Shuffle the modules about a bit.

1 files changed, 444 insertions, 0 deletions

diff --git a/modules/monitor.cpp b/modules/monitor.cpp
new file mode 100644
index 000000000..62ffc332d
--- /dev/null
+++ b/modules/monitor.cpp
@@ -0,0 +1,444 @@
+/*
+ * InspIRCd -- Internet Relay Chat Daemon
+ *
+ *   Copyright (C) 2022 delthas
+ *   Copyright (C) 2021 Dominic Hamon
+ *   Copyright (C) 2018-2023 Sadie Powell <sadie@witchery.services>
+ *   Copyright (C) 2016 Attila Molnar <attilamolnar@hush.com>
+ *
+ * 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"
+#include "modules/cap.h"
+#include "modules/isupport.h"
+#include "modules/monitor.h"
+#include "numericbuilder.h"
+
+namespace IRCv3::Monitor
+{
+	class ExtItem;
+	struct Entry;
+	class Manager;
+	class ManagerInternal;
+
+	typedef std::vector<Entry*> WatchedList;
+	typedef std::vector<LocalUser*> WatcherList;
+}
+
+struct IRCv3::Monitor::Entry final
+{
+	WatcherList watchers;
+	std::string nick;
+
+	void SetNick(const std::string& Nick)
+	{
+		nick.clear();
+		// We may show this string to other users so do not leak the casing
+		std::transform(Nick.begin(), Nick.end(), std::back_inserter(nick), ::tolower);
+	}
+
+	const std::string& GetNick() const { return nick; }
+};
+
+class IRCv3::Monitor::Manager final
+{
+	struct ExtData final
+	{
+		WatchedList list;
+	};
+
+	class ExtItem final
+		: public ExtensionItem
+	{
+		Manager& manager;
+
+	public:
+		ExtItem(Module* mod, const std::string& extname, Manager& managerref)
+			: ExtensionItem(mod, extname, ExtensionType::USER)
+			, manager(managerref)
+		{
+		}
+
+		ExtData* Get(User* user, bool create = false)
+		{
+			ExtData* extdata = static_cast<ExtData*>(GetRaw(user));
+			if ((!extdata) && (create))
+			{
+				extdata = new ExtData;
+				SetRaw(user, extdata);
+			}
+			return extdata;
+		}
+
+		void Unset(User* user)
+		{
+			Delete(user, UnsetRaw(user));
+		}
+
+		std::string ToInternal(const Extensible* container, void* item) const noexcept override
+		{
+			std::string ret;
+			const ExtData* extdata = static_cast<ExtData*>(item);
+			for (const auto* entry : extdata->list)
+				ret.append(entry->GetNick()).push_back(' ');
+			if (!ret.empty())
+				ret.pop_back();
+			return ret;
+		}
+
+		void FromInternal(Extensible* container, const std::string& value) noexcept override;
+
+		void Delete(Extensible* container, void* item) override
+		{
+			delete static_cast<ExtData*>(item);
+		}
+	};
+
+public:
+	Manager(Module* mod, const std::string& extname)
+		: ext(mod, extname, *this)
+	{
+	}
+
+	enum WatchResult
+	{
+		WR_OK,
+		WR_TOOMANY,
+		WR_ALREADYWATCHING,
+		WR_INVALIDNICK
+	};
+
+	WatchResult Watch(LocalUser* user, const std::string& nick, unsigned long maxwatch)
+	{
+		if (!ServerInstance->IsNick(nick))
+			return WR_INVALIDNICK;
+
+		WatchedList* watched = GetWatchedPriv(user, true);
+		if (watched->size() >= maxwatch)
+			return WR_TOOMANY;
+
+		Entry* entry = AddWatcher(nick, user);
+		if (stdalgo::isin(*watched, entry))
+			return WR_ALREADYWATCHING;
+
+		entry->watchers.push_back(user);
+		watched->push_back(entry);
+		return WR_OK;
+	}
+
+	bool Unwatch(LocalUser* user, const std::string& nick)
+	{
+		WatchedList* list = GetWatchedPriv(user);
+		if (!list)
+			return false;
+
+		bool ret = RemoveWatcher(nick, user, *list);
+		// If no longer watching any nick unset ext
+		if (list->empty())
+			ext.Unset(user);
+		return ret;
+	}
+
+	const WatchedList& GetWatched(LocalUser* user)
+	{
+		WatchedList* list = GetWatchedPriv(user);
+		if (list)
+			return *list;
+		return emptywatchedlist;
+	}
+
+	void UnwatchAll(LocalUser* user)
+	{
+		WatchedList* list = GetWatchedPriv(user);
+		if (!list)
+			return;
+
