[user/henk/code/inspircd.git] / include / inspircd.h

/*       +------------------------------------+
 *       | Inspire Internet Relay Chat Daemon |
 *       +------------------------------------+
 *
 *  InspIRCd: (C) 2002-2007 InspIRCd Development Team
 * See: http://www.inspircd.org/wiki/index.php/Credits
 *
 * This program is free but copyrighted software; see
 *            the file COPYING for details.
 *
 * ---------------------------------------------------
 */

#ifndef __INSPIRCD_H__
#define __INSPIRCD_H__

#include <time.h>
#include <string>
#include <sstream>
#include "inspircd_config.h"
#include "users.h"
#include "channels.h"
#include "socket.h"
#include "mode.h"
#include "socketengine.h"
#include "command_parse.h"
#include "snomasks.h"

/** Returned by some functions to indicate failure.
 */
#define ERROR -1

/** Support for librodent -
 * see http://www.chatspike.net/index.php?z=64
 */
#define ETIREDHAMSTERS EAGAIN

/** Debug levels for use with InspIRCd::Log()
 */
enum DebugLevel
{
        DEBUG           =       10,
        VERBOSE         =       20,
        DEFAULT         =       30,
        SPARSE          =       40,
        NONE            =       50,
};

/**
 * This define is used in place of strcmp when we 
 * want to check if a char* string contains only one
 * letter. Pretty fast, its just two compares and an
 * addition.
 */
#define IS_SINGLE(x,y) ( (*x == y) && (*(x+1) == 0) )

/** Delete a pointer, and NULL its value
 */
template<typename T> inline void DELETE(T* x)
{
        delete x;
        x = NULL;
}

/** Template functions to convert any input type to std::string
 */
template<typename T> inline std::string ConvNumeric(const T &in)
{
        if (in == 0) return "0";
        char res[MAXBUF];
        char* out = res;
        T quotient = in;
        while (quotient) {
                *out = "0123456789"[ std::abs( (long)quotient % 10 ) ];
                ++out;
                quotient /= 10;
        }
        if ( in < 0)
                *out++ = '-';
        *out = 0;
        std::reverse(res,out);
        return res;
}

inline std::string ConvToStr(const int in)
{
        return ConvNumeric(in);
}

inline std::string ConvToStr(const long in)
{
        return ConvNumeric(in);
}

inline std::string ConvToStr(const unsigned long in)
{
        return ConvNumeric(in);
}

inline std::string ConvToStr(const char* in)
{
        return in;
}

inline std::string ConvToStr(const bool in)
{
        return (in ? "1" : "0");
}

inline std::string ConvToStr(char in)
{
        return std::string(in,1);
}

template <class T> inline std::string ConvToStr(const T &in)
{
        std::stringstream tmp;
        if (!(tmp << in)) return std::string();
        return tmp.str();
}

template<typename T> inline long ConvToInt(const T &in)
{
        std::stringstream tmp;
        if (!(tmp << in)) return 0;
        return atoi(tmp.str().c_str());
}

/** Template function to convert integer to char, storing result in *res and
 * also returning the pointer to res. Based on Stuart Lowe's C/C++ Pages.
 */
template<typename T, typename V, typename R> inline char* itoa(const T &in, V *res, R base)
{
        if (base < 2 || base > 16) { *res = 0; return res; }
        char* out = res;
        int quotient = in;
        while (quotient) {
                *out = "0123456789abcdef"[ std::abs( quotient % base ) ];
                ++out;
                quotient /= base;
        }
        if ( in < 0 && base == 10) *out++ = '-';
        std::reverse( res, out );
        *out = 0;
        return res;
}

/** This class contains various STATS counters
 * It is used by the InspIRCd class, which internally
 * has an instance of it.
 */
class serverstats : public classbase
{
  public:
        /** Number of accepted connections
         */
        unsigned long statsAccept;
        /** Number of failed accepts
         */
        unsigned long statsRefused;
        /** Number of unknown commands seen
         */
        unsigned long statsUnknown;
        /** Number of nickname collisions handled
         */
        unsigned long statsCollisions;
        /** Number of DNS queries sent out
         */
        unsigned long statsDns;
        /** Number of good DNS replies received
         * NOTE: This may not tally to the number sent out,
         * due to timeouts and other latency issues.
         */
        unsigned long statsDnsGood;
        /** Number of bad (negative) DNS replies received
         * NOTE: This may not tally to the number sent out,
         * due to timeouts and other latency issues.
         */
        unsigned long statsDnsBad;
        /** Number of inbound connections seen
         */
        unsigned long statsConnects;
        /** Total bytes of data transmitted
         */
        double statsSent;
        /** Total bytes of data received
         */
        double statsRecv;
        /** Number of bound listening ports
         */
        unsigned long BoundPortCount;

