Add support for embedded C plugins

This adds the new key Embedded to the .plugin
file which specifies the function to call instead
of peas_register_types to perform that same job.

https://bugzilla.gnome.org/show_bug.cgi?id=721693

6 files changed, 241 insertions, 44 deletions

diff --git a/libpeas/peas-engine.c b/libpeas/peas-engine.c
index 4a2782b..ccee8a6 100644
--- a/libpeas/peas-engine.c
+++ b/libpeas/peas-engine.c
@@ -161,10 +161,10 @@ load_plugin_info (PeasEngine  *engine,
 }
 
 static void
-load_dir_real (PeasEngine  *engine,
-               const gchar *module_dir,
-               const gchar *data_dir,
-               guint        recursions)
+load_file_dir_real (PeasEngine  *engine,
+                    const gchar *module_dir,
+                    const gchar *data_dir,
+                    guint        recursions)
 {
   GError *error = NULL;
   GDir *d;
@@ -188,7 +188,7 @@ load_dir_real (PeasEngine  *engine,
       if (g_file_test (filename, G_FILE_TEST_IS_DIR))
         {
           if (recursions > 0)
-            load_dir_real (engine, filename, data_dir, recursions - 1);
+            load_file_dir_real (engine, filename, data_dir, recursions - 1);
         }
       else if (g_str_has_suffix (dirent, ".plugin"))
         {
@@ -201,6 +201,67 @@ load_dir_real (PeasEngine  *engine,
   g_dir_close (d);
 }
 
+static void
+load_resource_dir_real (PeasEngine  *engine,
+                        const gchar *module_dir,
+                        const gchar *data_dir,
+                        guint        recursions)
+{
+  guint i;
+  const gchar *module_path;
+  gchar **children;
+  GError *error = NULL;
+
+  g_debug ("Loading %s/*.plugin...", module_dir);
+
+  module_path = module_dir + strlen ("resource://");
+  children = g_resources_enumerate_children (module_path,
+                                             G_RESOURCE_LOOKUP_FLAGS_NONE,
+                                             &error);
+
+  if (error != NULL)
+    {
+      g_debug ("%s", error->message);
+      g_error_free (error);
+      return;
+    }
+
+  for (i = 0; children[i] != NULL; ++i)
+    {
+      gboolean is_dir;
+      gchar *child;
+
+      is_dir = g_str_has_suffix (children[i], "/");
+
+      if (is_dir && recursions == 0)
+        continue;
+
+      if (!is_dir && !g_str_has_suffix (children[i], ".plugin"))
+        continue;
+
+      child = g_build_path ("/", module_dir, children[i], NULL);
+
+      if (is_dir)
+        load_resource_dir_real (engine, child, data_dir, recursions - 1);
+      else
+        load_plugin_info (engine, child, module_dir, data_dir);
+
+      g_free (child);
+    }
+
+  g_strfreev (children);
+}
+
+static void
+load_dir_real (PeasEngine *engine,
+               SearchPath *sp)
+{
+  if (!g_str_has_prefix (sp->module_dir, "resource://"))
+    load_file_dir_real (engine, sp->module_dir, sp->data_dir, 1);
+  else
+    load_resource_dir_real (engine, sp->module_dir, sp->data_dir, 1);
+}
+
 /**
  * peas_engine_rescan_plugins:
  * @engine: A #PeasEngine.
@@ -229,10 +290,7 @@ peas_engine_rescan_plugins (PeasEngine *engine)
 
