/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000 Wim Taymans <wtay@chello.be>
* 2005 Wim Taymans <wim@fluendo.com>
*
* gstobject.c: Fundamental class used for all of GStreamer
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:gstobject
* @short_description: Base class for the GStreamer object hierarchy
*
* #GstObject provides a root for the object hierarchy tree filed in by the
* GStreamer library. It is currently a thin wrapper on top of
* #GObject. It is an abstract class that is not very usable on its own.
*
* #GstObject gives us basic refcounting, parenting functionality and locking.
* Most of the function are just extended for special GStreamer needs and can be
* found under the same name in the base class of #GstObject which is #GObject
* (e.g. g_object_ref() becomes gst_object_ref()).
*
* The most interesting difference between #GstObject and #GObject is the
* "floating" reference count. A #GObject is created with a reference count of
* 1, owned by the creator of the #GObject. (The owner of a reference is the
* code section that has the right to call gst_object_unref() in order to
* remove that reference.) A #GstObject is created with a reference count of 1
* also, but it isn't owned by anyone; Instead, the initial reference count
* of a #GstObject is "floating". The floating reference can be removed by
* anyone at any time, by calling gst_object_sink(). gst_object_sink() does
* nothing if an object is already sunk (has no floating reference).
*
* When you add a #GstElement to its parent container, the parent container will
* do this:
* <informalexample>
* <programlisting>
* gst_object_ref (GST_OBJECT (child_element));
* gst_object_sink (GST_OBJECT (child_element));
* </programlisting>
* </informalexample>
* This means that the container now owns a reference to the child element
* (since it called gst_object_ref()), and the child element has no floating
* reference.
*
* The purpose of the floating reference is to keep the child element alive
* until you add it to a parent container, which then manages the lifetime of
* the object itself:
* <informalexample>
* <programlisting>
* element = gst_element_factory_make (factoryname, name);
* // element has one floating reference to keep it alive
* gst_bin_add (GST_BIN (bin), element);
* // element has one non-floating reference owned by the container
* </programlisting>
* </informalexample>
*
* Another effect of this is, that calling gst_object_unref() on a bin object,
* will also destoy all the #GstElement objects in it. The same is true for
* calling gst_bin_remove().
*
* Special care has to be taken for all methods that gst_object_sink() an object
* since if the caller of those functions had a floating reference to the object,
* the object reference is now invalid.
*
* In contrast to #GObject instances, #GstObject adds a name property. The functions
* gst_object_set_name() and gst_object_get_name() are used to set/get the name
* of the object.
*
* Last reviewed on 2005-11-09 (0.9.4)
*/
#include "gst_private.h"
#include "gstobject.h"
#include "gstmarshal.h"
#include "gstinfo.h"
#include "gstutils.h"
#ifdef __SYMBIAN32__
#include <glib_global.h>
#include <gobject_global.h>
#endif
#ifndef GST_DISABLE_TRACE
#include "gsttrace.h"
static GstAllocTrace *_gst_object_trace;
#endif
#define DEBUG_REFCOUNT
/* Object signals and args */
enum
{
PARENT_SET,
PARENT_UNSET,
#ifndef GST_DISABLE_LOADSAVE
OBJECT_SAVED,
#endif
DEEP_NOTIFY,
LAST_SIGNAL
};
enum
{
ARG_0,
ARG_NAME
/* FILL ME */
};
enum
{
SO_OBJECT_LOADED,
SO_LAST_SIGNAL
};
/* maps type name quark => count */
static GData *object_name_counts = NULL;
G_LOCK_DEFINE_STATIC (object_name_mutex);
typedef struct _GstSignalObject GstSignalObject;
typedef struct _GstSignalObjectClass GstSignalObjectClass;
static GType gst_signal_object_get_type (void);
static void gst_signal_object_class_init (GstSignalObjectClass * klass);
static void gst_signal_object_init (GstSignalObject * object);
#ifndef GST_DISABLE_LOADSAVE
static guint gst_signal_object_signals[SO_LAST_SIGNAL] = { 0 };
#endif
static void gst_object_class_init (GstObjectClass * klass);
static void gst_object_init (GTypeInstance * instance, gpointer g_class);
static void gst_object_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_object_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static void gst_object_dispatch_properties_changed (GObject * object,
guint n_pspecs, GParamSpec ** pspecs);
static void gst_object_dispose (GObject * object);
