/***************************************************************************
 *   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 "configfile.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 shared object,
 * fuehrt wenn vorhanden init() aus
 * und haengt den plugin an das ende der liste
 *
 * @param char *name
 * @return false on error
 */
int plugin_load(char *name) {
	struct hlswmaster_plugin *plugin;
	void *tmp;
	struct conf_section *section;

	dlerror();

	if ((tmp = dlopen(name, RTLD_NOW))) {
		if ((plugin = dlsym(tmp, "plugin"))) {
			plugin->dlref = tmp;

			section = config_get_section(plugin->name);

			log_print("loading plugin '%s'", plugin->name);
			if (!plugin->init || (plugin->init(section))) {
				pthread_mutex_lock(&plugin_lock);
				list_add_tail(&plugin->list, &plugin_list);
				pthread_mutex_unlock(&plugin_lock);
				
				return 1;
			}
			log_print("failed to load '%s'", name);
			dlclose(tmp);
			return 0;
		}
		log_print("%s", dlerror());
		dlclose(tmp);
	}
	return 0;
}


/**
 * plugin_load_all()
 * laedt alle in der config angegebenen plugins
 *
 * @return false on error
 */
int plugin_load_all() {
	struct conf_section *section;
	struct conf_tupel *tupel;

	section = config_get_section("global");
	if (section) {
		list_for_each_entry(tupel, &section->tupel, list)
			if (!strcmp(tupel->option, "plugin"))
				plugin_load(tupel->parameter);
	}
	return 1;
}


/**
 * plugin_unload_all()
 * entfernt alle plugins aus der liste,
 * ruft wenn vorhanden fini() auf
 * und entlaed das shared object
 *
 * @return false on error
 */
int plugin_unload_all() {
	struct hlswmaster_plugin *plugin, *tmp;

	pthread_mutex_lock(&plugin_lock);
	list_for_each_entry_safe(plugin, tmp, &plugin_list, list) {
		list_del(&plugin->list);
		
		if (plugin->fini)
			plugin->fini();
		
		log_print("plugin '%s' unloaded", plugin->name);
		dlclose(plugin->dlref);
	}
	pthread_mutex_unlock(&plugin_lock);
	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, welcher thread soll das machen?
 */
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;
}