        /** Cpu usage at last sample
         */
        timeval LastCPU;

        /** Time last sample was read
         */
        timeval LastSampled;

        /** The constructor initializes all the counts to zero
         */
        serverstats()
                : statsAccept(0), statsRefused(0), statsUnknown(0), statsCollisions(0), statsDns(0),
                statsDnsGood(0), statsDnsBad(0), statsConnects(0), statsSent(0.0), statsRecv(0.0),
                BoundPortCount(0)
        {
        }
};

class InspIRCd;

/** This class implements a nonblocking log-writer.
 * Most people writing an ircd give little thought to their disk
 * i/o. On a congested system, disk writes can block for long
 * periods of time (e.g. if the system is busy and/or swapping
 * a lot). If we just use a blocking fprintf() call, this could
 * block for undesirable amounts of time (half of a second through
 * to whole seconds). We DO NOT want this, so we make our logfile
 * nonblocking and hook it into the SocketEngine.
 * NB: If the operating system does not support nonblocking file
 * I/O (linux seems to, as does freebsd) this will default to
 * blocking behaviour.
 */
class FileLogger : public EventHandler
{
 protected:
        /** The creator/owner of this object
         */
        InspIRCd* ServerInstance;
        /** The log file (fd is inside this somewhere,
         * we get it out with fileno())
         */
        FILE* log;
        /** Buffer of pending log lines to be written
         */
        std::string buffer;
        /** Number of write operations that have occured
         */
        int writeops;
 public:
        /** The constructor takes an already opened logfile.
         */
        FileLogger(InspIRCd* Instance, FILE* logfile);
        /** This returns false, logfiles are writeable.
         */
        virtual bool Readable();
        /** Handle pending write events.
         * This will flush any waiting data to disk.
         * If any data remains after the fprintf call,
         * another write event is scheduled to write
         * the rest of the data when possible.
         */
        virtual void HandleEvent(EventType et, int errornum = 0);
        /** Write one or more preformatted log lines.
         * If the data cannot be written immediately,
         * this class will insert itself into the
         * SocketEngine, and register a write event,
         * and when the write event occurs it will
         * attempt again to write the data.
         */
        void WriteLogLine(const std::string &line);
        /** Close the log file and cancel any events.
         */
        virtual void Close();
        /** Close the log file and cancel any events.
         * (indirectly call Close()
         */
        virtual ~FileLogger();
};

/** A list of failed port bindings, used for informational purposes on startup */
typedef std::vector<std::pair<std::string, long> > FailedPortList;

/** A list of ip addresses cross referenced against clone counts */
typedef std::map<irc::string, unsigned int> clonemap;

class XLineManager;

/** The main class of the irc server.
 * This class contains instances of all the other classes
 * in this software, with the exception of the base class,
 * classbase. Amongst other things, it contains a ModeParser,
 * a DNS object, a CommandParser object, and a list of active
 * Module objects, and facilities for Module objects to
 * interact with the core system it implements. You should
 * NEVER attempt to instantiate a class of type InspIRCd
 * yourself. If you do, this is equivalent to spawning a second
 * IRC server, and could have catastrophic consequences for the
 * program in terms of ram usage (basically, you could create
 * an obese forkbomb built from recursively spawning irc servers!)
 */
class InspIRCd : public classbase
{
 private:
        /** Holds a string describing the last module error to occur
         */
        char MODERR[MAXBUF];
 
        /** Remove a ModuleFactory pointer
         * @param j Index number of the ModuleFactory to remove
         */
        void EraseFactory(int j);

        /** Remove a Module pointer
         * @param j Index number of the Module to remove
         */
        void EraseModule(int j);

        /** Build the ISUPPORT string by triggering all modules On005Numeric events
         */
        void BuildISupport();

        /** Move a given module to a specific slot in the list
         * @param modulename The module name to relocate
         * @param slot The slot to move the module into
         */
        void MoveTo(std::string modulename,int slot);

        /** Display the startup banner
         */
        void Start();

        /** Set up the signal handlers
         */
        void SetSignals();

        /** Daemonize the ircd and close standard input/output streams
         * @return True if the program daemonized succesfully
         */
        bool DaemonSeed();

        /** Moves the given module to the last slot in the list
         * @param modulename The module name to relocate
         */
        void MoveToLast(std::string modulename);

        /** Moves the given module to the first slot in the list
         * @param modulename The module name to relocate
         */
        void MoveToFirst(std::string modulename);

