/* GStreamer * Copyright (C) 1999,2000 Erik Walthinsen * 2004 Wim Taymans * * gstelement.c: The base element, all elements derive from this * * 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. */ #include "gst_private.h" #include #include #include #include "gstelement.h" #include "gstbus.h" #include "gstmarshal.h" #include "gsterror.h" #include "gstevent.h" #include "gstutils.h" #include "gstinfo.h" #include "gst-i18n-lib.h" /* Element signals and args */ enum { STATE_CHANGE, NEW_PAD, PAD_REMOVED, NO_MORE_PADS, /* add more above */ LAST_SIGNAL }; enum { ARG_0 /* FILL ME */ }; extern void __gst_element_details_clear (GstElementDetails * dp); extern void __gst_element_details_copy (GstElementDetails * dest, const GstElementDetails * src); static void gst_element_class_init (GstElementClass * klass); static void gst_element_init (GstElement * element); static void gst_element_base_class_init (gpointer g_class); static void gst_element_base_class_finalize (gpointer g_class); static void gst_element_dispose (GObject * object); static void gst_element_finalize (GObject * object); static GstStateChangeReturn gst_element_change_state (GstElement * element, GstStateChange transition); static GstStateChangeReturn gst_element_get_state_func (GstElement * element, GstState * state, GstState * pending, GTimeVal * timeout); static void gst_element_set_bus_func (GstElement * element, GstBus * bus); #ifndef GST_DISABLE_LOADSAVE static xmlNodePtr gst_element_save_thyself (GstObject * object, xmlNodePtr parent); static void gst_element_restore_thyself (GstObject * parent, xmlNodePtr self); #endif GType _gst_element_type = 0; static GstObjectClass *parent_class = NULL; static guint gst_element_signals[LAST_SIGNAL] = { 0 }; GType gst_element_get_type (void) { if (!_gst_element_type) { static const GTypeInfo element_info = { sizeof (GstElementClass), gst_element_base_class_init, gst_element_base_class_finalize, (GClassInitFunc) gst_element_class_init, NULL, NULL, sizeof (GstElement), 0, (GInstanceInitFunc) gst_element_init, NULL }; _gst_element_type = g_type_register_static (GST_TYPE_OBJECT, "GstElement", &element_info, G_TYPE_FLAG_ABSTRACT); } return _gst_element_type; } static void gst_element_class_init (GstElementClass * klass) { GObjectClass *gobject_class; GstObjectClass *gstobject_class; gobject_class = (GObjectClass *) klass; gstobject_class = (GstObjectClass *) klass; parent_class = g_type_class_ref (GST_TYPE_OBJECT); /** * GstElement::state-changed: * @gstelement: the object which received the signal * @old_state: the GST_STATE_XXX before the change * @new_state: the GST_STATE_XXX after the change * * the #GstState of the element has been changed */ gst_element_signals[STATE_CHANGE] = g_signal_new ("state-changed", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstElementClass, state_changed), NULL, NULL, gst_marshal_VOID__INT_INT, G_TYPE_NONE, 2, G_TYPE_INT, G_TYPE_INT); /** * GstElement::pad-added: * @gstelement: the object which received the signal * @new_pad: the pad that has been added * * a new #GstPad has been added to the element */ gst_element_signals[NEW_PAD] = g_signal_new ("pad-added", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstElementClass, pad_added), NULL, NULL, gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, G_TYPE_OBJECT); /** * GstElement::pad-removed: * @gstelement: the object which received the signal * @old_pad: the pad that has been removed * * a #GstPad has been removed from the element */ gst_element_signals[PAD_REMOVED] = g_signal_new ("pad-removed", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstElementClass, pad_removed), NULL, NULL, gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, G_TYPE_OBJECT); /** * GstElement::no-more-pads: * @gstelement: the object which received the signal * * This signals that the element will not generate more dynamic pads. */ gst_element_signals[NO_MORE_PADS] = g_signal_new ("no-more-pads", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstElementClass, no_more_pads), NULL, NULL, gst_marshal_VOID__VOID, G_TYPE_NONE, 0); gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_element_dispose); gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_element_finalize); #ifndef GST_DISABLE_LOADSAVE gstobject_class->save_thyself = GST_DEBUG_FUNCPTR (gst_element_save_thyself); gstobject_class->restore_thyself = GST_DEBUG_FUNCPTR (gst_element_restore_thyself); #endif klass->change_state = GST_DEBUG_FUNCPTR (gst_element_change_state); klass->get_state = GST_DEBUG_FUNCPTR (gst_element_get_state_func); klass->set_bus = GST_DEBUG_FUNCPTR (gst_element_set_bus_func); klass->numpadtemplates = 0; klass->elementfactory = NULL; } static void gst_element_base_class_init (gpointer g_class) { GstElementClass *element_class = GST_ELEMENT_CLASS (g_class); memset (&element_class->details, 0, sizeof (GstElementDetails)); element_class->padtemplates = NULL; } static void gst_element_base_class_finalize (gpointer g_class) { GstElementClass *klass = GST_ELEMENT_CLASS (g_class); g_list_foreach (klass->padtemplates, (GFunc) gst_object_unref, NULL); g_list_free (klass->padtemplates); __gst_element_details_clear (&klass->details); } static void gst_element_init (GstElement * element) { element->current_state = GST_STATE_NULL; element->pending_state = GST_STATE_VOID_PENDING; element->state_lock = g_mutex_new (); element->state_cond = g_cond_new (); } /** * gst_element_default_error: * @object: a #GObject that signalled the error. * @orig: the #GstObject that initiated the error. * @error: the GError. * @debug: an additional debug information string, or NULL. * * A default error signal callback to attach to an element. * The user data passed to the g_signal_connect is ignored. * * The default handler will simply print the error string using g_print. * * MT safe. */ void gst_element_default_error (GObject * object, GstObject * source, GError * error, gchar * debug) { gchar *name = gst_object_get_path_string (source); g_print (_("ERROR: from element %s: %s\n"), name, error->message); if (debug) g_print (_("Additional debug info:\n%s\n"), debug); g_free (name); } /** * gst_element_release_request_pad: * @element: a #GstElement to release the request pad of. * @pad: the #GstPad to release. * * Makes the element free the previously requested pad as obtained * with gst_element_get_request_pad(). * * MT safe. */ void gst_element_release_request_pad (GstElement * element, GstPad * pad) { GstElementClass *oclass; g_return_if_fail (GST_IS_ELEMENT (element)); g_return_if_fail (GST_IS_PAD (pad)); oclass = GST_ELEMENT_GET_CLASS (element); if (oclass->release_pad) (oclass->release_pad) (element, pad); else gst_element_remove_pad (element, pad); } /** * gst_element_requires_clock: * @element: a #GstElement to query * * Query if the element requires a clock. * * Returns: TRUE if the element requires a clock * * MT safe. */ gboolean gst_element_requires_clock (GstElement * element) { gboolean result = FALSE; g_return_val_if_fail (GST_IS_ELEMENT (element), result); result = (GST_ELEMENT_GET_CLASS (element)->set_clock != NULL); return result; } /** * gst_element_provides_clock: * @element: a #GstElement