network-manager-wireguard/shared/nm-utils/nm-vpn-plugin-utils.c

131 lines
4.6 KiB
C

/* -*- Mode: C; tab-width: 4; indent-tabs-mode: t; c-basic-offset: 4 -*- */
/*
* 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, write to the
* Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301 USA.
*
* Copyright 2016 Red Hat, Inc.
*/
#include "nm-default.h"
#include "nm-vpn-plugin-utils.h"
#include <dlfcn.h>
/*****************************************************************************/
NMVpnEditor *
nm_vpn_plugin_utils_load_editor (const char *module_name,
const char *factory_name,
NMVpnPluginUtilsEditorFactory editor_factory,
NMVpnEditorPlugin *editor_plugin,
NMConnection *connection,
gpointer user_data,
GError **error)
{
static struct {
gpointer factory;
void *dl_module;
char *module_name;
char *factory_name;
} cached = { 0 };
NMVpnEditor *editor;
g_return_val_if_fail (module_name && g_path_is_absolute (module_name), NULL);
g_return_val_if_fail (factory_name && factory_name[0], NULL);
g_return_val_if_fail (editor_factory, NULL);
g_return_val_if_fail (NM_IS_VPN_EDITOR_PLUGIN (editor_plugin), NULL);
g_return_val_if_fail (NM_IS_CONNECTION (connection), NULL);
g_return_val_if_fail (!error || !*error, NULL);
/* we really expect this function to be called with unchanging @module_name
* and @factory_name. And we only want to load the module once, hence it would
* be more complicated to accept changing @module_name/@factory_name arguments.
*
* The reason for only loading once is that due to glib types, we cannot create a
* certain type-name more then once, so loading the same module or another version
* of the same module will fail horribly as both try to create a GType with the same
* name.
*
* Only support loading once, any future calls will reuse the handle. To simplify
* that, we enforce that the @factory_name and @module_name is the same. */
if (cached.factory) {
g_return_val_if_fail (cached.dl_module, NULL);
g_return_val_if_fail (cached.factory_name && nm_streq0 (cached.factory_name, factory_name), NULL);
g_return_val_if_fail (cached.module_name && nm_streq0 (cached.module_name, module_name), NULL);
} else {
gpointer factory;
void *dl_module;
dl_module = dlopen (module_name, RTLD_LAZY | RTLD_LOCAL);
if (!dl_module) {
if (!g_file_test (module_name, G_FILE_TEST_EXISTS)) {
g_set_error (error,
G_FILE_ERROR,
G_FILE_ERROR_NOENT,
_("missing plugin file \"%s\""), module_name);
return NULL;
}
g_set_error (error,
NM_CONNECTION_ERROR,
NM_CONNECTION_ERROR_FAILED,
_("cannot load editor plugin: %s"), dlerror ());
return NULL;
}
factory = dlsym (dl_module, factory_name);
if (!factory) {
g_set_error (error,
NM_CONNECTION_ERROR,
NM_CONNECTION_ERROR_FAILED,
_("cannot load factory %s from plugin: %s"),
factory_name, dlerror ());
dlclose (dl_module);
return NULL;
}
/* we cannot ever unload the module because it creates glib types, which
* cannot be unregistered.
*
* Thus we just leak the dl_module handle indefinitely. */
cached.factory = factory;
cached.dl_module = dl_module;
cached.module_name = g_strdup (module_name);
cached.factory_name = g_strdup (factory_name);
}
editor = editor_factory (cached.factory,
editor_plugin,
connection,
user_data,
error);
if (!editor) {
if (error && !*error ) {
g_set_error_literal (error,
NM_CONNECTION_ERROR,
NM_CONNECTION_ERROR_FAILED,
_("unknown error creating editor instance"));
g_return_val_if_reached (NULL);
}
return NULL;
}
g_return_val_if_fail (NM_IS_VPN_EDITOR (editor), NULL);
return editor;
}