/*
 *  ircd-ratbox: A slightly useful ircd.
 *  ircd.c: Starts up and runs the ircd.
 *
 *  Copyright (C) 1990 Jarkko Oikarinen and University of Oulu, Co Center
 *  Copyright (C) 1996-2002 Hybrid Development Team
 *  Copyright (C) 2002-2005 ircd-ratbox development team
 *
 *  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
 *
 *  $Id: ircd.c 3251 2007-03-05 18:58:38Z nenolod $
 */

#include "stdinc.h"
#include "setup.h"
#include "config.h"

#include "tools.h"
#include "ircd.h"
#include "channel.h"
#include "class.h"
#include "client.h"
#include "common.h"
#include "event.h"
#include "hash.h"
#include "irc_string.h"
#include "ircd_signal.h"
#include "sprintf_irc.h"
#include "s_gline.h"
#include "msg.h"		/* msgtab */
#include "hostmask.h"
#include "numeric.h"
#include "parse.h"
#include "res.h"
#include "restart.h"
#include "s_auth.h"
#include "commio.h"
#include "s_conf.h"
#include "s_log.h"
#include "s_serv.h"		/* try_connections */
#include "s_user.h"
#include "s_stats.h"
#include "scache.h"
#include "send.h"
#include "supported.h"
#include "whowas.h"
#include "modules.h"
#include "memory.h"
#include "hook.h"
#include "ircd_getopt.h"
#include "balloc.h"
#include "newconf.h"
#include "patricia.h"
#include "reject.h"
#include "s_conf.h"
#include "s_newconf.h"
#include "cache.h"
#include "monitor.h"
#include "libcharybdis.h"
#include "patchlevel.h"
#include "serno.h"

/*
 * Try and find the correct name to use with getrlimit() for setting the max.
 * number of files allowed to be open by this process.
 */
int _charybdis_data_version = CHARYBDIS_DV;

extern int ServerRunning;
extern struct LocalUser meLocalUser;
extern char **myargv;

/*
 * print_startup - print startup information
 */
static void
print_startup(int pid)
{
	inotice("now running in %s mode from %s as pid %d ...",
	       !server_state_foreground ? "background" : "foreground",
        	ConfigFileEntry.dpath, pid);

	/* let the parent process know the initialization was successful
	 * -- jilles */
	if (!server_state_foreground)
		write(0, ".", 1);
	fclose(stdin);
	fclose(stdout);
	fclose(stderr);
	open("/dev/null", O_RDWR);
	dup2(0, 1);
	dup2(0, 2);
}

static void
ircd_log_cb(const char *str)
{
	ilog(L_MAIN, "%s", str);
}

/*
 * Why EXIT_FAILURE here?
 * Because if ircd_die_cb() is called it's because of a fatal
 * error inside libcharybdis, and we don't know how to handle the
 * exception, so it is logical to return a FAILURE exit code here.
 *    --nenolod
 */
static void
ircd_die_cb(const char *str)
{
	/* Try to get the message out to currently logged in operators. */
	sendto_realops_snomask(SNO_GENERAL, L_NETWIDE, "Server panic! %s", str);
	inotice("server panic: %s", str);

	unlink(pidFileName);
	exit(EXIT_FAILURE);
}

/*
 * init_sys
 *
 * inputs	- boot_daemon flag
 * output	- none
 * side effects	- if boot_daemon flag is not set, don't daemonize
 */
static void
init_sys(void)
{
#if defined(RLIMIT_FD_MAX) && defined(HAVE_SYS_RLIMIT_H)
	struct rlimit limit;

	if(!getrlimit(RLIMIT_FD_MAX, &limit))
	{
		if(limit.rlim_max < MAXCONNECTIONS)
		{
			fprintf(stderr, "ircd's bootstrap fd table is too big\n");
			fprintf(stderr, "Hard Limit: %ld bootstrap size: %d\n",
				(long) limit.rlim_max, MAXCONNECTIONS);
			fprintf(stderr, "Fix MAXCONNECTIONS\n");
			exit(-1);
		}

