/* 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 "gstmarshal.h" #include "gsterror.h" #include "gstevent.h" #include "gstutils.h" #include "gstinfo.h" #include "gst-i18n-lib.h" #include "gstscheduler.h" #include "gstbus.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 GstElementStateReturn gst_element_change_state (GstElement * element); static GstElementStateReturn gst_element_get_state_func (GstElement * element, GstElementState * state, GstElementState * pending, GTimeVal * timeout); static void gst_element_set_manager_func (GstElement * element, GstPipeline * manager); static void gst_element_set_bus_func (GstElement * element, GstBus * bus); static void gst_element_set_scheduler_func (GstElement * element, GstScheduler * scheduler); #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); gst_element_signals[STATE_CHANGE] = g_signal_new ("state-change", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstElementClass, state_change), NULL, NULL, gst_marshal_VOID__INT_INT, G_TYPE_NONE, 2, G_TYPE_INT, G_TYPE_INT); gst_element_signals[NEW_PAD] = g_signal_new ("new-pad", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstElementClass, new_pad), NULL, NULL, gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, G_TYPE_OBJECT); 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); 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_manager = GST_DEBUG_FUNCPTR (gst_element_set_manager_func); klass->set_bus = GST_DEBUG_FUNCPTR (gst_element_set_bus_func); klass->set_scheduler = GST_DEBUG_FUNCPTR (gst_element_set_scheduler_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->numpads = 0; element->numsrcpads = 0; element->numsinkpads = 0; element->pads_cookie = 0; element->pads = NULL; element->srcpads = NULL; element->sinkpads = NULL; element->manager = NULL; element->clock = NULL; element->sched_private = NULL; 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); } /** * 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; } #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 automatically activated when the element is in state PLAYING. * * 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: /* can happen for ghost pads */ break; } element->pads = g_list_prepend (element->pads, pad); element->numpads++; element->pads_cookie++; GST_UNLOCK (element); GST_STATE_LOCK (element); /* activate pad when we are playing */ if (GST_STATE (element) == GST_STATE_PLAYING) /* FIXME, figure out mode */ gst_pad_set_active (pad, GST_ACTIVATE_PUSH); GST_STATE_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; } } /** * gst_element_add_ghost_pad: * @element: a #GstElement to add the ghost pad to. * @pad: the #GstPad from which the new ghost pad will be created. * @name: the name of the new ghost pad, or NULL to assign a unique name * automatically. * * Creates a ghost pad from @pad, and adds it to @element via * gst_element_add_pad(). * * Returns: the added ghost #GstPad, or NULL on error. * * MT safe. */ GstPad * gst_element_add_ghost_pad (GstElement * element, GstPad * pad, const gchar * name) { GstPad *ghostpad; g_return_val_if_fail (GST_IS_ELEMENT (element), NULL); g_return_val_if_fail (GST_IS_PAD (pad), NULL); ghostpad = gst_ghost_pad_new (name, pad); if (!gst_element_add_pad (element, ghostpad)) { gst_object_unref (GST_OBJECT (ghostpad)); ghostpad = NULL; } return ghostpad; } /** * 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) { 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 and parent */ GST_LOCK (pad); pad_name = g_strdup (GST_PAD_NAME (pad)); GST_CAT_INFO_OBJECT (GST_CAT_ELEMENT_PADS, element, "removing pad '%s'", GST_STR_NULL (pad_name)); if (G_UNLIKELY (GST_PAD_PARENT (pad) != element)) goto not_our_pad; GST_UNLOCK (pad); g_free (pad_name); /* FIXME, is this redundant with pad disposal? */ if (GST_IS_REAL_PAD (pad)) { GstPad *peer = gst_pad_get_peer (pad); /* unlink */ if (peer != NULL) { /* 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, GST_PAD_CAST (peer)); else gst_pad_unlink (GST_PAD_CAST (peer), pad); gst_object_unref (GST_OBJECT (peer)); } } else if (GST_IS_GHOST_PAD (pad)) { g_object_set (pad, "real-pad", NULL, NULL); } 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: /* can happen for ghost pads */ 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); g_free (pad_name); 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 (GST_OBJECT_CAST (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); 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. */ 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 (GST_OBJECT_CAST (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 pads. * * 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 (GST_OBJECT (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; } /** * 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 (GST_OBJECT (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"); GST_LOCK (element); switch (dir) { case GST_PAD_SRC: pads = element->srcpads; break; case GST_PAD_SINK: pads = element->sinkpads; break; default: g_warning ("unknown pad direction"); return NULL; } 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 (GST_OBJECT (result)); GST_UNLOCK (element); return result; } /** * gst_element_get_event_masks: * @element: a #GstElement to query * * Get an array of event masks from the element. * If the element doesn't implement an event masks function, * the query will be forwarded to a random linked sink pad. * * Returns: An array of #GstEventMask elements. The array * cannot be modified or freed. * * MT safe. */ const GstEventMask * gst_element_get_event_masks (GstElement * element) { GstElementClass *oclass; const GstEventMask *result = NULL; g_return_val_if_fail (GST_IS_ELEMENT (element), NULL); oclass = GST_ELEMENT_GET_CLASS (element); if (oclass->get_event_masks) { result = oclass->get_event_masks (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_event_masks (peer); gst_object_unref (GST_OBJECT (peer)); } gst_object_unref (GST_OBJECT (pad)); } } return result; } /** * 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 (GST_OBJECT (peer)); } gst_object_unref (GST_OBJECT (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. * @seek_type: the method to use for seeking. * @offset: the offset to seek to. * * Sends a seek event to an element. * * Returns: TRUE if the event was handled. * * MT safe. */ gboolean gst_element_seek (GstElement * element, GstSeekType seek_type, guint64 offset) { GstEvent *event = gst_event_new_seek (seek_type, offset); gboolean result; 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 (GST_OBJECT (peer)); } gst_object_unref (GST_OBJECT (pad)); } } return result; } /** * gst_element_query: * @element: a #GstElement to perform the query on. * @type: the #GstQueryType. * @format: the #GstFormat pointer to hold the format of the result. * @value: the pointer to the value of the result. * * 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, GstQueryType type, GstFormat * format, gint64 * value) { GstElementClass *oclass; gboolean result = FALSE; g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE); g_return_val_if_fail (format != NULL, FALSE); g_return_val_if_fail (value != NULL, FALSE); oclass = GST_ELEMENT_GET_CLASS (element); if (oclass->query) { result = oclass->query (element, type, format, value); } else { GstPad *pad = gst_element_get_random_pad (element, GST_PAD_SRC); if (pad) { result = gst_pad_query (pad, type, format, value); gst_object_unref (GST_OBJECT (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, type, format, value); gst_object_unref (GST_OBJECT (peer)); } gst_object_unref (GST_OBJECT (pad)); } } } return result; } /** * gst_element_get_formats: * @element: a #GstElement to query * * Get an array of formats from the element. * If the element doesn't implement a formats function, * the query will be forwarded to a random sink pad. * * Returns: An array of #GstFormat elements. * * MT safe. */ const GstFormat * gst_element_get_formats (GstElement * element) { GstElementClass *oclass; const GstFormat *result = NULL; g_return_val_if_fail (GST_IS_ELEMENT (element), NULL); oclass = GST_ELEMENT_GET_CLASS (element); if (oclass->get_formats) { result = oclass->get_formats (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_formats (peer); gst_object_unref (GST_OBJECT (peer)); } gst_object_unref (GST_OBJECT (pad)); } } return result; } /** * gst_element_convert: * @element: a #GstElement to invoke the converter on. * @src_format: the source #GstFormat. * @src_value: the source value. * @dest_format: a pointer to the destination #GstFormat. * @dest_value: a pointer to the destination value. * * Invokes a conversion on the element. * If the element doesn't implement a convert function, * the query will be forwarded to a random sink pad. * * Returns: TRUE if the conversion could be performed. * * MT safe. */ gboolean gst_element_convert (GstElement * element, GstFormat src_format, gint64 src_value, GstFormat * dest_format, gint64 * dest_value) { GstElementClass *oclass; gboolean result = FALSE; g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE); g_return_val_if_fail (dest_format != NULL, FALSE); g_return_val_if_fail (dest_value != NULL, FALSE); if (src_format == *dest_format) { *dest_value = src_value; return TRUE; } oclass = GST_ELEMENT_GET_CLASS (element); if (oclass->convert) { result = oclass->convert (element, src_format, src_value, dest_format, dest_value); } 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_convert (peer, src_format, src_value, dest_format, dest_value); gst_object_unref (GST_OBJECT (peer)); } gst_object_unref (GST_OBJECT (pad)); } } return result; } /** * gst_element_post_message: * @element: a #GstElement posting the message * @message: a #GstMessage to post * * Post a message on the elements #GstBus. * * Returns: TRUE if the message was successfuly 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_data_unref (GST_DATA (message)); return FALSE; } gst_object_ref (GST_OBJECT (bus)); GST_DEBUG ("... on bus %p", bus); GST_UNLOCK (element); result = gst_bus_post (bus, message); gst_object_unref (GST_OBJECT (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_text (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 { message = gst_message_new_warning (GST_OBJECT (element), gerror, sent_debug); } gst_element_post_message (element, message); GST_CAT_INFO_OBJECT (GST_CAT_ERROR_SYSTEM, element, "posted message: %s", sent_text); /* cleanup */ g_free (sent_text); /* sent_debug is not part of the gerror, so don't free it here */ } /** * 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_FAILURE) { return FALSE; } return TRUE; } /* MT safe */ static GstElementStateReturn gst_element_get_state_func (GstElement * element, GstElementState * state, GstElementState * pending, GTimeVal * timeout) { GstElementStateReturn ret = GST_STATE_FAILURE; GstElementState old_pending; g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE); GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "getting state"); GST_STATE_LOCK (element); /* we got an error, report immediatly */ if (GST_STATE_ERROR (element)) 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_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_SUCCESS; } else { GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "got failure"); ret = GST_STATE_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_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", gst_element_state_get_name (GST_STATE (element)), gst_element_state_get_name (GST_STATE_PENDING (element))); GST_STATE_UNLOCK (element); return ret; } /** * gst_element_get_state: * @element: a #GstElement to get the state of. * @state: a pointer to #GstElementState to hold the state. Can be NULL. * @pending: a pointer to #GstElementState 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_SUCCESS or GST_STATE_FAILURE respectively. * * Returns: GST_STATE_SUCCESS if the element has no more pending state and * the last state change succeeded, GST_STATE_ASYNC * if the element is still performing a state change or * GST_STATE_FAILURE if the last state change failed. * * MT safe. */ GstElementStateReturn gst_element_get_state (GstElement * element, GstElementState * state, GstElementState * pending, GTimeVal * timeout) { GstElementClass *oclass; GstElementStateReturn result = GST_STATE_FAILURE; g_return_val_if_fail (GST_IS_ELEMENT (element), GST_STATE_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) { GstElementState pending; g_return_if_fail (GST_IS_ELEMENT (element)); pending = GST_STATE_PENDING (element); if (pending != GST_STATE_VOID_PENDING && !GST_STATE_ERROR (element)) { GstElementState old_state = GST_STATE (element); 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) { GstElementState pending; GstMessage *message; g_return_if_fail (GST_IS_ELEMENT (element)); pending = GST_STATE_PENDING (element); if (pending != GST_STATE_VOID_PENDING) { GstElementState 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)) { GstElementState 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 #GstElementState. * * 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 #GstElementStateReturn. * * MT safe. */ GstElementStateReturn gst_element_set_state (GstElement * element, GstElementState state) { GstElementClass *oclass; GstElementState current; GstElementStateReturn return_val = GST_STATE_SUCCESS; /* get the element state lock */ GST_STATE_LOCK (element); #if 0 /* a state change is pending and we are not in error, the element is busy * with a state change and we cannot proceed. * FIXME, does not work for a bin.