static void gst_object_finalize (GObject * object);
static gboolean gst_object_set_name_default (GstObject * object);
#ifndef GST_DISABLE_LOADSAVE
static void gst_object_real_restore_thyself (GstObject * object,
xmlNodePtr self);
#endif
static GObjectClass *parent_class = NULL;
static guint gst_object_signals[LAST_SIGNAL] = { 0 };
#ifdef __SYMBIAN32__
EXPORT_C
#endif
GType
gst_object_get_type (void)
{
static GType gst_object_type = 0;
if (G_UNLIKELY (gst_object_type == 0)) {
static const GTypeInfo object_info = {
sizeof (GstObjectClass),
NULL,
NULL,
(GClassInitFunc) gst_object_class_init,
NULL,
NULL,
sizeof (GstObject),
0,
gst_object_init,
NULL
};
gst_object_type =
g_type_register_static (G_TYPE_OBJECT, "GstObject", &object_info,
G_TYPE_FLAG_ABSTRACT);
}
return gst_object_type;
}
static void
gst_object_class_init (GstObjectClass * klass)
{
GObjectClass *gobject_class;
gobject_class = G_OBJECT_CLASS (klass);
parent_class = g_type_class_peek_parent (klass);
#ifndef GST_DISABLE_TRACE
_gst_object_trace = gst_alloc_trace_register (g_type_name (GST_TYPE_OBJECT));
#endif
gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_object_set_property);
gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_object_get_property);
g_object_class_install_property (gobject_class, ARG_NAME,
g_param_spec_string ("name", "Name", "The name of the object",
NULL, G_PARAM_READWRITE | G_PARAM_CONSTRUCT));
/**
* GstObject::parent-set:
* @gstobject: a #GstObject
* @parent: the new parent
*
* Emitted when the parent of an object is set.
*/
gst_object_signals[PARENT_SET] =
g_signal_new ("parent-set", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstObjectClass, parent_set), NULL, NULL,
g_cclosure_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_OBJECT);
/**
* GstObject::parent-unset:
* @gstobject: a #GstObject
* @parent: the old parent
*
* Emitted when the parent of an object is unset.
*/
gst_object_signals[PARENT_UNSET] =
g_signal_new ("parent-unset", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstObjectClass, parent_unset), NULL,
NULL, g_cclosure_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_OBJECT);
#ifndef GST_DISABLE_LOADSAVE
/**
* GstObject::object-saved:
* @gstobject: a #GstObject
* @xml_node: the xmlNodePtr of the parent node
*
* Trigered whenever a new object is saved to XML. You can connect to this
* signal to insert custom XML tags into the core XML.
*/
/* FIXME This should be the GType of xmlNodePtr instead of G_TYPE_POINTER
* (if libxml would use GObject)
*/
gst_object_signals[OBJECT_SAVED] =
g_signal_new ("object-saved", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstObjectClass, object_saved), NULL,
NULL, g_cclosure_marshal_VOID__POINTER, G_TYPE_NONE, 1, G_TYPE_POINTER);
klass->restore_thyself = gst_object_real_restore_thyself;
#endif
/**
* GstObject::deep-notify:
* @gstobject: a #GstObject
* @prop_object: the object that originated the signal
* @prop: the property that changed
*
* The deep notify signal is used to be notified of property changes. It is
* typically attached to the toplevel bin to receive notifications from all
* the elements contained in that bin.
*/
gst_object_signals[DEEP_NOTIFY] =
g_signal_new ("deep-notify", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_FIRST | G_SIGNAL_NO_RECURSE | G_SIGNAL_DETAILED |
G_SIGNAL_NO_HOOKS, G_STRUCT_OFFSET (GstObjectClass, deep_notify), NULL,
NULL, gst_marshal_VOID__OBJECT_PARAM, G_TYPE_NONE, 2, GST_TYPE_OBJECT,
G_TYPE_PARAM);
klass->path_string_separator = "/";
klass->lock = g_new0 (GStaticRecMutex, 1);
g_static_rec_mutex_init (klass->lock);
klass->signal_object = g_object_new (gst_signal_object_get_type (), NULL);
/* see the comments at gst_object_dispatch_properties_changed */
gobject_class->dispatch_properties_changed
= GST_DEBUG_FUNCPTR (gst_object_dispatch_properties_changed);
gobject_class->dispose = gst_object_dispose;
gobject_class->finalize = gst_object_finalize;
}
static void
gst_object_init (GTypeInstance * instance, gpointer g_class)
{
GstObject *object = GST_OBJECT (instance);
object->lock = g_mutex_new ();
object->parent = NULL;
object->name = NULL;
GST_CAT_LOG_OBJECT (GST_CAT_REFCOUNTING, object, "%p new", object);
#ifndef GST_DISABLE_TRACE
gst_alloc_trace_new (_gst_object_trace, object);
#endif
object->flags = 0;
GST_OBJECT_FLAG_SET (object, GST_OBJECT_FLOATING);
}
/**
* gst_object_ref:
* @object: a #GstObject to reference
*
* Increments the reference count on @object. This function
* does not take the lock on @object because it relies on
* atomic refcounting.
