/*****************************************************************************
* objects.c: vlc_object_t handling
*****************************************************************************
- * Copyright (C) 2004-2008 the VideoLAN team
+ * Copyright (C) 2004-2008 VLC authors and VideoLAN
* Copyright (C) 2006-2010 RĂ©mi Denis-Courmont
*
* 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
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 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.
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser 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.
+ * You should have received a copy of the GNU Lesser 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.
*****************************************************************************/
/**
# include <search.h>
#endif
-#ifndef WIN32
-# include <vlc_fs.h>
-# include <unistd.h>
-#else
+#ifdef __OS2__
+# include <sys/socket.h>
+# include <netinet/in.h>
+# include <unistd.h> // close(), write()
+#elif defined(WIN32)
# include <io.h>
# include <winsock2.h>
# include <ws2tcpip.h>
# define write( a, b, c ) send (a, b, c, 0)
# undef close
# define close( a ) closesocket (a)
+#else
+# include <vlc_fs.h>
+# include <unistd.h>
#endif
#include <limits.h>
static int DumpCommand( vlc_object_t *, char const *,
vlc_value_t, vlc_value_t, void * );
-static vlc_object_t * FindParentName( vlc_object_t *, const char * );
-static vlc_object_t * FindChildName ( vlc_object_internals_t *, const char * );
+static vlc_object_t * FindName ( vlc_object_internals_t *, const char * );
static void PrintObject( vlc_object_internals_t *, const char * );
static void DumpStructure( vlc_object_internals_t *, unsigned, char * );
}
#undef vlc_custom_create
-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 *parent, size_t length,
+ const char *typename)
{
- 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,
* 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);
+ assert (length >= sizeof (vlc_object_t));
- p_priv->i_object_type = i_type;
- p_new->psz_object_type = psz_type;
- p_priv->psz_name = NULL;
+ vlc_object_internals_t *priv = malloc (sizeof (*priv) + length);
+ if (unlikely(priv == NULL))
+ return NULL;
+ priv->psz_name = NULL;
+ priv->var_root = NULL;
+ vlc_mutex_init (&priv->var_lock);
+ vlc_cond_init (&priv->var_wait);
+ priv->pipes[0] = priv->pipes[1] = -1;
+ atomic_init (&priv->alive, true);
+ atomic_init (&priv->refs, 1);
+ priv->pf_destructor = NULL;
+ priv->prev = NULL;
+ priv->first = NULL;
- p_new->b_die = false;
- p_new->b_force = false;
+ vlc_object_t *obj = (vlc_object_t *)(priv + 1);
+ obj->psz_object_type = typename;
+ obj->psz_header = NULL;
+ obj->b_force = false;
+ memset (obj + 1, 0, length - sizeof (*obj)); /* type-specific stuff */
- p_new->psz_header = NULL;
+ if (likely(parent != NULL))
+ {
+ vlc_object_internals_t *papriv = vlc_internals (parent);
- if (p_this)
- p_new->i_flags = p_this->i_flags
- & (OBJECT_FLAGS_NODBG|OBJECT_FLAGS_QUIET|OBJECT_FLAGS_NOINTERACT);
+ obj->i_flags = parent->i_flags;
+ obj->p_libvlc = parent->p_libvlc;
- p_priv->var_root = NULL;
+ /* Attach the child to its parent (no lock needed) */
+ obj->p_parent = vlc_object_hold (parent);
- if( p_this == NULL )
- {
- libvlc_int_t *self = (libvlc_int_t*)p_new;
- p_new->p_libvlc = self;
- vlc_mutex_init (&(libvlc_priv (self)->structure_lock));
- p_this = p_new;
+ /* Attach the parent to its child (structure lock needed) */
+ libvlc_lock (obj->p_libvlc);
+ priv->next = papriv->first;
+ if (priv->next != NULL)
+ priv->next->prev = priv;
+ papriv->first = priv;
+ libvlc_unlock (obj->p_libvlc);
}
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_new->p_parent = NULL;
- p_priv->first = NULL;
+ {
+ libvlc_int_t *self = (libvlc_int_t *)obj;
- /* Initialize mutexes and condvars */
- vlc_mutex_init( &p_priv->var_lock );
- vlc_cond_init( &p_priv->var_wait );
- p_priv->pipes[0] = p_priv->pipes[1] = -1;
+ obj->i_flags = 0;
+ obj->p_libvlc = self;
+ obj->p_parent = NULL;
+ priv->next = NULL;
+ vlc_mutex_init (&(libvlc_priv (self)->structure_lock));
- if (p_new == VLC_OBJECT(p_new->p_libvlc))
- { /* TODO: should be in src/libvlc.c */
+ /* TODO: should be in src/libvlc.c */
int canc = vlc_savecancel ();