   /* Go and read everything from the provided search paths */
   for (item = priv->search_paths; item != NULL; item = item->next)
-    {
-      SearchPath *sp = (SearchPath *) item->data;
-      load_dir_real (engine, sp->module_dir, sp->data_dir, 1);
-    }
+    load_dir_real (engine, (SearchPath *) item->data);
 
   g_object_thaw_notify (G_OBJECT (engine));
 }
@@ -256,7 +314,7 @@ peas_engine_insert_search_path (PeasEngine  *engine,
   priv->search_paths = g_list_insert (priv->search_paths, sp, position);
 
   g_object_freeze_notify (G_OBJECT (engine));
-  load_dir_real (engine, sp->module_dir, sp->data_dir, 1);
+  load_dir_real (engine, sp);
   g_object_thaw_notify (G_OBJECT (engine));
 }
 
diff --git a/libpeas/peas-object-module.c b/libpeas/peas-object-module.c
index a6ae729..fbd81f2 100644
--- a/libpeas/peas-object-module.c
+++ b/libpeas/peas-object-module.c
@@ -48,6 +48,7 @@ enum {
   PROP_0,
   PROP_MODULE_NAME,
   PROP_PATH,
+  PROP_SYMBOL,
   PROP_RESIDENT,
   PROP_LOCAL_LINKAGE,
   N_PROPERTIES
@@ -70,6 +71,7 @@ struct _PeasObjectModulePrivate {
 
   gchar *path;
   gchar *module_name;
+  gchar *symbol;
 
   guint resident : 1;
   guint local_linkage : 1;
@@ -91,27 +93,39 @@ peas_object_module_load (GTypeModule *gmodule)
 {
   PeasObjectModule *module = PEAS_OBJECT_MODULE (gmodule);
   PeasObjectModulePrivate *priv = GET_PRIV (module);
-  GModuleFlags flags = 0;
-  gchar *path;
-
-  if (priv->local_linkage)
-    flags = G_MODULE_BIND_LOCAL;
 
-  path = g_module_build_path (priv->path, priv->module_name);
-  g_return_val_if_fail (path != NULL, FALSE);
+  g_return_val_if_fail (priv->module_name != NULL, FALSE);
 
-  /* g_module_build_path() will add G_MODULE_SUFFIX to the path,
-   * however g_module_open() will only try to load the libtool archive
-   * if there is no suffix specified. So we remove G_MODULE_SUFFIX here
-   * which allows uninstalled builds to load plugins as well, as there
-   * is only the .la file in the build directory.
-   */
-  if (G_MODULE_SUFFIX[0] != '\0' && g_str_has_suffix (path, "." G_MODULE_SUFFIX))
-    path[strlen (path) - strlen (G_MODULE_SUFFIX) - 1] = '\0';
+  if (priv->path == NULL)
+    {
+      g_return_val_if_fail (priv->resident, FALSE);
+      g_return_val_if_fail (!priv->local_linkage, FALSE);
 
-  /* Bind symbols immediately to avoid errors long after loading */
-  priv->library = g_module_open (path, flags);
-  g_free (path);
+      priv->library = g_module_open (NULL, 0);
+    }
+  else
+    {
+      gchar *path;
+      GModuleFlags flags = 0;
+
+      path = g_module_build_path (priv->path, priv->module_name);
+
+      /* g_module_build_path() will add G_MODULE_SUFFIX to the path,
+       * however g_module_open() will only try to load the libtool archive
+       * if there is no suffix specified. So we remove G_MODULE_SUFFIX here
+       * which allows uninstalled builds to load plugins as well, as there
+       * is only the .la file in the build directory.
+       */
+      if (G_MODULE_SUFFIX[0] != '\0' && g_str_has_suffix (path, "." G_MODULE_SUFFIX))
+        path[strlen (path) - strlen (G_MODULE_SUFFIX) - 1] = '\0';
+
+      if (priv->local_linkage)
+        flags = G_MODULE_BIND_LOCAL;
+
+      /* Bind symbols immediately to avoid errors long after loading */
+      priv->library = g_module_open (path, flags);
+      g_free (path);
+    }
 
   if (priv->library == NULL)
     {
@@ -122,12 +136,11 @@ peas_object_module_load (GTypeModule *gmodule)
     }
 
