Allow mutter to be used as a library

Move all of the mutter code into a new libmutter-wm.so, split its
main() method into meta_get_option_context(), meta_init() and
meta_run(), add methods for using in-process plugins, and add
libmutter-wm.pc pointing to the new library.

The mutter binary is now just a tiny program that links against
libmutter-wm. The --version and --mutter-plugins options are handled
at the mutter level, not in libmutter-wm, and a few strange unused
command-line options (--no-force-fullscreen and --no-tab-popup) have
been removed.

https://bugzilla.gnome.org/show_bug.cgi?id=643959

3 files changed, 55 insertions, 18 deletions

diff --git a/src/compositor/meta-plugin-manager.c b/src/compositor/meta-plugin-manager.c
index 13171ffaf..1001a01d8 100644
--- a/src/compositor/meta-plugin-manager.c
+++ b/src/compositor/meta-plugin-manager.c
@@ -63,7 +63,6 @@ meta_plugin_manager_load (MetaPluginManager *plugin_mgr,
   gchar       *path;
   MetaModule  *module;
   GType        plugin_type;
-  MetaPlugin  *plugin;
 
   if (g_path_is_absolute (plugin_name))
     path = g_strdup (plugin_name);
@@ -83,13 +82,25 @@ meta_plugin_manager_load (MetaPluginManager *plugin_mgr,
     }
 
   plugin_type = meta_module_get_plugin_type (module);
+  meta_plugin_manager_register (plugin_mgr, plugin_type);
+
+  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);
-
-  g_type_module_unuse (G_TYPE_MODULE (module));
-  g_free (path);
 }
 
 void
diff --git a/src/compositor/meta-plugin-manager.h b/src/compositor/meta-plugin-manager.h
index 888f2e890..ec09bdd45 100644
--- a/src/compositor/meta-plugin-manager.h
+++ b/src/compositor/meta-plugin-manager.h
@@ -51,6 +51,8 @@ MetaPluginManager * meta_plugin_manager_get_default (void);
 
 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);
 
 gboolean meta_plugin_manager_event_simple (MetaPluginManager *mgr,
diff --git a/src/compositor/meta-plugin.c b/src/compositor/meta-plugin.c
index a7786ffa8..b8af4423e 100644
--- a/src/compositor/meta-plugin.c
+++ b/src/compositor/meta-plugin.c
@@ -22,6 +22,7 @@
  */
 
 #include "meta-plugin.h"
+#include "meta-plugin-manager.h"
 #include "screen.h"
 #include "display.h"
 
@@ -60,18 +61,6 @@ struct _MetaPluginPrivate
 };
 
 static void
-meta_plugin_dispose (GObject *object)
-{
-  G_OBJECT_CLASS (meta_plugin_parent_class)->dispose (object);
-}
-
-static void
-meta_plugin_finalize (GObject *object)
-{
-  G_OBJECT_CLASS (meta_plugin_parent_class)->finalize (object);
-}
-
-static void
 meta_plugin_set_features (MetaPlugin *plugin)
 {
   MetaPluginPrivate  *priv     = plugin->priv;
@@ -103,6 +92,27 @@ meta_plugin_set_features (MetaPlugin *plugin)
 }
 
 static void
+meta_plugin_constructed (GObject *object)
+{
+  meta_plugin_set_features (META_PLUGIN (object));
+
+  if (G_OBJECT_CLASS (meta_plugin_parent_class)->constructed)
+      G_OBJECT_CLASS (meta_plugin_parent_class)->constructed (object);
+}
+
+static void
+meta_plugin_dispose (GObject *object)
+{
+  G_OBJECT_CLASS (meta_plugin_parent_class)->dispose (object);
+}
+
+static void
+meta_plugin_finalize (GObject *object)
+{
+  G_OBJECT_CLASS (meta_plugin_parent_class)->finalize (object);
+}
+
+static void
 meta_plugin_set_property (GObject      *object,
                           guint         prop_id,
                           const GValue *value,
@@ -161,6 +171,7 @@ meta_plugin_class_init (MetaPluginClass *klass)
 {
   GObjectClass      *gobject_class = G_OBJECT_CLASS (klass);
 
+  gobject_class->constructed     = meta_plugin_constructed;
   gobject_class->finalize        = meta_plugin_finalize;
   gobject_class->dispose         = meta_plugin_dispose;
   gobject_class->set_property    = meta_plugin_set_property;
@@ -207,8 +218,6 @@ meta_plugin_init (MetaPlugin *self)
   MetaPluginPrivate *priv;
 
   self->priv = priv = META_PLUGIN_GET_PRIVATE (self);
-
-  meta_plugin_set_features (self);
 }
 
 gulong
@@ -540,3 +549,18 @@ 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);
+}