/* GStreamer * Copyright (C) 1999,2000 Erik Walthinsen * 2000 Wim Taymans * * gstelementfactory.c: GstElementFactory object, support routines * * 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. */ /* #define DEBUG_ENABLED */ #include "gst_private.h" #include "gstelement.h" static void gst_elementfactory_class_init (GstElementFactoryClass *klass); static void gst_elementfactory_init (GstElementFactory *factory); #ifndef GST_DISABLE_REGISTRY static void gst_elementfactory_restore_thyself (GstObject *object, xmlNodePtr parent); static xmlNodePtr gst_elementfactory_save_thyself (GstObject *object, xmlNodePtr parent); #endif static void gst_elementfactory_unload_thyself (GstPluginFeature *feature); /* global list of registered elementfactories */ static GList* _gst_elementfactories; static GstPluginFeatureClass *parent_class = NULL; /* static guint gst_elementfactory_signals[LAST_SIGNAL] = { 0 }; */ GType gst_elementfactory_get_type (void) { static GType elementfactory_type = 0; if (!elementfactory_type) { static const GTypeInfo elementfactory_info = { sizeof (GstElementFactoryClass), NULL, NULL, (GClassInitFunc) gst_elementfactory_class_init, NULL, NULL, sizeof(GstElementFactory), 0, (GInstanceInitFunc) gst_elementfactory_init, NULL }; elementfactory_type = g_type_register_static (GST_TYPE_PLUGIN_FEATURE, "GstElementFactory", &elementfactory_info, 0); } return elementfactory_type; } static void gst_elementfactory_class_init (GstElementFactoryClass *klass) { GObjectClass *gobject_class; GstObjectClass *gstobject_class; GstPluginFeatureClass *gstpluginfeature_class; gobject_class = (GObjectClass*)klass; gstobject_class = (GstObjectClass*)klass; gstpluginfeature_class = (GstPluginFeatureClass*) klass; parent_class = g_type_class_ref (GST_TYPE_PLUGIN_FEATURE); #ifndef GST_DISABLE_REGISTRY gstobject_class->save_thyself = GST_DEBUG_FUNCPTR (gst_elementfactory_save_thyself); gstobject_class->restore_thyself = GST_DEBUG_FUNCPTR (gst_elementfactory_restore_thyself); #endif gstpluginfeature_class->unload_thyself = GST_DEBUG_FUNCPTR (gst_elementfactory_unload_thyself); _gst_elementfactories = NULL; } static void gst_elementfactory_init (GstElementFactory *factory) { factory->padtemplates = NULL; factory->numpadtemplates = 0; _gst_elementfactories = g_list_prepend (_gst_elementfactories, factory); } /** * gst_elementfactory_find: * @name: name of factory to find * * Search for an elementfactory of the given name. * * Returns: #GstElementFactory if found, NULL otherwise */ GstElementFactory* gst_elementfactory_find (const gchar *name) { GList *walk; GstElementFactory *factory; g_return_val_if_fail(name != NULL, NULL); walk = _gst_elementfactories; while (walk) { factory = (GstElementFactory *)(walk->data); if (!strcmp(name, GST_OBJECT_NAME (factory))) return factory; walk = g_list_next(walk); } /* this should be an ERROR */ GST_DEBUG (GST_CAT_ELEMENTFACTORY,"no such elementfactory \"%s\"", name); return NULL; } /** * gst_elementfactory_get_list: * * Get the global list of elementfactories. * * Returns: GList of type #GstElementFactory */ const GList* gst_elementfactory_get_list (void) { return _gst_elementfactories; } static void gst_element_details_free (GstElementDetails *dp) { g_return_if_fail (dp); if (dp->longname) g_free (dp->longname); if (dp->klass) g_free (dp->klass); if (dp->description) g_free (dp->description); if (dp->version) g_free (dp->version); if (dp->author) g_free (dp->author); if (dp->copyright) g_free (dp->copyright); g_free (dp); } /** * gst_elementfactory_new: * @name: name of new elementfactory * @type: GType of new element * @details: #GstElementDetails structure with element details * * Create a new elementfactory capable of insantiating objects of the * given type. * * Returns: new elementfactory */ GstElementFactory* gst_elementfactory_new (const gchar *name, GType type, GstElementDetails *details) { GstElementFactory *factory; g_return_val_if_fail(name != NULL, NULL); g_return_val_if_fail (type, NULL); g_return_val_if_fail (details, NULL); factory = gst_elementfactory_find (name); if (!factory) factory = GST_ELEMENTFACTORY (g_object_new (GST_TYPE_ELEMENTFACTORY, NULL)); if (factory->details_dynamic) { gst_element_details_free (factory->details); factory->details_dynamic = FALSE; } factory->details = details; if (!factory->type) factory->type = type; else if (factory->type != type) g_critical ("`%s' requested type change (!)", name); gst_object_set_name (GST_OBJECT (factory), name); return factory; } /** * gst_elementfactory_create: * @factory: factory to instantiate * @name: name of new element * * Create a new element of the type defined by the given elementfactory. * It wll be given the name supplied, since all elements require a name as * their first argument. * * Returns: new #GstElement */ GstElement * gst_elementfactory_create (GstElementFactory *factory, const gchar *name) { GstElement *element; GstElementClass *oclass; g_return_val_if_fail(factory != NULL, NULL); GST_DEBUG (GST_CAT_ELEMENTFACTORY,"creating element from factory \"%s\" with name \"%s\" and type %d", GST_OBJECT_NAME (factory), name, (gint) factory->type); if (!gst_plugin_feature_ensure_loaded (GST_PLUGIN_FEATURE (factory))) return NULL; if (factory->type == 0) { g_critical ("Factory for `%s' has no type", gst_object_get_name (GST_OBJECT (factory))); return NULL; } /* create an instance of the element */ element = GST_ELEMENT(g_object_new(factory->type,NULL)); g_assert(element != NULL); /* attempt to set the elemenfactory class pointer if necessary */ oclass = GST_ELEMENT_CLASS(G_OBJECT_GET_CLASS(element)); if (oclass->elementfactory == NULL) { GST_DEBUG (GST_CAT_ELEMENTFACTORY,"class %s", GST_OBJECT_NAME (factory)); oclass->elementfactory = factory; /* copy pad template pointers to the element class, allow for custom padtemplates */ oclass->padtemplates = g_list_concat (oclass->padtemplates, factory->padtemplates); oclass->numpadtemplates += factory->numpadtemplates; } gst_object_set_name (GST_OBJECT (element),name); return element; } /** * gst_elementfactory_make: * @factoryname: a named factory to instantiate * @name: name of new element * * Create a new element of the type defined by the given elementfactory. * It wll be given the name supplied, since all elements require a name as * their first argument. * * Returns: new #GstElement (or NULL if unable to create element) */ GstElement* gst_elementfactory_make (const gchar *factoryname, const gchar *name) { GstElementFactory *factory; GstElement *element; g_return_val_if_fail (factoryname != NULL, NULL); GST_DEBUG (GST_CAT_ELEMENTFACTORY, "gstelementfactory: make \"%s\" \"%s\"", factoryname, name); /* gst_plugin_load_elementfactory(factoryname); */ factory = gst_elementfactory_find(factoryname); if (factory == NULL) { GST_INFO (GST_CAT_ELEMENTFACTORY,"no such elementfactory \"%s\"!",factoryname); return NULL; } element = gst_elementfactory_create(factory,name); if (element == NULL) { GST_INFO (GST_CAT_ELEMENTFACTORY,"couldn't create instance of elementfactory \"%s\"!",factoryname); return NULL; } return element; } /** * gst_elementfactory_add_padtemplate : * @elementfactory: factory to add the src id to * @templ: the padtemplate to add * * Add the given padtemplate to this elementfactory. */ void gst_elementfactory_add_padtemplate (GstElementFactory *factory, GstPadTemplate *templ) { GList *padtemplates; g_return_if_fail(factory != NULL); g_return_if_fail(templ != NULL); padtemplates = factory->padtemplates; gst_object_ref (GST_OBJECT (templ)); while (padtemplates) { GstPadTemplate *oldtempl = GST_PADTEMPLATE (padtemplates->data); if (!strcmp (oldtempl->name_template, templ->name_template)) { gst_object_unref (GST_OBJECT (oldtempl)); padtemplates->data = templ; return; } padtemplates = g_list_next (padtemplates); } factory->padtemplates = g_list_append (factory->padtemplates, templ); factory->numpadtemplates++; } /** * gst_elementfactory_can_src_caps : * @factory: