diff -r 000000000000 -r 0e761a78d257 gstreamer_core/gst/gstelementfactory.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/gstreamer_core/gst/gstelementfactory.c Thu Dec 17 08:53:32 2009 +0200 @@ -0,0 +1,781 @@ +/* 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. + */ + +/** + * SECTION:gstelementfactory + * @short_description: Create GstElements from a factory + * @see_also: #GstElement, #GstPlugin, #GstPluginFeature, #GstPadTemplate. + * + * #GstElementFactory is used to create instances of elements. A + * GstElementfactory can be added to a #GstPlugin as it is also a + * #GstPluginFeature. + * + * Use the gst_element_factory_find() and gst_element_factory_create() + * functions to create element instances or use gst_element_factory_make() as a + * convenient shortcut. + * + * The following code example shows you how to create a GstFileSrc element. + * + * + * Using an element factory + * + * #include <gst/gst.h> + * GstElement *src; + * GstElementFactory *srcfactory; + * gst_init(&argc,&argv); + * srcfactory = gst_element_factory_find("filesrc"); + * g_return_if_fail(srcfactory != NULL); + * src = gst_element_factory_create(srcfactory,"src"); + * g_return_if_fail(src != NULL); + * ... + * + * + * + * Last reviewed on 2005-11-23 (0.9.5) + */ + +#include "gst_private.h" + +#include "gstelement.h" +#include "gstinfo.h" +#include "gsturi.h" +#include "gstregistry.h" + +#include "glib-compat-private.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_finalize (GObject * object); +void __gst_element_details_clear (GstElementDetails * dp); +static void gst_element_factory_cleanup (GstElementFactory * factory); + +static GstPluginFeatureClass *parent_class = NULL; + +/* static guint gst_element_factory_signals[LAST_SIGNAL] = { 0 }; */ +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + + +GType +gst_element_factory_get_type (void) +{ + static GType elementfactory_type = 0; + + if (G_UNLIKELY (elementfactory_type == 0)) { + 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); + + gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_element_factory_finalize); +} + +static void +gst_element_factory_init (GstElementFactory * factory) +{ + factory->staticpadtemplates = NULL; + factory->numpadtemplates = 0; + + factory->uri_type = GST_URI_UNKNOWN; + factory->uri_protocols = NULL; + + factory->interfaces = NULL; +} + +static void +gst_element_factory_finalize (GObject * object) +{ + GstElementFactory *factory = GST_ELEMENT_FACTORY (object); + + gst_element_factory_cleanup (factory); + G_OBJECT_CLASS (parent_class)->finalize (object); +} + +/** + * gst_element_factory_find: + * @name: name of factory to find + * + * Search for an element factory of the given name. Refs the returned + * element factory; caller is responsible for unreffing. + * + * Returns: #GstElementFactory if found, NULL otherwise + */ +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + +GstElementFactory * +gst_element_factory_find (const gchar * name) +{ + GstPluginFeature *feature; + + g_return_val_if_fail (name != NULL, NULL); + + feature = gst_registry_find_feature (gst_registry_get_default (), name, + GST_TYPE_ELEMENT_FACTORY); + if (feature) + return GST_ELEMENT_FACTORY (feature); + + /* this isn't an error, for instance when you query if an element factory is + * present */ + GST_LOG ("no such element factory \"%s\"", name); + return NULL; +} +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + + +void +__gst_element_details_clear (GstElementDetails * dp) +{ + g_free (dp->longname); + g_free (dp->klass); + g_free (dp->description); + g_free (dp->author); + memset (dp, 0, sizeof (GstElementDetails)); +} + +#define VALIDATE_SET(__dest, __src, __entry) \ +G_STMT_START { \ + if (g_utf8_validate (__src->__entry, -1, NULL)) { \ + __dest->__entry = g_strdup (__src->__entry); \ + } else { \ + g_warning ("Invalid UTF-8 in " G_STRINGIFY (__entry) ": %s", \ + __src->__entry); \ + __dest->__entry = g_strdup ("[ERROR: invalid UTF-8]"); \ + } \ +} G_STMT_END + +#ifdef __SYMBIAN32__ +EXPORT_C +#endif +void +__gst_element_details_set (GstElementDetails * dest, + const GstElementDetails * src) +{ + VALIDATE_SET (dest, src, longname); + VALIDATE_SET (dest, src, klass); + VALIDATE_SET (dest, src, description); + VALIDATE_SET (dest, src, author); +} +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + + +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) +{ + GList *item; + + __gst_element_details_clear (&factory->details); + if (factory->type) { + g_type_class_unref (g_type_class_peek (factory->type)); + factory->type = 0; + } + + for (item = factory->staticpadtemplates; item; item = item->next) { + GstStaticPadTemplate *templ = item->data; + GstCaps *caps = (GstCaps *) & (templ->static_caps); + + g_free ((gchar *) templ->static_caps.string); + + /* FIXME: this is not threadsafe */ + if (caps->refcount == 1) { + GstStructure *structure; + guint i; + + for (i = 0; i < caps->structs->len; i++) { + structure = (GstStructure *) gst_caps_get_structure (caps, i); + gst_structure_set_parent_refcount (structure, NULL); + gst_structure_free (structure); + } + g_ptr_array_free (caps->structs, TRUE); + caps->refcount = 0; + } + g_free (templ); + } + g_list_free (factory->staticpadtemplates); + factory->staticpadtemplates = NULL; + factory->numpadtemplates = 0; + factory->uri_type = GST_URI_UNKNOWN; + if (factory->uri_protocols) { + g_strfreev (factory->uri_protocols); + factory->uri_protocols = NULL; + } + + g_list_foreach (factory->interfaces, (GFunc) g_free, NULL); + g_list_free (factory->interfaces); + factory->interfaces = NULL; +} + +/** + * gst_element_register: + * @plugin: #GstPlugin to register the element with, or NULL for a static + * element (note that passing NULL only works in GStreamer 0.10.13 and later) + * @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 instantiating objects of the + * @type and add the factory to @plugin. + * + * Returns: TRUE, if the registering succeeded, FALSE on error + */ +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + +gboolean +gst_element_register (GstPlugin * plugin, const gchar * name, guint rank, + GType type) +{ + GstElementFactory *factory; + GType *interfaces; + guint n_interfaces, i; + GstElementClass *klass; + GList *item; + + 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 (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)); + + klass = GST_ELEMENT_CLASS (g_type_class_ref (type)); + if ((klass->details.longname == NULL) || + (klass->details.klass == NULL) || (klass->details.author == NULL)) + goto detailserror; + + factory->type = type; + __gst_element_details_copy (&factory->details, &klass->details); + for (item = klass->padtemplates; item; item = item->next) { + GstPadTemplate *templ = item->data; + GstStaticPadTemplate *newt; + + newt = g_new0 (GstStaticPadTemplate, 1); + newt->name_template = g_intern_string (templ->name_template); + newt->direction = templ->direction; + newt->presence = templ->presence; + newt->static_caps.string = gst_caps_to_string (templ->caps); + factory->staticpadtemplates = + g_list_append (factory->staticpadtemplates, newt); + } + factory->numpadtemplates = klass->numpadtemplates; + klass->elementfactory = factory; + + /* special stuff for URI handling */ + if (g_type_is_a (type, GST_TYPE_URI_HANDLER)) { + GstURIHandlerInterface *iface = (GstURIHandlerInterface *) + g_type_interface_peek (klass, GST_TYPE_URI_HANDLER); + + if (!iface || (!iface->get_type && !iface->get_type_full) || + (!iface->get_protocols && !iface->get_protocols_full)) + goto urierror; + if (iface->get_type) + factory->uri_type = iface->get_type (); + else if (iface->get_type_full) + factory->uri_type = iface->get_type_full (factory->type); + if (!GST_URI_TYPE_IS_VALID (factory->uri_type)) + goto urierror; + if (iface->get_protocols) + factory->uri_protocols = g_strdupv (iface->get_protocols ()); + else if (iface->get_protocols_full) + factory->uri_protocols = iface->get_protocols_full (factory->type); + if (!factory->uri_protocols) + goto urierror; + } + + interfaces = g_type_interfaces (type, &n_interfaces); + for (i = 0; i < n_interfaces; i++) { + __gst_element_factory_add_interface (factory, g_type_name (interfaces[i])); + } + g_free (interfaces); + + if (plugin && plugin->desc.name) { + GST_PLUGIN_FEATURE (factory)->plugin_name = plugin->desc.name; + } else { + GST_PLUGIN_FEATURE (factory)->plugin_name = "NULL"; + } + gst_plugin_feature_set_rank (GST_PLUGIN_FEATURE (factory), rank); + GST_PLUGIN_FEATURE (factory)->loaded = TRUE; + + gst_registry_add_feature (gst_registry_get_default (), + GST_PLUGIN_FEATURE (factory)); + + return TRUE; + + /* ERRORS */ +urierror: + { + GST_WARNING_OBJECT (factory, "error with uri handler!"); + gst_element_factory_cleanup (factory); + return FALSE; + } + +detailserror: + { + GST_WARNING_OBJECT (factory, + "The GstElementDetails don't seem to have been set properly"); + gst_element_factory_cleanup (factory); + return FALSE; + } +} + +/** + * 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 + */ +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + +GstElement * +gst_element_factory_create (GstElementFactory * factory, const gchar * name) +{ + GstElement *element; + GstElementClass *oclass; + GstElementFactory *newfactory; + + g_return_val_if_fail (factory != NULL, NULL); + + newfactory = + GST_ELEMENT_FACTORY (gst_plugin_feature_load (GST_PLUGIN_FEATURE + (factory))); + + if (newfactory == NULL) + goto load_failed; + + factory = newfactory; + + if (name) + GST_INFO ("creating element \"%s\" named \"%s\"", + GST_PLUGIN_FEATURE_NAME (factory), GST_STR_NULL (name)); + else + GST_INFO ("creating element \"%s\"", GST_PLUGIN_FEATURE_NAME (factory)); + + if (factory->type == 0) + goto no_type; + + /* create an instance of the element, cast so we don't assert on NULL */ + element = GST_ELEMENT_CAST (g_object_new (factory->type, NULL)); + if (G_UNLIKELY (element == NULL)) + goto no_element; + + /* fill in the pointer to the factory in the element class. The + * class will not be unreffed currently. + * FIXME: This isn't safe and may leak a refcount on the factory if 2 threads + * create the first instance of an element at the same moment */ + oclass = GST_ELEMENT_GET_CLASS (element); + if (G_UNLIKELY (oclass->elementfactory == NULL)) + oclass->elementfactory = factory; + else + gst_object_unref (factory); + + if (name) + gst_object_set_name (GST_OBJECT (element), name); + + GST_DEBUG ("created element \"%s\"", GST_PLUGIN_FEATURE_NAME (factory)); + + return element; + + /* ERRORS */ +load_failed: + { + GST_WARNING_OBJECT (factory, "loading plugin returned NULL!"); + return NULL; + } +no_type: + { + GST_WARNING_OBJECT (factory, "factory has no type"); + gst_object_unref (factory); + return NULL; + } +no_element: + { + GST_WARNING_OBJECT (factory, "could not create element"); + gst_object_unref (factory); + return NULL; + } +} + +/** + * 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 + */ +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + +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)); + + factory = gst_element_factory_find (factoryname); + if (factory == NULL) + goto no_factory; + + GST_LOG_OBJECT (factory, "found factory %p", factory); + element = gst_element_factory_create (factory, name); + gst_object_unref (factory); + if (element == NULL) + goto create_failed; + + return element; + + /* ERRORS */ +no_factory: + { + GST_INFO ("no such element factory \"%s\"!", factoryname); + return NULL; + } +create_failed: + { + GST_INFO_OBJECT (factory, "couldn't create instance!"); + return NULL; + } +} +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + + +void +__gst_element_factory_add_static_pad_template (GstElementFactory * factory, + GstStaticPadTemplate * templ) +{ + g_return_if_fail (factory != NULL); + g_return_if_fail (templ != NULL); + + factory->staticpadtemplates = + g_list_append (factory->staticpadtemplates, 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. The type can + * only be retrieved if the element factory is loaded, which can be + * assured with gst_plugin_feature_load(). + * + * Returns: the #GType for elements managed by this factory or 0 if + * the factory is not loaded. + */ +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + +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 + */ +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + +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_klass: + * @factory: a #GstElementFactory + * + * Gets the class for this factory. + * + * Returns: the class + */ +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + +G_CONST_RETURN gchar * +gst_element_factory_get_klass (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 + */ +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + +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 + */ +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + +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_pad_templates: + * @factory: a #GstElementFactory + * + * Gets the number of pad_templates in this factory. + * + * Returns: the number of pad_templates + */ +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + +guint +gst_element_factory_get_num_pad_templates (GstElementFactory * factory) +{ + g_return_val_if_fail (GST_IS_ELEMENT_FACTORY (factory), 0); + + return factory->numpadtemplates; +} + +/** + * __gst_element_factory_add_interface: + * @elementfactory: The elementfactory to add the interface to + * @interfacename: Name of the interface + * + * Adds the given interfacename to the list of implemented interfaces of the + * element. + */ +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + +void +__gst_element_factory_add_interface (GstElementFactory * elementfactory, + const gchar * interfacename) +{ + g_return_if_fail (GST_IS_ELEMENT_FACTORY (elementfactory)); + g_return_if_fail (interfacename != NULL); + g_return_if_fail (interfacename[0] != '\0'); /* no empty string */ + + elementfactory->interfaces = + g_list_prepend (elementfactory->interfaces, g_strdup (interfacename)); +} + +/** + * gst_element_factory_get_static_pad_templates: + * @factory: a #GstElementFactory + * + * Gets the #GList of #GstStaticPadTemplate for this factory. + * + * Returns: the padtemplates + */ +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + +G_CONST_RETURN GList * +gst_element_factory_get_static_pad_templates (GstElementFactory * factory) +{ + g_return_val_if_fail (GST_IS_ELEMENT_FACTORY (factory), NULL); + + return factory->staticpadtemplates; +} + +/** + * gst_element_factory_get_uri_type: + * @factory: a #GstElementFactory + * + * Gets the type of URIs the element supports or GST_URI_UNKNOWN if none. + * + * Returns: type of URIs this element supports + */ +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + +gint +gst_element_factory_get_uri_type (GstElementFactory * factory) +{ + g_return_val_if_fail (GST_IS_ELEMENT_FACTORY (factory), GST_URI_UNKNOWN); + + return factory->uri_type; +} + +/** + * gst_element_factory_get_uri_protocols: + * @factory: a #GstElementFactory + * + * Gets a NULL-terminated array of protocols this element supports or NULL if + * no protocols are supported. You may not change the contents of the returned + * array, as it is still owned by the element factory. Use g_strdupv() to + * make a copy of the protocol string array if you need to. + * + * Returns: the supported protocols or NULL + */ +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + +gchar ** +gst_element_factory_get_uri_protocols (GstElementFactory * factory) +{ + g_return_val_if_fail (GST_IS_ELEMENT_FACTORY (factory), NULL); + + return factory->uri_protocols; +} + +/** + * gst_element_factory_has_interface: + * @factory: a #GstElementFactory + * @interfacename: an interface name + * + * Check if @factory implements the interface with name @interfacename. + * + * Returns: #TRUE when @factory implement the interface. + * + * Since: 0.10.14 + */ +#ifdef __SYMBIAN32__ +EXPORT_C +#endif + +gboolean +gst_element_factory_has_interface (GstElementFactory * factory, + const gchar * interfacename) +{ + GList *walk; + + g_return_val_if_fail (GST_IS_ELEMENT_FACTORY (factory), FALSE); + + for (walk = factory->interfaces; walk; walk = g_list_next (walk)) { + gchar *iname = (gchar *) walk->data; + + if (!strcmp (iname, interfacename)) + return TRUE; + } + return FALSE; +}