+/*
+ * InspIRCd -- Internet Relay Chat Daemon
+ *
+ * Copyright (C) 2009 Daniel De Graaf <danieldg@inspircd.org>
+ * Copyright (C) 2005-2008 Craig Edwards <craigedwards@brainbox.cc>
+ * Copyright (C) 2006-2008 Robin Burchell <robin+git@viroteck.net>
+ * Copyright (C) 2007 Dennis Friis <peavey@inspircd.org>
+ *
+ * This file is part of InspIRCd. InspIRCd 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, version 2.
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ */
+
+
+#include "inspircd.h"
+
+/* $ModDesc: Provides support for the /WATCH command */
+
+
+/*
+ * Okay, it's nice that this was documented and all, but I at least understood very little
+ * of it, so I'm going to attempt to explain the data structures in here a bit more.
+ *
+ * For efficiency, many data structures are kept.
+ *
+ * The first is a global list `watchentries':
+ * hash_map<irc::string, std::deque<User*> >
+ *
+ * That is, if nick 'w00t' is being watched by user pointer 'Brain' and 'Om', <w00t, (Brain, Om)>
+ * will be in the watchentries list.
+ *
+ * The second is that each user has a per-user data structure attached to their user record via Extensible:
+ * std::map<irc::string, std::string> watchlist;
+ * So, in the above example with w00t watched by Brain and Om, we'd have:
+ * Brain-
+ * `- w00t
+ * Om-
+ * `- w00t
+ *
+ * Hopefully this helps any brave soul that ventures into this file other than me. :-)
+ * -- w00t (mar 30, 2008)
+ */
+
+
+/* This module has been refactored to provide a very efficient (in terms of cpu time)
+ * implementation of /WATCH.
+ *
+ * To improve the efficiency of watch, many lists are kept. The first primary list is
+ * a hash_map of who's being watched by who. For example:
+ *
+ * KEY: Brain ---> Watched by: Boo, w00t, Om
+ * KEY: Boo ---> Watched by: Brain, w00t
+ *
+ * This is used when we want to tell all the users that are watching someone that
+ * they are now available or no longer available. For example, if the hash was
+ * populated as shown above, then when Brain signs on, messages are sent to Boo, w00t
+ * and Om by reading their 'watched by' list. When this occurs, their online status
+ * in each of these users lists (see below) is also updated.
+ *
+ * Each user also has a seperate (smaller) map attached to their User whilst they
+ * have any watch entries, which is managed by class Extensible. When they add or remove
+ * a watch entry from their list, it is inserted here, as well as the main list being
+ * maintained. This map also contains the user's online status. For users that are
+ * offline, the key points at an empty string, and for users that are online, the key
+ * points at a string containing "users-ident users-host users-signon-time". This is
+ * stored in this manner so that we don't have to FindUser() to fetch this info, the
+ * users signon can populate the field for us.
+ *
+ * For example, going again on the example above, this would be w00t's watchlist:
+ *
+ * KEY: Boo ---> Status: "Boo brains.sexy.babe 535342348"
+ * KEY: Brain ---> Status: ""
+ *
+ * In this list we can see that Boo is online, and Brain is offline. We can then
+ * use this list for 'WATCH L', and 'WATCH S' can be implemented as a combination
+ * of the above two data structures, with minimum CPU penalty for doing so.
+ *
+ * In short, the least efficient this ever gets is O(n), and thats only because
+ * there are parts that *must* loop (e.g. telling all users that are watching a
+ * nick that the user online), however this is a *major* improvement over the
+ * 1.0 implementation, which in places had O(n^n) and worse in it, because this
+ * implementation scales based upon the sizes of the watch entries, whereas the
+ * old system would scale (or not as the case may be) according to the total number
+ * of users using WATCH.
+ */
+
+/*
+ * Before you start screaming, this definition is only used here, so moving it to a header is pointless.
+ * Yes, it's horrid. Blame cl for being different. -- w00t
+ */
+
+typedef nspace::hash_map<irc::string, std::deque<User*>, irc::hash> watchentries;
+typedef std::map<irc::string, std::string> watchlist;
+
+/* Who's watching each nickname.
