meta-plugin-manager: Only allow one plugin to be loaded

The "multiple plugins loaded at once" strategy was always a big fiction:
while it may be viable if you're super careful, it's fragile and requires
a bit of infrastructure that we would be better off without.

Note that for simplicity, we're keeping the MetaPluginManager, but it only
manages one plugin. A possible future cleanup would be to remove it entirely.

https://bugzilla.gnome.org/show_bug.cgi?id=676855
This commit is contained in:
Jasper St. Pierre 2012-04-05 01:29:39 -04:00
parent 574c0c3287
commit f9454e29db
7 changed files with 111 additions and 298 deletions

View File

@ -557,9 +557,7 @@ meta_compositor_manage_screen (MetaCompositor *compositor,
clutter_actor_hide (info->hidden_group);
info->plugin_mgr =
meta_plugin_manager_get (screen);
meta_plugin_manager_initialize (info->plugin_mgr);
info->plugin_mgr = meta_plugin_manager_new (screen);
/*
* Delay the creation of the overlay window as long as we can, to avoid

View File

@ -35,34 +35,32 @@
#include <clutter/x11/clutter-x11.h>
static GSList *plugin_types;
/*
* We have one "default plugin manager" that acts for the first screen,
* but also can be used before we open any screens, and additional
* plugin managers for each screen. (This is ugly. Probably we should
* have one plugin manager and only make the plugins per-screen.)
*/
static MetaPluginManager *default_plugin_manager;
static GType plugin_type = G_TYPE_NONE;
struct MetaPluginManager
{
MetaScreen *screen;
GList /* MetaPlugin */ *plugins; /* TODO -- maybe use hash table */
MetaPlugin *plugin;
};
void
meta_plugin_manager_set_plugin_type (GType gtype)
{
if (plugin_type != G_TYPE_NONE)
meta_fatal ("Mutter plugin already set: %s", g_type_name (plugin_type));
plugin_type = gtype;
}
/*
* Loads the given plugin.
*/
void
meta_plugin_manager_load (MetaPluginManager *plugin_mgr,
const gchar *plugin_name)
meta_plugin_manager_load (const gchar *plugin_name)
{
const gchar *dpath = MUTTER_PLUGIN_DIR "/";
gchar *path;
MetaModule *module;
GType plugin_type;
if (g_path_is_absolute (plugin_name))
path = g_strdup (plugin_name);
@ -81,159 +79,52 @@ meta_plugin_manager_load (MetaPluginManager *plugin_mgr,
exit (1);
}
plugin_type = meta_module_get_plugin_type (module);
meta_plugin_manager_register (plugin_mgr, plugin_type);
meta_plugin_manager_set_plugin_type (meta_module_get_plugin_type (module));
g_type_module_unuse (G_TYPE_MODULE (module));
g_free (path);
}
/*
* Registers the given plugin type
*/
void
meta_plugin_manager_register (MetaPluginManager *plugin_mgr,
GType plugin_type)
{
MetaPlugin *plugin;
plugin_types = g_slist_prepend (plugin_types, GSIZE_TO_POINTER (plugin_type));
plugin = g_object_new (plugin_type, NULL);
plugin_mgr->plugins = g_list_prepend (plugin_mgr->plugins, plugin);
}
void
meta_plugin_manager_initialize (MetaPluginManager *plugin_mgr)
{
GList *iter;
if (!plugin_mgr->plugins)
{
/*
* If no plugins are specified, load the default plugin.
*/
meta_plugin_manager_load (plugin_mgr, "default");
}
for (iter = plugin_mgr->plugins; iter; iter = iter->next)
{
MetaPlugin *plugin = (MetaPlugin*) iter->data;
MetaPluginClass *klass = META_PLUGIN_GET_CLASS (plugin);
g_object_set (plugin,
"screen", plugin_mgr->screen,
NULL);
if (klass->start)
klass->start (plugin);
}
}
static MetaPluginManager *
MetaPluginManager *
meta_plugin_manager_new (MetaScreen *screen)
{
MetaPluginManager *plugin_mgr;
MetaPlugin *plugin;
plugin_mgr = g_new0 (MetaPluginManager, 1);
plugin_mgr->screen = screen;
if (screen)
g_object_set_data (G_OBJECT (screen), "meta-plugin-manager", plugin_mgr);
plugin_mgr->plugin = plugin = g_object_new (plugin_type, "screen", screen, NULL);
META_PLUGIN_GET_CLASS (plugin)->start (plugin);
