modules: load plugins for choice list on need basis

So far, they were loaded at start-up even if there was no request to
enumerate the choices.

include/vlc_configuration.h

@@ -88,6 +88,7 @@ struct module_config_t
     } list;
     const char **list_text;                /* Friendly names for list values */
     const char *list_cb_name;
+    void *owner;
 };
 
 /*****************************************************************************

src/config/core.c

@@ -355,6 +355,12 @@ ssize_t config_GetIntChoices (vlc_object_t *obj, const char *name,
     size_t count = cfg->list_count;
     if (count == 0)
     {
+        if (module_Map(obj, cfg->owner))
+        {
+            errno = EIO;
+            return -1;
+        }
+
         if (cfg->list.i_cb == NULL)
             return 0;
         return cfg->list.i_cb(obj, name, values, texts);
@@ -465,6 +471,12 @@ ssize_t config_GetPszChoices (vlc_object_t *obj, const char *name,
     size_t count = cfg->list_count;
     if (count == 0)
     {
+        if (module_Map(obj, cfg->owner))
+        {
+            errno = EIO;
+            return -1;
+        }
+
         if (cfg->list.psz_cb == NULL)
             return 0;
         return cfg->list.psz_cb(obj, name, values, texts);

src/modules/bank.c

@@ -201,25 +201,6 @@ static int AllocatePluginFile (module_bank_t *bank, const char *abspath,
     if (plugin == NULL)
         return -1;
 
-    module_t *module = plugin->module;
-    assert(module != NULL);
-
-    /* For now we force loading if the module's config contains callbacks.
-     * Could be optimized by adding an API call.*/
-    for (size_t i = 0; i < plugin->conf.size; i++)
-         if (!atomic_load_explicit(&plugin->loaded, memory_order_relaxed)
-          && plugin->conf.items[i].list_cb_name != NULL)
-         {
-             /* !unloadable not allowed for plugins with callbacks */
-             vlc_plugin_destroy(plugin);
-
-             assert(bank->mode != CACHE_RESET);
-             plugin = module_InitDynamic(bank->obj, abspath, false);
-             if (unlikely(plugin == NULL))
-                 return -1;
-             break;
-         }
-
     module_StoreBank(plugin);
 
     if (bank->mode != CACHE_IGNORE) /* Add entry to bank */

src/modules/cache.c

@@ -280,6 +280,7 @@ static int vlc_cache_load_plugin_config(vlc_plugin_t *plugin, block_t *file)
             if (item->i_type == CONFIG_ITEM_BOOL)
                 plugin->conf.booleans++;
         }
+        item->owner = plugin;
     }
 
     return 0;

src/modules/entry.c

@@ -142,27 +142,30 @@ static module_config_t *vlc_config_create(vlc_plugin_t *plugin, int type)
     }
 
     memset (tab + confsize, 0, sizeof (tab[confsize]));
+    tab += confsize;
+    tab->owner = plugin;
+
     if (IsConfigIntegerType (type))
     {
-        tab[confsize].max.i = INT64_MAX;
-        tab[confsize].min.i = INT64_MIN;
+        tab->max.i = INT64_MAX;
+        tab->min.i = INT64_MIN;
     }
     else if( IsConfigFloatType (type))
     {
-        tab[confsize].max.f = FLT_MAX;
-        tab[confsize].min.f = FLT_MIN;
+        tab->max.f = FLT_MAX;
+        tab->min.f = FLT_MIN;
     }
-    tab[confsize].i_type = type;
+    tab->i_type = type;
 
     if (CONFIG_ITEM(type))
     {
         plugin->conf.count++;
         if (type == CONFIG_ITEM_BOOL)
             plugin->conf.booleans++;
     }
-
     plugin->conf.size++;
-    return tab + confsize;
+
+    return tab;
 }
 
 /**