, "hotkey" );
MYCASE( STRING, "string" );
MYCASE( MODULE, "module" );
MYCASE( FILE, "file" );
MYCASE( DIRECTORY, "directory" );
MYCASE( VARIABLE, "variable" );
MYCASE( FLOAT, "float" );
MYCASE( TIME, "time" );
MYCASE( ADDRESS, "address" );
MYCASE( MUTEX, "mutex" );
MYCASE( LIST, "list" );
#undef MYCASE
}
printf( " %c-o \"%s\" (%s",
i + 1 == vlc_internals( p_object )->i_vars ? '`' : '|',
p_var->psz_name, psz_type );
if( p_var->psz_text )
printf( ", %s", p_var->psz_text );
printf( ")" );
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 )
{
case VLC_VAR_VOID:
case VLC_VAR_MUTEX:
break;
case VLC_VAR_BOOL:
printf( ": %s", p_var->val.b_bool ? "true" : "false" );
break;
case VLC_VAR_INTEGER:
printf( ": %d", p_var->val.i_int );
break;
case VLC_VAR_STRING:
printf( ": \"%s\"", p_var->val.psz_string );
break;
case VLC_VAR_FLOAT:
printf( ": %f", p_var->val.f_float );
break;
case VLC_VAR_TIME:
printf( ": %"PRIi64, (int64_t)p_var->val.i_time );
break;
case VLC_VAR_ADDRESS:
printf( ": %p", p_var->val.p_address );
break;
case VLC_VAR_LIST:
printf( ": TODO" );
break;
}
printf( "\n" );
}
}
vlc_mutex_unlock( &structure_lock );
if( *newval.psz_string )
{
vlc_object_release( p_object );
}
}
return VLC_SUCCESS;
}
/*****************************************************************************
* vlc_list_release: free a list previously allocated by vlc_list_find
*****************************************************************************
* This function decreases the refcount of all objects in the list and
* frees the list.
*****************************************************************************/
void vlc_list_release( vlc_list_t *p_list )
{
int i_index;
for( i_index = 0; i_index < p_list->i_count; i_index++ )
{
vlc_object_release( p_list->p_values[i_index].p_object );
}
free( p_list->p_values );
free( p_list );
}
/*****************************************************************************
* dump an object. (Debug function)
*****************************************************************************/
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] = '|';
DumpStructure( p_this, 0, psz_foo );
vlc_mutex_unlock( &structure_lock );
}
/* Following functions are local */
static vlc_object_t * FindObject( vlc_object_t *p_this, int i_type, int i_mode )
{
int i;
vlc_object_t *p_tmp;
switch( i_mode & 0x000f )
{
case FIND_PARENT:
p_tmp = p_this->p_parent;
if( p_tmp )
{
if( p_tmp->i_object_type == i_type )
{
vlc_object_yield( p_tmp );
return p_tmp;
}
else
{
return FindObject( p_tmp, i_type, i_mode );
}
}
break;
case FIND_CHILD:
for( i = vlc_internals( p_this )->i_children; i--; )
{
p_tmp = vlc_internals( p_this )->pp_children[i];
if( p_tmp->i_object_type == i_type )
{
vlc_object_yield( p_tmp );
return p_tmp;
}
else if( vlc_internals( p_tmp )->i_children )
{
p_tmp = FindObject( p_tmp, i_type, i_mode );
if( p_tmp )
{
return p_tmp;
}
}
}
break;
case FIND_ANYWHERE:
/* Handled in vlc_object_find */
break;
}
return NULL;
}
static vlc_object_t * FindObjectName( vlc_object_t *p_this,
const char *psz_name,
int i_mode )
{
int i;
vlc_object_t *p_tmp;
switch( i_mode & 0x000f )
{
case FIND_PARENT:
p_tmp = p_this->p_parent;
if( p_tmp )
{
if( p_tmp->psz_object_name
&& !strcmp( p_tmp->psz_object_name, psz_name ) )
{
vlc_object_yield( p_tmp );
return p_tmp;
}
else
{
return FindObjectName( p_tmp, psz_name, i_mode );
}
}
break;
case FIND_CHILD:
for( i = vlc_internals( p_this )->i_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_object_yield( p_tmp );
return p_tmp;
}
else if( vlc_internals( p_tmp )->i_children )
{
p_tmp = FindObjectName( p_tmp, psz_name, i_mode );
if( p_tmp )
