int openSockfd[MAXSOCKS];
bool nofork = false;
+time_t TIME = time(NULL);
+
namespace nspace
{
#ifdef GCC34
if (bail)
{
printf("There were errors in your configuration:\n%s",errstr.str().c_str());
- exit(0);
+ Exit(0);
}
else
{
strlcpy(chanlist[cname]->name, cname,CHANMAX);
chanlist[cname]->topiclock = 1;
chanlist[cname]->noexternal = 1;
- chanlist[cname]->created = time(NULL);
+ chanlist[cname]->created = TIME;
strcpy(chanlist[cname]->topic, "");
strncpy(chanlist[cname]->setby, user->nick,NICKMAX);
chanlist[cname]->topicset = 0;
signal (SIGSEGV, SIG_IGN);
signal (SIGURG, SIG_IGN);
signal (SIGKILL, SIG_IGN);
- log(DEBUG,"*** fell down a pothole in the road to perfection ***");
+ log(DEFAULT,"*** fell down a pothole in the road to perfection ***");
send_error("Error! Segmentation fault! save meeeeeeeeeeeeee *splat!*");
- exit(status);
+ Exit(status);
}
if (!FileExists(CONFIG_FILE))
{
printf("ERROR: Cannot open config file: %s\nExiting...\n",CONFIG_FILE);
- log(DEBUG,"main: no config");
+ log(DEFAULT,"main: no config");
printf("ERROR: Your config file is missing, this IRCd will self destruct in 10 seconds!\n");
Exit(ERROR);
}
if (InspIRCd() == ERROR)
{
- log(DEBUG,"main: daemon function bailed");
+ log(DEFAULT,"main: daemon function bailed");
printf("ERROR: could not initialise. Shutting down.\n");
Exit(ERROR);
}
for (user_hash::iterator i = whowas.begin(); i != whowas.end(); i++)
{
// 3600 seconds in an hour ;)
- if ((i->second->signon)<(time(NULL)-(WHOWAS_STALE*3600)))
+ if ((i->second->signon)<(TIME-(WHOWAS_STALE*3600)))
{
if (i->second) delete i->second;
i->second = a;
strncpy(clientlist[tempnick]->server, ServerName,256);
strncpy(clientlist[tempnick]->ident, "unknown",9);
clientlist[tempnick]->registered = 0;
- clientlist[tempnick]->signon = time(NULL)+dns_timeout;
- clientlist[tempnick]->nping = time(NULL)+240+dns_timeout;
+ clientlist[tempnick]->signon = TIME+dns_timeout;
+ clientlist[tempnick]->nping = TIME+240+dns_timeout;
clientlist[tempnick]->lastping = 1;
clientlist[tempnick]->port = port;
strncpy(clientlist[tempnick]->ip,ip,32);
// set the registration timeout for this user
unsigned long class_regtimeout = 90;
- for (ClassVector::iterator i = Classes.begin(); i != Classes.end(); i++)
- {
- if (match(clientlist[tempnick]->host,i->host) && (i->type == CC_ALLOW))
- {
- class_regtimeout = (unsigned long)i->registration_timeout;
- break;
- }
- }
-
int class_flood = 0;
+
for (ClassVector::iterator i = Classes.begin(); i != Classes.end(); i++)
{
if (match(clientlist[tempnick]->host,i->host) && (i->type == CC_ALLOW))
{
+ class_regtimeout = (unsigned long)i->registration_timeout;
class_flood = i->flood;
break;
}
}
- clientlist[tempnick]->timeout = time(NULL)+class_regtimeout;
+ clientlist[tempnick]->timeout = TIME+class_regtimeout;
clientlist[tempnick]->flood = class_flood;
for (int i = 0; i < MAXCHANS; i++)
kill_link(clientlist[tempnick],"No more connections allowed in this class");
- char* r = matches_zline(ip);
char* e = matches_exception(ip);
- if ((r) && (!e))
+ if (!e)
{
- char reason[MAXBUF];
- snprintf(reason,MAXBUF,"Z-Lined: %s",r);
- kill_link(clientlist[tempnick],reason);
+ char* r = matches_zline(ip);
+ if (r)
+ {
+ char reason[MAXBUF];
+ snprintf(reason,MAXBUF,"Z-Lined: %s",r);
+ kill_link(clientlist[tempnick],reason);
+ }
}
}
-
+// this function counts all users connected, wether they are registered or NOT.