return plugin_mgr;
}
MetaPluginManager *
meta_plugin_manager_get_default (void)
{
if (!default_plugin_manager)
{
default_plugin_manager = meta_plugin_manager_new (NULL);
}
return default_plugin_manager;
}
MetaPluginManager *
meta_plugin_manager_get (MetaScreen *screen)
{
MetaPluginManager *plugin_mgr;
plugin_mgr = g_object_get_data (G_OBJECT (screen), "meta-plugin-manager");
if (plugin_mgr)
return plugin_mgr;
if (!default_plugin_manager)
meta_plugin_manager_get_default ();
if (!default_plugin_manager->screen)
{
/* The default plugin manager is so far unused, we can recycle it */
default_plugin_manager->screen = screen;
g_object_set_data (G_OBJECT (screen), "meta-plugin-manager", default_plugin_manager);
return default_plugin_manager;
}
else
{
GSList *iter;
GType plugin_type;
MetaPlugin *plugin;
plugin_mgr = meta_plugin_manager_new (screen);
for (iter = plugin_types; iter; iter = iter->next)
{
plugin_type = (GType)GPOINTER_TO_SIZE (iter->data);
plugin = g_object_new (plugin_type, "screen", screen, NULL);
plugin_mgr->plugins = g_list_prepend (plugin_mgr->plugins, plugin);
}
return plugin_mgr;
}
}
static void
meta_plugin_manager_kill_window_effects (MetaPluginManager *plugin_mgr,
MetaWindowActor *actor)
{
GList *l = plugin_mgr->plugins;
while (l)
{
MetaPlugin *plugin = l->data;
MetaPlugin *plugin = plugin_mgr->plugin;
MetaPluginClass *klass = META_PLUGIN_GET_CLASS (plugin);
if (klass->kill_window_effects)
klass->kill_window_effects (plugin, actor);
l = l->next;
}
}
static void
meta_plugin_manager_kill_switch_workspace (MetaPluginManager *plugin_mgr)
{
GList *l = plugin_mgr->plugins;
while (l)
{
MetaPlugin *plugin = l->data;
MetaPlugin *plugin = plugin_mgr->plugin;
MetaPluginClass *klass = META_PLUGIN_GET_CLASS (plugin);
if (klass->kill_switch_workspace)
klass->kill_switch_workspace (plugin);
l = l->next;
}
}
/*
* Public method that the compositor hooks into for events that require
* no additional parameters.
*
* Returns TRUE if at least one of the plugins handled the event type (i.e.,
* Returns TRUE if the plugin handled the event type (i.e.,
* if the return value is FALSE, there will be no subsequent call to the
* manager completed() callback, and the compositor must ensure that any
* appropriate post-effect cleanup is carried out.
@ -243,18 +134,14 @@ meta_plugin_manager_event_simple (MetaPluginManager *plugin_mgr,
MetaWindowActor *actor,
unsigned long event)
{
GList *l = plugin_mgr->plugins;
gboolean retval = FALSE;
MetaPlugin *plugin = plugin_mgr->plugin;
MetaPluginClass *klass = META_PLUGIN_GET_CLASS (plugin);
MetaDisplay *display = meta_screen_get_display (plugin_mgr->screen);
gboolean retval = FALSE;
if (display->display_opening)
return FALSE;
while (l)
{
MetaPlugin *plugin = l->data;
MetaPluginClass *klass = META_PLUGIN_GET_CLASS (plugin);
switch (event)
{
case META_PLUGIN_MINIMIZE:
@ -291,9 +178,6 @@ meta_plugin_manager_event_simple (MetaPluginManager *plugin_mgr,
g_warning ("Incorrect handler called for event %lu", event);
}
l = l->next;
}
return retval;
}
@ -301,7 +185,7 @@ meta_plugin_manager_event_simple (MetaPluginManager *plugin_mgr,
* The public method that the compositor hooks into for maximize and unmaximize
* events.
*
* Returns TRUE if at least one of the plugins handled the event type (i.e.,
* Returns TRUE if the plugin handled the event type (i.e.,
* if the return value is FALSE, there will be no subsequent call to the
* manager completed() callback, and the compositor must ensure that any
* appropriate post-effect cleanup is carried out.
@ -315,18 +199,14 @@ meta_plugin_manager_event_maximize (MetaPluginManager *plugin_mgr,
gint target_width,
gint target_height)
{
GList *l = plugin_mgr->plugins;
