gplugin/gplugin

Prep for the 0.32.1 release
v0.32.1
2021-07-29, Gary Kramlich
328552e20a3f
Prep for the 0.32.1 release

Testing Done:
compiled

Reviewed at https://reviews.imfreedom.org/r/853/
/*
* Copyright (C) 2011-2020 Gary Kramlich <grim@reaperworld.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <https://www.gnu.org/licenses/>.
*/
#include <gplugin/gplugin-core.h>
#include <gplugin/gplugin-loader.h>
/**
* SECTION:gplugin-loader
* @title: Plugin Loader
* @short_description: Abstract class for loading plugins
*
* GPluginLoader defines the base behavior for loaders of all languages.
*/
/**
* GPLUGIN_TYPE_LOADER:
*
* The standard _get_type macro for #GPluginLoader.
*/
/**
* GPluginLoader:
*
* An abstract class that should not be accessed directly.
*/
/**
* GPluginLoaderClass:
* @supported_extensions: The supported_extensions vfunc returns a #GList of
* file extensions that this loader supports without the
* leading dot. For example: 'so', 'dll', 'py', etc.
* @query: The query vfunc is called when the plugin manager needs to query a
* plugin that has a file extension from @supported_extensions.
* @load: The load vfunc is called when the plugin manager wants to load a
* plugin that was previously queried by this loader.
* @unload: The unload vfunc is called when the plugin manager wants to unload
* a previously loaded plugin from this loader.
*
* #GPluginLoaderClass defines the behavior for loading plugins.
*/
/******************************************************************************
* GObject Implementation
*****************************************************************************/
G_DEFINE_ABSTRACT_TYPE(GPluginLoader, gplugin_loader, G_TYPE_OBJECT);
static void
gplugin_loader_init(G_GNUC_UNUSED GPluginLoader *loader)
{
}
static void
gplugin_loader_class_init(G_GNUC_UNUSED GPluginLoaderClass *klass)
{
}
/******************************************************************************
* API
*****************************************************************************/
/**
* gplugin_loader_query_plugin:
* @loader: The #GPluginLoader instance performing the query.
* @filename: The filename to query.
* @error: (nullable): The return location for a #GError, or %NULL.
*
* This function is called by the plugin manager to ask @loader to query
* @filename and determine if it's a usable plugin.
*
* Return value: (transfer full): A #GPluginPlugin instance or %NULL on
* failure.
*/
GPluginPlugin *
gplugin_loader_query_plugin(
GPluginLoader *loader,
const gchar *filename,
GError **error)
{
GPluginLoaderClass *klass = NULL;
GPluginPlugin *plugin = NULL;
GError *real_error = NULL;
g_return_val_if_fail(loader != NULL, NULL);
g_return_val_if_fail(GPLUGIN_IS_LOADER(loader), NULL);
g_return_val_if_fail(filename, NULL);
g_return_val_if_fail(error != NULL, NULL);
klass = GPLUGIN_LOADER_GET_CLASS(loader);
if(klass != NULL && klass->query != NULL) {
plugin = klass->query(loader, filename, &real_error);
}
if(!GPLUGIN_IS_PLUGIN(plugin)) {
if(real_error == NULL) {
real_error = g_error_new_literal(
GPLUGIN_DOMAIN,
0,
"Failed to query plugin : unknown");
}
g_propagate_error(error, real_error);
} else {
/* If the plugin successfully queried but returned an error, ignore the
* error.
*/
g_clear_error(&real_error);
/* Likewise, make sure the plugin's error is set to NULL. */
g_object_set(G_OBJECT(plugin), "error", NULL, NULL);
gplugin_plugin_set_state(plugin, GPLUGIN_PLUGIN_STATE_QUERIED);
}
return plugin;
}
/**
* gplugin_loader_load_plugin:
* @loader: The #GPluginLoader instance performing the load.
* @plugin: The #GPluginPlugin instance to load.
* @error: (nullable): The return location for a #GError, or %NULL.
*
* This function is called by the plugin manager to ask @loader to load
* @plugin.
*