   /* Extract the required symbol from the library */
-  if (!g_module_symbol (priv->library,
-                        "peas_register_types",
+  if (!g_module_symbol (priv->library, priv->symbol,
                         (gpointer) &priv->register_func))
     {
-      g_warning ("Failed to get 'peas_register_types' for module '%s': %s",
-                 priv->module_name, g_module_error ());
+      g_warning ("Failed to get '%s' for module '%s': %s",
+                 priv->symbol, priv->module_name, g_module_error ());
       g_module_close (priv->library);
 
       return FALSE;
@@ -138,8 +151,8 @@ peas_object_module_load (GTypeModule *gmodule)
    */
   if (priv->register_func == NULL)
     {
-      g_warning ("Invalid 'peas_register_types' in module '%s'",
-                 priv->module_name);
+      g_warning ("Invalid '%s' in module '%s'",
+                 priv->symbol, priv->module_name);
       g_module_close (priv->library);
 
       return FALSE;
@@ -194,6 +207,7 @@ peas_object_module_finalize (GObject *object)
 
   g_free (priv->path);
   g_free (priv->module_name);
+  g_free (priv->symbol);
   g_array_unref (priv->implementations);
 
   G_OBJECT_CLASS (peas_object_module_parent_class)->finalize (object);
@@ -216,6 +230,9 @@ peas_object_module_get_property (GObject    *object,
     case PROP_PATH:
       g_value_set_string (value, priv->path);
       break;
+    case PROP_SYMBOL:
+      g_value_set_string (value, priv->symbol);
+      break;
     case PROP_RESIDENT:
       g_value_set_boolean (value, priv->resident);
       break;
@@ -247,6 +264,9 @@ peas_object_module_set_property (GObject      *object,
     case PROP_PATH:
       priv->path = g_value_dup_string (value);
       break;
+    case PROP_SYMBOL:
+      priv->symbol = g_value_dup_string (value);
+      break;
     case PROP_RESIDENT:
       priv->resident = g_value_get_boolean (value);
       break;
@@ -292,6 +312,15 @@ peas_object_module_class_init (PeasObjectModuleClass *klass)
                          G_PARAM_CONSTRUCT_ONLY |
                          G_PARAM_STATIC_STRINGS);
 
+  properties[PROP_SYMBOL] =
+    g_param_spec_string ("symbol",
+                         "Symbol",
+                         "The registration symbol to use for this module",
+                         "peas_register_types",
+                         G_PARAM_READWRITE |
+                         G_PARAM_CONSTRUCT_ONLY |
+                         G_PARAM_STATIC_STRINGS);
+
   properties[PROP_RESIDENT] =
     g_param_spec_boolean ("resident",
                           "Resident",
@@ -377,6 +406,31 @@ peas_object_module_new_full (const gchar *module_name,
 }
 
 /**
+ * peas_object_module_new_embedded: (skip)
+ * @module_name: The module name.
+ *
+ * Creates a new #PeasObjectModule for an embedded plugin.
+ *
+ * Return value: a new #PeasObjectModule.
+ *
+ * Since: 1.18
+ */
+PeasObjectModule *
+peas_object_module_new_embedded (const gchar *module_name,
+                                 const gchar *symbol)
+{
+  g_return_val_if_fail (module_name != NULL && *module_name != '\0', NULL);
+  g_return_val_if_fail (symbol != NULL && *symbol != '\0', NULL);
+
+  return PEAS_OBJECT_MODULE (g_object_new (PEAS_TYPE_OBJECT_MODULE,
+                                           "module-name", module_name,
+                                           "symbol", symbol,
+                                           "resident", TRUE,
+                                           "local-linkage", FALSE,
+                                           NULL));
+}
+
+/**
  * peas_object_module_create_object: (skip)
  * @module: A #PeasObjectModule.
  * @interface: The #GType of the extension interface.
@@ -484,6 +538,26 @@ peas_object_module_get_module_name (PeasObjectModule *module)
 }
 