to query * * Query if the element provides a clock. * * Returns: TRUE if the element provides a clock * * MT safe. */ gboolean gst_element_provides_clock (GstElement * element) { gboolean result = FALSE; g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE); result = (GST_ELEMENT_GET_CLASS (element)->get_clock != NULL); return result; } /** * gst_element_set_clock: * @element: a #GstElement to set the clock for. * @clock: the #GstClock to set for the element. * * Sets the clock for the element. This function increases the * refcount on the clock. Any previously set clock on the object * is unreffed. * * MT safe. */ void gst_element_set_clock (GstElement * element, GstClock * clock) { GstElementClass *oclass; g_return_if_fail (GST_IS_ELEMENT (element)); oclass = GST_ELEMENT_GET_CLASS (element); if (oclass->set_clock) oclass->set_clock (element, clock); GST_LOCK (element); gst_object_replace ((GstObject **) & element->clock, (GstObject *) clock); GST_UNLOCK (element); } /** * gst_element_get_clock: * @element: a #GstElement to get the clock of. * * Gets the clock of the element. If the element provides a clock, * this function will return this clock. For elements that do not * provide a clock, this function returns NULL. * * Returns: the #GstClock of the element. unref after usage. * * MT safe. */ GstClock * gst_element_get_clock (GstElement * element) { GstElementClass *oclass; g_return_val_if_fail (GST_IS_ELEMENT (element), NULL); oclass = GST_ELEMENT_GET_CLASS (element); if (oclass->get_clock) return oclass->get_clock (element); return NULL; } /** * gst_element_set_base_time: * @element: a #GstElement. * @time: the base time to set. * * Set the base time of an element. See @gst_element_get_base_time(). * * MT safe. */ void gst_element_set_base_time (GstElement * element, GstClockTime time) { g_return_if_fail (GST_IS_ELEMENT (element)); GST_LOCK (element); element->base_time = time; GST_UNLOCK (element); } /** * gst_element_get_base_time: * @element: a #GstElement. * * Returns the base time of the element. The base time is the * absolute time of the clock when this element was last put to * PLAYING. Substracting the base time from the clock time gives * the stream time of the element. * * Returns: the base time of the element. * * MT safe. */ GstClockTime gst_element_get_base_time (GstElement * element) { GstClockTime result; g_return_val_if_fail (GST_IS_ELEMENT (element), GST_CLOCK_TIME_NONE); GST_LOCK (element); result = element->base_time; GST_UNLOCK (element); return result; } #ifndef GST_DISABLE_INDEX /** * gst_element_is_indexable: * @element: a #GstElement. * * Queries if the element can be indexed. * * Returns: TRUE if the element can be indexed. * * MT safe. */ gboolean gst_element_is_indexable (GstElement * element) { gboolean result = FALSE; g_return_val_if_fail (GST_IS_ELEMENT (element), result); result = (GST_ELEMENT_GET_CLASS (element)->set_index != NULL); return result; } /** * gst_element_set_index: * @element: a #GstElement. * @index: a #GstIndex. * * Set the specified GstIndex on the element. * * MT safe. */ void gst_element_set_index (GstElement * element, GstIndex * index) { GstElementClass *oclass; g_return_if_fail (GST_IS_ELEMENT (element)); g_return_if_fail (GST_IS_INDEX (index)); oclass = GST_ELEMENT_GET_CLASS (element); if (oclass->set_index) oclass->set_index (element, index); } /** * gst_element_get_index: * @element: a #GstElement. * * Gets the index from the element. * * Returns: a #GstIndex or NULL when no index was set on the * element. unref after usage. * * MT safe. */ GstIndex * gst_element_get_index (GstElement * element) { GstElementClass *oclass; g_return_val_if_fail (GST_IS_ELEMENT (element), NULL); oclass = GST_ELEMENT_GET_CLASS (element); if (oclass->get_index) return oclass->get_index (element); return NULL; } #endif /** * gst_element_add_pad: * @element: a #GstElement to add the pad to. * @pad: the #GstPad to add to the element. * * Adds a pad (link point) to @element. @pad's parent will be set to @element; * see gst_object_set_parent() for refcounting information. * * Pads are not automatically activated so elements should perform the needed * steps to activate the pad. * * The pad and the element should be unlocked when calling this function. * * Returns: TRUE if the pad could be added. This function can fail when * passing bad arguments or when a pad with the same name already existed. * * MT safe. */ gboolean gst_element_add_pad (GstElement * element, GstPad * pad) { gchar *pad_name; g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE); g_return_val_if_fail (GST_IS_PAD (pad), FALSE); /* locking pad to look at the name */ GST_LOCK (pad); pad_name = g_strdup (GST_PAD_NAME (pad)); GST_CAT_INFO_OBJECT (GST_CAT_ELEMENT_PADS, element, "adding pad '%s'", GST_STR_NULL (pad_name)); GST_UNLOCK (pad); /* then check to see if there's already a pad by that name here */ GST_LOCK (element); if (G_UNLIKELY (!gst_object_check_uniqueness (element->pads, pad_name))) goto name_exists; /* try to set the pad's parent */ if (G_UNLIKELY (!gst_object_set_parent (GST_OBJECT_CAST (pad), GST_OBJECT_CAST (element)))) goto had_parent; g_free (pad_name); /* add it to the list */ switch (gst_pad_get_direction (pad)) { case GST_PAD_SRC: element->srcpads = g_list_prepend (element->srcpads, pad); element->numsrcpads++; break; case GST_PAD_SINK: element->sinkpads = g_list_prepend (element->sinkpads, pad); element->numsinkpads++; break; default: goto no_direction; } element->pads = g_list_prepend (element->pads, pad); element->numpads++; element->pads_cookie++; GST_UNLOCK (element); /* emit the NEW_PAD signal */ g_signal_emit (G_OBJECT (element), gst_element_signals[NEW_PAD], 0, pad); return TRUE; /* ERROR cases */ name_exists: { g_critical ("Padname %s is not unique in element %s, not adding", pad_name, GST_ELEMENT_NAME (element)); GST_UNLOCK (element); g_free (pad_name); return FALSE; } had_parent: { g_critical ("Pad %s already has parent when trying to add to element %s", pad_name, GST_ELEMENT_NAME (element)); GST_UNLOCK (element); g_free (pad_name); return FALSE; } no_direction: { GST_LOCK (pad); g_critical ("Trying to add pad %s to element %s, but it has no direction", GST_OBJECT_NAME (pad), GST_ELEMENT_NAME (element)); GST_UNLOCK (pad); GST_UNLOCK (element); return FALSE; } } /** * gst_element_remove_pad: * @element: a #GstElement to remove pad from. * @pad: the #GstPad to remove from the element. * * Removes @pad from @element. @pad will be destroyed if it has not been * referenced elsewhere. * * Returns: TRUE if the pad could be removed. Can return FALSE if the * pad is not belonging to the provided element or when wrong parameters * are passed to this function. * * MT safe. */ gboolean gst_element_remove_pad (GstElement * element, GstPad * pad) { GstPad *peer; g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE); g_return_val_if_fail (GST_IS_PAD (pad), FALSE); /* locking pad to look at the name and parent */ GST_LOCK (pad); GST_CAT_INFO_OBJECT (GST_CAT_ELEMENT_PADS, element, "removing pad '%s'", GST_STR_NULL (GST_PAD_NAME (pad))); if (G_UNLIKELY (GST_PAD_PARENT (pad) != element)) goto not_our_pad; GST_UNLOCK (pad); /* unlink */ if ((peer = gst_pad_get_peer (pad))) { /* window for MT unsafeness, someone else could unlink here * and then we call unlink with wrong pads. The unlink * function would catch this and safely return failed. */ if (GST_PAD_IS_SRC (pad)) gst_pad_unlink (pad, peer); else gst_pad_unlink (peer, pad); gst_object_unref (peer); } GST_LOCK (element); /* remove it from the list */ switch (gst_pad_get_direction (pad)) { case GST_PAD_SRC: element->srcpads = g_list_remove (element->srcpads, pad); element->numsrcpads--; break; case GST_PAD_SINK: element->sinkpads = g_list_remove (element->sinkpads, pad); element->numsinkpads--; break; default: g_critical ("Removing pad without direction???"); break; } element->pads = g_list_remove (element->pads, pad); element->numpads--; element->pads_cookie++; GST_UNLOCK (element); g_signal_emit (G_OBJECT (element), gst_element_signals[PAD_REMOVED], 0, pad); gst_object_unparent (GST_OBJECT (pad)); return TRUE; not_our_pad: { /* FIXME, locking order? */ GST_LOCK (element); g_critical ("Padname %s:%s does not belong to element %s when removing", GST_ELEMENT_NAME (GST_PAD_PARENT (pad)), GST_PAD_NAME (pad), GST_ELEMENT_NAME (element)); GST_UNLOCK (element); GST_UNLOCK (pad); return FALSE; } } /** * gst_element_no_more_pads: * @element: a #GstElement * * Use this function to signal that the element does not expect any more pads * to show up in the current pipeline. This function should be called whenever * pads have been added by the element itself. Elements with GST_PAD_SOMETIMES * pad templates use this in combination with autopluggers to figure out that * the element is done initializing its pads. * * MT safe. */ void gst_element_no_more_pads (GstElement * element) { g_return_if_fail (GST_IS_ELEMENT (element)); g_signal_emit (element, gst_element_signals[NO_MORE_PADS], 0); } static gint pad_compare_name (GstPad * pad1, const gchar * name) { gint result; GST_LOCK (pad1); result = strcmp (GST_PAD_NAME (pad1), name); GST_UNLOCK (pad1); return result; } /** * gst_element_get_static_pad: * @element: a #GstElement to find a static pad of. * @name: the name of the static #GstPad to retrieve. * * Retrieves a pad from @element by name. This version only retrieves * already-existing (i.e. 'static') pads. * * Returns: the requested #GstPad if found, otherwise NULL. unref after * usage. * * MT safe. */ GstPad * gst_element_get_static_pad (GstElement * element, const gchar * name) { GList *find; GstPad *result = NULL; g_return_val_if_fail (GST_IS_ELEMENT (element), NULL); g_return_val_if_fail (name != NULL, NULL); GST_LOCK (element); find = g_list_find_custom (element->pads, name, (GCompareFunc) pad_compare_name); if (find) { result = GST_PAD_CAST (find->data); gst_object_ref (result); } if (result == NULL) { GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "no such pad '%s' in element \"%s\"", name, GST_ELEMENT_NAME (element)); } else { GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "found pad %s:%s", GST_ELEMENT_NAME (element), name); } GST_UNLOCK (element); return result; } static GstPad * gst_element_request_pad (GstElement * element, GstPadTemplate * templ, const gchar * name) { GstPad *newpad = NULL; GstElementClass *oclass; oclass = GST_ELEMENT_GET_CLASS (element); if (oclass->request_new_pad) newpad = (oclass->request_new_pad) (element, templ, name); if (newpad) gst_object_ref (newpad); return newpad; } /** * gst_element_get_request_pad: * @element: a #GstElement to find a request pad of. * @name: the name of the request #GstPad to retrieve. * * Retrieves a pad from the element by name. This version only retrieves * request pads. * * Returns: requested #GstPad if found, otherwise NULL. Unref after usage. */ GstPad * gst_element_get_request_pad (GstElement * element, const gchar * name) { GstPadTemplate *templ = NULL; GstPad *pad; const gchar *req_name = NULL; gboolean templ_found = FALSE; GList *list; gint n; const gchar *data; gchar *str, *endptr = NULL; GstElementClass *class; g_return_val_if_fail (GST_IS_ELEMENT (element), NULL); g_return_val_if_fail (name != NULL, NULL); class = GST_ELEMENT_GET_CLASS (element); if (strstr (name, "%")) { templ = gst_element_class_get_pad_template (class, name); req_name = NULL; if (templ) templ_found = TRUE; } else { list = gst_element_class_get_pad_template_list (class); while (!templ_found && list) { templ = (GstPadTemplate *) list->data; if (templ->presence == GST_PAD_REQUEST) { /* Because of sanity checks in gst_pad_template_new(), we know that %s and %d, occurring at the end of the name_template, are the only possibilities. */ GST_CAT_DEBUG (GST_CAT_PADS, "comparing %s to %s", name, templ->name_template); if ((str = strchr (templ->name_template, '%')) && strncmp (templ->name_template, name, str - templ->name_template) == 0 && strlen (name) > str - templ->name_template) { data = name + (str - templ->name_template); if (*(str + 1) == 'd') { /* it's an int */ n = (gint) strtol (data, &endptr, 10); if (endptr && *endptr == '\0') { templ_found = TRUE; req_name = name; break; } } else { /* it's a string */ templ_found = TRUE; req_name = name; break; } } } list = list->next; } } if (!templ_found) return NULL; pad = gst_element_request_pad (element, templ, req_name); return pad; } /** * gst_element_get_pad: * @element: a #GstElement. * @name: the name of the pad to retrieve. * * Retrieves a pad from @element by name. Tries gst_element_get_static_pad() * first, then gst_element_get_request_pad(). * * Returns: the #GstPad if found, otherwise %NULL. Unref after usage. */ GstPad * gst_element_get_pad (GstElement * element, const gchar * name) { GstPad *pad; g_return_val_if_fail (GST_IS_ELEMENT (element), NULL); g_return_val_if_fail (name != NULL, NULL); pad = gst_element_get_static_pad (element, name); if (!pad) pad = gst_element_get_request_pad (element, name); return pad; } GstIteratorItem iterate_pad (GstIterator * it, GstPad * pad) { gst_object_ref (pad); return GST_ITERATOR_ITEM_PASS; } /** * gst_element_iterate_pads: * @element: a #GstElement to iterate pads of. * * Retrieves an iterattor of @element's pads. * * Returns: the #GstIterator of #GstPad. Unref each pad after use. * * MT safe. */ GstIterator * gst_element_iterate_pads (GstElement * element) { GstIterator *result; g_return_val_if_fail (GST_IS_ELEMENT (element), NULL); GST_LOCK (element); gst_object_ref (element); result = gst_iterator_new_list (GST_GET_LOCK (element), &element->pads_cookie, &element->pads, element, (GstIteratorItemFunction) iterate_pad, (GstIteratorDisposeFunction) gst_object_unref); GST_UNLOCK (element); return result; } static gint direction_filter (gconstpointer pad, gconstpointer direction) { if (GST_PAD_DIRECTION (pad) == GPOINTER_TO_INT (direction)) { /* pass the ref through */ return 0; } else { /* unref */ /* FIXME: this is very stupid */ gst_object_unref (GST_OBJECT_CAST (pad)); return 1; } } /** * gst_element_iterate_src_pads: * @element: a #GstElement. * * Retrieves an iterator of @element's source pads. * * Returns: the #GstIterator of #GstPad. Unref each pad after use. * * MT safe. */ GstIterator * gst_element_iterate_src_pads (GstElement * element) { g_return_val_if_fail (GST_IS_ELEMENT (element), NULL); return gst_iterator_filter (gst_element_iterate_pads (element), direction_filter, GINT_TO_POINTER (GST_PAD_SRC)); } /** * gst_element_iterate_sink_pads: * @element: a #GstElement. * * Retrieves an iterator of @element's sink pads. * * Returns: the #GstIterator of #GstPad. Unref each pad after use. * * MT safe. */ GstIterator * gst_element_iterate_sink_pads (GstElement * element) { g_return_val_if_fail (GST_IS_ELEMENT (element), NULL); return gst_iterator_filter (gst_element_iterate_pads (element), direction_filter, GINT_TO_POINTER (GST_PAD_SINK)); } /** * gst_element_class_add_pad_template: * @klass: the #GstElementClass to add the pad template to. * @templ: a #GstPadTemplate to add to the element class. * * Adds a padtemplate to an element class. This is mainly used in the _base_init * functions of classes. */ void gst_element_class_add_pad_template (GstElementClass * klass, GstPadTemplate * templ) { g_return_if_fail (GST_IS_ELEMENT_CLASS (klass)); g_return_if_fail (GST_IS_PAD_TEMPLATE (templ)); /* avoid registering pad templates with the same name */ g_return_if_fail (gst_element_class_get_pad_template (klass, templ->name_template) == NULL); klass->padtemplates = g_list_append (klass->padtemplates, gst_object_ref (templ)); klass->numpadtemplates++; } /** * gst_element_class_set_details: * @klass: class to set details for * @details: details to set * * Sets the detailed information for a #GstElementClass. * This function is for use in _base_init functions only. */ void gst_element_class_set_details (GstElementClass * klass, const GstElementDetails * details) { g_return_if_fail (GST_IS_ELEMENT_CLASS (klass)); g_return_if_fail (GST_IS_ELEMENT_DETAILS (details)); __gst_element_details_copy (&klass->details, details); } /** * gst_element_class_get_pad_template_list: * @element_class: a #GstElementClass to get pad templates of. * * Retrieves a list of the pad templates associated with @element_class. The * list must not be modified by the calling code. * If you use this function in the #GInstanceInitFunc of an object class * that has subclasses, make sure to pass the g_class parameter of the * #GInstanceInitFunc here. * * Returns: the #GList of padtemplates. */ GList * gst_element_class_get_pad_template_list (GstElementClass * element_class) { g_return_val_if_fail (GST_IS_ELEMENT_CLASS (element_class), NULL); return element_class->padtemplates; } /** * gst_element_class_get_pad_template: * @element_class: a #GstElementClass to get the pad template of. * @name: the name of the #GstPadTemplate to get. * * Retrieves a padtemplate from @element_class with the given name. * If you use this function in the #GInstanceInitFunc of an object class * that has subclasses, make sure to pass the g_class parameter of the * #GInstanceInitFunc here. * * Returns: the #GstPadTemplate with the given name, or NULL if none was found. * No unreferencing is necessary. */ GstPadTemplate * gst_element_class_get_pad_template (GstElementClass * element_class, const gchar * name) { GList *padlist; g_return_val_if_fail (GST_IS_ELEMENT_CLASS (element_class), NULL); g_return_val_if_fail (name != NULL, NULL); padlist = gst_element_class_get_pad_template_list (element_class); while (padlist) { GstPadTemplate *padtempl = (GstPadTemplate *) padlist->data; if (strcmp (padtempl->name_template, name) == 0) return padtempl; padlist = g_list_next (padlist); } return NULL; } static GstPad * gst_element_get_random_pad (GstElement * element, GstPadDirection dir) { GstPad *result = NULL; GList *pads; GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "getting a random pad"); switch (dir) { case GST_PAD_SRC: GST_LOCK (element); pads = element->srcpads; break; case GST_PAD_SINK: GST_LOCK (element); pads = element->sinkpads; break; default: goto wrong_direction; } for (; pads; pads = g_list_next (pads)) { GstPad *pad = GST_PAD (pads->data); GST_LOCK (pad); GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "checking pad %s:%s", GST_DEBUG_PAD_NAME (pad)); if (GST_PAD_IS_LINKED (pad)) { GST_UNLOCK (pad); result = pad; break; } else { GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "pad %s:%s is not linked", GST_DEBUG_PAD_NAME (pad)); } GST_UNLOCK (pad); } if (result) gst_object_ref (result); GST_UNLOCK (element); return result; /* ERROR handling */ wrong_direction: { g_warning ("unknown pad direction %d", dir); return NULL; } } /** * gst_element_send_event: * @element: a #GstElement to send the event to. * @event: the #GstEvent to send to the element. * * Sends an event to an element. If the element doesn't * implement an event handler, the event will be forwarded * to a random sink pad. This function takes owership of the * provided event so you should _ref it if you want to reuse * the event after this call. * * Returns: TRUE if the event was handled. * * MT safe. */ gboolean gst_element_send_event (GstElement * element, GstEvent * event) { GstElementClass *oclass; gboolean result = FALSE; g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE); g_return_val_if_fail (event != NULL, FALSE); oclass = GST_ELEMENT_GET_CLASS (element); if (oclass->send_event) { result = oclass->send_event (element, event); } else { GstPad *pad = gst_element_get_random_pad (element, GST_PAD_SINK); if (pad) { GstPad *peer = gst_pad_get_peer (pad); if (peer) { GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "sending event to random pad %s:%s", GST_DEBUG_PAD_NAME (pad)); result = gst_pad_send_event (peer, event); gst_object_unref (peer); } gst_object_unref (pad); } } GST_CAT_DEBUG (GST_CAT_ELEMENT_PADS, "can't send event on element %s", GST_ELEMENT_NAME (element)); return result; } /** * gst_element_seek: * @element: a #GstElement to send the event to. * @rate: The new playback rate * @format: The format of the seek values * @flags: The optional seek flags. * @cur_type: The type and flags for the new current position * @cur: The value of the new current position * @stop_type: The type and flags for the new stop position * @stop: The value of the new stop position * * Sends a seek event to an element. * * Returns: %TRUE if the event was handled. * * MT safe. */ gboolean gst_element_seek (GstElement * element, gdouble rate, GstFormat format, GstSeekFlags flags, GstSeekType cur_type, gint64 cur, GstSeekType stop_type, gint64 stop) { GstEvent *event; gboolean result; g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE); event = gst_event_new_seek (rate, format, flags, cur_type, cur, stop_type, stop); result = gst_element_send_event (element, event); return result; } /** * gst_element_get_query_types: * @element: a #GstElement to query * * Get an array of query types from the element. * If the element doesn't implement a query types function, * the query will be forwarded to a random sink pad. * * Returns: An array of #GstQueryType elements that should not * be freed or modified. * * MT safe. */ const GstQueryType * gst_element_get_query_types (GstElement * element) { GstElementClass *oclass; const GstQueryType *result = NULL; g_return_val_if_fail (GST_IS_ELEMENT (element), NULL); oclass = GST_ELEMENT_GET_CLASS (element); if (oclass->get_query_types) { result = oclass->get_query_types (element); } else { GstPad *pad = gst_element_get_random_pad (element, GST_PAD_SINK); if (pad) { GstPad *peer = gst_pad_get_peer (pad); if (peer) { result = gst_pad_get_query_types (peer); gst_object_unref (peer); } gst_object_unref (pad); } } return result; } /** * gst_element_query: * @element: a #GstElement to perform the query on. * @query: the #GstQuery. * * Performs a query on the given element. If the format is set * to GST_FORMAT_DEFAULT and this function returns TRUE, the * format pointer will hold the default format. * For element that don't implement a query handler, this function * forwards the query to a random usable sinkpad of this element. * * Returns: TRUE if the query could be performed. * * MT safe. */ gboolean gst_element_query (GstElement * element, GstQuery * query) { GstElementClass *oclass; gboolean result = FALSE; g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE); g_return_val_if_fail (query != NULL, FALSE); oclass = GST_ELEMENT_GET_CLASS (element); if (oclass->query) { result = oclass->query (element, query); } else { GstPad *pad = gst_element_get_random_pad (element, GST_PAD_SRC); if (pad) { result = gst_pad_query (pad, query); gst_object_unref (pad); } else { pad = gst_element_get_random_pad (element, GST_PAD_SINK); if (pad) { GstPad *peer = gst_pad_get_peer (pad); if (peer) { result = gst_pad_query (peer, query); gst_object_unref (peer); } gst_object_unref (pad); } } } return result; } /** * gst_element_post_message: * @element: a #GstElement posting the message * @message: a #GstMessage to post * * Post a message on the element's #GstBus. * * Returns: TRUE if the message was successfully posted. * * MT safe. */ gboolean gst_element_post_message (GstElement * element, GstMessage * message) { GstBus *bus; gboolean result = FALSE; GST_DEBUG ("posting message %p ...", message); g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE); g_return_val_if_fail (message != NULL, FALSE); GST_LOCK (element); bus = element->bus; if (G_UNLIKELY (bus == NULL)) { GST_DEBUG ("... but I won't because I have no bus"); GST_UNLOCK (element); gst_message_unref (message); return FALSE; } gst_object_ref (bus); GST_DEBUG ("... on bus %" GST_PTR_FORMAT, bus); GST_UNLOCK (element); result = gst_bus_post (bus, message); gst_object_unref (bus); return result; } /** * _gst_element_error_printf: * @format: the printf-like format to use, or NULL * * This function is only used internally by the #gst_element_error macro. * * Returns: a newly allocated string, or NULL if the format was NULL or "" * * MT safe. */ gchar * _gst_element_error_printf (const gchar * format, ...) { va_list args; gchar *buffer; if (format == NULL) return NULL; if (format[0] == 0) return NULL; va_start (args, format); buffer = g_strdup_vprintf (format, args); va_end (args); return buffer; } /** * gst_element_message_full: * @element: a #GstElement to send message from * @type: the #GstMessageType * @domain: the GStreamer GError domain this message belongs to * @code: the GError code belonging to the domain * @text: an allocated text string to be used as a replacement for the * default message connected to code, or NULL * @debug: an allocated debug message to be used as a replacement for the * default debugging information, or NULL * @file: the source code file where the error was generated * @function: the source code function where the error was generated * @line: the source code line where the error was generated * * Post an error or warning message on the bus from inside an element. * * MT safe. */ void gst_element_message_full (GstElement * element, GstMessageType type, GQuark domain, gint code, gchar * text, gchar * debug, const gchar * file, const gchar * function, gint line) { GError *gerror = NULL; gchar *name; gchar *sent_text; gchar *sent_debug; GstMessage *message = NULL; /* checks */ GST_DEBUG ("start"); g_return_if_fail (GST_IS_ELEMENT (element)); g_return_if_fail ((type == GST_MESSAGE_ERROR) || (type == GST_MESSAGE_WARNING)); /* check if we send the given text or the default error text */ if ((text == NULL) || (text[0] == 0)) { /* text could have come from g_strdup_printf (""); */ g_free (text); sent_text = gst_error_get_message (domain, code); } else sent_text = text; /* construct a sent_debug with extra information from source */ if ((debug == NULL) || (debug[0] == 0)) { /* debug could have come from g_strdup_printf (""); */ sent_debug = NULL; } else { name = gst_object_get_path_string (GST_OBJECT (element)); sent_debug = g_strdup_printf ("%s(%d): %s: %s:\n%s", file, line, function, name, debug ? debug : ""); g_free (name); } g_free (debug); /* create gerror and post message */ GST_CAT_INFO_OBJECT (GST_CAT_ERROR_SYSTEM, element, "posting message: %s", sent_text); gerror = g_error_new_literal (domain, code, sent_text); if (type == GST_MESSAGE_ERROR) { message = gst_message_new_error (GST_OBJECT (element), gerror, sent_debug); } else if (type == GST_MESSAGE_WARNING) { message = gst_message_new_warning (GST_OBJECT (element), gerror, sent_debug); } else { g_assert_not_reached (); } gst_element_post_message (element, message); GST_CAT_INFO_OBJECT (GST_CAT_ERROR_SYSTEM, element, "posted message: %s", sent_text); /* cleanup */ g_error_free (gerror); g_free (sent_debug); g_free (sent_text); } /** * gst_element_is_locked_state: * @element: a #GstElement. * * Checks if the state of an element is locked. * If the state of an element is locked, state changes of the parent don't * affect the element. * This way you can leave currently unused elements inside bins. Just lock their * state before changing the state from #GST_STATE_NULL. * * Returns: TRUE, if the element's state is locked. * * MT safe. */ gboolean gst_element_is_locked_state (GstElement * element) { gboolean result = FALSE; g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE); GST_LOCK (element); result = GST_FLAG_IS_SET (element, GST_ELEMENT_LOCKED_STATE); GST_UNLOCK (element); return result; } /** * gst_element_set_locked_state: * @element: a #GstElement * @locked_state: TRUE to lock the element's state * * Locks the state of an element, so state changes of the parent don't affect * this element anymore. * * Returns: TRUE if the state was changed, FALSE if bad params were given or * the element was already in the correct state. * * MT safe. */ gboolean gst_element_set_locked_state (GstElement * element, gboolean locked_state) { gboolean old; g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE); GST_LOCK (element); old = GST_FLAG_IS_SET (element, GST_ELEMENT_LOCKED_STATE); if (G_UNLIKELY (old == locked_state)) goto was_ok; if (locked_state) { GST_CAT_DEBUG (GST_CAT_STATES, "locking state of element %s", GST_ELEMENT_NAME (element)); GST_FLAG_SET (element, GST_ELEMENT_LOCKED_STATE); } else { GST_CAT_DEBUG (GST_CAT_STATES, "unlocking state of element %s", GST_ELEMENT_NAME (element)); GST_FLAG_UNSET (element, GST_ELEMENT_LOCKED_STATE); } GST_UNLOCK (element); return TRUE; was_ok: GST_UNLOCK (element); return FALSE; } /** * gst_element_sync_state_with_parent: * @element: a #GstElement. * * Tries to change the state of the element to the same as its