/* GStreamer * Copyright (C) 1999,2000 Erik Walthinsen * 2000 Wim Taymans * * gstplugin.c: Plugin subsystem for loading elements, types, and libs * * 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:gstplugin * @short_description: Container for features loaded from a shared object module * @see_also: #GstPluginFeature, #GstElementFactory * * GStreamer is extensible, so #GstElement instances can be loaded at runtime. * A plugin system can provide one or more of the basic * GStreamer #GstPluginFeature subclasses. * * A plugin should export a symbol gst_plugin_desc that is a * struct of type #GstPluginDesc. * the plugin loader will check the version of the core library the plugin was * linked against and will create a new #GstPlugin. It will then call the * #GstPluginInitFunc function that was provided in the * gst_plugin_desc. * * Once you have a handle to a #GstPlugin (e.g. from the #GstRegistry), you * can add any object that subclasses #GstPluginFeature. * * Usually plugins are always automaticlly loaded so you don't need to call * gst_plugin_load() explicitly to bring it into memory. There are options to * statically link plugins to an app or even use GStreamer without a plugin * repository in which case gst_plugin_load() can be needed to bring the plugin * into memory. */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include #ifdef HAVE_DIRENT_H #include #endif #ifdef HAVE_UNISTD_H #include #endif #include #include #include "gst_private.h" #include "glib-compat-private.h" #include #define GST_CAT_DEFAULT GST_CAT_PLUGIN_LOADING static guint _num_static_plugins; /* 0 */ static GstPluginDesc *_static_plugins; /* NULL */ static gboolean _gst_plugin_inited; /* static variables for segfault handling of plugin loading */ static char *_gst_plugin_fault_handler_filename = NULL; /* list of valid licenses. * One of these must be specified or the plugin won't be loaded * Contact gstreamer-devel@lists.sourceforge.net if your license should be * added. * * GPL: http://www.gnu.org/copyleft/gpl.html * LGPL: http://www.gnu.org/copyleft/lesser.html * QPL: http://www.trolltech.com/licenses/qpl.html * MPL: http://www.opensource.org/licenses/mozilla1.1.php * MIT/X11: http://www.opensource.org/licenses/mit-license.php * 3-clause BSD: http://www.opensource.org/licenses/bsd-license.php */ static const gchar *valid_licenses[] = { "LGPL", /* GNU Lesser General Public License */ "GPL", /* GNU General Public License */ "QPL", /* Trolltech Qt Public License */ "GPL/QPL", /* Combi-license of GPL + QPL */ "MPL", /* MPL 1.1 license */ "BSD", /* 3-clause BSD license */ "MIT/X11", /* MIT/X11 license */ "Proprietary", /* Proprietary license */ GST_LICENSE_UNKNOWN, /* some other license */ NULL }; static GstPlugin *gst_plugin_register_func (GstPlugin * plugin, const GstPluginDesc * desc, gpointer user_data); static void gst_plugin_desc_copy (GstPluginDesc * dest, const GstPluginDesc * src); static void gst_plugin_desc_free (GstPluginDesc * desc); static void gst_plugin_ext_dep_free (GstPluginDep * dep); G_DEFINE_TYPE (GstPlugin, gst_plugin, GST_TYPE_OBJECT); static void gst_plugin_init (GstPlugin * plugin) { plugin->priv = G_TYPE_INSTANCE_GET_PRIVATE (plugin, GST_TYPE_PLUGIN, GstPluginPrivate); } static void gst_plugin_finalize (GObject * object) { GstPlugin *plugin = GST_PLUGIN_CAST (object); GstRegistry *registry = gst_registry_get_default (); GList *g; GST_DEBUG ("finalizing plugin %p", plugin); for (g = registry->plugins; g; g = g->next) { if (g->data == (gpointer) plugin) { g_warning ("removing plugin that is still in registry"); } } g_free (plugin->filename); g_free (plugin->basename); gst_plugin_desc_free (&plugin->desc); g_list_foreach (plugin->priv->deps, (GFunc) gst_plugin_ext_dep_free, NULL); g_list_free (plugin->priv->deps); plugin->priv->deps = NULL; if (plugin->priv->cache_data) { gst_structure_free (plugin->priv->cache_data); } G_OBJECT_CLASS (gst_plugin_parent_class)->finalize (object); } static void gst_plugin_class_init (GstPluginClass * klass) { G_OBJECT_CLASS (klass)->finalize = GST_DEBUG_FUNCPTR (gst_plugin_finalize); g_type_class_add_private (klass, sizeof (GstPluginPrivate)); } GQuark gst_plugin_error_quark (void) { static GQuark quark = 0; if (!quark) quark = g_quark_from_static_string ("gst_plugin_error"); return quark; } #ifndef GST_REMOVE_DEPRECATED /* this function can be called in the GCC constructor extension, before * the _gst_plugin_initialize() was called. In that case, we store the * plugin description in a list to initialize it when we open the main * module later on. * When the main module is known, we can register the plugin right away. */ void _gst_plugin_register_static (GstPluginDesc * desc) { g_return_if_fail (desc != NULL); if (!_gst_plugin_inited) { /* We can't use any GLib functions here, since g_thread_init hasn't been * called yet, and we can't call it here either, or programs that don't * guard their g_thread_init calls in main() will just abort */ ++_num_static_plugins; _static_plugins = realloc (_static_plugins, _num_static_plugins * sizeof (GstPluginDesc)); /* assume strings in the GstPluginDesc are static const or live forever */ _static_plugins[_num_static_plugins - 1] = *desc; } else { gst_plugin_register_static (desc->major_version, desc->minor_version, desc->name, desc->description, desc->plugin_init, desc->version, desc->license, desc->source, desc->package, desc->origin); } } #endif /** * gst_plugin_register_static: * @major_version: the major version number of the GStreamer core that the * plugin was compiled for, you can just use GST_VERSION_MAJOR here * @minor_version: the minor version number of the GStreamer core that the * plugin was compiled for, you can just use GST_VERSION_MINOR here * @name: a unique name of the