hlswmaster/src/plugin.c

/***************************************************************************
 *   Copyright (C) 03/2005 by Olaf Rempel                                  *
 *   razzor@kopf-tisch.de                                                  *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/
#include <stdlib.h>
#include <dlfcn.h>
#include <pthread.h>

#include "hlswmaster.h"
#include "plugin.h"
#include "netpkt.h"
#include "list.h"

/* liste der geladenen plugins */
LIST_HEAD(plugin_list);

/* sichert die plugin list UND die plugins ab */
static pthread_mutex_t plugin_lock = PTHREAD_MUTEX_INITIALIZER;

/**
 * plugin_load()
 * laedt ein plugin
 *
 * @param char *name
 * @return false on error
 *
 * TODO: pfadname als parameter (config-file?)
 * TODO: referenz speichern? wo? wie?
 */
int plugin_load(char *name) {
	void *tmp;

	if (!(tmp = dlopen(name, RTLD_NOW)))
		log_print("unable to load plugin '%s'", name);

	return 1;
}

/**
 * plugin_unload()
 * entfernt ein plugin
 *
 * @param char *name
 * @return false on error
 *
 * TODO: implementieren? oder lieber nicht?
 */
int plugin_unload(char *name) {
	return 1;
}

/**
 * plugins_scan()
 * ruft die scan() Funktionen der Plugins auf (wenn vorhanden)
 *
 * @return true
 */
int plugins_scan(void) {
	struct hlswmaster_plugin *plugin;

	pthread_mutex_lock(&plugin_lock);
	list_for_each_entry(plugin, &plugin_list, list)
		if (plugin->scan && !plugin->scan())
			log_print("plugin %s: scan error", plugin->name);

	pthread_mutex_unlock(&plugin_lock);
	return 1;
}

/**
 * plugins_parse()
 * ruft die parse() Funktionen der Plugins auf (wenn vorhanden)
 * bis ein Plugin das Paket annimmt
 *
 * @param struct net_pkt *pkt
 * @return false wenn kein Plugin das Paket angenommen hat
 */
int plugins_parse(struct net_pkt *pkt) {
	struct hlswmaster_plugin *plugin;

	pthread_mutex_lock(&plugin_lock);
	list_for_each_entry(plugin, &plugin_list, list) {
		if (plugin->parse && plugin->parse(pkt)) {
			pthread_mutex_unlock(&plugin_lock);
			return 1;
		}
	}

	pthread_mutex_unlock(&plugin_lock);
	return 0;
}

/**
 * plugins_gc()
 * ruft die gc() Funktionen der Plugins auf (wenn vorhanden)
 *
 * @param unsigned long timeout
 * @return true
 *
 * TODO: wird noch nicht benutzt
 */
int plugins_gc(unsigned long timeout) {
	struct hlswmaster_plugin *plugin;

	pthread_mutex_lock(&plugin_lock);
	list_for_each_entry(plugin, &plugin_list, list)
		if (plugin->gc)
			plugin->gc(timeout);

	pthread_mutex_unlock(&plugin_lock);
	return 1;
}

/**
 * register_plugin()
 * wird von den Plugins beim laden (durch _init())aufgerufen
 *
 * @param struct hlswmaster_plugin *me
 */
void register_plugin(struct hlswmaster_plugin *me) {
	if (!me->init || (me->init(NULL))) {
		pthread_mutex_lock(&plugin_lock);
		list_add_tail((struct list_head *)me, &plugin_list);
		pthread_mutex_unlock(&plugin_lock);
	}
}

/**
 * register_plugin()
 * wird von den Plugins beim entfernen (durch fini) aufgerufen
 *
 * @param struct hlswmaster_plugin *me
 */
void unregister_plugin(struct hlswmaster_plugin *me) {
	pthread_mutex_lock(&plugin_lock);
	list_del((struct list_head *)me);
	pthread_mutex_unlock(&plugin_lock);

	if (me->fini)
		me->fini();
}