+ * NOTE: We do NOT iterate this to display a user's WATCH list!
+ * See the comments above!
+ */
+watchentries* whos_watching_me;
+
+class CommandSVSWatch : public Command
+{
+ public:
+ CommandSVSWatch(Module* Creator) : Command(Creator,"SVSWATCH", 2)
+ {
+ syntax = "<target> [C|L|S]|[+|-<nick>]";
+ TRANSLATE3(TR_NICK, TR_TEXT, TR_END); /* we watch for a nick. not a UID. */
+ }
+
+ CmdResult Handle (const std::vector<std::string> ¶meters, User *user)
+ {
+ if (!ServerInstance->ULine(user->server))
+ return CMD_FAILURE;
+
+ User *u = ServerInstance->FindNick(parameters[0]);
+ if (!u)
+ return CMD_FAILURE;
+
+ if (IS_LOCAL(u))
+ {
+ ServerInstance->Parser->CallHandler("WATCH", parameters, u);
+ }
+
+ return CMD_SUCCESS;
+ }
+
+ RouteDescriptor GetRouting(User* user, const std::vector<std::string>& parameters)
+ {
+ User* target = ServerInstance->FindNick(parameters[0]);
+ if (target)
+ return ROUTE_OPT_UCAST(target->server);
+ return ROUTE_LOCALONLY;
+ }
+};
+
+/** Handle /WATCH
+ */
+class CommandWatch : public Command
+{
+ unsigned int& MAX_WATCH;
+ public:
+ SimpleExtItem<watchlist> ext;
+ CmdResult remove_watch(User* user, const char* nick)
+ {
+ // removing an item from the list
+ if (!ServerInstance->IsNick(nick, ServerInstance->Config->Limits.NickMax))
+ {
+ user->WriteNumeric(942, "%s %s :Invalid nickname", user->nick.c_str(), nick);
+ return CMD_FAILURE;
+ }
+
+ watchlist* wl = ext.get(user);
+ if (wl)
+ {
+ /* Yup, is on my list */
+ watchlist::iterator n = wl->find(nick);
+
+ if (n != wl->end())
+ {
+ if (!n->second.empty())
+ user->WriteNumeric(602, "%s %s %s :stopped watching", user->nick.c_str(), n->first.c_str(), n->second.c_str());
+ else
+ user->WriteNumeric(602, "%s %s * * 0 :stopped watching", user->nick.c_str(), nick);
+
+ wl->erase(n);
+ }
+
+ if (wl->empty())
+ {
+ ext.unset(user);
+ }
+
+ watchentries::iterator x = whos_watching_me->find(nick);
+ if (x != whos_watching_me->end())
+ {
+ /* People are watching this user, am i one of them? */
+ std::deque<User*>::iterator n2 = std::find(x->second.begin(), x->second.end(), user);
+ if (n2 != x->second.end())
+ /* I'm no longer watching you... */
+ x->second.erase(n2);
+
+ if (x->second.empty())
+ /* nobody else is, either. */
+ whos_watching_me->erase(nick);
+ }
+ }
+
+ return CMD_SUCCESS;
+ }
+
+ CmdResult add_watch(User* user, const char* nick)
+ {
+ if (!ServerInstance->IsNick(nick, ServerInstance->Config->Limits.NickMax))
+ {
+ user->WriteNumeric(942, "%s %s :Invalid nickname",user->nick.c_str(),nick);
+ return CMD_FAILURE;
+ }
+
+ watchlist* wl = ext.get(user);
+ if (!wl)
+ {
+ wl = new watchlist();
+ ext.set(user, wl);
+ }
+
+ if (wl->size() >= MAX_WATCH)
+ {
+ user->WriteNumeric(512, "%s %s :Too many WATCH entries", user->nick.c_str(), nick);
+ return CMD_FAILURE;
+ }
+
+ watchlist::iterator n = wl->find(nick);
+ if (n == wl->end())
+ {
+ /* Don't already have the user on my watch list, proceed */
+ watchentries::iterator x = whos_watching_me->find(nick);
+ if (x != whos_watching_me->end())
+ {
+ /* People are watching this user, add myself */
+ x->second.push_back(user);
