Socket.cpp

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///////////////////////////////////////////////////////////////////////////////////////////////
/*! \file       ClientSocket.cpp
 *  \brief      Implementation of the Socket class for communicating.
 *
 *              The socket communications classes are based on the tutorial entitled
 *              "Linux Socket Programming In C++" by Rob Tougher on the Linux Gazette
 *              website. ( http://linuxgazette.net/issue74/tougher.html )
 *
 *  \author     Scott A. Kowalchuk
 *  \date       2006/11/29
 */////////////////////////////////////////////////////////////////////////////////////////////
/*
 * \Status
 *
 *
 */
/////////////////////////////////////////////////////////////////////////////////////////////


#include "Socket.h"

/*! \brief Constructor of the socket
 * 
 */
Socket::Socket( ) 
        : m_sock ( -1 )
{
        memset ( &m_addr, 0, sizeof( m_addr ) );
}


/*! \brief Destructor of the socket
 * 
 */
Socket::~Socket( )
{
        if ( is_valid( ) ) 
        {
                ::close ( m_sock );
        }
}

/*! \brief Create socket
 * 
 */
bool Socket::create( )
{
        m_sock = socket ( AF_INET, SOCK_STREAM, 0 );

        if ( ! is_valid() ) 
        {
                return false;
        }

        /* TIME_WAIT */
        int on = 1;
        if ( setsockopt ( m_sock, SOL_SOCKET, SO_REUSEADDR, ( const char* ) &on, sizeof ( on ) ) == -1 )
                return false;

        return true;
}


/*! \brief Bind socket
 * 
 * @param port is the port to communicate with.
 */
bool Socket::bind ( const int port )
{

        if ( ! is_valid() )
        {
                return false;
        }

        m_addr.sin_family = AF_INET;
        m_addr.sin_addr.s_addr = INADDR_ANY;
        m_addr.sin_port = htons ( port );

        int bind_return = ::bind ( m_sock, ( struct sockaddr * ) &m_addr, sizeof ( m_addr ) );

        if ( bind_return == -1 )
        {
                return false;
        }

        return true;
}


/*! \brief Listen to socket
 * 
 */
bool Socket::listen( ) const
{
        if ( ! is_valid() )
        {
                return false;
        }

        int listen_return = ::listen ( m_sock, MAXCONNECTIONS );

        if ( listen_return == -1 )
        {
                return false;
        }

        return true;
}


/*! \brief Accept socket
 * 
 * @param new_socket
 */
bool Socket::accept ( Socket& new_socket ) const
{
        int addr_length = sizeof ( m_addr );
        new_socket.m_sock = ::accept ( m_sock, ( sockaddr * ) &m_addr, ( socklen_t * ) &addr_length );

        if ( new_socket.m_sock <= 0 )
        {
                return false;
        }
        else
        {
                return true;
        }
}


/*! \brief Send string to socket
 * 
 * @param str is the string of data to be sent
 */
bool Socket::send ( const std::string str ) const
{
        int status = ::send ( m_sock, str.c_str(), str.size(), MSG_NOSIGNAL );
        if ( status == -1 )
        {
                return false;
        }
        else
        {
                return true;
        }
}


/*! \brief Receive string from socket
 * 
 * @param str is the string of data to be received
 * @return status
 */
int Socket::recv ( std::string& str ) const
{
        char buf [ MAXRECV + 1 ];

        str = "";

        memset ( buf, 0, MAXRECV + 1 );

        int status = ::recv ( m_sock, buf, MAXRECV, 0 );

        if ( status == -1 )
        {
                std::cout << "status == -1   errno == " << errno << "  in Socket::recv\n";
                return 0;
        }
        else if ( status == 0 )
        {
                return 0;
        }
        else
        {
                str = buf;
                return status;
        }
}


/*! \brief Connect to the host.
 * 
 * @param host is the IP address (xxx.xxx.xxx.xxx) or host name (vt.edu)
 * @param port is the port number for the host
 */
bool Socket::connect ( const std::string host, const int port )
{
        if ( ! is_valid() ) return false;

        m_addr.sin_family = AF_INET;
        
        hostent * hp;
        if( ( hp = gethostbyname( host.c_str() ) ) == NULL )
        {
                std::cerr << "Can't Resolve Host" << std::endl;
                return false;
        }

        m_addr.sin_addr.s_addr=*(u_long *)hp->h_addr;
        
        m_addr.sin_port = htons ( port );

        if ( errno == EAFNOSUPPORT ) return false;

        int status = ::connect ( m_sock, ( sockaddr * ) &m_addr, sizeof ( m_addr ) );

        if ( status == 0 )
                return true;
        else
                return false;
}

/*! \brief Set non blocking.
 * 
 * @param b
 */
void Socket::set_non_blocking( const bool b )
{
        int opts;

        opts = fcntl ( m_sock, F_GETFL );

        if ( opts < 0 )
        {
                return;
        }

        if ( b )
        {
                opts = ( opts | O_NONBLOCK );
        }
        else
        {
                opts = ( opts & ~O_NONBLOCK );
        }

        fcntl ( m_sock, F_SETFL,opts );

}

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