*
* This object returns the input parameter to ease writing
* constructs like :
* result = gst_object_ref (object->parent);
*
* Returns: A pointer to @object
*/
#ifdef __SYMBIAN32__
EXPORT_C
#endif
gpointer
gst_object_ref (gpointer object)
{
g_return_val_if_fail (object != NULL, NULL);
#ifdef DEBUG_REFCOUNT
GST_CAT_LOG_OBJECT (GST_CAT_REFCOUNTING, object, "%p ref %d->%d",
object,
((GObject *) object)->ref_count, ((GObject *) object)->ref_count + 1);
#endif
g_object_ref (object);
return object;
}
/**
* gst_object_unref:
* @object: a #GstObject to unreference
*
* Decrements the reference count on @object. If reference count hits
* zero, destroy @object. This function does not take the lock
* on @object as it relies on atomic refcounting.
*
* The unref method should never be called with the LOCK held since
* this might deadlock the dispose function.
*/
#ifdef __SYMBIAN32__
EXPORT_C
#endif
void
gst_object_unref (gpointer object)
{
g_return_if_fail (object != NULL);
g_return_if_fail (((GObject *) object)->ref_count > 0);
#ifdef DEBUG_REFCOUNT
GST_CAT_LOG_OBJECT (GST_CAT_REFCOUNTING, object, "%p unref %d->%d",
object,
((GObject *) object)->ref_count, ((GObject *) object)->ref_count - 1);
#endif
g_object_unref (object);
}
/**
* gst_object_sink:
* @object: a #GstObject to sink
*
* If @object was floating, the #GST_OBJECT_FLOATING flag is removed
* and @object is unreffed. When @object was not floating,
* this function does nothing.
*
* Any newly created object has a refcount of 1 and is floating.
* This function should be used when creating a new object to
* symbolically 'take ownership' of @object. This done by first doing a
* gst_object_ref() to keep a reference to @object and then gst_object_sink()
* to remove and unref any floating references to @object.
* Use gst_object_set_parent() to have this done for you.
*
* MT safe. This function grabs and releases @object lock.
*/
#ifdef __SYMBIAN32__
EXPORT_C
#endif
void
gst_object_sink (gpointer object)
{
g_return_if_fail (GST_IS_OBJECT (object));
GST_CAT_LOG_OBJECT (GST_CAT_REFCOUNTING, object, "sink");
GST_OBJECT_LOCK (object);
if (G_LIKELY (GST_OBJECT_IS_FLOATING (object))) {
GST_CAT_LOG_OBJECT (GST_CAT_REFCOUNTING, object, "clear floating flag");
GST_OBJECT_FLAG_UNSET (object, GST_OBJECT_FLOATING);
GST_OBJECT_UNLOCK (object);
gst_object_unref (object);
} else {
GST_OBJECT_UNLOCK (object);
}
}
/**
* gst_object_replace:
* @oldobj: pointer to a place of a #GstObject to replace
* @newobj: a new #GstObject
*
* Unrefs the #GstObject pointed to by @oldobj, refs @newobj and
* puts @newobj in *@oldobj. Be carefull when calling this
* function, it does not take any locks. You might want to lock
* the object owning @oldobj pointer before calling this
* function.
*
* Make sure not to LOCK @oldobj because it might be unreffed
* which could cause a deadlock when it is disposed.