        /** Moves one module to be placed after another in the list
         * @param modulename The module name to relocate
         * @param after The module name to place the module after
         */
        void MoveAfter(std::string modulename, std::string after);

        /** Moves one module to be placed before another in the list
         * @param modulename The module name to relocate
         * @param after The module name to place the module before
         */
        void MoveBefore(std::string modulename, std::string before);

        /** Iterate the list of InspSocket objects, removing ones which have timed out
         * @param TIME the current time
         */
        void DoSocketTimeouts(time_t TIME);

        /** Perform background user events such as PING checks
         * @param TIME the current time
         */
        void DoBackgroundUserStuff(time_t TIME);

        /** Returns true when all modules have done pre-registration checks on a user
         * @param user The user to verify
         * @return True if all modules have finished checking this user
         */
        bool AllModulesReportReady(userrec* user);

        /** Total number of modules loaded into the ircd, minus one
         */
        int ModCount;

        /** Logfile pathname specified on the commandline, or empty string
         */
        char LogFileName[MAXBUF];

        /** The feature names published by various modules
         */
        featurelist Features;

        /** The interface names published by various modules
         */
        interfacelist Interfaces;

        /** The current time, updated in the mainloop
         */
        time_t TIME;

        /** The time that was recorded last time around the mainloop
         */
        time_t OLDTIME;

        /** A 64k buffer used to read client lines into
         */
        char ReadBuffer[65535];

        /** Number of seconds in a minute
         */
        const long duration_m;

        /** Number of seconds in an hour
         */
        const long duration_h;

        /** Number of seconds in a day
         */
        const long duration_d;

        /** Number of seconds in a week
         */
        const long duration_w;

        /** Number of seconds in a year
         */
        const long duration_y;

        /** Used when connecting clients
         */
        insp_sockaddr client, server;

        /** Used when connecting clients
         */
        socklen_t length;

        /** Nonblocking file writer
         */
        FileLogger* Logger;

        /** Time offset in seconds
         * This offset is added to all calls to Time(). Use SetTimeDelta() to update
         */
        int time_delta;

 public:

        /** Number of unregistered users online right now.
         * (Unregistered means before USER/NICK/dns)
         */
        int unregistered_count;

        /** List of server names we've seen.
         */
        servernamelist servernames;

        /** Time this ircd was booted
         */
        time_t startup_time;

        /** Mode handler, handles mode setting and removal
         */
        ModeParser* Modes;

        /** Command parser, handles client to server commands
         */
        CommandParser* Parser;

        /** Socket engine, handles socket activity events
         */
        SocketEngine* SE;

        /** Stats class, holds miscellaneous stats counters
         */
        serverstats* stats;

        /**  Server Config class, holds configuration file data
         */
        ServerConfig* Config;

        /** Snomask manager - handles routing of snomask messages
         * to opers.
         */
        SnomaskManager* SNO;

        /** Client list, a hash_map containing all clients, local and remote
         */
        user_hash* clientlist;

        /** Channel list, a hash_map containing all channels
         */
        chan_hash* chanlist;

        /** Local client list, a vector containing only local clients
         */
        std::vector<userrec*> local_users;

        /** Oper list, a vector containing all local and remote opered users
         */
        std::vector<userrec*> all_opers;

        clonemap local_clones;

        clonemap global_clones;

        /** DNS class, provides resolver facilities to the core and modules
         */
        DNS* Res;

        /** Timer manager class, triggers InspTimer timer events
         */
        TimerManager* Timers;

        /** X-Line manager. Handles G/K/Q/E line setting, removal and matching
         */
        XLineManager* XLines;

        /** A list of Module* module classes
         * Note that this list is always exactly 255 in size.
         * The actual number of loaded modules is available from GetModuleCount()
         */
        ModuleList modules;

        /** A list of ModuleFactory* module factories
         * Note that this list is always exactly 255 in size.
         * The actual number of loaded modules is available from GetModuleCount()
         */
        FactoryList factory;

        /** The time we next call our ping timeout and reg timeout checks
         */
        time_t next_call;

        /** Get the current time
         * Because this only calls time() once every time around the mainloop,
         * it is much faster than calling time() directly.
         * @param delta True to use the delta as an offset, false otherwise
         * @return The current time as an epoch value (time_t)
         */
        time_t Time(bool delta = false);

        /** Set the time offset in seconds
         * This offset is added to Time() to offset the system time by the specified
         * number of seconds.
         * @param delta The number of seconds to offset
         * @return The old time delta
         */
        int SetTimeDelta(int delta);

        void AddLocalClone(userrec* user);

        void AddGlobalClone(userrec* user);