gboolean retval = FALSE;
MetaPlugin *plugin = plugin_mgr->plugin;
MetaPluginClass *klass = META_PLUGIN_GET_CLASS (plugin);
MetaDisplay *display = meta_screen_get_display (plugin_mgr->screen);
gboolean retval = FALSE;
if (display->display_opening)
return FALSE;
while (l)
{
MetaPlugin *plugin = l->data;
MetaPluginClass *klass = META_PLUGIN_GET_CLASS (plugin);
switch (event)
{
case META_PLUGIN_MAXIMIZE:
@ -359,16 +239,13 @@ meta_plugin_manager_event_maximize (MetaPluginManager *plugin_mgr,
g_warning ("Incorrect handler called for event %lu", event);
}
l = l->next;
}
return retval;
}
/*
* The public method that the compositor hooks into for desktop switching.
*
* Returns TRUE if at least one of the plugins handled the event type (i.e.,
* Returns TRUE if the plugin handled the event type (i.e.,
* if the return value is FALSE, there will be no subsequent call to the
* manager completed() callback, and the compositor must ensure that any
* appropriate post-effect cleanup is carried out.
@ -379,18 +256,14 @@ meta_plugin_manager_switch_workspace (MetaPluginManager *plugin_mgr,
gint to,
MetaMotionDirection direction)
{
GList *l = plugin_mgr->plugins;
gboolean retval = FALSE;
MetaPlugin *plugin = plugin_mgr->plugin;
MetaPluginClass *klass = META_PLUGIN_GET_CLASS (plugin);
MetaDisplay *display = meta_screen_get_display (plugin_mgr->screen);
gboolean retval = FALSE;
if (display->display_opening)
return FALSE;
while (l)
{
MetaPlugin *plugin = l->data;
MetaPluginClass *klass = META_PLUGIN_GET_CLASS (plugin);
if (klass->switch_workspace)
{
retval = TRUE;
@ -400,16 +273,13 @@ meta_plugin_manager_switch_workspace (MetaPluginManager *plugin_mgr,
klass->switch_workspace (plugin, from, to, direction);
}
l = l->next;
}
return retval;
}
/*
* The public method that the compositor hooks into for desktop switching.
*
* Returns TRUE if at least one of the plugins handled the event type (i.e.,
* Returns TRUE if the plugin handled the event type (i.e.,
* if the return value is FALSE, there will be no subsequent call to the
* manager completed() callback, and the compositor must ensure that any
* appropriate post-effect cleanup is carried out.
@ -418,49 +288,20 @@ gboolean
meta_plugin_manager_xevent_filter (MetaPluginManager *plugin_mgr,
XEvent *xev)
{
GList *l;
gboolean have_plugin_xevent_func;
MetaPlugin *plugin = plugin_mgr->plugin;
MetaPluginClass *klass = META_PLUGIN_GET_CLASS (plugin);
if (!plugin_mgr)
return FALSE;
l = plugin_mgr->plugins;
/* We need to make sure that clutter gets certain events, like
* ConfigureNotify on the stage window. If there is a plugin that
* provides an xevent_filter function, then it's the responsibility
* of that plugin to pass events to Clutter. Otherwise, we send the
* event directly to Clutter ourselves.
*
* What happens if there are two plugins with xevent_filter functions
* is undefined; in general, multiple competing plugins are something
* we don't support well or care much about.
*
* FIXME: Really, we should just always handle sending the event to
* clutter if a plugin doesn't report the event as handled by
* returning TRUE, but it doesn't seem worth breaking compatibility
* of the plugin interface right now to achieve this; the way it is
* now works fine in practice.
*/
have_plugin_xevent_func = FALSE;
while (l)
{
MetaPlugin *plugin = l->data;
MetaPluginClass *klass = META_PLUGIN_GET_CLASS (plugin);
if (klass->xevent_filter)
{
have_plugin_xevent_func = TRUE;
if (klass->xevent_filter (plugin, xev) == TRUE)
if (klass->xevent_filter && klass->xevent_filter (plugin, xev))
return TRUE;
}
l = l->next;
}
if (!have_plugin_xevent_func)
else
return clutter_x11_handle_event (xev) != CLUTTER_X11_FILTER_CONTINUE;
return FALSE;
}