 /**
+ * peas_object_module_get_symbol: (skip)
+ * @module: A #PeasObjectModule.
+ *
+ * Gets the symbol name used to register extension implementations.
+ *
+ * Return value: the symbol name.
+ *
+ * Since: 1.18
+ */
+const gchar *
+peas_object_module_get_symbol (PeasObjectModule *module)
+{
+  PeasObjectModulePrivate *priv = GET_PRIV (module);
+
+  g_return_val_if_fail (PEAS_IS_OBJECT_MODULE (module), NULL);
+
+  return priv->symbol;
+}
+
+/**
  * peas_object_module_get_library: (skip)
  * @module: A #PeasObjectModule.
  *
diff --git a/libpeas/peas-object-module.h b/libpeas/peas-object-module.h
index 9f7e164..70a0265 100644
--- a/libpeas/peas-object-module.h
+++ b/libpeas/peas-object-module.h
@@ -91,6 +91,8 @@ PeasObjectModule   *peas_object_module_new_full               (const gchar
                                                                const gchar      *path,
                                                                gboolean          resident,
                                                                gboolean          local_linkage);
+PeasObjectModule   *peas_object_module_new_embedded           (const gchar      *module_name,
+                                                               const gchar      *symbol);
 
 GObject            *peas_object_module_create_object          (PeasObjectModule *module,
                                                                GType             interface,
@@ -101,6 +103,7 @@ gboolean            peas_object_module_provides_object        (PeasObjectModule
 
 const gchar        *peas_object_module_get_path               (PeasObjectModule *module);
 const gchar        *peas_object_module_get_module_name        (PeasObjectModule *module);
+const gchar        *peas_object_module_get_symbol             (PeasObjectModule *module);
 
 GModule            *peas_object_module_get_library            (PeasObjectModule *module);
 
diff --git a/libpeas/peas-plugin-info-priv.h b/libpeas/peas-plugin-info-priv.h
index e4b2fd3..2359df5 100644
--- a/libpeas/peas-plugin-info-priv.h
+++ b/libpeas/peas-plugin-info-priv.h
@@ -37,6 +37,7 @@ struct _PeasPluginInfo {
   gchar *data_dir;
 
   gint loader_id;
+  gchar *embedded;
   gchar *module_name;
   gchar **dependencies;
 
diff --git a/libpeas/peas-plugin-info.c b/libpeas/peas-plugin-info.c
index b30e82b..6fb7ce6 100644
--- a/libpeas/peas-plugin-info.c
+++ b/libpeas/peas-plugin-info.c
@@ -85,6 +85,7 @@ _peas_plugin_info_unref (PeasPluginInfo *info)
   g_free (info->filename);
   g_free (info->module_dir);
   g_free (info->data_dir);
+  g_free (info->embedded);
   g_free (info->module_name);
   g_strfreev (info->dependencies);
   g_free (info->name);
@@ -124,19 +125,42 @@ _peas_plugin_info_new (const gchar *filename,
                        const gchar *data_dir)
 {
   gsize i;
+  gboolean is_resource;
   gchar *loader = NULL;
   gchar **strv, **keys;
   PeasPluginInfo *info;
   GKeyFile *plugin_file;
+  GBytes *bytes = NULL;
   GError *error = NULL;
 
   g_return_val_if_fail (filename != NULL, NULL);
 
+  is_resource = g_str_has_prefix (filename, "resource://");
+
   info = g_new0 (PeasPluginInfo, 1);
   info->refcount = 1;
 
   plugin_file = g_key_file_new ();
-  if (!g_key_file_load_from_file (plugin_file, filename,
+  
+  if (is_resource)
+    {
+      bytes = g_resources_lookup_data (filename + strlen ("resource://"),
+                                       G_RESOURCE_LOOKUP_FLAGS_NONE,
+                                       &error);
+    }
+  else
+    {
+      gchar *content;
+      gsize length;
+
+      if (g_file_get_contents (filename, &content, &length, &error))
+        bytes = g_bytes_new_take (content, length);
+    }
+
+  if (bytes == NULL ||
+      !g_key_file_load_from_data (plugin_file,
+                                  g_bytes_get_data (bytes, NULL),
+                                  g_bytes_get_size (bytes),
                                   G_KEY_FILE_NONE, &error))
     {
       g_warning ("Bad plugin file '%s': %s", filename, error->message);
@@ -183,7 +207,31 @@ _peas_plugin_info_new (const gchar *filename,
         }
     }
 