plugin (ideally prefixed with an application- or * library-specific namespace prefix in order to avoid name conflicts in * case a similar plugin with the same name ever gets added to GStreamer) * @description: description of the plugin * @init_func: pointer to the init function of this plugin. * @version: version string of the plugin * @license: effective license of plugin. Must be one of the approved licenses * (see #GstPluginDesc above) or the plugin will not be registered. * @source: source module plugin belongs to * @package: shipped package plugin belongs to * @origin: URL to provider of plugin * * Registers a static plugin, ie. a plugin which is private to an application * or library and contained within the application or library (as opposed to * being shipped as a separate module file). * * You must make sure that GStreamer has been initialised (with gst_init() or * via gst_init_get_option_group()) before calling this function. * * Returns: TRUE if the plugin was registered correctly, otherwise FALSE. * * Since: 0.10.16 */ gboolean gst_plugin_register_static (gint major_version, gint minor_version, const gchar * name, gchar * description, GstPluginInitFunc init_func, const gchar * version, const gchar * license, const gchar * source, const gchar * package, const gchar * origin) { GstPluginDesc desc = { major_version, minor_version, name, description, init_func, version, license, source, package, origin, }; GstPlugin *plugin; gboolean res = FALSE; g_return_val_if_fail (name != NULL, FALSE); g_return_val_if_fail (description != NULL, FALSE); g_return_val_if_fail (init_func != NULL, FALSE); g_return_val_if_fail (version != NULL, FALSE); g_return_val_if_fail (license != NULL, FALSE); g_return_val_if_fail (source != NULL, FALSE); g_return_val_if_fail (package != NULL, FALSE); g_return_val_if_fail (origin != NULL, FALSE); /* make sure gst_init() has been called */ g_return_val_if_fail (_gst_plugin_inited != FALSE, FALSE); GST_LOG ("attempting to load static plugin \"%s\" now...", name); plugin = g_object_new (GST_TYPE_PLUGIN, NULL); if (gst_plugin_register_func (plugin, &desc, NULL) != NULL) { GST_INFO ("registered static plugin \"%s\"", name); res = gst_default_registry_add_plugin (plugin); GST_INFO ("added static plugin \"%s\", result: %d", name, res); } return res; } /** * gst_plugin_register_static_full: * @major_version: the major version number of the GStreamer core that the * plugin was compiled for, you can just use GST_VERSION_MAJOR here * @minor_version: the minor version number of the GStreamer core that the * plugin was compiled for, you can just use GST_VERSION_MINOR here * @name: a unique name of the plugin (ideally prefixed with an application- or * library-specific namespace prefix in order to avoid name conflicts in * case a similar plugin with the same name ever gets added to GStreamer) * @description: description of the plugin * @init_full_func: pointer to the init function with user data of this plugin. * @version: version string of the plugin * @license: effective license of plugin. Must be one of the approved licenses * (see #GstPluginDesc above) or the plugin will not be registered. * @source: source module plugin belongs to * @package: shipped package plugin belongs to * @origin: URL to provider of plugin * @user_data: gpointer to user data * * Registers a static plugin, ie. a plugin which is private to an application * or library and contained within the application or library (as opposed to * being shipped as a separate module file) with a #GstPluginInitFullFunc * which allows user data to be passed to the callback function (useful * for bindings). * * You must make sure that GStreamer has been initialised (with gst_init() or * via gst_init_get_option_group()) before calling this function. * * Returns: TRUE if the plugin was registered correctly, otherwise FALSE. * * Since: 0.10.24 * */ gboolean gst_plugin_register_static_full (gint major_version, gint minor_version, const gchar * name, gchar * description, GstPluginInitFullFunc init_full_func, const gchar * version, const gchar * license, const gchar * source, const gchar * package, const gchar * origin, gpointer user_data) { GstPluginDesc desc = { major_version, minor_version, name, description, (GstPluginInitFunc) init_full_func, version, license, source, package, origin, }; GstPlugin *plugin; gboolean res = FALSE; g_return_val_if_fail (name != NULL, FALSE); g_return_val_if_fail (description != NULL, FALSE); g_return_val_if_fail (init_full_func != NULL, FALSE); g_return_val_if_fail (version != NULL, FALSE); g_return_val_if_fail (license != NULL, FALSE); g_return_val_if_fail (source != NULL, FALSE); g_return_val_if_fail (package != NULL, FALSE); g_return_val_if_fail (origin != NULL, FALSE); /* make sure gst_init() has been called */ g_return_val_if_fail (_gst_plugin_inited != FALSE, FALSE); GST_LOG ("attempting to load static plugin \"%s\" now...", name); plugin = g_object_new (GST_TYPE_PLUGIN, NULL); if (gst_plugin_register_func (plugin, &desc, user_data) != NULL) { GST_INFO ("registered static plugin \"%s\"", name); res = gst_default_registry_add_plugin (plugin); GST_INFO ("added static plugin \"%s\", result: %d", name, res); } return res; } void _gst_plugin_initialize (void) { guint i; _gst_plugin_inited = TRUE; /* now register all static plugins */ GST_INFO ("registering %u static plugins", _num_static_plugins); for (i = 0; i < _num_static_plugins; ++i) { gst_plugin_register_static (_static_plugins[i].major_version, _static_plugins[i].minor_version, _static_plugins[i].name, _static_plugins[i].description, _static_plugins[i].plugin_init, _static_plugins[i].version, _static_plugins[i].license, _static_plugins[i].source, _static_plugins[i].package, _static_plugins[i].origin); } if (_static_plugins) { free (_static_plugins); _static_plugins = NULL; _num_static_plugins = 0; } } /* this function could be extended to check if the plugin license matches the * applications license (would require the app to register its license somehow). * We'll wait for someone who's interested in it to code it :) */ static gboolean gst_plugin_check_license (const gchar * license) { const gchar **check_license = valid_licenses; g_assert (check_license); while (*check_license) { if (strcmp (license, *check_license) == 0) return TRUE; check_license++; } return FALSE; } static gboolean gst_plugin_check_version (gint major, gint minor) { /* return NULL if the major and minor version numbers are not compatible */ /* with ours. */ if (major != GST_VERSION_MAJOR || minor != GST_VERSION_MINOR) return FALSE; return TRUE; } static GstPlugin * gst_plugin_register_func (GstPlugin * plugin, const GstPluginDesc * desc, gpointer user_data) { if (!gst_plugin_check_version (desc->major_version, desc->minor_version)) { if (GST_CAT_DEFAULT) GST_WARNING ("plugin \"%s\" has incompatible version, not loading", plugin->filename); return NULL; } if (!desc->license || !desc->description || !desc->source || !desc->package || !desc->origin) { if (GST_CAT_DEFAULT) GST_WARNING ("plugin \"%s\" has incorrect GstPluginDesc, not loading", plugin->filename); return NULL; } if (!gst_plugin_check_license (desc->license)) { if (GST_CAT_DEFAULT) GST_WARNING ("plugin \"%s\" has invalid license \"%s\", not loading", plugin->filename, desc->license); return NULL; } if (GST_CAT_DEFAULT) GST_LOG ("plugin \"%s\" looks good", GST_STR_NULL (plugin->filename)); gst_plugin_desc_copy (&plugin->desc, desc); if (user_data) { if (!(((GstPluginInitFullFunc) (desc->plugin_init)) (plugin, user_data))) { if (GST_CAT_DEFAULT) GST_WARNING ("plugin \"%s\" failed to initialise", plugin->filename); plugin->module = NULL; return NULL; } } else { if (!((desc->plugin_init) (plugin))) { if (GST_CAT_DEFAULT) GST_WARNING ("plugin \"%s\" failed to initialise", plugin->filename); plugin->module = NULL; return NULL; } } if (GST_CAT_DEFAULT) GST_LOG ("plugin \"%s\" initialised", GST_STR_NULL (plugin->filename)); return plugin; } #ifdef HAVE_SIGACTION static struct sigaction oldaction; static gboolean _gst_plugin_fault_handler_is_setup = FALSE; /* * _gst_plugin_fault_handler_restore: * segfault handler restorer */ static void _gst_plugin_fault_handler_restore (void) { if (!_gst_plugin_fault_handler_is_setup) return; _gst_plugin_fault_handler_is_setup = FALSE; sigaction (SIGSEGV, &oldaction, NULL); } /* * _gst_plugin_fault_handler_sighandler: * segfault handler implementation */ static void _gst_plugin_fault_handler_sighandler (int signum) { /* We need to restore the fault handler or we'll keep getting it */ _gst_plugin_fault_handler_restore (); switch (signum) { case SIGSEGV: g_print ("\nERROR: "); g_print ("Caught a segmentation fault while loading plugin file:\n"); g_print ("%s\n\n", _gst_plugin_fault_handler_filename); g_print ("Please either:\n"); g_print ("- remove it and restart.\n"); g_print ("- run with --gst-disable-segtrap and debug.\n"); exit (-1); break; default: g_print ("Caught unhandled signal on plugin loading\n"); break; } } /* * _gst_plugin_fault_handler_setup: * sets up the segfault handler */ static void _gst_plugin_fault_handler_setup (void) { struct sigaction action; /* if asked to leave segfaults alone, just return */ if (!gst_segtrap_is_enabled ()) return; if (_gst_plugin_fault_handler_is_setup) return; _gst_plugin_fault_handler_is_setup = TRUE; memset (&action, 0, sizeof (action)); action.sa_handler = _gst_plugin_fault_handler_sighandler; sigaction (SIGSEGV, &action, &oldaction); } #else /* !HAVE_SIGACTION */ static void _gst_plugin_fault_handler_restore (void) { } static void _gst_plugin_fault_handler_setup (void) { } #endif /* HAVE_SIGACTION */ static void _gst_plugin_fault_handler_setup (); static GStaticMutex gst_plugin_loading_mutex = G_STATIC_MUTEX_INIT; #define CHECK_PLUGIN_DESC_FIELD(desc,field,fn) \ if (G_UNLIKELY ((desc)->field == NULL)) { \ GST_ERROR ("GstPluginDesc for '%s' has no %s", fn, G_STRINGIFY (field)); \ } /** * gst_plugin_load_file: * @filename: the plugin filename to load * @error: pointer to a NULL-valued GError * * Loads the given plugin and refs it. Caller needs to unref after use. * * Returns: a reference to the existing loaded GstPlugin, a reference to the * newly-loaded GstPlugin, or NULL if an error occurred. */ GstPlugin * gst_plugin_load_file (const gchar * filename, GError ** error) { GstPlugin *plugin; GModule *module; gboolean ret; gpointer ptr; struct stat file_status; GstRegistry *registry; gboolean new_plugin = TRUE; g_return_val_if_fail (filename != NULL, NULL); registry = gst_registry_get_default (); g_static_mutex_lock (&gst_plugin_loading_mutex); plugin = gst_registry_lookup (registry, filename); if (plugin) { if (plugin->module) { /* already loaded */ g_static_mutex_unlock (&gst_plugin_loading_mutex); return plugin; } else { /* load plugin and update fields */ new_plugin = FALSE; } } GST_CAT_DEBUG (GST_CAT_PLUGIN_LOADING, "attempt to load plugin \"%s\"", filename); if (g_module_supported () == FALSE) { GST_CAT_DEBUG (GST_CAT_PLUGIN_LOADING, "module loading not supported"); g_set_error (error, GST_PLUGIN_ERROR, GST_PLUGIN_ERROR_MODULE, "Dynamic loading not supported"); goto return_error; } if (g_stat (filename, &file_status)) { GST_CAT_DEBUG (GST_CAT_PLUGIN_LOADING, "problem accessing file"); g_set_error (error, GST_PLUGIN_ERROR, GST_PLUGIN_ERROR_MODULE, "Problem accessing file %s: %s", filename, g_strerror (errno)); goto return_error; } module = g_module_open (filename, G_MODULE_BIND_LOCAL); if (module == NULL) { GST_CAT_WARNING (GST_CAT_PLUGIN_LOADING, "module_open