2 * Copyright (C) 2009-2010 Andy Spencer <andy753421@gmail.com>
4 * This program is free software: you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation, either version 3 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program. If not, see <http://www.gnu.org/licenses/>.
19 * SECTION:grits-plugin
20 * @short_description: Plugin support
22 * A plugin in grits is a GObject which implements the GritsPlugin interface.
23 * Additionally, each plugin is compiled to a separate shared object and loaded
24 * conditionally at runtime when the plugin is enabled. Each such shared object
25 * should define a GritsPluginConstructor() function named
26 * grits_plugin_NAME_new which will be called when loading the plugin.
28 * Almost all grits functionality is provided by a set of plugins. Each plugin
29 * can how however much it likes. The interface between plugins and the rest of
30 * grits is intentionally very thin. Since grits is the library, plugins must
31 * manually do everything. For instance, to draw something in the world, the
32 * plugin must add an object to the viewer. Likewise, plugins need to
33 * register callbacks on the viewer in order to receive updates, very little
34 * happens automagically.
36 * That being said, one thing that plugins do do automagically, is provide a
37 * configuration area. Since the plugin doesn't know what application is is
38 * being loaded form, it is better for the application to ask the plugin for
39 * it's confirmation area, not the other way around.
47 #include "grits-plugin.h"
52 static void grits_plugin_base_init(gpointer g_class)
54 static gboolean is_initialized = FALSE;
55 if (!is_initialized) {
56 /* add properties and signals to the interface here */
57 is_initialized = TRUE;
61 GType grits_plugin_get_type()
63 static GType type = 0;
65 static const GTypeInfo info = {
66 sizeof(GritsPluginInterface),
67 grits_plugin_base_init,
70 type = g_type_register_static(G_TYPE_INTERFACE,
71 "GritsPlugin", &info, 0);
77 * grits_plugin_get_name:
80 * Get a short human readable name for a plugin, this is not necessarily the
81 * same as the name of the shared object.
83 * Returns: a short name for the plugin
85 const gchar *grits_plugin_get_name(GritsPlugin *plugin)
87 if (!GRITS_IS_PLUGIN(plugin))
89 return GRITS_PLUGIN_GET_INTERFACE(plugin)->name;
93 * grits_plugin_get_description:
96 * Get a description of a plugin
98 * Returns: a description of the plugin
100 const gchar *grits_plugin_get_description(GritsPlugin *plugin)
102 if (!GRITS_IS_PLUGIN(plugin))
104 return GRITS_PLUGIN_GET_INTERFACE(plugin)->description;
108 * grits_plugin_get_config:
109 * @plugin: the plugin
111 * Each plugin can provide a configuration area. Applications using grits
112 * should display this configuration area to the user so they can modify the
113 * behavior of the plugin.
115 * Returns: a configuration widget for the plugin
117 GtkWidget *grits_plugin_get_config(GritsPlugin *plugin)
119 if (!GRITS_IS_PLUGIN(plugin))
121 GritsPluginInterface *iface = GRITS_PLUGIN_GET_INTERFACE(plugin);
122 return iface->get_config ? iface->get_config(plugin) : NULL;
137 * @dir: the directory to search for plugins in
138 * @prefs: a #GritsPrefs to save the state of plugins, or NULL
140 * Create a new plugin source. If @prefs is not %NULL, the state of the plugins
141 * will be saved when they are either enabled or disabled.
143 * Returns: the new plugin source
145 GritsPlugins *grits_plugins_new(const gchar *dir, GritsPrefs *prefs)
147 g_debug("GritsPlugins: new - dir=%s", dir);
148 GritsPlugins *plugins = g_new0(GritsPlugins, 1);
149 plugins->prefs = prefs;
151 plugins->dir = g_strdup(dir);
155 static void grits_plugins_free_store(GritsPluginStore *store)
157 g_object_unref(store->plugin);
158 /* Flush any possible callbacks before
159 * unloading the plugin code */
160 while (gtk_events_pending())
161 gtk_main_iteration();
162 g_module_close(store->module);
168 * grits_plugins_free:
169 * @plugins: the #GritsPlugins to free
171 * Free data used by a plugin source
173 void grits_plugins_free(GritsPlugins *plugins)
175 g_debug("GritsPlugins: free");
176 for (GList *cur = plugins->plugins; cur; cur = cur->next) {
177 GritsPluginStore *store = cur->data;
178 g_debug("GritsPlugin: freeing %s refs=%d->%d", store->name,
179 G_OBJECT(store->plugin)->ref_count,
180 G_OBJECT(store->plugin)->ref_count-1);
181 grits_plugins_free_store(store);
183 g_list_free(plugins->plugins);
185 g_free(plugins->dir);
190 * grits_plugins_available:
191 * @plugins: the plugin source
193 * Search the plugin directory for shared objects which can be loaded as
196 * Returns: the list of available plugins
198 GList *grits_plugins_available(GritsPlugins *plugins)
200 g_debug("GritsPlugins: available");
202 gchar *dirs[] = {plugins->dir, PLUGINSDIR};
203 g_debug("pluginsdir=%s", PLUGINSDIR);
204 for (int i = 0; i<2; i++) {
207 GDir *dir = g_dir_open(dirs[i], 0, NULL);
210 g_debug(" checking %s", dirs[i]);
212 while ((name = g_dir_read_name(dir))) {
213 if (g_pattern_match_simple("*." G_MODULE_SUFFIX, name)) {
214 gchar **parts = g_strsplit(name, ".", 2);
215 list = g_list_prepend(list, g_strdup(parts[0]));
221 list = g_list_sort(list, (GCompareFunc)strcmp);
222 for (GList *cur = list; cur; cur = cur->next)
223 while (cur->next && g_str_equal(cur->data,cur->next->data)) {
224 GList *tmp = cur->next;
225 list = g_list_remove_link(list, cur);
232 * grits_plugins_load:
233 * @plugins: the plugins source
234 * @name: the name of the plugin to load
235 * @viewer: a #GritsViewer to pass to the plugins constructor
236 * @prefs: a #GritsPrefs to pass to the plugins constructor
238 * @name should be the name of the shared object without the file extension.