int usercnt(void)
{
return clientlist.size();
}
+// this counts only registered users, so that the percentages in /MAP don't mess up when users are sitting in an unregistered state
+int registered_usercount(void)
+{
+ int c = 0;
+ for (user_hash::const_iterator i = clientlist.begin(); i != clientlist.end(); i++)
+ {
+ if ((i->second->fd) && (isnick(i->second->nick))) c++;
+ }
+ return c;
+}
int usercount_invisible(void)
{
}
WholeMOTD = WholeMOTD + std::string(":") + std::string(ServerName) + std::string(" 376 ") + std::string(user->nick) + std::string(" :End of message of the day.\r\n");
// only one write operation
- send(user->fd,WholeMOTD.c_str(),WholeMOTD.length(),NULL);
+ send(user->fd,WholeMOTD.c_str(),WholeMOTD.length(),0);
}
void FullConnectUser(userrec* user)
{
user->registered = 7;
- user->idle_lastmsg = time(NULL);
+ user->idle_lastmsg = TIME;
log(DEBUG,"ConnectUser: %s",user->nick);
if (strcmp(Passwd(user),"") && (!user->haspassed))
log(DEBUG,"Processing command");
/* activity resets the ping pending timer */
- user->nping = time(NULL) + 120;
+ user->nping = TIME + 120;
if ((items) < cmdlist[i].min_params)
{
log(DEBUG,"process_command: not enough parameters: %s %s",user->nick,command);
}
-void createcommand(char* cmd, handlerfunc f, char flags, int minparams)
+void createcommand(char* cmd, handlerfunc f, char flags, int minparams,char* source)
{
command_t comm;
/* create the command and push it onto the table */
strlcpy(comm.command,cmd,MAXBUF);
+ strlcpy(comm.source,source,MAXBUF);
comm.handler_function = f;
comm.flags_needed = flags;
comm.min_params = minparams;
log(DEBUG,"Added command %s (%d parameters)",cmd,minparams);
}
+bool removecommands(const char* source)
+{
+ bool go_again = true;
+ while (go_again)
+ {
+ go_again = false;
+ for (std::deque<command_t>::iterator i = cmdlist.begin(); i != cmdlist.end(); i++)
+ {
+ if (!strcmp(i->source,source))
+ {
+ log(DEBUG,"removecommands(%s) Removing dependent command: %s",i->source,i->command);
+ cmdlist.erase(i);
+ go_again = true;
+ break;
+ }
+ }
+ }
+ return true;
+}
+
void SetupCommandTable(void)
{
- createcommand("USER",handle_user,0,4);
- createcommand("NICK",handle_nick,0,1);
- createcommand("QUIT",handle_quit,0,0);
- createcommand("VERSION",handle_version,0,0);
- createcommand("PING",handle_ping,0,1);
- createcommand("PONG",handle_pong,0,1);
- createcommand("ADMIN",handle_admin,0,0);
- createcommand("PRIVMSG",handle_privmsg,0,2);
- createcommand("INFO",handle_info,0,0);
- createcommand("TIME",handle_time,0,0);
- createcommand("WHOIS",handle_whois,0,1);
- createcommand("WALLOPS",handle_wallops,'o',1);
- createcommand("NOTICE",handle_notice,0,2);
- createcommand("JOIN",handle_join,0,1);
- createcommand("NAMES",handle_names,0,1);
- createcommand("PART",handle_part,0,1);
- createcommand("KICK",handle_kick,0,2);
- createcommand("MODE",handle_mode,0,1);
- createcommand("TOPIC",handle_topic,0,1);
- createcommand("WHO",handle_who,0,1);
- createcommand("MOTD",handle_motd,0,0);
- createcommand("RULES",handle_rules,0,0);
- createcommand("OPER",handle_oper,0,2);
- createcommand("LIST",handle_list,0,0);
- createcommand("DIE",handle_die,'o',1);
- createcommand("RESTART",handle_restart,'o',1);
- createcommand("KILL",handle_kill,'o',2);
- createcommand("REHASH",handle_rehash,'o',0);
- createcommand("LUSERS",handle_lusers,0,0);
- createcommand("STATS",handle_stats,0,1);
- createcommand("USERHOST",handle_userhost,0,1);
- createcommand("AWAY",handle_away,0,0);
- createcommand("ISON",handle_ison,0,0);
- createcommand("SUMMON",handle_summon,0,0);
- createcommand("USERS",handle_users,0,0);
- createcommand("INVITE",handle_invite,0,2);