*/
#ifdef __SYMBIAN32__
EXPORT_C
#endif
void
gst_object_replace (GstObject ** oldobj, GstObject * newobj)
{
g_return_if_fail (oldobj != NULL);
g_return_if_fail (*oldobj == NULL || GST_IS_OBJECT (*oldobj));
g_return_if_fail (newobj == NULL || GST_IS_OBJECT (newobj));
#ifdef DEBUG_REFCOUNT
GST_CAT_LOG (GST_CAT_REFCOUNTING, "replace %s (%d) with %s (%d)",
*oldobj ? GST_STR_NULL (GST_OBJECT_NAME (*oldobj)) : "(NONE)",
*oldobj ? G_OBJECT (*oldobj)->ref_count : 0,
newobj ? GST_STR_NULL (GST_OBJECT_NAME (newobj)) : "(NONE)",
newobj ? G_OBJECT (newobj)->ref_count : 0);
#endif
if (G_LIKELY (*oldobj != newobj)) {
if (newobj)
gst_object_ref (newobj);
if (*oldobj)
gst_object_unref (*oldobj);
*oldobj = newobj;
}
}
/* dispose is called when the object has to release all links
* to other objects */
static void
gst_object_dispose (GObject * object)
{
GstObject *parent;
GST_CAT_LOG_OBJECT (GST_CAT_REFCOUNTING, object, "dispose");
GST_OBJECT_LOCK (object);
if ((parent = GST_OBJECT_PARENT (object)))
goto have_parent;
GST_OBJECT_PARENT (object) = NULL;
GST_OBJECT_UNLOCK (object);
parent_class->dispose (object);
return;
/* ERRORS */
have_parent:
{
g_critical ("\nTrying to dispose object \"%s\", but it still has a "
"parent \"%s\".\nYou need to let the parent manage the "
"object instead of unreffing the object directly.\n",
GST_OBJECT_NAME (object), GST_OBJECT_NAME (parent));
GST_OBJECT_UNLOCK (object);
/* ref the object again to revive it in this error case */
object = gst_object_ref (object);
return;
}
}
/* finalize is called when the object has to free its resources */
static void
gst_object_finalize (GObject * object)
{
GstObject *gstobject = GST_OBJECT (object);
GST_CAT_LOG_OBJECT (GST_CAT_REFCOUNTING, object, "finalize");
g_signal_handlers_destroy (object);
g_free (gstobject->name);
g_mutex_free (gstobject->lock);
#ifndef GST_DISABLE_TRACE
gst_alloc_trace_free (_gst_object_trace, object);
#endif
parent_class->finalize (object);
}
/* Changing a GObject property of a GstObject will result in "deep_notify"
* signals being emitted by the object itself, as well as in each parent
* object. This is so that an application can connect a listener to the
* top-level bin to catch property-change notifications for all contained
* elements.
*
* This function is not MT safe in glib < 2.8 so we need to lock it with a
* classwide mutex in that case.
*
* MT safe.
*/
static void
gst_object_dispatch_properties_changed (GObject * object,
guint n_pspecs, GParamSpec ** pspecs)
{
GstObject *gst_object, *parent, *old_parent;
guint i;
gchar *name, *debug_name;
GstObjectClass *klass;
/* we fail when this is not a GstObject */
g_return_if_fail (GST_IS_OBJECT (object));
klass = GST_OBJECT_GET_CLASS (object);
/* do the standard dispatching */
G_OBJECT_CLASS (parent_class)->dispatch_properties_changed (object, n_pspecs,
pspecs);
gst_object = GST_OBJECT_CAST (object);
name = gst_object_get_name (gst_object);
debug_name = GST_STR_NULL (name);
/* now let the parent dispatch those, too */
parent = gst_object_get_parent (gst_object);
while (parent) {
for (i = 0; i < n_pspecs; i++) {
GST_LOG_OBJECT (parent, "deep notification from %s (%s)",
debug_name, pspecs[i]->name);
g_signal_emit (parent, gst_object_signals[DEEP_NOTIFY],
g_quark_from_string (pspecs[i]->name), GST_OBJECT_CAST (object),
pspecs[i]);
}
old_parent = parent;
parent = gst_object_get_parent (old_parent);
gst_object_unref (old_parent);
}
g_free (name);
}
/**
* gst_object_default_deep_notify:
* @object: the #GObject that signalled the notify.
* @orig: a #GstObject that initiated the notify.
* @pspec: a #GParamSpec of the property.
* @excluded_props: a set of user-specified properties to exclude or
* NULL to show all changes.
*
* A default deep_notify signal callback for an object. The user data
* should contain a pointer to an array of strings that should be excluded
* from the notify. The default handler will print the new value of the property
* using g_print.
*
* MT safe. This function grabs and releases @object's LOCK for getting its
* path string.