		limit.rlim_cur = limit.rlim_max;	/* make soft limit the max */
		if(setrlimit(RLIMIT_FD_MAX, &limit) == -1)
		{
			fprintf(stderr, "error setting max fd's to %ld\n", (long) limit.rlim_cur);
			exit(EXIT_FAILURE);
		}
	}
#endif /* RLIMIT_FD_MAX */
}

static int
make_daemon(void)
{
	int pid;
	int pip[2];
	char c;

	if (pipe(pip) < 0)
	{
		perror("pipe");
		exit(EXIT_FAILURE);
	}
	dup2(pip[1], 0);
	close(pip[1]);
	if((pid = fork()) < 0)
	{
		perror("fork");
		exit(EXIT_FAILURE);
	}
	else if(pid > 0)
	{
		close(0);
		/* Wait for initialization to finish, successfully or
		 * unsuccessfully. Until this point the child may still
		 * write to stdout/stderr.
		 * -- jilles */
		if (read(pip[0], &c, 1) > 0)
			exit(EXIT_SUCCESS);
		else
			exit(EXIT_FAILURE);
	}

	close(pip[0]);
	setsid();
/*	fclose(stdin);
	fclose(stdout);
	fclose(stderr); */

	return 0;
}

static int printVersion = 0;

struct lgetopt myopts[] = {
	{"dlinefile", &ConfigFileEntry.dlinefile,
	 STRING, "File to use for dlines.conf"},
	{"configfile", &ConfigFileEntry.configfile,
	 STRING, "File to use for ircd.conf"},
	{"klinefile", &ConfigFileEntry.klinefile,
	 STRING, "File to use for kline.conf"},
	{"xlinefile", &ConfigFileEntry.xlinefile,
	 STRING, "File to use for xline.conf"},
	{"resvfile", &ConfigFileEntry.resvfile,
	 STRING, "File to use for resv.conf"},
	{"logfile", &logFileName,
	 STRING, "File to use for ircd.log"},
	{"pidfile", &pidFileName,
	 STRING, "File to use for process ID"},
	{"foreground", &server_state_foreground,
	 YESNO, "Run in foreground (don't detach)"},
	{"version", &printVersion,
	 YESNO, "Print version and exit"},
	{"conftest", &testing_conf,
	 YESNO, "Test the configuration files and exit"},
	{"help", NULL, USAGE, "Print this text"},
	{NULL, NULL, STRING, NULL},
};

void
set_time(void)
{
	struct timeval newtime;
	newtime.tv_sec = 0;
	newtime.tv_usec = 0;
#ifdef HAVE_GETTIMEOFDAY
	if(gettimeofday(&newtime, NULL) == -1)
	{
		ilog(L_MAIN, "Clock Failure (%d)", errno);
		sendto_realops_snomask(SNO_GENERAL, L_ALL,
				     "Clock Failure (%d), TS can be corrupted", errno);

		restart("Clock Failure");
	}
#else
	newtime.tv_sec = time(NULL);
	
#endif
	if(newtime.tv_sec < CurrentTime)
		set_back_events(CurrentTime - newtime.tv_sec);

	SystemTime.tv_sec = newtime.tv_sec;
	SystemTime.tv_usec = newtime.tv_usec;
}

static void
check_rehash(void *unused)
{
	/*
	 * Check to see whether we have to rehash the configuration ..
	 */
	if(dorehash)
	{
		rehash(1);
		dorehash = 0;
	}

	if(dorehashbans)
	{
		rehash_bans(1);
		dorehashbans = 0;
	}

	if(doremotd)
	{
		sendto_realops_snomask(SNO_GENERAL, L_ALL,
				     "Got signal SIGUSR1, reloading ircd motd file");
		free_cachefile(user_motd);
		user_motd = cache_file(MPATH, "ircd.motd", 0);
		doremotd = 0;
	}
}