- createcommand("PASS",handle_pass,0,1);
- createcommand("TRACE",handle_trace,'o',0);
- createcommand("WHOWAS",handle_whowas,0,1);
- createcommand("CONNECT",handle_connect,'o',1);
- createcommand("SQUIT",handle_squit,'o',0);
- createcommand("MODULES",handle_modules,'o',0);
- createcommand("LINKS",handle_links,0,0);
- createcommand("MAP",handle_map,0,0);
- createcommand("KLINE",handle_kline,'o',1);
- createcommand("GLINE",handle_gline,'o',1);
- createcommand("ZLINE",handle_zline,'o',1);
- createcommand("QLINE",handle_qline,'o',1);
- createcommand("ELINE",handle_eline,'o',1);
- createcommand("SERVER",handle_server,0,0);
+ createcommand("USER",handle_user,0,4,"<core>");
+ createcommand("NICK",handle_nick,0,1,"<core>");
+ createcommand("QUIT",handle_quit,0,0,"<core>");
+ createcommand("VERSION",handle_version,0,0,"<core>");
+ createcommand("PING",handle_ping,0,1,"<core>");
+ createcommand("PONG",handle_pong,0,1,"<core>");
+ createcommand("ADMIN",handle_admin,0,0,"<core>");
+ createcommand("PRIVMSG",handle_privmsg,0,2,"<core>");
+ createcommand("INFO",handle_info,0,0,"<core>");
+ createcommand("TIME",handle_time,0,0,"<core>");
+ createcommand("WHOIS",handle_whois,0,1,"<core>");
+ createcommand("WALLOPS",handle_wallops,'o',1,"<core>");
+ createcommand("NOTICE",handle_notice,0,2,"<core>");
+ createcommand("JOIN",handle_join,0,1,"<core>");
+ createcommand("NAMES",handle_names,0,1,"<core>");
+ createcommand("PART",handle_part,0,1,"<core>");
+ createcommand("KICK",handle_kick,0,2,"<core>");
+ createcommand("MODE",handle_mode,0,1,"<core>");
+ createcommand("TOPIC",handle_topic,0,1,"<core>");
+ createcommand("WHO",handle_who,0,1,"<core>");
+ createcommand("MOTD",handle_motd,0,0,"<core>");
+ createcommand("RULES",handle_rules,0,0,"<core>");
+ createcommand("OPER",handle_oper,0,2,"<core>");
+ createcommand("LIST",handle_list,0,0,"<core>");
+ createcommand("DIE",handle_die,'o',1,"<core>");
+ createcommand("RESTART",handle_restart,'o',1,"<core>");
+ createcommand("KILL",handle_kill,'o',2,"<core>");
+ createcommand("REHASH",handle_rehash,'o',0,"<core>");
+ createcommand("LUSERS",handle_lusers,0,0,"<core>");
+ createcommand("STATS",handle_stats,0,1,"<core>");
+ createcommand("USERHOST",handle_userhost,0,1,"<core>");
+ createcommand("AWAY",handle_away,0,0,"<core>");
+ createcommand("ISON",handle_ison,0,0,"<core>");
+ createcommand("SUMMON",handle_summon,0,0,"<core>");
+ createcommand("USERS",handle_users,0,0,"<core>");
+ createcommand("INVITE",handle_invite,0,2,"<core>");
+ createcommand("PASS",handle_pass,0,1,"<core>");
+ createcommand("TRACE",handle_trace,'o',0,"<core>");
+ createcommand("WHOWAS",handle_whowas,0,1,"<core>");
+ createcommand("CONNECT",handle_connect,'o',1,"<core>");
+ createcommand("SQUIT",handle_squit,'o',0,"<core>");
+ createcommand("MODULES",handle_modules,'o',0,"<core>");
+ createcommand("LINKS",handle_links,0,0,"<core>");
+ createcommand("MAP",handle_map,0,0,"<core>");
+ createcommand("KLINE",handle_kline,'o',1,"<core>");
+ createcommand("GLINE",handle_gline,'o',1,"<core>");
+ createcommand("ZLINE",handle_zline,'o',1,"<core>");
+ createcommand("QLINE",handle_qline,'o',1,"<core>");
+ createcommand("ELINE",handle_eline,'o',1,"<core>");
+ createcommand("LOADMODULE",handle_loadmodule,'o',1,"<core>");
+ createcommand("UNLOADMODULE",handle_unloadmodule,'o',1,"<core>");
+ createcommand("SERVER",handle_server,0,0,"<core>");
}
void process_buffer(const char* cmdbuf,userrec *user)
// send start of sync marker: Y <timestamp>
// at this point the ircd receiving it starts broadcasting this netburst to all ircds
// except the ones its receiving it from.