-  g_free (loader);
+  /* Get Embedded */
+  info->embedded = g_key_file_get_string (plugin_file, "Plugin",
+                                          "Embedded", NULL);
+  if (info->embedded != NULL)
+    {
+      if (info->loader_id != PEAS_UTILS_C_LOADER_ID)
+        {
+          g_warning ("Bad plugin file '%s': embedded plugins "
+                     "must use the C plugin loader", filename);
+          goto error;
+        }
+
+      if (!is_resource)
+        {
+          g_warning ("Bad plugin file '%s': embedded plugins "
+                     "must be a resource", filename);
+          goto error;
+        }
+    }
+  else if (is_resource)
+    {
+      g_warning ("Bad plugin file '%s': resource plugins must be embedded",
+                 filename);
+      goto error;
+    }
 
   /* Get the dependency list */
   info->dependencies = g_key_file_get_string_list (plugin_file,
@@ -259,11 +307,14 @@ _peas_plugin_info_new (const gchar *filename,
 
   g_strfreev (keys);
 
+  g_free (loader);
+  g_bytes_unref (bytes);
   g_key_file_free (plugin_file);
 
   info->filename = g_strdup (filename);
   info->module_dir = g_strdup (module_dir);
-  info->data_dir = g_build_filename (data_dir, info->module_name, NULL);
+  info->data_dir = g_build_path (is_resource ? "/" : G_DIR_SEPARATOR_S,
+                                 data_dir, info->module_name, NULL);
 
   /* If we know nothing about the availability of the plugin,
      set it as available */
@@ -273,10 +324,12 @@ _peas_plugin_info_new (const gchar *filename,
 
 error:
 
+  g_free (info->embedded);
   g_free (loader);
   g_free (info->module_name);
   g_free (info->name);
   g_free (info);
+  g_clear_pointer (&bytes, g_bytes_unref);
   g_key_file_free (plugin_file);
 
   return NULL;
diff --git a/libpeas/peas-plugin-loader-c.c b/libpeas/peas-plugin-loader-c.c
index 59942d0..a476eb4 100644
--- a/libpeas/peas-plugin-loader-c.c
+++ b/libpeas/peas-plugin-loader-c.c
@@ -65,13 +65,21 @@ peas_plugin_loader_c_load (PeasPluginLoader *loader,
       module_name = peas_plugin_info_get_module_name (info);
       module_dir = peas_plugin_info_get_module_dir (info);
 
-      /* Force all C modules to be resident in case they
-       * use libraries that do not deal well with reloading.
-       * Furthermore, we use local linkage to improve module isolation.
-       */
-      info->loader_data = peas_object_module_new_full (module_name,
-                                                       module_dir,
-                                                       TRUE, TRUE);
+      if (info->embedded != NULL)
+        {
+          info->loader_data = peas_object_module_new_embedded (module_name,
+                                                               info->embedded);
+        }
+      else
+        {
+          /* Force all C modules to be resident in case they
+           * use libraries that do not deal well with reloading.
+           * Furthermore, we use local linkage to improve module isolation.
+           */
+          info->loader_data = peas_object_module_new_full (module_name,
+                                                           module_dir,
+                                                           TRUE, TRUE);
+        }
 
       if (!g_type_module_use (G_TYPE_MODULE (info->loader_data)))
         g_clear_object (&info->loader_data);