void
charybdis_io_loop(void)
{
	time_t delay;

	while (ServerRunning)
	{
		/* Run pending events, then get the number of seconds to the next
		 * event
		 */

		delay = eventNextTime();
		if(delay <= CurrentTime)
			eventRun();


		comm_select(250);
	}
}

/*
 * initalialize_global_set_options
 *
 * inputs       - none
 * output       - none
 * side effects - This sets all global set options needed 
 */
static void
initialize_global_set_options(void)
{
	memset(&GlobalSetOptions, 0, sizeof(GlobalSetOptions));
	/* memset( &ConfigFileEntry, 0, sizeof(ConfigFileEntry)); */

	GlobalSetOptions.maxclients = ServerInfo.max_clients;
	GlobalSetOptions.autoconn = 1;

	GlobalSetOptions.spam_time = MIN_JOIN_LEAVE_TIME;
	GlobalSetOptions.spam_num = MAX_JOIN_LEAVE_COUNT;

	if(ConfigFileEntry.default_floodcount)
		GlobalSetOptions.floodcount = ConfigFileEntry.default_floodcount;
	else
		GlobalSetOptions.floodcount = 10;

	split_servers = ConfigChannel.default_split_server_count;
	split_users = ConfigChannel.default_split_user_count;

	if(split_users && split_servers
	   && (ConfigChannel.no_create_on_split || ConfigChannel.no_join_on_split))
	{
		splitmode = 1;
		splitchecking = 1;
	}

	GlobalSetOptions.ident_timeout = IDENT_TIMEOUT;

	strlcpy(GlobalSetOptions.operstring,
		ConfigFileEntry.default_operstring,
		sizeof(GlobalSetOptions.operstring));
	strlcpy(GlobalSetOptions.adminstring,
		ConfigFileEntry.default_adminstring,
		sizeof(GlobalSetOptions.adminstring));

	/* memset( &ConfigChannel, 0, sizeof(ConfigChannel)); */

	/* End of global set options */

}

/*
 * initialize_server_capabs
 *
 * inputs       - none
 * output       - none
 */
static void
initialize_server_capabs(void)
{
	default_server_capabs &= ~CAP_ZIP;
}


/*
 * write_pidfile
 *
 * inputs       - filename+path of pid file
 * output       - none
 * side effects - write the pid of the ircd to filename
 */
static void
write_pidfile(const char *filename)
{
	FILE *fb;
	char buff[32];
	if((fb = fopen(filename, "w")))
	{
		unsigned int pid = (unsigned int) getpid();

		ircsnprintf(buff, sizeof(buff), "%u\n", pid);
		if((fputs(buff, fb) == -1))
		{
			ilog(L_MAIN, "Error writing %u to pid file %s (%s)",
			     pid, filename, strerror(errno));
		}
		fclose(fb);
		return;
	}
	else
	{
		ilog(L_MAIN, "Error opening pid file %s", filename);
	}
}

/*
 * check_pidfile
 *
 * inputs       - filename+path of pid file
 * output       - none
 * side effects - reads pid from pidfile and checks if ircd is in process
 *                list. if it is, gracefully exits
 * -kre
 */
static void
check_pidfile(const char *filename)
{
	FILE *fb;
	char buff[32];
	pid_t pidfromfile;

	/* Don't do logging here, since we don't have log() initialised */
	if((fb = fopen(filename, "r")))
	{
		if(fgets(buff, 20, fb) != NULL)
		{
			pidfromfile = atoi(buff);
			if(!kill(pidfromfile, 0))
			{
				printf("ircd: daemon is already running\n");
				exit(-1);
			}
		}
		fclose(fb);
	}
}

/*
 * setup_corefile
 *
 * inputs       - nothing
 * output       - nothing
 * side effects - setups corefile to system limits.
 * -kre
 */
static void
setup_corefile(void)
{
#ifdef HAVE_SYS_RESOURCE_H
	struct rlimit rlim;	/* resource limits */