+ }
+ else
+ {
+ std::deque<User*> newlist;
+ newlist.push_back(user);
+ (*(whos_watching_me))[nick] = newlist;
+ }
+
+ User* target = ServerInstance->FindNick(nick);
+ if ((target) && (target->registered == REG_ALL))
+ {
+ (*wl)[nick] = std::string(target->ident).append(" ").append(target->dhost).append(" ").append(ConvToStr(target->age));
+ user->WriteNumeric(604, "%s %s %s :is online",user->nick.c_str(), nick, (*wl)[nick].c_str());
+ if (IS_AWAY(target))
+ {
+ user->WriteNumeric(609, "%s %s %s %s %lu :is away", user->nick.c_str(), target->nick.c_str(), target->ident.c_str(), target->dhost.c_str(), (unsigned long) target->awaytime);
+ }
+ }
+ else
+ {
+ (*wl)[nick].clear();
+ user->WriteNumeric(605, "%s %s * * 0 :is offline",user->nick.c_str(), nick);
+ }
+ }
+
+ return CMD_SUCCESS;
+ }
+
+ CommandWatch(Module* parent, unsigned int &maxwatch) : Command(parent,"WATCH", 0), MAX_WATCH(maxwatch), ext("watchlist", parent)
+ {
+ syntax = "[C|L|S]|[+|-<nick>]";
+ TRANSLATE2(TR_TEXT, TR_END); /* we watch for a nick. not a UID. */
+ }
+
+ CmdResult Handle (const std::vector<std::string> ¶meters, User *user)
+ {
+ if (parameters.empty())
+ {
+ watchlist* wl = ext.get(user);
+ if (wl)
+ {
+ for (watchlist::iterator q = wl->begin(); q != wl->end(); q++)
+ {
+ if (!q->second.empty())
+ user->WriteNumeric(604, "%s %s %s :is online", user->nick.c_str(), q->first.c_str(), q->second.c_str());
+ }
+ }
+ user->WriteNumeric(607, "%s :End of WATCH list",user->nick.c_str());
+ }
+ else if (parameters.size() > 0)
+ {
+ for (int x = 0; x < (int)parameters.size(); x++)
+ {
+ const char *nick = parameters[x].c_str();
+ if (!strcasecmp(nick,"C"))
+ {
+ // watch clear
+ watchlist* wl = ext.get(user);
+ if (wl)
+ {
+ for (watchlist::iterator i = wl->begin(); i != wl->end(); i++)
+ {
+ watchentries::iterator i2 = whos_watching_me->find(i->first);
+ if (i2 != whos_watching_me->end())
+ {
+ /* People are watching this user, am i one of them? */
+ std::deque<User*>::iterator n = std::find(i2->second.begin(), i2->second.end(), user);
+ if (n != i2->second.end())
+ /* I'm no longer watching you... */
+ i2->second.erase(n);
+
+ if (i2->second.empty())
+ /* nobody else is, either. */
+ whos_watching_me->erase(i2);
+ }
+ }
+
+ ext.unset(user);
+ }
+ }
+ else if (!strcasecmp(nick,"L"))
+ {
+ watchlist* wl = ext.get(user);
+ if (wl)
+ {
+ for (watchlist::iterator q = wl->begin(); q != wl->end(); q++)
+ {
+ User* targ = ServerInstance->FindNick(q->first.c_str());
+ if (targ && !q->second.empty())
+ {
+ user->WriteNumeric(604, "%s %s %s :is online", user->nick.c_str(), q->first.c_str(), q->second.c_str());
+ if (IS_AWAY(targ))
+ {
+ user->WriteNumeric(609, "%s %s %s %s %lu :is away", user->nick.c_str(), targ->nick.c_str(), targ->ident.c_str(), targ->dhost.c_str(), (unsigned long) targ->awaytime);
+ }
+ }
+ else
+ user->WriteNumeric(605, "%s %s * * 0 :is offline", user->nick.c_str(), q->first.c_str());
+ }
+ }
+ user->WriteNumeric(607, "%s :End of WATCH list",user->nick.c_str());
+ }
+ else if (!strcasecmp(nick,"S"))
+ {
+ watchlist* wl = ext.get(user);
+ int you_have = 0;