- 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 );
+ var_Create (obj, "tree", VLC_VAR_STRING | VLC_VAR_ISCOMMAND);
+ var_AddCallback (obj, "tree", DumpCommand, obj);
+ var_Create (obj, "vars", VLC_VAR_STRING | VLC_VAR_ISCOMMAND);
+ var_AddCallback (obj, "vars", DumpCommand, obj);
vlc_restorecancel (canc);
}
- return p_new;
+ return obj;
}
#undef vlc_object_create
*/
void *vlc_object_create( vlc_object_t *p_this, size_t i_size )
{
- return vlc_custom_create( p_this, i_size, VLC_OBJECT_GENERIC, "generic" );
+ return vlc_custom_create( p_this, i_size, "generic" );
}
#undef vlc_object_set_destructor
{
vlc_object_internals_t *p_priv = vlc_internals(p_this );
- vlc_spin_lock( &p_priv->ref_spin );
p_priv->pf_destructor = pf_destructor;
- vlc_spin_unlock( &p_priv->ref_spin );
}
static vlc_mutex_t name_lock = VLC_STATIC_MUTEX;
}
/**
- ****************************************************************************
- * 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.
+ * Destroys a VLC object once it has no more references.
*
* This function must be called with cancellation disabled (currently).
- *****************************************************************************/
+ */
static void vlc_object_destroy( vlc_object_t *p_this )
{
vlc_object_internals_t *p_priv = vlc_internals( p_this );
- /* Send a kill to the object's thread if applicable */
- vlc_object_kill( p_this );
-
/* Call the custom "subclass" destructor */
if( p_priv->pf_destructor )
p_priv->pf_destructor( p_this );
+ if (unlikely(p_this == VLC_OBJECT(p_this->p_libvlc)))
+ {
+ /* TODO: should be in src/libvlc.c */
+ var_DelCallback (p_this, "tree", DumpCommand, p_this);
+ var_DelCallback (p_this, "vars", DumpCommand, p_this);
+ }
+
/* Destroy the associated variables. */
var_DestroyAll( p_this );
free( p_priv->psz_name );
- vlc_spin_destroy( &p_priv->ref_spin );
if( p_priv->pipes[1] != -1 && p_priv->pipes[1] != p_priv->pipes[0] )
close( p_priv->pipes[1] );
if( p_priv->pipes[0] != -1 )
}
-#ifdef WIN32
+#if defined(WIN32) || defined(__OS2__)
/**
* select()-able pipes emulated using Winsock
*/
# define vlc_pipe selectable_pipe
static int selectable_pipe (int fd[2])
{
- SOCKADDR_IN addr;
+ struct 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))
+ int l = socket (PF_INET, SOCK_STREAM, IPPROTO_TCP),
+ c = socket (PF_INET, SOCK_STREAM, IPPROTO_TCP);
+ if (l == -1 || c == -1)
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)
+ if (bind (l, (struct sockaddr *)&addr, sizeof (addr))
+ || getsockname (l, (struct sockaddr *)&addr, &addrlen)
|| listen (l, 1)
- || connect (c, (PSOCKADDR)&addr, addrlen))
+ || connect (c, (struct sockaddr *)&addr, addrlen))
goto error;
- a = accept (l, NULL, NULL);
- if (a == INVALID_SOCKET)
+ int a = accept (l, NULL, NULL);
+ if (a == -1)
goto error;
- closesocket (l);
+ close (l);
//shutdown (a, 0);
//shutdown (c, 1);
fd[0] = c;
return 0;
error:
- if (l != INVALID_SOCKET)
- closesocket (l);
- if (c != INVALID_SOCKET)
- closesocket (c);
+ if (l != -1)
+ close (l);
+ if (c != -1)
+ close (c);
return -1;
}
-#endif /* WIN32 */
+#endif /* WIN32 || __OS2__ */
static vlc_mutex_t pipe_lock = VLC_STATIC_MUTEX;
internals->pipes[0] = internals->pipes[1] = -1;
}
- if (internals->pipes[0] != -1 && obj->b_die)
+ if (internals->pipes[0] != -1 && !atomic_load (&internals->alive))
{ /* Race condition: vlc_object_kill() already invoked! */
msg_Dbg (obj, "waitpipe: object already dying");
write (internals->pipes[1], &(uint64_t){ 1 }, sizeof (uint64_t));
vlc_object_internals_t *priv = vlc_internals( p_this );
int fd = -1;
- vlc_mutex_lock( &pipe_lock );
- if( !p_this->b_die )
+ if (atomic_exchange (&priv->alive, false))
{
+ vlc_mutex_lock (&pipe_lock);
fd = priv->pipes[1];
- p_this->b_die = true;
+ vlc_mutex_unlock (&pipe_lock);
}
- /* This also serves as a memory barrier toward vlc_object_alive(): */
- vlc_mutex_unlock( &pipe_lock );
-
if (fd != -1)
{
int canc = vlc_savecancel ();
}
}
-static int objnamecmp(const vlc_object_t *obj, const char *name)
-{
- char *objname = vlc_object_get_name(obj);
- if (objname == NULL)
- return INT_MIN;
-
- int ret = strcmp (objname, name);
- free (objname);
- return ret;
-}
-
#undef vlc_object_find_name
/**
* Finds a named object and increment its reference count.