	/* Set corefilesize to maximum */
	if(!getrlimit(RLIMIT_CORE, &rlim))
	{
		rlim.rlim_cur = rlim.rlim_max;
		setrlimit(RLIMIT_CORE, &rlim);
	}
#endif
}

/*
 * main
 *
 * Initializes the IRCd.
 *
 * Inputs       - number of commandline args, args themselves
 * Outputs      - none
 * Side Effects - this is where the ircd gets going right now
 */
int
main(int argc, char *argv[])
{
	int fd;

	/* Check to see if the user is running us as root, which is a nono */
	if(geteuid() == 0)
	{
		fprintf(stderr, "Don't run ircd as root!!!\n");
		return -1;
	}

	/*
	 * save server boot time right away, so getrusage works correctly
	 */
	set_time();
	/*
	 * Setup corefile size immediately after boot -kre
	 */
	setup_corefile();

	ServerRunning = 0;
	/* It ain't random, but it ought to be a little harder to guess */
	srand(SystemTime.tv_sec ^ (SystemTime.tv_usec | (getpid() << 20)));
	memset(&me, 0, sizeof(me));
	memset(&meLocalUser, 0, sizeof(meLocalUser));
	me.localClient = &meLocalUser;

	/* Make sure all lists are zeroed */
	memset(&unknown_list, 0, sizeof(unknown_list));
	memset(&lclient_list, 0, sizeof(lclient_list));
	memset(&serv_list, 0, sizeof(serv_list));
	memset(&global_serv_list, 0, sizeof(global_serv_list));
	memset(&local_oper_list, 0, sizeof(local_oper_list));
	memset(&oper_list, 0, sizeof(oper_list));

	dlinkAddTail(&me, &me.node, &global_client_list);

	memset((void *) &Count, 0, sizeof(Count));
	memset((void *) &ServerInfo, 0, sizeof(ServerInfo));
	memset((void *) &AdminInfo, 0, sizeof(AdminInfo));

	/* Initialise the channel capability usage counts... */
	init_chcap_usage_counts();

	ConfigFileEntry.dpath = DPATH;
	ConfigFileEntry.configfile = CPATH;	/* Server configuration file */
	ConfigFileEntry.klinefile = KPATH;	/* Server kline file */
	ConfigFileEntry.dlinefile = DLPATH;	/* dline file */
	ConfigFileEntry.xlinefile = XPATH;
	ConfigFileEntry.resvfile = RESVPATH;
	ConfigFileEntry.connect_timeout = 30;	/* Default to 30 */
	myargv = argv;
	umask(077);		/* better safe than sorry --SRB */

	parseargs(&argc, &argv, myopts);

	if(printVersion)
	{
		printf("ircd: version %s\n", ircd_version);
		exit(EXIT_SUCCESS);
	}

	if(chdir(ConfigFileEntry.dpath))
	{
		fprintf(stderr, "Unable to chdir to %s: %s\n", ConfigFileEntry.dpath, strerror(errno));
		exit(EXIT_FAILURE);
	}

	setup_signals();

#ifdef __CYGWIN__
	server_state_foreground = 1;
#endif

	if (testing_conf)
		server_state_foreground = 1;

	/* Make sure fd 0, 1 and 2 are in use -- jilles */
	do
	{
		fd = open("/dev/null", O_RDWR);
	} while (fd < 2 && fd != -1);
	if (fd > 2)
		close(fd);
	else if (fd == -1)
		exit(1);

	/* Check if there is pidfile and daemon already running */
	if(!testing_conf)
	{
		check_pidfile(pidFileName);

		if(!server_state_foreground)
			make_daemon();
		inotice("starting %s ...", ircd_version);
	}

