hlswmaster/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 <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <dlfcn.h>

#include "plugin.h"
#include "configfile.h"
#include "logging.h"
#include "netpkt.h"
#include "list.h"
#include "event.h"

#define BUFSIZE 512

static LIST_HEAD(plugin_list);

static int plugin_load(const char *filename, void *privdata)
{
	char *plugin_dir = (char *)privdata;

	char *fullname = malloc(BUFSIZE);
	if (fullname == NULL) {
		log_print(LOG_ERROR, "plugin_load: out of memory");
		return -1;
	}

	int len = snprintf(fullname, BUFSIZE, "%s/%s", plugin_dir, filename);
	if (len < 0 || len >= BUFSIZE) {
		log_print(LOG_ERROR, "plugin_load: file name too long: %s/%s", plugin_dir, filename);
		free(fullname);
		return -1;
	}

	dlerror();
	void *dlref = dlopen(fullname, RTLD_NOW);
	if (dlref == NULL) {
		log_print(LOG_WARN, "plugin_load: %s", dlerror());
		free(fullname);
		return -1;
	}

	struct hlswmaster_plugin *plugin = dlsym(dlref, "plugin");
	if (plugin == NULL) {
		log_print(LOG_WARN, "plugin_load: invalid plugin '%s'", fullname);
		dlclose(dlref);
		free(fullname);
		return -1;
	}

	log_print(LOG_INFO, "loading plugin '%s'", plugin->name);

	if (plugin->init == NULL || (plugin->init() == 0)) {
		list_add_tail(&plugin->list, &plugin_list);
		free(fullname);
		return 0;
	}

	log_print(LOG_WARN, "plugin_load: failed to load '%s'", plugin->name);
	dlclose(dlref);
	free(fullname);
	return -1;
}

int plugins_scan(void)
{
	struct hlswmaster_plugin *plugin;
	list_for_each_entry(plugin, &plugin_list, list)
		if (plugin->scan && !plugin->scan())
			log_print(LOG_WARN, "plugin %s: scan error", plugin->name);

	return 0;
}

int plugins_parse(struct net_pkt *pkt)
{
	int retval;

	struct hlswmaster_plugin *plugin;
	list_for_each_entry(plugin, &plugin_list, list)
		if (plugin->parse && (retval = plugin->parse(pkt)))
			return retval;

	return PARSE_REJECT;
}

int plugin_init(void)
{
	char *dir = config_get_string("global", "plugin_dir", ".");
	int cnt = config_get_strings("global", "plugin", plugin_load, (void *)dir);

	log_print(LOG_INFO, "%d plugins loaded", cnt);
	return 0;
}