failed: %s", g_module_error ()); g_set_error (error, GST_PLUGIN_ERROR, GST_PLUGIN_ERROR_MODULE, "Opening module failed: %s", g_module_error ()); /* If we failed to open the shared object, then it's probably because a * plugin is linked against the wrong libraries. Print out an easy-to-see * message in this case. */ g_warning ("Failed to load plugin '%s': %s", filename, g_module_error ()); goto return_error; } if (new_plugin) { plugin = g_object_new (GST_TYPE_PLUGIN, NULL); plugin->file_mtime = file_status.st_mtime; plugin->file_size = file_status.st_size; } plugin->module = module; plugin->filename = g_strdup (filename); plugin->basename = g_path_get_basename (filename); ret = g_module_symbol (module, "gst_plugin_desc", &ptr); if (!ret) { GST_DEBUG ("Could not find plugin entry point in \"%s\"", filename); g_set_error (error, GST_PLUGIN_ERROR, GST_PLUGIN_ERROR_MODULE, "File \"%s\" is not a GStreamer plugin", filename); g_module_close (module); goto return_error; } plugin->orig_desc = (GstPluginDesc *) ptr; if (new_plugin) { /* check plugin description: complain about bad values but accept them, to * maintain backwards compatibility (FIXME: 0.11) */ CHECK_PLUGIN_DESC_FIELD (plugin->orig_desc, name, filename); CHECK_PLUGIN_DESC_FIELD (plugin->orig_desc, description, filename); CHECK_PLUGIN_DESC_FIELD (plugin->orig_desc, version, filename); CHECK_PLUGIN_DESC_FIELD (plugin->orig_desc, license, filename); CHECK_PLUGIN_DESC_FIELD (plugin->orig_desc, source, filename); CHECK_PLUGIN_DESC_FIELD (plugin->orig_desc, package, filename); CHECK_PLUGIN_DESC_FIELD (plugin->orig_desc, origin, filename); } GST_LOG ("Plugin %p for file \"%s\" prepared, calling entry function...", plugin, filename); /* this is where we load the actual .so, so let's trap SIGSEGV */ _gst_plugin_fault_handler_setup (); _gst_plugin_fault_handler_filename = plugin->filename; GST_LOG ("Plugin %p for file \"%s\" prepared, registering...", plugin, filename); if (!gst_plugin_register_func (plugin, plugin->orig_desc, NULL)) { /* remove signal handler */ _gst_plugin_fault_handler_restore (); GST_DEBUG ("gst_plugin_register_func failed for plugin \"%s\"", filename); /* plugin == NULL */ g_set_error (error, GST_PLUGIN_ERROR, GST_PLUGIN_ERROR_MODULE, "File \"%s\" appears to be a GStreamer plugin, but it failed to initialize", filename); g_module_close (module); goto return_error; } /* remove signal handler */ _gst_plugin_fault_handler_restore (); _gst_plugin_fault_handler_filename = NULL; GST_INFO ("plugin \"%s\" loaded", plugin->filename); if (new_plugin) { gst_object_ref (plugin); gst_default_registry_add_plugin (plugin); } g_static_mutex_unlock (&gst_plugin_loading_mutex); return plugin; return_error: { if (plugin) gst_object_unref (plugin); g_static_mutex_unlock (&gst_plugin_loading_mutex); return NULL; } } static void gst_plugin_desc_copy (GstPluginDesc * dest, const GstPluginDesc * src) { dest->major_version = src->major_version; dest->minor_version = src->minor_version; dest->name = g_intern_string (src->name); /* maybe intern the description too, just for convenience? */ dest->description = g_strdup (src->description); dest->plugin_init = src->plugin_init; dest->version = g_intern_string (src->version); dest->license = g_intern_string (src->license); dest->source = g_intern_string (src->source); dest->package = g_intern_string (src->package); dest->origin = g_intern_string (src->origin); } /* unused */ static void gst_plugin_desc_free (GstPluginDesc * desc) { g_free (desc->description); memset (desc, 0, sizeof (GstPluginDesc)); } /** * gst_plugin_get_name: * @plugin: plugin to get the name of * * Get the short name of the plugin * * Returns: the name of the plugin */ const gchar * gst_plugin_get_name (GstPlugin * plugin) { g_return_val_if_fail (plugin != NULL, NULL); return plugin->desc.name; } /** * gst_plugin_get_description: * @plugin: plugin to get long name of * * Get the long descriptive name of the plugin * * Returns: the long name of the plugin */ G_CONST_RETURN gchar * gst_plugin_get_description (GstPlugin * plugin) { g_return_val_if_fail (plugin != NULL, NULL); return plugin->desc.description; } /** * gst_plugin_get_filename: * @plugin: plugin to get the filename of * * get the filename of the plugin * * Returns: the filename of the plugin */ G_CONST_RETURN gchar * gst_plugin_get_filename (GstPlugin * plugin) { g_return_val_if_fail (plugin != NULL, NULL); return plugin->filename; } /** * gst_plugin_get_version: * @plugin: plugin to get the version of * * get the version of the plugin * * Returns: the version of the plugin */ G_CONST_RETURN gchar * gst_plugin_get_version (GstPlugin * plugin) { g_return_val_if_fail (plugin != NULL, NULL); return plugin->desc.version; } /** * gst_plugin_get_license: * @plugin: plugin to get the license of * * get the license of the plugin * * Returns: the license of the plugin */ G_CONST_RETURN gchar * gst_plugin_get_license (GstPlugin * plugin) { g_return_val_if_fail (plugin != NULL, NULL); return plugin->desc.license; } /** * gst_plugin_get_source: * @plugin: plugin to get the source of * * get the source module the plugin belongs to. * * Returns: the source of the plugin */ G_CONST_RETURN gchar * gst_plugin_get_source (GstPlugin * plugin) { g_return_val_if_fail (plugin != NULL, NULL); return plugin->desc.source; } /** * gst_plugin_get_package: * @plugin: plugin to get the package of * * get the package the plugin belongs to. * * Returns: the package of the plugin */ G_CONST_RETURN gchar * gst_plugin_get_package (GstPlugin * plugin) { g_return_val_if_fail (plugin != NULL, NULL); return plugin->desc.package; } /** * gst_plugin_get_origin: * @plugin: plugin to get the origin of * * get the URL where the plugin comes from * * Returns: the origin of the plugin */ G_CONST_RETURN gchar * gst_plugin_get_origin (GstPlugin * plugin) { g_return_val_if_fail (plugin != NULL, NULL); return plugin->desc.origin; } /** * gst_plugin_get_module: * @plugin: plugin to query * * Gets the #GModule of the plugin. If the plugin isn't loaded yet, NULL is * returned. * * Returns: module belonging to the plugin or NULL if the plugin isn't * loaded yet. */ GModule * gst_plugin_get_module (GstPlugin * plugin) { g_return_val_if_fail (plugin != NULL, NULL); return plugin->module; } /** * gst_plugin_is_loaded: * @plugin: plugin to query * * queries if the plugin is loaded into memory * * Returns: TRUE is loaded, FALSE otherwise */ gboolean gst_plugin_is_loaded (GstPlugin * plugin) { g_return_val_if_fail (plugin != NULL, FALSE); return (plugin->module != NULL || plugin->filename == NULL); } /** * gst_plugin_get_cache_data: * @plugin: a plugin * * Gets the plugin specific data cache. If it is %NULL there is no cached data * stored. This is the case when the registry is getting rebuild. * * Returns: The cached data as a #GstStructure or %NULL. */ G_CONST_RETURN GstStructure * gst_plugin_get_cache_data (GstPlugin * plugin) { g_return_val_if_fail (GST_IS_PLUGIN (plugin), NULL); return plugin->priv->cache_data; } /** * gst_plugin_set_cache_data: * @plugin: a plugin * @cache_data: a structure containing the data to cache * * Adds plugin specific data to cache. Passes the ownership of the structure to * the @plugin. * * The cache is flushed every time the registry is rebuild. */ void gst_plugin_set_cache_data (GstPlugin * plugin, GstStructure * cache_data) { g_return_if_fail (GST_IS_PLUGIN (plugin)); g_return_if_fail (GST_IS_STRUCTURE (cache_data)); if (plugin->priv->cache_data) { gst_structure_free (plugin->priv->cache_data); } plugin->priv->cache_data = cache_data; } #if 0 /** * gst_plugin_feature_list: * @plugin: plugin to query * @filter: the filter to use * @first: only return first match * @user_data: user data passed to the filter function * * Runs a filter against all plugin features and returns a GList with * the results. If the first flag is set, only the first match is * returned (as a list with a single object). * * Returns: a GList of features, g_list_free after use. */ GList * gst_plugin_feature_filter (GstPlugin * plugin, GstPluginFeatureFilter filter, gboolean first, gpointer user_data) { GList *list; GList *g; list = gst_filter_run (plugin->features, (GstFilterFunc) filter, first, user_data); for (g = list; g; g = g->next) { gst_object_ref (plugin); } return list; } typedef struct { GstPluginFeatureFilter filter; gboolean first; gpointer user_data; GList *result; } FeatureFilterData; static gboolean _feature_filter (GstPlugin * plugin, gpointer user_data) { GList *result; FeatureFilterData *data = (FeatureFilterData *) user_data; result = gst_plugin_feature_filter (plugin, data->filter, data->first, data->user_data); if (result) { data->result = g_list_concat (data->result, result); return TRUE; } return FALSE; } /** * gst_plugin_list_feature_filter: * @list: a #GList of plugins to query * @filter: the filter function to use * @first: only return first match * @user_data: user data passed to the filter function * * Runs a filter against all plugin features of the plugins in the given * list and returns a GList with the results. * If the first flag is set, only the first match is * returned (as a list with a single object). * * Returns: a GList of features, g_list_free after use. */ GList * gst_plugin_list_feature_filter (GList * list, GstPluginFeatureFilter filter, gboolean first, gpointer user_data) { FeatureFilterData data; GList *result; data.filter = filter; data.first = first; data.user_data = user_data; data.result = NULL; result = gst_filter_run (list, (GstFilterFunc) _feature_filter, first, &data); g_list_free (result); return data.result; } #endif /** * gst_plugin_name_filter: * @plugin: the plugin to check * @name: the name of the plugin * * A standard filter that returns TRUE when the plugin is of the * given name. * * Returns: TRUE if the plugin is of the given name. */ gboolean gst_plugin_name_filter (GstPlugin * plugin, const gchar * name) { return (plugin->desc.name && !strcmp (plugin->desc.name, name)); } #if 0 /** * gst_plugin_find_feature: * @plugin: plugin to get the feature from * @name: The name of the feature to find * @type: The type of the feature to find * * Find a feature of the given name and type in the given plugin. * * Returns: a GstPluginFeature or NULL if the feature was not found. */ GstPluginFeature * gst_plugin_find_feature (GstPlugin * plugin, const gchar * name, GType type) { GList *walk; GstPluginFeature *result = NULL; GstTypeNameData data; g_return_val_if_fail (name != NULL, NULL); data.type = type; data.name = name; walk = gst_filter_run (plugin->features, (GstFilterFunc) gst_plugin_feature_type_name_filter, TRUE, &data); if (walk) { result = GST_PLUGIN_FEATURE (walk->data); gst_object_ref (result); gst_plugin_feature_list_free (walk); } return result; } #endif #if 0 static gboolean gst_plugin_feature_name_filter (GstPluginFeature * feature, const gchar * name) { return !strcmp (name, GST_PLUGIN_FEATURE_NAME (feature)); } #endif #if 0 /** * gst_plugin_find_feature_by_name: * @plugin: plugin to get the feature from * @name: The name of the feature to find * * Find a feature of the given name in the given plugin. * * Returns: a GstPluginFeature or NULL if the feature was not found. */ GstPluginFeature * gst_plugin_find_feature_by_name (GstPlugin * plugin, const gchar * name) { GList *walk; GstPluginFeature *result = NULL; g_return_val_if_fail (name != NULL, NULL); walk = gst_filter_run (plugin->features, (GstFilterFunc) gst_plugin_feature_name_filter, TRUE, (void *) name); if (walk) { result = GST_PLUGIN_FEATURE (walk->data); gst_object_ref (result); gst_plugin_feature_list_free (walk); } return result; } #endif /** * gst_plugin_load_by_name: * @name: name of plugin to load * * Load the named plugin. Refs the plugin. * * Returns: A reference to a loaded plugin, or NULL on error. */ GstPlugin * gst_plugin_load_by_name (const gchar * name) { GstPlugin *plugin, *newplugin; GError *error = NULL; GST_DEBUG ("looking up plugin %s in default registry", name); plugin = gst_registry_find_plugin (gst_registry_get_default (), name); if (plugin) { GST_DEBUG ("loading plugin %s from file %s", name, plugin->filename); newplugin = gst_plugin_load_file (plugin->filename, &error); gst_object_unref (plugin); if (!newplugin) { GST_WARNING ("load_plugin error: %s", error->message); g_error_free (error); return NULL; } /* newplugin was reffed by load_file */ return newplugin; } GST_DEBUG ("Could not find plugin %s in registry", name); return NULL; } /** * gst_plugin_load: * @plugin: plugin to load * * Loads @plugin. Note that the *return value* is the loaded plugin; @plugin is * untouched. The normal use pattern of this function goes like this: * * * GstPlugin *loaded_plugin; * loaded_plugin = gst_plugin_load (plugin); * // presumably, we're no longer interested in the potentially-unloaded plugin * gst_object_unref (plugin); * plugin = loaded_plugin; * * * Returns: A reference to a loaded plugin, or NULL on error. */ GstPlugin * gst_plugin_load (GstPlugin * plugin) { GError *error = NULL; GstPlugin *newplugin; if (gst_plugin_is_loaded (plugin)) { return plugin; } if (!(newplugin = gst_plugin_load_file (plugin->filename, &error))) goto load_error; return newplugin; load_error: { GST_WARNING ("load_plugin error: %s", error->message); g_error_free (error); return NULL; } } /** * gst_plugin_list_free: * @list: list of #GstPlugin * * Unrefs each member of @list, then frees the list. */ void gst_plugin_list_free (GList * list) { GList *g; for (g = list; g; g = g->next) { gst_object_unref (GST_PLUGIN_CAST (g->data)); } g_list_free (list); } /* ===== plugin dependencies ===== */ /* Scenarios: * ENV + xyz where ENV can contain multiple values separated by SEPARATOR * xyz may be "" (if ENV contains path to file rather than dir) * ENV + *xyz same as above, but xyz acts as suffix filter * ENV + xyz* same as above, but xyz acts as prefix filter (is this needed?) * ENV + *xyz* same as above, but xyz acts as strstr filter (is this needed?) * * same as above, with additional paths hard-coded at compile-time: * - only check paths + ... if ENV is not set or yields not paths * - always check paths + ... in addition to ENV * * When user specifies set of environment variables, he/she may also use e.g. * "HOME/.mystuff/plugins", and we'll expand the content of $HOME with the * remainder */ /* we store in registry: * sets of: * { * - environment variables (array of strings) * - last hash of env variable contents (uint) (so we can avoid doing stats * if one of the env vars has changed; premature optimisation galore) * - hard-coded paths (array of strings) * - xyz filename/suffix/prefix strings (array of strings) * - flags (int) * - last hash of file/dir stats (int) * } * (= struct GstPluginDep) */ static guint gst_plugin_ext_dep_get_env_vars_hash (GstPlugin * plugin, GstPluginDep * dep) { gchar **e; guint hash; /* there's no deeper logic to what we do here; all we want to know (when * checking if the plugin needs to be rescanned) is whether the content of * one of the environment variables in the list is different from when it * was last scanned */ hash = 0; for (e = dep->env_vars; e != NULL && *e != NULL; ++e) { const gchar *val; gchar env_var[256]; /* order matters: "val",NULL needs to yield a different hash than * NULL,"val", so do a shift here whether the var is set or not */ hash = hash << 5; /* want environment variable at beginning of string */ if (!g_ascii_isalnum (**e)) { GST_WARNING_OBJECT (plugin, "string prefix is not a valid environment " "variable string: %s", *e); continue; } /* user is allowed to specify e.g. "HOME/.pitivi/plugins" */ g_strlcpy (env_var, *e, sizeof (env_var)); g_strdelimit (env_var, "/\\", '\0'); if ((val = g_getenv (env_var))) hash += g_str_hash (val); } return hash; } gboolean _priv_plugin_deps_env_vars_changed (GstPlugin * plugin) { GList *l; for (l = plugin->priv->deps; l != NULL; l = l->next) { GstPluginDep *dep = l->data; if (dep->env_hash != gst_plugin_ext_dep_get_env_vars_hash (plugin, dep)) return TRUE; } return FALSE; } static GList * gst_plugin_ext_dep_extract_env_vars_paths (GstPlugin * plugin, GstPluginDep * dep) { gchar **evars; GList *paths = NULL; for (evars = dep->env_vars; evars != NULL && *evars != NULL; ++evars) { const gchar *e; gchar **components; /* want environment variable at beginning of string */ if (!g_ascii_isalnum (**evars)) { GST_WARNING_OBJECT (plugin, "string prefix is not a valid environment " "variable string: %s", *evars); continue; } /* user is allowed to specify e.g. "HOME/.pitivi/plugins", which we want to * split into the env_var name component and the path component */ components = g_strsplit_set (*evars, "/\\", 2); g_assert (components != NULL); e = g_getenv (components[0]); GST_LOG_OBJECT (plugin, "expanding %s = '%s' (path suffix: %s)", components[0], GST_STR_NULL (e), GST_STR_NULL (components[1])); if (components[1] != NULL) { g_strdelimit (components[1], "/\\", G_DIR_SEPARATOR); } if (e != NULL && *e != '\0') { gchar **arr; guint i; arr = g_strsplit (e, G_SEARCHPATH_SEPARATOR_S, -1); for (i = 0; arr != NULL && arr[i] != NULL; ++i) { gchar *full_path; if (!g_path_is_absolute (arr[i])) { GST_INFO_OBJECT (plugin, "ignoring environment variable content '%s'" ": either not an absolute path or not a path at all", arr[i]); continue; } if (components[1] != NULL) { full_path = g_build_filename (arr[i], components[1], NULL); } else { full_path = g_strdup (arr[i]); } if (!g_list_find_custom (paths, full_path, (GCompareFunc) strcmp)) { GST_LOG_OBJECT (plugin, "path: '%s'", full_path); paths = g_list_prepend (paths, full_path); full_path = NULL; } else { GST_LOG_OBJECT (plugin, "path: '%s' (duplicate,ignoring)", full_path); g_free (full_path); } } g_strfreev (arr); } g_strfreev (components); } GST_LOG_OBJECT (plugin, "Extracted %d paths from environment", g_list_length (paths)); return paths; } static guint gst_plugin_ext_dep_get_hash_from_stat_entry (struct stat *s) { if (!