{
return p_tmp;
}
}
}
break;
case FIND_ANYWHERE:
/* Handled in vlc_object_find */
break;
}
return NULL;
}
static void PrintObject( vlc_object_t *p_this, const char *psz_prefix )
{
char psz_children[20], psz_refcount[20], psz_thread[30], psz_name[50],
psz_parent[20];
memset( &psz_name, 0, sizeof(psz_name) );
if( p_this->psz_object_name )
{
snprintf( psz_name, 49, " \"%s\"", p_this->psz_object_name );
if( psz_name[48] )
psz_name[48] = '\"';
}
psz_children[0] = '\0';
switch( vlc_internals( p_this )->i_children )
{
case 0:
break;
case 1:
strcpy( psz_children, ", 1 child" );
break;
default:
snprintf( psz_children, 19, ", %i children",
vlc_internals( p_this )->i_children );
break;
}
psz_refcount[0] = '\0';
if( vlc_internals( p_this )->i_refcount > 0 )
snprintf( psz_refcount, 19, ", refcount %u",
vlc_internals( p_this )->i_refcount );
psz_thread[0] = '\0';
if( vlc_internals( p_this )->b_thread )
snprintf( psz_thread, 29, " (thread %lu)",
(unsigned long)vlc_internals( p_this )->thread_id );
psz_parent[0] = '\0';
if( p_this->p_parent )
snprintf( psz_parent, 19, ", parent %i", p_this->p_parent->i_object_id );
printf( " %so %.8i %s%s%s%s%s%s\n", psz_prefix,
p_this->i_object_id, p_this->psz_object_type,
psz_name, psz_thread, psz_refcount, psz_children,
psz_parent );
}
static void DumpStructure( vlc_object_t *p_this, int i_level, char *psz_foo )
{
int i;
char i_back = psz_foo[i_level];
psz_foo[i_level] = '\0';
PrintObject( p_this, psz_foo );
psz_foo[i_level] = i_back;
if( i_level / 2 >= MAX_DUMPSTRUCTURE_DEPTH )
{
msg_Warn( p_this, "structure tree is too deep" );
return;
}
for( i = 0 ; i < vlc_internals( p_this )->i_children ; i++ )
{
if( i_level )
{
psz_foo[i_level-1] = ' ';
if( psz_foo[i_level-2] == '`' )
{
psz_foo[i_level-2] = ' ';
}
}
if( i == vlc_internals( p_this )->i_children - 1 )
{
psz_foo[i_level] = '`';
}
else
{
psz_foo[i_level] = '|';
}
psz_foo[i_level+1] = '-';
psz_foo[i_level+2] = '\0';
DumpStructure( vlc_internals( p_this )->pp_children[i], i_level + 2,
psz_foo );
}
}
static vlc_list_t * NewList( int i_count )
{
vlc_list_t * p_list = (vlc_list_t *)malloc( sizeof( vlc_list_t ) );
if( p_list == NULL )
{
return NULL;
}
p_list->i_count = i_count;
if( i_count == 0 )
{
p_list->p_values = NULL;
return p_list;
}
p_list->p_values = malloc( i_count * sizeof( vlc_value_t ) );
if( p_list->p_values == NULL )
{
p_list->i_count = 0;
return p_list;
}
return p_list;
}
static void ListReplace( vlc_list_t *p_list, vlc_object_t *p_object,
int i_index )
{
if( p_list == NULL || i_index >= p_list->i_count )
{
return;
}
vlc_object_yield( p_object );
p_list->p_values[i_index].p_object = p_object;
return;
}
/*static void ListAppend( vlc_list_t *p_list, vlc_object_t *p_object )
{
if( p_list == NULL )
{
return;
}
p_list->p_values = realloc( p_list->p_values, (p_list->i_count + 1)
* sizeof( vlc_value_t ) );
if( p_list->p_values == NULL )
{
p_list->i_count = 0;
return;
}
vlc_object_yield( p_object );
p_list->p_values[p_list->i_count].p_object = p_object;
p_list->i_count++;
return;
}*/
static int CountChildren( vlc_object_t *p_this, int i_type )
{
vlc_object_t *p_tmp;
int i, i_count = 0;
for( i = 0; i < vlc_internals( p_this )->i_children; i++ )
{
p_tmp = vlc_internals( p_this )->pp_children[i];
if( p_tmp->i_object_type == i_type )
{
i_count++;
}
i_count += CountChildren( p_tmp, i_type );
}
return i_count;
}
static void ListChildren( vlc_list_t *p_list, vlc_object_t *p_this, int i_type )
{
vlc_object_t *p_tmp;
int i;
for( i = 0; i < vlc_internals( p_this )->i_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++ );
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