parent. * If this function returns FALSE, the state of element is undefined. * * Returns: TRUE, if the element's state could be synced to the parent's state. */ gboolean gst_element_sync_state_with_parent (GstElement * element) { GstElement *parent; g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE); parent = GST_ELEMENT (GST_ELEMENT_PARENT (element)); g_return_val_if_fail (GST_IS_BIN (parent), FALSE); GST_CAT_DEBUG (GST_CAT_STATES, "syncing state of element %s (%s) to %s (%s)", GST_ELEMENT_NAME (element), gst_element_state_get_name (GST_STATE (element)), GST_ELEMENT_NAME (parent), gst_element_state_get_name (GST_STATE (parent))); if (gst_element_set_state (element, GST_STATE (parent)) == GST_STATE_CHANGE_FAILURE) { return FALSE; } return TRUE; } /* MT safe */ static GstStateChangeReturn gst_element_get_state_func (GstElement * element, GstState * state, GstState * pending, GTimeVal * timeout) { GstStateChangeReturn ret = GST_STATE_CHANGE_FAILURE; GstState old_pending; GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "getting state"); GST_STATE_LOCK (element); /* we got an error, report immediatly */ if (GST_STATE_NO_PREROLL (element)) { ret = GST_STATE_CHANGE_NO_PREROLL; goto done; } /* we got an error, report immediatly */ if (GST_STATE_ERROR (element)) { ret = GST_STATE_CHANGE_FAILURE; goto done; } old_pending = GST_STATE_PENDING (element); if (old_pending != GST_STATE_VOID_PENDING) { GTimeVal *timeval, abstimeout; GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "wait for pending"); if (timeout) { /* make timeout absolute */ g_get_current_time (&abstimeout); g_time_val_add (&abstimeout, timeout->tv_sec * G_USEC_PER_SEC + timeout->tv_usec); timeval = &abstimeout; } else { timeval = NULL; } /* we have a pending state change, wait for it to complete */ if (!GST_STATE_TIMED_WAIT (element, timeval)) { GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "timeout"); /* timeout triggered */ ret = GST_STATE_CHANGE_ASYNC; } else { /* could be success or failure */ if (old_pending == GST_STATE (element)) { GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "got success"); ret = GST_STATE_CHANGE_SUCCESS; } else { GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "got failure"); ret = GST_STATE_CHANGE_FAILURE; } } } /* if nothing is pending anymore we can return SUCCESS */ if (GST_STATE_PENDING (element) == GST_STATE_VOID_PENDING) { GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "nothing pending"); ret = GST_STATE_CHANGE_SUCCESS; } done: if (state) *state = GST_STATE (element); if (pending) *pending = GST_STATE_PENDING (element); GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "state current: %s, pending: %s, error: %d, no_preroll: %d, result: %d", gst_element_state_get_name (GST_STATE (element)), gst_element_state_get_name (GST_STATE_PENDING (element)), GST_STATE_ERROR (element), GST_STATE_NO_PREROLL (element), ret); GST_STATE_UNLOCK (element); return ret; } /** * gst_element_get_state: * @element: a #GstElement to get the state of. * @state: a pointer to #GstState to hold the state. Can be NULL. * @pending: a pointer to #GstState to hold the pending state. * Can be NULL. * @timeout: a #GTimeVal to specify the timeout for an async * state change or NULL for infinite timeout. * * Gets the state of the element. * * For elements that performed an ASYNC state change, as reported by * #gst_element_set_state(), this function will block up to the * specified timeout value for the state change to complete. * If the element completes the state change or goes into * an error, this function returns immediatly with a return value of * GST_STATE_CHANGE_SUCCESS or GST_STATE_CHANGE_FAILURE respectively. * * Returns: GST_STATE_CHANGE_SUCCESS if the element has no more pending state and * the last state change succeeded, GST_STATE_CHANGE_ASYNC * if the element is still performing a state change or * GST_STATE_CHANGE_FAILURE if the last state change failed. * * MT safe. */ GstStateChangeReturn gst_element_get_state (GstElement * element, GstState * state, GstState * pending, GTimeVal * timeout) { GstElementClass *oclass; GstStateChangeReturn result = GST_STATE_CHANGE_FAILURE; g_return_val_if_fail (GST_IS_ELEMENT (element), GST_STATE_CHANGE_FAILURE); oclass = GST_ELEMENT_GET_CLASS (element); if (oclass->get_state) result = (oclass->get_state) (element, state, pending, timeout); return result; } /** * gst_element_abort_state: * @element: a #GstElement to abort the state of. * * Abort the state change of the element. This function is used * by elements that do asynchronous state changes and find out * something is wrong. * * This function should be called with the STATE_LOCK held. * * MT safe. */ void gst_element_abort_state (GstElement * element) { GstState pending; g_return_if_fail (GST_IS_ELEMENT (element)); pending = GST_STATE_PENDING (element); if (pending != GST_STATE_VOID_PENDING && !GST_STATE_ERROR (element)) { #ifndef GST_DISABLE_GST_DEBUG GstState old_state = GST_STATE (element); #endif GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "aborting state from %s to %s", gst_element_state_get_name (old_state), gst_element_state_get_name (pending)); /* flag error */ GST_STATE_ERROR (element) = TRUE; GST_STATE_BROADCAST (element); } } /** * gst_element_commit_state: * @element: a #GstElement to commit the state of. * * Commit the state change of the element. This function is used * by elements that do asynchronous state changes. * * This function can only be called with the STATE_LOCK held. * * MT safe. */ void gst_element_commit_state (GstElement * element) { GstState pending; GstMessage *message; g_return_if_fail (GST_IS_ELEMENT (element)); pending = GST_STATE_PENDING (element); if (pending != GST_STATE_VOID_PENDING) { GstState old_state = GST_STATE (element); GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "commiting state from %s to %s", gst_element_state_get_name (old_state), gst_element_state_get_name (pending)); GST_STATE (element) = pending; GST_STATE_PENDING (element) = GST_STATE_VOID_PENDING; GST_STATE_ERROR (element) = FALSE; g_signal_emit (G_OBJECT (element), gst_element_signals[STATE_CHANGE], 0, old_state, pending); message = gst_message_new_state_changed (GST_OBJECT (element), old_state, pending); gst_element_post_message (element, message); GST_STATE_BROADCAST (element); } } /** * gst_element_lost_state: * @element: a #GstElement the state is lost of * * Brings the element to the lost state. The current state of the * element is copied to the pending state so that any call to * #gst_element_get_state() will return ASYNC. * This is mostly used for elements that lost their preroll buffer * in the PAUSED state after a flush, they become PAUSED again * if a new preroll buffer is queued. * This function can only be called when the element is currently * not in error or an async state change. * * This function can only be called with the STATE_LOCK held. * * MT safe. */ void gst_element_lost_state (GstElement * element) { g_return_if_fail (GST_IS_ELEMENT (element)); if (GST_STATE_PENDING (element) == GST_STATE_VOID_PENDING && !GST_STATE_ERROR (element)) { GstState current_state = GST_STATE (element); GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "lost state of %s", gst_element_state_get_name (current_state)); GST_STATE_PENDING (element) = current_state; GST_STATE_ERROR (element) = FALSE; } } /** * gst_element_set_state: * @element: a #GstElement to change state of. * @state: the element's new #GstState. * * Sets the state of the element. This function will try to set the * requested state by going through all the intermediary states and calling * the class's state change function for each. * * Returns: Result of the state change using #GstStateChangeReturn. * * MT safe. */ GstStateChangeReturn gst_element_set_state (GstElement * element, GstState state) { GstElementClass *oclass; GstState current; GstStateChangeReturn return_val = GST_STATE_CHANGE_SUCCESS; GstStateChangeReturn ret; GstState pending; GTimeVal tv; g_return_val_if_fail (GST_IS_ELEMENT (element), GST_STATE_CHANGE_FAILURE); /* get current element state, need to call the method so that * we call the virtual method and subclasses can implement their * own algorithms */ GST_TIME_TO_TIMEVAL (0, tv); ret = gst_element_get_state (element, ¤t, &pending, &tv); /* get the element state lock */ GST_STATE_LOCK (element); /* this is the state we should go to */ GST_STATE_FINAL (element) = state; if (ret == GST_STATE_CHANGE_ASYNC) { gst_element_commit_state (element); gst_element_lost_state (element); } /* start with the current state */ current = GST_STATE (element); GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "setting state from %s to %s", gst_element_state_get_name (current), gst_element_state_get_name (state)); oclass = GST_ELEMENT_GET_CLASS (element); /* We always perform at least one state change, even if the * current state is equal to the required state. This is needed * for bins that sync their children. */ do { GstState pending; /* calculate the pending state */ if (current < state) pending = current + 1; else if (current > state) pending = current - 1; else pending = current; /* set the pending state variable */ GST_STATE_PENDING (element) = pending; GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "%s: setting state from %s to %s", (pending != state ? "intermediate" : "final"), gst_element_state_get_name (current), gst_element_state_get_name (pending)); /* call the state change function so it can set the state */ if (oclass->change_state) return_val = (oclass->change_state) (element, GST_STATE_CHANGE (element)); else return_val = GST_STATE_CHANGE_FAILURE; /* clear the error and preroll flag, we need to do that after * calling the virtual change_state function so that it can use the * old previous value. */ GST_STATE_ERROR (element) = FALSE; GST_STATE_NO_PREROLL (element) = FALSE; switch (return_val) { case GST_STATE_CHANGE_FAILURE: GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "have failed change_state return"); /* state change failure exits the loop */ gst_element_abort_state (element); goto exit; case GST_STATE_CHANGE_ASYNC: GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "element will change state async"); /* an async state change exits the loop, we can only * go to the next state change when this one completes. */ goto exit; case GST_STATE_CHANGE_SUCCESS: GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "element changed state successfully"); /* we can commit the state now and proceed to the next state */ gst_element_commit_state (element); GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "commited state"); break; case GST_STATE_CHANGE_NO_PREROLL: GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "element changed state successfully and can't preroll"); /* we can commit the state now and proceed to the next state */ gst_element_commit_state (element); GST_STATE_NO_PREROLL (element) = TRUE; GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "commited state"); break; default: goto invalid_return; } /* get the current state of the element and see if we need to do more * state changes */ current = GST_STATE (element); } while (current != state); exit: GST_STATE_FINAL (element) = GST_STATE_VOID_PENDING; GST_STATE_UNLOCK (element); GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "exit state change"); return return_val; /* ERROR */ invalid_return: { GST_STATE_FINAL (element) = GST_STATE_VOID_PENDING; GST_STATE_UNLOCK (element); /* somebody added a GST_STATE_ and forgot to do stuff here ! */ g_critical ("unknown return value %d from a state change function", return_val); return GST_STATE_CHANGE_FAILURE; } } /* gst_iterator_fold functions for pads_activate */ static gboolean activate_pads (GstPad * pad, GValue * ret, gboolean * active) { if (!gst_pad_set_active (pad, *active)) g_value_set_boolean (ret, FALSE); else if (!*active) gst_pad_set_caps (pad, NULL); gst_object_unref (pad); return TRUE; } /* returns false on error or early cutout of the fold, true otherwise */ static gboolean iterator_fold_with_resync (GstIterator * iter, GstIteratorFoldFunction func, GValue * ret, gpointer user_data) { GstIteratorResult ires; gboolean res = TRUE; while (1) { ires = gst_iterator_fold (iter, func, ret, user_data); switch (ires) { case GST_ITERATOR_RESYNC: gst_iterator_resync (iter); break; case GST_ITERATOR_DONE: res = TRUE; goto done; default: res = FALSE; goto done; } } done: return res; } /* is called with STATE_LOCK */ static gboolean gst_element_pads_activate (GstElement * element, gboolean active) { GValue ret = { 0, }; GstIterator *iter; gboolean fold_ok; /* no need to unset this later, it's just a boolean */ g_value_init (&ret, G_TYPE_BOOLEAN); g_value_set_boolean (&ret, TRUE); iter = gst_element_iterate_src_pads (element); fold_ok = iterator_fold_with_resync (iter, (GstIteratorFoldFunction) activate_pads, &ret, &active); gst_iterator_free (iter); if (!fold_ok || !g_value_get_boolean (&ret)) return FALSE; iter = gst_element_iterate_sink_pads (element); fold_ok = iterator_fold_with_resync (iter, (GstIteratorFoldFunction) activate_pads, &ret, &active); gst_iterator_free (iter); if (!fold_ok || !g_value_get_boolean (&ret)) return FALSE; return TRUE; } /* is called with STATE_LOCK */ static GstStateChangeReturn gst_element_change_state (GstElement * element, GstStateChange transition) { GstState state, pending; GstStateChangeReturn result = GST_STATE_CHANGE_SUCCESS; g_return_val_if_fail (GST_IS_ELEMENT (element), GST_STATE_CHANGE_FAILURE); state = GST_STATE (element); pending = GST_STATE_PENDING (element); /* if the element already is in the given state, we just return success */ if (pending == GST_STATE_VOID_PENDING || state == GST_STATE_PENDING (element)) { GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "element is already in the %s state", gst_element_state_get_name (state)); if (GST_STATE_NO_PREROLL (element)) return GST_STATE_CHANGE_NO_PREROLL; else return GST_STATE_CHANGE_SUCCESS; } GST_CAT_LOG_OBJECT (GST_CAT_STATES, element, "default handler tries setting state from %s to %s (%04x)", gst_element_state_get_name (state), gst_element_state_get_name (pending), transition); switch (transition) { case GST_STATE_CHANGE_NULL_TO_READY: break; case GST_STATE_CHANGE_READY_TO_PAUSED: if (!gst_element_pads_activate (element, TRUE)) { result = GST_STATE_CHANGE_FAILURE; } break; case GST_STATE_CHANGE_PAUSED_TO_PLAYING: break; case GST_STATE_CHANGE_PLAYING_TO_PAUSED: break; case GST_STATE_CHANGE_PAUSED_TO_READY: case GST_STATE_CHANGE_READY_TO_NULL: /* deactivate pads in both cases, since they are activated on ready->paused but the element might not have made it to paused */ if (!gst_element_pads_activate (element, FALSE)) { result = GST_STATE_CHANGE_FAILURE; } else { GST_LOCK (element); element->base_time = 0; GST_UNLOCK (element); } break; default: /* this will catch real but unhandled state changes; * can only be caused by: * - a new state was added * - somehow the element was asked to jump across an intermediate state */ g_warning ("Unhandled state change from %s to %s", gst_element_state_get_name (state), gst_element_state_get_name (pending)); break; } return result; } /** * gst_element_get_factory: * @element: a #GstElement to request the element factory of. * * Retrieves the factory that was used to create this element. * * Returns: the #GstElementFactory used for creating this element. */ GstElementFactory * gst_element_get_factory (GstElement * element) { g_return_val_if_fail (GST_IS_ELEMENT (element), NULL); return GST_ELEMENT_GET_CLASS (element)->elementfactory; } static void gst_element_dispose (GObject * object) { GstElement *element = GST_ELEMENT (object); GST_CAT_INFO_OBJECT (GST_CAT_REFCOUNTING, element, "dispose"); /* ref so we don't hit 0 again */ gst_object_ref (object); /* first we break all our links with the outside */ while (element->pads) { gst_element_remove_pad (element, GST_PAD_CAST (element->pads->data)); } if (G_UNLIKELY (element->pads != 0)) { g_critical ("could not remove pads from element %s", GST_STR_NULL (GST_OBJECT_NAME (object))); } GST_LOCK (element); gst_object_replace ((GstObject **) & element->clock, NULL); gst_object_replace ((GstObject **) & element->bus, NULL); GST_UNLOCK (element); GST_CAT_INFO_OBJECT (GST_CAT_REFCOUNTING, element, "dispose parent"); G_OBJECT_CLASS (parent_class)->dispose (object); } static void gst_element_finalize (GObject * object) { GstElement *element = GST_ELEMENT (object); GST_CAT_INFO_OBJECT (GST_CAT_REFCOUNTING, element, "finalize"); GST_STATE_LOCK (element); if (element->state_cond) g_cond_free (element->state_cond); element->state_cond = NULL; GST_STATE_UNLOCK (element); g_mutex_free (element->state_lock); GST_CAT_INFO_OBJECT (GST_CAT_REFCOUNTING, element, "finalize parent"); G_OBJECT_CLASS (parent_class)->finalize (object); } #ifndef GST_DISABLE_LOADSAVE /** * gst_element_save_thyself: * @element: a #GstElement to save. * @parent: the xml parent node. * * Saves the element as part of the given XML structure. * * Returns: the new #xmlNodePtr. */ static xmlNodePtr gst_element_save_thyself (GstObject * object, xmlNodePtr parent) { GList *pads; GstElementClass *oclass; GParamSpec **specs, *spec; guint nspecs; gint i; GValue value = { 0, }; GstElement *element; g_return_val_if_fail (GST_IS_ELEMENT (object), parent); element = GST_ELEMENT (object); oclass = GST_ELEMENT_GET_CLASS (element); xmlNewChild (parent, NULL, (xmlChar *) "name", (xmlChar *) GST_ELEMENT_NAME (element)); if (oclass->elementfactory != NULL) { GstElementFactory *factory = (GstElementFactory *) oclass->elementfactory; xmlNewChild (parent, NULL, (xmlChar *) "type", (xmlChar *) GST_PLUGIN_FEATURE (factory)->name); } /* params */ specs = g_object_class_list_properties (G_OBJECT_GET_CLASS (object), &nspecs); for (i = 0; i < nspecs; i++) { spec = specs[i]; if (spec->flags & G_PARAM_READABLE) { xmlNodePtr param; char *contents; g_value_init (&value, G_PARAM_SPEC_VALUE_TYPE (spec)); g_object_get_property (G_OBJECT (element), spec->name, &value); param = xmlNewChild (parent, NULL, (xmlChar *) "param", NULL); xmlNewChild (param, NULL, (xmlChar *) "name", (xmlChar *) spec->name); if (G_IS_PARAM_SPEC_STRING (spec)) contents = g_value_dup_string (&value); else if (G_IS_PARAM_SPEC_ENUM (spec)) contents = g_strdup_printf ("%d", g_value_get_enum (&value)); else if (G_IS_PARAM_SPEC_INT64 (spec)) contents = g_strdup_printf ("%" G_GINT64_FORMAT, g_value_get_int64 (&value)); else contents = g_strdup_value_contents (&value); xmlNewChild (param, NULL, (xmlChar *) "value", (xmlChar *) contents); g_free (contents); g_value_unset (&value); } } g_free (specs); pads = GST_ELEMENT_PADS (element); while (pads) { GstPad *pad = GST_PAD (pads->data); /* figure out if it's a direct pad or a ghostpad */ if (GST_ELEMENT (GST_OBJECT_PARENT (pad)) == element) { xmlNodePtr padtag = xmlNewChild (parent, NULL, (xmlChar *) "pad", NULL); gst_object_save_thyself (GST_OBJECT (pad), padtag); } pads = g_list_next (pads); } return parent; } static void gst_element_restore_thyself (GstObject * object, xmlNodePtr self) { xmlNodePtr children; GstElement *element; gchar *name = NULL; gchar *value = NULL; element = GST_ELEMENT (object); g_return_if_fail (element != NULL); /* parameters */ children = self->xmlChildrenNode; while (children) { if (!strcmp ((char *) children->name, "param")) { xmlNodePtr child = children->xmlChildrenNode; while (child) { if (!strcmp ((char *) child->name, "name")) { name = (gchar *) xmlNodeGetContent (child); } else if (!strcmp ((char *) child->name, "value")) { value = (gchar *) xmlNodeGetContent (child); } child = child->next; } /* FIXME: can this just be g_object_set ? */ gst_util_set_object_arg (G_OBJECT (element), name, value); /* g_object_set (G_OBJECT (element), name, value, NULL); */ g_free (name); g_free (value); } children = children->next; } /* pads */ children = self->xmlChildrenNode; while (children) { if (!strcmp ((char *) children->name, "pad")) { gst_pad_load_and_link (children, GST_OBJECT (element)); } children = children->next; } if (GST_OBJECT_CLASS (parent_class)->restore_thyself) (GST_OBJECT_CLASS (parent_class)->restore_thyself) (object, self); } #endif /* GST_DISABLE_LOADSAVE */ static void gst_element_set_bus_func (GstElement * element, GstBus * bus) { g_return_if_fail (GST_IS_ELEMENT (element)); GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, element, "setting bus to %p", bus); GST_LOCK (element); gst_object_replace ((GstObject **) & GST_ELEMENT_BUS (element), GST_OBJECT (bus)); GST_UNLOCK (element); } /** * gst_element_set_bus: * @element: a #GstElement to set the bus of. * @bus: the #GstBus to set. * * Sets the bus of the element. For internal use only, unless you're * testing elements. * * MT safe. */ void gst_element_set_bus (GstElement * element, GstBus * bus) { GstElementClass *oclass; g_return_if_fail (GST_IS_ELEMENT (element)); oclass = GST_ELEMENT_GET_CLASS (element); if (oclass->set_bus) oclass->set_bus (element, bus); } /** * gst_element_get_bus: * @element: a #GstElement to get the bus of. * * Returns the bus of the element. * * Returns: the element's #GstBus. unref after usage. * * MT safe. */ GstBus * gst_element_get_bus (GstElement * element) { GstBus *result = NULL; g_return_val_if_fail (GST_IS_ELEMENT (element), result); GST_LOCK (element); result = GST_ELEMENT_BUS (element); gst_object_ref (result); GST_UNLOCK (element); GST_DEBUG_OBJECT (element, "got bus %" GST_PTR_FORMAT, result); return result; }