        /** Number of users with a certain mode set on them
         */
        int ModeCount(const char mode);

        /** Get the time offset in seconds
         * @return The current time delta (in seconds)
         */
        int GetTimeDelta();

        /** Process a user whos socket has been flagged as active
         * @param cu The user to process
         * @return There is no actual return value, however upon exit, the user 'cu' may have been deleted
         */
        void ProcessUser(userrec* cu);

        /** Get the total number of currently loaded modules
         * @return The number of loaded modules
         */
        int GetModuleCount();

        /** Find a module by name, and return a Module* to it.
         * This is preferred over iterating the module lists yourself.
         * @param name The module name to look up
         * @return A pointer to the module, or NULL if the module cannot be found
         */
        Module* FindModule(const std::string &name);

        /** Bind all ports specified in the configuration file.
         * @param bail True if the function should bail back to the shell on failure
         * @param found_ports The actual number of ports found in the config, as opposed to the number actually bound
         * @return The number of ports actually bound without error
         */
        int BindPorts(bool bail, int &found_ports, FailedPortList &failed_ports);

        /** Returns true if this server has the given port bound to the given address
         * @param port The port number
         * @param addr The address
         * @return True if we have a port listening on this address
         */
        bool HasPort(int port, char* addr);

        /** Binds a socket on an already open file descriptor
         * @param sockfd A valid file descriptor of an open socket
         * @param client A sockaddr to use as temporary storage
         * @param server A sockaddr to use as temporary storage
         * @param port The port number to bind to
         * @param addr The address to bind to (IP only)
         * @return True if the port was bound successfully
         */
        bool BindSocket(int sockfd, insp_sockaddr client, insp_sockaddr server, int port, char* addr);

        /** Adds a server name to the list of servers we've seen
         * @param The servername to add
         */
        void AddServerName(const std::string &servername);

        /** Finds a cached char* pointer of a server name,
         * This is used to optimize userrec by storing only the pointer to the name
         * @param The servername to find
         * @return A pointer to this name, gauranteed to never become invalid
         */
        const char* FindServerNamePtr(const std::string &servername);

        /** Returns true if we've seen the given server name before
         * @param The servername to find
         * @return True if we've seen this server name before
         */
        bool FindServerName(const std::string &servername);

        /** Gets the GECOS (description) field of the given server.
         * If the servername is not that of the local server, the name
         * is passed to handling modules which will attempt to determine
         * the GECOS that bleongs to the given servername.
         * @param servername The servername to find the description of
         * @return The description of this server, or of the local server
         */
        std::string GetServerDescription(const char* servername);

        /** Write text to all opers connected to this server
         * @param text The text format string
         * @param ... Format args
         */
        void WriteOpers(const char* text, ...);

        /** Write text to all opers connected to this server
         * @param text The text to send
         */
        void WriteOpers(const std::string &text);
        
        /** Find a nickname in the nick hash
         * @param nick The nickname to find
         * @return A pointer to the user, or NULL if the user does not exist
         */
        userrec* FindNick(const std::string &nick);

        /** Find a nickname in the nick hash
         * @param nick The nickname to find
         * @return A pointer to the user, or NULL if the user does not exist
         */
        userrec* FindNick(const char* nick);

        /** Find a channel in the channels hash
         * @param chan The channel to find
         * @return A pointer to the channel, or NULL if the channel does not exist
         */
        chanrec* FindChan(const std::string &chan);

        /** Find a channel in the channels hash
         * @param chan The channel to find
         * @return A pointer to the channel, or NULL if the channel does not exist
         */
        chanrec* FindChan(const char* chan);

        /** Called by the constructor to load all modules from the config file.
         */
        void LoadAllModules();

        /** Check for a 'die' tag in the config file, and abort if found
         * @return Depending on the configuration, this function may never return
         */
        void CheckDie();

        /** Check we aren't running as root, and exit if we are
         * @return Depending on the configuration, this function may never return
         */
        void CheckRoot();

        /** Determine the right path for, and open, the logfile
         * @param argv The argv passed to main() initially, used to calculate program path
         * @param argc The argc passed to main() initially, used to calculate program path
         */
        void OpenLog(char** argv, int argc);

        void CloseLog();

        /** Convert a user to a pseudoclient, disconnecting the real user
         * @param user The user to convert
         * @param message The quit message to display when exiting the user
         * @return True if the operation succeeded
         */
        bool UserToPseudo(userrec* user, const std::string &message);

        /** Convert a pseudoclient to a real user, discarding the pseudoclient
         * @param alive A live client
         * @param zombie A pseudoclient
         * @param message The message to display when quitting the pseudoclient
         * @return True if the operation succeeded
         */
        bool PseudoToUser(userrec* alive, userrec* zombie, const std::string &message);