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@ -46,14 +46,9 @@
*/
typedef struct MetaPluginManager MetaPluginManager;
MetaPluginManager * meta_plugin_manager_get (MetaScreen *screen);
MetaPluginManager * meta_plugin_manager_get_default (void);
MetaPluginManager * meta_plugin_manager_new (MetaScreen *screen);
void meta_plugin_manager_load (MetaPluginManager *mgr,
const gchar *plugin_name);
void meta_plugin_manager_register (MetaPluginManager *mgr,
GType plugin_type);
void meta_plugin_manager_initialize (MetaPluginManager *mgr);
void meta_plugin_manager_load (const gchar *plugin_name);
gboolean meta_plugin_manager_event_simple (MetaPluginManager *mgr,
MetaWindowActor *actor,

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@ -52,7 +52,6 @@ struct _MetaPluginPrivate
MetaScreen *screen;
gint running;
gboolean debug : 1;
};
@ -332,19 +331,3 @@ meta_plugin_get_screen (MetaPlugin *plugin)
return priv->screen;
}
/**
* meta_plugin_type_register:
* @plugin_type: a #MetaPlugin type
*
* Register @plugin_type as a compositor plugin type to be used.
* You must call this before calling meta_init().
*/
void
meta_plugin_type_register (GType plugin_type)
{
MetaPluginManager *plugin_manager;
plugin_manager = meta_plugin_manager_get_default ();
meta_plugin_manager_register (plugin_manager, plugin_type);
}

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@ -373,7 +373,7 @@ on_sigterm (void)
* meta_init: (skip)
*
* Initialize mutter. Call this after meta_get_option_context() and
* meta_plugin_type_register(), and before meta_run().
* meta_plugin_manager_set_plugin_type(), and before meta_run().
*/
void
meta_init (void)

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@ -80,11 +80,7 @@ main (int argc, char **argv)
}
if (plugin)
{
MetaPluginManager *mgr;
mgr = meta_plugin_manager_get_default ();
meta_plugin_manager_load (mgr, plugin);
}
meta_plugin_manager_load (plugin);
meta_init ();
return meta_run ();

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@ -218,9 +218,6 @@ struct _MetaPluginVersion
return object_name##_register_type (type_module); \
} \
void
meta_plugin_type_register (GType plugin_type);
void
meta_plugin_switch_workspace_completed (MetaPlugin *plugin);
@ -274,4 +271,7 @@ MetaScreen *meta_plugin_get_screen (MetaPlugin *plugin);
void
_meta_plugin_effect_started (MetaPlugin *plugin);
/* XXX: Putting this in here so it's in the public header. */
void meta_plugin_manager_set_plugin_type (GType gtype);
#endif /* META_PLUGIN_H_ */