*
* @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 *vlc_object_find_name( vlc_object_t *p_this, const char *psz_name )
{
vlc_object_t *p_found;
/* Reading psz_object_name from a separate inhibits thread-safety.
* Use a libvlc address variable instead for that sort of things! */
- msg_Warn( p_this, "%s(%s) is not safe!", __func__, psz_name );
- /* If have the requested name ourselves, don't look further */
- if( !objnamecmp(p_this, psz_name) )
- {
- vlc_object_hold( p_this );
- return p_this;
- }
-
- /* Otherwise, recursively look for the object */
- if (i_mode == FIND_ANYWHERE)
- return vlc_object_find_name (VLC_OBJECT(p_this->p_libvlc), psz_name,
- FIND_CHILD);
+ msg_Err( p_this, "%s(\"%s\") is not safe!", __func__, psz_name );
libvlc_lock (p_this->p_libvlc);
vlc_mutex_lock (&name_lock);
- switch (i_mode)
- {
- case FIND_PARENT:
- p_found = FindParentName (p_this, psz_name);
- break;
- case FIND_CHILD:
- p_found = FindChildName (vlc_internals (p_this), psz_name);
- break;
- default:
- assert (0);
- }
+ p_found = FindName (vlc_internals (p_this), psz_name);
vlc_mutex_unlock (&name_lock);
libvlc_unlock (p_this->p_libvlc);
return p_found;
void * vlc_object_hold( vlc_object_t *p_this )
{
vlc_object_internals_t *internals = vlc_internals( p_this );
+ unsigned refs = atomic_fetch_add (&internals->refs, 1);
- 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 );
+ assert (refs > 0); /* Avoid obvious freed object uses */ (void) refs;
return p_this;
}
#undef vlc_object_release
-/*****************************************************************************
- * Decrement an object refcount
- * And destroy the object if its refcount reach zero.
- *****************************************************************************/
+/**
+ * Drops a reference to an object (decrements the reference count).
+ * If the count reaches zero, the object is destroyed.
+ */
void vlc_object_release( vlc_object_t *p_this )
{
vlc_object_internals_t *internals = vlc_internals( p_this );
vlc_object_t *parent = NULL;
- bool b_should_destroy;
+ unsigned refs = atomic_load (&internals->refs);
- vlc_spin_lock( &internals->ref_spin );
- assert( internals->i_refcount > 0 );
-
- if( internals->i_refcount > 1 )
+ /* Fast path */
+ while (refs > 1)
{
- /* Fast path */
- /* There are still other references to the object */
- internals->i_refcount--;
- vlc_spin_unlock( &internals->ref_spin );
- return;
+ if (atomic_compare_exchange_weak (&internals->refs, &refs, refs - 1))
+ return; /* There are still other references to the object */
+
+ assert (refs > 0);
}
- vlc_spin_unlock( &internals->ref_spin );
/* Slow path */
- /* Remember that we cannot hold the spin while waiting on the mutex */
libvlc_lock (p_this->p_libvlc);
- /* Take the spin again. Note that another thread may have held 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 );
+ refs = atomic_fetch_sub (&internals->refs, 1);
+ assert (refs > 0);
- if( b_should_destroy )
+ if (likely(refs == 1))
{
- /* Detach from parent to protect against FIND_CHILDREN */
+ /* Detach from parent to protect against vlc_object_find_name() */
parent = p_this->p_parent;
if (likely(parent))
{
/* Unlink */
- if (internals->prev != NULL)
- internals->prev->next = internals->next;
+ vlc_object_internals_t *prev = internals->prev;
+ vlc_object_internals_t *next = internals->next;
+
+ if (prev != NULL)
+ prev->next = next;
else
- vlc_internals(parent)->first = internals->next;
- if (internals->next != NULL)
- internals->next->prev = internals->prev;
+ vlc_internals (parent)->first = next;
+ if (next != NULL)
+ next->prev = prev;
}
/* We have no children */
}
libvlc_unlock (p_this->p_libvlc);
- if( b_should_destroy )
+ if (likely(refs == 1))
{
- int canc;
-
- canc = vlc_savecancel ();
+ int canc = vlc_savecancel ();
vlc_object_destroy( p_this );
vlc_restorecancel (canc);
if (parent)
}
}
-#undef vlc_object_attach
+#undef vlc_object_alive
/**
- ****************************************************************************
- * 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.