- snprintf(data,MAXBUF,"Y %d",time(NULL));
+ snprintf(data,MAXBUF,"Y %d",TIME);
serv->SendPacket(data,tcp_host);
// send users and channels
for (user_hash::iterator u = clientlist.begin(); u != clientlist.end(); u++)
}
}
- snprintf(data,MAXBUF,"F %d",time(NULL));
+ snprintf(data,MAXBUF,"F %d",TIME);
serv->SendPacket(data,tcp_host);
log(DEBUG,"Sent sync");
// ircd sends its serverlist after the end of sync here
int reap_counter = 0;
+char MODERR[MAXBUF];
+
+char* ModuleError()
+{
+ return MODERR;
+}
+
+bool UnloadModule(const char* filename)
+{
+ for (int j = 0; j != module_names.size(); j++)
+ {
+ if (module_names[j] == std::string(filename))
+ {
+ // found the module
+ log(DEBUG,"Deleting module...");
+ delete factory[j]->factory;
+ log(DEBUG,"Deleting module factory...");
+ delete factory[j];
+ log(DEBUG,"Erasing module entry...");
+ factory[j] = NULL;
+ // here we should locate ALL resources claimed by this module... and release them
+ // for example commands
+ log(DEBUG,"Erasing module vector...");
+ for (std::vector<ircd_module*>::iterator t = factory.begin(); t != factory.end(); t++)
+ {
+ if (*t == NULL)
+ {
+ factory.erase(t);
+ break;
+ }
+ }
+ log(DEBUG,"Erasing module name vector...");
+ for (std::vector<std::string>::iterator v = module_names.begin(); v != module_names.end(); v++)
+ {
+ if (*v == std::string(filename))
+ {
+ module_names.erase(v);
+ break;
+ }
+ }
+ log(DEBUG,"Removing dependent commands...");
+ removecommands(filename);
+ log(DEFAULT,"Module %s unloaded",filename);
+ MODCOUNT--;
+ return true;
+ }
+ }
+ log(DEFAULT,"Module %s is not loaded, cannot unload it!",filename);
+ snprintf(MODERR,MAXBUF,"Module not loaded");
+ return false;
+}
+
+bool LoadModule(const char* filename)
+{
+ char modfile[MAXBUF];
+ snprintf(modfile,MAXBUF,"%s/%s",MOD_PATH,filename,&config_f);
+ log(DEBUG,"Loading module: %s",modfile);
+ if (FileExists(modfile))
+ {
+ for (int j = 0; j < module_names.size(); j++)
+ {
+ if (module_names[j] == std::string(filename))
+ {
+ log(DEFAULT,"Module %s is already loaded, cannot load a module twice!",modfile);
+ snprintf(MODERR,MAXBUF,"Module already loaded");
+ return false;
+ }
+ }
+ factory[MODCOUNT+1] = new ircd_module(modfile);
+ if (factory[MODCOUNT+1]->LastError())
+ {
+ log(DEFAULT,"Unable to load %s: %s",modfile,factory[MODCOUNT+1]->LastError());
+ snprintf(MODERR,MAXBUF,"Loader/Linker error: %s",factory[MODCOUNT+1]->LastError());
+ MODCOUNT--;
+ return false;
+ }
+ if (factory[MODCOUNT+1]->factory)
+ {
+ modules[MODCOUNT+1] = factory[MODCOUNT+1]->factory->CreateModule();
+ /* save the module and the module's classfactory, if
+ * this isnt done, random crashes can occur :/ */
+ module_names.push_back(filename);
+ }
+ else
+ {
+ log(DEFAULT,"Unable to load %s",modfile);
+ snprintf(MODERR,MAXBUF,"Factory function failed!");
+ return false;
+ }
+ }
+ else
+ {
+ log(DEFAULT,"InspIRCd: startup: Module Not Found %s",modfile);
+ snprintf(MODERR,MAXBUF,"Module file could not be found");
+ return false;
+ }
+ MODCOUNT++;
+ return true;
+}
int InspIRCd(void)
{
{
printf("WARNING!!! You are running an irc server as ROOT!!! DO NOT DO THIS!!!\n\n");
Exit(ERROR);