*/
#ifdef __SYMBIAN32__
EXPORT_C
#endif
void
gst_object_default_deep_notify (GObject * object, GstObject * orig,
GParamSpec * pspec, gchar ** excluded_props)
{
GValue value = { 0, }; /* the important thing is that value.type = 0 */
gchar *str = NULL;
gchar *name = NULL;
if (pspec->flags & G_PARAM_READABLE) {
/* let's not print these out for excluded properties... */
while (excluded_props != NULL && *excluded_props != NULL) {
if (strcmp (pspec->name, *excluded_props) == 0)
return;
excluded_props++;
}
g_value_init (&value, G_PARAM_SPEC_VALUE_TYPE (pspec));
g_object_get_property (G_OBJECT (orig), pspec->name, &value);
if (G_IS_PARAM_SPEC_ENUM (pspec)) {
GEnumValue *enum_value;
enum_value =
g_enum_get_value (G_ENUM_CLASS (g_type_class_ref (pspec->value_type)),
g_value_get_enum (&value));
str = g_strdup_printf ("%s (%d)", enum_value->value_nick,
enum_value->value);
} else {
str = g_strdup_value_contents (&value);
}
name = gst_object_get_path_string (orig);
g_print ("%s: %s = %s\n", name, pspec->name, str);
g_free (name);
g_free (str);
g_value_unset (&value);
} else {
name = gst_object_get_path_string (orig);
g_warning ("Parameter %s not readable in %s.", pspec->name, name);
g_free (name);
}
}
static gboolean
gst_object_set_name_default (GstObject * object)
{
const gchar *type_name;
gint count;
gchar *name, *tmp;
gboolean result;
GQuark q;
/* to ensure guaranteed uniqueness across threads, only one thread
* may ever assign a name */
G_LOCK (object_name_mutex);
if (!object_name_counts) {
g_datalist_init (&object_name_counts);
}
q = g_type_qname (G_OBJECT_TYPE (object));
count = GPOINTER_TO_INT (g_datalist_id_get_data (&object_name_counts, q));
g_datalist_id_set_data (&object_name_counts, q, GINT_TO_POINTER (count + 1));
G_UNLOCK (object_name_mutex);
/* GstFooSink -> foosinkN */
type_name = g_quark_to_string (q);
if (strncmp (type_name, "Gst", 3) == 0)
type_name += 3;
tmp = g_strdup_printf ("%s%d", type_name, count);
name = g_ascii_strdown (tmp, strlen (tmp));
g_free (tmp);
result = gst_object_set_name (object, name);
g_free (name);
return result;
}
/**
* gst_object_set_name:
* @object: a #GstObject
* @name: new name of object
*
* Sets the name of @object, or gives @object a guaranteed unique
* name (if @name is NULL).
* This function makes a copy of the provided name, so the caller
* retains ownership of the name it sent.
*
* Returns: TRUE if the name could be set. Since Objects that have
* a parent cannot be renamed, this function returns FALSE in those
* cases.
*
* MT safe. This function grabs and releases @object's LOCK.
*/
#ifdef __SYMBIAN32__
EXPORT_C
#endif
gboolean
gst_object_set_name (GstObject * object, const gchar * name)
{
gboolean result;
g_return_val_if_fail (GST_IS_OBJECT (object), FALSE);
GST_OBJECT_LOCK (object);
/* parented objects cannot be renamed */
if (G_UNLIKELY (object->parent != NULL))
goto had_parent;
if (name != NULL) {
g_free (object->name);
object->name = g_strdup (name);
GST_OBJECT_UNLOCK (object);
result = TRUE;
} else {
GST_OBJECT_UNLOCK (object);
result = gst_object_set_name_default (object);
}
return result;
/* error */
had_parent:
{
GST_WARNING ("parented objects can't be renamed");
GST_OBJECT_UNLOCK (object);
return FALSE;
}
}
/**
* gst_object_get_name:
* @object: a #GstObject
*
* Returns a copy of the name of @object.
* Caller should g_free() the return value after usage.
* For a nameless object, this returns NULL, which you can safely g_free()
* as well.
*
* Returns: the name of @object. g_free() after usage.
*
* MT safe. This function grabs and releases @object's LOCK.
*/
#ifdef __SYMBIAN32__
EXPORT_C
#endif
gchar *
gst_object_get_name (GstObject * object)
{
gchar *result = NULL;
g_return_val_if_fail (GST_IS_OBJECT (object), NULL);
GST_OBJECT_LOCK (object);
result = g_strdup (object->name);
GST_OBJECT_UNLOCK (object);
return result;
}
/**
* gst_object_set_name_prefix:
* @object: a #GstObject
* @name_prefix: new name prefix of @object
*
* Sets the name prefix of @object to @name_prefix.
* This function makes a copy of the provided name prefix, so the caller
* retains ownership of the name prefix it sent.
*
* MT safe. This function grabs and releases @object's LOCK.