- *****************************************************************************/
-void vlc_object_attach( vlc_object_t *p_this, vlc_object_t *p_parent )
+ * This function returns true, except when it returns false.
+ * \warning Do not use this function. Ever. You were warned.
+ */
+bool vlc_object_alive(vlc_object_t *obj)
{
- if( !p_this ) return;
-
- vlc_object_internals_t *pap = vlc_internals (p_parent);
- vlc_object_internals_t *priv = vlc_internals (p_this);
-
- priv->prev = NULL;
- vlc_object_hold (p_parent);
- libvlc_lock (p_this->p_libvlc);
-
- /* Attach the parent to its child */
- assert (p_this->p_parent == NULL);
- p_this->p_parent = p_parent;
-
- /* Attach the child to its parent */
- priv->next = pap->first;
- if (priv->next != NULL)
- priv->next->prev = priv;
- pap->first = priv;
- libvlc_unlock (p_this->p_libvlc);
+ vlc_object_internals_t *internals = vlc_internals (obj);
+ return atomic_load (&internals->alive);
}
-
#undef vlc_list_children
/**
* Gets the list of children of an objects, and increment their reference
MYCASE( TIME, "time" );
MYCASE( COORDS, "coords" );
MYCASE( ADDRESS, "address" );
- MYCASE( MUTEX, "mutex" );
#undef MYCASE
}
printf( " *-o \"%s\" (%s", p_var->psz_name, psz_type );
switch( p_var->i_type & VLC_VAR_CLASS )
{
case VLC_VAR_VOID:
- case VLC_VAR_MUTEX:
break;
case VLC_VAR_BOOL:
printf( ": %s", p_var->val.b_bool ? "true" : "false" );
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;
+ (void)oldval;
vlc_object_t *p_object = NULL;
if( *newval.psz_string )
{
/* try using the object's name to find it */
- p_object = vlc_object_find_name( p_this, newval.psz_string,
- FIND_ANYWHERE );
+ p_object = vlc_object_find_name( p_data, newval.psz_string );
if( !p_object )
- {
return VLC_ENOOBJ;
- }
}
libvlc_lock (p_this->p_libvlc);
/* Following functions are local */
-static vlc_object_t *FindParentName (vlc_object_t *p_this, const char *name)
+static vlc_object_t *FindName (vlc_object_internals_t *priv, const char *name)
{
- for (vlc_object_t *parent = p_this->p_parent;
- parent != NULL;
- parent = parent->p_parent)
- {
- const char *objname = vlc_internals (parent)->psz_name;
- if (objname && !strcmp (objname, name))
- return vlc_object_hold (parent);
- }
- return NULL;
-}
+ if (priv->psz_name != NULL && !strcmp (priv->psz_name, name))
+ return vlc_object_hold (vlc_externals (priv));
-static vlc_object_t *FindChildName (vlc_object_internals_t *priv,
- const char *name)
-{
for (priv = priv->first; priv != NULL; priv = priv->next)
{
- if (priv->psz_name && !strcmp (priv->psz_name, name))
- return vlc_object_hold (vlc_externals (priv));
-
- vlc_object_t *found = FindChildName (priv, name);
+ vlc_object_t *found = FindName (priv, name);
if (found != NULL)
return found;
}
}
vlc_mutex_unlock (&name_lock);
- psz_refcount[0] = '\0';
- if( priv->i_refcount > 0 )
- snprintf( psz_refcount, 19, ", %u refs", priv->i_refcount );
+ snprintf( psz_refcount, 19, ", %u refs", atomic_load( &priv->refs ) );
psz_parent[0] = '\0';
/* FIXME: need structure lock!!! */