- log(DEBUG,"InspIRCd: startup: not starting with UID 0!");
+ log(DEFAULT,"InspIRCd: startup: not starting with UID 0!");
}
SetupCommandTable();
log(DEBUG,"InspIRCd: startup: default command table set up");
printf("\n");
/* BugFix By Craig! :p */
- count = 0;
+ MODCOUNT = -1;
for (count2 = 0; count2 < ConfValueEnum("module",&config_f); count2++)
{
- char modfile[MAXBUF];
ConfValue("module","name",count2,configToken,&config_f);
- snprintf(modfile,MAXBUF,"%s/%s",MOD_PATH,configToken,&config_f);
- printf("Loading module... \033[1;37m%s\033[0;37m\n",modfile);
- log(DEBUG,"InspIRCd: startup: Loading module: %s",modfile);
- /* If The File Doesnt exist, Trying to load it
- * Will Segfault the IRCd.. So, check to see if
- * it Exists, Before Proceeding. */
- if (FileExists(modfile))
+ printf("Loading module... \033[1;37m%s\033[0;37m\n",configToken);
+ if (!LoadModule(configToken))
{
- factory[count] = new ircd_module(modfile);
- if (factory[count]->LastError())
- {
- log(DEBUG,"Unable to load %s: %s",modfile,factory[count]->LastError());
- printf("Unable to load %s: %s\nExiting...\n",modfile,factory[count]->LastError());
- Exit(ERROR);
- }
- if (factory[count]->factory)
- {
- modules[count] = factory[count]->factory->CreateModule();
- /* save the module and the module's classfactory, if
- * this isnt done, random crashes can occur :/ */
- module_names.push_back(modfile);
- }
- else
- {
- log(DEBUG,"Unable to load %s",modfile);
- printf("Unable to load %s\nExiting...\n",modfile);
- Exit(ERROR);
- }
- /* Increase the Count */
- count++;
- }
- else
- {
- log(DEBUG,"InspIRCd: startup: Module Not Found %s",modfile);
- printf("Module Not Found: \033[1;37m%s\033[0;37m, Skipping\n",modfile);
+ log(DEBUG,"Exiting due to a module loader error.");
+ printf("There was an error loading a module: %s\n",ModuleError());
+ Exit(0);
}
}
- MODCOUNT = count - 1;
log(DEBUG,"Total loaded modules: %d",MODCOUNT+1);
printf("\nInspIRCd is now running!\n");
{
if (DaemonSeed() == ERROR)
{
- log(DEBUG,"InspIRCd: startup: can't daemonise");
+ log(DEFAULT,"InspIRCd: startup: can't daemonise");
printf("ERROR: could not go into daemon mode. Shutting down.\n");
Exit(ERROR);
}
}
if (BindSocket(openSockfd[boundPortCount],client,server,ports[count],addrs[count]) == ERROR)
{
- log(DEBUG,"InspIRCd: startup: failed to bind port %d",ports[count]);
+ log(DEFAULT,"InspIRCd: startup: failed to bind port %d",ports[count]);
}
else /* well we at least bound to one socket so we'll continue */
{
/* if we didn't bind to anything then abort */
if (boundPortCount == 0)
{
- log(DEBUG,"InspIRCd: startup: no ports bound, bailing!");
+ log(DEFAULT,"InspIRCd: startup: no ports bound, bailing!");
return (ERROR);
}
fd_set serverfds;
timeval tvs;
- tvs.tv_usec = 10000L;
+ tvs.tv_usec = 7000L;
tvs.tv_sec = 0;
tv.tv_sec = 0;
- tv.tv_usec = 10000L;
+ tv.tv_usec = 7000L;
char data[10240];
timeval tval;
fd_set sfd;
- tval.tv_usec = 10000L;
+ tval.tv_usec = 7000L;
tval.tv_sec = 0;
int total_in_this_set = 0;
int v = 0;
+ bool expire_run = false;
/* main loop, this never returns */
for (;;)
#endif
// poll dns queue
dns_poll();
-
FD_ZERO(&sfd);
+ // we only read time() once per iteration rather than tons of times!