factory to query * @caps: the caps to check * * Checks if the factory can source the given capability. * * Returns: true if it can src the capabilities */ gboolean gst_elementfactory_can_src_caps (GstElementFactory *factory, GstCaps *caps) { GList *templates; g_return_val_if_fail(factory != NULL, FALSE); g_return_val_if_fail(caps != NULL, FALSE); templates = factory->padtemplates; while (templates) { GstPadTemplate *template = (GstPadTemplate *)templates->data; if (template->direction == GST_PAD_SRC) { if (gst_caps_check_compatibility (GST_PADTEMPLATE_CAPS (template), caps)) return TRUE; } templates = g_list_next (templates); } return FALSE; } /** * gst_elementfactory_can_sink_caps : * @factory: factory to query * @caps: the caps to check * * Checks if the factory can sink the given capability. * * Returns: true if it can sink the capabilities */ gboolean gst_elementfactory_can_sink_caps (GstElementFactory *factory, GstCaps *caps) { GList *templates; g_return_val_if_fail(factory != NULL, FALSE); g_return_val_if_fail(caps != NULL, FALSE); templates = factory->padtemplates; while (templates) { GstPadTemplate *template = (GstPadTemplate *)templates->data; if (template->direction == GST_PAD_SINK) { if (gst_caps_check_compatibility (caps, GST_PADTEMPLATE_CAPS (template))) return TRUE; } templates = g_list_next (templates); } return FALSE; } static void gst_elementfactory_unload_thyself (GstPluginFeature *feature) { GstElementFactory *factory; factory = GST_ELEMENTFACTORY (feature); factory->type = 0; } #ifndef GST_DISABLE_REGISTRY static xmlNodePtr gst_elementfactory_save_thyself (GstObject *object, xmlNodePtr parent) { GList *pads; GstElementFactory *factory; factory = GST_ELEMENTFACTORY (object); if (GST_OBJECT_CLASS (parent_class)->save_thyself) { GST_OBJECT_CLASS (parent_class)->save_thyself (object, parent); } g_return_val_if_fail(factory != NULL, NULL); if (factory->details) { xmlNewChild(parent,NULL,"longname", factory->details->longname); xmlNewChild(parent,NULL,"class", factory->details->klass); xmlNewChild(parent,NULL,"description", factory->details->description); xmlNewChild(parent,NULL,"version", factory->details->version); xmlNewChild(parent,NULL,"author", factory->details->author); xmlNewChild(parent,NULL,"copyright", factory->details->copyright); } else g_warning ("elementfactory `%s' is missing details", object->name); pads = factory->padtemplates; if (pads) { while (pads) { xmlNodePtr subtree; GstPadTemplate *padtemplate = (GstPadTemplate *)pads->data; subtree = xmlNewChild(parent, NULL, "padtemplate", NULL); gst_padtemplate_save_thyself(padtemplate, subtree); pads = g_list_next (pads); } } return parent; } static void gst_elementfactory_restore_thyself (GstObject *object, xmlNodePtr parent) { GstElementFactory *factory = GST_ELEMENTFACTORY (object); xmlNodePtr children = parent->xmlChildrenNode; factory->details_dynamic = TRUE; factory->details = g_new0(GstElementDetails, 1); factory->padtemplates = NULL; if (GST_OBJECT_CLASS (parent_class)->restore_thyself) { GST_OBJECT_CLASS (parent_class)->restore_thyself (object, parent); } while (children) { if (!strcmp(children->name, "longname")) { factory->details->longname = xmlNodeGetContent(children); } if (!strcmp(children->name, "class")) { factory->details->klass = xmlNodeGetContent(children); } if (!strcmp(children->name, "description")) { factory->details->description = xmlNodeGetContent(children); } if (!strcmp(children->name, "version")) { factory->details->version = xmlNodeGetContent(children); } if (!strcmp(children->name, "author")) { factory->details->author = xmlNodeGetContent(children); } if (!strcmp(children->name, "copyright")) { factory->details->copyright = xmlNodeGetContent(children); } if (!strcmp(children->name, "padtemplate")) { GstPadTemplate *template; template = gst_padtemplate_load_thyself (children); gst_elementfactory_add_padtemplate (factory, template); } children = children->next; } } #endif /* GST_DISABLE_REGISTRY */