+		while (!list->empty())
+		{
+			Entry* entry = list->front();
+			RemoveWatcher(entry->GetNick(), user, *list);
+		}
+		ext.Unset(user);
+	}
+
+	WatcherList* GetWatcherList(const std::string& nick)
+	{
+		Entry* entry = Find(nick);
+		if (entry)
+			return &entry->watchers;
+		return nullptr;
+	}
+
+private:
+	typedef std::unordered_map<std::string, Entry, irc::insensitive, irc::StrHashComp> NickHash;
+
+	Entry* Find(const std::string& nick)
+	{
+		NickHash::iterator it = nicks.find(nick);
+		if (it != nicks.end())
+			return &it->second;
+		return nullptr;
+	}
+
+	Entry* AddWatcher(const std::string& nick, LocalUser* user)
+	{
+		std::pair<NickHash::iterator, bool> ret = nicks.emplace(nick, Entry());
+		Entry& entry = ret.first->second;
+		if (ret.second)
+			entry.SetNick(nick);
+		return &entry;
+	}
+
+	bool RemoveWatcher(const std::string& nick, LocalUser* user, WatchedList& watchedlist)
+	{
+		NickHash::iterator it = nicks.find(nick);
+		// If nobody is watching this nick the user trying to remove it isn't watching it for sure
+		if (it == nicks.end())
+			return false;
+
+		Entry& entry = it->second;
+		// Erase from the user's list of watched nicks
+		if (!stdalgo::vector::swaperase(watchedlist, &entry))
+			return false; // User is not watching this nick
+
+		// Erase from the nick's list of watching users
+		stdalgo::vector::swaperase(entry.watchers, user);
+
+		// If nobody else is watching the nick remove map entry
+		if (entry.watchers.empty())
+			nicks.erase(it);
+
+		return true;
+	}
+
+	WatchedList* GetWatchedPriv(LocalUser* user, bool create = false)
+	{
+		ExtData* extdata = ext.Get(user, create);
+		if (!extdata)
+			return nullptr;
+		return &extdata->list;
+	}
+
+	NickHash nicks;
+	ExtItem ext;
+	WatchedList emptywatchedlist;
+};
+
+void IRCv3::Monitor::Manager::ExtItem::FromInternal(Extensible* container, const std::string& value) noexcept
+{
+	if (container->extype != this->extype)
+		return;
+
+	irc::spacesepstream ss(value);
+	for (std::string nick; ss.GetToken(nick); )
+		manager.Watch(static_cast<LocalUser*>(container), nick, ULONG_MAX);
+}
+
+#ifndef INSPIRCD_MONITOR_MANAGER_ONLY
+
+enum
+{
+	RPL_MONONLINE = 730,
+	RPL_MONOFFLINE = 731,
+	RPL_MONLIST = 732,
+	RPL_ENDOFMONLIST = 733,
+	ERR_MONLISTFULL = 734
+};
+
+class CommandMonitor final
+	: public SplitCommand
+{
+	typedef Numeric::Builder<> ReplyBuilder;
+	// Additional penalty for the /MONITOR L and /MONITOR S commands that request a list from the server
+	static constexpr unsigned int ListPenalty = 3000;
+
+	IRCv3::Monitor::Manager& manager;
+
+	void HandlePlus(LocalUser* user, const std::string& input)
+	{
+		ReplyBuilder online(user, RPL_MONONLINE);
+		ReplyBuilder offline(user, RPL_MONOFFLINE);
+		irc::commasepstream ss(input);
+		for (std::string nick; ss.GetToken(nick); )
+		{
+			IRCv3::Monitor::Manager::WatchResult result = manager.Watch(user, nick, maxmonitor);
+			if (result == IRCv3::Monitor::Manager::WR_TOOMANY)
+			{
+				// List is full, send error which includes the remaining nicks that were not processed
+				user->WriteNumeric(ERR_MONLISTFULL, maxmonitor, fmt::format("{}{}{}", nick, (ss.StreamEnd() ? "" : ","), ss.GetRemaining()), "Monitor list is full");
+				break;
+			}
+			else if (result != IRCv3::Monitor::Manager::WR_OK)
+				continue; // Already added or invalid nick
+
+			ReplyBuilder& out = (ServerInstance->Users.FindNick(nick, true) ? online : offline);
+			out.Add(nick);
+		}
+
+		online.Flush();
+		offline.Flush();
+	}
+
+	void HandleMinus(LocalUser* user, const std::string& input)
+	{
+		irc::commasepstream ss(input);
+		for (std::string nick; ss.GetToken(nick); )
+			manager.Unwatch(user, nick);
+	}
+
+public:
+	unsigned long maxmonitor;
+
+	CommandMonitor(Module* mod, IRCv3::Monitor::Manager& managerref)
+		: SplitCommand(mod, "MONITOR", 1)
+		, manager(managerref)
+	{
+		penalty = 2000;
+		syntax = { "C", "L", "S", "(+|-) <nick>[,<nick>]+" };
+	}
+
+	CmdResult HandleLocal(LocalUser* user, const Params& parameters) override
+	{
+		char subcmd = toupper(parameters[0][0]);
+		if (subcmd == '+')
+		{
+			if (parameters.size() > 1)
+				HandlePlus(user, parameters[1]);
+		}
+		else if (subcmd == '-')
+		{
+			if (parameters.size() > 1)
+				HandleMinus(user, parameters[1]);
+		}
+		else if (subcmd == 'C')
+		{
+			manager.UnwatchAll(user);
+		}
+		else if (subcmd == 'L')
+		{
+			user->CommandFloodPenalty += ListPenalty;
+			const IRCv3::Monitor::WatchedList& list = manager.GetWatched(user);
+			ReplyBuilder out(user, RPL_MONLIST);
+			for (const auto* entry : list)
+				out.Add(entry->GetNick());
+			out.Flush();
+			user->WriteNumeric(RPL_ENDOFMONLIST, "End of MONITOR list");
+		}
+		else if (subcmd == 'S')
+		{
+			user->CommandFloodPenalty += ListPenalty;
+
+			ReplyBuilder online(user, RPL_MONONLINE);
+			ReplyBuilder offline(user, RPL_MONOFFLINE);
+
+			for (const auto* entry : manager.GetWatched(user))
+			{
+				ReplyBuilder& out = (ServerInstance->Users.FindNick(entry->GetNick(), true) ? online : offline);
+				out.Add(entry->GetNick());
+			}
+
+			online.Flush();
+			offline.Flush();
+		}
+		else
+			return CmdResult::FAILURE;
+
+		return CmdResult::SUCCESS;
+	}
+};
+
+class ModuleMonitor final
+	: public Module
+	, public ISupport::EventListener
+	, public Monitor::APIBase
+{
+private:
+	IRCv3::Monitor::Manager manager;
+	CommandMonitor cmd;
+	Cap::Capability extendedcap;
+
+	void SendAlert(unsigned int numeric, const std::string& nick)
+	{
+		const IRCv3::Monitor::WatcherList* list = manager.GetWatcherList(nick);
+		if (!list)
+			return;
+
+		for (const auto& curr : *list)
+			curr->WriteNumeric(numeric, nick);
+	}
+
+public:
+	ModuleMonitor()
+		: Module(VF_VENDOR, "Adds the /MONITOR command which allows users to find out when their friends are connected to the server.")
+		, ISupport::EventListener(this)
+		, Monitor::APIBase(this)
+		, manager(this, "monitor")
+		, cmd(this, manager)
+		, extendedcap(this, "extended-monitor")
+	{
+	}
+
+	void ReadConfig(ConfigStatus& status) override
+	{
+		const auto& tag = ServerInstance->Config->ConfValue("monitor");
+		cmd.maxmonitor = tag->getNum<unsigned long>("maxentries", 30, 1);
+	}
+
+	void OnPostConnect(User* user) override
+	{
+		SendAlert(RPL_MONONLINE, user->nick);
+	}
+
+	void OnUserPostNick(User* user, const std::string& oldnick) override
+	{
+		// Detect and ignore nickname case change
+		if (ServerInstance->Users.FindNick(oldnick) == user)
+			return;
+
+		SendAlert(RPL_MONOFFLINE, oldnick);
+		SendAlert(RPL_MONONLINE, user->nick);
+	}
+
+	void OnUserQuit(User* user, const std::string& message, const std::string& oper_message) override
+	{
+		LocalUser* localuser = IS_LOCAL(user);
+		if (localuser)
+			manager.UnwatchAll(localuser);
+		SendAlert(RPL_MONOFFLINE, user->nick);
+	}
+
+	void OnBuildISupport(ISupport::TokenMap& tokens) override
+	{
+		tokens["MONITOR"] = ConvToStr(cmd.maxmonitor);
+	}
+
+	void ForEachWatcher(User* user, Monitor::ForEachHandler& handler, bool extended_only) override
+	{
+		const IRCv3::Monitor::WatcherList* list = manager.GetWatcherList(user->nick);
+		if (!list)
+			return;
+
+		for (IRCv3::Monitor::WatcherList::const_iterator i = list->begin(); i != list->end(); ++i)
+		{
+			LocalUser* curr = *i;
+			if (!extended_only || extendedcap.IsEnabled(curr))
+				handler.Execute(curr);
+		}
+	}
+};
+
+MODULE_INIT(ModuleMonitor)
+
+#endif