239 * This is the same as what is returned by grits_plugins_available().
241 * When loading plugins, the @prefs argument is used, not the #GritsPrefs stored
244 * Returns: the new plugin
246 GritsPlugin *grits_plugins_load(GritsPlugins *plugins, const char *name,
247 GritsViewer *viewer, GritsPrefs *prefs)
249 g_debug("GritsPlugins: load %s", name);
250 gchar *path = g_strdup_printf("%s/%s.%s", plugins->dir, name, G_MODULE_SUFFIX);
251 g_debug("GritsPlugins: load - trying %s", path);
252 if (!g_file_test(path, G_FILE_TEST_EXISTS)) {
254 path = g_strdup_printf("%s/%s.%s", PLUGINSDIR, name, G_MODULE_SUFFIX);
256 g_debug("GritsPlugins: load - trying %s", path);
257 if (!g_file_test(path, G_FILE_TEST_EXISTS)) {
258 g_warning("Module %s not found", name);
262 GModule *module = g_module_open(path, G_MODULE_BIND_LAZY);
264 if (module == NULL) {
265 g_warning("Unable to load module %s: %s", name, g_module_error());
269 gpointer constructor_ptr; // GCC 4.1 fix?
270 gchar *constructor_str = g_strconcat("grits_plugin_", name, "_new", NULL);
271 if (!g_module_symbol(module, constructor_str, &constructor_ptr)) {
272 g_warning("Unable to load symbol %s from %s: %s",
273 constructor_str, name, g_module_error());
274 g_module_close(module);
275 g_free(constructor_str);
278 g_free(constructor_str);
279 GritsPluginConstructor constructor = constructor_ptr;
281 GritsPluginStore *store = g_new0(GritsPluginStore, 1);
282 store->name = g_strdup(name);
283 store->plugin = constructor(viewer, prefs);
284 store->module = module;
285 plugins->plugins = g_list_prepend(plugins->plugins, store);
286 return store->plugin;
290 * grits_plugins_enable:
291 * @plugins: the plugins source
292 * @name: the name of the plugin to load
293 * @viewer: a #GritsViewer to pass to the plugins constructor
294 * @prefs: a #GritsPrefs to pass to the plugins constructor
296 * Load a plugin and save it's loaded/unloaded state in the #GritsPrefs stored in
299 * See also: grits_plugins_load()
301 * Returns: the new plugin
303 GritsPlugin *grits_plugins_enable(GritsPlugins *plugins, const char *name,
304 GritsViewer *viewer, GritsPrefs *prefs)
306 GritsPlugin *plugin = grits_plugins_load(plugins, name, viewer, prefs);
307 grits_prefs_set_boolean_v(plugins->prefs, "plugins", name, TRUE);
312 * grits_plugins_load_enabled:
313 * @plugins: the plugins source
314 * @viewer: a #GritsViewer to pass to the plugins constructor
315 * @prefs: a #GritsPrefs to pass to the plugins constructor
317 * Load all enabled which have previously been enabled.
319 * See also: grits_plugins_load()
321 * Returns: a list of all loaded plugins
323 GList *grits_plugins_load_enabled(GritsPlugins *plugins,
324 GritsViewer *viewer, GritsPrefs *prefs)
326 GList *loaded = NULL;
327 for (GList *cur = grits_plugins_available(plugins); cur; cur = cur->next) {
328 gchar *name = cur->data;
329 if (grits_prefs_get_boolean_v(plugins->prefs, "plugins", name, NULL)) {
330 GritsPlugin *plugin = grits_plugins_load(plugins, name, viewer, prefs);
331 loaded = g_list_prepend(loaded, plugin);
338 * grits_plugins_unload:
339 * @plugins: the plugins source
340 * @name: the name of the plugin to unload
342 * Unload a plugin and free any associated data.
346 gboolean grits_plugins_unload(GritsPlugins *plugins, const char *name)
348 g_debug("GritsPlugins: unload %s", name);
349 for (GList *cur = plugins->plugins; cur; cur = cur->next) {
350 GritsPluginStore *store = cur->data;
351 if (g_str_equal(store->name, name)) {
352 grits_plugins_free_store(store);
353 plugins->plugins = g_list_delete_link(plugins->plugins, cur);
360 * grits_plugins_disable:
361 * @plugins: the plugins source
362 * @name: the name of the plugin to unload
364 * Unload a plugin and save it's loaded/unloaded state in the #GritsPrefs stored
367 * See also: grits_plugins_unload()
371 gboolean grits_plugins_disable(GritsPlugins *plugins, const char *name)
373 grits_prefs_set_boolean_v(plugins->prefs, "plugins", name, FALSE);
374 grits_plugins_unload(plugins, name);
379 * grits_plugins_foreach:
380 * @plugins: the plugins source
381 * @callback: a function to call on each plugin
382 * @user_data: user data to pass to the function
384 * Iterate over all plugins loaded by the plugins source
386 void grits_plugins_foreach(GritsPlugins *plugins, GCallback _callback, gpointer user_data)
388 g_debug("GritsPlugins: foreach");
391 typedef void (*CBFunc)(GritsPlugin *, const gchar *, gpointer);
392 CBFunc callback = (CBFunc)_callback;
393 for (GList *cur = plugins->plugins; cur; cur = cur->next) {
394 GritsPluginStore *store = cur->data;
395 callback(store->plugin, store->name, user_data);