/* GStreamer * Copyright (C) 1999,2000 Erik Walthinsen * 2000 Wim Taymans * 2003 Benjamin Otte * * 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. */ #include "gst_private.h" #include "gstelement.h" #include "gstregistrypool.h" #include "gstinfo.h" GST_DEBUG_CATEGORY_STATIC (element_factory_debug); #define GST_CAT_DEFAULT element_factory_debug static void gst_element_factory_class_init (GstElementFactoryClass *klass); static void gst_element_factory_init (GstElementFactory *factory); static void gst_element_factory_unload_thyself (GstPluginFeature *feature); static GstPluginFeatureClass *parent_class = NULL; /* static guint gst_element_factory_signals[LAST_SIGNAL] = { 0 }; */ GType gst_element_factory_get_type (void) { static GType elementfactory_type = 0; if (!elementfactory_type) { static const GTypeInfo elementfactory_info = { sizeof (GstElementFactoryClass), NULL, NULL, (GClassInitFunc) gst_element_factory_class_init, NULL, NULL, sizeof(GstElementFactory), 0, (GInstanceInitFunc) gst_element_factory_init, NULL }; elementfactory_type = g_type_register_static (GST_TYPE_PLUGIN_FEATURE, "GstElementFactory", &elementfactory_info, 0); GST_DEBUG_CATEGORY_INIT (element_factory_debug, "GST_ELEMENT_FACTORY", GST_DEBUG_BOLD | GST_DEBUG_FG_WHITE | GST_DEBUG_BG_RED, "element factories keep information about installed elements"); } return elementfactory_type; } static void gst_element_factory_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_peek_parent (klass); gstpluginfeature_class->unload_thyself = GST_DEBUG_FUNCPTR (gst_element_factory_unload_thyself); } static void gst_element_factory_init (GstElementFactory *factory) { factory->padtemplates = NULL; factory->numpadtemplates = 0; } /** * gst_element_factory_find: * @name: name of factory to find * * Search for an element factory of the given name. * * Returns: #GstElementFactory if found, NULL otherwise */ GstElementFactory* gst_element_factory_find (const gchar *name) { GstPluginFeature *feature; g_return_val_if_fail(name != NULL, NULL); feature = gst_registry_pool_find_feature (name, GST_TYPE_ELEMENT_FACTORY); if (feature) return GST_ELEMENT_FACTORY (feature); /* this should be an ERROR */ GST_DEBUG ("no such elementfactory \"%s\"", name); return NULL; } void __gst_element_details_clear (GstElementDetails *dp) { g_free (dp->longname); dp->longname = NULL; g_free (dp->klass); dp->klass = NULL; g_free (dp->description); dp->description = NULL; g_free (dp->author); dp->author = NULL; } void __gst_element_details_set (GstElementDetails *dest, const GstElementDetails *src) { dest->longname = g_strdup (src->longname); dest->klass = g_strdup (src->klass); dest->description = g_strdup (src->description); dest->author = g_strdup (src->author); } void __gst_element_details_copy (GstElementDetails *dest, const GstElementDetails *src) { __gst_element_details_clear (dest); __gst_element_details_set (dest, src); } static void gst_element_factory_cleanup (GstElementFactory *factory) { __gst_element_details_clear (&factory->details); if (factory->type) { g_type_class_unref (g_type_class_peek (factory->type)); factory->type = 0; } g_list_foreach (factory->padtemplates, (GFunc) g_object_unref, NULL); g_list_free (factory->padtemplates); factory->padtemplates = NULL; factory->numpadtemplates = 0; } /** * gst_element_register: * @plugin: * @name: name of elements of this type * @rank: rank of element (higher rank means more importance when autoplugging) * @type: GType of element to register * * Create a new elementfactory capable of insantiating objects of the * given type. * * Returns: TRUE, if the registering succeeded, FALSE on error */ gboolean gst_element_register (GstPlugin *plugin, const gchar *name, guint rank, GType type) { GstElementFactory *factory; GstElementClass *klass; g_return_val_if_fail (name != NULL, FALSE); g_return_val_if_fail (g_type_is_a (type, GST_TYPE_ELEMENT), FALSE); factory = gst_element_factory_find (name); if (!factory) { klass = GST_ELEMENT_CLASS (g_type_class_ref (type)); factory = GST_ELEMENT_FACTORY (g_object_new (GST_TYPE_ELEMENT_FACTORY, NULL)); gst_plugin_feature_set_name (GST_PLUGIN_FEATURE (factory), name); GST_LOG_OBJECT (factory, "Created new elementfactory for type %s", g_type_name (type)); } else { g_return_val_if_fail (factory->type == 0, FALSE); klass = GST_ELEMENT_CLASS (g_type_class_ref (type)); gst_element_factory_cleanup (factory); GST_LOG_OBJECT (factory, "Reuse existing elementfactory for type %s", g_type_name (type)); } factory->type = type; __gst_element_details_copy (&factory->details, &klass->details); factory->padtemplates = g_list_copy (klass->padtemplates); g_list_foreach (factory->padtemplates, (GFunc) g_object_ref, NULL); factory->numpadtemplates = klass->numpadtemplates; gst_plugin_feature_set_rank (GST_PLUGIN_FEATURE (factory), rank); gst_plugin_add_feature (plugin, GST_PLUGIN_FEATURE (factory)); return TRUE; } /** * gst_element_factory_create: * @factory: factory to instantiate * @name: name of new element * * Create a new element of the type defined by the given elementfactory. * It will be given the name supplied, since all elements require a name as * their first argument. * * Returns: new #GstElement or NULL if the element couldn't be created */ GstElement* gst_element_factory_create (GstElementFactory *factory, const gchar *name) { GstElement *element; g_return_val_if_fail (factory != NULL, NULL); if (!gst_plugin_feature_ensure_loaded (GST_PLUGIN_FEATURE (factory))) { GST_INFO ("could not load element factory for element \"%s\"", name); return NULL; } GST_LOG_OBJECT (factory, "creating element (name \"%s\", type %d)", GST_STR_NULL (name), (gint) factory->type); if (factory->type == 0) { g_critical ("Factory for `%s' has no type", GST_PLUGIN_FEATURE_NAME (factory)); return NULL; } /* create an instance of the element */ element = GST_ELEMENT (g_object_new (factory->type, NULL)); g_assert (element != NULL); gst_object_set_name (GST_OBJECT (element), name); return element; } /** * gst_element_factory_make: * @factoryname: a named factory to instantiate * @name: name of new element * * Create a new element of the type defined by the given element factory. * If name is NULL, then the element will receive a guaranteed unique name, * consisting of the element factory name and a number. * If name is given, it will be given the name supplied. * * Returns: new #GstElement or NULL if unable to create element */ GstElement* gst_element_factory_make (const gchar *factoryname, const gchar *name) { GstElementFactory *factory; GstElement *element; g_return_val_if_fail (factoryname != NULL, NULL); GST_LOG ("gstelementfactory: make \"%s\" \"%s\"", factoryname, GST_STR_NULL (name)); /* gst_plugin_load_element_factory (factoryname); */ factory = gst_element_factory_find (factoryname); if (factory == NULL) { GST_INFO ("no such element factory \"%s\"!", factoryname); return NULL; } element = gst_element_factory_create (factory, name); if (element == NULL) { GST_INFO_OBJECT (factory, "couldn't create instance!"); return NULL; } return element; } void __gst_element_factory_add_pad_template (GstElementFactory *factory, GstPadTemplate *templ) { g_return_if_fail (factory != NULL); g_return_if_fail (templ != NULL); gst_object_ref (GST_OBJECT (templ)); gst_object_sink (GST_OBJECT (templ)); factory->padtemplates = g_list_append (factory->padtemplates, templ); factory->numpadtemplates++; } /** * gst_element_factory_get_element_type: * @factory: factory to get managed #GType from * * Get the #GType for elements managed by this factory * * Returns: the #GType for elements managed by this factory */ GType gst_element_factory_get_element_type (GstElementFactory *factory) { g_return_val_if_fail (GST_IS_ELEMENT_FACTORY (factory), 0); return factory->type; } /** * gst_element_factory_get_longname: * @factory: a #GstElementFactory * * Gets the longname for this factory * * Returns: the longname */ G_CONST_RETURN gchar * gst_element_factory_get_longname (GstElementFactory *factory) { g_return_val_if_fail (GST_IS_ELEMENT_FACTORY (factory), NULL); return factory->details.longname; } /** * gst_element_factory_get_class: * @factory: a #GstElementFactory * * Gets the class for this factory. * * Returns: the class */ G_CONST_RETURN gchar * gst_element_factory_get_class (GstElementFactory *factory) { g_return_val_if_fail (GST_IS_ELEMENT_FACTORY (factory), NULL); return factory->details.klass; } /** * gst_element_factory_get_description: * @factory: a #GstElementFactory * * Gets the description for this factory. * * Returns: the description */ G_CONST_RETURN gchar * gst_element_factory_get_description (GstElementFactory *factory) { g_return_val_if_fail (GST_IS_ELEMENT_FACTORY (factory), NULL); return factory->details.description; } /** * gst_element_factory_get_author: * @factory: a #GstElementFactory * * Gets the author for this factory. * * Returns: the author */ G_CONST_RETURN gchar * gst_element_factory_get_author (GstElementFactory *factory) { g_return_val_if_fail (GST_IS_ELEMENT_FACTORY (factory), NULL); return factory->details.author; } /** * gst_element_factory_get_num_padtemplates: * @factory: a #GstElementFactory * * Gets the number of padtemplates in this factory. * * Returns: the number of padtemplates */ guint gst_element_factory_get_num_padtemplates (GstElementFactory *factory) { g_return_val_if_fail (GST_IS_ELEMENT_FACTORY (factory), 0); return factory->numpadtemplates; } /** * gst_element_factory_get_padtemplates: * @factory: a #GstElementFactory * * Gets the #Glist of padtemplates for this factory. * * Returns: the padtemplates */ G_CONST_RETURN GList * gst_element_factory_get_padtemplates (GstElementFactory *factory) { g_return_val_if_fail (GST_IS_ELEMENT_FACTORY (factory), NULL); return factory->padtemplates; } /** * gst_element_factory_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_element_factory_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_is_always_compatible (GST_PAD_TEMPLATE_CAPS (template), caps)) return TRUE; } templates = g_list_next (templates); } return FALSE; } /** * gst_element_factory_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_element_factory_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_is_always_compatible (caps, GST_PAD_TEMPLATE_CAPS (template))) return TRUE; } templates = g_list_next (templates); } return FALSE; } static void gst_element_factory_unload_thyself (GstPluginFeature *feature) { GstElementFactory *factory; factory = GST_ELEMENT_FACTORY (feature); if (factory->type) { g_type_class_unref (g_type_class_peek (factory->type)); factory->type = 0; } }