*/
#ifdef __SYMBIAN32__
EXPORT_C
#endif
void
gst_object_set_name_prefix (GstObject * object, const gchar * name_prefix)
{
g_return_if_fail (GST_IS_OBJECT (object));
GST_OBJECT_LOCK (object);
g_free (object->name_prefix);
object->name_prefix = g_strdup (name_prefix); /* NULL gives NULL */
GST_OBJECT_UNLOCK (object);
}
/**
* gst_object_get_name_prefix:
* @object: a #GstObject
*
* Returns a copy of the name prefix of @object.
* Caller should g_free() the return value after usage.
* For a prefixless object, this returns NULL, which you can safely g_free()
* as well.
*
* Returns: the name prefix of @object. g_free() after usage.
*
* MT safe. This function grabs and releases @object's LOCK.
*/
#ifdef __SYMBIAN32__
EXPORT_C
#endif
gchar *
gst_object_get_name_prefix (GstObject * object)
{
gchar *result = NULL;
g_return_val_if_fail (GST_IS_OBJECT (object), NULL);
GST_OBJECT_LOCK (object);
result = g_strdup (object->name_prefix);
GST_OBJECT_UNLOCK (object);
return result;
}
/**
* gst_object_set_parent:
* @object: a #GstObject
* @parent: new parent of object
*
* Sets the parent of @object to @parent. The object's reference count will
* be incremented, and any floating reference will be removed (see gst_object_sink()).
*
* This function causes the parent-set signal to be emitted when the parent
* was successfully set.
*
* Returns: TRUE if @parent could be set or FALSE when @object
* already had a parent or @object and @parent are the same.
*
* MT safe. Grabs and releases @object's LOCK.
*/
#ifdef __SYMBIAN32__
EXPORT_C
#endif
gboolean
gst_object_set_parent (GstObject * object, GstObject * parent)
{
g_return_val_if_fail (GST_IS_OBJECT (object), FALSE);
g_return_val_if_fail (GST_IS_OBJECT (parent), FALSE);
g_return_val_if_fail (object != parent, FALSE);
GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, object,
"set parent (ref and sink)");
GST_OBJECT_LOCK (object);
if (G_UNLIKELY (object->parent != NULL))
goto had_parent;
/* sink object, we don't call our own function because we don't
* need to release/acquire the lock needlessly or touch the refcount
* in the floating case. */
object->parent = parent;
if (G_LIKELY (GST_OBJECT_IS_FLOATING (object))) {
GST_CAT_LOG_OBJECT (GST_CAT_REFCOUNTING, object, "unsetting floating flag");
GST_OBJECT_FLAG_UNSET (object, GST_OBJECT_FLOATING);
GST_OBJECT_UNLOCK (object);
} else {
GST_OBJECT_UNLOCK (object);
gst_object_ref (object);
}
g_signal_emit (G_OBJECT (object), gst_object_signals[PARENT_SET], 0, parent);
return TRUE;
/* ERROR handling */
had_parent:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, object,
"set parent failed, object already had a parent");
GST_OBJECT_UNLOCK (object);
return FALSE;
}
}
/**
* gst_object_get_parent:
* @object: a #GstObject
*
* Returns the parent of @object. This function increases the refcount
* of the parent object so you should gst_object_unref() it after usage.
*
* Returns: parent of @object, this can be NULL if @object has no
* parent. unref after usage.
*
* MT safe. Grabs and releases @object's LOCK.
*/
#ifdef __SYMBIAN32__
EXPORT_C
#endif
GstObject *
gst_object_get_parent (GstObject * object)
{
GstObject *result = NULL;
g_return_val_if_fail (GST_IS_OBJECT (object), NULL);
GST_OBJECT_LOCK (object);
result = object->parent;
if (G_LIKELY (result))
gst_object_ref (result);
GST_OBJECT_UNLOCK (object);
return result;
}
/**
* gst_object_unparent:
* @object: a #GstObject to unparent
*
* Clear the parent of @object, removing the associated reference.
* This function decreases the refcount of @object.
*
* MT safe. Grabs and releases @object's lock.