        /** Send a server notice to all local users
         * @param text The text format string to send
         * @param ... The format arguments
         */
        void ServerNoticeAll(char* text, ...);

        /** Send a server message (PRIVMSG) to all local users
         * @param text The text format string to send
         * @param ... The format arguments
         */
        void ServerPrivmsgAll(char* text, ...);

        /** Send text to all users with a specific set of modes
         * @param modes The modes to check against, without a +, e.g. 'og'
         * @param flags one of WM_OR or WM_AND. If you specify WM_OR, any one of the 
         * mode characters in the first parameter causes receipt of the message, and
         * if you specify WM_OR, all the modes must be present.
         * @param text The text format string to send
         * @param ... The format arguments
         */
        void WriteMode(const char* modes, int flags, const char* text, ...);

        /** Return true if a channel name is valid
         * @param chname A channel name to verify
         * @return True if the name is valid
         */
        bool IsChannel(const char *chname);

        /** Rehash the local server
         * @param status This value is unused, and required for signal handler functions
         */
        static void Rehash(int status);

        /** Causes the server to exit immediately
         * @param The exit code to give to the operating system
         * (See the ExitStatus enum for valid values)
         */
        static void Exit(int status);

        /** Return a count of users, unknown and known connections
         * @return The number of users
         */
        int UserCount();

        /** Return a count of fully registered connections only
         * @return The number of registered users
         */
        int RegisteredUserCount();

        /** Return a count of invisible (umode +i) users only
         * @return The number of invisible users
         */
        int InvisibleUserCount();

        /** Return a count of opered (umode +o) users only
         * @return The number of opers
         */
        int OperCount();

        /** Return a count of unregistered (before NICK/USER) users only
         * @return The number of unregistered (unknown) connections
         */
        int UnregisteredUserCount();

        /** Return a count of channels on the network
         * @return The number of channels
         */
        long ChannelCount();

        /** Return a count of local users on this server only
         * @return The number of local users
         */
        long LocalUserCount();

        /** Send an error notice to all local users, opered and unopered
         * @param s The error string to send
         */
        void SendError(const std::string &s);

        /** For use with Module::Prioritize().
         * When the return value of this function is returned from
         * Module::Prioritize(), this specifies that the module wishes
         * to be ordered exactly BEFORE 'modulename'. For more information
         * please see Module::Prioritize().
         * @param modulename The module your module wants to be before in the call list
         * @returns a priority ID which the core uses to relocate the module in the list
         */
        long PriorityBefore(const std::string &modulename);

        /** For use with Module::Prioritize().
         * When the return value of this function is returned from
         * Module::Prioritize(), this specifies that the module wishes
         * to be ordered exactly AFTER 'modulename'. For more information please
         * see Module::Prioritize().
         * @param modulename The module your module wants to be after in the call list
         * @returns a priority ID which the core uses to relocate the module in the list
         */
        long PriorityAfter(const std::string &modulename);

        /** Publish a 'feature'.
         * There are two ways for a module to find another module it depends on.
         * Either by name, using InspIRCd::FindModule, or by feature, using this
         * function. A feature is an arbitary string which identifies something this
         * module can do. For example, if your module provides SSL support, but other
         * modules provide SSL support too, all the modules supporting SSL should
         * publish an identical 'SSL' feature. This way, any module requiring use
         * of SSL functions can just look up the 'SSL' feature using FindFeature,
         * then use the module pointer they are given.
         * @param FeatureName The case sensitive feature name to make available
         * @param Mod a pointer to your module class
         * @returns True on success, false if the feature is already published by
         * another module.
         */
        bool PublishFeature(const std::string &FeatureName, Module* Mod);

        /** Publish a module to an 'interface'.
         * Modules which implement the same interface (the same way of communicating
         * with other modules) can publish themselves to an interface, using this
         * method. When they do so, they become part of a list of related or
         * compatible modules, and a third module may then query for that list
         * and know that all modules within that list offer the same API.
         * A prime example of this is the hashing modules, which all accept the
         * same types of Request class. Consider this to be similar to PublishFeature,
         * except for that multiple modules may publish the same 'feature'.
         * @param InterfaceName The case sensitive interface name to make available
         * @param Mod a pointer to your module class
         * @returns True on success, false on failure (there are currently no failure
         * cases)
         */
        bool PublishInterface(const std::string &InterfaceName, Module* Mod);