+ TIME = time(NULL);
+
user_hash::iterator count2 = clientlist.begin();
// *FIX* Instead of closing sockets in kill_link when they receive the ERROR :blah line, we should queue
// them in a list, then reap the list every second or so.
- if ((reap_counter % 50) == 0)
+ if (((TIME % 5) == 0) && (!expire_run))
{
- // These functions eat cpu, and should not be done so often!
-
- // update the status of klines, etc
- expire_lines();
-#ifdef _POSIX_PRIORITY_SCHEDULING
- sched_yield();
-#endif
+ expire_lines();
+ expire_run = true;
}
+ if ((TIME % 5) == 1)
+ expire_run = false;
if (reap_counter>300)
{
if (fd_reap.size() > 0)
// serverFds timevals went here
- tvs.tv_usec = 10000L;
+ tvs.tv_usec = 7000L;
int servresult = select(32767, &serverfds, NULL, NULL, &tvs);
if (servresult > 0)
{
char remotehost[MAXBUF],resolved[MAXBUF];
length = sizeof (client);
incomingSockfd = accept (me[x]->fd, (sockaddr *) &client, &length);
- strlcpy(remotehost,(char *)inet_ntoa(client.sin_addr),MAXBUF);
- if(CleanAndResolve(resolved, remotehost) != TRUE)
+ if (incomingSockfd != -1)
{
- strlcpy(resolved,remotehost,MAXBUF);
+ strlcpy(remotehost,(char *)inet_ntoa(client.sin_addr),MAXBUF);
+ if(CleanAndResolve(resolved, remotehost) != TRUE)
+ {
+ strlcpy(resolved,remotehost,MAXBUF);
+ }
+ // add to this connections ircd_connector vector
+ // *FIX* - we need the LOCAL port not the remote port in &client!
+ me[x]->AddIncoming(incomingSockfd,resolved,me[x]->port);
}
- // add to this connections ircd_connector vector
- // *FIX* - we need the LOCAL port not the remote port in &client!
- me[x]->AddIncoming(incomingSockfd,resolved,me[x]->port);
}
}
}
// registration timeout -- didnt send USER/NICK/HOST in the time specified in
// their connection class.
- if ((time(NULL) > count2->second->timeout) && (count2->second->registered != 7))
+ if ((TIME > count2->second->timeout) && (count2->second->registered != 7))
{
log(DEBUG,"InspIRCd: registration timeout: %s",count2->second->nick);
kill_link(count2->second,"Registration timeout");
goto label;
}
- if ((time(NULL) > count2->second->signon) && (count2->second->registered == 3))
+ if ((TIME > count2->second->signon) && (count2->second->registered == 3))
{
count2->second->dns_done = true;
FullConnectUser(count2->second);
FullConnectUser(count2->second);
goto label;
}
- if (((time(NULL)) > count2->second->nping) && (isnick(count2->second->nick)) && (count2->second->registered == 7))
+ if ((TIME > count2->second->nping) && (isnick(count2->second->nick)) && (count2->second->registered == 7))
{
if ((!count2->second->lastping) && (count2->second->registered == 7))
{
Write(count2->second->fd,"PING :%s",ServerName);
log(DEBUG,"InspIRCd: pinging: %s",count2->second->nick);
count2->second->lastping = 0;
- count2->second->nping = time(NULL)+120;
+ count2->second->nping = TIME+120;
}
}
count2++;
// tvals defined here
- tval.tv_usec = 10000L;
+ tval.tv_usec = 7000L;
selectResult2 = select(65535, &sfd, NULL, NULL, &tval);
// now loop through all of the items in this pool if any are waiting
FD_SET (openSockfd[count], &selectFds);
}
- tv.tv_usec = 10000L;
+ tv.tv_usec = 7000L;
selectResult = select(MAXSOCKS, &selectFds, NULL, NULL, &tv);
/* select is reporting a waiting socket. Poll them all to find out which */