+ int youre_on = 0;
+ std::string list;
+
+ if (wl)
+ {
+ for (watchlist::iterator q = wl->begin(); q != wl->end(); q++)
+ list.append(q->first.c_str()).append(" ");
+ you_have = wl->size();
+ }
+
+ watchentries::iterator i2 = whos_watching_me->find(user->nick.c_str());
+ if (i2 != whos_watching_me->end())
+ youre_on = i2->second.size();
+
+ user->WriteNumeric(603, "%s :You have %d and are on %d WATCH entries", user->nick.c_str(), you_have, youre_on);
+ user->WriteNumeric(606, "%s :%s",user->nick.c_str(), list.c_str());
+ user->WriteNumeric(607, "%s :End of WATCH S",user->nick.c_str());
+ }
+ else if (nick[0] == '-')
+ {
+ nick++;
+ remove_watch(user, nick);
+ }
+ else if (nick[0] == '+')
+ {
+ nick++;
+ add_watch(user, nick);
+ }
+ }
+ }
+ return CMD_SUCCESS;
+ }
+};
+
+class Modulewatch : public Module
+{
+ unsigned int maxwatch;
+ CommandWatch cmdw;
+ CommandSVSWatch sw;
+
+ public:
+ Modulewatch()
+ : maxwatch(32), cmdw(this, maxwatch), sw(this)
+ {
+ whos_watching_me = new watchentries();
+ }
+
+ void init()
+ {
+ OnRehash(NULL);
+ ServerInstance->Modules->AddService(cmdw);
+ ServerInstance->Modules->AddService(sw);
+ ServerInstance->Modules->AddService(cmdw.ext);
+ Implementation eventlist[] = { I_OnRehash, I_OnGarbageCollect, I_OnUserQuit, I_OnPostConnect, I_OnUserPostNick, I_On005Numeric, I_OnSetAway };
+ ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
+ }
+
+ virtual void OnRehash(User* user)
+ {
+ maxwatch = ServerInstance->Config->ConfValue("watch")->getInt("maxentries", 32);
+ if (!maxwatch)
+ maxwatch = 32;
+ }
+
+ virtual ModResult OnSetAway(User *user, const std::string &awaymsg)
+ {
+ std::string numeric;
+ int inum;
+
+ if (awaymsg.empty())
+ {
+ numeric = user->nick + " " + user->ident + " " + user->dhost + " " + ConvToStr(ServerInstance->Time()) + " :is no longer away";
+ inum = 599;
+ }
+ else
+ {
+ numeric = user->nick + " " + user->ident + " " + user->dhost + " " + ConvToStr(ServerInstance->Time()) + " :" + awaymsg;
+ inum = 598;
+ }
+
+ watchentries::iterator x = whos_watching_me->find(user->nick.c_str());
+ if (x != whos_watching_me->end())
+ {
+ for (std::deque<User*>::iterator n = x->second.begin(); n != x->second.end(); n++)
+ {
+ (*n)->WriteNumeric(inum, (*n)->nick + " " + numeric);
+ }
+ }
+
+ return MOD_RES_PASSTHRU;
+ }
+
+ virtual void OnUserQuit(User* user, const std::string &reason, const std::string &oper_message)
+ {
+ watchentries::iterator x = whos_watching_me->find(user->nick.c_str());
+ if (x != whos_watching_me->end())
+ {
+ for (std::deque<User*>::iterator n = x->second.begin(); n != x->second.end(); n++)
+ {
+ (*n)->WriteNumeric(601, "%s %s %s %s %lu :went offline", (*n)->nick.c_str() ,user->nick.c_str(), user->ident.c_str(), user->dhost.c_str(), (unsigned long) ServerInstance->Time());
+
+ watchlist* wl = cmdw.ext.get(*n);
+ if (wl)
+ /* We were on somebody's notify list, set ourselves offline */
+ (*wl)[user->nick.c_str()].clear();
+ }
+ }
+
+ /* Now im quitting, if i have a notify list, im no longer watching anyone */
+ watchlist* wl = cmdw.ext.get(user);
+ if (wl)
+ {