        /** Return a pair saying how many other modules are currently using the
         * interfaces provided by module m.
         * @param m The module to count usage for
         * @return A pair, where the first value is the number of uses of the interface,
         * and the second value is the interface name being used.
         */
        std::pair<int,std::string> GetInterfaceInstanceCount(Module* m);

        /** Mark your module as using an interface.
         * If you mark your module as using an interface, then that interface
         * module may not unload until your module has unloaded first.
         * This can be used to prevent crashes by ensuring code you depend on
         * is always in memory while your module is active.
         * @param InterfaceName The interface to use
         */
        void UseInterface(const std::string &InterfaceName);

        /** Mark your module as finished with an interface.
         * If you used UseInterface() above, you should use this method when
         * your module is finished with the interface (usually in its destructor)
         * to allow the modules which implement the given interface to be unloaded.
         * @param InterfaceName The interface you are finished with using.
         */
        void DoneWithInterface(const std::string &InterfaceName);

        /** Unpublish a 'feature'.
         * When your module exits, it must call this method for every feature it
         * is providing so that the feature table is cleaned up.
         * @param FeatureName the feature to remove
         */
        bool UnpublishFeature(const std::string &FeatureName);

        /** Unpublish your module from an interface
         * When your module exits, it must call this method for every interface
         * it is part of so that the interfaces table is cleaned up. Only when
         * the last item is deleted from an interface does the interface get
         * removed.
         * @param InterfaceName the interface to be removed from
         * @param Mod The module to remove from the interface list
         */
        bool UnpublishInterface(const std::string &InterfaceName, Module* Mod);

        /** Find a 'feature'.
         * There are two ways for a module to find another module it depends on.
         * Either by name, using InspIRCd::FindModule, or by feature, using the
         * InspIRCd::PublishFeature method. A feature is an arbitary string which
         * identifies something this module can do. For example, if your module
         * provides SSL support, but other modules provide SSL support too, all
         * the modules supporting SSL should publish an identical 'SSL' feature.
         * To find a module capable of providing the feature you want, simply
         * call this method with the feature name you are looking for.
         * @param FeatureName The feature name you wish to obtain the module for
         * @returns A pointer to a valid module class on success, NULL on failure.
         */
        Module* FindFeature(const std::string &FeatureName);

        /** Find an 'interface'.
         * An interface is a list of modules which all implement the same API.
         * @param InterfaceName The Interface you wish to obtain the module
         * list of.
         * @return A pointer to a deque of Module*, or NULL if the interface
         * does not exist.
         */
        modulelist* FindInterface(const std::string &InterfaceName);

        /** Given a pointer to a Module, return its filename
         * @param m The module pointer to identify
         * @return The module name or an empty string
         */
        const std::string& GetModuleName(Module* m);

        /** Return true if a nickname is valid
         * @param n A nickname to verify
         * @return True if the nick is valid
         */
        bool IsNick(const char* n);

        /** Return true if an ident is valid
         * @param An ident to verify
         * @return True if the ident is valid
         */
        bool IsIdent(const char* n);

        /** Find a username by their file descriptor.
         * It is preferred to use this over directly accessing the fd_ref_table array.
         * @param socket The file descriptor of a user
         * @return A pointer to the user if the user exists locally on this descriptor
         */
        userrec* FindDescriptor(int socket);

        /** Add a new mode to this server's mode parser
         * @param mh The modehandler to add
         * @param modechar The mode character this modehandler handles
         * @return True if the mode handler was added
         */
        bool AddMode(ModeHandler* mh, const unsigned char modechar);

        /** Add a new mode watcher to this server's mode parser
         * @param mw The modewatcher to add
         * @return True if the modewatcher was added
         */
        bool AddModeWatcher(ModeWatcher* mw);

        /** Delete a mode watcher from this server's mode parser
         * @param mw The modewatcher to delete
         * @return True if the modewatcher was deleted
         */
        bool DelModeWatcher(ModeWatcher* mw);

        /** Add a dns Resolver class to this server's active set
         * @param r The resolver to add
         * @param cached If this value is true, then the cache will
         * be searched for the DNS result, immediately. If the value is
         * false, then a request will be sent to the nameserver, and the
         * result will not be immediately available. You should usually
         * use the boolean value which you passed to the Resolver
         * constructor, which Resolver will set appropriately depending
         * on if cached results are available and haven't expired. It is
         * however safe to force this value to false, forcing a remote DNS
         * lookup, but not an update of the cache.
         * @return True if the operation completed successfully. Note that
         * if this method returns true, you should not attempt to access
         * the resolver class you pass it after this call, as depending upon
         * the request given, the object may be deleted!
         */
        bool AddResolver(Resolver* r, bool cached);