*/
#ifdef __SYMBIAN32__
EXPORT_C
#endif
void
gst_object_unparent (GstObject * object)
{
GstObject *parent;
g_return_if_fail (GST_IS_OBJECT (object));
GST_OBJECT_LOCK (object);
parent = object->parent;
if (G_LIKELY (parent != NULL)) {
GST_CAT_LOG_OBJECT (GST_CAT_REFCOUNTING, object, "unparent");
object->parent = NULL;
GST_OBJECT_UNLOCK (object);
g_signal_emit (G_OBJECT (object), gst_object_signals[PARENT_UNSET], 0,
parent);
gst_object_unref (object);
} else {
GST_OBJECT_UNLOCK (object);
}
}
/**
* gst_object_has_ancestor:
* @object: a #GstObject to check
* @ancestor: a #GstObject to check as ancestor
*
* Check if @object has an ancestor @ancestor somewhere up in
* the hierarchy.
*
* Returns: TRUE if @ancestor is an ancestor of @object.
*
* MT safe. Grabs and releases @object's locks.
*/
#ifdef __SYMBIAN32__
EXPORT_C
#endif
gboolean
gst_object_has_ancestor (GstObject * object, GstObject * ancestor)
{
GstObject *parent;
gboolean result = FALSE;
if (object == NULL)
return FALSE;
if (object == ancestor)
return TRUE;
parent = gst_object_get_parent (object);
result = gst_object_has_ancestor (parent, ancestor);
if (parent)
gst_object_unref (parent);
return result;
}
/**
* gst_object_check_uniqueness:
* @list: a list of #GstObject to check through
* @name: the name to search for
*
* Checks to see if there is any object named @name in @list. This function
* does not do any locking of any kind. You might want to protect the
* provided list with the lock of the owner of the list. This function
* will lock each #GstObject in the list to compare the name, so be
* carefull when passing a list with a locked object.
*
* Returns: TRUE if a #GstObject named @name does not appear in @list,
* FALSE if it does.
*
* MT safe. Grabs and releases the LOCK of each object in the list.
*/
#ifdef __SYMBIAN32__
EXPORT_C
#endif
gboolean
gst_object_check_uniqueness (GList * list, const gchar * name)
{
gboolean result = TRUE;
g_return_val_if_fail (name != NULL, FALSE);
for (; list; list = g_list_next (list)) {
GstObject *child;
gboolean eq;
child = GST_OBJECT (list->data);
GST_OBJECT_LOCK (child);
eq = strcmp (GST_OBJECT_NAME (child), name) == 0;
GST_OBJECT_UNLOCK (child);
if (G_UNLIKELY (eq)) {
result = FALSE;
break;
}
}
return result;
}
#ifndef GST_DISABLE_LOADSAVE
/**
* gst_object_save_thyself:
* @object: a #GstObject to save
* @parent: The parent XML node to save @object into
*
* Saves @object into the parent XML node.
*
* Returns: the new xmlNodePtr with the saved object
*/
xmlNodePtr
gst_object_save_thyself (GstObject * object, xmlNodePtr parent)
{
GstObjectClass *oclass;
g_return_val_if_fail (GST_IS_OBJECT (object), parent);
g_return_val_if_fail (parent != NULL, parent);
oclass = GST_OBJECT_GET_CLASS (object);
if (oclass->save_thyself)
oclass->save_thyself (object, parent);
g_signal_emit (G_OBJECT (object), gst_object_signals[OBJECT_SAVED], 0,
parent);
return parent;
}
/**
* gst_object_restore_thyself:
* @object: a #GstObject to load into
* @self: The XML node to load @object from
*
* Restores @object with the data from the parent XML node.
*/
void
gst_object_restore_thyself (GstObject * object, xmlNodePtr self)
{
GstObjectClass *oclass;
g_return_if_fail (GST_IS_OBJECT (object));
g_return_if_fail (self != NULL);
oclass = GST_OBJECT_GET_CLASS (object);
if (oclass->restore_thyself)
oclass->restore_thyself (object, self);
}
static void
gst_object_real_restore_thyself (GstObject * object, xmlNodePtr self)
{
g_return_if_fail (GST_IS_OBJECT (object));
g_return_if_fail (self != NULL);
gst_class_signal_emit_by_name (object, "object_loaded", self);
}
#endif /* GST_DISABLE_LOADSAVE */
static void
gst_object_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstObject *gstobject;
gstobject = GST_OBJECT (object);
switch (prop_id) {
case ARG_NAME:
gst_object_set_name (gstobject, g_value_get_string (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_object_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstObject *gstobject;
gstobject = GST_OBJECT (object);
switch (prop_id) {
case ARG_NAME:
g_value_take_string (value, gst_object_get_name (gstobject));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
/**
* gst_object_get_path_string:
* @object: a #GstObject
*
* Generates a string describing the path of @object in
* the object hierarchy. Only useful (or used) for debugging.
*
* Returns: a string describing the path of @object. You must
* g_free() the string after usage.
