/*Copyright (c) 2000-2002, Jelle Kok, University of AmsterdamAll rights reserved.Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. Neither the name of the University of Amsterdam nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.*//*! \file Connection.C<pre><b>File:</b>          Connection.C<b>Project:</b>       Robocup Soccer Simulation Team: UvA Trilearn<b>Authors:</b>       Jelle Kok<b>Created:</b>       23/11/2000<b>Last Revision:</b> $ID$<b>Contents:</b>      This file contains the class definitions for the               Connection class which sets up a connection with the               soccer server.<hr size=2><h2><b>Changes</b></h2><b>Date</b>             <b>Author</b>          <b>Comment</b>23/11/2000       Jelle Kok       Initial version created</pre>*/#include <errno.h>       // EWOULDBLOCK#include <unistd.h>      // close#include <string>      // strlen#include <sys/types.h>   // socket#include <sys/socket.h>  // socketusing namespace std;#ifdef Solaris#include <sys/socket.h>  // AF_INET SOCK_DGRAM#endif#include "Connection.h"#include "Logger.h"      // LOGextern Logger Log; /*!< This is a reference to the Logger for writing info to.*//******************************************************************************//********************** CONNECTION ********************************************//******************************************************************************//*! Default constructor. Only sets the maximum message size. */Connection::Connection( ){  m_iMaxMsgSize = 2048;}/*! Constructor makes a connection with the server using the connect method.    \param hostname string representation of host machine (string or IP number)    \param port port number for connection of the host machine    \param iMaxSize maximum message size that can be sent or received */Connection::Connection(const char *hostname, int port, int iMaxSize){  m_iMaxMsgSize = iMaxSize;  if(  connect( hostname, port ) )    Log.log( 1, "(Connection:connection) Socket connection made with %s:%d",                                                             hostname, port );  else    Log.log( 1, "(Connection:Connection) Could not create connection with %s:%d"                                                          , hostname, port );}/*! Deconstructor closes the connection with the server */Connection::~Connection(){  disconnect();}/*! This method sets up a connection with the server.    \param hostname string representation of host machine (string or IP number)    \param port port number for connection of the host machine    \return bool indicating whether connection was made */bool Connection::connect(const char *host, int port ){  struct hostent *host_ent;  struct in_addr *addr_ptr;  struct sockaddr_in  cli_addr ;  int    sockfd ;  m_sock.socketfd = -1 ;  if( (host_ent = (struct hostent*)gethostbyname(host)) == NULL)  {    // if not a string, get information from IP adress.#ifdef Solaris    if( inet_addr(host) == ((in_addr_t)-1) )#else    if( inet_addr(host) == INADDR_NONE )#endif    {      cerr << "(Connection::connect) Cannot find host " << host << endl;      return false ;    }  }  else   // get the necessary information from the hostname (string)  {    addr_ptr = (struct in_addr *) *host_ent->h_addr_list;    host = inet_ntoa(*addr_ptr);  }  //  Open UDP socket.  if( (sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0)  {    cerr << "(Connection::connect) Cannot create socket " << host << endl;    return false ;  }  // insert the information of the client  cli_addr.sin_family      = AF_INET ;  cli_addr.sin_addr.s_addr = htonl(INADDR_ANY) ;  cli_addr.sin_port        = htons(0) ;  // bind the client to the server socket  if(bind(sockfd, (struct sockaddr *) &cli_addr, sizeof(cli_addr)) < 0)  {    cerr << "(Connection::connect) Cannot bind local address " << host << endl;    return false ;  }  //  Fill in the structure with the address of the server.  m_sock.socketfd = sockfd ;  m_sock.serv_addr.sin_family       = AF_INET ;  m_sock.serv_addr.sin_addr.s_addr  = inet_addr(host);  m_sock.serv_addr.sin_port         = htons(port) ;  return true;}/*! This method closes the current socket connection.  */void Connection::disconnect( void ){  if (isConnected() )  {    close(m_sock.socketfd) ;    m_sock.socketfd = -1; // This also 'sets' isConnected() to false  }}/*! This method determines whether the socket connection is connected.    \return bool indicating whether socket connection is available */bool Connection::isConnected(void) const{  return(m_sock.socketfd != -1);}/*! This method reads a message from the connection. When there is    no message available, it blocks till it receives a message.    \param msg string in which message is stored    \param maxsize maximum size of the message.    \return -1: error, 0: 0 bytes were read, 1 when read was succesfull */int Connection::receiveMessage( char *msg, int maxsize ){#ifdef Solaris  int       servlen;#else  socklen_t servlen ;#endif  int n;  struct sockaddr_in serv_addr ;  servlen = sizeof(serv_addr) ;  // receive message from server  n = recvfrom(m_sock.socketfd, msg, maxsize, 0,                              (struct sockaddr *)&serv_addr, &servlen);  if(n < 0)                                   // error  {    if( n == -1 && errno == EWOULDBLOCK)    {      msg[0] = '\0' ;      return 0 ;    }    else      return -1;  }  else                                       // succesfull, set new server info  {                                          // next message will go to there    m_sock.serv_addr.sin_port = serv_addr.sin_port ;    msg[n] = '\0' ;    return ( n == 0 ) ? 0 : 1 ;  }}/*! This method sends a message to the server using the current connection.    \param msg string which contains message    \return true on succes, false in case of failure */bool Connection::sendMessage( const char *msg ){  int n;  n = strlen(msg) + 1 ;  if( sendto(m_sock.socketfd, msg, n, 0,      (struct sockaddr *)&m_sock.serv_addr, sizeof(m_sock.serv_addr)) != n )    return false ;  return true ;}/*! This method always loops and waits for input. When input is received from    fpin then this input is send to the server using the current connection.    When message is received from the server, this message is sent to fpout.    \param fpin file pointer from which input is read (i.e. stdin )    \param fpout file pointer to which output should be directed (i.e. stdout)    \return 0 but only when error occured in reading input */int Connection::message_loop( FILE *fpin, FILE *fpout ){  fd_set readfds, readfds_bak;  int in, max_fd, n, ret;  char buf[m_iMaxMsgSize];  in = fileno( fpin );  FD_ZERO( &readfds );  FD_SET( in, &readfds );  readfds_bak = readfds;  max_fd = ((in > m_sock.socketfd) ? in : m_sock.socketfd) = 1;  while( 1 )  {    readfds = readfds_bak;    // wait for message from socket or fpin    if(( ret = select( max_fd, &readfds, NULL, NULL, NULL )) < 0 )    {      perror("select");      break;    }    else if( ret != 0 )    {      if( FD_ISSET(in, &readfds))              // file descriptor fpin was set      {        fgets(buf, m_iMaxMsgSize, fpin);             // get the message        if( sendMessage(buf ) == false )       // and send it          break;      }      if( FD_ISSET(m_sock.socketfd, &readfds ) ) // file descriptor socket was set      {        n = receiveMessage(buf, m_iMaxMsgSize);      // receive the message        if( n == -1 )          break;        else if( n > 0 )                       // and put it to fpout        {          fputs(buf, fpout);          fputc( '\n', fpout);        }        fflush(stdout);      }    }  }  return 0;}/*! This method prints whether the connection is up or not.    \param os output stream to which output should be directed */void Connection::show( ostream os ){  if( ! isConnected() )    os << "Not connected" << endl;  else    os << "Connected" << endl;}/********************** TESTING PURPOSES **************************************//*int main( void ){  char strBuf[m_iMaxMsgSize];  Connection c( "localhost", 6000 );  int i;  c.sendMessage( "(init l (version 6.07))" );  while( 1 )  {    i = c.receiveMessage( strBuf, m_iMaxMsgSize );    printf("%d|%s|\n", i, strBuf );  }  return 0;}*/