*/ if (G_UNLIKELY (GST_STATE_PENDING (element) != GST_STATE_VOID_PENDING && !GST_STATE_ERROR (element))) goto was_busy; #endif /* clear the error flag */ GST_STATE_ERROR (element) = FALSE; /* 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 { GstElementState 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); else return_val = GST_STATE_FAILURE; switch (return_val) { case GST_STATE_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_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_SUCCESS: GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "element changed state successfuly"); /* 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; 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_UNLOCK (element); GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "exit state change"); return return_val; /* ERROR */ #if 0 was_busy: { GST_STATE_UNLOCK (element); GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "was busy with a state change"); return GST_STATE_BUSY; } #endif invalid_return: { GST_STATE_UNLOCK (element); /* somebody added a GST_STATE_ and forgot to do stuff here ! */ g_critical ("unkown return value from a state change function"); return GST_STATE_FAILURE; } } /* is called with STATE_LOCK * * This function activates the pads of a given element. * * TODO: activate pads from src to sinks? * move pad activate logic to GstPad because we also need this * when pads are added to elements? */ static gboolean gst_element_pads_activate (GstElement * element, gboolean active) { GList *pads; gboolean result; guint32 cookie; GST_LOCK (element); restart: result = TRUE; pads = element->pads; cookie = element->pads_cookie; for (; pads && result; pads = g_list_next (pads)) { GstPad *pad = GST_PAD (pads->data); gst_object_ref (GST_OBJECT (pad)); GST_UNLOCK (element); /* we only care about real pads */ if (GST_IS_REAL_PAD (pad)) { GstRealPad *peer; gboolean pad_loop, pad_get; gboolean delay = FALSE; /* see if the pad has a loop function and grab * the peer */ GST_LOCK (pad); pad_get = GST_RPAD_GETRANGEFUNC (pad) != NULL; pad_loop = GST_RPAD_LOOPFUNC (pad) != NULL; peer = GST_RPAD_PEER (pad); if (peer) gst_object_ref (GST_OBJECT (peer)); GST_UNLOCK (pad); if (peer) { gboolean peer_loop, peer_get; /* see if the peer has a getrange function */ peer_get = GST_RPAD_GETRANGEFUNC (peer) != NULL; /* see if the peer has a loop function */ peer_loop = GST_RPAD_LOOPFUNC (peer) != NULL; /* sinkpads with a loop function are delayed since they * need the srcpad to be active first */ if (GST_PAD_IS_SINK (pad) && pad_loop && peer_get) { GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "delaying pad %s", GST_OBJECT_NAME (pad)); delay = TRUE; } else if (GST_PAD_IS_SRC (pad) && peer_loop && pad_get) { /* If the pad is a source and the peer has a loop function, * we can activate the srcpad and then the loopbased sinkpad */ GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "%sactivating pad %s", (active ? "" : "(de)"), GST_OBJECT_NAME (pad)); result &= gst_pad_set_active (pad, (active ? GST_ACTIVATE_PULL : GST_ACTIVATE_NONE)); GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "%sactivating delayed pad %s", (active ? "" : "(de)"), GST_OBJECT_NAME (peer)); result &= gst_pad_set_active (GST_PAD (peer), (active ? GST_ACTIVATE_PULL : GST_ACTIVATE_NONE)); /* set flag here since we don't want the code below to activate * the pad again */ delay = TRUE; } gst_object_unref (GST_OBJECT (peer)); } /* all other conditions are just push based pads */ if (!delay) { GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "%sactivating pad %s", (active ? "" : "(de)"), GST_OBJECT_NAME (pad)); result &= gst_pad_set_active (pad, (active ? GST_ACTIVATE_PUSH : GST_ACTIVATE_NONE)); } } gst_object_unref (GST_OBJECT (pad)); GST_LOCK (element); if (cookie != element->pads_cookie) goto restart; } GST_UNLOCK (element); return result; } /* is called with STATE_LOCK */ static GstElementStateReturn gst_element_change_state (GstElement * element) { GstElementState old_state; gint old_pending, old_transition; GstElementStateReturn result = GST_STATE_SUCCESS; g_return_val_if_fail (GST_IS_ELEMENT (element), GST_STATE_FAILURE); old_state = GST_STATE (element); old_pending = GST_STATE_PENDING (element); old_transition = GST_STATE_TRANSITION (element); /* if the element already is in the given state, we just return success */ if (old_pending == GST_STATE_VOID_PENDING || old_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 (old_state)); return GST_STATE_SUCCESS; } GST_CAT_LOG_OBJECT (GST_CAT_STATES, element, "default handler tries setting state from %s to %s (%04x)", gst_element_state_get_name (old_state), gst_element_state_get_name (old_pending), old_transition); switch (old_transition) { case GST_STATE_NULL_TO_READY: break; case GST_STATE_READY_TO_PAUSED: if (!gst_element_pads_activate (element, TRUE)) { result = GST_STATE_FAILURE; } break; case GST_STATE_PAUSED_TO_PLAYING: GST_LOCK (element); if (GST_ELEMENT_MANAGER (element)) { element->base_time = GST_ELEMENT_CAST (GST_ELEMENT_MANAGER (element))->base_time; } GST_UNLOCK (element); break; case GST_STATE_PLAYING_TO_PAUSED: break; case GST_STATE_PAUSED_TO_READY: if (!gst_element_pads_activate (element, FALSE)) { result = GST_STATE_FAILURE; } else { element->base_time = 0; } break; case GST_STATE_READY_TO_NULL: 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 (old_state), gst_element_state_get_name (old_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 (GST_OBJECT (object)); /* first we break all our links with the ouside */ while (element->pads) { gst_element_remove_pad (element, GST_PAD (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->manager, NULL); gst_object_replace ((GstObject **) & element->clock, 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; gint nspecs, 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, "name", GST_ELEMENT_NAME (element)); if (oclass->elementfactory != NULL) { GstElementFactory *factory = (GstElementFactory *) oclass->elementfactory; xmlNewChild (parent, NULL, "type", GST_PLUGIN_FEATURE (factory)->name); } /* FIXME: what is this? */ /* if (element->manager) */ /* xmlNewChild(parent, NULL, "manager", GST_ELEMENT_NAME(element->manager)); */ /* 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, "param", NULL); xmlNewChild (param, NULL, "name", 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, "value", contents); g_free (contents); g_value_unset (&value); } } 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, "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 (children->name, "param")) { xmlNodePtr child = children->xmlChildrenNode; while (child) { if (!strcmp (child->name, "name")) { name = xmlNodeGetContent (child); } else if (!strcmp (child->name, "value")) { value = 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 (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_manager_func (GstElement * element, GstPipeline * manager) { g_return_if_fail (GST_IS_ELEMENT (element)); GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, element, "setting manager to %p", manager); /* setting the manager cannot increase the refcount */ GST_LOCK (element); GST_ELEMENT_MANAGER (element) = manager; GST_UNLOCK (element); } 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); } static void gst_element_set_scheduler_func (GstElement * element, GstScheduler * scheduler) { g_return_if_fail (GST_IS_ELEMENT (element)); GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, element, "setting scheduler to %p", scheduler); GST_LOCK (element); gst_object_replace ((GstObject **) & GST_ELEMENT_SCHEDULER (element), GST_OBJECT (scheduler)); GST_UNLOCK (element); } /** * gst_element_set_manager: * @element: a #GstElement to set the manager of. * @manager: the #GstManager to set. * * Sets the manager of the element. For internal use only, unless you're * writing a new bin subclass. * * MT safe. */ void gst_element_set_manager (GstElement * element, GstPipeline * manager) { GstElementClass *oclass; g_return_if_fail (GST_IS_ELEMENT (element)); oclass = GST_ELEMENT_GET_CLASS (element); if (oclass->set_manager) oclass->set_manager (element, manager); } /** * gst_element_get_manager: * @element: a #GstElement to get the manager of. * * Returns the manager of the element. * * Returns: the element's #GstPipeline. unref after usage. * * MT safe. */ GstPipeline * gst_element_get_manager (GstElement * element) { GstPipeline *result = NULL; g_return_val_if_fail (GST_IS_ELEMENT (element), result); GST_LOCK (element); result = GST_ELEMENT_MANAGER (element); gst_object_ref (GST_OBJECT (result)); GST_UNLOCK (element); return result; } /** * 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. * * 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_UNLOCK (element); return result; } /** * gst_element_set_scheduler: * @element: a #GstElement to set the scheduler of. * @scheduler: the #GstScheduler to set. * * Sets the scheduler of the element. For internal use only, unless you're * testing elements. * * MT safe. */ void gst_element_set_scheduler (GstElement * element, GstScheduler * scheduler) { GstElementClass *oclass; g_return_if_fail (GST_IS_ELEMENT (element)); oclass = GST_ELEMENT_GET_CLASS (element); if (oclass->set_scheduler) oclass->set_scheduler (element, scheduler); } /** * gst_element_get_scheduler: * @element: a #GstElement to get the scheduler of. * * Returns the scheduler of the element. * * Returns: the element's #GstScheduler. * * MT safe. */ GstScheduler * gst_element_get_scheduler (GstElement * element) { GstScheduler *result = NULL; g_return_val_if_fail (GST_IS_ELEMENT (element), result); GST_LOCK (element); result = GST_ELEMENT_SCHEDULER (element); GST_UNLOCK (element); return result; }