	/* Init the event subsystem */
	libcharybdis_init(ircd_log_cb, restart, ircd_die_cb);
	init_sys();

	fdlist_init();
	if(!server_state_foreground)
	{
		comm_close_all();
	}

	init_main_logfile();
	init_patricia();
	newconf_init();
	init_s_conf();
	init_s_newconf();
	init_hash();
	clear_scache_hash_table();	/* server cache name table */
	init_host_hash();
	clear_hash_parse();
	init_client();
	initUser();
	init_hook();
	init_channels();
	initclass();
	initwhowas();
	init_stats();
	init_reject();
	init_cache();
	init_monitor();
	init_isupport();
	load_all_modules(1);
#ifndef STATIC_MODULES
	load_core_modules(1);
#endif
	init_auth();		/* Initialise the auth code */
	init_resolver();	/* Needs to be setup before the io loop */

	if (testing_conf)
		fprintf(stderr, "\nBeginning config test\n");
	read_conf_files(YES);	/* cold start init conf files */
	rehash_bans(0);
#ifndef STATIC_MODULES

	mod_add_path(MODULE_DIR); 
	mod_add_path(MODULE_DIR "/autoload"); 
#endif

	initialize_server_capabs();	/* Set up default_server_capabs */
	initialize_global_set_options();

	if(ServerInfo.name == NULL)
	{
		ierror("no server name specified in serverinfo block.");
		return -1;
	}
	strlcpy(me.name, ServerInfo.name, sizeof(me.name));

	if(ServerInfo.sid[0] == '\0')
	{
		ierror("no server sid specified in serverinfo block.");
		return -2;
	}
	strcpy(me.id, ServerInfo.sid);
	init_uid();

	/* serverinfo{} description must exist.  If not, error out. */
	if(ServerInfo.description == NULL)
	{
		ierror("no server description specified in serverinfo block.");
		return -3;
	}
	strlcpy(me.info, ServerInfo.description, sizeof(me.info));

	if (testing_conf)
	{
		fprintf(stderr, "\nConfig testing complete.\n");
		fflush(stderr);
		return 0;	/* Why? We want the launcher to exit out. */
	}

	me.from = &me;
	me.servptr = &me;
	SetMe(&me);
	make_server(&me);
	me.serv->up = me.name;
	startup_time = CurrentTime;
	add_to_client_hash(me.name, &me);
	add_to_id_hash(me.id, &me);

	dlinkAddAlloc(&me, &global_serv_list);

	construct_umodebuf();

	check_class();
	write_pidfile(pidFileName);
	load_help();
	open_logfiles();

	ilog(L_MAIN, "Server Ready");

	eventAddIsh("cleanup_glines", cleanup_glines, NULL, CLEANUP_GLINES_TIME);

	/* We want try_connections to be called as soon as possible now! -- adrian */
	/* No, 'cause after a restart it would cause all sorts of nick collides */
	/* um.  by waiting even longer, that just means we have even *more*
	 * nick collisions.  what a stupid idea. set an event for the IO loop --fl
	 */
	eventAddIsh("try_connections", try_connections, NULL, STARTUP_CONNECTIONS_TIME);
	eventAddOnce("try_connections_startup", try_connections, NULL, 0);

	eventAddIsh("collect_zipstats", collect_zipstats, NULL, ZIPSTATS_TIME);

	/* Setup the timeout check. I'll shift it later :)  -- adrian */
	eventAddIsh("comm_checktimeouts", comm_checktimeouts, NULL, 1);

	eventAdd("check_rehash", check_rehash, NULL, 1);

	if(ConfigServerHide.links_delay > 0)
		eventAdd("cache_links", cache_links, NULL,
			    ConfigServerHide.links_delay);
	else
		ConfigServerHide.links_disabled = 1;

	if(splitmode)
		eventAdd("check_splitmode", check_splitmode, NULL, 2);

	ServerRunning = 1;

	print_startup(getpid());

	charybdis_io_loop();

	return 0;
}