+ /* Iterate every user on my watch list, and take me out of the whos_watching_me map for each one we're watching */
+ for (watchlist::iterator i = wl->begin(); i != wl->end(); i++)
+ {
+ watchentries::iterator i2 = whos_watching_me->find(i->first);
+ if (i2 != whos_watching_me->end())
+ {
+ /* People are watching this user, am i one of them? */
+ std::deque<User*>::iterator n = std::find(i2->second.begin(), i2->second.end(), user);
+ if (n != i2->second.end())
+ /* I'm no longer watching you... */
+ i2->second.erase(n);
+
+ if (i2->second.empty())
+ /* and nobody else is, either. */
+ whos_watching_me->erase(i2);
+ }
+ }
+ }
+ }
+
+ virtual void OnGarbageCollect()
+ {
+ watchentries* old_watch = whos_watching_me;
+ whos_watching_me = new watchentries();
+
+ for (watchentries::const_iterator n = old_watch->begin(); n != old_watch->end(); n++)
+ whos_watching_me->insert(*n);
+
+ delete old_watch;
+ }
+
+ virtual void OnPostConnect(User* user)
+ {
+ watchentries::iterator x = whos_watching_me->find(user->nick.c_str());
+ if (x != whos_watching_me->end())
+ {
+ for (std::deque<User*>::iterator n = x->second.begin(); n != x->second.end(); n++)
+ {
+ (*n)->WriteNumeric(600, "%s %s %s %s %lu :arrived online", (*n)->nick.c_str(), user->nick.c_str(), user->ident.c_str(), user->dhost.c_str(), (unsigned long) user->age);
+
+ watchlist* wl = cmdw.ext.get(*n);
+ if (wl)
+ /* We were on somebody's notify list, set ourselves online */
+ (*wl)[user->nick.c_str()] = std::string(user->ident).append(" ").append(user->dhost).append(" ").append(ConvToStr(user->age));
+ }
+ }
+ }
+
+ virtual void OnUserPostNick(User* user, const std::string &oldnick)
+ {
+ watchentries::iterator new_offline = whos_watching_me->find(oldnick.c_str());
+ watchentries::iterator new_online = whos_watching_me->find(user->nick.c_str());
+
+ if (new_offline != whos_watching_me->end())
+ {
+ for (std::deque<User*>::iterator n = new_offline->second.begin(); n != new_offline->second.end(); n++)
+ {
+ watchlist* wl = cmdw.ext.get(*n);
+ if (wl)
+ {
+ (*n)->WriteNumeric(601, "%s %s %s %s %lu :went offline", (*n)->nick.c_str(), oldnick.c_str(), user->ident.c_str(), user->dhost.c_str(), (unsigned long) user->age);
+ (*wl)[oldnick.c_str()].clear();
+ }
+ }
+ }
+
+ if (new_online != whos_watching_me->end())
+ {
+ for (std::deque<User*>::iterator n = new_online->second.begin(); n != new_online->second.end(); n++)
+ {
+ watchlist* wl = cmdw.ext.get(*n);
+ if (wl)
+ {
+ (*wl)[user->nick.c_str()] = std::string(user->ident).append(" ").append(user->dhost).append(" ").append(ConvToStr(user->age));
+ (*n)->WriteNumeric(600, "%s %s %s :arrived online", (*n)->nick.c_str(), user->nick.c_str(), (*wl)[user->nick.c_str()].c_str());
+ }
+ }
+ }
+ }
+
+ virtual void On005Numeric(std::string &output)
+ {
+ // we don't really have a limit...
+ output = output + " WATCH=" + ConvToStr(maxwatch);
+ }
+
+ virtual ~Modulewatch()
+ {
+ delete whos_watching_me;
+ }
+
+ virtual Version GetVersion()
+ {
+ return Version("Provides support for the /WATCH command", VF_OPTCOMMON | VF_VENDOR);
+ }
+};
+
+MODULE_INIT(Modulewatch)
+