/dep/include/sockets/SocketHandler.h

/** \file SocketHandler.h
 ** \date  2004-02-13
 ** \author grymse@alhem.net
**/
/*
Copyright (C) 2004-2007  Anders Hedstrom

This library is made available under the terms of the GNU GPL.

If you would like to use this library in a closed-source application,
a separate license agreement is available. For information about
the closed-source license agreement for the C++ sockets library,
please visit http://www.alhem.net/Sockets/license.html and/or
email license@alhem.net.

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
*/
#ifndef _SOCKETS_SocketHandler_H
#define _SOCKETS_SocketHandler_H

#include "sockets-config.h"
#include <map>
#include <list>

#include "socket_include.h"
#include "ISocketHandler.h"

#ifdef SOCKETS_NAMESPACE
namespace SOCKETS_NAMESPACE {
#endif


class Socket;
#ifdef ENABLE_RESOLVER
class ResolvServer;
#endif
class Mutex;

/** Socket container class, event generator.
    \ingroup basic */
class SocketHandler : public ISocketHandler
{
protected:
    /** Map type for holding file descriptors/socket object pointers. */
    typedef std::map<SOCKET,Socket *> socket_m;

public:
    /** SocketHandler constructor.
        \param log Optional log class pointer */
    SocketHandler(StdLog *log = NULL);

    /** SocketHandler threadsafe constructor.
        \param mutex Externally declared mutex variable
        \param log Optional log class pointer */
    SocketHandler(Mutex& mutex,StdLog *log = NULL);

    ~SocketHandler();

    /** Get mutex reference for threadsafe operations. */
    Mutex& GetMutex() const;

    /** Register StdLog object for error callback.
        \param log Pointer to log class */
    void RegStdLog(StdLog *log);

    /** Log error to log class for print out / storage. */
    void LogError(Socket *p,const std::string& user_text,int err,const std::string& sys_err,loglevel_t t = LOG_LEVEL_WARNING);

    /** Add socket instance to socket map. Removal is always automatic. */
    void Add(Socket *);

    /** Get status of read/write/exception file descriptor set for a socket. */
    void Get(SOCKET s,bool& r,bool& w,bool& e);

    /** Set read/write/exception file descriptor sets (fd_set). */
    void Set(SOCKET s,bool bRead,bool bWrite,bool bException = true);

    /** Wait for events, generate callbacks. */
    int Select(long sec,long usec);

    /** This method will not return until an event has been detected. */
    int Select();

    /** Wait for events, generate callbacks. */
    int Select(struct timeval *tsel);

    /** Check that a socket really is handled by this socket handler. */
    bool Valid(Socket *);

    /** Return number of sockets handled by this handler.  */
    size_t GetCount();

    /** Override and return false to deny all incoming connections.
        \param p ListenSocket class pointer (use GetPort to identify which one) */
    bool OkToAccept(Socket *p);

    /** Called by Socket when a socket changes state. */
    void AddList(SOCKET s,list_t which_one,bool add);

    // Connection pool
#ifdef ENABLE_POOL
    /** Find available open connection (used by connection pool). */
    ISocketHandler::PoolSocket *FindConnection(int type,const std::string& protocol,SocketAddress&);
    /** Enable connection pool (by default disabled). */
    void EnablePool(bool x = true);
    /** Check pool status.
        \return true if connection pool is enabled */
    bool PoolEnabled();
#endif // ENABLE_POOL

    // Socks4
#ifdef ENABLE_SOCKS4
    /** Set socks4 server ip that all new tcp sockets should use. */
    void SetSocks4Host(ipaddr_t);
    /** Set socks4 server hostname that all new tcp sockets should use. */
    void SetSocks4Host(const std::string& );
    /** Set socks4 server port number that all new tcp sockets should use. */
    void SetSocks4Port(port_t);
    /** Set optional socks4 userid. */
    void SetSocks4Userid(const std::string& );
    /** If connection to socks4 server fails, immediately try direct connection to final host. */
    void SetSocks4TryDirect(bool x = true);
    /** Get socks4 server ip.
        \return socks4 server ip */
    ipaddr_t GetSocks4Host();
    /** Get socks4 port number.
        \return socks4 port number */
    port_t GetSocks4Port();
    /** Get socks4 userid (optional).
        \return socks4 userid */
    const std::string& GetSocks4Userid();
    /** Check status of socks4 try direct flag.
        \return true if direct connection should be tried if connection to socks4 server fails */
    bool Socks4TryDirect();
#endif // ENABLE_SOCKS4