(s->st_mode & (S_IFDIR | S_IFREG))) return (guint) - 1; /* completely random formula */ return ((s->st_size << 3) + (s->st_mtime << 5)) ^ s->st_ctime; } static gboolean gst_plugin_ext_dep_direntry_matches (GstPlugin * plugin, const gchar * entry, const gchar ** filenames, GstPluginDependencyFlags flags) { /* no filenames specified, match all entries for now (could probably * optimise by just taking the dir stat hash or so) */ if (filenames == NULL || *filenames == NULL || **filenames == '\0') return TRUE; while (*filenames != NULL) { /* suffix match? */ if (((flags & GST_PLUGIN_DEPENDENCY_FLAG_FILE_NAME_IS_SUFFIX)) && g_str_has_suffix (entry, *filenames)) { return TRUE; /* else it's an exact match that's needed */ } else if (strcmp (entry, *filenames) == 0) { return TRUE; } GST_LOG ("%s does not match %s, flags=0x%04x", entry, *filenames, flags); ++filenames; } return FALSE; } static guint gst_plugin_ext_dep_scan_dir_and_match_names (GstPlugin * plugin, const gchar * path, const gchar ** filenames, GstPluginDependencyFlags flags, int depth) { const gchar *entry; gboolean recurse_dirs; GError *err = NULL; GDir *dir; guint hash = 0; recurse_dirs = !!(flags & GST_PLUGIN_DEPENDENCY_FLAG_RECURSE); dir = g_dir_open (path, 0, &err); if (dir == NULL) { GST_DEBUG_OBJECT (plugin, "g_dir_open(%s) failed: %s", path, err->message); g_error_free (err); return (guint) - 1; } /* FIXME: we're assuming here that we always get the directory entries in * the same order, and not in a random order */ while ((entry = g_dir_read_name (dir))) { gboolean have_match; struct stat s; gchar *full_path; guint fhash; have_match = gst_plugin_ext_dep_direntry_matches (plugin, entry, filenames, flags); /* avoid the stat if possible */ if (!have_match && !recurse_dirs) continue; full_path = g_build_filename (path, entry, NULL); if (g_stat (full_path, &s) < 0) { fhash = (guint) - 1; GST_LOG_OBJECT (plugin, "stat: %s (error: %s)", full_path, g_strerror (errno)); } else if (have_match) { fhash = gst_plugin_ext_dep_get_hash_from_stat_entry (&s); GST_LOG_OBJECT (plugin, "stat: %s (result: %u)", full_path, fhash); } else if ((s.st_mode & (S_IFDIR))) { fhash = gst_plugin_ext_dep_scan_dir_and_match_names (plugin, full_path, filenames, flags, depth + 1); } else { /* it's not a name match, we want to recurse, but it's not a directory */ g_free (full_path); continue; } hash = (hash + fhash) << 1; g_free (full_path); } g_dir_close (dir); return hash; } static guint gst_plugin_ext_dep_scan_path_with_filenames (GstPlugin * plugin, const gchar * path, const gchar ** filenames, GstPluginDependencyFlags flags) { const gchar *empty_filenames[] = { "", NULL }; gboolean recurse_into_dirs, partial_names; guint i, hash = 0; /* to avoid special-casing below (FIXME?) */ if (filenames == NULL || *filenames == NULL) filenames = empty_filenames; recurse_into_dirs = !!(flags & GST_PLUGIN_DEPENDENCY_FLAG_RECURSE); partial_names = !!(flags & GST_PLUGIN_DEPENDENCY_FLAG_FILE_NAME_IS_SUFFIX); /* if we can construct the exact paths to check with the data we have, just * stat them one by one; this is more efficient than opening the directory * and going through each entry to see if it matches one of our filenames. */ if (!recurse_into_dirs && !partial_names) { for (i = 0; filenames[i] != NULL; ++i) { struct stat s; gchar *full_path; guint fhash; full_path = g_build_filename (path, filenames[i], NULL); if (g_stat (full_path, &s) < 0) { fhash = (guint) - 1; GST_LOG_OBJECT (plugin, "stat: %s (error: %s)", full_path, g_strerror (errno)); } else { fhash = gst_plugin_ext_dep_get_hash_from_stat_entry (&s); GST_LOG_OBJECT (plugin, "stat: %s (result: %08x)", full_path, fhash); } hash = (hash + fhash) << 1; g_free (full_path); } } else { hash = gst_plugin_ext_dep_scan_dir_and_match_names (plugin, path, filenames, flags, 0); } return hash; } static guint gst_plugin_ext_dep_get_stat_hash (GstPlugin * plugin, GstPluginDep * dep) { gboolean paths_are_default_only; GList *scan_paths; guint scan_hash = 0; GST_LOG_OBJECT (plugin, "start"); paths_are_default_only = dep->flags & GST_PLUGIN_DEPENDENCY_FLAG_PATHS_ARE_DEFAULT_ONLY; scan_paths = gst_plugin_ext_dep_extract_env_vars_paths (plugin, dep); if (scan_paths == NULL || !paths_are_default_only) { gchar **paths; for (paths = dep->paths; paths != NULL && *paths != NULL; ++paths) { const gchar *path = *paths; if (!g_list_find_custom (scan_paths, path, (GCompareFunc) strcmp)) { GST_LOG_OBJECT (plugin, "path: '%s'", path); scan_paths = g_list_prepend (scan_paths, g_strdup (path)); } else { GST_LOG_OBJECT (plugin, "path: '%s' (duplicate, ignoring)", path); } } } /* not that the order really matters, but it makes debugging easier */ scan_paths = g_list_reverse (scan_paths); while (scan_paths != NULL) { const gchar *path = scan_paths->data; scan_hash += gst_plugin_ext_dep_scan_path_with_filenames (plugin, path, (const gchar **) dep->names, dep->flags); scan_hash = scan_hash << 1; g_free (scan_paths->data); scan_paths = g_list_delete_link (scan_paths, scan_paths); } GST_LOG_OBJECT (plugin, "done, scan_hash: %08x", scan_hash); return scan_hash; } gboolean _priv_plugin_deps_files_changed (GstPlugin * plugin) { GList *l; for (l = plugin->priv->deps; l != NULL; l = l->next) { GstPluginDep *dep = l->data; if (dep->stat_hash != gst_plugin_ext_dep_get_stat_hash (plugin, dep)) return TRUE; } return FALSE; } static void gst_plugin_ext_dep_free (GstPluginDep * dep) { g_strfreev (dep->env_vars); g_strfreev (dep->paths); g_strfreev (dep->names); g_free (dep); } static gboolean gst_plugin_ext_dep_strv_equal (gchar ** arr1, gchar ** arr2) { if (arr1 == arr2) return TRUE; if (arr1 == NULL || arr2 == NULL) return FALSE; for (; *arr1 != NULL && *arr2 != NULL; ++arr1, ++arr2) { if (strcmp (*arr1, *arr2) != 0) return FALSE; } return (*arr1 == *arr2); } static gboolean gst_plugin_ext_dep_equals (GstPluginDep * dep, const gchar ** env_vars, const gchar ** paths, const gchar ** names, GstPluginDependencyFlags flags) { if (dep->flags != flags) return FALSE; return gst_plugin_ext_dep_strv_equal (dep->env_vars, (gchar **) env_vars) && gst_plugin_ext_dep_strv_equal (dep->paths, (gchar **) paths) && gst_plugin_ext_dep_strv_equal (dep->names, (gchar **) names); } /** * gst_plugin_add_dependency: * @plugin: a #GstPlugin * @env_vars: NULL-terminated array of environent variables affecting the * feature set of the plugin (e.g. an environment variable containing * paths where to look for additional modules/plugins of a library), * or NULL. Environment variable names may be followed by a path component * which will be added to the content of the environment variable, e.g. * "HOME/.mystuff/plugins". * @paths: NULL-terminated array of directories/paths where dependent files * may be. * @names: NULL-terminated array of file names (or file name suffixes, * depending on @flags) to be used in combination with the paths from * @paths and/or the paths extracted from the environment variables in * @env_vars, or NULL. * @flags: optional flags, or #GST_PLUGIN_DEPENDENCY_FLAG_NONE * * Make GStreamer aware of external dependencies which affect the feature * set of this plugin (ie. the elements or typefinders associated with it). * * GStreamer will re-inspect plugins with external dependencies whenever any * of the external dependencies change. This is useful for plugins which wrap * other plugin systems, e.g. a plugin which wraps a plugin-based visualisation * library and makes visualisations available as GStreamer elements, or a * codec loader which exposes elements and/or caps dependent on what external * codec libraries are currently installed. * * Since: 0.10.22 */ void gst_plugin_add_dependency (GstPlugin * plugin, const gchar ** env_vars, const gchar ** paths, const gchar ** names, GstPluginDependencyFlags flags) { GstPluginDep *dep; GList *l; g_return_if_fail (GST_IS_PLUGIN (plugin)); g_return_if_fail (env_vars != NULL || paths != NULL); for (l = plugin->priv->deps; l != NULL; l = l->next) { if (gst_plugin_ext_dep_equals (l->data, env_vars, paths, names, flags)) { GST_LOG_OBJECT (plugin, "dependency already registered"); return; } } dep = g_new0 (GstPluginDep, 1); dep->env_vars = g_strdupv ((gchar **) env_vars); dep->paths = g_strdupv ((gchar **) paths); dep->names = g_strdupv ((gchar **) names); dep->flags = flags; dep->env_hash = gst_plugin_ext_dep_get_env_vars_hash (plugin, dep); dep->stat_hash = gst_plugin_ext_dep_get_stat_hash (plugin, dep); plugin->priv->deps = g_list_append (plugin->priv->deps, dep); GST_DEBUG_OBJECT (plugin, "added dependency:"); for (; env_vars != NULL && *env_vars != NULL; ++env_vars) GST_DEBUG_OBJECT (plugin, " evar: %s", *env_vars); for (; paths != NULL && *paths != NULL; ++paths) GST_DEBUG_OBJECT (plugin, " path: %s", *paths); for (; names != NULL && *names != NULL; ++names) GST_DEBUG_OBJECT (plugin, " name: %s", *names); } /** * gst_plugin_add_dependency_simple: * @plugin: the #GstPlugin * @env_vars: one or more environent variables (separated by ':', ';' or ','), * or NULL. Environment variable names may be followed by a path component * which will be added to the content of the environment variable, e.g. * "HOME/.mystuff/plugins:MYSTUFF_PLUGINS_PATH" * @paths: one ore more directory paths (separated by ':' or ';' or ','), * or NULL. Example: "/usr/lib/mystuff/plugins" * @names: one or more file names or file name suffixes (separated by commas), * or NULL * @flags: optional flags, or #GST_PLUGIN_DEPENDENCY_FLAG_NONE * * Make GStreamer aware of external dependencies which affect the feature * set of this plugin (ie. the elements or typefinders associated with it). * * GStreamer will re-inspect plugins with external dependencies whenever any * of the external dependencies change. This is useful for plugins which wrap * other plugin systems, e.g. a plugin which wraps a plugin-based visualisation * library and makes visualisations available as GStreamer elements, or a * codec loader which exposes elements and/or caps dependent on what external * codec libraries are currently installed. * * Convenience wrapper function for gst_plugin_add_dependency() which * takes simple strings as arguments instead of string arrays, with multiple * arguments separated by predefined delimiters (see above). * * Since: 0.10.22 */ void gst_plugin_add_dependency_simple (GstPlugin * plugin, const gchar * env_vars, const gchar * paths, const gchar * names, GstPluginDependencyFlags flags) { gchar **a_evars = NULL; gchar **a_paths = NULL; gchar **a_names = NULL; if (env_vars) a_evars = g_strsplit_set (env_vars, ":;,", -1); if (paths) a_paths = g_strsplit_set (paths, ":;,", -1); if (names) a_names = g_strsplit_set (names, ",", -1); gst_plugin_add_dependency (plugin, (const gchar **) a_evars, (const gchar **) a_paths, (const gchar **) a_names, flags); if (a_evars) g_strfreev (a_evars); if (a_paths) g_strfreev (a_paths); if (a_names) g_strfreev (a_names); }