tracker.cpp

最新的enhanced ctorrent源码

        "The file is not registered on this tracker, or it may have been removed.");
      CONSOLE.Warning(2,
        "IF YOU SEE THIS MESSAGE FOR A LONG TIME AND DOWNLOAD DOESN'T BEGIN, RECOMMEND YOU STOP NOW!!!");
      CONSOLE.Warning(0, "Tracker reponse data DUMP:");
      if( pdata && dlen )  // write(STDERR_FILENO, pdata, dlen);
        CONSOLE.Warning(0, "%s", pdata);
      CONSOLE.Warning(0, "== DUMP OVER==");
      return -1;
    }else
      return 0;
  }

  if ( !pdata ){
    CONSOLE.Warning(2, "warn, peers list received from tracker is empty.");
    return 0;
  }

  if( !m_f_started ) m_f_started = 1;
  m_connect_refuse_click = 0;
  m_ok_click++;

  return _UpdatePeerList(pdata,dlen);
}

int btTracker::Initial()
{
  char ih_buf[20 * 3 + 1],pi_buf[20 * 3 + 1],tmppath[MAXPATHLEN];
  char *format;

  if(Http_url_analyse(BTCONTENT.GetAnnounce(),m_host,&m_port,m_path) < 0){
    CONSOLE.Warning(1, "error, invalid tracker url format!");
    return -1;
  }

  strcpy(tmppath,m_path);

  if(strchr(m_path, '?'))
    format=REQ_URL_P1A_FMT;
  else format=REQ_URL_P1_FMT;

  char chars[37] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
  for(int i=0; i<8; i++)
    m_key[i] = chars[random()%36];
  m_key[8] = 0;

  if(MAXPATHLEN < snprintf((char*)m_path,MAXPATHLEN,format,
                           tmppath,
                           Http_url_encode(ih_buf,(char*)BTCONTENT.GetInfoHash(),20),
                           Http_url_encode(pi_buf,(char*)BTCONTENT.GetPeerId(),20),
                           cfg_listen_port,
                           m_key)){
    return -1;
  }

  /* get local ip address */
  // 1st: if behind firewall, this only gets local side
  {
  struct sockaddr_in addr;
  socklen_t addrlen = sizeof(struct sockaddr_in);
  if(getsockname(m_sock,(struct sockaddr*)&addr,&addrlen) == 0)
        Self.SetIp(addr);
  }
  // 2nd: better to use addr of our domain
  {
          struct sockaddr_in addr;
          struct hostent *h;
          char hostname[128];
          char *hostdots[2]={0,0}, *hdptr=hostname;

          if (gethostname(hostname, 128) == -1) return -1;
//        CONSOLE.Print("%s", hostname);
          while(*hdptr) if(*hdptr++ == '.') {
            hostdots[0] = hostdots[1];
            hostdots[1] = hdptr;
          }
          if (hostdots[0] == 0) return -1;
//        CONSOLE.Print("%s", hostdots[0]);
          if ((h = gethostbyname(hostdots[0])) == NULL) return -1;
          //CONSOLE.Print("Host domain  : %s", h->h_name);
          //CONSOLE.Print("IP Address : %s", inet_ntoa(*((struct in_addr *)h->h_addr)));
          memcpy(&addr.sin_addr,h->h_addr,sizeof(struct in_addr));
          Self.SetIp(addr);
  }
  return 0;
}

int btTracker::Connect()
{
  ssize_t r;
  time(&m_last_timestamp);

  if(_s2sin(m_host,m_port,&m_sin) < 0) {
    CONSOLE.Warning(2, "warn, get tracker's ip address failed.");
    return -1;
  }

  m_sock = socket(AF_INET,SOCK_STREAM,0);
  if(INVALID_SOCKET == m_sock) return -1;

  // we only need to bind if we have specified an ip
  // we need it to bind here before the connect!!!!
  if ( cfg_listen_ip != 0 ) {
    struct sockaddr_in addr;
    // clear the struct as requested in the manpages
    memset(&addr,0, sizeof(sockaddr_in));
    // set the type
    addr.sin_family = AF_INET;
    // we want the system to choose port
    addr.sin_port = 0;
    // set the defined ip from the commandline
    addr.sin_addr.s_addr = cfg_listen_ip;
    // bind it or return...
    if(bind(m_sock,(struct sockaddr*)&addr,sizeof(struct sockaddr_in)) != 0){
      CONSOLE.Warning(1, "warn, can't set up tracker connection:  %s",
        strerror(errno));
      return -1;
    }
  }

  if(setfd_nonblock(m_sock) < 0) {CLOSE_SOCKET(m_sock); return -1; }

  r = connect_nonb(m_sock,(struct sockaddr*)&m_sin);

  if( r == -1 ){ CLOSE_SOCKET(m_sock); return -1;}
  else if( r == -2 ) m_status = T_CONNECTING;
  else{
    if( 0 == SendRequest()) m_status = T_READY;
    else{ CLOSE_SOCKET(m_sock); return -1;}
  }
  return 0;
}

int btTracker::SendRequest()
{
  char *event,*str_event[] = {"started","stopped","completed" };
  char REQ_BUFFER[2*MAXPATHLEN];
  struct sockaddr_in addr;