        /** Add a command to this server's command parser
         * @param f A command_t command handler object to add
         * @throw ModuleException Will throw ModuleExcption if the command already exists
         */
        void AddCommand(command_t *f);

        /** Send a modechange.
         * The parameters provided are identical to that sent to the
         * handler for class cmd_mode.
         * @param parameters The mode parameters
         * @param pcnt The number of items you have given in the first parameter
         * @param user The user to send error messages to
         */
        void SendMode(const char **parameters, int pcnt, userrec *user);

        /** Match two strings using pattern matching.
         * This operates identically to the global function match(),
         * except for that it takes std::string arguments rather than
         * const char* ones.
         * @param sliteral The literal string to match against
         * @param spattern The pattern to match against. CIDR and globs are supported.
         */
        bool MatchText(const std::string &sliteral, const std::string &spattern);

        /** Call the handler for a given command.
         * @param commandname The command whos handler you wish to call
         * @param parameters The mode parameters
         * @param pcnt The number of items you have given in the first parameter
         * @param user The user to execute the command as
         * @return True if the command handler was called successfully
         */
        bool CallCommandHandler(const std::string &commandname, const char** parameters, int pcnt, userrec* user);

        /** Return true if the command is a module-implemented command and the given parameters are valid for it
         * @param parameters The mode parameters
         * @param pcnt The number of items you have given in the first parameter
         * @param user The user to test-execute the command as
         * @return True if the command handler is a module command, and there are enough parameters and the user has permission to the command
         */
        bool IsValidModuleCommand(const std::string &commandname, int pcnt, userrec* user);

        /** Add a gline and apply it
         * @param duration How long the line should last
         * @param source Who set the line
         * @param reason The reason for the line
         * @param hostmask The hostmask to set the line against
         */
        void AddGLine(long duration, const std::string &source, const std::string &reason, const std::string &hostmask);

        /** Add a qline and apply it
         * @param duration How long the line should last
         * @param source Who set the line
         * @param reason The reason for the line
         * @param nickname The nickmask to set the line against
         */
        void AddQLine(long duration, const std::string &source, const std::string &reason, const std::string &nickname);

        /** Add a zline and apply it
         * @param duration How long the line should last
         * @param source Who set the line
         * @param reason The reason for the line
         * @param ipaddr The ip-mask to set the line against
         */
        void AddZLine(long duration, const std::string &source, const std::string &reason, const std::string &ipaddr);

        /** Add a kline and apply it
         * @param duration How long the line should last
         * @param source Who set the line
         * @param reason The reason for the line
         * @param hostmask The hostmask to set the line against
         */
        void AddKLine(long duration, const std::string &source, const std::string &reason, const std::string &hostmask);

        /** Add an eline
         * @param duration How long the line should last
         * @param source Who set the line
         * @param reason The reason for the line
         * @param hostmask The hostmask to set the line against
         */
        void AddELine(long duration, const std::string &source, const std::string &reason, const std::string &hostmask);

        /** Delete a gline
         * @param hostmask The gline to delete
         * @return True if the item was removed
         */
        bool DelGLine(const std::string &hostmask);

        /** Delete a qline
         * @param nickname The qline to delete
         * @return True if the item was removed
         */
        bool DelQLine(const std::string &nickname);

        /** Delete a zline
         * @param ipaddr The zline to delete
         * @return True if the item was removed
         */
        bool DelZLine(const std::string &ipaddr);

        /** Delete a kline
         * @param hostmask The kline to delete
         * @return True if the item was removed
         */
        bool DelKLine(const std::string &hostmask);

        /** Delete an eline
         * @param hostmask The kline to delete
         * @return True if the item was removed
         */
        bool DelELine(const std::string &hostmask);

        /** Return true if the given parameter is a valid nick!user\@host mask
         * @param mask A nick!user\@host masak to match against 
         * @return True i the mask is valid
         */
        bool IsValidMask(const std::string &mask);

        /** Rehash the local server
         */
        void RehashServer();

        /** Return the channel whos index number matches that provided
         * @param The index number of the channel to fetch
         * @return A channel record, or NUll if index < 0 or index >= InspIRCd::ChannelCount()
         */
        chanrec* GetChannelIndex(long index);

        /** Dump text to a user target, splitting it appropriately to fit
         * @param User the user to dump the text to
         * @param LinePrefix text to prefix each complete line with
         * @param TextStream the text to send to the user
         */
        void DumpText(userrec* User, const std::string &LinePrefix, stringstream &TextStream);

        /** Check if the given nickmask matches too many users, send errors to the given user
         * @param nick A nickmask to match against
         * @param user A user to send error text to
         * @return True if the nick matches too many users
         */
        bool NickMatchesEveryone(const std::string &nick, userrec* user);