*
* MT safe. Grabs and releases the #GstObject's LOCK for all objects
* in the hierarchy.
*/
#ifdef __SYMBIAN32__
EXPORT_C
#endif
gchar *
gst_object_get_path_string (GstObject * object)
{
GSList *parentage;
GSList *parents;
void *parent;
gchar *prevpath, *path;
gchar *component;
gchar *separator;
/* ref object before adding to list */
gst_object_ref (object);
parentage = g_slist_prepend (NULL, object);
path = g_strdup ("");
/* first walk the object hierarchy to build a list of the parents,
* be carefull here with refcounting. */
do {
if (GST_IS_OBJECT (object)) {
parent = gst_object_get_parent (object);
/* add parents to list, refcount remains increased while
* we handle the object */
if (parent)
parentage = g_slist_prepend (parentage, parent);
} else {
break;
}
object = parent;
} while (object != NULL);
/* then walk the parent list and print them out. we need to
* decrease the refcounting on each element after we handled
* it. */
for (parents = parentage; parents; parents = g_slist_next (parents)) {
if (GST_IS_OBJECT (parents->data)) {
GstObject *item = GST_OBJECT_CAST (parents->data);
GstObjectClass *oclass = GST_OBJECT_GET_CLASS (item);
component = gst_object_get_name (item);
separator = oclass->path_string_separator;
/* and unref now */
gst_object_unref (item);
} else {
component = g_strdup_printf ("%p", parents->data);
separator = "/";
}
prevpath = path;
path = g_strjoin (separator, prevpath, component, NULL);
g_free (prevpath);
g_free (component);
}
g_slist_free (parentage);
return path;
}
struct _GstSignalObject
{
GObject object;
};
struct _GstSignalObjectClass
{
GObjectClass parent_class;
/* signals */
#ifndef GST_DISABLE_LOADSAVE
void (*object_loaded) (GstSignalObject * object, GstObject * new,
xmlNodePtr self);
#endif
};
static GType
gst_signal_object_get_type (void)
{
static GType signal_object_type = 0;
if (G_UNLIKELY (signal_object_type == 0)) {
static const GTypeInfo signal_object_info = {
sizeof (GstSignalObjectClass),
NULL,
NULL,
(GClassInitFunc) gst_signal_object_class_init,
NULL,
NULL,
sizeof (GstSignalObject),
0,
(GInstanceInitFunc) gst_signal_object_init,
NULL
};
signal_object_type =
g_type_register_static (G_TYPE_OBJECT, "GstSignalObject",
&signal_object_info, 0);
}
return signal_object_type;
}
static void
gst_signal_object_class_init (GstSignalObjectClass * klass)
{
GObjectClass *gobject_class;
gobject_class = (GObjectClass *) klass;
parent_class = g_type_class_peek_parent (klass);
#ifndef GST_DISABLE_LOADSAVE
gst_signal_object_signals[SO_OBJECT_LOADED] =
g_signal_new ("object-loaded", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstSignalObjectClass, object_loaded),
NULL, NULL, gst_marshal_VOID__OBJECT_POINTER, G_TYPE_NONE, 2,
G_TYPE_OBJECT, G_TYPE_POINTER);
#endif
}
static void
gst_signal_object_init (GstSignalObject * object)
{
}
/**
* gst_class_signal_connect
* @klass: a #GstObjectClass to attach the signal to
* @name: the name of the signal to attach to
* @func: the signal function
* @func_data: a pointer to user data
*
* Connect to a class signal.
*
* Returns: the signal id.
*/
#ifdef __SYMBIAN32__
EXPORT_C
#endif
guint
gst_class_signal_connect (GstObjectClass * klass,
const gchar * name, gpointer func, gpointer func_data)
{
/* [0.11] func parameter needs to be changed to a GCallback *
* doing so now would be an API break. */
return g_signal_connect (klass->signal_object, name, G_CALLBACK (func),
func_data);
}
#ifndef GST_DISABLE_LOADSAVE
/**
* gst_class_signal_emit_by_name:
* @object: a #GstObject that emits the signal
* @name: the name of the signal to emit
* @self: data for the signal
*
* emits the named class signal.
*/
void
gst_class_signal_emit_by_name (GstObject * object,
const gchar * name, xmlNodePtr self)
{
GstObjectClass *oclass;
oclass = GST_OBJECT_GET_CLASS (object);
g_signal_emit_by_name (oclass->signal_object, name, object, self);
}
#endif /* GST_DISABLE_LOADSAVE */