  if( m_f_stoped )
    event = str_event[1];	/* stopped */
  else if( !m_f_started ){
    if( BTCONTENT.pBF->IsFull() ) m_f_completed = 1;
    event = str_event[0];	/* started */
  }else if( BTCONTENT.pBF->IsFull() && !m_f_completed ){
    if( Self.TotalDL() > 0 ) event = str_event[2];  /* download complete */
    else event = (char*) 0;  /* interval */
    m_f_completed = 1;		/* only send download complete once */
  }else
    event = (char*) 0;  /* interval */

  if(event){
    if(MAXPATHLEN < snprintf(REQ_BUFFER,MAXPATHLEN,REQ_URL_P2_FMT,
                             m_path,
                             (unsigned long long)(Self.TotalUL()),
                             (unsigned long long)(Self.TotalDL()),
                             (unsigned long long)(BTCONTENT.GetLeftBytes()),
                             event,
                             (int)cfg_max_peers,
                             m_key)){
      return -1;
    }
  }else{
    if(MAXPATHLEN < snprintf(REQ_BUFFER,MAXPATHLEN,REQ_URL_P3_FMT,
                             m_path,
                             (unsigned long long)(Self.TotalUL()),
                             (unsigned long long)(Self.TotalDL()),
                             (unsigned long long)(BTCONTENT.GetLeftBytes()),
                             (int)cfg_max_peers,
                             m_key)){
      return -1;
    }
  }
  if( *m_trackerid &&
      MAXPATHLEN - strlen(m_path) > 11 + strlen(m_trackerid) )
    strcat(strcat(m_path, "&trackerid="), m_trackerid);

  // if we have a tracker hostname (not just an IP), send a Host: header
  if(_IPsin(m_host, m_port, &addr) < 0){
    char REQ_HOST[MAXHOSTNAMELEN];
    if(MAXHOSTNAMELEN < snprintf(REQ_HOST,MAXHOSTNAMELEN,"\r\nHost: %s",m_host))
      return -1;
    strcat(REQ_BUFFER, REQ_HOST);
  }

  strcat(REQ_BUFFER, "\r\nUser-Agent: ");
  strcat(REQ_BUFFER, cfg_user_agent);

  strcat(REQ_BUFFER,"\r\n\r\n");
  // hc
  //CONSOLE.Warning(0, "SendRequest: %s", REQ_BUFFER);

  if( 0 !=
      m_reponse_buffer.PutFlush(m_sock,REQ_BUFFER,strlen((char*)REQ_BUFFER)) ){
    CONSOLE.Warning(2,
      "warn, send request to tracker failed:  %s", strerror(errno));
    if( event == str_event[2] )
      m_f_completed = 0;  // failed sending completion event
    return -1;
  }

  return 0;
}

int btTracker::IntervalCheck(fd_set *rfdp, fd_set *wfdp)
{
  /* tracker communication */
  if( T_FREE == m_status ){
    if( now - m_last_timestamp >= m_interval ||
        // Connect to tracker early if we run low on peers.
        (WORLD.GetPeersCount() < cfg_min_peers &&
          m_prevpeers >= cfg_min_peers && now - m_last_timestamp >= 15) ){
      m_prevpeers = WORLD.GetPeersCount();

      if(Connect() < 0){ Reset(15); return -1; }

      FD_SET(m_sock, rfdp);
      if( m_status == T_CONNECTING ) FD_SET(m_sock, wfdp);
    }else if( now < m_last_timestamp ) m_last_timestamp = now;
  }else{
    if( m_status == T_CONNECTING ){
      FD_SET(m_sock, rfdp);
      FD_SET(m_sock, wfdp);
    }else if (INVALID_SOCKET != m_sock){
      FD_SET(m_sock, rfdp);
    }
  }
  return m_sock;
}

int btTracker::SocketReady(fd_set *rfdp, fd_set *wfdp, int *nfds,
  fd_set *rfdnextp, fd_set *wfdnextp)
{
  if( T_FREE == m_status ) return 0;

  if( T_CONNECTING == m_status && FD_ISSET(m_sock,wfdp) ){
    int error = 0;
    socklen_t n = sizeof(error);
    (*nfds)--;
    FD_CLR(m_sock, wfdnextp); 
    if( FD_ISSET(m_sock, rfdp) ){
      (*nfds)--;
      FD_CLR(m_sock, rfdnextp);
    }
    if(getsockopt(m_sock, SOL_SOCKET,SO_ERROR,&error,&n) < 0 ||
       error != 0 ){
      if( ECONNREFUSED != error ){
        CONSOLE.Warning(2,
          "warn, connect to tracker failed:  %s", strerror(error));
      }else
        m_connect_refuse_click++;
      Reset(15);
      return -1;
    }else{
      if( SendRequest() == 0 ) m_status = T_READY; 
      else { Reset(15); return -1; }
    }
  }else if( T_CONNECTING == m_status && FD_ISSET(m_sock,rfdp) ){
    int error = 0;
    socklen_t n = sizeof(error);
    (*nfds)--;
    FD_CLR(m_sock, rfdnextp);
    getsockopt(m_sock, SOL_SOCKET,SO_ERROR,&error,&n);
    CONSOLE.Warning(2, "warn, connect to tracker failed:  %s", strerror(error));
    Reset(15);
    return -1;
  }else if(INVALID_SOCKET != m_sock && FD_ISSET(m_sock, rfdp) ){
    (*nfds)--;
    FD_CLR(m_sock,rfdnextp);
    CheckReponse();
  }
  return 0;
}

void btTracker::Resume()
{
  m_f_pause = m_f_stoped = 0;

  if( T_FINISHED == m_status ){
    m_status = T_FREE;
    m_f_started = 0;
    m_interval = 15;
  }
}