Added a method to plugin_loader_t to add 'static' plugin features

This allows daemons and other components to register plugin features
like those provided by plugins (following the same lifecycle).

The added features are internally handled like they were added by a
plugin.

2 files changed, 115 insertions, 0 deletions

diff --git a/src/libstrongswan/plugins/plugin_loader.c b/src/libstrongswan/plugins/plugin_loader.c
index d4c92468a..d5777e35b 100644
--- a/src/libstrongswan/plugins/plugin_loader.c
+++ b/src/libstrongswan/plugins/plugin_loader.c
@@ -105,6 +105,78 @@ static void plugin_entry_destroy(plugin_entry_t *entry)
 }
 
 /**
+ * Wrapper for static plugin features
+ */
+typedef struct {
+
+	/**
+	 * Implements plugin_t interface
+	 */
+	plugin_t public;
+
+	/**
+	 * Name of the module registering these features
+	 */
+	char *name;
+
+	/**
+	 * Static plugin features
+	 */
+	plugin_feature_t *features;
+
+	/**
+	 * Number of plugin features
+	 */
+	int count;
+
+} static_features_t;
+
+METHOD(plugin_t, get_static_name, char*,
+	static_features_t *this)
+{
+	return this->name;
+}
+
+METHOD(plugin_t, get_static_features, int,
+	static_features_t *this, plugin_feature_t *features[])
+{
+	*features = this->features;
+	return this->count;
+}
+
+METHOD(plugin_t, static_destroy, void,
+	static_features_t *this)
+{
+	free(this->features);
+	free(this->name);
+	free(this);
+}
+
+/**
+ * Create a wrapper around static plugin features.
+ */
+static plugin_t *static_features_create(const char *name,
+										plugin_feature_t features[], int count)
+{
+	static_features_t *this;
+
+	INIT(this,
+		.public = {
+			.get_name = _get_static_name,
+			.get_features = _get_static_features,
+			.destroy = _static_destroy,
+		},
+		.name = strdup(name),
+		.features = calloc(count, sizeof(plugin_feature_t)),
+		.count = count,
+	);
+
+	memcpy(this->features, features, sizeof(plugin_feature_t) * count);
+
+	return &this->public;
+}
+
+/**
  * Compare function for hashtable of loaded features.
  */
 static bool plugin_feature_equals(plugin_feature_t *a, plugin_feature_t *b)
@@ -554,6 +626,24 @@ static void purge_plugins(private_plugin_loader_t *this)
 	enumerator->destroy(enumerator);
 }
 
+METHOD(plugin_loader_t, add_static_features, void,
+	private_plugin_loader_t *this, const char *name,
+	plugin_feature_t features[], int count, bool critical)
+{
+	plugin_entry_t *entry;
+	plugin_t *plugin;
+
+	plugin = static_features_create(name, features, count);
+
+	INIT(entry,
+		.plugin = plugin,
+		.critical = critical,
+		.loaded = linked_list_create(),
+		.failed = linked_list_create(),
+	);
+	this->plugins->insert_last(this->plugins, entry);
+}
+
 METHOD(plugin_loader_t, load_plugins, bool,
 	private_plugin_loader_t *this, char *path, char *list)
 {
@@ -740,6 +830,7 @@ plugin_loader_t *plugin_loader_create()
 
 	INIT(this,
 		.public = {
+			.add_static_features = _add_static_features,
 			.load = _load_plugins,
 			.reload = _reload,
 			.unload = _unload,
diff --git a/src/libstrongswan/plugins/plugin_loader.h b/src/libstrongswan/plugins/plugin_loader.h
index 7fd07044d..94181dbb6 100644
--- a/src/libstrongswan/plugins/plugin_loader.h
+++ b/src/libstrongswan/plugins/plugin_loader.h
@@ -26,12 +26,36 @@ typedef struct plugin_loader_t plugin_loader_t;
 
 #include <utils/enumerator.h>
 
+/* to avoid circular references we can't include plugin_feature.h */
+struct plugin_feature_t;
+
 /**
  * The plugin_loader loads plugins from a directory and initializes them
  */
 struct plugin_loader_t {
 
 	/**
+	 * Add static plugin features, not loaded via plugins.
+	 *
+	 * Similar to features provided by plugins they are evaluated during load(),
+	 * and unloaded when unload() is called.
+	 *
+	 * If critical is TRUE load() will fail if any of the added features could
+	 * not be loaded.
+	 *
+	 * @note The name should be unique otherwise a plugin with the same name is
+	 * not loaded.
+	 *
+	 * @param name			name of the component adding the features
+	 * @param features		array of plugin features
+	 * @param count			number of features in the array
+	 * @param critical		TRUE if the features are critical
+	 */
+	void (*add_static_features) (plugin_loader_t *this, const char *name,
+								 struct plugin_feature_t *features, int count,
+								 bool critical);
+
+	/**
 	 * Load a list of plugins from a directory.
 	 *
 	 * Each plugin in list may have a ending exclamation mark (!) to mark it