* Return value: %TRUE if @plugin was loaded successfully, %FALSE otherwise.
*/
gboolean
gplugin_loader_load_plugin(
GPluginLoader *loader,
GPluginPlugin *plugin,
GError **error)
{
GPluginLoaderClass *klass = NULL;
GError *real_error = NULL;
gboolean ret = FALSE;
g_return_val_if_fail(loader != NULL, FALSE);
g_return_val_if_fail(GPLUGIN_IS_LOADER(loader), FALSE);
g_return_val_if_fail(GPLUGIN_IS_PLUGIN(plugin), FALSE);
/* if the plugin is already loaded there's nothing for us to do */
if(gplugin_plugin_get_state(plugin) == GPLUGIN_PLUGIN_STATE_LOADED) {
return TRUE;
}
klass = GPLUGIN_LOADER_GET_CLASS(loader);
if(klass != NULL && klass->load != NULL) {
ret = klass->load(loader, plugin, &real_error);
}
if(!ret) {
if(real_error == NULL) {
real_error = g_error_new_literal(
GPLUGIN_DOMAIN,
0,
"Failed to load plugin : unknown");
}
/* Set the error on the plugin as well. This has to be before we
* propagate the error, because error is invalidate at that point.
*/
g_object_set(plugin, "error", real_error, NULL);
/* Set the state after the error is set, because people might connect
* to the notify signal on the state property.
*/
gplugin_plugin_set_state(plugin, GPLUGIN_PLUGIN_STATE_LOAD_FAILED);
g_propagate_error(error, real_error);
} else {
/* If the plugin successfully loaded but returned an error, ignore the
* error.
*/
g_clear_error(&real_error);
/* Likewise, make sure the plugin's error is set to NULL. */
g_object_set(G_OBJECT(plugin), "error", NULL, NULL);
gplugin_plugin_set_state(plugin, GPLUGIN_PLUGIN_STATE_LOADED);
}
return ret;
}
/**
* gplugin_loader_unload_plugin:
* @loader: The #GPluginLoader instance performing the unload.
* @plugin: The #GPluginPlugin instance to unload.
* @error: (nullable): The return location for a #GError, or %NULL.
*
* This function is called by the plugin manager to ask @loader to unload
* @plugin.
*
* Return value: %TRUE if @plugin was unloaded successfully, %FALSE otherwise.
*/
gboolean
gplugin_loader_unload_plugin(
GPluginLoader *loader,
GPluginPlugin *plugin,
GError **error)
{
GPluginLoaderClass *klass = NULL;
GError *real_error = NULL;
gboolean ret = FALSE;
g_return_val_if_fail(loader != NULL, FALSE);
g_return_val_if_fail(GPLUGIN_IS_LOADER(loader), FALSE);
g_return_val_if_fail(GPLUGIN_IS_PLUGIN(plugin), FALSE);
if(gplugin_plugin_get_state(plugin) != GPLUGIN_PLUGIN_STATE_LOADED) {
return TRUE;
}
klass = GPLUGIN_LOADER_GET_CLASS(loader);
if(klass != NULL && klass->unload != NULL) {
ret = klass->unload(loader, plugin, &real_error);
}
if(!ret) {
if(real_error == NULL) {
real_error = g_error_new_literal(
GPLUGIN_DOMAIN,
0,
"Failed to unload plugin : unknown");
}
g_object_set(G_OBJECT(plugin), "error", real_error, NULL);
/* Set the state after the error is set, because people might connect
* to the notify signal on the state property.
*/
gplugin_plugin_set_state(plugin, GPLUGIN_PLUGIN_STATE_UNLOAD_FAILED);
g_propagate_error(error, real_error);
} else {
/* If the plugin successfully unloaded but returned an error, ignore the
* error.
*/
g_clear_error(error);
gplugin_plugin_set_state(plugin, GPLUGIN_PLUGIN_STATE_QUERIED);
}
return ret;
}
/**
* gplugin_loader_get_supported_extensions:
* @loader: The #GPluginLoader instance.
*
* Returns a #GSList of strings containing the extensions that the loader
* supports. Each extension should not include the dot. For example: so,
* dll, py, etc.
*
* Return value: (element-type utf8) (transfer container): A #GSList of
* extensions that the loader supports.
*/
GSList *
gplugin_loader_get_supported_extensions(GPluginLoader *loader)
{
GPluginLoaderClass *klass = NULL;
g_return_val_if_fail(GPLUGIN_IS_LOADER(loader), NULL);
klass = GPLUGIN_LOADER_GET_CLASS(loader);
if(klass != NULL && klass->supported_extensions) {
return klass->supported_extensions(loader);
}
return NULL;
}