    // DNS resolve server
#ifdef ENABLE_RESOLVER
    /** Enable asynchronous DNS.
        \param port Listen port of asynchronous dns server */
    void EnableResolver(port_t port = 16667);
    /** Check resolver status.
        \return true if resolver is enabled */
    bool ResolverEnabled();
    /** Queue a dns request.
        \param host Hostname to be resolved
        \param port Port number will be echoed in Socket::OnResolved callback */
    int Resolve(Socket *,const std::string& host,port_t port);
#ifdef ENABLE_IPV6
    int Resolve6(Socket *,const std::string& host,port_t port);
#endif
    /** Do a reverse dns lookup. */
    int Resolve(Socket *,ipaddr_t a);
#ifdef ENABLE_IPV6
    int Resolve(Socket *,in6_addr& a);
#endif
    /** Get listen port of asynchronous dns server. */
    port_t GetResolverPort();
    /** Resolver thread ready for queries. */
    bool ResolverReady();
    /** Returns true if the socket is waiting for a resolve event. */
    bool Resolving(Socket *);
#endif // ENABLE_RESOLVER

#ifdef ENABLE_TRIGGERS
    /** Fetch unique trigger id. */
    int TriggerID(Socket *src);
    /** Subscribe socket to trigger id. */
    bool Subscribe(int id, Socket *dst);
    /** Unsubscribe socket from trigger id. */
    bool Unsubscribe(int id, Socket *dst);
    /** Execute OnTrigger for subscribed sockets.
        \param id Trigger ID
        \param data Data passed from source to destination
        \param erase Empty trigger id source and destination maps if 'true',
            Leave them in place if 'false' - if a trigger should be called many times */
    void Trigger(int id, Socket::TriggerData& data, bool erase = true);
#endif // ENABLE_TRIGGERS

#ifdef ENABLE_DETACH
    /** Indicates that the handler runs under SocketThread. */
    void SetSlave(bool x = true);
    /** Indicates that the handler runs under SocketThread. */
    bool IsSlave();
#endif

    /** Sanity check of those accursed lists. */
    void CheckSanity();

protected:
    socket_m m_sockets; ///< Active sockets map
    socket_m m_add; ///< Sockets to be added to sockets map
    std::list<Socket *> m_delete; ///< Sockets to be deleted (failed when Add)

protected:
    StdLog *m_stdlog; ///< Registered log class, or NULL
    Mutex& m_mutex; ///< Thread safety mutex
    bool m_b_use_mutex; ///< Mutex correctly initialized

private:
    void CheckList(socket_v&,const std::string&); ///< Used by CheckSanity
    /** Remove socket from socket map, used by Socket class. */
    void Remove(Socket *);
    SOCKET m_maxsock; ///< Highest file descriptor + 1 in active sockets list
    fd_set m_rfds; ///< file descriptor set monitored for read events
    fd_set m_wfds; ///< file descriptor set monitored for write events
    fd_set m_efds; ///< file descriptor set monitored for exceptions
    int m_preverror; ///< debug select() error
    int m_errcnt; ///< debug select() error
    time_t m_tlast; ///< timeout control

    // state lists
    socket_v m_fds; ///< Active file descriptor list
    socket_v m_fds_erase; ///< File descriptors that are to be erased from m_sockets
    socket_v m_fds_callonconnect; ///< checklist CallOnConnect
#ifdef ENABLE_DETACH
    socket_v m_fds_detach; ///< checklist Detach
#endif
    socket_v m_fds_timeout; ///< checklist timeout
    socket_v m_fds_retry; ///< checklist retry client connect
    socket_v m_fds_close; ///< checklist close and delete

#ifdef ENABLE_SOCKS4
    ipaddr_t m_socks4_host; ///< Socks4 server host ip
    port_t m_socks4_port; ///< Socks4 server port number
    std::string m_socks4_userid; ///< Socks4 userid
    bool m_bTryDirect; ///< Try direct connection if socks4 server fails
#endif
#ifdef ENABLE_RESOLVER
    int m_resolv_id; ///< Resolver id counter
    ResolvServer *m_resolver; ///< Resolver thread pointer
    port_t m_resolver_port; ///< Resolver listen port
    std::map<Socket *, bool> m_resolve_q; ///< resolve queue
#endif
#ifdef ENABLE_POOL
    bool m_b_enable_pool; ///< Connection pool enabled if true
#endif
#ifdef ENABLE_TRIGGERS
    int m_next_trigger_id; ///< Unique trigger id counter
    std::map<int, Socket *> m_trigger_src; ///< mapping trigger id to source socket
    std::map<int, std::map<Socket *, bool> > m_trigger_dst; ///< mapping trigger id to destination sockets
#endif
#ifdef ENABLE_DETACH
    bool m_slave; ///< Indicates that this is a ISocketHandler run in SocketThread
#endif
};


#ifdef SOCKETS_NAMESPACE
}
#endif

#endif // _SOCKETS_SocketHandler_H