        /** Check if the given IP mask matches too many users, send errors to the given user
         * @param ip An ipmask to match against
         * @param user A user to send error text to
         * @return True if the ip matches too many users
         */
        bool IPMatchesEveryone(const std::string &ip, userrec* user);

        /** Check if the given hostmask matches too many users, send errors to the given user
         * @param mask A hostmask to match against
         * @param user A user to send error text to
         * @return True if the host matches too many users
         */
        bool HostMatchesEveryone(const std::string &mask, userrec* user);

        /** Calculate a duration in seconds from a string in the form 1y2w3d4h6m5s
         * @param str A string containing a time in the form 1y2w3d4h6m5s
         * (one year, two weeks, three days, four hours, six minutes and five seconds)
         * @return The total number of seconds
         */
        long Duration(const char* str);

        /** Attempt to compare an oper password to a string from the config file.
         * This will be passed to handling modules which will compare the data
         * against possible hashed equivalents in the input string.
         * @param data The data from the config file
         * @param input The data input by the oper
         * @param tagnum the tag number of the oper's tag in the config file
         * @return 0 if the strings match, 1 or -1 if they do not
         */
        int OperPassCompare(const char* data,const char* input, int tagnum);

        /** Check if a given server is a uline.
         * An empty string returns true, this is by design.
         * @param server The server to check for uline status
         * @return True if the server is a uline OR the string is empty
         */
        bool ULine(const char* server);

        /** Returns the subversion revision ID of this ircd
         * @return The revision ID or an empty string
         */
        std::string GetRevision();

        /** Returns the full version string of this ircd
         * @return The version string
         */
        std::string GetVersionString();

        /** Attempt to write the process id to a given file
         * @param filename The PID file to attempt to write to
         * @return This function may bail if the file cannot be written
         */
        void WritePID(const std::string &filename);

        /** Returns text describing the last module error
         * @return The last error message to occur
         */
        char* ModuleError();

        /** Load a given module file
         * @param filename The file to load
         * @return True if the module was found and loaded
         */
        bool LoadModule(const char* filename);

        /** Unload a given module file
         * @param filename The file to unload
         * @return True if the module was unloaded
         */
        bool UnloadModule(const char* filename);

        /** This constructor initialises all the subsystems and reads the config file.
         * @param argc The argument count passed to main()
         * @param argv The argument list passed to main()
         * @throw <anything> If anything is thrown from here and makes it to
         * you, you should probably just give up and go home. Yes, really.
         * It's that bad. Higher level classes should catch any non-fatal exceptions.
         */
        InspIRCd(int argc, char** argv);

        /** Do one iteration of the mainloop
         * @param process_module_sockets True if module sockets are to be processed
         * this time around the event loop. The is the default.
         */
        void DoOneIteration(bool process_module_sockets = true);

        /** Output a log message to the ircd.log file
         * The text will only be output if the current loglevel
         * is less than or equal to the level you provide
         * @param level A log level from the DebugLevel enum
         * @param text Format string of to write to the log
         * @param ... Format arguments of text to write to the log
         */
        void Log(int level, const char* text, ...);

        /** Output a log message to the ircd.log file
         * The text will only be output if the current loglevel
         * is less than or equal to the level you provide
         * @param level A log level from the DebugLevel enum
         * @param text Text to write to the log
         */
        void Log(int level, const std::string &text);

        void SendWhoisLine(userrec* user, userrec* dest, int numeric, const std::string &text);

        void SendWhoisLine(userrec* user, userrec* dest, int numeric, const char* format, ...);

        /** Restart the server.
         * This function will not return. If an error occurs,
         * it will throw an instance of CoreException.
         * @param reason The restart reason to show to all clients
         * @throw CoreException An instance of CoreException indicating the error from execv().
         */
        void Restart(const std::string &reason);

        /** Prepare the ircd for restart or shutdown.
         * This function unloads all modules which can be unloaded,
         * closes all open sockets, and closes the logfile.
         */
        void Cleanup();

        /** This copies the user and channel hash_maps into new hash maps.
         * This frees memory used by the hash_map allocator (which it neglects
         * to free, most of the time, using tons of ram)
         */
        void RehashUsersAndChans();

        /** Resets the cached max bans value on all channels.
         * Called by rehash.
         */
        void ResetMaxBans();

        /** Begin execution of the server.
         * NOTE: this function NEVER returns. Internally,
         * after performing some initialisation routines,
         * it will repeatedly call DoOneIteration in a loop.
         * @return The return value for this function is undefined.
         */
        int Run();
};

#endif